Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
Review
. 2022 Jul 8;63(8):21.
doi: 10.1167/iovs.63.8.21.

Evidence Suggesting the Role of Gut Dysbiosis in Diabetic Retinopathy

Affiliations
Review

Evidence Suggesting the Role of Gut Dysbiosis in Diabetic Retinopathy

Pratima Singh Thakur et al. Invest Ophthalmol Vis Sci. .

Abstract

Purpose: Gut dysbiosis has been identified and tested in human trials for its role in diabetes mellitus (DM). The gut-retina axis could be a potential target for retardation of diabetic retinopathy (DR), a known complication of DM. This study reviews the evidence suggesting gut dysbiosis in DR.

Methods: The published literature in the past 5 years was reviewed using predetermined keywords and articles. The review intended to determine changes in gut microbiome in DR, the hypothesized mechanisms linking to the gut-retina axis, its predictive potential for progression of DR, and the possible therapeutic targets.

Results: The gut microbiota of people with DM differ from those without it, and the gut microbiota of people with DR differ from those without it. The difference is more significant in the former (DM versus no DM) and less significant in the latter (DM without DR versus DM with DR). Early research has suggested mechanisms of the gut-retina axis, but these are not different from known changes in the gut microbiome of people with DM. The current evidence on the predictive value of the gut microbiome in the occurrence and progression of DR is low. Therapeutic avenues targeting the gut-retina axis include lifestyle changes, pharmacologic inhibitors, probiotics, and fecal microbiota transplantation.

Conclusions: Investigating the therapeutic utility of the gut ecosystem for DM and its complications like DR is an emerging area of research. The gut-retina axis could be a target for retardation of DR but needs longitudinal regional studies adjusting for dietary habits.

PubMed Disclaimer

Conflict of interest statement

Disclosure: P.S. Thakur, None; D. Aggarwal, None; B. Takkar, None; S. Shivaji, None; T. Das, None

Figures

Figure 1.
Figure 1.
Venn diagrams depicting differences in abundance of gut microbiome at genera levels in DM and DR in comparison to healthy human controls. (A) Reduced abundance. (B) Increased abundance. The highlighted organisms indicate differences in findings of studies, where one study showed increased while the other showed decreased. Citation (1) refers to a study by Das et al. and (2) refers to a study by Huang et al.
Figure 2.
Figure 2.
The links between gut–retina axis and its components in DR. The image describes the various possible mechanisms linking the gut to retina in DR, as well as the components of each hypothetical gut–retina axis. The six axes revolve around LPS and leaky gut barrier, short-chain fatty acid production, modulation of VEGF, gut inflammatory changes, TUDCA, and ACE2 deficiency.

References

    1. International Diabetes Federation. IDF Diabetes Atlas, 10th edn. Brussels, Belgium: International Diabetes Federation, 2021, https://www.bionity.com/en/associations/61015/international-diabetes-fed.... Accessed October 29, 2021.
    1. Tilahun M, Gobena T, Dereje D, Welde M, Yideg G.. Prevalence of diabetic retinopathy and its associated factors among diabetic patients at Debre Markos Referral Hospital, northwest Ethiopia, 2019: hospital-based cross-sectional study. Diabetes Metab Syndr Obes Targets Ther. 2020; 13: 2179–2187. - PMC - PubMed
    1. GBD 2019 Diseases and Injuries Collaborators. Global burden of 369 diseases and injuries in 204 countries and territories, 1990-2019: a systematic analysis for the Global Burden of Disease Study 2019. Lancet. 2020; 396(10258): 1204–1222. - PMC - PubMed
    1. Steinmetz JD, Bourne RRA, Briant PS, et al. .. Causes of blindness and vision impairment in 2020 and trends over 30 years, and prevalence of avoidable blindness in relation to VISION 2020: the Right to Sight: an analysis for the Global Burden of Disease Study. Lancet Glob Health. 2021; 9(2): e144–e160. - PMC - PubMed
    1. Porta M, Bandello F.. Diabetic retinopathy. Diabetologia. 2002; 45(12): 1617–1634. - PubMed

Publication types