| Background & objective: Ferroptosis,a new mode of cell death with a unique signaling pathway,which is a process of cell death caused by the accumulation of iron-dependent lipid peroxides.The damage of lipid peroxidation induced by excessive production of membrane lipid ROS is one of the pathological mechanisms of ulcer repair disorder.These toxic mediators such as lipid peroxides,lipid reactive oxygen species and malondialdehyde dispersed in cell membrane and organelle membrane can cause serious damage to cells.Studies have shown that diabetic ulcer wound factors have been in a high glucose environment for a long time,and excessive oxidative stress leads to ROS accumulation and activation of lipid over-oxidation,resulting in excessive apoptosis,weakening the proliferation and migration of fibrous cells and keratinocytes,damaging nerves and microvessels,inhibiting the formation of granulation tissue and epithelial cells,and seriously affecting the ability of tissue repair and regeneration.These phenomena of diabetic ulcer wound factor due to excessive oxidative stress indicate that ferroptosis may be involved in the pathological process of diabetic ulcers.Platelet-rich plasma(PRP)is a concentrated preparation of platelets,which can promote wound healing of diabetic ulcers by releasing a variety of growth factors.Therefore,the purpose of this study is to explore the relationship between platelet-rich plasma and ferroptosis in diabetic ulcer wound repair,and to reveal its potential mechanism.Methods: 1.The injury models of EA.hy926(vascular endothelial cells)and HSF(human fibroblasts)induced by high glucose were established.The appropriate concentrations of the two drugs were determined by CCK-8 method.The injured fibroblasts and vascular endothelial cells were treated with appropriate concentration of platelet-rich plasma(PRP)and ferroptosis inducer erastin,respectively.2.qPCR and Westernblot techniques were used to detect the gene and protein expression of GPX4,SLC7A11 and ACSL4 in each group.3.The levels of lipid peroxide MDA,total ROS and total SOD were detected by in situ loading probe method and colorimetric method,and the degree of lipid peroxidation damage was observed.4.The scratch test of fibroblasts(HSF)were carried out to further explore whether there is ferroptosis pathway in this cell injury model.5.The detection of CD31 and VEGF of vascular endothelial cells(EA.hy926)by qPCR and Westernblot were carried out to further explore whether there is ferroptosis pathway in this cell injury model.6.The rat model of diabetic ulcer was established,and the re-epithelialization rate of wounds in each group was observed on the 3rd,6th and 10 th day.7.qPCR and Westernblot techniques were used to detect the gene and protein expression of GPX4,SLC7A11 and ACSL4 in granulation tissue.8.The contents of SOD and MDA in ulcer tissues of each group were determined by immunohistochemical technique.9.The wound tissue was stained with HE,and the levels of inflammatory factors IL-10,IL-1βand NLRP3 in ulcer tissue were detected by ELISA method.Results: 1.In the injury model of EA.hy926(vascular endothelial cells)and HSF(human fibroblasts)induced by high glucose,compared with the control group,the expression levels of m RNA and protein of ferroptosis inhibitor GPX4 and SLC7A11 in the experiental group treated with PRP were significantly increased,while ACSL4 was significantly decreased,the lipid peroxidation products of MDA and total ROS were significantly decreased,and the SOD content was significantly increased.The cell migration rate of fibroblasts at 48 h was higher,and the m RNA and protein expression levels of VEGF and CD31 were increased in EA.HY926 cells.2.Compared with the control group,the ulcer model of diabetic rats was successfully established by injection of streptozotocin and back punching.compared with the control group,the wound healing rate of PRP intervention group was faster than that of the control group,and the expression levels of inflammatory factors IL-1 β,IL-10 and NLRP3 in the granulation tissue of ulcer wounds were lower,while the m RNA and protein expression levels of GPX4 and SLC7A11 were higher,while the expression of ACSL4 was on the contrary.At the same time,the expression of SOD was higher and MDA was lower.Conclusion: Ferroptosis is involved in the pathological process of diabetic ulcers,and PRP can inhibit ferroptosis of cells,and significantly improve the migration and regeneration ability of fibroblasts and vascular endothelial cells injured by high glucose.At the same time,PRP can reduce the inflammatory response of diabetic rats ulcer wound and promote the healing of ulcer wound. |
