Jiehong Yang

Synergistic protective effect of astragaloside IV–tetramethylpyrazine against cerebral ischemic-reperfusion injury induced by transient focal ischemia

ETHNOPHARMACOLOGICAL RELEVANCE Astragaloside IV and tetramethylpyrazine have been extensively used in the cardio-cerbrovascular diseases of medicine as a chief ingredient of glycoside or alkaloid formulations for the treatment of stroke and myocardial ischemia diseases. AIM OF THE STUDY To investigate the effects of astragaloside IV (ASG IV) and tetramethylpyrazine (TMPZ) on cerebral ischemia-reperfusion (IR) injury model in rat model. MATERIALS AND METHODS Rats were randomly divided into the following five groups: sham group, IR group and treatment group including ASG IV, ASG IV-TMPZ and nimodipine treatment. The therapeutic effect was evaluated by micro-positron emission tomography (Micro-PET) using (18)F-fluoro-2-deoxy-d-glucose. The neurological examination, infarct volume and the levels of oxidative stress- and cell apoptosis-related molecules were assessed. RESULTS Micro-PET imaging showed that glucose metabolism in the right hippocampus was significantly decreased in the IR group compared to the sham group (P<0.01). ASG IV and ASG IV-TMPZ treatments reversed the decreased glucose metabolism in the model group (P<0.05 and P<0.01, respectively). IR induced the increase of Caspase-3 mRNA levels, MDA content and iNOS activity, but it caused the decrease of SOD activity and Bcl-2 expression compared the sham group (P<0.01). ASG IV-TMPZ and ASG IV reversed the IR-induced changes of these parameters, i.e. the down regulation of Caspase-3 mRNA, MDA content and iNOS activity, and the up regulation of SOD activity and Bcl-2 expression (P<0.05). CONCLUSION This study showed that ASG IV-TMPZ played a pivotal synergistic protective role against focal cerebral ischemic reperfusion damage in a rat experimental model.

Lipid-lowering effects of Danhong injection on hyperlipidemia rats.

ETHNOPHARMACOLOGICAL RELEVANCE Danhong injection (DHI), a Chinese medical product extracted from Radix et Rhizoma Salviae Miltiorrhizae (Salvia miltiorrhiza Bge., Labiatae, Danshen in Chinese) and Flos Carthami (Carthamus tinctorius L., Compositae, Honghua in Chinese), has been reported to have anti-inflammatory, anti-oxidative and anti-fibrinolytic properties and is used extensively for the clinical treatment of cardiovascular disease in clinic. This study aimed to investigate the preventive and therapeutic effects of DHI on hyperlipidemia. MATERIALS AND METHODS Forty-eight adult male Sprague-Dawley rats were randomly divided into four groups: normal control (NC), model control (MC) and DHI-treated at doses of 1.0mL/kg and 2.0mL/kg. The effects of DHI on serum triglyceride (TG), total cholesterol (TC), glucose, high density lipoprotein cholesterol (HDL-C) and low density lipoprotein cholesterol (LDL-C) were evaluated and insulin was determined by enzyme-linked immunosorbent assay (ELISA). Moreover, the expression of acetyl-CoA carboxylase 1 (ACC1), fatty acid synthase (FAS), carnitine palmitoyl transferase 1 (CPT1), hydroxymethylglutaryl-CoA reductase (HMGR) and peroxisome proliferator-activated receptor alpha (PPAR-α) in liver were determined by real-time PCR. RESULTS Compared with the MC group, rats treated with DHI had significantly reduced TG, TC, LDL-C and arteriosclerosis index (AI). Expression of FAS and HMGR mRNA was significantly reduced, whereas the CPT1 and PPAR-α were significantly increased. CONCLUSION DHI treatment was accompanied by significantly increased lipolysis in the liver and decreased fatty acid synthesis. The insights gained from this study will improve both understanding of the mechanisms involved in the effect of DHI on hyperlipidemia and the pharmacological rationale for the use of DHI in diseases caused by lipid metabolic disorders.

Evaluation of the hepatoprotective and antioxidant activities of Rubus parvifolius L.

The hepatoprotective and antioxidant activities of the n-butanol extract of Rubus parvifolius L. (RPL), a widely used medicinal plant, were evaluated. Results demonstrated that RPL extract possessed pronounced hepatoprotective effects against carbon tetrachloride (CCl4)-induced hepatic injury in mice, which was at least partially attributed to its strong antioxidant capacity. Treatment with RPL extract markedly attenuated the increases in serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels caused by CCl4 intoxication. It also significantly prevented the decrease in superoxide dismutase (SOD) activity and the increase in malondialdehyde (MDA) content of liver tissue. Meanwhile, histopathological changes of hepatic damage were also remarkably ameliorated. Phytochemical analysis based on high-performance liquid chromatography/tandem mass spectrometry (HPLC-MS/MS) revealed the presence of various phenolic compounds, including caffeic acid conjugates, ellagic acid glycosides, and flavonol glycosides, which might be responsible for the hepatoprotective and antioxidant activities of RPL.

PET Demonstrates Functional Recovery after Treatment by Danhong Injection in a Rat Model of Cerebral Ischemic-Reperfusion Injury

This study aimed to investigate neuroprotection of Danhong injection (DHI) in a rat model of cerebral ischemia using 18F-fluorodeoxyglucose positron emission tomography (18F-FDG-PET). Method. Rats were divided into 5 groups: sham group, ischemia-reperfusion untreated (IRU) group, DHI-1 group (DHI 1 mL/kg/d), DHI-2 group (DHI 2 mL/kg/d), and DHI-4 group (DHI 4 mL/kg/d). AII the treated groups were intraperitoneally injected with DHI daily for 14 days. The therapeutic effects in terms of cerebral infarct volume, neurological function, and cerebral glucose metabolism were evaluated. Expression of TNF-α and IL-1β was detected with enzyme-linked immunosorbent assay (ELISA). Levels of mature neuronal marker (NeuN), glial marker (GFAP), vascular density factor (vWF), and glucose transporter 1 (GLUT1) were assessed by immunohistochemistry. Results. Compared with the IRU group, rats treated with DHI showed dose dependent reductions in cerebral infarct volume and levels of proinflammatory cytokines, improvement of neurological function, and recovery of cerebral glucose metabolism. Meanwhile, the significantly increased numbers of neurons, gliocytes, and vessels and the recovery of glucose utilization were found in the peri-infarct region after DHI treatment using immunohistochemical analysis. Conclusion. This study demonstrated the metabolic recovery after DHI treatment by micro-PET imaging with 18F-FDG and the neuroprotective effects of DHI in a rat model of cerebral ischemic-reperfusion injury.

Neuroprotective effect of parthenocissin A, a natural antioxidant and free radical scavenger, in focal cerebral ischemia of rats.

Neuroprotective effects of parthenocissin A (PA), a novel antioxidant and free radical scavenger, were studied in a transient middle cerebral artery (MCA) occlusion model in rats for the first time. The animals were treated intraperitoneally with PA at 2.5, 5 or 10 mg/kg, for both 30 min before MCA occlusion and 6 h after reperfusion. The MCA was occluded for 1 h in anesthetized Sprague‐Dawley rats. Compared with vehicle‐treated controls, MCA occluded animals treated with PA showed dose‐dependent reductions in brain infarction size with improved neurological and motor outcome. Biomedical assay showed that the PA treatment suppressed lipid peroxidation and restored superoxide dismutase (SOD) activity in brain tissue. In addition, the ischemia/reperfusion (I/R) induced elevation of nitric oxide (NO) production and nitric oxide synthase (NOS) activity in brain tissue was also inhibited. Thus, PA demonstrated a neuroprotective effect in the I/R model and the beneficial effects of the compound may result from the reduction of oxidative stress and the inhibition of NO production induced by I/R. The neuroprotective effects of PA have highlighted the potential use of stilbene oligomers in stroke therapy. Copyright

Effect of ligustrazine on levels of amino acid neurotransmitters in rat striatum after cerebral ischemia-reperfusion injury

This study aimed to evaluate the effect of ligustrazine on levels of amino acid transmitters in the extracellular fluid of striatum following cerebral ischemia/reperfusion (I/R) in male Sprague-Dawley rats. A microdialysis cannula guide was implanted into the right striatum. After recovery, animals underwent a sham operation or middle cerebral artery occlusion (MCAO). Those that developed cerebral ischemia after MCAO were randomized to receive propylene glycol salt water and ligustrazine respectively. Striatal fluid samples were collected from all animals at 15-min intervals after treatment and were subjected to HPLC analysis of aspartic acid, glutamic acid, taurine, and γ-amino butyric acid. Upon the last sample collection, animals were sacrificed and brain tissue specimens were collected for triphenyltetrazolium chloride staining and NeuN staining. Compared with the sham operation, MCAO induced significant neurological deficits and increased striatal concentrations of the four neurotransmitters assessed in a time-dependent manner (P < 0.01). Ligustrazine effectively attenuated the detrimental effects of MCAO on the brain. These observations suggest that ligustrazine as a novel cerebral infarction-protective agent may have potential clinical implications for I/R-related brain damage.

Molecular cloning and characterization of a cDNA encoding cycloartenol synthase from Fritillaria thunbergii Miq.

Fritillaria thunbergii Miq., known as the bulbous plants of the genus fritillaria , produces a large amount of sterols. Homology based polymerase chain reactions (PCRs) with degenerate primers designed from the conserved sequences among the known cycloartenol synthase (CAS) resulted in cloning of a CAS from the young leaves of F. thunbergii Miq . A putative cycloartenol synthase cDNA ( FtCAS ) consists of a 2271 bp open reading frame, which encodes for 756 amino acids. The deduced amino acid sequence shows 82% homology to cycloartenol synthases from Dioscorea zingiberensis . Heterologous expression of the FtCAS in the methylotrophic yeast, Pichia pastoris , resulted in production of cycloartenol. Our results indicate that FtCA S encode cycloartenol synthase.

Effects of Danhong Injection on platelet aggregation in hyperlipidemia rats

ETHNOPHARMACOLOGICAL RELEVANCE Danhong Injection (DHI), a Chinese medical product extracted from Radix et Rhizoma Salviae Miltiorrhizae (Salvia miltiorrhiza Bge., Labiatae, Danshen in Chinese) and Flos Carthami (Carthamus tinctorius L., Compositae, Honghua in Chinese), has been reported to have effects on inflammatory, anti-fibrinolytic properties, antithrombotic and decrease blood-lipid. It is extensively used for the clinical treatment of cardiovascular disease. This study aimed to investigate the effects of DHI on blood-lipid levels and platelet aggregation rate in hyperlipidemia rats. MATERIALS AND METHODS Rats were randomly divided into 6 groups: normal control (NC), model control (MC), DHI-treated control at doses of 1.0mL/kg, 2.0mL/kg, 4.0mL/kg, respectively, and Simvastatin positive control at dose of 2.0mg/kg. All DHI treated groups were intraperitoneally injected for 7 days. The effects of DHI on serum triglyceride (TG), total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C) were evaluated. And platelet activating factor (PAF), platelet membrane glycoprotein IIb/IIIa (GP IIb/IIIa) and 6-keto-prostaglandin F1а (6-K-PGF1а) were determined by enzyme-linked immunosorbent assay (ELISA). Moreover, the expression of prostaglandin I-2 (PGI2), prostaglandin E-2 (PGE2) and thromboxane A2 (TXA2) in liver was determined by real-time PCR. RESULTS Compared with the MC group, the rats treated with DHI had significantly reduced TC, TG, LDL-C, FIB, GP IIb/IIIa and platelet aggregation. Meanwhile, the thrombin time (TT), activated partial thrombin time (APTT), prothrombin time (PT), 6-K-PGF1а was significantly increased. Expression of PGI2 and PGE2 mRNA was significantly increased, whereas the TXA2 was significantly reduced. CONCLUSIONS This study demonstrated that the blood lipid and platelet aggregation has a regulatory effect after DHI treatment. The insights gained from this study will improve understanding of the mechanisms involved in the effect of DHI on hyperlipidemia and the pharmacological rationale for the use of DHI in diseases caused by formation of thrombosis and lipid metabolic disorders.

Protective effect of Danhong Injection combined with Naoxintong Capsule on cerebral ischemia-reperfusion injury in rats

ETHNOPHARMACOLOGICAL RELEVANCE Danhong Injection (DHI) and Naoxintong Capsule (NXT) are renowned traditional Chinese medicine in China. The drug combination of DHI and NXT is frequently applied for the treatment of cardiovascular and cerebrovascular diseases in clinic. However, there had been no pharmacological experiment studies of interaction between DHI and NXT. Due to the drug interactions, exploring their interaction profile is of great importance. MATERIAL AND METHODS In this study, focal cerebral I/R injury in adult male Sprague-Dawley rats were induced by transient middle cerebral artery occlusion (tMCAO) for 1h followed by reperfusion. Rats were divided into 5 groups: sham group, ischemia reperfusion untreated group (IRU), DHI group (DHI 10mL/kg/d), NXT group (NXT 0.5g/kg/d), DHI plus NXT group (DHI-NXT, DHI 10mL/kg/d plus NXT 0.5g/kg/d). All drug-treated groups were respectively successive administrated for 7 days after ischemia/ reperfusion (I/R) injury. The effects on rat neurological function were estimated by neurological defect scores. Brain infarct volumes were determined based on 2, 3, 5-triphenyltetrazolium chloride (TTC) staining. Pathological changes in brain tissues were observed using hematoxylin and eosin (H&E) staining and transmission electron microscope (TEM). Levels of nitric oxide (NO), granulocyte colony-stimulating factor (G-CSF) and granulocyte macrophage colony-stimulating factor (GM-CSF) in serum were determined with enzyme-linked immunosorbent assay (ELISA). Immunohisto-chemistry and Western blot were used to detect the expressions of basic fibroblast growth factor (bFGF), von Willebrand factor-microvessel vascular density (vWF-MVD), vascular endothelial cell growth factor (VEGF), transforming growth factor-β1 (TGF-β1), angiogenin-1 (Ang-1), angiogenin-2 (Ang-2) and platelet derived growth factor (PDGF) at day 7 after ischemia/reperfusion (I/R) injury. RESULTS Compared with IRU group and mono-therapy group (DHI group or NXT group), Danhong Injection combined with Naoxintong Capsule (DHI-NXT) group significantly ameliorated neurological deficits scores, infarct volume and pathological change, significantly decreased the overexpression of NO and the level of Ang-1, significantly increased the expressions of VEGF, Ang-2, G-CSF, GM-CSF, bFGF, PDGF, vWF, TGF-β1. CONCLUSION The protective benefits on rat brain against I/R injury were clearly produced when DHI and NXT were used in combination, which provided rational guidance for clinical combined application of DHI and NXT, and this protection maybe associated with the up-regulation expressions of the related chemokines and growth factors of angiogenesis.

Effects of Active Components of Fuzi and Gancao Compatibility on Bax, Bcl-2, and Caspase-3 in Chronic Heart Failure Rats

Hypaconitine (HA) and glycyrrhetinic acid (GA) are active components of Fuzi (Aconitum carmichaelii) and Gancao (Glycyrrhiza uralensis Fisch); they have been used in compatibility for chronic heart failure (CHF) from ancient times. The purpose of the present research was to explore whether apoptosis pathways were related with the protective effects of HA + GA against CHF rats or not. The rats were progressed with transverse-aortic constriction (TAC) operation for 4 weeks to build the CHF state, and then the Digoxin (1 mg/kg), HA (2.07 mg/kg), GA (25 mg/kg), and HA (2.07 mg/kg) + GA (25 mg/kg) were orally administrated to rats for 1 week. The levels of BNP and cTnI in the plasma were decreased in the HA + GA group, and the heart/body weight ratio (H/B) and left ventricular (LV) parameters of transthoracic echocardiography were also declined; moreover, the expressions of Bax, Bcl-2, and caspase-3 were all improved in the HA + GA group than other groups in the immunohistochemistry and western blot methods. In general, the data suggested that Fuzi and Gancao compatibility could protect the CHF rats from apoptosis, which provided a strong evidence for further searching for mechanisms of them.