PVAT targets VSMCs to regulate vascular remodelling: angel or demon.

Vascular remodelling refers to abnormal changes in the structure and function of blood vessel walls caused by injury, and is the main pathological basis of cardiovascular diseases such as atherosclerosis, hypertension, and pulmonary hypertension. Among them, the neointimal hyperplasia caused by abnormal proliferation of vascular smooth muscle cells (VSMCs) plays a key role in the pathogenesis of vascular remodelling. Perivascular adipose tissue (PVAT) can release vasoactive substances to target VSMCs and regulate the pathological process of vascular remodelling. Specifically, PVAT can promote the conversion of VSMCs phenotype from contraction to synthesis by secreting visfatin, leptin, and resistin, and participate in the development of vascular remodelling-related diseases. Conversely, it can also inhibit the growth of VSMCs by secreting adiponectin and omentin to prevent neointimal hyperplasia and alleviate vascular remodelling. Therefore, exploring and developing new drugs or other treatments that facilitate the beneficial effects of PVAT on VSMCs is a potential strategy for prevention or treatment of vascular remodelling-related cardiovascular diseases.

Total saponins from Lilium lancifolium: a promising alternative to inhibit the growth of gastric carcinoma cells.

Bulbus Lilii, as a medicinal and edible plant, has anti-inflammatory, anti-oxidative and immunopotentiating pharmacological activities, which seems to be therapeutic on cancer prevention. The purpose of this study was to investigate the effects of total saponins from Lilium lancifolium (TSLL) on proliferation, apoptosis and migration of human gastric carcinoma cells lines SGC-7901 and HGC-27 and its underlying mechanism. The results showed that TSLL inhibited the proliferation of gastric carcinoma cells by suppressing the level of proliferating cell nuclear antigen (PCNA) and increased p21 level. TSLL induced cells apoptosis by up-regulating expression of pro-apoptotic protein Bax and down-regulating anti-apoptotic protein Bcl-2 expression. Meanwhile, TSLL remarkably inhibited cell migration and invasion, decreased matrix metalloproteinase-2 (MMP-2) expression and increased tissue inhibitor of metalloproteinases-1 (TIMP-1) expression. Notably, TSLL had stronger anti-cancer effect on undifferentiated HGC-27 cells than differentiated SGC-7901 cells. Accordingly, TSLL might be a promising candidate to prevent and suppress the growth of gastric carcinoma cells.

Autophagy: a killer or guardian of vascular smooth muscle cells.

Vascular smooth muscle cells (VSMCs) is one of the main intracellular components of the blood vessel wall. The abnormalities of VSMCs participate in the development of cardiovascular diseases such as atherosclerosis, hypertension, and restenosis, especially the formation and stability of atherosclerotic plaques. Autophagy is involved in the regulation of proliferation, migration and phenotype switching of VSMCs, which in turn affects the pathological process of atherosclerosis. However, the autophagy of VSMCs has a dual effect on cells survival. Autophagy is induced in VSMCs by various stimuli such as 7-ketocholesterol (7-KC), unsaturated lipid peroxidation-derived aldehyde and excess free cholesterol, thereby promoting VSMCs survival and stabilising atherosclerotic plaque. Conversely, autophagy caused by factors such as osteopontin (OPN), angiotensin II (Ang II) and nicotine can accelerate the death of VSMCs, further accelerating atherosclerotic lesions. In addition, mitophagy and lipophagy as selective autophagy are also involved in the outcome of VSMCs as well as progression of atherosclerotic lesion. Currently, there are only a few drugs available to induce VSMCs autophagy, such as atorvastatin, telmisartan and so on. Due to the important role of VSMCs autophagy in the progression of atherosclerosis plaques, drugs that directly target autophagy of VSMCs are urgently needed to be developed.