Renal developmental retardation and the underlying mechanism induced by prenatal caffeine exposure in female fetal rats / 中国药理学通报

Aim To explore the effects of prenatal caf-feine exposure (PCE) on fetal renal growth retardation and corticosterone on the gene expression of metanephric mesenchyme stem cells.Methods Pregnant Wistar rats were administered with caffeine (30,120 mg ·kg-1) from gestational day 9 to 20.Female fetal kidney samples were collected for morphological observation and gene expression examination.The metanephric mesenchyme stem cells were harvested for cell culture,and renal related genes were detected after the treatment of corticosterone with different concentrations (250,500,1 000 μg · L-1) for 24 hours.Results Compared with the control group,the fetal kidneys in the PCE group displayed an enlarged Bowman's space and a shrunken glomerular tuft,accompanied with the repression of the gene expression of glial-cell-line-derived neurotrophic factor/tyrosine kinase receptor (GDNF/c-Ret) signaling pathway.The GDNF/c-Ret signaling pathway and angiotensin Ⅱ receptor type 1 (AT1R)/AT2R expression of metanephric mesenchyme stem cells also decreased in corticosterone groups.Conclusions PCE may induce dysplasia of female fetal kidneys.The potential mechanism is related to the repression of the gene expression of AT1R/AT2R and GDNF/c-Ret signaling pathway by PCE mediated by corticosterone in utero.

Inhibiting HSP70 expression enhances cisplatin sensitivity of cervical cancer cells / 南方医科大学学报

<p><b>OBJECTIVE</b>To investigate the relationship between sensitivity to cisplatin (DDP) and the expression of HSP70 in cervical cancer cells in vitro.</p><p><b>METHODS</b>Cervical cancer Hela229 cells treated with different concentrations of DDP and the HSP70 inhibitor (PFT-µ) were examined for cell viability using MTT assay and colony forming ability. The cell apoptosis was analyzed by flow cytometry with propidium iodide staining and DAPI staining, and JC-1 staining was used to determine mitochondrial membrane potential. The expressions of HSP70, Bcl-2, Bax and caspase-3 were measured with Western blotting. A nude mouse model bearing Hela229 cell xenograft was used to evaluate the effect of DDP and PFT-µ on tumor growth.</p><p><b>RESULTS</b>Hela229 cells expressed a higher level of HSP70 than normal cervical cells. The combined use of PFT-µ significantly enhanced the inhibitory effect of DDP (P<0.01) and increased the cell apoptosis in Hela229 cells. JC-1 staining demonstrated that DDP combined with PFT-µ more obviously reduced mitochondrial membrane potential. DDP combined with PFT-µ more strongly lowered Bcl-2 expression and increased the expressions of casepase-3 and Bax than DDP alone. In the nude mouse model, PFT-µ significantly enhanced DDP sensitivity of Hela229 cell xenografts (P<0.01).</p><p><b>CONCLUSIONS</b>Inhibition of HSP70 expression can enhance the sensitivity of cervical cancer cell to DDP both in vivo and in vitro possibly by promoting cell apoptosis, suggesting the potential of HSP70 as a new target for gene therapy of cervical cancer.</p>

MuItipIe xenobiotic metaboIism-associated cytochrome P450 isoforms might be invoIved in earIy activation of rat hepatic steIIate ceIIs in vitro / 中国药理学与毒理学杂志

OBJECTIVE To investigate the role of several xenobiotic metabolism-associated CYP450 isoforms in the auto-activation of hepatic stellate cells(HSCs) invitro. METHODS HSCs were isolated from adult Wistar rats and cultured on plastic as an in vitroauto-activation model. Positive expression of α-smooth muscle actin(α-SMA)was used as an activated marker of HSCs and detected by immunocytochemical staining in HSCs cultured for 1,2,5 or 11 d. The expressions of CYP450 isoforms were analyzed by real-time RT-PCR in the HSCs. RESULTS The immunocytochemical stai-ning showed no α-SMA expression in HSCs cultured for 1 d,while its expression gradually increased during culture since day 2. ln terms of α-SMA expression,HSCs cultured for 1,2,5,and 11 d were classified as the quiescent,early,middle and later stages of activation,respectively. The RT-PCR results revealed that CYP1B1,CYP2B1/ 2,and CYP2E1 mRNA were expressed at high levels in the early stage of HSCs activation(at day 2),which were 2.1-,1.6-,and 23.9-fold those in the quiescent HSCs(day 1),respectively. Further study revealed that mRNA expressions of these up-regulated CYPs in the early stage of activation were diminished at the subsequent two stages. The levels of CYP1A1 and CYP1A2 mRNA decreased constantly throughtout the activation process. CONCLUSION Multiple xenobi-otic metabolism-associated CYP450 isoforms might be involved in the auto-activation of rat HSCs invitro.

Expression of epoxygenases belonging to CYP2 family in rat myocardial ischemia/reperfusion injury in vivo

To elucidate the expression of epoxygenases belonging to cytochrome P-450 mono-oxygenases [CYP2] family in rat ischemic myocardium at varying reperfusion periods, and the effect of epoxygenase inhibition on the post-ischemic heart. The current study was conducted in the Department of Pharmacology, Medical College of Wuhan University, China, between September 2004 and June 2005. Rats were subjected to 40 minutes of myocardial ischemia, followed by 0, 15, 60, and 180 minutes of reperfusion. Superoxide generation was assayed by confocal microscopy, CYP2B1/2, 2C6, 2E1, 2J3 gene expressions were determined by reverse transcriptase polymerase chain reaction. Fourteen, 15-dihydroxyeicosatrienoic acid [DHET] concentration was measured by enzyme-linked immunosorbent assay. The effects of the CYP epoxygenase inhibitor N-methylsulphonyl-6-[2-propargyloxyphenyl] hexanamide [MS-PPOH] on myocardial damage and superoxide generation caused by 60 minutes of reperfusion were also evaluated. During myocardial ischemia/reperfusion, CYP2C6 and 2J3 mRNA expression were up-regulated with the peak level at 15 minutes of reperfusion; CYP2E1 gene expression decreased in a time dependent manner and reached the minimum level at 180 minutes of post-ischemia. Meanwhile, no obvious variations of CYP2B1/2 gene expression were detected during different reperfusion periods. Fourteen, 15-DHET significantly increased during reperfusion in ischemic hearts. The MS-PPOH pretreatment [15 mg/kg] effectively reduced myocardial damage and superoxide production. There are changes in gene expression of individual isozymes and an elevation of CYP epoxygenase activity involved in myocardial reperfusion injury in vivo. Epoxygenase inhibition plays a protective role in cardiac post-ischemic damage

Inhibitory effect of total flavones of Metasequsia glytostroboides on platelet aggregation and hemarheology in rats and mechanism research / 中国药理学通报

AIM: To observe the effects of total flavones of Metasequsia glytostroboides Hu et Cheng (FMG) on platelet aggregation, 5-HT release, NO contents of plasma and hemarheology in rats. METHODS: Platelet aggregation was quantified by turbidimetric method. 5-HT release was assayed by fluorescence technique. NO content of plasma was assayed by spectrophotometry. RESULTS: FMG inhibited the platelet aggregation and 5-HT release, increased the NO content of plasma, decreased the whole blood viscosity, plasma viscosity, eryrocyte electrophoresis time, K value of erythrocyte sedimentation equation and RBC, improved the hemarheology of rats. CONCLUSION: FMG can inhibit the platelet aggregation and improve the hemarheology in rats. The inhibition on 5-HT release, increase of NO contents of plasma and the inhibitory effect on Ca2+ may be its mechanisms.

Inhibitory effects of total flavones of Metasequoia glyptostroboides on experimental cardiac hypertrophy and expression of c-Fos protein in ventricle / 中草药

To observe the effects of total flavones of Metasequoia glyptostroboides Hu et Cheng (TFM) on volume-overload cardiac hypertrophy and the expression of c-Fos protein in rat. Methods　Volume-overload cardiac hypertrophy of rat was induced by aortocaval shunts. The rats were given ig TFM (400, 40 and 4 mg/kg/d). c-Fos protein in the ventricles were measured by immunocytochemical study. Results　TFM at the above dosage decreased heart weight and contents of RNA and protein in the myocardium, inhibited the expression of c-Fos protein in the ventricles. Conclusion　TFM can prevent volume-overload cardiac hypertrophy in rats. The inhibitory effects on the expression of c-Fos protein may be its mechanism in the molecular level.

Effect of total flavones isolated from Metasequoia glyptostroboides on platelet aggregation and hemorrheological properties in rats and research of its mechanism / 中草药

Object To observe the effect of total flavones isolated from Metasequoia glyptostroboides Hu et Cheng (FMG) on platelet aggregation, 5 HT of release, content of NO in plasma and hemorrheological parameters in rats. Methods Platelet aggregation was quantified by turbidimetry, release of 5 HT was assayed by fluorescence technique, and content of NO in plasma was determined by spectrophotometry. Results Inhibition of platelet aggregation and release of 5 HT, increase of NO content in plasma, as well as decrease of whole blood viscosity, plasma viscosity, red cell electrophoresis time, red cell specific volume, red cell count and K value in ESR equation were observed in the acute blood stasis rat, thereby the rat's hemorrheological properties were improved. Conclusion FMG is able to inhibit the platelet aggregation and improve the hemorrheological parameters in acute blood stasis rat. The inhibition of release of 5 HT, increase of NO content in plasma and antagonistic action of Ca 2+ may be the mechanism of its actions.

Experimental studies on blood-activating and stasis-eliminating actions of Danshensu Capsules / 中成药

Objective: To investigate the effect of Danshensu Capsules on platelet aggregation, experimental thrombosis and hemorrheology in rat. Methods : The effects of Danshensu Capsules were observed on platelet aggregation induced by ADP. Occlusive thrombotic time was determined by electrostimulating; “blood stasis” model was prepared by ice water stimulation and the main hemorheological indexes were detected. Results : Danshensu Capsules could greatly inhibit the platelet aggregation in rat induced by ADP and delay occlusive thrombosis time after electrostimulating rat common carotid artery as well as decrease whole blood viscosity, plasma viscosity, red-cell specific volume, red-cell electrophoresis time, yield stress and red-cell aggregation indexes in experimental rat with the blood stasis syndrone. The rat's hemorheological properties were improved. Conclusion : Danshensu Capsules could decrease obviously the blood state with “dense、viscosity、aggregation、coagulation” and have obvious actions of blood-activating and stasis-eliminating.