Tetramethylpyrazine and paeoniflorin combination(TMP-PF)inhibits angiogenesis in atherosclerosis via miR-126/VEGF/VEGFR2 signaling pathway

Angiogenesis in atherosclerosis(AS)promotes plaque destabilization.miR-126 has a significant role in angiogenesis.Tetramethylpyrazine(TMP)and paeoniflorin(PF)have anti-atherosclerotic effects.However,the miR-126-related mechanisms of TMP and PF combination(TMP-PF)on angiogenesis in AS have not been understood.To explore the mechanism of TMP-PF on angiogenesis in AS targeting miR-126.Human umbilical vein endothelial cells(HUVECs)were assigned into the control,model,TMP-PF,TMP-PF+miR-126 inhibitor,and simvastatin groups.HUVECs were transfected with miR-126 inhibitor or negative control,incubated with oxidized low-density lipoprotein(ox-LDL)to establish AS model,and then treated with TMP-PF or simvastatin.Cell proliferation,migration,and tube formation assays are conducted,and the expression of angiogenesis-related factors were detected by enzyme-linked immunosorbent assay(ELISA)and Western blotting.The expression level of miR-126 was confirmed by polymerase chain reaction(PCR).0x-LDL promoted HUVECs proliferation,migration,and tube formation,downregulated miR-126 expression,and increased the expression of VEGF,VEGFR2,bFGF,and FGFR1.TMP-PF inhibited proliferation,migration,and tube formation,upregulated miR-126 expression and decreased the expression of VEGF,VEGFR2,bFGF,and FGFR1 in ox-LDL-induced HUVECs.However,the effects of TMP-PF on angiogenesis and the expression of miR-126,VEGF,VEGFR2,and FGFR1 were abolished by miR-126 inhibitor.TMP-PF suppressed angiogenesis in AS by regulating miR-126/VEGF/VEGFR2 pathway,which might elucidate the underlying mechanism of TMP-PF in alleviating AS.

The molecular mechanism underlying angiogenesis in hepatocellular carcinoma: the imbalance activation of signaling pathways

OBJECTIVE: To explore the effect of two dominating signaling pathways, VEGF/KDR and angiopoietins/Tie2, on the formation of new blood vessel in hepatocellular carcinoma (HCC) growth and metastasis. METHODS: RT-PCR and Western blot were employed to evaluate the VEGF/KDR and angiopoietins/Tie2 expression in samples from 23 patients with HCC. Meanwhile, microvessel density (MVD) was determined as a marker of angiogenesis by counting CD34 positive cells with the method of immunohistochemistry. RESULTS: The two pathways were activated in all HCC samples. The expressions of vascular endothelial growth factor (VEGF) and angiopoietin-2 (Ang2) were significantly higher (P<0.05) in hepatocellular carcinoma tissues and the margin of the tumor than those in control groups, and so did CD34 positive cells. Although significant difference in the expression of kinase insert domain containing receptor (KDR) and Ang1/Tie2 was not observed in all groups, their distinct high levels were seen in hepatoma and its margin compared with normal and cirrhotic liver. VEGF and Ang2 expressions were seen up-regulated in HCC with vascular invasion and satellite lesion. CONCLUSIONS: The two signaling pathways, VEGF/KDR and angiopoietins/Tie2 are activated in the process of angiogenesis in HCC and modulate the formation of new blood vessels. The imparity of the two signaling pathways' activation is to benefit HCC metastasis. In the two pathways, VEGF and Ang2 may play an important role in the process of angiogenesis, and are necessary indicators for the prognosis and metastasis of HCC. This study provides another clue for the exploration of anti-angiogenic agents.