ABSTRACT
BACKGROUND: Emodin has been shown to exert anti-inflammatory and cytoprotective effects. Our study aimed to identify a novel anti-inflammatory mechanism of emodin. METHODS: An LPS-induced model of microvascular endothelial cell (HMEC-1) injury was constructed. Cell proliferation was examined using a CCK-8 assay. The effects of emodin on reactive oxygen species (ROS), cell migration, the mitochondrial membrane potential (MMP), and the opening of the mitochondrial permeability transition pore (mPTP) were evaluated. Actin-Tracker Green was used to examine the relationship between cell microfilament reconstruction and ATP5A1 expression. The effects of emodin on the expression of ATP5A1, NALP3, and TNF-α were determined. After treatment with emodin, ATP5A1 and inflammatory factors (TNF-α, IL-1, IL-6, IL-13 and IL-18) were examined by Western blotting. RESULTS: Emodin significantly increased HMEC-1â cell proliferation and migration, inhibited the production of ROS, increased the mitochondrial membrane potential, and blocked the opening of the mPTP. Moreover, emodin could increase ATP5A1 expression, ameliorate cell microfilament remodeling, and decrease the expression of inflammatory factors. In addition, when ATP5A1 was overexpressed, the regulatory effect of emodin on inflammatory factors was not significant. CONCLUSION: Our findings suggest that emodin can protect HMEC-1 cells against inflammatory injury. This process is modulated by the expression of ATP5A1.
Subject(s)
Cell Proliferation , Emodin , Lipopolysaccharides , Up-Regulation , Emodin/pharmacology , Emodin/chemistry , Lipopolysaccharides/pharmacology , Humans , Cell Proliferation/drug effects , Up-Regulation/drug effects , Membrane Potential, Mitochondrial/drug effects , Cell Movement/drug effects , Reactive Oxygen Species/metabolism , Mitochondrial Proton-Translocating ATPases/metabolism , Mitochondrial Permeability Transition Pore/metabolism , Mitochondrial Membrane Transport Proteins/metabolism , Mitochondrial Membrane Transport Proteins/drug effects , Endothelial Cells/drug effects , Endothelial Cells/metabolism , Cell Line , Anti-Inflammatory Agents/pharmacology , Anti-Inflammatory Agents/chemistryABSTRACT
Endothelial dysfunction is a critical mediator in the pathogenesis of vascular complications of diabetes. Herein, this study was conducted to investigate the therapeutic effects of Salvianolic acid B (Sal B) on diabetes-induced endothelial dysfunction and the underlying mechanisms. Diabetic models were established both in db/db mice and high glucose (HG)-induced human umbilical vein endothelial cells (HUVECs). Moreover, HUVECs were exposed to carbonyl cyanide m-chlorophenyl hydrazone (CCCP) to induce endothelial cell damage. Following Sal B treatment, pathological changes of thoracic aorta were investigated by hematoxylin and eosin, alcian blue (AB), elastic fiber, Masson, and reticular fiber staining. BCL2-associated X (BAX), B-cell lymphoma-2 (Bcl-2), Beclin1, Parkin and PTEN Induced Kinase 1 (Pink1) expression was detected by Western blot, immunohistochemistry, and immunofluorescence in thoracic aorta, HG- and CCCP-induced HUVECs. Cell scratch test, MitoTracker Red CMXRos staining and Flou-4 AM staining were separately presented to detect migration, mitochondrial activity and intracellular Ca2+ in HUVECs. Our results showed that Sal B significantly ameliorated hyperlipidemia, hyperglycemia, hyperinsulinemia, and insulin resistance in db/db mice. Furthermore, it significantly alleviated diabetes-induced vascular endothelial dysfunction according to histopathology analysis. In diabetic thoracic aorta, HG- and CCCP-induced HUVECs, Sal B distinctly increased Bcl-2 expression and reduced BAX, Beclin1, Parkin and Pink1 expression, thereby protecting endothelial cells from apoptosis and mitophagy. Moreover, Sal B markedly enhanced migration, mitochondrial activity and intracellular Ca2+ levels both in HG- and CCCP-induced HUVECs. Collectively, Sal B exhibited a potential to improve diabetes-induced endothelial and mitochondrial dysfunction through down-regulating apoptosis and mitophagy of endothelial cells.Abbreviations: DM: diabetes mellitus; T2DM: type 2 diabetes mellitus; Sal B: Salvianolic acid B; HG: high glucose; FBG: fasting blood glucose; TC: total cholesterol; TG: triglycerides; LDL-C: low-density lipoprotein cholesterol; HDL-C: high-density lipoprotein cholesterol; FINS: fasting insulin; HOMA-IR: homeostasis model assessment insulin resistance; QUICKI: quantitative insulin-sensitivity check index; H&E: hematoxylin and eosin; HUVECs: human umbilical vein endothelial cells; IHC: immunohistochemistry; CCCP: carbonyl cyanide m-chlorophenyl hydrazone; FCM: flow cytometry; CCK-8: cell counting kit-8.