Perspective

Bacterium leads to better metabolic health in adults with obesity

The gut microbe Akkermansia muciniphila, a mucin-degrading bacterium, was associated with improved metabolic health and clinical outcomes after calorie restriction in individuals with overweight and obesity, according to recent study data.

A. muciniphila has been previously shown to lower body fat mass, improve glucose homoeostasis, decrease adipose tissue inflammation and increase gut integrity in mice, but the role of this gut microbe in humans “remains ambiguous.” Researchers from Europe, therefore, assessed potential associations between fecal A. muciniphila abundance, fecal microbial gene richness, diet, host anthropometric and metabolic characteristics and their subsequent changes after a calorie restriction intervention in adults with overweight and obesity (n = 49; 41 women).

Participants did not have diabetes or chronic or inflammatory diseases, did not take antibiotics for 2 months before stool collection, and adhered to a 6-week calorie restriction diet followed by a 6-week weight stabilization period.

Researchers found that A. muciniphila had an inverse association with fasting glucose, waist-to-hip ratio and subcutaneous adipocyte diameter at baseline. Higher abundance of A. muciniphila along with greater microbial gene richness was associated with healthier metabolic status, especially in fasting plasma glucose, plasma triglycerides and body fat distribution. Higher baseline A. muciniphila was associated with greater improvement in insulin sensitivity markers and other clinical parameters after the calorie restriction intervention. Calorie restriction was linked to a reduction in A. muciniphila abundance overall, but the abundance remained more than 100 times higher in individuals with higher baseline abundance compared with those who had lower baseline abundance. A. muciniphila was also associated with 27 other metagenomic species (P < .01) that may be part of “an ecosystem that influences the complicated interaction between host biology and environment,” according to researchers. – by Adam Leitenberger

Disclosure: The researchers report no relevant financial disclosures.

The gut microbe Akkermansia muciniphila, a mucin-degrading bacterium, was associated with improved metabolic health and clinical outcomes after calorie restriction in individuals with overweight and obesity, according to recent study data.

A. muciniphila has been previously shown to lower body fat mass, improve glucose homoeostasis, decrease adipose tissue inflammation and increase gut integrity in mice, but the role of this gut microbe in humans “remains ambiguous.” Researchers from Europe, therefore, assessed potential associations between fecal A. muciniphila abundance, fecal microbial gene richness, diet, host anthropometric and metabolic characteristics and their subsequent changes after a calorie restriction intervention in adults with overweight and obesity (n = 49; 41 women).

Participants did not have diabetes or chronic or inflammatory diseases, did not take antibiotics for 2 months before stool collection, and adhered to a 6-week calorie restriction diet followed by a 6-week weight stabilization period.

Researchers found that A. muciniphila had an inverse association with fasting glucose, waist-to-hip ratio and subcutaneous adipocyte diameter at baseline. Higher abundance of A. muciniphila along with greater microbial gene richness was associated with healthier metabolic status, especially in fasting plasma glucose, plasma triglycerides and body fat distribution. Higher baseline A. muciniphila was associated with greater improvement in insulin sensitivity markers and other clinical parameters after the calorie restriction intervention. Calorie restriction was linked to a reduction in A. muciniphila abundance overall, but the abundance remained more than 100 times higher in individuals with higher baseline abundance compared with those who had lower baseline abundance. A. muciniphila was also associated with 27 other metagenomic species (P < .01) that may be part of “an ecosystem that influences the complicated interaction between host biology and environment,” according to researchers. – by Adam Leitenberger

Disclosure: The researchers report no relevant financial disclosures.

    Perspective
    Suzanne Devkota, PhD

    Suzanne Devkota

    The recent study by Dao and colleagues offers much needed human data to the wealth of rodent microbiome data that currently exist. Understanding the role of the intestinal microbiota on metabolic health and disease is a high priority in the microbiome field, and studies such as this can begin to lend insight into this intricate relationship.

    Increased growth in the bacterium Akkermansia muciniphila has been associated in several previous mouse and human studies with improved metabolic outcomes and appears to increase with metformin treatment as well. However, the exact mechanism behind these associations is still unknown. In contrast, the current study shows an overall decrease in A. muciniphila with a beneficial therapy caloric restriction but interestingly, those individuals who exhibited metabolic improvements in response to the treatment also had higher levels of A. muciniphila than those who did not. This adds further evidence that this bacterium may be conferring some metabolic benefit to the host. As the authors point out, this is an association study. In order to truly translate these interesting observations into potentially targetable therapies, we need to better understand the metabolism of bacteria and the host together as a functioning unit and the mechanisms driving the system.

    • Suzanne Devkota, PhD
    • Joslin Diabetes Center, Boston

    Disclosures: Disclosure: Devkota reports no relevant financial disclosures.