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Background: Traditional Chinese medicinal herbs Cortex Moutan and Radix Salviae Milthiorrhizaeare are prescribed together for their putative cardioprotective effects in clinical practice. However, the rationale of the combined use remains unclear. The present study was designed to investigate the cardioprotective effects of paeonol and danshensu (representative active ingredient of Cortex Moutan and Radix Salviae Milthiorrhizae, respectively) on isoproterenol-induced myocardial infarction in rats and its underlying mechanisms. Methodology: Paeonol (80 mg kg¯¹) and danshensu (160 mg kg¯¹) were administered orally to Sprague Dawley rats in individual or in combination for 21 days. At the end of this period, rats were administered isoproterenol (85 mg kg¯¹) subcutaneously to induce myocardial injury. After induction, rats were anaesthetized with pentobarbital sodium (35 mg kg¯¹) to record electrocardiogram, then sacrificed and biochemical assays of the heart tissues were performed. Principal Findings:Induction of rats with isoproterenol resulted in a marked (P<0.001) elevation in ST-segment, infarct size, level of serum marker enzymes (CK-MB, LDH, AST and ALT), cTnI, TBARS, protein expression of Bax and Caspase-3 and a significant decrease in the activities of endogenous antioxidants (SOD, CAT, GPx, GR, and GST) and protein expression of Bcl- 2. Pretreatment with paeonol and danshensu combination showed a significant (P<0.001) decrease in ST-segment elevation, infarct size, cTnI, TBARS, protein expression of Bax and Caspase-3 and a significant increase in the activities of endogenous antioxidants and protein expression of Bcl-2 and Nrf2 when compared with individual treated groups. Conclusions/Significance:This study demonstrates the cardioprotective effect of paeonol and danshensu combination on isoproterenol-induced myocardial infarction in rats. The mechanism might be associated with the enhancement of antioxidant defense system through activating of Nrf2 signaling and anti-apoptosis through regulating Bax, Bcl-2 and Caspase-3. It could provide experimental evidence to support the rationality of combinatorial use of traditional Chinese medicine in clinical practice. [ABSTRACT FROM AUTHOR]

Survivin belongs to the family of genes known as inhibitors of apoptosis, and although it has been implicated in the prevention of cancer, its potential role in burn-induced cardiac injury is unknown. In this study, we investigated the effects of survivin blockade on burn-induced cardiac apoptosis. Using a standardized Sprague-Dawley rat model of third-degree burn injury over 40% of total body surface area, apoptosis was measured in vivo followed by in vitro assessment of burn serum-stimulated cardiomyocytes. Based on the Western blot analyses, real-time PCR, ELISA, and TUNEL, apoptosis and caspase activation both in vivo and in vitro were significantly increased after severe burn injury, while survivin expression was increased (up to 2.90-fold) during the early stage of burn injury and was almost completely abolished 8 h after the burn. Survivin-deficient cardiomyocytes, as well as hearts from rats treated with the survivin inhibitor YM155, exhibited increased caspase-3 protein and mRNA expression and apoptosis ratio at different times after the burn. Furthermore, inhibition of ERK, phosphoinositol 3-kinase contributed the burn serum-induced increase in apoptosis and caspase-3 protein expression, and decreased survivin expression, whereas burn serum-induced increase in apoptosis was attenuated by P38 mitogen-activated protein kinase inhibition. These data identify survivin as a critical anti-apoptotic regulator of cardiomyocytes after burn injury. ERK, P38 MAPK and PI3K were found to be upstream regulators of survivin. [ABSTRACT FROM AUTHOR]

Up-regulation of G-protein-coupled receptors (GPCR) plays key roles in renal hypertension and cardiovascular disease pathogenesis. The present study was designed to examine if lipid-soluble cigarette smoking particles (DSP), nicotine and endotoxin (LPS), induce GPCR up-regulation for thromboxane A2 (TP), endothelin type A (ETA) and type B (ETB) receptors in renal artery, and if intracellular signal mechanisms are involved. Renal artery segments of rats were exposed to DSP, nicotine or LPS, in organ culture for up to 24 hr. The GPCR-mediated contractions were recorded by using a myograph system. Expression of the GPCR was examined by real-time PCR and immunohistochemistry at mRNA and protein levels. Sarafatoxin 6c (S6c, selective ETB receptor agonist), endothelin-1 (ET-1, non-selective ETA and ETB receptor agonist) and 9,11-Dideoxy-9a,11a-methanoepoxy prostaglandin F2a (U46619, a TP receptor agonist) induced contractions were significantly increased after the arterial segments exposed to DSP in a concentration-dependent (0.1-0.4 μl/ml) manner, and S6c also induced a time-dependent contraction, compared to control (dimethyl sulfoxide). This was in parallel with enhanced mRNA expression for ETB receptor but not ETA and TP receptors, while increased protein expression for ETA, ETB and TP receptors was seen. The specific nuclear factor-kappa B (NF-κB) signal pathway inhibitor BMS345541 was applied to link DSP effects to the GPCR up-regulation. It totally abolished ETB receptor up-regulation, but not ETA and TP receptor up-regulations. Our results suggest that DSP transcriptionally up-regulated ETB receptor expression in rat renal artery via NF-κB signal pathways, whereas up-regulation of ETA and TP receptor-mediated contraction may involve post-transcriptional mechanisms. [ABSTRACT FROM AUTHOR]

Background: The seed oil of Zanthoxylum bungeanum Maxim (ZBSO) is considered to be rich source of fatty acids, mainly oleic and linoleic acids, and has been used for the treatment of burns in Chinese medicine. Objective: We evaluated the healing efficacy of ZBSO and explored its possible mechanism on scalded rats. Materials and Methods: Sprague-Dawley rat models with deep second-degree burns were set up, and ZBSO (500 and 1000 μl/wound) was topically applied twice daily for 7 days and then once daily until wound healing. The therapeutic effects of ZBSO were evaluated by observing wound closure time, decrustation time, wound-healing ratio, and pathological changes. Collagen type-III, matrix metalloproteinase-2 (MMP-2), MMP-9, phospho-nuclear factor-κB (p-NF-κB) p65, inhibitor of NF-κB subunit α p-IκBα, and inhibitor of NF-κB subunit α (IκBα) expression were determined using Western blotting. Results: The ZBSO-treated group showed a higher wound-healing ratio and shorter decrustation and wound closure times than the untreated group. The topical application of ZBSO increased collagen synthesis as evidenced by an increase in hydroxyproline level and upregulated expression of collagen type-III on days 7, 14, and 21 posttreatment. A reduction in MMP-2 and MMP-9 expressions also confirmed the collagen formation efficacy of ZBSO. Furthermore, there was a significant increase in superoxide dismutase levels and a decrease in malondialdehyde levels in ZBSO-treated wounds. ZBSO also decreased tumor necrosis factor alpha, interleukin-1 (IL-1) β, and IL-6 levels in serum, upregulated IκBα, and downregulated p-NF-κB p65 and p-IκBα expression in vivo, indicating the anti-inflammatory action of ZBSO. Conclusion: ZBSO has significant potential to treat burn wounds by accelerating collagen synthesis and the anti-inflammatory cascade of the healing process. Abbreviations used: ECL: Enhanced chemiluminescence; ECM: Extracellular matrix; ELISA: Enzyme-linked immunosorbent assay; GC-MS: Gas chromatography-mass spectrometry; HRP: Horseradish peroxidase; HYP: Hydroxyproline; IκBα: Inhibitor of NF-κB subunit α; IL: Interleukin; MDA: Malondialdehyde; MMP: Matrix metalloproteinase-2; NF-κB: Nuclear factor-κB; SFE: Supercritical fluid extraction; SOD: Superoxide dismutase; SSD: Silver sulfadiazine; TCM: Traditional Chinese medicine; TNF: Tumor necrosis factor. [ABSTRACT FROM AUTHOR]

The traditional Chinese medicine bufalin, extracted from toad's skin, has been demonstrated to exert anticancer activities in various kinds of human cancers. The mechanisms of action lie in its capacity to induce apoptosis, or termed type I programmed cell death (PCD). However, type II PCD, or autophagy, participates in cancer proliferation, progression, and relapse, as well. Recent studies on autophagy seem to be controversial because of the dual roles of autophagy in cancer survival and death. In good agreement with previous studies, we found that 100 nM bufalin induced extensive HepG2 cell apoptosis. However, we also noticed bufalin triggered autophagy and enhanced Beclin-1 expression, LC3-I to LC3-II conversion, as well as decreased p62 expression and mTOR signaling activation in HepG2 cells. Blockage of autophagy by selective inhibitor 3-MA decreased apoptotic ratio in bufalin-treated HepG2 cells, suggesting a proapoptotic role of bufalin-induced autophagy. Furthermore, we investigated the underlying mechanisms of bufalin-induced autophagy. Bufalin treatment dose-dependently promoted AMPK phosphorylation while AMPK inhibition by compound C significantly attenuated bufalin-induced autophagy. Taken together, we report for the first time that bufalin induces HepG2 cells PCD, especially for autophagy, and the mechanism of action is, at least in part, AMPK-mTOR dependent. [ABSTRACT FROM AUTHOR]

Genistein, a major phytoestrogen of soy, is considered a potential drug for the prevention and treatment of post-menopausal osteoporosis. Mounting evidence suggested a positive correlation between genistein consumption and bone health both in vivo and in vitro. Earlier studies have revealed that genistein acted as a natural estrogen analogue which activated estrogen receptor and exerted anti-osteoporotic effect. However, it remains unclear whether PTH, the most crucial hormone that regulates mineral homeostasis, participates in the process of genistein-mediated bone protection. In the present study, we compared the therapeutic effects between genistein and nilestriol and investigated whether PTH and its specific receptor PTHR1 altered in response to genistein-containing diet in the animal model of ovariectomy. Our results showed that genistein administration significantly improved femoral mechanical properties and alleviates femoral turnover Genistein at all doses (4.5 mg/kg, 9.0 mg/kg and 18.0 mg/kg per day, respectively) exerted improved bending strength and b-ALP limiting effects than nilestriol in the present study. However, genistein administration did not exert superior effects on bone protection than nilestriol. We also observed circulating PTH restoration in ovariectomized rats receiving genistein at the dose of 18 mg/kg per day. Meanwhile, PTHR1 abnormalities were attenuated in the presence of genistein as confirmed by RT-PCR, Western blot and immunohistochemistry. These findings strongly support the idea that besides serving as an estrogen, genistein could interact with PTH/PTHR1, causing a superior mineral restoring effect than nilestriol on certain circumstance. In conclusion, our study reported for the first time that the anti-osteoporotic effect of genistein is partly PTH/PTHR1-dependent. Genistein might be a potential option in the prevention and treatment of post-menopausal osteoporosis with good tolerance, more clinical benefits and few undesirable side effects. [ABSTRACT FROM AUTHOR]