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Elevated levels of plasma homocysteine (Hcy) causes severe cardiac dysfunction, which is closely associated with oxidative stress. Emodin, a naturally occurring anthraquinone derivative, has been shown to exert antioxidant and anti-apoptosis activities. However, whether emodin could protect against Hcy-induced cardiac dysfunction remains unknown. The current study aimed to investigate the effects of emodin on the Hcy-induced cardiac dysfunction and its molecular mechanisms. Rats were fed a methionine diet to establish the animal model of hyperhomocysteinemia (HHcy). H9C2 cells were incubated with Hcy to induce a cell model of Hcy-injured cardiomyocytes. ELISA, HE staining, carotid artery and left ventricular cannulation, MTT, fluorescence staining, flow cytometry and western blotting were used in this study. Emodin significantly alleviated the structural damage of the myocardium and cardiac dysfunction from HHcy rats. Emodin prevented apoptosis and the collapse of MMP in the Hcy-treated H9C2 cells in vitro. Further, emodin reversed the Hcy-induced apoptosis-related biochemical changes including decreased Bcl-2/Bax protein ratio, and increased protein expression of Caspase-9/3. Moreover, emodin suppressed oxidative stress in Hcy-treated H9C2 cells. Mechanistically, emodin significantly inhibited the Hcy-activated MAPK by reducing ROS generation in H9C2 cells. Furthermore, emodin upregulated NO production by promoting the protein phosphorylation of Akt and eNOS in injured cells. The present study shows that emodin protects against Hcy-induced cardiac dysfunction by inhibiting oxidative stress via MAPK and Akt/eNOS/NO signaling pathways.

Cardiac hypertrophy is a common myocardial structural abnormality which may cause heart failure. Many studies have shown that cardiac hypertrophy can be induced by hyperthyroidism. Ligand-gated potassium channels have been reported to be involved in various biological processes in the cardiovascular system, such as GPCR coupled K(ACh) and metabolism sensor K(ATP) channel. It is unclear whether the gene expression of K(ACh) and K(ATP) was altered in hyperthyroid rabbit atria. We aimed to investigate the expression of K(ACh) and K(ATP) genes in rabbit atria in our experimental model. We established an effective hyperthyroidism-induced cardiac hypertrophy animal model through an injection of T4. H&E staining and RT-PCR were used to observe the histomorphological damages and alteration of gene expression. The results showed that the heart weight, heart rate significantly increased in T4-treated rabbits. The systolic pressure increased from 115.60 mmHg to 152.6 mmHg in T4-treated rabbits. The expression of K(ACh) and K(ATP) genes was decreased in the atria of hyperthyroidism-induced cardiac hypertrophied rabbits. These findings indicated that the decreased gene expression of K(ACh) and K(ATP) may be related to hyperthyroidism-induced cardiac hypertrophy and atrial fibrillation.

Homocysteine (Hcy) induced vascular endothelial dysfunction is known to be closely associated with oxidative stress and impaired NO system. 1,8-Dihydroxy-3-methoxy-6-methylanthracene-9,10-dione (physcion) has been known to has antioxidative and anti-inflammatory properties.The purpose of the present study was to define the protective effect of physcion on Hcy-induced endothelial dysfunction and its mechanisms involved.Hyperhomocysteinemia (HHcy) rat model was induced by feeding 3% methionine. A rat thoracic aortic ring model was used to investigate the effects of physcion on Hcy-induced impairment of endothelium-dependent relaxation. Two doses, low (L, 30 mg/kg/day) and high (H, 50 mg/kg/day) of physcion were used in the present study. To construct Hcy-injured human umbilical vein endothelial cells (HUVECs) model, the cells treated with 3 mM Hcy. The effects of physcion on Hcy-induced HUVECs cytotoxicity and apoptosis were studied using MTT and flow cytometry. Confocal analysis was used to determine the levels of intracellular CaIn the HHcy rat model, plasma levels of Hcy and malondialdehyde (MDA) were elevated (20.45 ± 2.42 vs. 4.67 ± 1.94 μM, 9.42 ± 0.48 vs. 3.47 ± 0.59 nM, p0.001 for both), whereas superoxide dismutase (SOD) and nitric oxide (NO) levels were decreased (77.11 ± 4.78 vs. 115.02 ± 5.63 U/ml, 44.51 ± 4.45 vs. 64.18 ± 5.34 μM, p0.001 and p0.01, respectively). However, treatment with physcion significantly reversed these changes (11.82 ± 2.02 vs. 20.45 ± 2.42 μM, 5.97 ± 0.72 vs. 9.42 ± 0.48 nM, 108.75 ± 5.65 vs. 77.11 ± 4.78 U/ml, 58.14 ± 6.02 vs. 44.51 ± 4.45 μM, p0.01 for all). Physcion also prevented Hcy-induced impairment of endothelium-dependent relaxation in HHcy rats (1.56 ± 0.06 vs. 15.44 ± 2.53 nM ECPhyscion prevents Hcy-induced endothelial dysfunction by activating Ca

Objective To define the effects of Xanthoceras sorbifolia (EXS) on vascular inflammation and the mechanisms in endothelial cells. Methods Vascular protective effects of an ethanol extract of seeds from EXS (1-50 μg/mL) against tumor necrosis factor-α (TNF-α)-induced vascular inflammation were examined in human umbilical vein endothelial cells (HUVECs). Results EXS significantly decreased TNF-α-induced expression of cell adhesion molecules, such as intracellular adhesion molecule-1, vascular cell adhesion molecule-1, and endothelial cell selectin, in a dose-dependent manner. Pre-treatment with EXS significantly inhibited translocation and transcriptional activity of nuclear factor-κB (NF-κB) increased by TNF-α. EXS also significantly inhibited formation of intracellular reactive oxygen species (ROS). Moreover, the vascular protective effects of EXS were linked to up-regulation of heme oxygenase-1 (HO-1) and nuclear factor E2-related factor-2 (Nrf-2) expression. EXS-induced HO-1 expression was significantly decreased in SnPP (HO-1 inhibitor)- and HO-1 siRNA-treated cells, whereas an increase was found in cobalt protoporphyrin IX (CoPP) (HO-1 inducer)-treated cells. In addition, pretreatment with EXS increased HO-1 and Nrf-2 expression under TNF-α stimulation with or without N-acetyl-L-cysteine. Furthermore, the inhibitory effects of EXS on TNF-α-induced vascular inflammation were partially reversed in SnPP- and of HO-1 siRNA-treated cells but increased by CoPP. Conclusion These results suggest that EXS may have important implications for prevention of vascular complications associated with vascular inflammation by inhibition of the NF-¦EB/ROS pathway and activation of the Nrf-2/HO-1 pathway.

Background Homocysteine (Hcy) induced vascular endothelial dysfunction is known to be closely associated with oxidative stress and impaired NO system. 1,8-Dihydroxy-3-methoxy-6-methylanthracene-9,10-dione (physcion) has been known to has antioxidative and anti-inflammatory properties. Purpose The purpose of the present study was to define the protective effect of physcion on Hcy-induced endothelial dysfunction and its mechanisms involved. Study Design and Methods Hyperhomocysteinemia (HHcy) rat model was induced by feeding 3% methionine. A rat thoracic aortic ring model was used to investigate the effects of physcion on Hcy-induced impairment of endothelium-dependent relaxation. Two doses, low (L, 30 mg/kg/day) and high (H, 50 mg/kg/day) of physcion were used in the present study. To construct Hcy-injured human umbilical vein endothelial cells (HUVECs) model, the cells treated with 3 mM Hcy. The effects of physcion on Hcy-induced HUVECs cytotoxicity and apoptosis were studied using MTT and flow cytometry. Confocal analysis was used to determine the levels of intracellular Ca2+. The levels of protein expression of the apoptosis-related markers Bcl-2, Bax, caspase-9/3, and Akt and endothelial nitric oxide synthase (eNOS) were evaluated by western blot. Results In the HHcy rat model, plasma levels of Hcy and malondialdehyde (MDA) were elevated (20.45 ± 2.42 vs. 4.67 ± 1.94 μM, 9.42 ± 0.48 vs. 3.47 ± 0.59 nM, p Conclusion Physcion prevents Hcy-induced endothelial dysfunction by activating Ca2+- and Akt-eNOS-NO signaling pathways. This study provides the first evidence that physcion might be a candidate agent for the prevention of cardiovascular disease induced by Hcy.

Ursolic acid has recently been reported to increase both atrial natriuretic peptide (ANP) secretion and mechanical dynamics in rabbit atria.The present study was designed to clarify the regulatory effects of ursolic acid on the β-adrenergic or muscarinic receptor-mediated changes in ANP secretory and contractile function allowing measurement of atrial dynamics such as pulse pressure, stroke volume, and cAMP efflux in isolated perfused beating rabbit atria.Pretreatment with ursolic acid significantly attenuated the isoproterenol (β-adrenergic agonist)-induced decrease in ANP secretion and increases in cAMP levels and atrial dynamics. Interestingly, ursolic acid concentration-dependently accentuated the acetylcholine-induced increase in ANP secretion and decrease in pulse pressure in the presence of isoproterenol (p0.001). These findings indicate that acetylcholine-induced increase in ANP secretion is potentiated by ursolic acid; furthermore, acetylcholine-induced decrease in atrial dynamics is also potentiated by ursolic acid, suggesting that ursolic acid regulates muscarinic receptor-mediated secretory and contractile responses in perfused beating rabbit atria.This implicates for the beneficial effects of ursolic acid in the regulation of cardiovascular and body fluid homeostasis.

Homocysteine (Hcy) is an independent risk factor in the development of cardiovascular diseases (CVD). Hyperhomocysteinemia (HHcy), induces the injury of vascular endothelial cells via oxidative stress. Oxymatrine (OMT), one of the main components of Sophora flavescens, has displayed anti-inflammatory, anti-oxidant and anti-apoptotic activity. However, the effect of OMT on the Hcy-induced endothelial injury is not clearly defined yet. The aim of this study was to determine the protective effect of OMT on the Hcy-induced endothelial injury and its mechanisms involved. Human umbilical vein endothelial cells (HUVECs) were cultured in vitro. Methyl thiazolyl tetrazolium assay (MTT), fluorescence staining, flow cytometry and western blotting were used in this study. OMT prevented the Hcy-induced toxicity and apoptosis in HUVECs. Moreover, OMT suppressed Hcy-induced increases in reactive oxygen species, lactate dehydrogenase, malondialdehyde levels and increased superoxide dismutase levels. OMT reversed the Hcy-induced decrease in the protein expression of nuclear factor erythroid-2-related factor 2 (Nrf2). In addition, OMT reversed the Hcy-induced apoptosis related biochemical changes such as decreased mitochondrial membrane potential and Bcl-2/Bax protein ratio, and increased protein expression of caspase-9 and caspase-3. Furthermore, OMT elevated the phosphorylation levels of Akt and eNOS, and the formation of nitric oxide (NO) in injured cells. These results suggest that OMT prevents Hcy-induced endothelial injury by regulating mitochondrial-dependent apoptosis and Akt-eNOS-NO signaling pathways concomitantly with accentuation of Nrf2 expression.

Ethnopharmacological relevance Radix Paeoniae Rubra (RPR) is an important traditional Chinese medicine (TCM) commonly used in clinic for a long history in China. RPR is the radix of either Paeonia lactiflora Pall. or Paeonia veitchii Lynch. RPR has a wide variety of pharmacological actions such as anti-thrombus, anti-coagulation, and anti-atherosclerotic properties, protecting heart and liver. However, the mechanisms involved are to be defined. Aim of the study The aim of the present study was to define the effect of Paeonia lactiflora Pall. extracts on vascular tension and responsible mechanisms in rat thoracic aortic rings. Materials and methods Ethanol extract of Paeonia lactiflora Pall. (EPL) was examined for their vascular relaxant effects in isolated phenylephrine-precontracted rat thoracic aorta. Results EPL induced relaxation of the phenylephrine-precontracted aortic rings in a concentration-dependent manner. Vascular relaxation induced by EPL was significantly inhibited by removal of the endothelium or pretreatment of the rings with N G -nitro- l -arginine methylester ( l -NAME) or 1 H -[1,2,4]-oxadiazolo-[4,3- α ]-quinoxalin-1-one (ODQ). Extracellular Ca 2+ depletion or diltiazem significantly attenuated EPL-induced vasorelaxation. Modulators of the store-operated Ca 2+ entry (SOCE), thapsigargin, 2-aminoethyl diphenylborinate and Gd 3+ , and an inhibitor of Akt, wortmannin, markedly attenuated the EPL-induced vasorelaxation. Further, the EPL-induced vasorelaxation was significantly attenuated by pretreatment with tetraethylammonium, a non-selective K Ca channels blocker, or glibenclamide, an ATP-sensitive K + channels inhibitor, respectively. Inhibition of cyclooxygenases with indomethacin, and adrenergic and muscarinic receptors blockade had no effects on the EPL-induced vasorelaxation. Conclusions The present study suggests that EPL relaxes vascular smooth muscle via endothelium-dependent and Akt- and SOCE-eNOS-cGMP-mediated pathways through activation of both K Ca and K ATP channels and inhibition of L-type Ca 2+ channels.

Aim of the study The aim of the present study was to define the effect of Xanthoceras sorbifolia extracts (XS) on vascular tension and responsible mechanisms in rat thoracic aortic rings. Materials and methods Ethanol extract of the leaves of XS (EXS) was examined for their vascular relaxant effects in isolated phenylephrine-precontracted rat thoracic aorta. Results EXS (0.1–100 μg/ml) induced relaxation of the phenylephrine-precontracted aortic rings in a concentration-dependent manner. Endothelium-denudation abolished EXS-induced vasorelaxation. Pretreatment of the endothelium-intact aortic rings with N G -nitro- l -arginine methylester ( l -NAME) and 1H-[1,2,4]-oxadiazolo-[4,3-α]-quinoxalin-1-one (ODQ) inhibited EXS-induced vasorelaxation. Inhibition of Ca 2+ entry via l -type Ca 2+ channels failed to block the EXS-induced vasorelaxation. Extracellular Ca 2+ depletion significantly attenuated EXS-induced vasorelaxation. Modulators of the store-operated Ca 2+ entry (SOCE), thapsigargin, 2-aminoethyl diphenylborinate (2-APB) and Gd 3+ , and an inhibitor of Akt, wortmannin, markedly attenuated the EXS-induced vasorelaxation. EXS increased cGMP levels of the aortic rings in a concentration-dependent manner and the effect was blocked by l -NAME, ODQ, thapsigargin, Gd 3+ , 2-APB, and wortmannin. Further, EXS-induced vasorelaxation was significantly attenuated by tetraethylammonium, a non-selective K ca channels blocker, but not by glibenclamide, an ATP-sensitive K + channels inhibitor. Inhibition of cyclooxygenase with indomethacin, and adrenergic and muscarinic receptors blockade had no effects on EXS-induced vasorelaxation. Conclusions The present study suggests that EXS relaxes vascular smooth muscle via endothelium-dependent NO-cGMP signaling through activation of the Akt- and SOCE-eNOS-sGC pathways, which may, at least in part, be related to the function of K + channels.

The genetic diversity of 279 indivdiuals from 10 populations in Shandong Province was investigated using inter-simple sequence repeat (ISSR) markers. As a result, 116 bands were amplified by 10 informative and reliable primers, of which 101 were polymorphic loci. A relatively high level of genetic diversity was revealed: PPL = 87.07, He = 0.2697, H0 = 0.3999 (at the species level); PPL = 64.58, He = 0.2004, H0 = 0.3010 (at the population level). A higher level of genetic differentiation was detected among populations with Nei's G(ST) analysis and the analysis of molecular variance (AMOVA; G(ST) = 0.2414, F(ST) = 0.2224). Habitat fragmentation and gene flow may result in genetic differentiation. UPGMA cluster analysis indicated that the four populations from Linshu, Junan, Tancheng and Feixian grouped together, whereas Laiyang populations clustered in an isolated clade. The results showed that a mixed mating system was possibly the main factor influencing the genetic structure of this species. These results, combined with other information about Castanea mollissima, may provide a valuable basis for proposing conservation strategies.

This study was carried out to investigate the influence of medium composition for in vitro mass propagation of Lycoris squamigera Max. After the disks of short stems, segments of leaf within bulb and scale were cultured on MS basal medium supplemented with various plant growth regulators, they were examined for the extent of callus formation, shoot and root regeneration. In the culture of stem disks, adventitious shoots were regenerated from the basal tissue of bulb scales, and combined medium of 1.0 mg/L 2,4-D or NAA＋2.0 mg/L BA or kinetin showed the the best response and 4∼6 shoots per explant formed. In the culture of leaf segments within bulbs, both MS medium supplemented with 1.0 mg/L NAA＋2.0 mg/L TDZ and with 1.0 mg/L 2,4-D＋1.0∼2.0 mg/L BA were produced callus profusely on the base of leaf tissue and 3∼6 shoots were regenerated per explant. In the scale segments culture, calli were produced on the basal tissue on medium with 1.0 mg/L 2,4-D＋1.0∼2.0 mg/L BA. The best result were shown on MS medium with 1.0 mg/L NAA＋2.0 mg/L TDZ, and 1.0 mg/L 2,4-D＋1.0∼2.0 mg/L BA. Maximum number of regenerated shoots was up to 10∼12. Adventitious root formation from explants were formed profusely on MS medium with 1.0 mg/L NAA＋2.0 mg/L kinetin. The most desirable method for mass propagation of plantlets was the shoot regeneration from scale segments then subsequently subcultured on medium for rooting.

Emodin, an active anthraquinone constituent isolated from the rhubarb, a traditional Chinese herbal medicine which is widely used in clinical treatment, has cardiovascular protective properties. However, it remains unclear whether the cardiovascular protective actions of emodin are related to an activation of cardiac natriuretic hormone secretion. The purpose of the present study was to explore the effect of emodin on the secretion of ANP, a member of the family of cardiac natriuretic hormones, and its mechanisms involved. Experiments were performed in isolated perfused beating rabbit atria allowing measurement of ANP secretion, atrial pulse pressure, and stroke volume. Emodin increased ANP secretion concomitantly with a decrease in atrial pulse pressure and stroke volume in a concentration-dependent manner. These effects were reversible. Inhibition of K(+) channels with tetraethylammonium and glibenclamide attenuated the emodin-induced changes in ANP secretion and atrial dynamics. Furthermore, the emodin-induced changes in ANP secretion and atrial dynamics were attenuated by inhibition of L-type Ca(2+) channels with nifedipine. Atropine, methoctramine, tertiapin-Q, and pertussis toxin had no significant effect on the emodin-induced changes in ANP secretion and mechanical dynamics. The present study demonstrates that emodin increases ANP secretion via inhibition of L-type Ca(2+) channels through an activation of K(+)ATP channel in isolated beating rabbit atria. The results also provide a rationale for the use of emodin in the treatment of impairment of the regulation of the cardiovascular homeostasis.

Mesangial cell proliferation is correlated with the progression of renal failure. The purpose of this study was to determine whether a water extract of Poria cocos Wolf (WPC), a well-known medicinal plant, regulates rat mesangial cell proliferation in the presence of high glucose (HG). HG significantly accelerated [3H]-thymidine incorporation, which was inhibited by WPC (1–50 μg/mL) in a dose-dependent manner. Cell migration and fibronectin mRNA expression data also supported the anti-proliferative effect of WPC. Western blot analysis revealed that pretreatment with WPC decreased the expression of cyclins and cyclin-dependent kinases (CDKs) and promoted the expression of p21waf1/cip1and p27kip1. WPC also suppressed HG-induced p38 mitogen-activated protein kinase (p38 MAPK) and extracellular-signal-regulated kinase 1/2 (ERK 1/2) phosphorylation. Furthermore, WPC inhibited HG-induced production of dichlorofluorescein (DCF)-sensitive intracellular reactive oxygen species (ROS). In conclusion, HG promoted mesangial cell proliferation, and WPC inhibited this activity, at least in part, via induction of cell cycle arrest and activation of anti-oxidant properties. Taken together, these results suggest that P. cocos may be a potent regulator of HG-induced proliferation.

Ethnopharmacological relevance Euphorbia humifusa Willd. (EH) is an important traditional Chinese medicine that has commonly been used for treating bacillary dysentery and enteritis in many Asian countries for thousands of years. EH has a wide variety of pharmacological actions such as antioxidant, hypotensive, and hypolipidemic effects. However, the mechanisms involved are to be defined. Aim of the study The present study was performed to evaluate the cardiovascular effects of EH in rats. Materials and methods Methanol extract of EH (MEH) and ethylacetate fraction of the MEH (EEH) was examined for their vascular relaxant effects in phenylephrine-precontracted aortic rings. Effects of EEH on systolic blood pressure and heart rate were tested in Sprague–Dawley rats. Results MEH and EEH induced vasorelaxation in a concentration-dependent manner. Endothelium-denudation abolished the EEH-induced vasorelaxation. Pretreatment of the endothelium-intact aortic rings with N G -nitro- l -arginine methylester ( l -NAME) and 1 H -[1,2,4]-oxadiazolo-[4,3-α]-quinoxalin-1-one (ODQ) significantly inhibited the EEH-induced vasorelaxation. EEH increased cGMP levels of the aortic rings in a concentration-dependent manner and the effect was blocked by l -NAME or ODQ. Extracellular Ca 2+ depletion and treatments with thapsigargin, Gd 3+ , and 2-aminoethyl diphenylborinate significantly attenuated the EEH-induced vasorelaxation. Wortmannin markedly attenuated the EEH-induced vasorelaxation. In addition, tetraethylammonium, iberiotoxin, and charybdotoxin, but not apamin, attenuated the EEH-induced vasorelaxation. Glibenclamide, indomethacin, atropine, and propranolol had no effects on the EEH-induced vasorelaxation. Furthermore, EEH decreased systolic blood pressure and heart rate in a concentration-dependent manner in rats. Conclusions The present study demonstrates that EEH induces endothelium-dependent vasorelaxation via eNOS-NO-cGMP signaling through the modification of intracellular Ca 2+ , Ca 2+ entry, and large- and intermediate-conductance K Ca channel homeostasis. The data also suggest that the Akt-eNOS pathway is involved in the EEH-induced vasorelaxation. EEH induces hypotension and bradycardia in vivo .