7050 Effect of Spironolactone On Reducing Sugar-Induced Cellular Damage In MC3T3-E1 Osteoblastic Cells

Abstract Disclosure: S. Yun: None. H. Sang: None. S. Park: None. K. Suh: None. H. Kim: None. S. Chin: None. Background: In diabetes, prolonged hyperglycemia causes oxidative stress, resulting in pancreatic beta cells' dysfunction and diabetic complications. Oxidative stress can inhibit osteoblast differentiation and induce dysfunction and apoptosis. Spironolactone is an aldosterone antagonist used to treat hypertension and heart failure. In this study, we observed whether spironolactone can reduce osteoblast cytotoxicity and differentiation caused by oxidative stress induced by 2-deoxy-d-ribose (dRib). Methods: MC3T3-E1 cells were treated with spironolactone (0-100 uM) in the presence of 15 mM dRib. The cytotoxicity (lactate dehydrogenase, LDH) and differentiation (collagen content, alkaline phosphatase [ALP] activity, and mineralization) of osteoblasts, inflammatory cytokines (tumor necrosis factor-α [TNF-α], interleukin [IL]-6), oxidative stress (reactive oxygen species [ROS], mitochondrial superoxide), endoplasmic reticulum (ER) stress (activating transcription factor 6 [ATF-6], inositol-requiring 1 [IRE1]), mitochondrial function (mitochondrial membrane potential [MMP], adenosine triphosphate [ATP]), glyoxalase I activity, and glutathione (GSH) were measured. Results: Pretreatment of MC3T3-E1 osteoblastic cells with spironolactone prevented the dRib-induced cytotoxicity of osteoblasts and promoted differentiation of osteoblasts suppressed by dRib. Spironolactone significantly reduced dRib-induced inflammatory cytokines, ROS, mitochondrial superoxide, and ER stress. dRib-induced mitochondrial dysfunction was significantly improved by treatment with spironolactone. dRib is detoxified by the glyoxalase system. Pretreatment with spironolactone also increased the level of reduced GSH and the activity of glyoxalase I in dRib. Conclusion: Spironolactone could reduce dRib-induced cytotoxicity and promote differentiation in MC3T3-E1 osteoblastic cells by reducing oxidative stress and inflammatory cytokines, increasing mitochondrial biogenesis, and detoxifying dRib. These results suggest that spironolactone can be useful in the prevention and treatment of diabetic bone disease. Presentation: 6/1/2024