Apelin Attenuates the Osteoblastic Differentiation of Vascular Smooth Muscle Cells
نویسندگان
چکیده
Vascular calcification, which results from a process osteoblastic differentiation of vascular smooth muscle cells (VSMCs), is a major risk factor for cardiovascular morbidity and mortality. Apelin is a recently discovered peptide that is the endogenous ligand for the orphan G-protein-coupled receptor, APJ. Several studies have identified the protective effects of apelin on the cardiovascular system. However, the effects and mechanisms of apelin on the osteoblastic differentiation of VSMCs have not been elucidated. Using a culture of calcifying vascular smooth muscle cells (CVMSCs) as a model for the study of vascular calcification, the relationship between apelin and the osteoblastic differentiation of VSMCs and the signal pathway involved were investigated. Alkaline phosphatase (ALP) activity and osteocalcin secretion were examined in CVSMCs. The involved signal pathway was studied using the extracellular signal-regulated kinase (ERK) inhibitor, PD98059, the phosphatidylinositol 3-kinase (PI3-K) inhibitor, LY294002, and APJ siRNA. The results showed that apelin inhibited ALP activity, osteocalcin secretion, and the formation of mineralized nodules. APJ protein was detected in CVSMCs, and apelin activated ERK and AKT (a downstream effector of PI3-K). Suppression of APJ with siRNA abolished the apelin-induced activation of ERK and Akt. Furthermore, inhibition of APJ expression, and the activation of ERK or PI3-K, reversed the effects of apelin on ALP activity. These results showed that apelin inhibited the osteoblastic differentiation of CVSMCs through the APJ/ERK and APJ/PI3-K/AKT signaling pathway. Apelin appears to play a protective role against arterial calcification.
منابع مشابه
Vinpocetine Attenuates the Osteoblastic Differentiation of Vascular Smooth Muscle Cells
Vascular calcification is an active process of osteoblastic differentiation of vascular smooth muscle cells; however, its definite mechanism remains unknown. Vinpocetine, a derivative of the alkaloid vincamine, has been demonstrated to inhibit the high glucose-induced proliferation of vascular smooth muscle cells; however, it remains unknown whether vinpocetine can affect the osteoblastic diffe...
متن کاملGhrelin Attenuates the Osteoblastic Differentiation of Vascular Smooth Muscle Cells through the ERK Pathway
Vascular calcification results from osteoblastic differentiation of vascular smooth muscle cells (VSMCs) and is a major risk factor for cardiovascular events. Ghrelin is a newly discovered bioactive peptide that acts as a natural endogenous ligand of the growth hormone secretagog receptor (GHSR). Several studies have identified the protective effects of ghrelin on the cardiovascular system, how...
متن کاملApelin and pulmonary hypertension
Pulmonary arterial hypertension (PAH) is a devastating disease characterized by pulmonary vasoconstriction, pulmonary arterial remodeling, abnormal angiogenesis and impaired right ventricular function. Despite progress in pharmacological therapy, there is still no cure for PAH. The peptide apelin and the G-protein coupled apelin receptor (APLNR) are expressed in several tissues throughout the o...
متن کاملLiraglutide attenuates the osteoblastic differentiation of MC3T3-E1 cells by modulating AMPK/mTOR signaling
Liraglutide, a synthetic analogue of glucagon-like peptide‑1, is utilized in the treatment of type 2 diabetes and obesity. Liraglutide has been previously demonstrated to prevent osteoblastic differentiation of human vascular smooth muscle cells, resulting in the slowing of arterial calcification, however, its effect on bone formation remains unclear. The present study investigated the effect of...
متن کاملInflammation and Vascular Calcification Causing Effects of Oxidized HDL are Attenuated by Adiponectin in Human Vascular Smooth Muscle Cells
The role of oxidized high-density lipoprotein (oxHDL) and the protective effects of adiponectin in terms of vascular calcification is not well established. This study was conducted to investigate the effects of oxHDL with regards to inflammation and vascular calcification and to determine the protective role of adiponectin in attenuating the detrimental effects of oxHDL. Cell viability, mineral...
متن کامل