Fig. 2

MiR-377-3p regulates FAO of lipid metabolism through CPT1C. A Representative images of CY3-labeled palmitate (red) and staining of mitochondria (green) in HepG2 cells transfected with CPT1C expression plasmid or miR-377-3p mimics or miR-377-3p mimics plus CPT1C expression plasmid. The colocalization was shown as yellow. Graphs at the right panel show relative colocalization number of mitochondria and CPT1C. Results shown are mean ± SD of 3 independent experiments. Scale bar 10 μm. B FAO assay of HepG2 cells transfected as in A. Cells treated with FCCP were used as positive control, and cells treated with Eto were used as negative control. Eto, Etomoxir. Graphs at the right panel show relative FAO rate. Data shown are mean ± SD of 3 independent experiments. C HepG2 cells were transfected as in A and stained with BODIPY 493/503 and then the lipid droplet content was determined by flow cytometry. Graphs at the right panel show relative ratio of positive cells. Data shown are mean ± SD of three independent experiments. D Cells were transfected as in A and stained with Oil Red O. Graphs at the right panel show relative LD content. Data shown are mean ± SD of three independent experiments. Scale bar 20 μm. E Representative images of colocalization between green BODIPY 493/503 (lipid droplets) and red Mito Tracker (mitochondria). The colocalization was shown as yellow. Graphs at the right panel show relative colocalization of mitochondria and LD. Data shown are mean ± SD of three independent experiments. Scale bar 10 μm. F ATP production was determined in HepG2 and MHCC97H cells transfected as in A. Representative western blot confirms the expression of CPT1C. RT-qPCR analysis indicates miR-377-3p expression. Data are mean ± SD (n = 3). *p < 0.05 and **p < 0.01. G Correlation between miR-377-3p expression, CPT1C expression and lipid droplet level in 22 cell lines. The p value was generated using Spearman’s rank correlation test