The Effect And Mechanism Of HSP90 In Ferroptosis Of Osteoblasts In Type 2 Diabetes Mellitus

Objective: In recent years,the living standards of people all over the world have gradually improved,and the problem of global population aging has gradually increased,and related health problems caused by various chronic diseases have become more prominent.Among them,the elderly suffer from the pain of diabetes,and type 2 diabetes bears the brunt.Diabetes is known for its serious complications in people's cognition.Osteoporosis,as a serious complication,causes a sharp decline in the quality of life of patients and may become a serious economic burden.Unfortunately,although the harm of type 2 diabetes osteoporosis is slowly increasing,its pathological mechanism has not been studied and explained.In the latest research,someone has used high-sugar to treat osteoblasts to observe the corresponding situation and functional changes of osteoblasts under different concentrations of high-sugar,and through the use of glutathione peroxidase The detection of iron death marker proteins such as 4(GPX4)has concluded that osteoblasts will impair their function through iron death under high glucose conditions.However,iron death as a new type of terminal cell injury,the specific regulation and mechanism of action in osteoblasts under high glucose conditions have not been clearly studied.In recent years,there have been many research reports on the relationship between autophagy and iron death.However,the role and regulatory mechanism of molecular chaperone autophagy and heat shock protein 90 in the process of iron death of osteoblasts caused by high glucose have not been studied yet.We believe that in the process of iron death of osteoblasts caused by high glucose and leading to diabetic osteoporosis,molecular chaperone autophagy,as a newly discovered autophagy method that degrades cytoplasmic proteins,leads to osteogenesis under high glucose conditions.One of the causes of iron death in cells,and HSP90,which regulates the degradation of cytoplasmic proteins in cells,as a kind of molecular chaperone,may be involved in the occurrence and development of diabetic osteoporosis.Under high glucose conditions,molecular chaperone autophagy can produce a large number of reactive oxygen species(ROS)and cause iron death,which in turn affects the original normal physiological activities of osteoblasts.Therefore,the research of our research group can further explain the pathological mechanism of diabetic osteoporosis,and provide new possible ideas for drug target research and treatment of diabetic osteoporosis.Methods: The research group first constructed a rat model of type 2 diabetic osteoporosis,and tested the changes of HSP90 content in the bone tissue of type 2diabetic osteoporosis rats,and then infected h FOB 1.19 cells with HSP90 lentivirus to make HSP90 knockdown and Overexpression,and use high glucose medium containing high concentration of glucose and normal medium to treat osteoblasts for several hours.At the same time,Western blot was used to detect osteogenic function-related proteins and the changes in calcium nodules stained by alizarin function to study HSP90 The effect of knockdown and overexpression on the osteogenic effects of osteoblasts.Then we used HSP90 protein functional inhibitors and iron death inhibitors to treat osteoblasts,and observed the occurrence of iron death under an electron microscope,and detected the expression of GPX4,OPG,OCN,and used flow cytometry DCFH-DA to probe The needle is used to detect the production of ROS in osteoblasts,and the MDA level of osteoblasts is detected by the interaction of malondialdehyde(MDA)and thiobarbituric acid(TBA)through a microplate reader to detect the level of MDA in osteoblasts to study HSP90 Effects on osteoblast cell viability,iron death occurrence and osteogenic function.Finally,we used the indirect immunofluorescence method to detect the distribution of lysosomal-associated membrane protein 2a(Lamp2a)in the cell and the co-immunoprecipitation method to detect the binding of HSP90 and heat shock homologous protein 70(HSC70)and HSC70 and GPX4 to observe the high glucose situation Changes in autophagy activity of molecular chaperones in lower osteoblasts.Results:(1)The content of HSP90 in the bone tissue of type 2 diabetic osteoporosis rats is increased.(2)Osteogenic function of osteoblasts is improved after HSP90 knockdown under high glucose conditions.(3)Inhibition of HSP90 function under high glucose conditions can increase the expression of GPX4.While reducing intracellular ROS,it reduces the accumulation of cellular MDA and inhibits the iron death of osteoblasts.(4)In the case of high glucose,the distribution of osteoblasts Lamp2 a increased to the perinuclear,the combination of HSP90 and HSC70 was enhanced,and the combination of HSC70 and GPX4 was enhanced.Conclusion:(1)The pathogenesis of type 2 diabetic osteoporosis rats is related to HSP90.(2)High glucose can induce osteoblasts to induce iron death through HSP90 mediation.(3)HSP90 knockdown and functional inhibition can inhibit the high glucose environment.The iron death of osteoblasts improves the osteogenic function of cells.(4)The iron death of osteoblasts induced by high glucose is induced by HSP90-mediated HSC70 molecular chaperone autophagy targeting GPX4.