Saikosaponin b2 inhibits tumor angiogenesis in liver cancer via down­regulation of VEGF/ERK/HIF­1α signaling.

Saikosaponin b2 (SSb2) is an active component of Radix Bupleuri, which is commonly used in traditional Chinese medicine for defervescence and liver protection. In the present study, it was demonstrated that SSb2 exhibited potent antitumor activity by inhibiting tumor angiogenesis in vivo and in vitro. As measured by tumor weight and measures of immune function such as thymus index, spleen index and white blood cell count, SSb2 inhibited tumor growth, with low immunotoxicity, in H22 tumor­bearing mice. Furthermore, proliferation and migration of HepG2 liver cancer cells was inhibited following SSb2 treatment, which demonstrated SSb2's antitumor effect. The angiogenesis marker CD34 was downregulated in the SSb2­treated tumor samples, which suggested the antiangiogenic activity of SSb2. Furthermore, the chick chorioallantoic membrane assay demonstrated the potent inhibitory effect of SSb2 on basic fibroblast growth factor­induced angiogenesis. In vitro, SSb2 significantly inhibited numerous stages of angiogenesis, including the proliferation, migration and invasion of human umbilical vein endothelial cells. Further mechanistic studies demonstrated that SSb2 treatment reduced the levels of key proteins involved in angiogenesis, including vascular endothelial growth factor (VEGF), phosphorylated ERK1/2, hypoxia­inducible factor (HIF)­1α, MMP2 and MMP9 in H22 tumor­bearing mice, which supported the HepG2 liver cancer cell results. Overall, SSb2 effectively inhibited angiogenesis via the VEGF/ERK/HIF­1α signal pathway and may serve as a promising natural agent for liver cancer treatment.

Novel nitric oxide-releasing derivatives of triptolide as antitumor and anti-inflammatory agents: Design, synthesis, biological evaluation, and nitric oxide release studies.

A series of novel triptolide/furoxans hybrids were designed and synthesized as analogues of triptolide, which is a naturally derived compound isolated from the thunder god vine (Tripterygium wilfordii Hook. F). Some of these synthesized compounds exhibited antiproliferative activities in the nanomolar range. Among them, compound 33 exhibited both good antiproliferative activity and NO-releasing ability and the acute toxicity of compound 33 decreased more than 160 times (LD50 = 160.9 mg/kg) than triptolide. Moreover, compound 33 significantly inhibited the growth of melanoma at a low dose (0.3 mg/kg) and showed strong anti-inflammatory activity in vitro and in vivo. These results indicate that compound 33 could be a promising candidate for further study.

Effects of Evodiamine on the Pharmacokinetics of Dapoxetine and Its Metabolite Desmethyl Dapoxetine in Rats.

The objective of this work was to investigate the effect of orally administered evodiamine on the pharmacokinetics of dapoxetine and its active metabolite desmethyl dapoxetine in rats. Twelve healthy male Sprague-Dawley rats were randomly divided into 2 groups: the control group (received oral 10 mg/kg dapoxetine alone) and the combination group (10 mg/kg dapoxetine orally co-administered with 100 mg/kg evodiamine). The plasma concentration of dapoxetine and desmethyl dapoxetine were estimated by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), and different pharmacokinetic parameters were calculated using the Drug and Statistics 2.0 software. Compared to the control group, the pharmacokinetic parameter of t1/2, AUC(0-∞) and Tmax of dapoxetine in combination group was significantly increased by 63.3% (p < 0.01), 44.8% (p < 0.01) and 50.4% (p < 0.01), respectively. Moreover, evodiamine had significantly decreased the pharmacokinetic parameter of t1/2 and AUC(0-∞) of desmethyl dapoxetine. This study demonstrated that evodiamine inhibits the metabolism of dapoxetine. Henceforth, the pharmacodynamic influence of this interaction should be taken into consideration while prescribing dapoxetine to the patients already taking evodiamine.