Intestinal microbiota non-invasive indicators for diagnosing AMD clinically

China: In a study published in Frontiers in Microbiology, researchers have revealed alterations in intestinal microbiota compositions and metabolic functions between Age-related macular degeneration (AMD) patients and healthy individuals. The study has highlighted the perspective for targeting specific bacteria and potential microbial markers for managing AMD.

Previous research has revealed the association between intestinal microbiota and human disease resistance. Studies have acknowledged the role of intestinal microbiota in regulating eye diseases. Recent studies showed gut microbiota changes and potential applications in retinal disorders patients.

AMD is the leading cause of vision loss. Researchers have revealed that there is an association between gut microbiota and AMD. According to researchers, intestinal microbiota has a role in the pathogenesis of ocular diseases. Considering this background, the present study used 16S rRNA gene sequencing to identify differences in the gut microbiota of AMD patients and healthy individuals.

They collected Fecal samples of AMD (30 patients) and healthy controls and performed DNA extraction, PCR amplification, and 16S rRNA gene sequencing to identify intestinal microbial alterations. BugBase for phenotypic prediction and PICRUSt2 for KEGG Orthology (KO)and metabolic feature prediction were utilised by the researchers.

The study researchers could be summarised as follows:

• The intestinal microbiota was altered in the AMD group.
• There were lower levels of Firmicutes and relatively higher levels of Proteobacteria and Bacteroidota in the AMD group than in the control group.
• AMD patient group had a higher proportion of Escherichia-Shigella and lower proportions of Blautia and Anaerostipes than the control group at the genus level.
• PICRUSt2 analysis revealed KOs and pathways associated with the altered intestinal microbiota. Between the two groups, Phenotypic prediction showed differences in the four phenotypes.
• The abundance of the top eight KOs in the AMD group was higher than in the control group.
• The KOs had involvement in lipopolysaccharide biosynthesis.

They said, “We found that AMD patients had a different composition of gut microbiota than healthy controls. Moreover, we performed functional predictions of intestinal microbiota in patients with AMD.”

Based on the study's findings, AMD patients had different gut microbiota than healthy controls. The pathophysiology of AMD was tied to changes in gut-related metabolic pathways.

The study limitations include single-centre research, a small sample size, and more data on bacterial metabolites needed to determine their potential underlying mechanisms.

Further reading:

Zhang Y, Wang T, Wan Z, Bai J, Xue Y, Dai R, Wang M, Peng Q. Alterations of the intestinal microbiota in age-related macular degeneration. Front Microbiol. 2023 Apr 5;14:1069325. doi: 10.3389/fmicb.2023.1069325.