Adrenomedullin inhibits the endothelin production in-duced by urotensin Ⅱ in rat vascular smooth muscle cells

The aim of this study was to observe the effects of adrenomedullin (ADM) on endothelin (ET) production induced by urotensin Ⅱ (UⅡ) in rat vascular smooth muscle cells (VSMCs). Cultured VSMCs which were incubated with UⅡ (10-8 mol/L) and with various concentrations of ADM were used to measure the VSMCs 3H-TdR incorpora-tion, the activity of extracellular signal-regulated kinase(ERK), the amount of ET mRNA and ET production inVSMCs. In this work we found that incubation with UⅡ(10-8 mol/L) increased obviously the amount of ET mRNA inVSMCs and ET production in medium, however,co-incubation with ADM (10-10-10-8 mol/L) and UⅡ(10-8mol/L) reduced the amount of ET mRNA by 15%, 24% and45% (P< 0.01) respectively, compared with UⅡ alone. Thecontent of ET in medium was 14.13, 11.38 and 11.00 pg/mL. ADM alone (10-8 mol/L) had no effect on ET production inVSMCs. UⅡ (10-8 mol/L) promoted the 3H-TdR incorpo-ration and activity of ERK in VSMCs. ADM inhibited VSMCs 3H-TdR incorporation and activation of ERK in aconcentration-dependent manner. Compared with UⅡgroup, after co-incubation with ADM (10-10-10-8 mol/L)and UⅡ (10-8 mol/L) the VSMCs 3H-TdR incorporation wasdecreased by 7% (P > 0.05), 32% (P < 0.05) and 41% (P <0.01), respectively, and the activity of ERK was decreasedby 24% (P > 0.05), 32% (P < 0.05) and 36% (P < 0.05), re-spectively, in a concentration-dependent manner. The resultsshow that in cultured VSMCs ADM inhibits ET mRNA ex-pression, ET production and proliferation stimulated by UⅡ, and that inhibitory effect of ADM on UⅡ bioaction could be mediated through inhibiting MAPK pathway.     

Urotensin Ⅱ increases endothelin production by vascular smooth muscle cells in rats

The aim of this study was to observe the effects of urotensin Ⅱ (UII) on production of endothelin (ET) in rat aortic vascular smooth muscle cells (VSMC). Cultured VSMCs incubated with various concentrations of UII were used to measure the VSMC ³H-TdR incorporation, the amount of ET mRNA and ET production in VSMCs. In this work we found that UII (10^-10—10^-8 mol/L) promoted VSMC ³H-TdR incorporation (47%—83%, P < 0.01) and increased the amount of ET mRNA by 17.1% (P < 0.05) to 112.8% (P < 0.01), respectively, in a concentration dependent manner compared with control. After 4 and 8 h incubation, 10^-10—10^-8 mol/L of UII elevated the ET synthesis and release in a concentration dependent manner. After 4 h incubation, the content of ET in medium was 4.9, 5.36 and 7.12 pg/mL (P < 0.01). After 8 h incubation, the ET content released from VSMCs was 12.6, 12.07 and 17.17 pg/mL (P < 0.01). In addition, it was found that BQ₁₂₃, a specific ET_A receptor antagonist, obviously decreased the VSMC DNA synthesis induced by UII. The results of this study showed that UII could stimulate the ET mRNA expression and ET production in VSMC. The effects of UII on VSMC DNA synthesis were partly mediated by ET autocrine pathway. It suggests that the interaction between UII and ET plays an important biological regulating role as endogenous active peptides.     

Urotensin Ⅱ increases endothelin production by vascular smooth muscle cells in rats

The aim of this study was to observe the effects of urotensin Ⅱ (UII) on production of endothelin (ET) in rat aortic vascular smooth muscle cells (VSMC). Cultured VSMCs incubated with various concentrations of UII were used to measure the VSMC 3H-TdR incorporation, the amount of ET mRNA and ET production in VSMCs. In this work we found that UII (10-10-10-8 mol/L) promoted VSMC 3H-TdR incorporation (47%-83%, P < 0.01) and increased the amount of ET mRNA by 17.1% (P < 0.05) to 112.8% (P < 0.01), respectively, in a concentration dependent manner compared with control. After 4 and 8 h incubation, 10-10-10-8 mol/L of UII elevated the ET synthesis and release in a concentration dependent manner. After 4 h incubation, the content of ET in medium was 4.9, 5.36 and 7.12 pg/mL (P < 0.01). After 8 h incubation, the ET content released from VSMCs was 12.6, 12.07 and 17.17 pg/mL (P < 0.01). In addition, it was found that BQ123, a specific ETA receptor antagonist, obviously decreased the VSMC DNA synthesis induced by UII. The results of this study showed that UII could stimulate the ET mRNA expression and ET production in VSMC. The effects of UII on VSMC DNA synthesis were partly mediated by ET autocrine pathway. It suggests that the interaction between UII and ET plays an important biological regulating role as endogenous active peptides.     

Bojungbangdocktang inhibits vascular endothelial growth factor induced angiogenesis via blocking the VEGF/VEGFR2 signaling pathway in human umbilical vein endothelial cells

Oriental herbal medicines have been widely used for the prevention or treatment of various diseases including cancer in Asia. However, to prove their chemo preventive efficacies in modern times, scientific evidence for those herbal medicines is required. Thus, in the present study, an effective herbal cocktail Bojungbangdocktang (BJBDT) was investigated to elucidate antiangiogenic mechanism in vitro and in vivo. BJBDT significantly inhibited vascular endothelial growth factor (VEGF) induced proliferation in HUVECs at nontoxic concentrations, despite weak cytotoxicity against human umbilical vein endothelial cells (HUVECs). BJBDT also significantly suppressed VEGF-induced migration and tube formation of HUVECs. Furthermore, BJBDT treatment resulted in pale color and low hemoglobin level in Matrigel plugs, as well as dark red color and high hemoglobin level in untreated control. Interestingly, BJBDT specifically inhibited the binding of VEGF to vascular endothelial growth factor receptor 2 (VEGFR2), but not VEGFR1. In addition, friedelin, formononetin, ginsenoside Rb1, naringin, atractyloside, diosgenin, and allantonin were identified from BJBDT by high-performance liquid chromatography (HPLC) analysis as a quality of control. Taken together, these results suggest that BJBDT is a potent angiogenesis inhibitor blocking the VEGF/VEGFR2 signaling pathway in HUVECs. Supported by the Korea Science and Engineering Foundation Grant from the Korean Government (Ministry of Science and Technology) (Grant No. R13-2007-019-00000-0)