Vaspin attenuates the apoptosis of human osteoblasts through ERK signaling pathway

Abstract

It has been hypothesized that adipocytokines originating from adipose tissue may have an important role in bone metabolism. Vaspin is a novel adipocytokine isolated from visceral white adipose tissue, which has been reported to have anti-apoptotic effects in vascular endothelial cells. However, to the best of our knowledge there is no information regarding the effects of vaspin on osteoblast apoptosis. This study therefore examined the possible effects of vaspin on apoptosis in human osteoblasts (hOBs). Our study established that vaspin inhibits hOBs apoptosis induced by serum deprivation, as determined by ELISA and TUNEL assays. Western blot analysis revealed that vaspin upregulates the expression of Bcl-2 and downregulates that of Bax in a dose-dependent manner. Vaspin stimulated the phosphorylation of ERK, and pretreatment of hOBs with the ERK inhibitor PD98059 blocked the vaspin-induced activation of ERK, however, vaspin did not stimulate the phosphorylation of p38, JNK or Akt. Vaspin protects hOBs from serum deprivation-induced apoptosis, which may be mediated by activating the MAPK/ERK signaling pathway.

Novel Adipokines and Bone Metabolism

“…The researches about vaspin were mainly focused on the insulin resistance [77], hepatitis disease [78, 79], and cardiovascular disease [80, 81]. Presently, our previous study showed that the vaspin could inhibit the apoptosis of the osteoblasts [82]. However, no report about its function in osteogenesis, osteoclastogenesis as well as the relation with BMD was published.…”

Vaspin prevents elevation of blood pressure through inhibition of peripheral vascular remodelling in spontaneously hypertensive rats

“…Vaspin was strongly expressed at the peak of obesity and insulin resistance (Hida et al 2005). It was recently reported that vaspin inhibited serum deprivationinduced apoptosis in human osteoblasts (Zhu et al 2013). Thus, it is considered that vaspin may be involved in pathogenesis of metabolic disorders including obesity and diabetes as well as bone metabolism.…”

Waspina a wybrane wykładniki stanu kośćca u dziewcząt z jadłowstrętem psychicznym

“…Hence the final conclusion that vaspin downregulates osteoclastogenesis in part by inhibiting expression of the transcription factor NFATc1 [28]. Vaspin also attenuated the apoptosis of human osteoblasts [29]. Western blot analysis indicates that, depending on the dose, vaspin upregulates the expression of anti-apoptotic gene Bcl-2 and downregulates the expression of BAX, which plays a crucial role in apoptosis induction.…”

“…Kamio et al [28] concluded that vaspin inhibited RANKL-induced osteoclastogenesis in RAW264.7 cells and bone marrow cells. It also attenuated the apoptosis of human osteoblasts [29]. Hence the hypothesis that changes in vaspin levels observed in girls with AN [22] might play a role in inducing changes in bone metabolism found in these patients, the effect of which might be mediated by the RANKL/RANK/OPG system.…”