1.Angiotensin (1-7) activates autophagy to regulates apoptosis and angiogenesis of oral submucosal fibroblasts
Lehong Qiu ; Wei Deng ; Chengwen Gan ; Ying Sun
Acta Universitatis Medicinalis Anhui 2023;58(3):457-464
Objective:
To observe the effect of angiotensin ( 1-7) [Ang( 1-7) ]on the apoptosis and angiogenesis of fibroblasts in the oral submucosal fibrosis ( OSF) ,and to explore the effect preliminarily mechanism.
Methods:
Fibroblasts were isolated and cultured from human buccal mucosal tissue,the cell morphology was observed by inverted microscope,and the expression of vimentin was detected by immunofluorescence staining ; areca nut extract (ANE) was used to induce human fibroblasts to simulate the in vitro model of fibroblasts in OSF,the experimental groups included control group ( normally cultured cells) ,ANE group ( 100 μg/ ml ANE cultured cells for 48 hours) ,ANE + low-dose Ang( 1-7) group ( 100 μg/ ml ANE + 10-7 mol /L Ang ( 1-7) cultured cells for 48 h) , ANE + high-dose Ang( 1-7) group ( 100 μg/ ml ANE + 10-5 mol /L Ang( 1-7) cultured cells for 48 h) ,immunofluorescence staining detected the expression of α-smooth muscle actin ( α-SMA) ,ELISA method detected the content of Collagen I and Collagen Ⅲ in the cell culture supernatant,MTT method detected cell proliferation activity, flow cytometry detected cell apoptosis ,the tubule formation experiment detected the vascularization of human umbilical vein endothelial cell(HUVEC) ; After the mRFP-GFP-LC3 virus was transferred to the cells,the level of autophagy was detected by immunofluorescence staining,Western blot detected the expression of autophagy-related protein Beclin-1 and the ratio of LC3-Ⅱ/ LC3-Ⅰ .
Results:
The isolated and cultured cells were in a long spindle shape,and Vimentin was positively expressed,indicating that fibroblasts were successfully isolated ; Compared with the ANE group,the fluorescence expression of α-SMA protein in ANE low dose Ang( 1-7) group and ANE + high dose Ang( 1-7) group significantly decreased,the contents of Collagen I and Collagen Ⅲ in the culture supernatant were reduced (P<0.05) ,cell proliferation activity decreased (P<0.05) ,and cell apoptosis rate increased (P < 0.05) ,the cell culture supernatants of the two groups inhibited the angiogenesis of HUVEC (P<0.05) ,endophagosomes were reduced (P<0.05) ,Beclin-1 protein expression was reduced (P <0.05) ,and the ratio of LC3- Ⅱ / LC3-Ⅰ was down-regulated (P <0.05 ) ; in addition ,the effect of ANE + high-dose Ang ( 1-7 ) group was stronger than that of ANE + low-dose Ang( 1-7) group (P<0.05) .
Conclusion
Ang( 1-7) can inhibit the activation of fibroblasts induced by ANE,promote cell apoptosis,and reduce the angiogenesis of HUVEC,this mechanism may be related to the regulation of cell autophagy.