Lakshmi Lavanya Reddy

BACKGROUND: Circulating microRNAs (miRNA) are present in body fluids in stable, cell-free form. Likewise, these miRNAs can be identified in various stages of coronary artery disease (CAD) such as inflammation, endothelial dysfunction, proliferation and atherosclerosis among others. miRNA expression levels can be identified. AIMS AND OBJECTIVES: To determine the expression of circulating miRNAs (miR-126, miR-92, miR-33, miR-145 and miR-155) in CAD patients of Indian origin. MATERIAL AND METHODS: miRNA profiling analysis in blood plasma was performed by quantitative real-time-PCR (qRT-PCR) in 60 angiographically verified subjects including 30 CAD patients and 30 age- and gender-matched controls. Association between the expression of all five circulating miRNAs and clinical characteristics of patients with CAD were analysed using Medcalc statistics. The severity of CAD was assessed using SYNTAX score (SS). RESULTS: Expression of plasma miR-33 increased by 2.9 folds in CAD patients than in control group (p value ≥0.002) also it was found that miR-33 expression levels in mild cases (SS: ≤22) were significantly higher than CAD controls. There was a modest negative correlation between miR-33 and total cholesterol/high density lipoprotein ratio, triglycerides and very low density lipoprotein. CONCLUSION: The study reports a significant association between increased levels of plasma miR-33 and CAD. Thus, plasma miR-33 appears to be a promising non-invasive biomarker, but requires further validation in a large cohort.

Familial hypercholesterolemia (FH) is a common autosomal dominant disorder that affects ∼1 in 250-500 individuals globally. The only prevalence study in India shows FH in 15% of patients with premature CAD in North Indians. There are only 6 genetic studies in India of the total mutations, 32% are LDLR mutations, 4% are ApoB, 2% are PCSK9 mutations and the mutational spectrum for 37% is unknown. This calls for widespread genetic screening which could help identify definite FH patients. European Atherosclerosis Society-Familial Hypercholesterolemia Studies Collaboration (EAS- FHSC) has taken an initiative to develop a worldwide registry of FH. India is also a part of the collaboration and 3 groups from Mumbai, Delhi and Chennai are actively contributing to this registry. We believe this review might help to understand the Indian scenario of FH and investigators across India can contribute in managing FH in India and further help in the detection, diagnosis and treatment.