Intestinal microbiome research and metabolite analysis cannot be ignored!

To better understand the potential impact of gut microbes on human health, clinicians need to know not just the bacteria present in stool samples, but also the metabolites such as amino acids produced by those bacteria, say Australian and British researchers. The findings were published this week in the journal mSphere.

 

 

 

Dr Geraint B. Rogers, associate professor of microbiology and infectious diseases and member of the South Australian Institute of Health and Medical Research, said: "Typical DNA-based studies of the human microbiome or bacterial composition are limited because they do not reflect the metabolism of microbial colonies. Products. Studying the microbiome and its metabolites (metabolome) should be complementary, but because many microorganisms play the same role and some utilize the metabolites of other microorganisms, predicting metabolites is very challenging." The MetID team of Medicilon is composed of experienced scientists. We provide fast and reliable in vivo and in vitro MetID and reactive metabolite capture services. We also support new drug screening and domestic and oversees IND filings. Since the establishment of MetID team, Medicilon has successfully completed multiple different types of research projects for clients, including challenging peptide MetID research.

 

 

 

Rogers points out: Characterizing the metabolites of the gut microbiota, which can modulate the function of the human immune system and central nervous system, is critical to understanding how they affect human health. Therefore, analyzing the changes in intestinal microbiota and their corresponding metabolites caused by antibiotic drugs can provide insights into the acute and chronic effects of antibiotic drugs and provide a better understanding of the relationship between intestinal microbial metabolites and body health. connect.

 

 

 

Rogers and James Mason, a senior lecturer in membrane biochemistry at College London, used a combination of next-generation sequencing and nuclear magnetic resonance (NMR) techniques to treat mice with the antibiotics ciprofloxacin or vancomycin imipenem. of the microbiome and metabolites. They took fecal samples from the mice before antibiotic treatment, 14 days after treatment, and 9 days after stopping antibiotic treatment. One group of mice was not given any antibiotics and served as a blank control.

 

 

 

Ciprofloxacin treatment resulted in a significant reduction in microbial taxa abundance (the number of different types of bacteria in a sample) but had no effect on microbiota diversity or evenness. In contrast, vancomycin and imipenem treatment resulted in significant reductions in taxa abundance, evenness, and diversity.

 

 

 

The researchers pointed out that within 14 days of antibiotic treatment, antibiotic treatment led to significant changes in the composition and structure of the microbial flora. Ciprofloxacin caused significant or even decreases in the numbers of several types of bacteria, including Streptococcus, Lactobacillus, and Clostridium, while increasing numbers of Bacteroidetes and other species. Some genera were even completely depleted. Vancomycin and imipenem treatment also caused significant changes, including a decrease in Bacteroidetes and Firmicutes members and an increase in the relative abundance of Proteobacteria.

 

 

 

"However, many bacterial populations are altered by antibiotic treatment in ways that contribute to human health," Rogers said. "For example, the reduced Ruminococcaceae family produces important short-chain fatty acids by fermenting carbohydrates that humans cannot absorb. These fatty acids contribute to our health in many ways, including epithelial cell renewal, reduced colon cancer risk; intestinal barrier function, protection against bacteria enter the bloodstream; and modulate immune and metabolic control. Antibiotic drugs also increase levels of bacteria of the genus Enterobacter, several of which are capable of causing disease."

 

 

 

The team also investigated the extent to which fecal microbial colonies recovered nine days after antibiotic treatment was discontinued. In the ciprofloxacin group, microbial taxa abundance levels remained constant over this time, but microbiota uniformity and diversity were significantly reduced compared to levels measured before and at the end of treatment. In the vancomycin-imipenem group, the levels of microbial taxa abundance, evenness, and diversity increased significantly 9 days after discontinuation of antibiotic drug treatment compared with the levels measured at the end of treatment, but did not reach the level of antibiotic drugs. The level seen before processing begins. Compared with the control group, the microbial flora composition in the vancomycin-imipenem group was more different than that in the ciprofloxacin group, indicating that the recovery of the microbial flora in the vancomycin-imipenem-treated group was slower.

 

 

 

The researchers observed significant changes in intestinal microbial metabolites in mice before and after antibiotic drug treatment. Mice treated with ciprofloxacin had significantly increased levels of amino acids, such as valine, leucine, and phenylalanine, and decreased levels of sugars compared with controls. Increases in these types of amino acids are associated with an increased risk of type 2 diabetes and the development of metabolic diseases. Mice treated with vancomycin imipenem had greater before-to-post differences, including lower levels of amino acids such as alanine, methionine, tyrosine, the organic acid citrate, and propionate. The researchers also observed increased levels of sucrose, sarcosine and other compounds.

 

 

 

In a follow-up study, Rogers and colleagues evaluated whether similar effects could be observed in humans with prebiotics (dietary supplements that promote the growth of beneficial microorganisms in the gut) or fecal microbiota transplants (reprogramming of a person's gut microbiome). introduced) could be used as treatments to limit these effects.