Scientists have characterized the way age and metabolism can present in the microbiome.
Researchers in China developed an age-related and metabolism-related microbial signature based on findings from investigations in a cohort of over 10,000 Chinese people, and verified it on a cohort of over 9,000 Chinese people.
They then looked at the impacts these signatures had on cardiovascular disease risk. The researchers published their results in Nature Medicine. The gut microbiome is the population of bacteria, viruses and other microbes, playing a role in digestion, but also in other processes, including nerve signaling, immune response and hormones.
What metabolic parameters are linked to aging?
First, the researchers looked at a cohort of 10,207 Chinese participants, collecting information on 21 metabolic parameters to classify individuals into five “metabolic multimorbidity clusters” clusters. These were:
- MC1: healthy
- MC2: low high-density lipoprotein (HDL) cholesterol
- MC3: high low-density lipoprotein (LDL) cholesterol
- MC4: obesity-related mixed
- MC5: hyperglycemia (high blood sugar)
They then looked at the impact of being in one of these clusters on overall cardiovascular disease risk over an average follow-up of 11.1 years.
They discovered that people in the obesity and hyperglycemia clusters were 75% and 117%, respectively, more likely to develop cardiovascular disease when compared to the healthy cluster.
The MC1, MC2, and MC3 clusters were all linked to “healthy” parameters, while MC4 and MC5 were associated with “unhealthy” parameters. These results were then validated in a cohort of 9,061 individuals, with a 10-year follow-up.
Certain bacteria may influence aging
Researchers then looked at the gut microbiome of 4,491 participants from the original cohort, and sequenced the genomes of the microbes found there, to identify the presence and abundance of particular species.
They discovered that the microbiomes of people they assigned to the metabolic multimorbidity clusters had certain overlapping characteristics.
They also characterized the species that were found in the microbiome of younger people and older people. They then plotted the presence of 55 age-related microbial species against age to develop a gut microbial age metric, which they then validated using existing cross-sectional data from Israel, the Netherlands, France, Germany and the United Kingdom and United States.
The microbiomes of younger people were associated with lower levels of Bacteroides species and older people had higher levels of Prevotella and Enterobacteriaceae species.
Can we harness the microbiome to prevent heart disease?
The study authors also pointed at microbial variation between individuals in different countries, and stated this could be an area for further research.
Further analysis showed that a younger microbial age was associated with lower cardiovascular disease risk.
The authors have argued this could mean the microbiome could be a target for cardiovascular disease prevention in older adults who are not metabolically healthy.
“While there is some merit to the idea that microbiome health can correlate effectively with someone’s biological age, our gut microbiomes are also highly changeable through prebiotic and probiotic supplementation and potentially even more extreme measures like fecal transplantation,“ she noted.
“I wouldn’t say that this represents our ability to reverse aging, but it can definitely help to improve health outcomes in people as they age,” said Rall.
The findings of this research are backed up by evidence from other studies, which have shown that gut dysbiosis — imbalance of bacterial populations in the gut — is associated with a range of inflammatory conditions, including inflammatory bowel disease (IBD), rheumatoid arthritis, and systemic lupus erythematous, but also cardiovascular disease.
There are also links between those conditions, including IBD, and cardiovascular disease.
The authors of this study looked at heart attack, stroke, and death related to cardiovascular events, but other studies have linked gut dysbiosis to a range of cardiovascular risk factors, including atherosclerosis, hypertension, heart failure, chronic kidney diseaseTrusted Source, obesityTrusted Source, and type 2 diabetes.
By Hannah Flynn
Source: MedicalNewsToday
