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Archive for the ‘Gut Microbiome and Obesity’ Category


Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

Obesity is a global concern that is associated with many chronic complications such as type 2 diabetes, insulin resistance (IR), cardiovascular diseases, and cancer. Growing evidence has implicated the digestive system, including its microbiota, gut-derived incretin hormones, and gut-associated lymphoid tissue in obesity and IR. During high fat diet (HFD) feeding and obesity, a significant shift occurs in the microbial populations within the gut, known as dysbiosis, which interacts with the intestinal immune system. Similar to other metabolic organs, including visceral adipose tissue (VAT) and liver, altered immune homeostasis has also been observed in the small and large intestines during obesity.

 

A link between the gut microbiota and the intestinal immune system is the immune-derived molecule immunoglobulin A (IgA). IgA is a B cell antibody primarily produced in dimeric form by plasma cells residing in the gut lamina propria (LP). Given the importance of IgA on intestinal–gut microbe immunoregulation, which is directly influenced by dietary changes, scientists hypothesized that IgA may be a key player in the pathogenesis of obesity and IR. Here, in this study it was demonstrate that IgA levels are reduced during obesity and the loss of IgA in mice worsens IR and increases intestinal permeability, microbiota encroachment, and downstream inflammation in metabolic tissues, including inside the VAT.

 

IgA deficiency alters the obese gut microbiota and its metabolic phenotype can be recapitulated into microbiota-depleted mice upon fecal matter transplantation. In addition, the researchers also demonstrated that commonly used therapies for diabetes such as metformin and bariatric surgery can alter cellular and stool IgA levels, respectively. These findings suggested a critical function for IgA in regulating metabolic disease and support the emerging role for intestinal immunity as an important modulator of systemic glucose metabolism.

 

Overall, the researchers demonstrated a critical role for IgA in regulating intestinal homeostasis, metabolic inflammation, and obesity-related IR. These findings identify intestinal IgA+ immune cells as mucosal mediators of whole-body glucose regulation in diet-induced metabolic disease. This research further emphasized the importance of the intestinal adaptive immune system and its interactions with the gut microbiota and innate immune system within the larger network of organs involved in the manifestation of metabolic disease.

 

Future investigation is required to determine the impact of IgA deficiency during obesity in humans and the role of metabolic disease in human populations with selective IgA deficiency, especially since human IgA deficiency is associated with an altered gut microbiota that cannot be fully compensated with IgM. However, the research identified IgA as a critical immunological molecule in the intestine that impacts systemic glucose homeostasis, and treatments targeting IgA-producing immune populations and SIgA may have therapeutic potential for metabolic disease.

 

References:

 

https://www.nature.com/articles/s41467-019-11370-y?elqTrackId=dc86e0c60f574542b033227afd0fdc8e

 

https://www.jci.org/articles/view/88879

 

https://www.nature.com/articles/nm.2353

 

https://diabetes.diabetesjournals.org/content/57/6/1470

 

https://www.sciencedirect.com/science/article/pii/S1550413115001047?via%3Dihub

 

https://www.sciencedirect.com/science/article/pii/S1550413115002326?via%3Dihub

 

https://www.sciencedirect.com/science/article/pii/S1931312814004636?via%3Dihub

 

https://www.nature.com/articles/nature15766

 

https://www.sciencedirect.com/science/article/pii/S1550413116000371?via%3Dihub

 

https://www.nature.com/articles/nm.2001

 

https://www.sciencedirect.com/science/article/abs/pii/S1550413118305047?via%3Dihub

 

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Celiac Disease Breakthrough: (1) 472 genes regulated differently in organoids reflecting celiac disease than in non-celiac control organoids (2) bio-products derived from gut microorganisms can be employed to modify the epithelial response to gluten, a finding that could lead to future treatment strategies.

 

Reporter: Aviva Lev-Ari, PhD, RN

“These results confirm our hypothesis that genes and exposure to gluten are necessary but not sufficient, since changes in both the composition and function of the gut microbiome are also needed to switch from genetic predisposition to clinical outcome, as shown by our data,” said Alessio Fasano, HMS professor of pediatrics at Mass General, director of MIBRC and co-senior author of the paper.

https://hms.harvard.edu/news/major-shift?utm_source=Silverpop&utm_medium=email&utm_term=field_news_item_3&utm_content=HMNews05132019

 

 

Image Source: iStock/wildpixel

Article OPEN Published: 

Human gut derived-organoids provide model to study gluten response and effects of microbiota-derived molecules in celiac disease

Scientific Reports volume 9, Article number: 7029 (2019Download Citation

Abstract

Celiac disease (CD) is an immune-mediated disorder triggered by gluten exposure. The contribution of the adaptive immune response to CD pathogenesis has been extensively studied, but the absence of valid experimental models has hampered our understanding of the early steps leading to loss of gluten tolerance. Using intestinal organoids developed from duodenal biopsies from both non-celiac (NC) and celiac (CD) patients, we explored the contribution of gut epithelium to CD pathogenesis and the role of microbiota-derived molecules in modulating the epithelium’s response to gluten. When compared to NC, RNA sequencing of CD organoids revealed significantly altered expression of genes associated with gut barrier, innate immune response, and stem cell functions. Monolayers derived from CD organoids exposed to gliadin showed increased intestinal permeability and enhanced secretion of pro-inflammatory cytokines compared to NC controls. Microbiota-derived bioproducts butyrate, lactate, and polysaccharide A improved barrier function and reduced gliadin-induced cytokine secretion. We concluded that: (1) patient-derived organoids faithfully express established and newly identified molecular signatures characteristic of CD. (2) microbiota-derived bioproducts can be used to modulate the epithelial response to gluten. Finally, we validated the use of patient-derived organoids monolayers as a novel tool for the study of CD.

Mass. General researchers develop 3D “mini-gut” model to study autoimmune response to gluten in celiac and non-celiac patient tissue

Gene expression of intestinal organoids reflects functional differences found in celiac disease

In pursuit of a novel tool for the research and treatment of celiac disease, scientists at the Mucosal Immunology and Biology Research Center (MIBRC) at Massachusetts General Hospital (MGH) have validated the use of intestinal organoids. These three-dimensional tissue cultures are miniature, simplified versions of the intestine produced in vitro. Taking tissue from duodenal biopsies of celiac and non-celiac patients, researchers created the “mini-guts” to explore how the gut epithelium and microbiota-derived molecules respond to gluten, a complex class of proteins found in wheat and other grains.

“We currently have no animal model that can recapitulate the response to gluten that we see in humans,” says Stefania Senger, PhD, co-senior author of the study published in Scientific Reports this week. “Using this human tissue model, we observed that intestinal organoids express the same molecular markers as actual epithelium in the celiac tissue, and the signature gene expression reflects the functional differences that occur when epithelia of celiac disease patients are exposed to gliadin.” Gliadin and glutenin proteins are main components of gluten.

Celiac disease is triggered when genetically predisposed individuals consume gluten. The condition affects approximately 1 percent of the U.S. population. Based on current data, the onset of celiac disease is thought to be preceded by the release of the protein zonulin, which is triggered by the activation of undigested gliadin to induce an autoimmune response. This leads to increased intestinal permeability and a disrupted barrier function. Novel evidence suggests that the microorganisms in the gastrointestinal tract may play a role in the onset of celiac disease.

Earlier studies from the MIBRC group and others have shown that human organoids “retain a gene expression that recapitulates the expression of the tissue of origin, including a diseased state,” the authors write. Through RNA sequencing, the new findings validate the organoid model as a “faithful in vitro model for celiac disease,” Senger says.
Using whole-transcriptome analysis, the researchers identified 472 genes regulated differently in organoids reflecting celiac disease than in non-celiac control organoids. These included novel genes associated with epithelial functions related to the pathogenesis of celiac disease – including gut barrier maintenance, stem cell regeneration and innate immune response. A second finding of the study shows that bioproducts derived from gut microorganisms can be employed to modify the epithelial response to gluten, a finding that could lead to future treatment strategies.

“These results confirm our hypothesis that genes and exposure to gluten are necessary but not sufficient, since changes in both the composition and function of the gut microbiome are also needed to switch from genetic predisposition to clinical outcome, as shown by our data,” says Alessio Fasano, MD, director of the Mucosal Immunology and Biology Research Center and co-senior author.

Senger adds, “We believe our observations represent a major shift in the study of celiac disease. We are confident that with adequate funding we could achieve major goals that include the development and implementation of high-throughput drug screenings to quickly identify new treatments for patients and expand the organoid repository to develop more complex models and pursue personalized treatment.”
Additional co-authors of the paper are first author Rachel Freire, PhD, along with Laura Ingano and Gloria Serena, PhD, of the MGH MIBRC; Murat Cetinbas, PhD, and Ruslan Sadreyev, PhD, MGH Department of Molecular Biology; Anthony Anselmo, PhD, formerly of MGH Molecular Biology and now with PatientsLikeMe, Cambridge, Mass.; and Anna Sapone, MD, PhD, Takeda Pharmaceuticals International. Support for the study includes National Institutes of Health grants RO1 DK104344-01A1 and 1U19 AI082655-02 and the Egan Family Foundation.

SOURCE

https://www.massgeneral.org/about/pressrelease.aspx?id=2403

 

Other related articles and e-Books by LPBI Group’s Authors published on this Open Access Online Scientific Journal include the following:

 

Series D: e-Books on BioMedicine – Metabolomics, Immunology, Infectious Diseases

  • Metabolomics 

VOLUME 1: Metabolic Genomics and Pharmaceutics. On Amazon.com since 7/21/2015

http://www.amazon.com/dp/B012BB0ZF0

Gluten-free Diets

Writer and Curator: Larry H. Bernstein, MD, FCAP

https://pharmaceuticalintelligence.com/2015/03/01/gluten-free-diets/

 

Breakthrough Digestive Disorders Research: Conditions affecting the Gastrointestinal Tract.

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2012/12/12/breakthrough-digestive-disorders-research-conditions-affecting-the-gastrointestinal-tract/

 

Collagen-binding Molecular Chaperone HSP47: Role in Intestinal Fibrosis – colonic epithelial cells and subepithelial myofibroblasts

Curators: Larry H Bernstein, MD, FCAP and Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2016/01/25/collagen-binding-molecular-chaperone-hsp47-role-in-intestinal-fibrosis-colonic-epithelial-cells-and-subepithelial-myofibroblasts/

Expanding area of Tolerance-inducing Autoimmune Disease Therapeutics: Key Players

Reporter: Aviva Lev-Ari, PhD, RN

https://pharmaceuticalintelligence.com/2017/01/17/expanding-area-of-tolerance-inducing-autoimmune-disease-therapeutics-key-players/

 

What is the key method to harness Inflammation to close the doors for many complex diseases?

Author and Curator: Larry H Bernstein, MD, FCAP

https://pharmaceuticalintelligence.com/2014/03/21/what-is-the-key-method-to-harness-inflammation-to-close-the-doors-for-many-complex-diseases/

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Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

The bacterial makeup of human milk is influenced by the mode of breastfeeding, according to a new study. Although previously considered sterile, breast milk is now known to contain a low abundance of bacteria. While the complexities of how maternal microbiota influence the infant microbiota are still unknown, this complex community of bacteria in breast milk may help to establish the infant gut microbiota. Disruptions in this process could alter the infant microbiota, causing predisposition to chronic diseases such as allergies, asthma, and obesity. While it’s unclear how the breast milk microbiome develops, there are two theories describing its origins. One theory speculates that it originates in the maternal mammary gland, while the other theory suggests that it is due to retrograde inoculation by the infant’s oral microbiome.

 

To address this gap in knowledge scientists carried out bacterial gene sequencing on milk samples from 393 healthy mothers three to four months after giving birth. They used this information to examine how the milk microbiota composition is affected by maternal factors, early life events, breastfeeding practices, and other milk components. Among the many factors analyzed, the mode of breastfeeding (with or without a pump) was the only consistent factor directly associated with the milk microbiota composition. Specifically, indirect breastfeeding was associated with a higher abundance of potential opportunistic pathogens, such as Stenotrophomonas and Pseudomonadaceae. By contrast, direct breastfeeding without a pump was associated with microbes typically found in the mouth, as well as higher overall bacterial richness and diversity. Taken together, the findings suggest that direct breastfeeding facilitates the acquisition of oral microbiota from infants, whereas indirect breastfeeding leads to enrichment with environmental (pump-associated) bacteria.

 

The researchers argued that this study supports the theory that the breast milk microbiome is due to retrograde inoculation. Their findings indicate that the act of pumping and contact with the infant oral microbiome influences the milk microbiome, though they noted more research is needed. In future studies, the researchers will further explore the composition and function of the milk microbiota. In addition to bacteria, they will profile fungi in the milk samples. They also plan to investigate how the milk microbiota influences both the gut microbiota of infants and infant development and health. Specifically, their projects will examine the association of milk microbiota with infant growth, asthma, and allergies. This work could have important implications for microbiota-based strategies for early-life prevention of chronic conditions.

 

References:

 

https://www.genomeweb.com/sequencing/human-breast-milk-microbiome-affected-mode-feeding#.XIOH0igzZPY

 

http://childstudy.ca/2019/02/13/breastmilk-microbiome-linked-to-method-of-feeding/

 

https://gizmodo.com/pumping-breast-milk-changes-its-microbiome-1832568169

 

https://www.sciencedaily.com/releases/2019/02/190213124445.htm

 

https://www.cell.com/cell-host-microbe/fulltext/S1931-3128(19)30049-6

 

https://www.unicef.org.uk/babyfriendly/news-and-research/baby-friendly-research/infant-health-research/epigenetics-microbiome-research/

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Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

The relationship between gut microbial metabolism and mental health is one of the most intriguing and controversial topics in microbiome research. Bidirectional microbiota–gut–brain communication has mostly been explored in animal models, with human research lagging behind. Large-scale metagenomics studies could facilitate the translational process, but their interpretation is hampered by a lack of dedicated reference databases and tools to study the microbial neuroactive potential.

 

Out of all the many ways, the teeming ecosystem of microbes in a person’s gut and other tissues might affect health. But, its potential influences on the brain may be the most provocative for research. Several studies in mice had indicated that gut microbes can affect behavior, and small scale studies on human beings suggested this microbial repertoire is altered in depression. Studies by two large European groups have found that several species of gut bacteria are missing in people with depression. The researchers can’t say whether the absence is a cause or an effect of the illness, but they showed that many gut bacteria could make substances that affect the nerve cell function—and maybe the mood.

 

Butyrate-producing Faecalibacterium and Coprococcus bacteria were consistently associated with higher quality of life indicators. Together with DialisterCoprococcus spp. was also depleted in depression, even after correcting for the confounding effects of antidepressants. Two kinds of microbes, Coprococcus and Dialister, were missing from the microbiomes of the depressed subjects, but not from those with a high quality of life. The researchers also found the depressed people had an increase in bacteria implicated in Crohn disease, suggesting inflammation may be at fault.

 

Looking for something that could link microbes to mood, researchers compiled a list of 56 substances important for proper functioning of nervous system that gut microbes either produce or break down. They found, for example, that Coprococcus seems to have a pathway related to dopamine, a key brain signal involved in depression, although they have no evidence how this might protect against depression. The same microbe also makes an anti-inflammatory substance called butyrate, and increased inflammation is implicated in depression.

 

Still, it is very much unclear that how microbial compounds made in the gut might influence the brain. One possible channel is the vagus nerve, which links the gut and brain. Resolving the microbiome-brain connection might lead to novel therapies. Some physicians and companies are already exploring typical probiotics, oral bacterial supplements, for depression, although they don’t normally include the missing gut microbes identified in the new study.

 

References:

 

https://www.sciencemag.org/news/2019/02/evidence-mounts-gut-bacteria-can-influence-mood-prevent-depression?utm_source=Nature+Briefing

 

https://www.nature.com/articles/s41564-018-0337-x

 

https://www.ncbi.nlm.nih.gov/pubmed/22968153

 

https://www.ncbi.nlm.nih.gov/pubmed/24888394

 

https://www.ncbi.nlm.nih.gov/pubmed/27067014

 

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Benefits of Fiber in Diet

Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

UPDATED on 1/15/2019

This is How Much Daily Fiber to Eat for Better Health – More appears better in meta-analysis — as in more than 30 g/day

by Ashley Lyles, Staff Writer, MedPage Today

In the systematic review, observational data showed a 15% to 30% decline in cardiovascular-related death, all-cause mortality, and incidence of stroke, coronary heart disease, type 2 diabetes, and colorectal cancer among people who consumed the most dietary fiber compared to those consuming the lowest amounts.

Whole grain intake yielded similar findings.

Risk reduction associated with a range of critical outcomes was greatest when daily intake of dietary fibre was between 25 g and 29 g. Dose-response curves suggested that higher intakes of dietary fibre could confer even greater benefit to protect against cardiovascular diseases, type 2 diabetes, and colorectal and breast cancer.

https://www.thelancet.com/pdfs/journals/lancet/PIIS0140-6736(18)31809-9.pdf

Eating more dietary fiber was linked with lower risk of disease and death, a meta-analysis showed.

According to observational studies, risk was reduced most for a range of critical outcomes from all-cause mortality to stroke when daily fiber consumption was between 25 grams and 29 grams, reported Jim Mann, PhD, of University of Otago in Dunedin, New Zealand, and colleagues in The Lancet.

By upping daily intake to 30 grams or more, people had even greater prevention of certain conditions: colorectal and breast cancer, type 2 diabetes, and cardiovascular diseases, according to dose-response curves the authors created.

Quantitative guidelines relating to dietary fiber have not been available, the researchers said. With the GRADE method, they determined that there was moderate and low-to-moderate certainty of evidence for the benefits of dietary fiber consumption and whole grain consumption, respectively.

Included in the systematic review were 58 clinical trials and 185 prospective studies for a total of 4,635 adult participants with 135 million person-years of information (one trial in children was included, but analyzed separately from adults). Trials and prospective studies assessing weight loss, supplement use, and participants with a chronic disease were excluded.

 

Food is digested by bathing in enzymes that break down its molecules. Those molecular fragments then pass through the gut wall and are absorbed in our intestines. But our bodies make a limited range of enzymes, so that we cannot break down many of the tough compounds in plants. The term “dietary fiber” refers to those indigestible molecules. These dietary fibers are indigestible only to us. The gut is coated with a layer of mucus, on which sits a carpet of hundreds of species of bacteria, part of the human microbiome. Some of these microbes carry the enzymes needed to break down various kinds of dietary fibers.

 

Scientists at the University of Gothenburg in Sweden are running experiments that are yielding some important new clues about fiber’s role in human health. Their research indicates that fiber doesn’t deliver many of its benefits directly to our bodies. Instead, the fiber we eat feeds billions of bacteria in our guts. Keeping them happy means our intestines and immune systems remain in good working order. The scientists have recently reported that the microbes are involved in the benefits obtained from the fruits-and-vegetables diet. Research proved that low fiber diet decreases the gut bacteria population by tenfold.

 

Along with changes to the microbiome there were also rapid changes observed in the experimental mice. Their intestines got smaller, and its mucus layer thinner. As a result, bacteria wound up much closer to the intestinal wall, and that encroachment triggered an immune reaction. After a few days on the low-fiber diet, mouse intestines developed chronic inflammation. After a few weeks, they started putting on fat and developing higher blood sugar levels. Inflammation can help fight infections, but if it becomes chronic, it can harm our bodies. Among other things, chronic inflammation may interfere with how the body uses the calories in food, storing more of it as fat rather than burning it for energy.

 

In a way fiber benefits human health is by giving, indirectly, another source of food. When bacteria finished harvesting the energy in the dietary fiber, they cast off the fragments as waste. That waste — in the form of short-chain fatty acids — is absorbed by intestinal cells, which use it as fuel. But the gut’s microbes do more than just make energy. They also send messages. Intestinal cells rely on chemical signals from the bacteria to work properly. The cells respond to the signals by multiplying and making a healthy supply of mucus. They also release bacteria-killing molecules. By generating these responses, gut bacteria help to maintain a peaceful coexistence with the immune system. They rest on the gut’s mucus layer at a safe distance from the intestinal wall. Any bacteria that wind up too close get wiped out by antimicrobial poisons.

 

A diet of fiber-rich foods, such as fruits and vegetables, reduces the risk of developing diabetes, heart disease and arthritis. Eating more fiber seems to lower people’s mortality rate, whatever be the cause. Researchers hope that they will learn more about how fiber influences the microbiome to use it as a way to treat disorders. Lowering inflammation with fiber may also help in the treatment of immune disorders such as inflammatory bowel disease. Fiber may also help reverse obesity. They found that fiber supplements helped obese people to lose weight. It’s possible that each type of fiber feeds a particular set of bacteria, which send their own important signals to our bodies.

 

References:

 

https://www.nytimes.com/2018/01/01/science/food-fiber-microbiome-inflammation.html

 

 

https://www.ncbi.nlm.nih.gov/pubmed/29276171

 

https://www.ncbi.nlm.nih.gov/pubmed/29276170

 

https://www.ncbi.nlm.nih.gov/pubmed/29486139

 

https://www.mayoclinic.org/healthy-lifestyle/nutrition-and-healthy-eating/in-depth/fiber/art-20043983

 

https://nutritiouslife.com/eat-empowered/high-fiber-diet/

 

http://www.eatingwell.com/article/287742/10-amazing-health-benefits-of-eating-more-fiber/

 

http://www.cookinglight.com/eating-smart/nutrition-101/what-is-a-high-fiber-diet

 

https://www.helpguide.org/articles/healthy-eating/high-fiber-foods.htm

 

https://www.gicare.com/diets/high-fiber-diet/

 

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Reporter and Curator: Dr. Sudipta Saha, Ph.D.

 

The trillions of microbes in the human gut are known to aid the body in synthesizing key vitamins and other nutrients. But this new study suggests that things can sometimes be more adversarial.

 

Choline is a key nutrient in a range of metabolic processes, as well as the production of cell membranes. Researchers identified a strain of choline-metabolizing E. coli that, when transplanted into the guts of germ-free mice, consumed enough of the nutrient to create a choline deficiency in them, even when the animals consumed a choline-rich diet.

 

This new study indicate that choline-utilizing bacteria compete with the host for this nutrient, significantly impacting plasma and hepatic levels of methyl-donor metabolites and recapitulating biochemical signatures of choline deficiency. Mice harboring high levels of choline-consuming bacteria showed increased susceptibility to metabolic disease in the context of a high-fat diet.

 

DNA methylation is essential for normal development and has been linked to everything from aging to carcinogenesis. This study showed changes in DNA methylation across multiple tissues, not just in adult mice with a choline-consuming gut microbiota, but also in the pups of those animals while they developed in utero.

 

Bacterially induced reduction of methyl-donor availability influenced global DNA methylation patterns in both adult mice and their offspring and engendered behavioral alterations. This study reveal an underappreciated effect of bacterial choline metabolism on host metabolism, epigenetics, and behavior.

 

The choline-deficient mice with choline-consuming gut microbes also showed much higher rates of infanticide, and exhibited signs of anxiety, with some mice over-grooming themselves and their cage-mates, sometimes to the point of baldness.

 

Tests have also shown as many as 65 percent of healthy individuals carry genes that encode for the enzyme that metabolizes choline in their gut microbiomes. This work suggests that interpersonal differences in microbial metabolism should be considered when determining optimal nutrient intake requirements.

 

References:

 

https://news.harvard.edu/gazette/story/2017/11/harvard-research-suggests-microbial-menace/

 

http://www.cell.com/cell-host-microbe/fulltext/S1931-3128(17)30304-9

 

https://www.ncbi.nlm.nih.gov/pubmed/23151509

 

https://www.ncbi.nlm.nih.gov/pubmed/25677519

 

http://mbio.asm.org/content/6/2/e02481-14

 

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Functional Analysis of the Microbiome for Development of Potential Therapeutic Approaches to Weight Regain

Reporter: Aviva Lev-Ari, PhD, RN

 

Transplanting fecal microbes to prevent recurring obesity

Finally, the researchers used these insights to develop new treatments for recurrent obesity. They implanted formerly obese mice with gut microbes from mice that had never been obese. This fecal microbiome transplantation erased the “memory” of obesity in these mice when they were re-exposed to a high-calorie diet, preventing excessive recurrent obesity.

Gut Microbes Contribute to Recurrent ‘Yo-Yo’ Obesity, Study Shows

By Einat Paz-Frankel, NoCamels December 18, 2016

Researchers at Israel’s Weizmann Institute of Science have shown in mice that intestinal microbes – collectively termed the gut microbiome – play an unexpectedly important role in exacerbated post-dieting weight gain, and that this common phenomenon may in the future be prevented or treated by altering the composition or function of the microbiome.

“We’ve shown in obese mice that following successful dieting and weight loss, the microbiome retains a ‘memory’ of previous obesity,” Elinav said in a statement. “This persistent microbiome accelerated the regaining of weight when the mice were put back on a high-calorie diet or ate regular food in excessive amounts.”

http://nocamels.com/2016/12/gut-microbes-recurrent-obesity-diet/

 

Original Research

Persistent microbiome alterations modulate the rate of post-dieting weight regain

Nature (2016) doi:10.1038/nature20796

Corrected online

28 November 2016

Article tools

Abstract

In tackling the obesity pandemic, significant efforts are devoted to the development of effective weight reduction strategies, yet many dieting individuals fail to maintain a long-term weight reduction, and instead undergo excessive weight regain cycles. The mechanisms driving recurrent post-dieting obesity remain largely elusive. Here, we identify an intestinal microbiome signature that persists after successful dieting of obese mice, which contributes to faster weight regain and metabolic aberrations upon re-exposure to obesity-promoting conditions and transmits the accelerated weight regain phenotype upon inter-animal transfer. We develop a machine-learning algorithm that enables personalized microbiome-based prediction of the extent of post-dieting weight regain. Additionally, we find that the microbiome contributes to diminished post-dieting flavonoid levels and reduced energy expenditure, and demonstrate that flavonoid-based ‘post-biotic’ intervention ameliorates excessive secondary weight gain. Together, our data highlight a possible microbiome contribution to accelerated post-dieting weight regain, and suggest that microbiome-targeting approaches may help to diagnose and treat this common disorder.

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