Stories with Tag epigenetics

• Adipose tissue retains an epigenetic memory of obesity after weight loss

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  Posted: 2025-04-14 04:47:51

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  Even after successful weight loss, adipose tissue retains an "epigenetic memory" of prior obesity. This study found that specific DNA methylation patterns associated with obesity persist in fat cells even after individuals return to a healthy weight. These persistent epigenetic marks are linked to an increased risk of regaining weight and developing obesity-related metabolic complications like type 2 diabetes. This suggests that previous obesity leaves a lasting molecular imprint on fat tissue, potentially contributing to the difficulty of maintaining weight loss and highlighting the importance of early obesity prevention.

  This Nature publication, titled "Adipose tissue retains an epigenetic memory of obesity after weight loss," delves into the intricate mechanisms by which the body's fat tissue, also known as adipose tissue, preserves a molecular recollection of a prior obese state, even after successful weight reduction. This "epigenetic memory" resides not within the DNA sequence itself, but rather in the epigenome, a complex layer of chemical modifications to DNA and associated proteins that govern gene expression. The study meticulously examines how this persistent epigenetic signature influences the biology of adipose tissue and potentially contributes to the pervasive challenge of weight regain commonly experienced by individuals who have lost weight.

  The researchers employed a sophisticated array of techniques, including chromatin immunoprecipitation sequencing (ChIP-seq) and RNA sequencing, to comprehensively map the epigenetic landscape and gene expression profiles of adipose tissue in both mice and humans who had experienced weight loss. Their findings revealed that specific regions of the genome within adipose tissue retained distinct epigenetic marks, particularly alterations in histone modifications, which were established during the period of obesity and persisted even after weight reduction. These enduring epigenetic modifications were observed to be associated with altered expression of genes involved in crucial metabolic processes, including lipid metabolism, inflammation, and thermogenesis – the process of heat production in the body.

  Furthermore, the study provides compelling evidence that this epigenetic memory of obesity can functionally impact the behavior of adipose tissue. Specifically, the researchers demonstrated that the persistent epigenetic changes observed in formerly obese individuals were linked to an increased capacity for lipid storage and a diminished capacity for thermogenesis in adipose tissue. This suggests that the epigenetic memory established during obesity may predispose individuals to regain weight by promoting fat accumulation and hindering energy expenditure.

  The implications of this research extend beyond the immediate understanding of weight regain. By unveiling the molecular mechanisms underpinning the long-term effects of obesity on adipose tissue, the study paves the way for the development of novel therapeutic strategies aimed at disrupting this epigenetic memory. Such interventions could potentially hold the key to improving long-term weight management outcomes and mitigating the health risks associated with obesity. The authors posit that targeting these persistent epigenetic modifications may represent a promising avenue for preventing weight regain and enhancing metabolic health in individuals who have successfully lost weight. This research contributes significantly to the growing body of knowledge surrounding the complex interplay between genetics, epigenetics, and metabolic health, highlighting the enduring impact of obesity on the molecular landscape of adipose tissue.

  • Adipose Tissue
  • epigenetics
  • obesity
  • Weight Loss
  • Metabolic Memory
  • gene expression
  • DNA Methylation
  • Chromatin
  • Health
  • Biology
  • Medical Research
  • Disease

  Summary of Comments ( 172 )
  https://news.ycombinator.com/item?id=43678138

  Verbose tl;dr

  HN commenters discuss the implications of the study, with some focusing on the potential for future interventions to target this "epigenetic memory" to prevent weight regain. Several express skepticism about the novelty of the findings, pointing out that the difficulty of maintaining weight loss is well-known. Others highlight the study's focus on visceral fat, noting its particular relevance to metabolic health issues. Some question the relevance of the mouse model to humans and the long-term impact of the epigenetic changes. A few discuss the role of inflammation and other factors in obesity and weight regain. Finally, some commenters offer practical advice related to diet and exercise for weight management, even in light of the study's findings.

  The Hacker News post titled "Adipose tissue retains an epigenetic memory of obesity after weight loss" (linking to a Nature article) has generated several comments discussing the research and its implications.

  Several commenters focus on the implications for weight regain after weight loss. One commenter points out the frustrating cycle this creates for individuals who successfully lose weight, only to find themselves predisposed to regaining it. This commenter also raises questions about the efficacy and fairness of judging individuals based on their weight, given these biological predispositions. Another commenter expresses hope that this research will lead to better treatments targeting these epigenetic markers, making weight maintenance more achievable.

  The epigenetic nature of the "memory" is also a point of discussion. A commenter highlights the study's focus on DNA methylation as the mechanism for this memory. They also speculate about the evolutionary advantage of such a mechanism, suggesting it might have served to help individuals survive periods of famine.

  Another commenter questions the implications of the study on childhood obesity, pondering whether epigenetic changes from obesity during childhood might persist even longer than those acquired during adulthood.

  A few commenters delve into more specific aspects of the study. One discusses the role of inflammation in this epigenetic memory, citing another study on the subject. Another mentions the limitations of using mice as models for human obesity, while also acknowledging the value of animal models in this type of research. This commenter also raises the possibility that the epigenetic changes observed might be a consequence of obesity rather than a cause of weight regain.

  Finally, a commenter brings up the broader context of obesity research, noting the complexity of the issue and the multitude of factors involved. They suggest that while this study offers important insights into one aspect of obesity, it doesn't provide a complete picture. This commenter also cautions against oversimplifying the findings and emphasizes the need for further research.

• Violence alters human genes for generations, researchers discover

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  Posted: 2025-02-28 15:33:39

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  Research on Syrian refugees suggests that exposure to extreme violence can cause epigenetic changes, specifically alterations to gene expression rather than the genes themselves, that can be passed down for at least two generations. The study found grandsons of men exposed to severe violence in the Syrian conflict showed altered stress hormone regulation, even though these grandsons never experienced the violence firsthand. This suggests trauma can have lasting biological consequences across generations through epigenetic inheritance.

  A groundbreaking study conducted by researchers at the University of Florida, and published in the esteemed scientific journal PNAS, has revealed compelling evidence that experiences of extreme violence, specifically in the context of the ongoing Syrian conflict, can induce heritable changes in human gene expression that persist across multiple generations. This research focuses on the field of epigenetics, the study of heritable changes in gene activity that do not involve alterations to the underlying DNA sequence itself. Instead, epigenetic modifications influence how genes are "turned on" or "off," thereby affecting the production of proteins and ultimately influencing a wide range of biological processes and characteristics.

  The researchers meticulously examined DNA methylation patterns in Syrian refugee families residing in Jordan. DNA methylation, a prominent epigenetic mechanism, involves the addition of a methyl group to a DNA molecule, which can effectively silence gene expression. By comparing these patterns across three generations – grandparents who directly experienced the trauma of the Syrian conflict, their children who were exposed to the displacement and hardship resulting from the conflict, and their grandchildren born in the relative safety of refugee camps – the scientists were able to discern a distinct transgenerational epigenetic inheritance pattern.

  Specifically, the study identified alterations in DNA methylation within genes associated with stress response and mental health, including those linked to post-traumatic stress disorder (PTSD). These changes were observed not only in the individuals who directly endured the violence but also in subsequent generations who had not personally witnessed the conflict's brutality. This discovery suggests that the profound psychological and physiological impact of extreme trauma can be transmitted across generations, potentially predisposing descendants to heightened vulnerability to mental health challenges and other stress-related conditions.

  Furthermore, the study underscores the enduring biological consequences of violent conflict, demonstrating that the effects can extend far beyond the immediate victims and resonate through familial lineages. This research has profound implications for understanding the long-term health consequences of war and displacement, highlighting the need for comprehensive support systems and interventions not only for those directly affected by violence but also for future generations who carry the epigenetic scars of their ancestors' trauma. This pioneering work opens up new avenues for investigating the intricate interplay between environmental experiences, epigenetic modifications, and human health, paving the way for potential therapeutic strategies aimed at mitigating the transgenerational impact of trauma.

  • epigenetics
  • Genetics
  • intergenerational trauma
  • violence
  • Conflict
  • Syria
  • human health
  • gene expression
  • Mental Health
  • PTSD
  • Research
  • Science
  • DNA
  • heritable traits
  • long-term effects of violence

  Summary of Comments ( 205 )
  https://news.ycombinator.com/item?id=43206722

  Verbose tl;dr

  HN commenters were skeptical of the study's methodology and conclusions. Several questioned the small sample size and the lack of control for other factors that might influence gene expression. They also expressed concerns about the broad interpretation of "violence" and the potential for oversimplification of complex social and biological interactions. Some commenters pointed to the difficulty of isolating the effects of trauma from other environmental and genetic influences, while others questioned the study's potential for misinterpretation and misuse in justifying discriminatory policies. A few suggested further research with larger and more diverse populations would be needed to validate the findings. Several commenters also discussed the ethics and implications of studying epigenetics in conflict zones.

  The Hacker News post titled "Violence alters human genes for generations, researchers discover," linking to a University of Florida news article about a study on the epigenetic effects of violence in Syria, has generated several comments. Many commenters express skepticism and raise methodological concerns about the study.

  One recurring theme is the difficulty of isolating the effects of violence from other factors like poverty, malnutrition, and displacement, which often accompany conflict. Commenters argue that these confounding variables could also have significant epigenetic impacts, making it hard to attribute the observed changes solely to violence. Some suggest that the study should have included a control group experiencing similar hardships but not direct violence to better isolate the variable of interest.

  Another point of contention is the small sample size of the study. Several commenters point out that with a limited number of participants, the results might not be generalizable to the broader Syrian population or other populations affected by conflict. They call for larger-scale studies to validate the findings.

  Several commenters also critique the framing of the research and the news article. They argue that using terms like "altered genes" can be misleading to the public, as epigenetics involves changes in gene expression rather than alterations to the underlying DNA sequence. They worry that such phrasing could perpetuate misconceptions about the nature of inheritance and the immutability of genes.

  Some commenters question the causal link implied by the study. They point out that while the study shows a correlation between exposure to violence and epigenetic changes, it doesn't definitively prove that violence causes these changes. They suggest that the relationship could be more complex and involve other mediating factors.

  A few commenters raise concerns about the potential ethical implications of the research. They worry that linking violence to heritable epigenetic changes could lead to stigmatization or discrimination against certain groups.

  In addition to these critiques, some commenters express interest in further research on the topic. They suggest exploring the potential reversibility of these epigenetic changes and the long-term health consequences for future generations. Some also call for more research into the epigenetic effects of other types of trauma and adversity. Despite the expressed interest, the dominant tone of the comments is one of cautious skepticism about the study's conclusions and methodology.