Latest news with #Immunity
The Hindu
12 hours ago
- Health
- The Hindu
Immune cells' fat blocks brain's ability to clean Alzheimer's plaques
Alzheimer's disease is a progressive brain disorder and a form of dementia that affects memory, thinking, and behaviour. As symptoms become more severe, the disease can seriously affect a person's ability to perform tasks that would otherwise be deemed routine, like brushing teeth, making a meal or even recognising family members. For many years, the leading theory has been that Alzheimer's is caused when two harmful proteins called amyloid-beta and tau accumulate in the brain. This pile-up sets off a chain of events, eventually damaging nerve cells and leading to memory loss, confusion, and mood changes. This destruction doesn't happen overnight. It begins years, even decades before symptoms appear. In 2021, an estimated 57 million people worldwide were affected by dementia, with Alzheimer's contributing to 60-70% of the cases. Currently, there is no cure for Alzheimer's but there are treatments that can slow symptoms and improve quality of life. It isn't surprising that in the ongoing search for answers, scientists are increasingly turning their attention from neurons to their lesser-known but equally critical neighbours: microglia, the brain's resident immune cells. In a new study published in Immunity, researchers led by Gaurav Chopra at Purdue University have uncovered how fat metabolism in microglia may be a key driver of disease progression. 'This study is pretty interesting and part of a growing body of studies indicating the role of fat metabolism problems in cells around amyloid plaques,' Indian Institute of Science professor Deepak Nair said. The lipid link In healthy brains, microglia serve as surveillance cells, clearing away waste products and toxic proteins like amyloid-beta (Aβ), the sticky molecule that forms the hallmark plaques in Alzheimer's. This clean-up process helps protect neurons from damage. But in Alzheimer's patients this mechanism fails. 'The big question was: how and why are microglia no longer able to eat up or clear these plaques?' said Priya Prakash, a co-lead author of the paper. 'This isn't a new observation. Dr. Alzheimer himself noted fat vacuoles in glial cells over a century ago, but their functional significance has remained unclear until now.' The study identified DGAT2, an enzyme that converts free fatty acids into triacylglycerols (TAGs), the main component of lipid droplets, as a key player. In both mouse models and post-mortem human brain samples from patients with late-stage Alzheimer's, the researchers found that microglia near amyloid plaques have high DGAT2 expression and are bloated with lipid droplets, particularly in the hippocampus, the region responsible for memory. 'We see that the proximity of microglia to plaques correlates with lipid droplet size. The closer they are, the fatter they get,' Prakash noted. What causes the lipid overload? According to the study, Aβ exposure triggers a metabolic chain reaction. Microglia start converting free fatty acids into fats stored inside lipid droplets. Over time, this lipid build-up disrupts their ability to engulf and digest more Aβ, setting up a vicious cycle: more plaques lead to more fat, which leads to more dysfunction. The research team used advanced imaging, lipidomic analysis, and metabolomics to track how microglia's lipid profiles changed over time in response to Aβ exposure. Initially, microglia accumulated toxic free fatty acids. Later, with the help of the DGAT2 enzyme, they converted these fatty acids into triacylglycerols and stored them in lipid droplets. To test whether this lipid build-up could be reversed, the researchers used genetically engineered mice that mimicked human Alzheimer's, known as 5xFAD mice. Two methods were used to reduce DGAT2 activity: a pharmacological inhibitor, currently in clinical trials for non-alcoholic fatty liver disease, and a custom-designed PROTAC-like degrader that targets DGAT2 specifically in microglia. 'When we blocked DGAT2, we saw reduced fat accumulation in microglia and restoration of their ability to clear amyloid plaques. Even a one-week treatment in aged mice with heavy pathology drastically reduced the plaque burden by over 50% and significantly reduced neuronal damage markers,' Prakash said. However, Prof. Nair cautioned that the animal model used in this study is an accelerated Alzheimer's disease model that relies on Aβ pathology, so the findings may not be equally applicable to all forms or stages of the disease. A fat-filled puzzle Lipid droplets are not inherently bad. In fact, they help cells survive stress by safely storing excess fat. But in microglia that are chronically exposed to Aβ, this once-protective response turns harmful. The study's authors suggested that microglia sacrifice their protective immune function in exchange for lipid safety and that this trade-off may be a key step in Alzheimer's progression. The study also uncovered a notable sex-based difference: female mice accumulated more lipid droplets in their microglia and showed more severe microglial impairment than males. This echoed real-world data that show women face a higher risk of developing Alzheimer's. Because DGAT2 is expressed in many cell types throughout the body, targeting it systemically could lead to unwanted side effects. The team's microglia-specific degrader represents an early but promising step towards cell-selective therapy. 'This is a beautiful proof of concept,' Prof. Nair said. 'We've had over 100 drugs in clinical trials for Alzheimer's in the past 20 years, and very few have succeeded. The disease is complex in its origin — it's not caused by one thing.' While the amyloid cascade hypothesis has dominated the field for decades, more recent theories incorporate inflammation, tau protein tangles, metabolic dysfunction, and now, lipid metabolism. 'In brain diseases, homeostasis slowly breaks down until the system is overwhelmed,' Prof. Nair said. 'If we can control just three or four critical pathways, lipid metabolism being one of them, it might be enough to slow down that collapse. 'And slowing down matters. A five-year delay in Alzheimer's onset would significantly reduce the socioeconomic burden of the disease.' Manjeera Gowravaram has a PhD in RNA biochemistry and works as a freelance science writer.
Time of India
5 days ago
- Health
- Time of India
Hidden obesity is real: How one cookie a day can sabotage your gut health
That innocent-looking cookie, small pack of fries, or occasional cheeseburger might feel like a harmless indulgence—especially if you're otherwise eating healthy or don't struggle with your weight. But new research suggests these tiny treats could be doing silent, long-term damage to your gut—even in small doses. A recent Australian study published in the journal Immunity (May 2025) has found that just two days of eating a high-fat diet, mainly one rich in saturated fats, can disrupt gut defences and increase inflammation throughout the body. These are the same types of fats found in everyday favourites like muffins, deep-fried snacks, processed meats, and fast food. Silent inflammation starts with everyday fat The study, titled 'Acute exposure to high-fat diet impairs ILC3 functions and gut homeostasis', was led by Dr Cyril Seillet , a researcher from Monash University and The Walter and Eliza Hall Institute of Medical Research. Under this study, using mouse models, Dr Seillet and his team showed that a high-fat diet rapidly impairs the function of a specific group of immune cells known as ILC3s (group 3 innate lymphoid cells). These cells are vital for maintaining the gut's protective barrier, largely by producing a molecule called interleukin-22 (IL-22). by Taboola by Taboola Sponsored Links Sponsored Links Promoted Links Promoted Links You May Like Secure your family's future! ICICI Pru Life Insurance Plan Get Quote Undo IL-22 helps the gut produce antimicrobial peptides, mucus, and tight junction proteins that keep harmful bacteria and toxins from leaking into the bloodstream. When ILC3s can't produce enough IL-22, the gut lining becomes more permeable—a condition often described as 'leaky gut.' This allows inflammatory substances to seep into circulation, silently fueling long-term inflammation and increasing the risk of chronic disease. 'The more saturated fats we eat, the more inflammation that builds up,' said Dr Seillet. 'But this inflammation remains silent for years and only shows up later as chronic conditions.' Not all fats are equal: How saturated vs unsaturated fats impact your gut The study revealed that not all fats affect the gut the same way. Mice fed with saturated fats like palmitic acid, found in butter, fatty meats, and palm oil, experienced reduced IL-22 production and gut barrier breakdown. In contrast, those consuming unsaturated fats like oleic acid, which is found in olive oil and avocados, maintained healthier gut function. Saturated fats were found to trigger harmful fat oxidation pathways in immune cells, while unsaturated fats formed protective lipid droplets that preserved immune function. The effects were so immediate that even after just 48 hours, mice on a high-fat diet showed gut inflammation and immune suppression. By day seven, the changes became even more pronounced. Fatty foods damage gut bacteria, but your gut can heal The study also looked at the gut microbiome, the community of bacteria living in the intestines. Just one week of a high-fat diet caused dramatic shifts: beneficial bacteria declined, and harmful species flourished. Some of these bad actors, like Enterococcus gallinarum, are known to erode the gut lining and promote inflammation. To test how these dietary changes might affect disease recovery, researchers induced colitis in mice fed different diets. Those on high saturated-fat diets fared worse—losing more weight and showing greater gut damage—than mice fed unsaturated fats or regular food. What's encouraging is that these negative effects can be reversed. When mice returned to a standard, lower-fat diet, their gut function began improving within two days, and most immune functions returned to normal within a week. This suggests that the body can bounce back—if we catch the damage early and adjust our eating habits. Your gut remembers: How fatty foods leave a lasting impact Although the study was conducted in mice, similar effects were observed in cultured human immune cells, giving weight to the findings. This research may help explain why people experience digestive discomfort after periods of poor eating—like during holidays or fast-food binges. It also reinforces why obesity is now understood as a state of chronic, silent inflammation, often triggered and worsened by gut dysfunction. Experts say these findings could also be linked to rising rates of inflammatory bowel disease (IBD), autoimmune conditions, and metabolic disorders like diabetes and fatty liver disease—all of which have roots in gut health and inflammation. 'Even an occasional indulgence in high-fat foods can disrupt your gut if it's not balanced out with healthier choices,' said Dr Rakesh Kochhar , former head of gastroenterology at PGI Chandigarh, in response to the study. 'The key lies in using unsaturated fats and limiting ultra-processed snacks and fried foods.' You don't need to completely avoid fats; your body needs them. But the type of fat, how often you consume it, and what you pair it with matter greatly. The occasional cookie might seem harmless, but when such indulgences become regular, they quietly add up in ways that affect your gut, immune system, and overall health. In short, hidden obesity and inflammation can begin where you least expect it, in the snacks you don't think twice about. Your body can recover quickly with the right diet and lifestyle choices. That's a reason to rethink your next "harmless" bite. Also Read: Why asthma gets worse in monsoon and what you can do about It
Time of India
25-06-2025
- Health
- Time of India
Alzheimer's-delaying gene variant works by suppressing brain inflammation, study finds
New Delhi: A rare gene variant known to delay the onset of Alzheimer's disease works by suppressing inflammation in the brain's immune cells, a new study states. The findings, published in the journal Immunity, support the notion that inflammation in the brain is a major driver of neurodegenerative, or ageing-related disorders, researchers, including those from Weill Cornell Medicine, US, said. In Alzheimer's disease, one's memory, thought processes, and decision-making steadily decline, eventually affecting daily routine activities. A permanent change in the DNA of a gene, which can occur over time and be passed down generations, results in a 'gene variant' -- not all of them produce a harmful effect. The team found that the gene variant 'APOE3-R136S' rendered protection against Alzheimer's disease by blocking an inflammation process 'cGAS-STING', known to be part of one's innate immune system, and abnormally triggered in neurodegenerative diseases. One is born with an innate immune system, which is the body's first line of defense against diseases. It does not rely on exposure to disease-causing bacteria or fungi to learn how to fight infections. Blocking the brain's inflammation process through drugs was found to produce protective effects due to the gene variant -- also called the ' Christchurch mutation ' -- in a preclinical model (used before proceeding to clinical trials). "This is an exciting study because it suggests that inhibiting this cGAS-STING pathway could make the brain more resistant to the Alzheimer's process, even in the face of significant tau accumulation ," senior author Li Gan, a professor in neurodegenerative diseases at Weill Cornell Medicine, said. A hallmark feature of a brain affected by Alzheimer's is the clumping up of tau proteins -- essential for maintaining a brain cell's structure and function, but abnormal changes can cause an accumulation. The development of drugs targeting clumps of tau is a common target for developing drugs against the disorder. The Christchurch mutation gene is important in protecting against this mechanism of tau proteins from clumping up, potentially preventing cognitive decline, the researchers said. For the study, the team engineered the Christchurch mutation into the APOE gene in mice with tau accumulation and found that the gene variant protected the animals from hallmark features of Alzheimer's -- including tau accumulation, damage to connections of brain cells, and disrupted activity. The protective effects were traced to suppression of the cGAS-STING pathway, which is triggered normally against a viral infection, but chronically in Alzheimer's disease, the researchers said. "We are particularly encouraged that this mutation ameliorates disease at the level of brain function, which has not been shown before," the first author on the study, Sarah Naguib, Weill Cornell Medicine said. Studies have also suggested that manipulating the Christchurch mutation gene itself -- through gene therapy -- can offer protection against Alzheimer's disease.
Leader Live
29-05-2025
- Health
- Leader Live
Lush Smoothie in Buckley to focus on health and wellbeing
In 2020, under the covid pandemic, Kat Jones launched Aspire to Inspire mobile fitness company. Over 12 months later, she opened a women's-only gym by the same name, in Buckley town centre. The Aspire to Inspire 24-hour gym now has 190 members. This weekend the 40-year-old, who is also a menopause coach, is opening her latest venture, Lush Smoothie. Read more: Flintshire business with prom 2026 in its sights! Located upstairs above Aspire to Inspire on Brunswick Road, the smoothie bar will have natural goodness at its heart. Kat said: "It's about promoting health and wellbeing, offering a healthier alternative to the people of Buckley. "It is all made fresh, using natural products, and can be tailored to individual requirements too, such as no nut products. "As well as fresh fruits and vegetables, we have collagen, a variety of honeys and selection of milks. Read more: 'We're humbled' - Meet the winner of best deli, butchers, farm shop 2025 "We hope to bring some seasonal editions to the menu throughout the year too." As well as the smoothies, such as Detox Delight (spinach, apple, celery, lemon and ginger) and Hormone Harmony (mixed berries, Greek yoghurt, chia seeds, maca powder and coconut water), Lush Smoothie will offer 'wellness shots', including Immunity (carrot, ginger, turmeric, pepper and orange). Over a series of feedback from taster events, Kat has managed to help pin down recipes that have great flavours and texture, as well as offering value for money. Lush Smoothie, which includes 'chill space' area with seating, opens officially on Saturday (May 31) at 8am.
Toronto Sun
27-05-2025
- Business
- Toronto Sun
CHARLEBOIS: Crumbs of justice in Canada's biggest bread scam
Though a $500-million class-action settlement has been approved, the story is far from over Sliced white bread. Photo by File Photo / Getty Images Canada's bread price-fixing scandal stands as one of the most damaging and far-reaching corporate breaches of trust in the country's food retail history. The recent approval of a $500-million class-action settlement by an Ontario court marks a significant, if partial, step toward accountability. But the story is far from over. This advertisement has not loaded yet, but your article continues below. THIS CONTENT IS RESERVED FOR SUBSCRIBERS ONLY Subscribe now to read the latest news in your city and across Canada. Unlimited online access to articles from across Canada with one account. Get exclusive access to the Toronto Sun ePaper, an electronic replica of the print edition that you can share, download and comment on. Enjoy insights and behind-the-scenes analysis from our award-winning journalists. Support local journalists and the next generation of journalists. Daily puzzles including the New York Times Crossword. SUBSCRIBE TO UNLOCK MORE ARTICLES Subscribe now to read the latest news in your city and across Canada. Unlimited online access to articles from across Canada with one account. Get exclusive access to the Toronto Sun ePaper, an electronic replica of the print edition that you can share, download and comment on. Enjoy insights and behind-the-scenes analysis from our award-winning journalists. Support local journalists and the next generation of journalists. Daily puzzles including the New York Times Crossword. REGISTER / SIGN IN TO UNLOCK MORE ARTICLES Create an account or sign in to continue with your reading experience. Access articles from across Canada with one account. Share your thoughts and join the conversation in the comments. Enjoy additional articles per month. Get email updates from your favourite authors. THIS ARTICLE IS FREE TO READ REGISTER TO UNLOCK. Create an account or sign in to continue with your reading experience. Access articles from across Canada with one account Share your thoughts and join the conversation in the comments Enjoy additional articles per month Get email updates from your favourite authors Don't have an account? Create Account The scheme, which ran from 2001 to 2015, involved deliberate coordination between retailers and suppliers to raise the price of packaged bread — a basic household staple. Companies named in the lawsuit include Loblaw, its parent company George Weston Ltd., Metro, Sobeys, Walmart, and Giant Tiger. The impact on consumers was severe. Some estimates suggest Canadians were overcharged by more than $5 billion over the 14-year period. The cost was buried in weekly grocery bills, unnoticed by many, but cumulatively staggering — especially for lower-income households who spend a greater share of their income on food. The Competition Bureau launched its investigation in 2015 when Loblaw came forward as a whistleblower under its Immunity and Leniency Program. In exchange for cooperating with investigators, Loblaw and George Weston received immunity from criminal prosecution. Their decision to self-report triggered years of legal scrutiny and public outrage. In 2017, the companies attempted to mitigate damage by offering $25 gift cards to 3.8 million Canadians who did apply for a card — a gesture that cost them $96 million and was widely seen as insufficient. Your noon-hour look at what's happening in Toronto and beyond. By signing up you consent to receive the above newsletter from Postmedia Network Inc. Please try again This advertisement has not loaded yet, but your article continues below. More recently, in 2023, Canada Bread pleaded guilty and paid a record $50-million fine for its role in the price-fixing arrangement. The violations occurred while the company was owned by Maple Leaf Foods, but it was Grupo Bimbo, which acquired Canada Bread in 2014, that accepted responsibility and cooperated with regulators — a rare display of corporate accountability in a case marked by silence from many involved. Despite multiple companies being named in the investigation, only Loblaw, George Weston, and Canada Bread have admitted guilt. No public sanctions or fines have been imposed on the others. Walmart, Metro, Sobeys, and Giant Tiger — all implicated by Loblaw — have denied the allegations. And yet, the investigation remains ongoing nearly a decade later. Ten years! This advertisement has not loaded yet, but your article continues below. Still, this imbalance in accountability has fuelled public frustration. Many Canadians feel that only those who came forward have faced consequences, while others remain untouched. Or perhaps the four remaining accused grocers were thrown under the proverbial bus by Loblaw in a calculated move to preserve its own reputation? RECOMMENDED VIDEO The $500-million class-action settlement — $404 million of which will come again from Loblaw and George Weston — was approved earlier in May by an Ontario judge who deemed it 'fair, reasonable, and in the best interests of class members.' The remaining $96 million is accounted for through the earlier gift card program. So, the money yet to be disbursed equals about $13 per Canadian adult, that's it. After legal fees and administrative costs, 78% of the remaining funds will go to eligible Canadians outside Quebec, with 22% reserved for Quebecers pending a court hearing on June 16. This advertisement has not loaded yet, but your article continues below. Yet for many, despite the apologies, the monetary settlement does little to restore trust. The scandal exposed deep vulnerabilities in Canada's food retail system: Weak competition laws, limited price transparency, and inadequate deterrents for collusion. Investigations of this scale take years — often too many — and the damage to public trust lingers long after fines are paid. Bread is not just a commodity. It is symbolic of nourishment, affordability, and stability. The deliberate manipulation of its price is more than a violation of antitrust laws — it is a betrayal of consumer confidence. If this case is to serve as a turning point, it must lead to more than financial compensation. Stronger enforcement, faster investigations, and greater transparency in pricing practices are needed. Without systemic reform, Canadians remain vulnerable to the next coordinated 'market adjustment' — buried in plain sight on store shelves. — Dr. Sylvain Charlebois is the Director of the Agri-Food Analytics Lab at Dalhousie University and co-host of The Food Professor Podcast Columnists Sunshine Girls Sunshine Girls Relationships Columnists
