[Effect of alisol A 24-acetate on proliferation of aorta smooth muscle cells in rats induced by ox-LDL].

Alisol A 24-acetate, a triterpenoid extracted from Alisma orientale, has shown anti-atherosclerotic actions and many studies have proved that oxidized low density lipoprotein (Ox-LDL) could promote proliferation of aorta smooth muscle cells (VSMCs) which are closely related to atherosclerosis (AS). The purpose of this study was to evaluate the effect of alisol A 24-acetate on the proliferation of VSMCs isolated from the thoracic aorta of rats induced by ox-LDL. VSMCs were induced by ox-LDL(50 mg·L⁻¹) to establish the proliferation model and intervened by alisol A 24-acetate (5, 10, 20 mg·L⁻¹) for 12, 24 and 48 h. Then the proliferation of VSMCs was detected by MTT assay; protein expression levels of VSMCs PCNA, cyclinD1, cyclinE, p21, p27 and VSMCs PCNA, p21and p27 mRNA expression levels were detected by Western blot and Real-time polymerase chain reaction (RT-PCR) respectively. The results showed that ox-LDL could induce the proliferation of VSMCs (P<0.05), increase the protein expression levels of PCNA, cyclinD1 and cyclinE in the VSMCs (P<0.05) and inhibit the protein and mRNA expression levels of p21 and p27 (P<0.05). As compared with the model group, alisol A 24-acetate inhibited the proliferation of VSMCs in rats induced by ox-LDL and inhibited the protein expression of VSMCs PCNA, cyclinD1, cyclinE and enhanced the protein and mRNA p21 and p27 expression levels (P<0.05). The effect was more obvious with the increase of concentration of alisol A 24-acetate. These data indicate that alisol A 24-acetate can inhibit the proliferation of VSMCs induced by ox-LDL and the mechanism may be associated with inhibiting expression of cyclin protein, including cyclinD1, cyclinE, p21, p27 and so on.

Alisol A 24-Acetate, a Triterpenoid Derived from Alisma orientale, Inhibits Ox-LDL-Induced Phenotypic Transformation and Migration of Rat Vascular Smooth Muscle Cells through Suppressing ERK1/2 Signaling.

Alisol A 24-acetate, a triterpenoid extracted from Alisma orientale, has shown antiatherosclerotic actions. The purpose of this study was to evaluate the inhibition of alisol A 24-acetate on oxidized low-density lipoprotein (Ox-LDL)-induced phenotypic transformation and migration of rat vascular smooth muscle cells (VSMCs), and to explore the underlying mechanisms. VSMCs were pretreated with alisol A 24-acetate and a specific extracellular signal-regulated kinase (ERK) inhibitor, U0126, and then stimulated with 50 mg/l Ox-LDL in vitro. The expression of VSMC phenotypic marker SM22α was determined using immunocytochemistry, and the migration of VSMCs was detected using a scratch-wound healing assay. The expression of matrix metalloproteinase (MMP)-9, MMP-2, phosphorylated ERK1/2 (pERK1/2) and total ERK was determined. Ox-LDL treatment caused a reduction in SM22α expression, VSMC transformation to the synthetic phenotype, increased MMP-2 and MMP-9 synthesis, the extension of VSMC migration distance and the upregulation of pERK1/2 expression, while the addition of alisol A 24-acetate or U0126 resulted in the elevation of SM22α expression, VSMC transformation to the contractile phenotype, a reduction in MMP-2 and MMP-9 expression, the shortening of cell migration distance and decreased pERK1/2 expression. The results of this study demonstrate that alisol A 24-acetate effectively reverses the phenotypic transformation and inhibits the migration of VSMCs, which may be associated with the suppression of the ERK1/2 signaling pathway.