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@#Models of acute and chronic liver injury in mice were established using carbon tetrachloride (CCl4) and ethanol to explore the protective effects of Ganoderma lucidum spore glycopeptide on liver injury.Different dosage of Ganoderma lucidum spore glycopeptide (65,130,260 mg/kg) were given by gavage.The liver index and the levels of serum aspartate transaminase (AST) and alanine transaminase (ALT) were determined.The contents of liver interleukin-6 (IL-6), tumor necrosis factor (TNF-α) and inducible nitric oxide synthase (iNOS) were tested by enzyme-linked immunosorbent assay (ELISA).The pathological injury of liver tissue was observed by HE staining.The results showed that Ganoderma lucidum spore glycopeptide could significantly reduce the liver index and the contents of serum AST and ALT in mice of acute and chronic liver injury.In mice of chronic liver injury induced by CCl4, Ganoderma lucidum spore glycopeptide could significantly decrease the contents of liver IL-6, TNF-α and iNOS, and alleviate the pathological damage of liver tissue.Results suggested that Ganoderma lucidum spore glycopeptide might reduce acute and chronic liver injury with anti-inflammatory effects in mice.
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This study was designed to investigate inhibitory effects and possible mechanisms of snake venom tripeptide (pENW) on platelet adhesion in order to promote the development of a novel anti-platelet therapy. To study the inhibitory effects of pENW on platelet adhesion, washed platelets pre-incubated with pENW (116.5-466.2 μmol x L(-1)) were used to test the ability of platelet adhesion to fibrinogen. Effect of pENW on fibrin clot retraction was also tested. Effect of pENW on platelets viability was tested by MTT assay. Effect of pENW on reactive-oxygen species (ROS) levels of platelet was studied by flow cytometry assay. Calcium mobilization in Fura-2/AM-loaded platelets was monitored with a spectrofluorimeter. Cyclic guanosine monophosphate (cGMP) and cyclic adenosine monophosphate (cAMP), thromboxane A2 (determined as its metabolite thromboxane B2) were measured using enzyme immunoassay kits. Akt, ERK and p38 phosphorylation were tested by Western blot. The results showed that pENW inhibited platelet adhesion and fibrin clot retraction in a concentration-dependent manner without cytotoxicity. Intracellular cGMP and cAMP in both resting and thrombin-activated platelets were increased by pENW. In addition, pENW attenuated intracellular Ca2+ mobilization and TXA2 production in platelets stimulated by thrombin. As shown by Western blot assay, Akt, ERK and p38 phosphorylation in thrombin-induced platelet were attenuated by pENW. However, inhibitory effects of pENW had nothing to do with ROS. Thus, pENW exhibited a significant inhibition on platelet adhesion to fibrinogen, which means pENW could block the first step of thrombosis as while as retard the more stable clot formation. The mechanisms of pENW on inhibition platelet adhesion might be related to instant regulations, such as protein kinases.
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In order to study the therapeutic time window of dimethylaminoethyl ginkgolide B mesylate(XQ-1H) in the permanent focal ischemia of rat,we used the rat model of the permanent middle cerebral artery occlusion (pMCAO).Doses of 15.6,7.8 and 3.9 mg/kg of XQ-1 H were intravenously administered at 0.5,1,2,3 h after MCAO,respectively.Neurological scores,infarct sizes,water contents and pathological changes in each interval were determined at 72 h after MCAO.It was observed that XQ-1 H administered at 0.5 and 1 h after MCAO significantly reduced the cerebral infarct size and edema,and produced significant reductions in the neurological deficits.The protective effect of XQ-1H on the neuron cells was proved by pathological observations.In addition,the contents of MDA,lactate,and the activities of SOD were measured.Reduction in the contents of MDA and lactate and enhancement in the activities of SOD were attributed to the pretreatment of XQ-1H at 0.5 and 1 h.Our results showed that the therapeutic time window of XQ-1H extended for up to 1 h after MCAO.
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Aim: To evaluate the effects of HZ08, a novel P-glycoprotein inhibitor, on reversing tumor resistance of K562/ADM to adriamycin in nude mice and on the activities of cytochromes P-450 (GYP) isoforms. Methods: Nude mice bearing K562/ADM were injected at different doses of HZ08 with adriamycin for 4 weeks. The tumor weights of HZ08 treatment groups were determined and compared to those of the control and positive groups. In addition, the effects of HZ08 were examined on GYP isoforms-mediated metabolism of specific substrates by GYP isoforms in rat liver microsomes in the presence or absence of HZ08. Results: The tumor weights of HZ08 treatment groups were significantly decreased and HZ08 was a relatively potent inhibitor of CYP3A4, with no significant effects on other isoforms tested. Conclusion: HZ08 has potent effects on reversing P-glycoprotein mediated tumor multidrug resistance in rive with little influence on cytoehrome P-450 activities of rat liver.
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AIM: To study the effect of Lomerizine on the activity of P-glycoprotein (P-gp) in the bloodbrain barrier(BBB) and search for novel effective P-gp inhibiting agent against multidrug resistance. METH-ODS: Rhodamine123 (Rh123) was used to examine the activity of P-gp and RT-PCR to study the mdr mRNA expression in cultured rat brain microvessel endothelial cells (RBMECs). RESULTS: Lomerizine could increase the cellular Rh123 in RBMECs in a concentration-dependent manner. RT-PCR indicated that lomerizine could not down-regulate the expression of mdr mRNA. CONCLU-SION: Lomerizine can reverse multidrug resistance in the blood-brain barrier by inhibiting the activity of P-gp.KEY WORDS lomerizine; P-glycoprotein; bloodbrain barrier; RT-PCR
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AIM: To observe protective effects of sanguis draxonis flavones on myocardial ischemia in rats and dogs. METHODS: Acute myocardial ischemia in rats was produced by iv pituitrin and ECG indexes were observed. Myocardial ischemia was induced by ligating coronary artery in anaesthetized dogs, and then EEC, CK,LDH, and LD in serum were determined respectively. RESULTS: J point and T wave in rats changed evidently after iv pituitrin, which was reversed by sanguis draxonis flavones (360, 180 mg?kg~ -1). In coronary artery ligation model, infraction range, △N-ST, △?-ST and some serum indexes (such as CK, LDH and LD) was decreased after ig sanguis draxonis flavones (120, 60, 30 mg?kg~ -1). CONCLUSION: Acute myocardial ischemia is protected effectively by sanguis draxonis flavones.