Chichi Li1, Lechi Ye2, Li Yang3, Xiaofang Yu1, Yucang He1, Zhuojie Chen1, Liqun Li1, Dan Zhang3. 1. Department of Plastic Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China. 2. Department of Colorectal & Anal Surgery, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China. 3. Department of Respiratory Medicine, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China.
Abstract
BACKGROUND/AIMS: Ischemia is one of the main causes of the high rate of absorption of transplanted autologous fat. Autophagy allows cells to survive by providing energy under starvation. Rapamycin has been found to play a role in promoting autophagy. In this study, we investigated whether rapamycin participates in the survival and adipogenesis of ischemia-challenged adipose-derived stem cells (ADSCs) by regulating autophagy. METHODS: Before the cells were exposed to oxygen-glucose deprivation (OGD), a simulated ischemic microenvironment, the level of autophagy was reduced or increased by lentiviral transfection with short hairpin RNA targeting microtubule-associated protein 1-light chain 3 gene (shRNA-LC3) or treatment with rapamycin, respectively. The level of autophagy was assessed by western blotting, transmission electron microscopythen the apoptosis ratio was determined through terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and flow cytometry. Adipogenesis was further evaluated by oil red O staining and the expressions level of some specific proteins for adipocytes. RESULTS: shRNA-LC3 and rapamycin treatment effectively decreased and improved the level of autophagy in cells with or without OGD challenge, respectively. In addition, autophagy inhibition increased the apoptosis rate and activated caspase-3 expression level in response to OGD, and these were markedly inhibited by rapamycin preconditioning. During adipogenesis, autophagy inhibition decreased not only oil droplet accumulation but also lipoprotein lipase (LPL) and peroxisome proliferator-activated receptor gamma (PPARγ) expression in cells with or without OGD challenge. However, autophagy promotion by rapamycin increased oil droplet accumulation and LPL and PPARγ expression. CONCLUSIONS: Rapamycin may promote the survival and adipogenesis of ischemia-challenged ADSCs by upregulating autophagy.
BACKGROUND/AIMS: Ischemia is one of the main causes of the high rate of absorption of transplanted autologous fat. Autophagy allows cells to survive by providing energy under starvation. Rapamycin has been found to play a role in promoting autophagy. In this study, we investigated whether rapamycin participates in the survival and adipogenesis of ischemia-challenged adipose-derived stem cells (ADSCs) by regulating autophagy. METHODS: Before the cells were exposed to oxygen-glucose deprivation (OGD), a simulated ischemic microenvironment, the level of autophagy was reduced or increased by lentiviral transfection with short hairpin RNA targeting microtubule-associated protein 1-light chain 3 gene (shRNA-LC3) or treatment with rapamycin, respectively. The level of autophagy was assessed by western blotting, transmission electron microscopythen the apoptosis ratio was determined through terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) and flow cytometry. Adipogenesis was further evaluated by oil red O staining and the expressions level of some specific proteins for adipocytes. RESULTS: shRNA-LC3 and rapamycin treatment effectively decreased and improved the level of autophagy in cells with or without OGD challenge, respectively. In addition, autophagy inhibition increased the apoptosis rate and activated caspase-3 expression level in response to OGD, and these were markedly inhibited by rapamycin preconditioning. During adipogenesis, autophagy inhibition decreased not only oil droplet accumulation but also lipoprotein lipase (LPL) and peroxisome proliferator-activated receptor gamma (PPARγ) expression in cells with or without OGD challenge. However, autophagy promotion by rapamycin increased oil droplet accumulation and LPL and PPARγ expression. CONCLUSIONS:Rapamycin may promote the survival and adipogenesis of ischemia-challenged ADSCs by upregulating autophagy.
Authors: Rachel M Wise; Sara Al-Ghadban; Mark A A Harrison; Brianne N Sullivan; Emily R Monaco; Sarah J Aleman; Umberto M Donato; Bruce A Bunnell Journal: Cells Date: 2022-04-19 Impact factor: 7.666
Authors: Julia Bachmann; Elias Ehlert; Matthias Becker; Christoph Otto; Katrin Radeloff; Torsten Blunk; Petra Bauer-Kreisel Journal: Cells Date: 2020-08-21 Impact factor: 6.600
Authors: Rachel M Wise; Mark A A Harrison; Brianne N Sullivan; Sara Al-Ghadban; Sarah J Aleman; Amber T Vinluan; Emily R Monaco; Umberto M Donato; India A Pursell; Bruce A Bunnell Journal: Cells Date: 2020-09-30 Impact factor: 6.600