Gualou Xiebai Decoction prevents myocardial fibrosis by blocking TGF-beta/Smad signalling.

OBJECTIVES: The present study is aimed to investigate the effect of Gualou Xiebai Decoction (GXD) ethanol extract on myocardial fibrosis and clarify the possible mechanism. METHODS: Rats with ligated left anterior descending coronary artery were treated with GXD ethanol extract (1.14 g/kg, 2.27 g/kg, 4.53 g/kg) daily via gavage for 4 weeks. Histopathological changes and collagen distribution were evaluated by haematoxylin and eosin and Masson staining. The mRNA levels of Collagen I and Collagen III were detected by real-time PCR. The expressions of TGF-ß1, TGFß receptor (TGFßR)I, TGFßRII, P-Smad2/3 and Smad7 were determined by Western blot. RESULTS: GXD treatment was significantly reduced the heart weight/body weight ratio (P < 0.05) as well as the left ventricle weight/body weight ratio (P < 0.05). It also significantly alleviated the degree of inflammation, decreased myocardial collagen volume fraction (P < 0.05 ∼ 0.01), together with markedly prevented the upregulations of Collagen I and Collagen III (P < 0.05 ∼ 0.01). Moreover, GXD downregulated expressions of TGF-ß1, TGFßRI, TGFßRII, Smad2/3 whereas improved Smad7 expression in the myocardial fibrosis rats. CONCLUSIONS: GXD ameliorates myocardial fibrosis induced by cardiac infarction with ligated left anterior descending coronary artery, the mechanism maybe involve in inhibiting the TGF-ß1 signalling pathway.

Effect of Liangxuehuayu Recipe on hemorheology in rats with blood stasis syndrome.

OBJECTIVE: To investigate the effects of Liangxuehuayu Recipe on hemorheology in rats with blood stasis syndrome induced by mutifactor stimuli. METHODS: SD rats were divided into control, model, Liangxuehuayu Recipe (high, middle and low dose, 18, 9, 4.5 g/kg accordingly). Except the control group, blood stasis model was established in the rest groups. The hemorheological parameters were measured and compared. RESULTS: Blood viscosity at high, moderate and low level in rats with blood stasis significantly increased (P<0.05), but blood viscosity at high level and plasma viscosity was significantly decreased in rats induced by some stimuli after Liangxuehuayu Recipe were intra-gastrically administered for 1 weeks (P<0.01, P<0.05). CONCLUSIONS: Liangxuehuayu Recipe is effective in improving hemorheology, and has important application value in the prevention of occurrence and development of ischemic stroke.

Influence of cyclovirobuxine D on intracellular [Ca(2+)] regulation and the expression of the calcium cycling proteins in rat myocytes.

Our previous studies have shown that cyclovirobuxine D (CVB-D) ameliorated the cardiac function in heart failure rats. Considering the relationship between cardiac function and [Ca(2+)]i, and the role of calcium cycling on regulating [Ca(2+)]i, the present study was designed to evaluate the influence of CVB-D on the calcium transient of myocytes from neonatal rats and adult heart failure (HF) rats. The expression of calcium cycling proteins, including L-type calcium channel (LTCC), ryanodine receptor 2 (RYR2), sarcoplasmic reticulum calcium ATPase 2a (SERCA2a) and sodium-calcium exchanger (NCX), were investigated to explore the underlying mechanism. CVB-D increased the intensity of calcium transient, accelerated the process of calcium transient and attenuation in the neonatal and adult myocytes. Furthermore, CVB-D shortened T(peak) and T(attenuation) in the adult myocytes and slowed down the heart rate of neonatal myocytes. Besides, CVB-D increased the expression of RYR2 and SERCA2a, decreased the expression of NCX, but showed no significant effect on LTCC. Thus, it was concluded that CVB-D increased the release and uptake of Ca(2+) in systolic and diastolic period, respectively. CVB-D might not only facilitate the utilization of intracellular Ca(2+), but also prevent the loss of Ca(2+).

[Protective effect of TGF-beta-Smads signal-based oxymatrine on myocardial fibrosis induced by acute myocardial infarction in rats].

OBJECTIVE: To study the protective effect of oxymatrine (OMT) on myocardial fibrosis induced by acute myocardial infarction in rats and its effect on TGF-beta-Smads signal pathway. METHOD: Arteria coronaria ligation-induced acute myocardial infarction model was established in rats. The survived rats were randomly allotted into the model group, 50, 25, 12.5 mg x kg(-1) OMT groups, the 50 mg x kg(-1) captopril group, and the Sham-operated group which was treated as the model group without the arteria coranaria ligation. After 8 weeks of ligation, myocardial fibrosis was detected by HE and Masson staining, and the RT-PCR method were used to detect the expression of mRNA of TGF-beta-Smads signal system. RESULT: The histopathological examination showed decrease in cardiocytes, deposition of extra-cellular matrix, and increase of collagen contents after 8 weeks of ligation. RT-PCR results showed that mRNA expressions of TGF-beta1, TbetaR1, Smad2, Smad3 and Smad4 significantly increased, but mRNA expression of Smad7 is remarkable lower than the sham-operated group. Treatment with OMT for 8 weeks could remarkably inhibit myocardial fibrosis, decrease mRNA expressions of TGF-beta1, TbetaR1, Smad2, Smad3, and Smad4, and increase mRNA expressions of Smad7. CONCLUSION: OMT has the inhibitory effect on the experimental myocardial fibrosis induced by AMI in rats. Its mechanism may be closely related to TGF-beta-Smads signal system.

[Effect of electroacupuncture combined with intragastric administration of borneol on the permeability of blood-brain barrier in the mouse].

OBJECTIVE: To observe the effect of electroacupuncture (EA) combined with gavage of borneol on the permeability and ultrastructure of the blood-brain barrier (BBB) in mice, so as to reveal its mechanism underlying improving permeability of BBB. METHODS: For assaying Evans blue (EB) content in the brain, 60 Kunming mice were evenly divided into control, EA, borneol (0.2 g/kg, borneol-0.2), borneol (0.4 g/kg, borneol-0.4), borneol (0.2 g/kg, borneol-0.2) + EA and borneol (0.4 g/kg, borneol-0.4) + EA groups. For determination of P-glycoprotein [P-gp, a member of the superfamily of ATP-binding cassette (ABC) transporters which transport various molecules across extra- and intra-cellular membranes] function and the ultrastructure of BBB, other 84 mice were randomized into control, borneol-0.2, borneol-0.4, borneol-0.2 + EA, borneol-0.4 + EA and verapamil groups (n=10 for P-gp. function analysis, and n 2 for electron microscopic observation). EA (2 Hz, 1 mA) was applied to "Baihui" (GV 20) and "Yamen"(GV 15) for 20 ml once daily for 14 days. EB (2.5%, 0.2 mL/kg) and rhodamine (Rh) 123 (0.2 mg/kg) were injected intravenously first through the tail vein, and their contents in the brain and Rh 123 in the plasma were detected after EA by using an ultraviolet fluorescence microplate reader. At the same time, the permeation index (Kp) was calculated by the ratio of Rh 123brain/Rh 123blood. RESULTS: Compared with the control group, the cerebral EB and Rh 123 contents and Kp of BBB in the EA, borneol-0.2, borneol-0.4, borneol-0.2 + EA, borneol-0.4 + EA and verapamil groups were increased significantly (P < 0.05, P < 0.01). The cerebral EB content was significantly higher in the borneol-0.2 + EA group than in the borneol-0.2 group (P < 0.05), suggesting a synergistic effect of EA and borneol. No significant differences were found among the EA, borneol-0.2 and borneol-0.4 groups in cerebral EB levels, among the control, EA, borneol-0.2, borneol-0.4, borneol-0.2 + EA, borneol-0.4 + EA and verapamil groups in plasma Rh 123 contents, and among the EA, borneol-0.2, borneol-0.4, borneol-0.2 + EA, borneol-0.4 + EA and verapamil groups in cerebral Rh 123 contents and Kp of BBB (P > 0.05). Results of the electron transmission microscope showed that the compact degree of the tight junction of BBB was decreased in the borneol-0.2, borneol-0.4, borneol-0.2 + EA, borneol-0.4 + EA groups but not in the EA group. CONCLUSION: EA and gavage of borneol treatments may enhance the permeability of BBB for EB and Rh 123 and have a certain synergistic effect in mice. The effect of borneol may be closely with the inhibition of P-glycoprotein and the decrease of tight junction of BBB while the effect of EA treatment is probably related to the inhibition of P-glycoprotein only.

[Protective effects of erythromycin on human bronchial epithelial cells impaired by interleukin-4].

OBJECTIVE: To study the protective effects and mechanisms of erythromycin on human bronchial epithelial (HBE) cells damaged by interleukin-4. METHODS: The growth curve of HBE cells was recorded by MTT. The cells were divided into the following groups: control (incubation for 24, 48 h); IL-4 (0.01 mg/L, incubation for 24, 48 h); erythromycin intervention group 1 (4 mg/L erythromycin co-incubation for 24, 48 h after adding IL-4) and erythromycin intervention group 2 (40 mg/L erythromycin co-incubation for 24, 48 h after adding IL-4). The mitotic cycle of HBE cell was determined by flow cytometry and its apoptosis examined by Hoechst dyeing. RESULTS: The viability of HBE cells was significantly enhanced after a 24/48-hour treatment of erythromycin as compared with IL-4 group (P < 0.05, P < 0.01). In erythromycin intervention group 1, the cell ratios of G(0)/G(1) and S phases were (55.9 ± 2.5)% and (34.7 ± 3.4)% respectively while the rate of cell apoptosis was (9.5 ± 0.9)%. There were significant differences as compared with IL-4 group (P < 0.05). In erythromycin intervention group 2, the cell ratios of G(0)/G(1) and S phases were (55.1 ± 0.5)% and (36.2 ± 2.7)% respectively while the rate of cell apoptosis was (4.0 ± 0.6)%. There were significant differences as compared with IL-4 group (P < 0.05). CONCLUSION: Erythromycin has protective effects on HBE cells damaged by IL-4. The mechanism is probably through influencing the mitotic cycle and inhibiting the apoptosis.

Ubiquitination of heat shock protein 27 is mediated by its interaction with Smad ubiquitination regulatory factor 2 in A549 cells.

Smad ubiquitination regulatory factor 2 (Smurf2) is a crucial part of the ubiquitin-proteasome pathway (UPP) that regulates cellular signal transduction via ubiquitin-dependent degradation of some substrates and receptors. The biological function of Smurf2 in lung diseases, however, is not clear. In this study, the authors found that overexpression of Smurf2 altered the subcellular localization and distribution of heat shock protein 27 (HSP27), and induced a decrease of HSP27 protein levels through HSP27 degradation by the UPP in human lung adenocarcinoma epithelial cell line A549. Colocalized assay using confocal microscopy and coimmunoprecipitated reciprocally by either antibody indicated the interaction between Smurf2 and HSP27, which suggested that Smurf2 mediated ubiquitylation-dependent degradation of HSP27 through their interaction in A549 cells.

[Influence of electroacupuncture plus intragastric administration of extract of hypericum perforatum L on ethology and brain microcirculation in depression rats].

OBJECTIVE: To observe the effect of combined administration of intragastric perfusion of extract of Hypericum Perforatum L (HP-L) and electroacupuncture (EA) of "Baihui" (GV 20) and "Yamen" (GV 15) on behavior and brain microcirculation in depression rats. METHODS: Female SD rats were randomized into control, model, lower-dose of HP-L (lower-dose in short, 10 mg/kg), lower-dose+ EA, higher-dose (20 mg/kg) and higher-dose+ EA groups (n = 10/group). Depression model was established by lonely raising and chronic unpredictable mild stress (tail cramping, water-deprivation, fasting, electrical shock stimulation, etc. ) for 21 days. EA (2 Hz, 1 mA) was applied to "Baihui"(GV 20) and "Yamen"(GV 15) for 20 min, once daily for 14 days. Changes of ethology including glucose-consumption during 1 h, crossing and rearing scores of open-field test during 3 min (for assessing the rats' locomoto)and laser Doppler flowmetry values of cortical regional cerebral bloodflow (r CBF) were detected, and Morris water maze test (for assessing the rats' learning-memory ability) was conducted. RESULTS: In comparison with the control group, the sucrose consumption, crossing and rearing scores of open-field test, the average swimming velocity (ASV). the ratios of path length and swimming duration near the hidden-platform and the path length and swimming duration far from the platform of Morris water maze test during 70 seconds, and the cortical r CBF value in the model group were decreased significantly (P < 0.01), while the total swimming distance and escape latency in the model group increased apparently (P < 0.01). Compared to the model group, the average sucrose consumption, crossing and rearing scores of open-field test, the ASV, and the ratios of path length and swimming duration near the platform and those far from the platform in the lower-dose. lower-dose + EA, higher-dose and higher-dose + EA groups, and the cortical r CBF in the lower-dose + EA and higher-dose + EA groups were increased considerably (P < 0.05, P < 0.01). The total swimming distances and escape latencies of lower-dose, lower-dose + EA, higher-dose and higher-dose + EA groups were significantly shortened in comparison with the model group (P < 0.05, P < 0.01). The sucrose consumption and crossing score were significantly higher in the higher-dose + EA group than the lower-dose group (P < 0.05). The escape latency was significantly shorter in the higher-dose + EA group than in the lower-dose group (P < 0.05). No significant differences were found among the lower-dose, lower-dose + EA and higher-dose groups the sucrose consumption, crossing score and escape latency: among the lower-dose, lower-dose + EA, higher-dose and higher-dose + EA groups in the rearing score and ASV; among the lower-dose, higher-dose and model groups in the cortical r CBF (P > 0.05). CONCLUSION: EA can enhance the effect of extract of HP-L in increasing sucrose consumption, crossing score and cerebral blood flow, and in shortening escape latency in depression rats, which may contribute to their effect in improving depression. But HP-L itself has no effect on cortical microcirculation.

Beneficial effect of Cyclovirobuxine D on heart failure rats following myocardial infarction.

The effect of Cyclovirobuxine D, an active ingredient from Buxus microphylla, was investigated in the potential prevention of cardiac dysfunction in rats with congestive heart failure. Heart failure was induced by left coronary artery occlusion and verified using echocardiography. Cyclovirobuxine D was administered for 30 days (0.5, 1.0 and 2.0mg/kg, ig) and mortality, cardiac function, hemodynamics, microcirculation, histology and ultrastructure assessments were observed. Results from the present study suggest that Cyclovirobuxine D is beneficial for heart failure induced by myocardial infarction and supports the potential for Cyclovirobuxine D as a new therapy for heart failure.

Emodin-induced microglial apoptosis is associated with TRB3 induction.

Emodin (1,3,8-trihydroxy-6-methylanthraquinone), a natural anthraquinone compound isolated from the rhizome of rhubarb, has been reported to treat brain injury after intracerebral hemorrhage. Treatment of neurons with emodin is able to decrease glutamate excitotoxicity, modulate calcium homeostasis, and induce Bcl-2 expression. However, the effects of emodin on the brain-resident innate immune cells are unclear. In the present study, the mouse microglial cell line, BV-2, was selected to investigate the effects of emodin on microglial activation and apoptosis. Cell viability and apoptosis were sequentially measured with the CellTiter-Glo Luminescent Cell Viability Assay, YOPRO-1 and Caspase-Glo 3/7 Assay Systems. The degree of microglial activation was evaluated using quantitative RT-PCR to measure expression of inflammatory markers. Treatment of BV-2 cells with emodin caused caspase-mediated apoptosis in a dose-dependent manner, and emodin augmented LPS-induced microglial apoptosis to repress inflammatory activation. In response to emodin treatment, reactive oxygen species (ROS) production was increased, and TRB3 was markedly activated. siRNA knockdown of TRB3 attenuated emodin-induced microglial apoptosis. Ectopic overexpression of TRB3 decreased cell viability and was associated with dysregulation of the prosurvival Akt/FOXO3 pathway. These results demonstrate that emodin induces BV-2 cell apoptosis through TRB3 and consequently eliminates inflammatory microglia. Our findings provide a novel molecular basis through which emodin exerts neuroprotective effects, treating brain injury after intracerebral hemorrhage.

[Effects of CVB-D on hemodynamic in anaesthetized dogs in vivo].

OBJECTIVE: To investigate hemodynamic in anaesthetized dogs after the intravenous injection of cyclovirobuxine D (CVB-D). METHODS: The hemodynamic of anaesthetized dogs were observed after intravenous injection of CVB-D at doses of 0.1, 0.2, 0.4 mg/kg. RESULTS: CVB-D of 0.2 and 0.4 mg/kg could decrease HR, TPVR and increase CBF. In addition, CVB-D of 0.4 mg/kg could increase SAP and SV. Yet MAP and CO of dogs showed no remarkable changes with the treatment of CVB-D. CONCLUSION: CVB-D has effect of improving cardiac function, which may be the mechanism of anti-myocardial ischemia effect of CVB-D.

[Vasorelaxation effects of homoisoflavonoids from Caesalpinia sappan in rat thoracic aortic rings].

OBJECTIVE: To identify and elucidate the vasorelaxant activity of homoisoflavonoids, the main chemical components from Lignum Sappan (the stems of Caesalpinia sappan), in isolated rat thoracic aortic rings pre-contracted with phenylephrine (PE, 1 micromol x L(-1)) and KCl (60 mmol x L(-1)). METHOD: The tension of rat thoracic aorta rings was used to evaluated the vasorelaxant activities of four homoisoflavonoids, brazlin (1), (E)-3-(3,4-dihydroxybenzylidene)-7-hydroxychroman-4-one (2), sappanone B (3), 3-deoxysappanone B (4). RESULT: Cumulative addition of homoisoflavonoids (2, 3 and 4) (50-1000 micromol x L(-1)) exhibited an acute relaxation either in endothelium-intact or endothelium-denuded rings in a concentration-dependent manner. However, this relaxation was significantly inhibited in endothelium-denuded condition and in the presence of endothelial nitric oxide synthase (eNOS) inhibitor, N(W)-nitro-L-arginine methyl ester (L-NNA, 100 micromol x L(-1)), and a soluble guanylate cylcase (sGC) inhibitor, methylene blue (MB, 10 micromol x L(-1)) when addition of variation homoisoflavonoids brazlin (1) (50-1000 micromol x L(-1)). CONCLUSION: These results indicate that normo-homoisoflavonoids (2, 3 and 4) from Caesalpinia sappan mediates endothelium-independent vasodilator action in rat thoracic aortic rings, while the variation homoisoflavonoids brazlin elicits endothelium-dependent relaxation might via nitric oxide (NO)-cGMP pathway. This research could explain the pharmacological activities of homoisoflavonoids to a certain degree.

[Research progress on pharmacological activities of echinacoside].

The paper reviews the recent developments in pharmacological activities of echinacoside (ECH). ECH is a phenylethanoid glycoside isolated and purified from the stems of Cistanche salsa, a parasitic plant native to northwest China, which is used as a traditional Chinese herbal medicine. During past years, ECH had been shown to possess powerful ability of anti-oxidant and free radical scavenging properties. It has been evident that ECH had neuroprotective effects and prevent liver injuries. Besides, ECH has affect in anti-inflammatory, antitumor, antiaging, immunoregulation, improving learning memory and so on. Therefore, ECH should be considered for further study and develop as a novel drug.

The protective effect of Zizyphus jujube fruit on carbon tetrachloride-induced hepatic injury in mice by anti-oxidative activities.

AIM OF THE STUDY: The study was aimed to investigate the protective effect against hepatic injury induced by CCl(4) for the ethanolic extract of FZJ. MATERIALS AND METHODS: The alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were detected as biomarker in blood of hepatic injury. Product of lipid peroxidation (MDA), activities of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px), and reduced glutathione (GSH) contents were evaluated for oxidative stress in hepatic injury. Moreover, histopathological observation was assayed at the degree of hepatic injury. RESULTS: After administrated the FZJ, the dose of 200mg/kg significantly decreased ALT and AST, and attenuated histopathology of hepatic injury, and ameliorated the oxidative stress in hepatic tissue. Partly assayed indexes were ameliorated after administrated FZJ at the dose of 100mg/kg. CONCLUSION: These results indicated that hepatic protective effects of FZJ were very relevant to modulate the oxidative stress in hepatic injury.

Echinacoside elicits endothelium-dependent relaxation in rat aortic rings via an NO-cGMP pathway.

The aim of this study was to identify and elucidate the vasorelaxant activity of echinacoside, a phenylethanoid glycoside isolated from the medicinal herb Cistanche tubulosa, and its possible underlying mechanism on isolated rat thoracic aortic rings pre-contracted with phenylephrine (PE, 1 microM) and KCl (60 mM). Echinacoside (30-300 microM) exhibited an acute relaxation in endothelium-intact rings in a concentration-dependent manner, while this relaxation was significantly inhibited in endothelium-denuded condition and in the presence of the endothelial nitric oxide synthase (eNOS) inhibitor, N(W)-nitro-L-arginine methyl ester (L-NNA, 100 microM), an unselective soluble guanylate cyclase blocker, methylene blue (10 microM), the selective sGC inhibitor 1 H-[1, 2, 4]oxadiazolo[4,3- A]quinoxalin-1-one (ODQ, 1 microM); in addition, atropine (1 microM), a selective muscarinic receptor antagonist, partially affected the relaxation. However, the cyclooxygenase inhibitor indomethacin (5 microM) had no influence on the action. Echinacoside enhanced the cyclic guanosine monophosphate (cGMP) production in aortic rings contracted with PE. These results indicate for the first time that echinacoside mediates the endothelium-dependent vasodilator action in rat thoracic aortic rings through nitric oxide (NO)-cGMP pathway.

Preventive effects of quercetin against benzo[a]pyrene-induced DNA damages and pulmonary precancerous pathologic changes in mice.

The aim of this study was to investigate the preventive effects of quercetin against benzo[a]pyrene-induced blood lymphocyte DNA damages and pulmonary precancerous pathologic changes in mice, and to reveal the potential mechanism behind these effects. In this study, mice in quercetin-treated groups were given quercetin for 90 days. After one week of treatment, mice in the quercetin-treated groups and the positive control group received a single intraperitoneal dose of benzo[a]pyrene (100 mg/kg body weight). The results of single cell gel electrophoresis assay showed that the average lengths of the comet cell tail and DNA damage in the peripheral blood lymphocytes of mice induced by benzo[a]pyrene decreased significantly as a result of quercetin treatment dose-dependently. Light microscopic examination showed that the degrees of pulmonary precancerous pathologic changes in the quercetin-treated groups decreased significantly compared with those in the positive control group. Meanwhile, the cytochrome P4501A1-linked 7-ethoxyresorufin O-dealkylase activities in lung microsomes of mice decreased as the dose of quercetin increased. The results of this in vivo study revealed that quercetin had a significant preventive effect on benzo[a]pyrene-induced DNA damage, and had a potential chemopreventive effect on the carcinogenesis of lung cancer induced by benzo[a]pyrene. The mechanism of these effects of quercetin could be related to the inhibition of cytochrome P4501A1 activity.