Day: 02/24/2024

Eating Plant Protein Linked to Reduced Risk of Chronic Diseases and Extended Lifespan

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Eating protein from plant sources, supplemented with a small amounts of animal protein during midlife, contributes to better overall physical health.

Study: Eating Plant Protein Linked to Reduced Risk of Chronic Diseases and Extended Lifespan

Protein is a vital nutrient for the human body. Among various protein sources, plant proteins contain lower levels of fat and cholesterol while also containing more dietary fiber. Recent research has shown that increasing the intake of plant proteins not only reduces the risk of chronic diseases but also contributes to an extended lifespan.

11 Chronic Diseases Reduced

A study published in The American Journal of Clinical Nutrition in February indicated that women who ate more plant protein in midlife had a lower likelihood of developing 11 chronic diseases as they aged. Additionally, their mental health, cognitive function, and physical well-being appeared to be better.

The study analyzed data from 48,762 participants in the Nurses’ Health Study with a mean initial age of about 48 years, who were followed for more than 30 years. The researchers examined their intake of total protein, animal protein, dairy protein, and plant protein to assess the relationship between protein intake levels, protein types, and healthy aging.

The study defined healthy aging as the absence of 11 major chronic diseases, good mental health, and unimpaired memory and physical functions. The diseases were reported as:

  1. Cancer (excluding nonmelanoma skin cancer)
  2. Type 2 diabetes
  3. Myocardial infarction (heart attack)
  4. Stroke
  5. Coronary artery bypass graft surgery
  6. Congestive heart failure
  7. Chronic obstructive pulmonary disease
  8. Kidney failure
  9. Multiple sclerosis
  10. Amyotrophic lateral sclerosis
  11. Parkinson’s disease

The participants’ intake of animal protein sources included beef, chicken, fish, and seafood, as well as dairy protein sourced from milk, cheese, pizza, yogurt, and ice cream. Plant protein primarily came from bread, fruits, vegetables, cereals, legumes, beans, peanut butter, mashed potatoes, and pasta.

The results highlighted that for every 3 percent increment in the consumption of plant protein in the diet, the likelihood of experiencing healthy aging in the future rose by 38 percent. Additionally, dairy protein intake demonstrated a 14 percent increase, while animal protein showed a 7 percent increase, and total protein exhibited a 5 percent rise in the likelihood of healthy aging.

The researchers also found that substituting 3 percent of total energy intake with plant protein in place of equivalent calories from saturated fatty acids, polyunsaturated fatty acids, monounsaturated fatty acids, animal protein, or dairy protein significantly increased the odds of healthy aging by 22 to 58 percent.

Andres Ardisson Korat, the lead author of the study, stated in a press release that consuming more protein from plant sources, supplemented with a small amount of animal protein during midlife, contributes to better physical health and overall well-being in older age

Specifically, the researchers found that participants who ate more protein from fruits, vegetables, legumes, bread, and pasta had a notably lower likelihood of developing heart disease, cancer, and diabetes compared to those who ate these foods less. Additionally, they experienced less decline in cognitive and mental health.

This was particularly evident in the context of heart disease, where a higher intake of plant protein was associated with lower levels of LDL cholesterol, blood pressure, and insulin sensitivity. Conversely, a higher intake of animal protein was linked to elevated levels of these factors, along with an increase in insulin-like growth factor, which has been identified in various types of cancer.

Ardisson Korat remarked, “Those who consumed greater amounts of animal protein tended to have more chronic disease and didn’t manage to obtain the improved physical function that we normally associate with eating protein.”

Reducing Mortality With Increased Plant Protein Intake

A large population-based study published in JAMA Internal Medicine in 2020 suggested that partially replacing animal protein with plant protein was associated with a reduced overall mortality. The study included 416,104 participants with a median age of around 62 years and a follow-up period of 16 years.

The findings indicated that replacing 3 percent of animal protein with plant protein in total energy intake reduced overall mortality by 10 percent in both men and women. Notably, substituting plant protein for egg protein was associated with a 24 percent decrease in overall mortality risk for men and a 21 percent decrease for women. Replacing plant protein for red meat protein resulted in a 13 percent decrease in overall mortality in men and a 15 percent decrease in women. However, substituting plant protein for 3 percent of total energy intake from white meat protein did not show a significant association with mortality risk.

Dr. “JJ” Shaw, a certified sports nutrition expert by the International Society of Sports Nutrition, expressed in his blog post that plant-based proteins contain unsaturated fatty acids, antioxidants, phytochemicals, and vitamins, which can reduce inflammation. On the other hand, animal-based proteins, especially those in red meat, contain higher levels of heme, iron, carnitine, and nitrites, contributing to increased inflammation in the body.

Dr. Shaw mentioned that he always keeps baked black beans and pumpkin seeds at home as go-to snacks. These two snacks are considered among the least fattening, not only supporting overall health but also providing a rich source of protein. People with a balanced diet typically do not require additional vitamin supplements.

He pointed out that edamame, black beans, and (organic) yellow soybeans boast high protein and low fat content. While containing some starch, legumes feature enzymes that inhibit starch-degrading enzymes, leading to a notably low glycemic index. As such, they serve as excellent sources for protein supplementation.

Remin Kao, a nutritionist from Taiwan, notes that although pumpkin seeds and peanuts are rich in plant proteins, they also belong to the fats category. When incorporating them into your diet, it is important to be mindful of portion sizes. It is advisable not to exceed a small handful (approximately 30 grams or about 1 ounce) per day.

Ms. Kao stated that the recommended daily protein intake for a healthy adult should be approximately equal to body weight (in pounds) multiplied by 0.36 grams. A palm-sized portion of plant-based protein typically contains between 21 to 35 grams of protein.

She noted that a deficiency in quality protein could potentially result in reduced muscle mass, slowed metabolism, persistent fatigue, and a decline in energy levels.

Processed Foods Linked to ‘Forever Chemicals’ in Human Blood: Study

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Consuming foods rich in fiber such as fruits, vegetables, and grains helps in reducing chemical concentrations, the research suggested.

High consumption of processed and packaged foods results in increased levels of certain chemicals in the body known to trigger health complications, according to a recent study.

The peer-reviewed study, published in the journal Environment International on Feb. 4, investigated how dietary habits influenced blood PFAS concentrations among young adults. Perfluoroalkyl and polyfluoroalkyl substances (PFAS), also known as “forever chemicals,” have been linked to multiple adverse health issues including cancers and negative effects on immune function and reproduction.

They are used in furniture, fabric, and several other household items. Recent tests show that the chemicals are present in drinking water, food packaging, and livestock.

Researchers analyzed food consumption data from 727 young adults and determined that higher intake of items such as processed meats, tea, and food prepared outside the home was associated with increased PFAS levels in the body over time.

“We’re starting to see that even foods that are metabolically quite healthy can be contaminated with PFAS,” said Hailey Hampson, a doctoral student in the Keck School of Medicine’s Division of Environmental Health and the study’s lead author, in a news release. “These findings highlight the need to look at what constitutes ‘healthy’ food in a different way.”

The study looked at 123 young adults from the Southern California Children’s Health Study (CHS) who were primarily Hispanic, as well as 604 young adults from the National Health and Nutrition Examination Study (NHANES), a nationally representative sample

Each participant answered several questions about their diet, including how frequently they consumed various foods and beverages. They revealed how often they ate food prepared at home, at fast food restaurants, and at non-fast food restaurants.

Participants also gave blood samples that were tested for PFAS levels. The CHS group was tested twice while the NHANES group was tested once.

Processed Meats

Researchers found that “higher intakes of pork, hot dogs, beef, and other processed meats were associated with higher PFAS concentrations” in both groups. They suggested that PFAS “may accumulate in meat products through several exposure sources.”

“Processed meats such as sausages, bacon, and hot dogs may accumulate PFAS through contact during processing or cooking. Other forms of meat, such as unprocessed pork and beef, may come from animals that were raised in PFAS-contaminated areas or were packaged in grease-resistance packaging that contains PFAS.

Higher intake of tea was observed to be linked to high PFAS in CHS and NHANES groups. The study speculated that PFAS presence via tea could be coming through tea bags made of paper. It pointed out that “paper products are a major contamination source for PFAS.”

In the NHANES group, a higher intake of cakes and cupcakes was found linked to elevated PFAS concentration in blood. As dessert wrappers have been shown to be highly fluorinated, it is possible that high PFAS blood levels in this case came from packaging materials.

Researchers cited an earlier analysis which showed that dietary fiber intake could reduce PFAS blood levels. As such, consuming foods rich in fiber such as fruits, grains, and vegetables helps to reduce PFAS concentrations.

The study received funding from the National Institute of Environmental Health Sciences (NIEHS), the U.S. Environmental Protection Agency (EPA), the Hastings Foundation, and the National Institutes of Health (NIH). The authors declared no competing interests.

Packaging Contamination

Since PFAS-contaminated packaging materials are used in the food industry, the study looked at exposure to chemicals from fast food joints and restaurants.

Researchers analyzed popularly ordered food items such as burgers, fries, hot dogs, burritos, tacos, fajitas, and pizzas. When these items were ordered from fast food joints or restaurants, PFAS levels were observed to be higher. In contrast, the same items prepared at home did not exhibit elevated PFAS concentrations.

“These results suggest that fast food may provide higher PFAS exposures, which could be from grease-resistant food packaging containing PFAS.”

The findings suggest that public monitoring of food and beverage products could aid in identifying and eliminating the source of contamination.

Some states have taken steps in this regard. Last year, the attorney general of California issued an advisory letter asking businesses manufacturing paper straws and food packaging material to reveal the PFAS levels of their products.

“That’s a really good step in the right direction, and our findings highlight the need for more of those types of regulations across the country,” said Jesse A. Goodrich, an assistant professor of population and public health sciences at the Keck School of Medicine and the study’s senior author.

“To our knowledge, this is the first study to examine how dietary factors are associated with changes in PFAS over time. Looking at multiple time points gives us an idea of how changing people’s diets might actually impact PFAS levels.”

PFAS Presence

A study by the U.S. Geological Survey (USGS) last year tested tap water samples from 716 locations across the country, checking for the presence of 32 types of PFAS. The agency determined that at least one PFAS on average was detected in about 45 percent of the tap water samples.

“USGS scientists tested water collected directly from people’s kitchen sinks across the nation, providing the most comprehensive study to date on PFAS in tap water from both private wells and public supplies,” the agency’s research hydrologist Kelly Smalling, the study’s lead author, said in a statement on July 5.

PFAS are called “forever chemicals” as they do not easily break down in the human body or in the environment.

Even plant-based straws, touted widely as eco-friendly, have been found to contain forever chemicals. In an August 2023 study, researchers examined PFAS concentrations in 39 brands of straws sold in the Belgian market made from five materials: paper, bamboo, glass, stainless steel, and plastic.

“PFAS were found to be present in almost all types of straws, but primarily in those made from plant-based materials” such as paper and bamboo, the study said.

Stevia Has Potential Side Effects on Gut Microbiome and Brain, but Experts Explain Bottom Line

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The sugar substitute is known for its potential to lower blood pressure and blood sugar, but some research suggests it may disrupt more than the gut microbiome

Stevia, known for its zero calories and potential benefits, such as lowering blood pressure and blood sugar, is often considered an excellent substitute for sugar. However, is this sweetener—used by Paraguayans for over a thousand years and by the Japanese for several decades—truly free from side effects?

Stevia Is Excreted, but Liver Problems May Pose Issue

Generally, stevia is thought to be metabolized and excreted without accumulating in the body.

Stevia’s sweetness comes from steviol glycosides. Steviol glycosides are a group of substances, among which stevioside and rebaudioside A are the two most common in commercial products.

Our stomachs and upper small intestines cannot break down or absorb steviol glycosides. Therefore, ingested steviol glycosides enter the lower gastrointestinal tract intact. In the colon, gut bacteria break down steviol glycosides into steviol, a process completed within 24 hours. Subsequently, most of the steviol is rapidly absorbed into the bloodstream through the intestinal wall, while any unabsorbed steviol is excreted in feces. The steviol entering the bloodstream is further metabolized into steviol glucuronide in the liver and ultimately excreted in the urine. This is why human experiments have shown no detectable levels of steviol in the blood after consuming steviol glycosides, while steviol glucuronide is detected in urine, and steviol is found in the feces.

“Factors like diet, medication use, or individual differences could potentially impact the metabolism of stevia and its metabolites,” said Lisa Young, an adjunct professor of nutrition in the Department of Nutrition and Food Studies at New York University and a registered dietitian nutritionist, in an email interview with The Epoch Times. She noted that while rare, some individuals may experience adverse reactions or intolerance to steviol, which “could cause gastrointestinal symptoms, allergic reactions, or other health concerns.”

Additionally, she emphasized the crucial role of the liver in the metabolism of stevia, indicating that liver diseases or impaired liver function may impact this process. “Individuals with liver diseases or those taking medications that affect liver function may need to exercise caution regarding the consumption of stevia.”

Potential Impact of Stevia on Gut Microbiome

Some in vitro and animal experiments have found that stevia or steviol may potentially impact the gut microbiome.

An animal study published in Nutrients in 2019 revealed that, compared to those only drinking water, rebaudioside A consumption altered the gut microbiome composition in mice. However, Ms. Young noted that while the hindgut microbiome of mice and humans share some similarities, many bacteria present in the mouse gut are absent in humans. Therefore, there are certain limitations to animal studies

A study conducted by Israeli scientists in 2020 revealed that stevia and steviol do not possess bactericidal properties. However, they may potentially interrupt communication among Gram-negative bacteria in the gut, leading to gut microbial imbalance. Additionally, steviol may also exhibit inhibitory effects on the competition among gut bacteria

Lactobacillus reuteri is often incorporated into food as a probiotic. In an earlier study, stevioside and rebaudioside A were found to inhibit the growth of six strains of Lactobacillus reuteri, with the inhibitory effects varying depending on the specific strain.

An in vitro experiment published in the journal Genes in 2019 suggested that in a simulated human intestinal environment, steviol decreased the population of Bifidobacteria (healthy bacteria), hindered the degradation of bacterial food, and concurrently led to an increase in colonic pH.

Another in vitro experiment, published in the Journal of Agricultural and Food Chemistry in 2019, demonstrated that sweetener products containing steviol glycosides and erythritol altered the structure and diversity of the human gut microbiome to some extent. However, the study concluded that, overall, there was no negative impact on the gut microbial community due to the consumption of stevia.

A review published in Microbiology in 2022 indicated that current knowledge about stevia’s impact on the gut microbiome has primarily come from in vitro and animal studies. Due to a lack of randomized clinical trials conducted in human populations, there is no definitive evidence to elucidate how stevia influences the gut microbiome, and further research is needed.

Ms. Young noted that the impact stevia has on the gut microbiome remains an active area of research, and conclusions may vary. However, she emphasized that “most studies face limitations in terms of biological relevance because it is challenging to directly apply tested concentrations to human exposure levels.”

Gastrointestinal Discomfort Caused by Stevia-Based Products

The adverse effects of stevia-based products often do not stem from steviol glycosides.

As steviol glycosides are several hundred times sweeter than sucrose, most stevia-based products on the market are not 100 percent pure steviol glycosides. Instead, they often consist of a blend of steviol glycosides and some sugar alcohols. For example, you might find a combination of 1 percent steviol glycosides and 99 percent erythritol. These products are commonly found in supermarkets, usually as white crystalline powders, their appearance resembling that of granulated or powdered sugar.

Ms. Young stated that erythritol, present in stevia-based products, is recognized by the U.S. Food and Drug Administration (FDA) as generally recognized as safe (GRAS). However, excessive consumption can result in side effects such as bloating, cramps, flatulence, or diarrhea. Additionally, the inclusion of other substances like sugar alcohol in stevia products may also cause adverse effects, especially for individuals sensitive to these additives.

There are eight types of sugar alcohols approved by relevant regulatory authorities for use as sweeteners in food, including erythritol, hydrogenated starch hydrolysates, lactitol, isomalt, mannitol, maltitol, sorbitol, and xylitol. Some individuals may experience various gastrointestinal discomforts after consuming these substances.

Specifically, sugar alcohol substances may increase gas production after fermentation by bacteria in the gut, contributing to bloating in the gastrointestinal tract. Additionally, these substances can lead to the retention of water in the small intestine, causing abdominal discomfort. Sugar alcohols also impose a greater osmotic load on the gut, leading to increased water concentration in the colon and resulting in loose stools. Moreover, the fermentation of sugar alcohols in the gut may impact the intestinal environment by altering the gut microbiome and its metabolism, influencing the intestinal immune barrier, and potentially increasing the risk of a so-called “leaky gut.”

However, it is important to note that there is a significant variation in symptoms among those who consume sugar-alcohol substances. Factors such as the type of sugar alcohol, the amount ingested, the consumption of food alongside the substance, and the intestinal ability to reabsorb water can all lead to different outcomes. Moreover, people with lower gastrointestinal tolerance or those with intestinal diseases tend to experience more symptoms than healthy people.

The substances present in stevia-based products may also impact cardiovascular health.

A review published in Nature Medicine in 2023 highlighted a link between erythritol consumption and an increased risk of adverse cardiovascular events (including death or nonfatal heart attacks or strokes) and the formation of thrombosis. The researchers stated that further research on the long-term safety of erythritol is warranted. However, it is important to note that some controversy surrounds this study.

Potential Impact of Stevia on the Brain and Nervous System

Scientists have also assessed the potential impact of stevia and its metabolites on the brain and nervous system. However, due to medical ethical considerations, these studies are primarily conducted through animal experiments.

The previously mentioned 2019 animal study suggested that the consumption of stevia may impact the dopamine reward system in the brain.

In 2020, two clinical doctors jointly published a case report, suggesting for the first time a potential association between the symptoms of restless legs syndrome (RLS) and the consumption of stevia. A patient developed symptoms of RLS while using stevia, and these symptoms resolved after discontinuation. Several months later, upon a trial reintroduction of stevia, the RLS symptoms reappeared within two days. The doctors proposed that stevia might selectively reduce dopamine levels in specific regions of the brain, or the intake of stevia could affect iron absorption. Both factors are considered significant contributors to RLS.

In addition to potentially affecting the dopamine system, animal experiments have shown that stevia may also influence memory.

Researchers at the University of Southern California published a study in 2022 where they provided juvenile rats with either artificial sweeteners or water with added stevia for a month and then tested their memory. The results revealed that both artificial sweeteners and stevia impaired the rats’ memory compared to those only drinking water. These rats were less likely to remember objects or navigate through mazes successfully. A study conducted by Filipino researchers in 2015 revealed that mice consuming stevia or two other artificial sweeteners (aspartame and sucralose) showed no significant difference in their learning ability in a water maze compared to mice drinking only water. However, mice consuming stevia exhibited higher levels of cell death in the hippocampus. Another study also conducted in the Philippines in 2014 found that mice with a higher intake of stevia, compared to those only drinking water, exhibited a longer duration of reaction when subjected to heat, suggesting that stevia might inhibit the sensitivity of the mice’s nervous system.

Stevia May Disrupt Endocrine Function and Affect Immunity

In the body, steviol glycosides are first metabolized into steviol, which possesses a steroid-like structure. Therefore, researchers suspect that stevia may act as an endocrine disruptor.

For instance, a cell experiment demonstrated that a certain concentration of steviol could disrupt the endocrine function of human sperm cells and also impact cell viability.

Another study found that stevia consumption led to changes in the number of immune cells in the lymph nodes of mice. Compared to mice drinking only water, those consuming stevia showed an increase in the count of two types of immune cells and a decrease in another type. Additionally, there were varying degrees of changes in some hormones within the mice’s bodies.

In 2020, Brazilian researchers published an in vitro study in Immunopharmacology and Immunotoxicology, revealing that exposure to steviol led to a decrease in human lymphocyte quantity, accompanied by gradual DNA damage and structural changes. Therefore, the study proposed that, under certain concentrations and conditions, steviol exhibits cytotoxic, genotoxic, and mutagenic effects. An earlier study also suggested that, although steviol glycosides seem not to exhibit cytotoxicity, steviol itself possesses mutagenic properties.

Safety of Stevia in Human Studies

However, the experiments mentioned above, which indicate the effects of stevia or its metabolites, were not conducted on humans. In other words, the experimental conditions and subjects differ from those of the human body.

Per Bendix Jeppesen, who is currently studying stevia extract as an anti-diabetic drug and as a healthy sweetener and is an associate professor in the department of endocrinology and diabetes at Aarhus University in Denmark, told The Epoch Times that stevia is safe, stating, “It is the most researched sweetener in the world.” He elaborated: “The European Food Safety Authority (EFSA) are using 10 years to go through all materials. All kinds of studies and publications have been really looked into and they gave this permission (to use stevia).”

Mr. Jeppesen also pointed out, “Cell studies will never be able to replace in vivo studies as animal or human intervention studies.” This is because, in in vivo studies, the human body functions as a whole organism, with different organs working together, whereas in cell studies, it typically involves cells from a specific organ and cannot fully reflect the overall complexity of the organ.

Jan Geuns, a professor in the Department of Biology at Katholieke Universiteit Leuven in Belgium, who has researched stevia for many years, expressed in an email to The Epoch Times that extensive experiments have been conducted on animals as well as healthy subjects. Throughout the process, “we hoped to find other metabolites than steviol or steviol glucuronide. However, no other metabolites could be found.” He also pointed out that steviol glycosides and their metabolites do not accumulate in the human body.

Mr. Geuns also mentioned that “steviol glycosides are not easily absorbed in cells and, therefore, cell studies have nothing to do with the way steviol glycosides behave in man.” Additionally, he explained that once excreted from the body, steviol glucuronide continues to be further degraded by microorganisms, including those in the soil, and does not accumulate in the environment. “This cannot be said about compounds like sucralose, which has recently been proven to be carcinogenic and which is accumulating in surface waters and occurs in tap water.

“I think that sufficient studies have been done on the safety of steviol glycosides (and stevia),” he concluded.

A 2021 review recognized the safety of stevia, citing as primary evidence its historical use in the Paraguayan population for over 1,500 years and decades-long consumption by the Japanese without any reported side effects.

A study published in Nutrition Today in 2015 proposed that there were over 200 studies at that time confirming the safety of stevia. Additionally, a review published in 2023 in the journal Molecules also asserted that most existing human experiments suggest the safety of stevia consumption for the general population—“Although neither the applicability of stevioside in children, pregnancy, nor lactation has been evaluated, preclinical and clinical evidence of its safety allows it to be recommended, respecting the [acceptable daily intake

Do You Have a Hormone Imbalance?

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Your Hormones, Your Health

Your Hormones, Your Health

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Feeling bloated, irritable, or just not your best? Shifts in your hormones could be to blame. Hormones are chemical “messengers” that impact the way your cells and organs function. It’s normal for your levels of them to shift at different times of your life, such as before and during your period or a pregnancy, or during menopause. But some medications and health issues can cause your levels to go up or down, too.

Appetite and Weight Gain

Appetite and Weight Gain

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You may gain weight during hormonal shifts, such as menopause. But hormone changes don’t directly affect your weight. Instead, it likely happens because of other factors, like aging or lifestyle. For example, when you’re feeling blue or irritated, as you can be when your estrogen levels drop, you may want to eat more. It can also impact your body’s levels of leptin, a hunger-revving hormone.

Sudden Weight Loss

Sudden Weight Loss

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Your thyroid gland helps control how fast your body turns food into fuel, as well as your heart rate and temperature. When it makes too many hormones — or doesn’t make enough — your weight can drop. If you’ve lost 10 pounds or more but haven’t been working out more or eating differently, let your doctor know.

Irregular Periods

Irregular Periods

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Most women’s periods come every 21 to 35 days. If yours doesn’t arrive around the same time every month, or you skip some months, it might mean that certain hormones (estrogen and progesterone) are too high or too low. The reason for that can be perimenopause — the time before menopause — if you’re in your 40s or early 50s. But irregular periods can also be a symptom of health problems like polycystic ovary syndrome (PCOS). Talk to your doctor.

Sleep Problems

Sleep Problems

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If you aren’t getting enough shut-eye, or if the sleep you get isn’t good, your hormones could be at play. Progesterone, a hormone released by your ovaries, helps you catch ZZZs. When levels fall during your menstrual cycle, for example, you may have a hard time falling asleep. Low levels of estrogen can trigger hot flashes and night sweats, both of which can make it tough to get the rest you need.

Chronic Acne

Chronic Acne

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A breakout before or during your period is normal. But acne that won’t clear up can be a symptom of hormone problems. An excess of androgens (“male” hormones that both men and women have) can cause your oil glands to overwork. Androgens also affect the skin cells in and around your hair follicles. Both of those things can clog your pores and cause acne.

Dry Skin

Dry Skin

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A shift in hormones can leave your skin parched. This can happen during menopause, when your skin naturally starts to thin and can’t hold onto as much moisture as it used to. A thyroid issue could also be to blame. A dermatologist can help improve the look of your skin, but if you have other symptoms, you may also want to see your primary care provider.

Memory Fog

Memory Fog

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Experts aren’t sure exactly how hormones impact your brain. What they do know is that changes in estrogen and progesterone can make your head feel “foggy” and make it harder for you to remember things. Some experts think estrogen might impact brain chemicals called neurotransmitters. Attention and memory problems are especially common during perimenopause and menopause. But they can also be a symptom of other hormone-related conditions, like thyroid disease. So, let your doctor know if you’re having trouble thinking clearly.

Belly Problems

Belly Problems

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Your gut is lined with tiny cells called receptors that respond to estrogen and progesterone. When these hormones are higher or lower than usual, you might notice changes in how you’re digesting food. That’s why diarrhea, stomach pain, bloating, and nausea can crop up or get worse before and during your period. If you’re having digestive woes as well as issues like acne and fatigue, your hormone levels might be off.

Ongoing Fatigue

Ongoing Fatigue

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Are you tired all the time? Fatigue is one of the most common symptoms of a hormone imbalance. Excess progesterone can make you sleepy. And if your thyroid — the butterfly-shaped gland in your neck — makes too little thyroid hormone, it can sap your energy. A simple blood test called a thyroid panel can tell you if your levels are too low. If they are, you can get treated for that.

Night Sweats

Night Sweats

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If you wake up drenched, low estrogen could be the cause. Many women have night sweats around the start of menopause. Other hormone issues can cause them, too.

Mood Swings and Depression

Mood Swings and Depression

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Researchers think drops in hormones or fast changes in their levels can cause moodiness and the blues. Estrogen affects key brain chemicals like serotonin, dopamine, and norepinephrine. But other hormones, that travel the same paths as neurotransmitters, also play a part in how you feel.

Hair Loss and Thinning Hair

Hair Loss and Thinning Hair

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When hormones like estrogen drop, others in your body, like testosterone, start to have a bigger impact. The result is thinning hair or hair loss. You could notice this during pregnancy, menopause, or after you start birth control pills.

Headaches

Headaches

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Lots of things can trigger these. But for some women, drops in estrogen bring them on. That’s why it’s common for headaches to strike right before or during your period, when estrogen is on the decline. Regular headaches or ones that often surface around the same time each month can be a clue that your levels of this hormone might be shifting.

Vaginal Dryness

Vaginal Dryness

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It’s normal to have this occasionally. But if you often notice that you’re dry or irritated down there, low estrogen levels may be the reason. The hormone helps vaginal tissue stay moist and comfortable. If your estrogen levels drop because of an imbalance, it can reduce vaginal fluids and cause tightness.

Loss of Libido

Loss of Libido

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Most people think of testosterone as a male hormone, but women’s bodies make it, too. If your testosterone levels are lower than usual, you might have less of an interest in sex than you usually do.

Breast Changes

Breast Changes

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A drop in estrogen can make your breast tissue less dense. And an increase in the hormone can thicken this tissue, even causing new lumps or cysts. Talk to your doctor if you notice breast changes, even if you don’t have any other symptoms that concern you.

Thirst

Thirst

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Both estrogen and progesterone can affect the amount of water in your body. When their levels change — like they do before or at the start of your period — you can find yourself more thirsty than usual. Thirst can also be a sign that your body isn’t making enough anti-diuretic hormone (ADH), which helps you retain a healthy amount of water. This can cause a condition called diabetes insipidus.

Study Backs Recommended Antibiotic Approach for Aspiration Pneumonia

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Evidence of more side effects, lack of survival benefit with extended anaerobic coverage.Share on Facebook. Opens in a new tab or window

An x-ray image of a patient's lungs with aspiration pneumonia

Antibiotic therapy with extended anaerobic coverage (EAC) was not associated with a survival benefit in patients with community-acquired aspiration pneumonia, according to results from a retrospective cohort study that support current guidelines.

Across 18 hospitals in Canada, in-hospital mortality rates were 30.3% for patients treated with antibiotic therapy with limited anaerobic coverage (LAC) and 32.1% for those treated with EAC, rates that were statistically no different after adjustment, reported Anthony Bai, MD, MSc, of Queen’s University in Kingston, Ontario, and coauthors in CHESTopens in a new tab or window.

EAC antibiotics were in fact associated with more harm than good: Clostridioides difficile colitis was seen in 0.2% or less of the LAC patient population and 0.8-1.1% of the EAC population, a 1% risk difference after adjustment (95% CI 0.3-1.7).

The present study supports skipping anaerobic coverage for aspiration pneumonia and relying on ceftriaxone or levofloxacin alone, Bai and colleagues concluded. They noted that the findings from their relatively large study, counting nearly 4,000 people, are consistent with previous studies while specifically including only patients receiving first-line antibiotics.

“Hopefully, this study will promote further adoption of the most recent guidelines relating to aspiration pneumonia, with resultant improvement in patient care, specifically decreased risk of side effects (C. difficile colitis), and potentially decreased antibiotic resistance in the community,” commented Mark Yoder, MD, of Rush University Medical Center in Chicago, who was not involved in the research.

In 2019, despite the absence of strong trial-level evidence, the American Thoracic Society and Infectious Diseases Society of America released guidelines that did not recommend routinely giving anaerobic coverageopens in a new tab or window to patients with aspiration pneumonia. The guidelines instead endorsed first-line antibiotics, like ceftriaxone or levofloxacin, for general treatment of patients with community-acquired pneumonia (CAP).

Indeed, the Canadian study showed a steady increase of aspiration pneumonia patients getting LAC antibiotics from 2015 to 2021.

“We have generally changed our practice accordingly and recommended against routine anaerobic coverage for CAP due to the risks of C. difficile infection and the need to avoid unnecessarily broad antibiotic use,” said Rebekah Moehring, MD, MPH, of Duke University in Durham, North Carolina, who was not involved in the study. “We routinely face antibiotic resistance scenarios in our practice and thus a lot of emphasis has been placed on judicious use of antibiotics.”

The study authors noted that antibiotic coverage for aspiration pneumonia “has been debated and changed over time” and that historically, anaerobic bacteria were thought to be the predominant pathogen.

Yoder and Bai’s group both emphasized that anaerobic bacteria are isolated in only a minority of cases of aspiration pneumonia nowadays.

“Conceptually, almost all cases of pneumonia are due to aspiration of bacteria colonizing the oropharynx (mouth and throat), and the treatment of community-acquired as well as hospital-acquired and ventilator-associated pneumonia does not routinely include coverage of anaerobic pathogens,” Yoder told MedPage Today via email.

The study included 3,999 consecutive adults hospitalized for aspiration pneumonia at 18 acute care hospitals in Ontario from 2015 to 2022. An ICD diagnosis code was used to search records of pneumonitis due to food and vomit including aspiration pneumonia not otherwise specified, or due to food, gastric secretions, milk, or vomit.

Bai and colleagues split participants into LAC (67.1%) and EAC (32.9%) groups based on the initial antibiotic they received within 2 days of admission. Ceftriaxone, cefotaxime, and levofloxacin counted as LAC; amoxicillin-clavulanate, moxifloxacin, metronidazole, and clindamycin were defined as EAC.

Baseline characteristics were well balanced between the two treatment groups. The patient population was approximately 40% women, and the average age was about 80 years old. Fewer than a fourth of patients were from long-term care facilities.

Among the most commonly used antibiotics were ceftriaxone, metronidazole, moxifloxacin, and macrolides.

Median length of stay was 6.7 days in the LAC group and 7.6 days in the EAC group. Among patients discharged alive, 18.5% of the LAC group and 18.3% of the EAC group were readmitted to the hospital within 30 days.

The investigators acknowledged that their database did not capture cases of aspiration pneumonitis that did not require antibiotic treatment. Other study limitations included the inability to count deaths or any C. difficile colitis diagnoses after hospital discharge.

“The avoidance of unnecessary antibiotic can decrease the risk of antibiotic adverse effects, especially C. difficile colitis,” Bai’s team nonetheless noted. “On a larger scale, limiting unnecessary antibiotic use may lower antibiotic selective pressure and result in less antibiotic resistance. In hospitals, antimicrobial stewardship programs can implement targeted interventions to de-escalate antibiotic therapy for aspiration pneumonia.”

Sublingual Acute Stroke Neuroprotectant Dazzles in Phase III Trial

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Experts raise concerns about analysis and reporting in Chinese studyShare on Facebook. Opens in a new tab or window

A computer rendering of a brain with a dark spot on the side

For acute ischemic stroke within 48 hours of onset, the novel sublingual combination of edaravone (Radicava) with dexborneol appeared to dramatically improve functional outcomes in the phase III TASTE-SL trial from China.

The chance of a good functional outcome as marked by a modified Rankin Scale (mRS) score of 0-1 on day 90 was 50% improved with the neuroprotectant compared with placebo (64.4% vs 54.7%, OR 1.50, 95% CI 1.15-1.95, P=0.003), reported Dongsheng Fan, MD, of Peking University Third Hospital in Beijing, and colleagues in JAMA Neurologyopens in a new tab or window.

Adverse events (AEs) occurred in most patients in both groups; serious AEs were uncommon and balanced between the two.

“This is a remarkable result, and given that edaravone dexborneol is low cost, simple to administer (even in patients who are unconscious, disabled, or dysphagic), and readily available in China, it has major potential practice implications,” said Craig S. Anderson, PhD, and Lili Song, MD, PhD, both of the George Institute for Global Health in Sydney.

In an accompanying editorialopens in a new tab or window, they acknowledged the “litany of failed neuroprotection trials in acute ischemic stroke” over after several decades of considerable investment but noted a “clear rationale” for adjuvant stroke treatment in the endovascular treatment era.

“Many patients have poor access to reperfusion therapy and, even when they do have it, do not have a satisfactory recovery despite achieving a good technical result of recanalization of an occluded vessel. Moreover, in showing the benefits of endovascular therapy within a 6- to 24-hour onset-to-treatment time window in patients with a large ischemic lesion, recent trials have also challenged understanding about how viable vs dead neuronal tissue is defined on brain imaging,” they wrote.

Edaravone is a low-molecular-weight drug that appears to protect neurons, glia, and vascular endothelial cells against oxidative stress and inflammation. It is FDA approved for amyotrophic lateral sclerosis. The combination with dexborneol, a component of proprietary Chinese medicine, “is believed to offer a synergistic action,” the editorialists noted.

However, they pointed out some serious concerns with the results: “To begin with, the size of the observed treatment effect … is much higher than would be expected of a neuroprotective agent. Because approximately half of the patients commenced the treatment at 24 hours or longer after symptom onset, this size of benefit is equivalent to that seen with intravenous thrombolysis initiated within the first few hours of an acute ischemic stroke. Therefore, the results challenge our understanding of the ‘time is brain’ concept of the evolving ischemic penumbra and are contrary to the neutral results of the ESCAPE-NA1 trialopens in a new tab or window, and most recently ESCAPE-NEXTopens in a new tab or window … which evaluated nerinetide, a highly promising drug that attenuates excitotoxic cell death.”

The editorialists suggested chance could be at play in TASTE-SL, which was powered at 80% rather than a more conventional 90% and did not show benefits of edaravone dexborneol in any secondary endpoints, including early neurological impairment in NIH Stroke Scale (NIHSS) scores between baseline and 14 and 30 days.

“It is unfortunate that no ancillary measures of health-related quality of life were collected during follow-up to allow a broader appraisal of the recovery of patients,” Anderson and Song lamented.

The researchers, though, chalked the nonsignificant secondary endpoint results up to the substantial number of mild strokes in the trial, with an average NIHSS score of 7.

The trial included 914 patients, ages 18-80 years, who had an NIHSS score of 6-20; a total motor deficit score of the upper and lower limbs of 2 or greater; clinically diagnosed acute ischemic stroke symptoms within 48 hours; and a pre-stroke mRS score of 1 or less.

They were randomly assigned to sublingual edaravone dexborneol (30 and 6 mg, respectively) or placebo comprised of inert dexborneol (60 μg, to simulate the taste of the active drug) twice daily for 14 days.

Limitations included exclusion of a patient who got endovascular thrombectomy and enrollment of only persons of Chinese ethnicity.

The editorialists also pointed to another limitation: “Just before being unblinded to the data toward the end of the study, the steering committee made the decision to use a complex approach to addressing missing primary outcome data in the primary analysis rather than a more conventional complete case analysis of the primary outcome. This included using the last observation carried forward or assigning a worse-case variable (6 for death) in patients with a missing outcome. Given that missingness (loss to follow-up) is invariably not lost at random, this could have influenced the result. Inevitably, this did not occur as they were readily confirmed in secondary imputation, covariate-adjusted, and subsequent complete case analyses.”

They also raised the specter of conflicts of interest, as the study authors included employees of three pharmaceutical companies, “including the one that sponsored the study and would naturally have an interest in the trial outcome.”

Furthermore, Anderson and Song added to the call for replication of the results in other regions of the world.

“Because maximizing access to reperfusion treatment is at the forefront of modern stroke services, and disease and social reasons for delayed presentation after symptom onset differ across regions, the TASTE-SL results are promising but less relevant to contemporary clinical practice outside of China,” they wrote. “However, they provide a clear justification for further evaluations of edaravone dexborneol in other populations, and for individual patient data meta-analysis to be undertaken to determine the totality of the evidence.”

“The performance bar is set high, but the benefits offered by safe treatments with only modest effects in reducing the burden of acute ischemic stroke worldwide are considerable,” Anderson and Song stated.

Magnesium Sulfate vs Fentanyl: The Future of Spinal Analgesics

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A new study found that intrathecal fentanyl and magnesium sulfate can effectively enhance spinal anesthesia, offering prolonged pain relief and sensory blockade

While fentanyl led to a faster onset, both provided similar durations of analgesia. This highlights the potential of utilizing natural, safe compounds like magnesium for effective pain management while avoiding risky substances like opioids.1

A new randomized controlled trial published in the Asian Journal of Anesthesiology uncovered important implications for utilizing natural mineral compounds as adjunct medications alongside anesthesia for improved healing outcomes.2 Their findings highlight the feasibility of incorporating holistic and integrative approaches within conventional medical settings.

The Dangers of Opioids

While the opioid fentanyl is commonly used to intensify and extend spinal blocks, its use risks life-threatening side effects and tremendous addiction potential. Overdose deaths linked to prescribed and illicit fentanyl have risen over 1,600% in recent years as the drug epidemics continue to intensify across North America.3 Even minor exposure can lead to risky dependencies given fentanyl’s potency level thousands times higher than morphine.4 There is an urgent need for safer alternatives capable of meeting patient analgesic needs without fueling the ongoing crisis.  

Putting Magnesium to the Test

The study, led by Richa Richa and colleagues at the Department of Anesthesiology in India, aimed to analyze the efficacy of intrathecal magnesium sulfate versus fentanyl as an additive to spinal bupivacaine anesthesia.5 They measured impacts on the onset and duration of sensory and motor nerve blocks, along with effects on circulatory vital signs.

100 patients scheduled for elective infraumbilical surgical procedures were randomly divided into two equal groups. Under strict aseptic precautions, Group 1 received hyperbaric bupivacaine combined with 25μg fentanyl, while Group 2 was administered bupivacaine with 100mg magnesium sulfate instead.6

The results proved illuminating. While fentanyl led to more rapid nerve blockade, magnesium matched its capacities for prolonging spinal anesthesia without concerning side effects.7 As the authors conclude, non-opioid magnesium shows promise as an alternative adjuvant for improving pain relief after surgery.8

An Affordable and Sustainable Solution

Not only could this simple mineral salt transform patient outcomes through effective analgesia, but alleviating reliance on habit-forming opioids offers immense societal benefits in tackling addiction epidemics. And unlike costly medications still under patent protection, magnesium is an affordable, readily available compound whose production can be sustainably scaled.9

Integrating such natural healing modalities aligns clinical practice with principles of environmental sustainability, social responsibility, and global health equity. It highlights the vast overlooked potential around traditionally used supplements for improving wellbeing across all populations.

COVID-19- and Flu-Ravaged Lungs Could Be Repaired with mRNA Therapy

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Ravaged Lungs Could Be Repaired with mRNA Therapy

Infection in lungs

Respiratory infections, such as those caused by SARS-CoV-2 or influenza, can damage the lungs’ delicate network of capillary blood vessels, compromising oxygen delivery and carbon dioxide removal. To overcome this damage, the lungs depend on the regenerative capacities of vascular endothelial cells. As valuable as these cells are, they can, according to University of Pennsylvania scientists, benefit from a little help.

The scientists, led by Andrew Vaughan, PhD, focused on a repair pathway involving vascular endothelial growth factor α (Vegfa) and the TGF-β receptor 2 (TGF-βR2). Using animal models and human tissue samples, the scientists showed that delivering Vegfa via lipid nanoparticles (LNPs) greatly enhances modes of repair for damaged blood vessels.

Details were published recently in Science Translational Medicine, in an article titled, “TGF-βR2 signaling coordinates pulmonary vascular repair after viral injury in mice and human tissue.”

“Mice deficient in endothelial Tgfbr2 exhibited prolonged injury and diminished vascular repair,” the article’s authors wrote. “Loss of endothelial Tgfbr2 prevented autocrine Vegfa expression, reduced endothelial proliferation, and impaired renewal of aerocytes thought to be critical for alveolar gas exchange.”

“We developed a lipid nanoparticle that targets the pulmonary endothelium, Lung-LNP (LuLNP),” the authors continued. “Delivery of Vegfa mRNA, a critical TGF-βR2 downstream effector, by LuLNPs improved the impaired regeneration phenotype of endothelial cell Tgfbr2 deficiency during influenza injury.”

Vaughan’s team and other investigators had previously shown that endothelial cells are among the unsung heroes in repairing the lungs after viral infections. But Vaughan’s team noted that its work demonstrated that a “more granular understanding of the fundamental mechanisms driving reconstitution of lung endothelium” could inform efforts to facilitate therapeutic vascular repair.

“Here we’ve identified and isolated pathways involved in repairing this tissue, delivered mRNA to endothelial cells, and consequently observed enhanced recovery of the damaged tissue,” Vaughan said. “These findings hint at a more efficient way to promote lung recovery after diseases like COVID-19.”

The team found Vegfa’s involvement in this recovery, while building on work in which they used single-cell RNA sequencing to identify TGF-βR2 as a major signaling pathway. The researchers saw that when TGF-βR2 was missing, it stopped the activation of Vegfa. This lack of signal made the blood vessel cells less able to multiply and renew themselves, which is vital for the exchange of oxygen and carbon dioxide in the tiny air sacs of the lungs.

“We’d known there was a link between these two pathways, but this motivated us to see if delivering Vegfa mRNA into endothelial cells could improve lung recovery after disease-related injury,” said first author Gan Zhao, PhD, a postdoctoral researcher in the Vaughan laboratory.

The Vaughan laboratory then reached out to Michael J. Mitchell, PhD, of the School of Engineering and Applied Science, whose laboratory specializes in LNPs, to see if delivery of this mRNA cargo would be feasible.

“LNPs have been great for vaccine delivery and have proven incredibly effective delivery vehicles for genetic information,” said Mitchell, who is an associate professor of bioengineering at Penn Engineering and a co-author of the paper. “But the challenge here was to get the LNPs into the bloodstream without them heading to the liver, which is where they tend to congregate as its porous structure lends favor to substances passing from the blood into hepatic cells for filtration. So, we had to devise a way to specifically target the endothelial cells in the lungs.”

The Mitchell laboratory’s LNPs proved effective in delivering Vegfa into endothelial cells, and as a result, the researchers saw a marked improvement in vascular recovery in their animal models. Within the animal models, the researchers saw improved oxygen levels, and in some, the treatment helped them recover their weight better than the control group. These treated mice also had less lung inflammation, shown by lower levels of certain markers in their lung fluid, and their lungs showed less damage and scarring, with more healthy blood vessels.

“We’re looking forward to testing this delivery platform for other cell types in the lung, and it will be important to evaluate whether TGF-βR2 signaling is important in other injury contexts including chronic conditions like emphysema and chronic obstructive pulmonary disease,” Vaughan said. “With this proof-of-concept being well validated, we’re sure that we’ll pave the way for new mRNA-based strategies for treating lung injury.”

Molecular Glue May Cement a Path to Novel Cancer Treatments.

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Proteins

Research led by the Centre for Targeted Protein Degradation (CeTPD) in the University of Dundee identified a breakthrough class of molecular glue that could pave the way for a new generation of drugs to target cancers and neurodegenerative diseases. The researchers collaborated with the research group of Georg Winter, PhD, at the Research Center for Molecular Medicine (CEMM) of the Austrian Academy of Sciences in Vienna, and have defined a new class of so-called “intramolecular bivalent glue,” which binds proteins that would otherwise stay apart.

The findings are published in Nature in an article titled, “Targeted protein degradation via intramolecular bivalent glues.”

“Targeted protein degradation is a pharmacological modality that is based on the induced proximity of an E3 ubiquitin ligase and a target protein to promote target ubiquitination and proteasomal degradation,” wrote the researchers. “This has been achieved either via proteolysis-targeting chimeras (PROTACs)—bifunctional compounds composed of two separate moieties that individually bind the target and E3 ligase, or via molecular glues that monovalently bind either the ligase or the target. Here, using orthogonal genetic screening, biophysical characterization, and structural reconstitution, we investigate the mechanism of action of bifunctional degraders of BRD2 and BRD4, termed intramolecular bivalent glues (IBGs), and find that instead of connecting target and ligase in trans as PROTACs do, they simultaneously engage and connect two adjacent domains of the target protein in cis.”

“These findings have major implications for the entire pharmaceutical industry engaged in targeted protein degraders,” said Alessio Ciulli, PhD, director of Dundee’s CeTPD.

“This is particularly true for the development of drugs that target cancer, neurodegenerative diseases, and many more illnesses driven by proteins that have always been considered undruggable.

“The glue that we have been able to define is special because it first attaches itself to one protein in two places—not just one—and then recruits the second protein, effectively sandwiching the two proteins together. We have only been able to identify this using our Targeted Protein Degradation technology and have identified a vulnerability that can be exploited by the design of new drugs that could potentially transform treatment for cancer patients, and those with other untreatable diseases.”

Targeted protein degradation (TPD) is an emerging field of drug development for treating diseases that involves redirecting protein recycling systems in our cells to destroy disease-causing proteins.

Working with collaborators at CEMM, the Goethe University of Frankfurt, and Eisai, the Japanese pharmaceutical company, the Dundee team has been able to reveal a novel mechanism of molecular gluing, different from those previously known.

The new mechanism binds to two sides of the target protein instead of just one, prompting a rearrangement of the whole protein and stabilizing its previously unknown interaction with the E3 ligase. The team was able to visualize, for the first time, the precise mechanism by which their compounds work and bring together the target proteins to one of these E3 ligases. Because the molecules have two heads, which latch on to two different regions within the same target protein, these have been coined intramolecular bivalent glues.

“The impact of what we have revealed here cannot be underestimated,” added Ciulli.

“This will cause a ripple effect throughout the pharmaceutical industry and has the potential to transform how we view drug development.”

Novel Autoimmune Disease Triggered Uncovered.

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One of the mysteries of immunology: the function of B cells (green) in the thymus gland was previously unknown. Researchers have now been able to show that the immune cells help to prevent T cells from attacking the body. [Jan Böttcher, Thomas Korn / TUM]

Researchers from the Technical University of Munich (TUM) and the Ludwig Maximilian University of Munich (LMU) have discovered that the immune cells known as B cells contribute to the “training” of the T cells in the thymus gland. If this process fails, autoimmune diseases can develop.

The findings are published in Nature in an article titled, “B cells orchestrate tolerance to the neuromyelitis optica autoantigen AQP4.”

“Neuromyelitis optica is a paradigmatic autoimmune disease of the central nervous system, in which the water-channel protein AQP4 is the target antigen,” the researchers wrote. “The immunopathology in neuromyelitis optica is largely driven by autoantibodies to AQP42. However, the T cell response that is required for the generation of these anti-AQP4 antibodies is not well understood. Here we show that B cells endogenously express AQP4 in response to activation with anti-CD40 and IL-21 and are able to present their endogenous AQP4 to T cells with an AQP4-specific T cell receptor (TCR).”

The team was led by Thomas Korn, PhD, professor of experimental neuroimmunology at TUM and a principal investigator in the SyNergy Cluster of Excellence, and Ludger Klein, PhD, professor of immunology at LMU’s Biomedical Center (BMC).

Neuromyelitis optica is an autoimmune disease similar to multiple sclerosis (MS). While it is not yet known which molecules are attacked in MS, it is well-established that T cells respond to the protein AQP4 in neuromyelitis optica. AQP4 is most prominently expressed in cells of the nervous tissue, which then becomes the target of the autoimmune reaction. Frequently, the optic nerve is affected.

The researchers were able to show that in the thymus gland of humans and mice not only the epithelial cells but also B cells express and present AQP4 to the T cell precursors. If the B cells were prevented from doing so in animal experiments, AQP4-reactive T cell precursors were not eliminated and the autoimmune disease developed. This was also the case when the epithelial cells still presented the molecule. The team concludes from this that B cells in the thymus are a necessary condition for immune tolerance regarding AQP4.

“We suspect that this previously unknown process has evolved particularly to prevent dangerous interactions between autoreactive T and B cells in the lymph nodes and spleen, the so-called peripheral immune compartment,” explained Klein. Once the immune system is developed, B and T cells can communicate and thus trigger highly effective immune reactions. This is useful when it comes to fighting pathogens quickly. On occasion, however, B cells may accidentally present the body’s own proteins, such as AQP4. If the T cells that react to AQP4 had not been sorted out in the thymus, this could lead to a sudden and violent large-scale attack on the body.

“We assume that problems with the training of T cells by the B cells in the thymus can cause other autoimmune diseases as well,” said Korn. “After all, the B cells in the thymus present a whole range of the body’s own proteins. The corresponding interactions must be investigated in further studies.”

According to the researchers, likely suspects include antiphospholipid syndrome (APS) and certain forms of cerebral amyloid angiopathy. “Looking further into the future, this interaction in the thymus might be exploited to treat existing autoimmune diseases in a very targeted manner,” said Korn.