Continuous synthesis and anti-myocardial injury of tanshinone IIA derivatives.

A series of tanshinone IIA derivatives were synthesized through sulfonation, slat-forming, chlorination, and amidation reactions. Meanwhile, anti-myocardial injury activity was evaluated in vitro. D8 and D9 exhibited a slightly higher anti-myocardial injury (5.78, 7.46 µM) activity compared with esmolol (8.12 µM). In addition, they also displayed a concentration-dependent inhibition on the anti-myocardial injury.

Pharmacokinetics, Metabolism and Disposition of [14C]XQ-1H After Intravenous Administration to Male Rats.

OBJECTIVE: This study describes the in vivo pharmacokinetics and metabolism of [14C]labeled XQ-1H in male rats. METHODS: XQ-1H is a methanesulfonate of XQ, 10-O-(N,N-dimethylaminoethyl)-ginkgolide B, a derivative of ginkgolide B (GB) with enhanced water solubility. Since it is very difficult to synthesize radiolabeled GB, the results obtained in this study may provide helpful insight to further ADME investigation of GB and its analogue compounds. After an i.v. administration of [14C]XQ-1H to male rats, XQ (the freebase form of XQ-1H) was extensively hydrolyzed, moderately metabolized, and mainly excreted in feces (71.5% of the dose) via the biliary route. RESULTS: The main enzyme mediated metabolic pathways were mono- and di-demthylation. Using the radiolabel form of XQ-1H, the temporal binding of XQ to red blood cells was observed. CONCLUSION: Binding of XQ to RBCs may lower the blood's viscosity and thus provide symptomatic improvement of ischemic stroke patients.

Sodium tanshinone IIA silate inhibits high glucose-induced vascular smooth muscle cell proliferation and migration through activation of AMP-activated protein kinase.

The proliferation of vascular smooth muscle cells may perform a crucial role in the pathogenesis of diabetic vascular disease. AMPK additionally exerts several salutary effects on vascular function and improves vascular abnormalities. The current study sought to determine whether sodium tanshinone IIA silate (STS) has an inhibitory effect on vascular smooth muscle cell (VSMC) proliferation and migration under high glucose conditions mimicking diabetes without dyslipidemia, and establish the underlying mechanism. In this study, STS promoted the phosphorylation of AMP-activated protein kinase (AMPK) at T172 in VSMCs. VSMC proliferation was enhanced under high glucose (25 mM glucose, HG) versus normal glucose conditions (5.5 mM glucose, NG), and this increase was inhibited significantly by STS treatment. We utilized western blotting analysis to evaluate the effects of STS on cell-cycle regulatory proteins and found that STS increased the expression of p53 and the Cdk inhibitor, p21, subsequent decreased the expression of cell cycle-associated protein, cyclin D1. We further observed that STS arrested cell cycle progression at the G0/G1 phase. Additionally, expression and enzymatic activity of MMP-2, translocation of NF-κB, as well as VSMC migration were suppressed in the presence of STS. Notably, Compound C (CC), a specific inhibitor of AMPK, as well as AMPK siRNA blocked STS-mediated inhibition of VSMC proliferation and migration. We further evaluated its potential for activating AMPK in aortas in animal models of type 2 diabetes and found that Oral administration of STS for 10 days resulted in activation of AMPK in aortas from ob/ob or db/db mice. In conclusion, STS inhibits high glucose-induced VSMC proliferation and migration, possibly through AMPK activation. The growth suppression effect may be attributable to activation of AMPK-p53-p21 signaling, and the inhibitory effect on migration to the AMPK/NF-κB signaling axis.

Sodium tanshinone IIA silate inhibits oxygen-glucose deprivation/recovery-induced cardiomyocyte apoptosis via suppression of the NF-κB/TNF-α pathway.

BACKGROUND AND PURPOSE: Inhibition of apoptosis may attenuate the irreversible injury associated with reperfusion. In the current study, we focused on the cytoprotective effects and the underlying mechanism of sodium tanshinone IIA silate (STS) against damage induced by oxygen-glucose deprivation/recovery (OGD/R). in H9c2 cardiomyocytes and the underlying mechanisms. EXPERIMENTAL APPROACH: We used a model of cardiac ischaemia/reperfusion, OGD/R in H9c2 cardiomyocytes, to assess the cardioprotective effects of STS. Apoptosis of cells was measured with Hoechst 33342-based fluorescence microscopy, and annexin V-FITC-based flow cytometry. Caspase-3 and caspase-8 activities and mitochondrial membrane potential were also measured using commercial kits. TNF-α in the cell culture supernatant fractions were measured with sandwich elisa, and protein levels assayed using Western blot. KEY RESULTS: STS inhibited OGD/R-induced apoptosis by suppressing JNK-mediated activation of NF-κB, TNF-α expression, activation of caspase-3 and caspase-8 and the Bax/Bcl-2 ratio. Additionally, positive feedback between NF-κB and TNF-α and amplification of TNF-α were inhibited, suggesting that STS plays a protective role against apoptosis in cardiomyocytes, even upon activation of pro-inflammatory cytokines. Interestingly, the cytoprotective effects of STS on OGD/R-induced apoptosis and promotion of cell survival were attenuated after inhibition of PI3K. CONCLUSION AND IMPLICATIONS: The inhibitory effects of STS on TNF-α and positive feedback signalling of the NF-κB/TNF-α pathways may play important roles in myocardial protection against ischaemia/reperfusion. These protective effects of STS are mediated by suppressing JNK activity through activation of the PI3K-Akt pathway.

The synthesis and biological evaluation of 10-O-dialkylaminoethyl ginkgolide B as platelet-activating factor antagonist.

Four nitrogen-containing derivatives of ginkgolide B were synthesized to improve the physical-chemical properties and bioavailability of ginkgolide B. The reaction was accomplished with the nitrogen atom as neighboring group participating in the replacement reaction. All of the four compounds were proved to have excellent inhibiting effect on rabbit platelet aggregation induced by platelet-activating factor which is as well as ginkgolide B.