The miR-125a-3p is Associated With Leprosy Phenotypes and Correlated With Bacillary Index

Abstract Background. Mycobacterium leprae infects skin and peripheral nerves causing a broad of clinical forms. Data have shown that the miR-125a-3p can influence immune mechanisms such as autophagy as well as to target genes leading to abnormal proliferation, metastasis, and invasion of cells. Methods. Here we used quantitative real time PCR (qPCR) to evaluate the miR-125a-3p expression pattern as a marker for leprosy phenotypes in biopsies obtained from patients with and without reactions. Data were analysed according to clinical forms and bacillary index (BI). Results. Our results show a significant increase in the miR-125a-3p expression in paucibacillary (PB) vs multibacillary (MB) (p = 0.007) and vs RR (reversal reactions) (p = 0.005), respectively; and also a higher expression in patients with erythema nodosum leprosum (ENL) vs MB without reactions (p = 0.002). In addition, there was a positive correlation between the miR-125a-3p expression and BI in patients with reactions (r=0,81; p=0,002). Conclusions. All together we underpin a role for miR-125-3p in leprosy pathogenesis, raising the hypothesis that this miR might have a distinct role in PB and ENL forms, influencing mechanisms such as apoptosis and autophagy according to the local context. A functional study should help to validate the miR-125a-3p as a potential therapeutic target for leprosy treatment.