Elucidating miR-146a-3p as a key player in autophagy and lipid metabolism in Leishmania major infection

Autophagy is a key step involved in many unicellular eukaryotic diseases, including leishmaniasis, for cellular remodelling and differentiation during parasite's lifecycle. Lipids play a significant role in the infection process that begins with Leishmania major invading host cells. MicroRNAs (miRNAs), a family of small, 22–24 nucleotide noncoding regulatory RNAs, target mRNAs to modify gene expression and, subsequently, proteome output may have a regulatory role in altering the host cell processes. We observed miR-146a-3p expression increases in a time-dependent manner post Leishmania major infection. Transfecting miR-146a-3p mimic increases the expression of ATG7, an autophagy gene that encodes an E1-like enzyme in two ubiquitin-like conjugation systems required for autophagosome progression. HPGD (15-hydroxyprostaglandin dehydrogenase) operates as an enzyme, converting prostaglandin to its non-active form. Microarray data and western studies reveal that miR-146a-3p targets and inhibits HPGD, thereby increasing prostaglandin activity in lipid droplets. Herein, our research focuses on miR-146a-3p, which boosts ATG7 expression while reducing HPGD post Leishmania major infections helping us comprehend the intricate network of microRNA, autophagy, and lipid metabolism in leishmaniasis.