New insights into cell apoptosis and proliferation: the potential role of vaspin

Vaspin, also known as visceral adipose tissue-derived serine protease inhibitor; expression of this adipokine has been confirmed in many parts of the body like the hypothalamus, pancreas, thyroid gland, ovaries, placenta, and testes, where it may play a crucial role in osteogenesis, steroidogenesis, the formation of blood vessels, and food intake. In addition, there are many studies supporting an interaction between vaspin and cell proliferation and apoptosis, which are crucial processes for maintaining homeostasis of the body. Vaspin has an anti-apoptotic effect in ovarian cells, osteoblasts, macrophages, aortic endothelial cells, hepatocellular carcinoma cells, and cardiomyocytes. On the other hand, vaspin has no effect on apoptosis in aortic smooth muscle cells and cardiomyocytes. Interestingly, vaspin also promotes proliferation in normal and cancerous ovarian cells, pre-adipocytes, hepatocellular carcinoma cells, and bone mesenchymal stem cells, although other studies showed that this adipokine reduces the proliferation of aortic, and vascular smooth muscle cells. Furthermore, vaspin has no effect on the proliferation of chondrocytes, osteoblasts, macrophages, pre-adipocytes, umbilical vein endothelial cells, and coronary artery smooth muscle cells. Dysfunction and dysregulation in the apoptosis/proliferation ratio may lead to cancer development and progression as well as pathogenesis of many diseases. The molecular mechanism of vaspin action on cell apoptosis and proliferation is reviewed in this paper.