microRNA-181a promotes the proliferation of hypertrophic scar fibroblasts and inhibits their apoptosis via targeting phosphatase and tensin homolog

Abstract

Background: This study aimed to compare the expression of microRNA (miR)-181a and phosphatase and tensin homolog (PTEN) in hypertrophic scar tissue and cells and to explore the effects of miR-181a and PTEN on the proliferation and apoptosis of the human scar fibroblast cell line HSFb.Methods: HSFb cells were transfected with miR-negative control (miR-NC), miR-181a mimics, miR-181a inhibitor, pcDNA3.1-PTEN (pc-PTEN), or small interfence-PTEN (si-PTEN) plasmid using a Lipofectamine 2000 transfection kit. The effects of miR-181a and PTEN on the proliferation and apoptosis of HSFb were determined using a Cell Counting Kit (CCK)-8 experiment and flow cytometry, respectively.The effects of miR-181a and PTEN on the expression of apoptosis-related proteins in HSFb, including type I collagen (Col-1) and type III collagen (Col-3), were measured by western blot. Finally, the relationship between miR-181a and PTEN was explored by the dual-luciferase reporter gene experiment. Results:The miR-181a in hypertrophic scar tissues and HSFb were significantly up-regulated compared to embryo skin fibroblast (ESF-1) cells and normal tissues (P<0.05), whereas the opposite results were seen for PTEN expression (P<0.05). Inhibiting miR-181a or upregulating the expression of PTEN significantly suppressed the proliferation of HSFb (P<0.05) and induced their apoptosis (P<0.05). Western blot revealed that inhibiting and upregulating miR-181a and PTEN, respectively, decreased the expression of the B-cell lymphoma-2 (Bcl-2), Col-1, and Col-3 proteins in HSFb, but significantly up-regulated the expression of Bcl-2-associated X protein (Bax), cleaved caspase-3 (c-caspase-3), and cleaved caspase-9 (c-caspase-9) (P<0.05). The dual-luciferase reporter gene experiment results confirmed PTEN to be the downstream target gene of miR-181a. Simultaneous upregulation of miR-181a and PTEN expression had no significant effect on the proliferation and apoptosis of HSFb.Conclusions: miR-181a promotes the up-regulation of Col-1 and Col-3, and regulates the proliferation and apoptosis of HSFb by targeting PTEN, thereby enhancing the formation of hypertrophic scarring (HS).Therefore, miR-181a and PTEN may be potential therapeutic targets for the treatment of HS.

Exosome Derived from Mesenchymal Stem Cells Alleviates Pathological Scars by Inhibiting the Proliferation, Migration and Protein Expression of Fibroblasts via Delivering miR-138-5p to Target SIRT1

“…Several recent developments in this area have involved the use of miRNAs. [16][17][18] However, there are difficulties in delivering miRNAs to cellular models. 19,20 Therefore, the use of exosomes provides an effective way for miRNAs delivery.…”