Gut microbiota as a key player in type 2 diabetes: Current perspectives

Type 2 diabetes mellitus (T2DM) is a pressing global health issue defined by impaired glucose metabolism, insulin resistance, and β-cell dysfunction. Emerging research underscores the involvement of the gut microbiome in the development and progression of T2DM. A comprehensive online search was conducted across PUBMED, SCOPUS, EMBASE, Web of Science, and Google Scholar to identify all original research articles published in India and internationally over the past 5 years on the topic of gut dysbiosis and diabetes. A mini review was carried out based on their findings. Composed of trillions of microorganisms, the gut microbiota influences host metabolism, immunity, and inflammatory responses. Dysbiosis, or imbalance in microbial composition—particularly, an altered Firmicutes/Bacteroidetes ratio—has been linked to metabolic disorders, including T2DM. Studies show that individuals with T2DM exhibit decreased levels of beneficial, fibre-degrading bacteria and increased opportunistic pathogens and mucus-degrading microbes. Antidiabetic drugs such as metformin, acarbose, glucagon-like peptide (GLP)-1 receptor agonists, and dipeptidyl peptidase-4 inhibitors have been shown to modulate the gut microbiome, suggesting a bidirectional relationship between microbiota and therapeutic efficacy. Furthermore, pharmacomicrobiomics—a field examining microbiota-drug interactions—highlights how individual microbial profiles may predict drug response and side effects. Specific bacteria, such as Enterococcus faecalis, can even degrade GLP-1, reducing the efficacy of GLP-1-based treatments. Incorporating prebiotics and probiotics into treatment regimens has shown potential in restoring microbial balance, increasing short-chain fatty acid production, and enhancing glucose metabolism. These interventions may support gut barrier integrity, reduce inflammation, and improve insulin sensitivity. This review seeks to examine the intricate connection between gut microbiome and T2DM, insights into the disease mechanisms, and opens avenues for personalized and more effective therapeutic strategies. Targeting the microbiome may revolutionize diabetes management by enabling microbiota-informed treatment approaches to mitigate disease burden.