Vitamin D Deficiency Gut Microbiota Dysbiosis and Their Combined Impact on Insulin Resistance in Type 2 Diabetes Mellitus.

Abstract

Background: vitamin D Deficiency and changes in gut microbiota are progressively being accepted to play key roles in Type 2 Diabetes Mellitus (T2DM) pathogenesis. The two affect insulin sensitivity, systemic inflammation, and glucose metabolism, which play the key role in the development and evolution of the disease. Their interactions can be used to understand new preventive and treatment interventions.

Objectives: to establish the interaction between vitamin D deficiency, gut microbiota composition, and insulin resistance in T2DM patients and to determine the interplay between the two variables on glucose metabolism.

Methodology: A cross-sectional study was carried Conducted at Department of Medicine, LRH-MTI, Peshawar between jan 2019 and Dec 2019.100 patients with T2DM between the ages of 45 and 70 years. ELISA was used to measure serum vitamin D, 16S rRNA gene sequencing to measure gut microbiota composition, and the Homeostasis Model Assessment of Insulin Resistance (HOMA-IR) was used to measure insulin resistance. ANOVA and Pearson correlation statistical analysis were conducted to determine the relationship among levels of vitamin D, diversity of gut microbiota and insulin resistance, with a significant value of p<0.05.

Results: out of 100 patients 45 % of the participants were found to be deficient in vitamin D. The patients with deficiency had a much greater HOMA-IR value (mean 3.5 ± 1.3) than the patients with adequate levels of vitamin D (mean 2.1 ± 1.0, p<0.01). The microbiota population in the gut was significantly decreased in patients with vitamin D deficiency where there was a lower abundance of beneficial bacteria including Faecalibacterium prausnitzii. There were found significant correlations between low vitamin D, low microbiota diversity, and high insulin resistance (p<0.05).

Conclusion: Microbiota dysbiosis and Vitamin D deficiency are closely linked with augmented insulin delicacy in T2DM. Vitamin D-based intervention and microbiota-modulating interventions can enhance the glucose metabolism and offer an exciting solution to addressing T2DM.