Alterations in the gut bacterial microbiome in people with type 2 diabetes mellitus and diabetic retinopathyOriginal paper
Karen Pendergrass is a microbiome researcher specializing in microbiome-targeted interventions (MBTIs). She systematically analyzes scientific literature to identify microbial patterns, develop hypotheses, and validate interventions. As the founder of the Microbiome Signatures Database, she bridges microbiome research with clinical practice. In 2012, based on her own investigative research, she became the first documented case of FMT for Celiac Disease, four years before the first published case study.
Read MoreWhat was studied?
This study examined whether gut bacterial microbiome dysbiosis, already reported in type 2 diabetes mellitus (T2DM), also links to diabetic retinopathy (DR). Fecal samples were analyzed using 16S rRNA gene sequencing, with community composition assessed using QIIME and R software. The researchers compared gut bacterial diversity and abundance at the phyla and genera level across groups.
Who was studied?
The study compared healthy controls (HC) with people who had T2DM without DR and people who had T2DM with DR. Exact sample sizes are not given in the abstract, but the design involved three human fecal-sample groups defined by diabetes and retinopathy status. This is described as the first report of its kind comparing gut microbiome dysbiosis specifically in people with DR against healthy controls.
What were the most important findings?
Gut microbiome dysbiosis at the phyla and genera level was observed in both T2DM and T2DM-with-DR groups compared to healthy controls. People with DR showed greater discrimination from healthy controls than people with T2DM alone, and the microbiomes of the T2DM and DR groups were also significantly different from each other. Both diabetes and DR were associated with a decrease in anti-inflammatory, probiotic, and other beneficial bacteria relative to healthy controls, alongside an increase in potentially pathogenic bacteria, with this shift being more pronounced in people with DR.
What are the greatest implications of this study?
This is the first report demonstrating gut microbiome dysbiosis specifically associated with diabetic retinopathy, distinct from T2DM alone. The findings suggest the gut microbiome could serve as a marker to distinguish DR from T2DM without retinal complications. The authors note this work could help inform the development of novel, targeted therapies aimed at improving treatment of diabetic retinopathy.