Discovery of 4'-trifluoromethylchalcones as novel, potent and selective hCYP1B1 inhibitors without concomitant AhR activation.

Human cytochrome P450 1B1 (hCYP1B1), an extrahepatic cytochrome P450 enzyme over-expressed in various tumors, has been validated as a promising target for preventing and treating cancers. Herein, two series of chalcone derivatives were synthesized to discover potent hCYP1B1 inhibitors without AhR agonist effect. Structure-activity relationship (SAR) studies demonstrated that 4'-trifluoromethyl on the B-ring strongly enhanced the anti-hCYP1B1 effects, identifying A9 as a promising lead compound. Further SAR analysis on A9 derivatives (modified A-ring of 4'-trifluoromethylchalcone) showed that introducing 2-methoxyl improved the anti-hCYP1B1 effect and selectivity, while introducing a methoxyl at the C-4 site was beneficial for avoiding AhR activation. Ultimately, five 4'-trifluoromethyl chalcones were identified as potent hCYP1B1 inhibitors (IC50 < 10 nM), while B18 exhibits the most potent anti-hCYP1B1 effect (IC50 = 3.6 nM), suitable metabolic stability and good cell-permeability. B18 also acted as an AhR antagonist and could down-regulate hCYP1B1 in living systems. Mechanistic studies showed that B18 potently inhibited hCYP1B1 in a competitive inhibition manner (Ki = 3.92 nM), while docking simulations revealed that B18 could tightly bind to the catalytic cavity of hCYP1B1 mainly via hydrophobic and hydrogen-bonding interactions. Furthermore, B18 could potently inhibit hCYP1B1 in living cells and showed remarkable anti-migration ability on MFC-7 cells. Taken together, this study deciphered the SARs of chalcones as hCYP1B1 inhibitors and provided several potent hCYP1B1 inhibitors as promising candidates for the development of more efficacious anti-migration agents.

Folium Ginkgo extract and tetramethylpyrazine sodium chloride injection (Xingxiong injection) protects against focal cerebral ischaemia/reperfusion injury via activating the Akt/Nrf2 pathway and inhibiting NLRP3 inflammasome activation.

CONTEXT: Folium Ginkgo extract and tetramethylpyrazine sodium chloride injection (Xingxiong injection) is a compound preparation commonly used for treating cerebral ischaemia/reperfusion injury in ischaemic stroke in China. However, its potential mechanisms on ischaemic stroke remain unknown. OBJECTIVE: This study explores the potential mechanisms of Xingxiong injection in vivo or in vitro. MATERIALS AND METHODS: Sprague-Dawley (SD) rats were randomly assigned to five groups: the sham (normal saline), the model (normal saline) and the Xingxiong injection groups (12.5, 25 or 50 mL/kg). The rats were subjected to 2 h of middle cerebral artery occlusion (MCAO) followed by reperfusion for 14 d. Xingxiong injection was administered via intraperitoneal (i.p.) injection immediately after ischaemia induction for 14 d. Afterwards, rats were sacrificed at 14 d induced by administration of Xingxiong injection. RESULTS: Xingxiong injection significantly reduces infarct volume (23%) and neurological deficit scores (93%) compared with the MCAO/R group. Additionally, Xingxiong injection inhibits the loss in mitochondrial membrane potential (43%) and reduces caspase-3 level (44%), decreases NOX (41%), protein carbonyl (29%), 4-HNE (40%) and 8-OhdG (41%) levels, inhibits the expression of inflammatory factors, such as TNF-α (26%), IL-1ß (34%), IL-6 (39%), MCP-1 (36%), CD11a (41%) and ICAM-1 (43%). Moreover, Xingxiong injection can increase p-Akt/Akt (35%) and Nrf2 (47%) protein expression and inhibit NLRP3 (42%) protein expression. CONCLUSIONS: Xingxiong injection prevents cerebral ischaemia/reperfusion injury via activating the Akt/Nrf2 pathway and inhibiting NLRP3 inflammasome. These findings provide experimental evidence for clinical use of drugs in the treatment of ischaemic stroke.

Guan Xin Dan Shen formulation protects db/db mice against diabetic cardiomyopathy via activation of Nrf2 signaling.

Guan Xin Dan Shen formulation (GXDSF) is a widely used treatment for the management of coronary heart disease in China and is composed of three primary components: Dalbergiae odoriferae Lignum, Salviae miltiorrhizae Radix et Rhizoma and Panax notoginseng Radix et Rhizoma. However, the potential use of GXDSF for the management of diabetic cardiomyopathy (DCM) has not been previously assessed. The present study aimed to assess the effects of GXDSF on DCM, as well as the underlying mechanism. In the present study, db/db mice were used. Following treatment with GXDSF for 10 weeks, fasting blood glucose, insulin sensitivity, serum lipid levels and cardiac enzyme levels were detected. Cardiac pathological alterations and cardiac function were assessed by performing hematoxylin and eosin staining and echocardiograms, respectively. TUNEL assays were conducted to assess cardiomyocyte apoptosis. Additionally, reverse transcription­quantitative PCR and western blotting were performed to evaluate the expression of apoptosis­associated genes and proteins, respectively. In the model group, the db/db mice displayed obesity, hyperlipidemia and hyperglycemia, accompanied by noticeable myocardial hypertrophy and diastolic dysfunction. Following treatment with GXDSF for 10 weeks, serum triglyceride levels were lower and insulin sensitivity was enhanced in db/db mice compared with the model group, which indicated improvement in condition. Cardiac hypertrophy and dysfunction were also improved in db/db mice following treatment with GXDSF, resulting in significantly increased left ventricular ejection fraction and fractional shortening compared with the model group. Following treatment with metformin or GXDSF, model­induced increases in levels of myocardial enzymes were decreased in the moderate and high dose groups. Moreover, the results indicated that, compared with the model group, GXDSF significantly inhibited cardiomyocyte apoptosis in diabetic heart tissues by increasing Bcl­2 expression and decreasing the expression levels of Bax, cleaved caspase­3 and cleaved caspase­9. Mechanistically, GXDSF enhanced Akt phosphorylation, which upregulated antioxidant enzymes mediated by nuclear factor erythroid 2­related factor 2 (Nrf2) signaling. Collectively, the results of the present study indicated that GXDSF attenuated cardiac dysfunction and inhibited cardiomyocyte apoptosis in diabetic mice via activation of Akt/Nrf2 signaling. Therefore, GXDSF may serve as a potential therapeutic agent for the management of DCM.

Notoginsenoside R1 activates the NAMPT-NAD+-SIRT1 cascade to promote postischemic angiogenesis by modulating Notch signaling.

Nicotinamide phosphoribosyltransferase (NAMPT) maintains mitochondrial function and protects against cerebral ischemic injury by improving energy metabolism. Notoginsenoside R1 (R1), a unique constituent of Panax notoginseng, has been shown to promote the proliferation and tube formation of human umbilical vein endothelial cells. Whether R1 has proangiogenesis on the activation of NAMPT in ischemic stroke remains unclear. The purpose of this study was to investigate the pharmacodynamic effect and mechanism of R1 on angiogenesis after ischemic stroke. We used male Sprague-Dawley (SD) rats subjected to middle cerebral artery occlusion/reperfusion (MCAO/R). R1 was administered via intraperitoneal (i.p.) injection immediately after ischemia induction. The promotion of R1 on angiogenesis were detected by immunofluorescence staining, 3D stereoscopic imaging and transmission electron microscopy detection. HBMEC cells were pretreated with different concentrations of R1 for 12 h before oxygen-glucose deprivation/reoxygenation (OGD/R) exposure. Afterward, scratch assay, EdU staining and tube formation were determined. Western blot analyses of proteins, including those involved in angiogenesis, NAMPT-SIRT1 cascade, VEGFR-2, and Notch signaling, were conducted. We showed that R1 significantly restored cerebral blood flow, improved mitochondrial energy metabolism and promoted angiogenesis. More importantly, incubation with 12.5-50 µM R1 significantly increased the migration, proliferation and tube formation of HBMECs in vitro. The promotion of R1 on angiogenesis were associated with the NAMPT-NAD+-SIRT1 cascade and Notch/VEGFR-2 signaling pathway, which was partially eliminated by inhibitors of NAMPT and SIRT1. We demonstrated that R1 promotes post-stroke angiogenesis via activating NAMPT-NAD+-SIRT1 cascade. The modulation of Notch signaling and VEGFR-2 contribute to the post-stroke angiogenesis. These findings offer insight for exploring new therapeutic strategies for neurorestoration via R1 treatment after ischemic stroke.

Effects of notoginseng leaf triterpenes on small molecule metabolism after cerebral ischemia/reperfusion injury assessed using MALDI-MS imaging.

BACKGROUND: Notoginseng leaf triterpenes (PNGL) is believed to have neuroprotective effects via the inhibition of inflammatory response and neuronal apoptosis. However, its mechanisms underlying the anti-ischemia/reperfusion (I/R) injury effects on the regulation of small molecule metabolism in rat brain remains unclear. The purpose of this study was thus to explore the mechanisms of PNGL on the regulation of small molecule metabolism in rat brain after I/R injury using matrix-assisted laser desorption ionization-mass spectrometry imaging (MALDI-MSI). METHODS: As a model of in vivo cerebral I/R injury, male Sprague-Dawley (SD) rats were established with a middle cerebral artery occlusion/reperfusion (MCAO/R) model after PNGL administration with 40 mg·kg-1 through intraperitoneal injection (i.p.) for 7 days. We assessed the neurological behavior, regional cerebral blood flow (r CBF), neuron injury, and spatial distribution of metabolic small molecules. RESULTS: Our in vivo results suggested that PNGL increased cerebral blood flow and relieved neurological dysfunction. Furthermore, using MALDI-MSI, we demonstrated that PNGL regulated 16 endogenous small molecules implicated in metabolic networks including tricarboxylic acid (TCA) cycle, adenosine triphosphate (ATP) metabolism, malate-aspartate shuttle, metal ions, and antioxidants underwent noticeable changes after reperfusion for 24 h. CONCLUSIONS: PNGL is a novel cerebrovascular agent that can improve cerebral blood flow and attenuate adverse neurological disorders. The mechanisms are closely correlated with relative metabolic pathways, which offers insight into exploring new mechanisms in PNGL for the treatment of cerebral I/R injury.

Diagnostic Accuracy of the Synovial Fluid α-Defensin Lateral Flow Test in Periprosthetic Joint Infection: A Meta-analysis.

OBJECTIVES: There is a controversy on the diagnostic reliability and accuracy of synovial fluid α-defensin in periprosthetic joint infection (PJI). We performed this meta-analysis to evaluate the diagnostic accuracy of the α-defensin lateral flow test in PJI. METHODS: PubMed, Embase, and the Cochrane library were systematically searched, and articles (up to January 2020) on the diagnosis of hip and knee PJIs using the α-defensin Synovasure lateral flow test were included. The diagnostic accuracy of the α-defensin lateral flow test in PJI was evaluated using meta-analysis. The pooled sensitivity, specificity, accuracy, positive and negative likelihood ratio, diagnostic odds ratio, and post-test probabilities were calculated. RESULTS: Seventeen studies including 1443 cases were included. Meta-analysis showed the pooled sensitivity, specificity, positive likelihood ratio, negative likelihood ratio, and a diagnostic odds ratio was 0.83 (95% CI 0.77, 0.88), 0.95 (95% CI 0.93, 0.97), 16.86 (95% CI 11.67, 24.37), 0.17 (95% CI 0.13, 0.24) and 85.30 (95% CI 47.76, 152.35), respectively. The area under the hierarchical summary receiver operating characteristic curve was 0.97 (95% CI 0.95, 0.98). Subgroup analysis also confirmed the high efficiency of α-defensin Synovasure lateral flow test in diagnosing PJIs, irrespective of ethnicity. Fagan's nomogram analysis there was a high positive post-test probability of 94% and a low negative post-test probability of 15%. CONCLUSIONS: We indicated that the α-defensin lateral flow test had a high accuracy for diagnosing PJI. Large-scale studies are needed to validate its significance in PJI diagnosis.

Xuesaitong injection (lyophilized) combined with aspirin and clopidogrel protect against focal cerebral ischemic/reperfusion injury in rats by suppressing oxidative stress and inflammation and regulating the NOX2/IL-6/STAT3 pathway.

BACKGROUND: Combination of aspirin (ASA) and clopidogrel (CLP) [dual antiplatelet therapy (DAPT)] has been limited in reducing early recurrent stroke events. Xuesaitong injection (lyophilized) (XST) made of total saponins from P. notoginseng, which significantly improves cerebral circulation and has been widely used in clinical applications for decades to treat and prevent ischemic stroke. Here, we confirmed the protective effect and mechanism of XST combined with DAPT (XST+ASA+CLP) on cerebral ischemia/reperfusion injury, exploring their better pharmacological action for clinical patients. METHODS: Sprague-Dawley rats (SD rats) (n=9 in each group) were randomly assigned to three groups and pretreated with XST, ASA+CLP, or XST+ASA+CLP for 7 days. Then rats were subjected to 2 h of middle cerebral artery occlusion (MCAO) followed by reperfusion for 24 h. Therapeutic effect of XST+ASA+CLP was measured by infarct volume, neurological behavior and regional cerebral blood flow (rCBF). Inhibition of neuronal apoptosis and glial cells was determined by immunofluorescent staining. We studied the protein levels of neurotrophic factors, neuroplasticity-related factors, oxidative stress indicators and inflammatory factors by ELISA assay. RESULTS: XST+ASA+CLP group showed significant reduction in infarct volumes and neurological deficit scores. XST+ASA+CLP group also had higher levels in rCBF and synaptic growth, and showed remarkable inhibition of microglia and astrocytes activation and the neuronal apoptosis. In addition, XST+ASA+CLP group had lower levels of NADPH, protein carbonyl, 4-hydroxynonenal (4-HNE), 8-hydroxydeoxyguanosine (8-OHdG) and several inflammatory cytokines. Moreover, XST+ASA+CLP group also had lower levels of NOX2, inducible nitric oxide synthase (iNOS), interleukin (IL)-6, and p-STAT3/STAT3. CONCLUSIONS: These results demonstrate that a combination of XST, ASA, and CLP effectively protected rats against middle cerebral artery occlusion/reperfusion (MCAO/R) injury by suppressing the NOX2/IL-6/ STAT3 pathway. These novel findings provide theoretical basis and experimental evidence for the rationality of clinical combined use of drugs in the treatment of ischemic stroke.

[Effect of Guanxin Danshen Formulation on diabetic kidney disease in db/db mice through regulation of Nrf2 pathway].

Diabetic kidney disease(DKD) has become a primary cause of end-stage kidney disease, without any effective treatment available. In this study, we assessed the protective effect of Guanxin Danshen Formulation(GXDSF) on diabetic nephropathy in db/db mice. The db/m and db/db mice were randomly divided into 4 groups: control group, model group, metformin group, and GXDSF group. After 8 weeks' treatment with GXDSF, metformin or normal saline, the mice were sacrificed, and the blood and kidney tissues were collected for the further analysis. Compared with the model group, TG, TCH and LDL levels significantly decreased in the GXDSF group. The results from HE and PAS staining showed that db/db mice exhibited abnormal kidney tissues with increased glomerular volume, basement-membrane thickening and mesangial cell proliferation, which could be significantly alleviated by GXDSF treatment. GXDSF treatment also reduced serum creatinine and BUN. Meanwhile, GXDSF treatment markedly elevated GSH-PX levels, while reduced LDH and MDA levels in the kidney tissues. Western blot assay showed that GXDSF evidently up-regulated protein levels of ERα and p-Akt, and subsequently promoted HO-1 expression mediated by Nrf2. These data collectively indicated that GXDSF protects db/db mice against DN by regulating ERα and Nrf2-mediated HO-1 expression.

Scutellarin protects against myocardial ischemia-reperfusion injury by suppressing NLRP3 inflammasome activation.

BACKGROUND: Activation of NLRP3 inflammasome plays a key role in cardiac dysfunction for acute myocardial ischemia-reperfusion injury. Scutellarin (Scu) is a flavonoid purified from Erigeron breviscapus. Whether Scu has any influence on the activation of NLRP3 inflammasome in cardiomyocytes remains unknown. PURPOSE: We aimed to examine the therapeutic effect of Scu on cardiomyocyte ischemia-reperfusion (I/R) injury and its effect on NLRP3 inflammasome in rats with acute myocardial I/R injury and anoxia/reoxygenation (A/R)-induced H9c2 injuries. METHODS: Heart injuries were induced through 30 min of ischemia followed by 24 h of reperfusion. Scu was intraperitoneally administered 15 min before vascular ligation. Effects of Scu on cardiac injury were detected by echocardiograms, TTC staining, and histological and immunohistochemical analyses. The effects of Scu on biochemical parameters were analyzed. H9c2 cells were pretreated with different concentrations of Scu for 6 h before A/R exposure. Afterward, cell viability, LDH release, and Hoechst 33342 and peromide iodine double staining were determined. Western blot analyses of proteins, including those involved in autophagy, NLRP3, mTOR complex 1 (mTORC1), and Akt signaling, were conducted. RESULTS: In vivo study revealed that Scu improved diastolic dysfunction, ameliorated myocardium structure abnormality, inhibited myocyte apoptosis and inflammatory response, and promoted autophagy. Scu reduced NLRP3 inflammasome activation, inhibited mTORC1 activity, and increased Akt phosphorylation. In vitro investigation showed the same results. The Scu-mediated NLRP3 inflammasome and mTORC1 inhibition and cardioprotection were abolished through the genetic silencing of Akt by siRNA. CONCLUSIONS: The cardioprotective effect of Scu was achieved through its anti-inflammatory effect. It suppressed the activation of NLRP3 inflammasome. In addition, inflammasome restriction by Scu was dependent on Akt activation and mTORC1 inhibition.

[Effect of moxibustion on clinical symptoms, peripheral inflammatory indexes and T lymphocyte subsets in COVID-19 patients].

OBJECTIVE: To explore the therapeutic effect and the mechanism of the adjuvant treatment with moxibustion on coronavirus disease 2019 (COVID-19). METHODS: A total of 95 patients with COVID-19 were randomly divided into a moxibustion group (45 cases) and a basic treatment group (50 cases). The routine treatment of western medicine was applied in the patients of both groups. In the moxibustion group, on the base of the treatment of western medicine, moxibustion was applied to Dazhui (GV 14), Feishu (BL 13), Qihai (CV 6) and Zusanli (ST 36), once daily and consecutively for 14 days. At the end of treatment courses, clinical symptom scores for cough, asthmatic breathing, chest oppression and short breath, as well as their remission rates were compared between the two groups before and after treatment. Before and after treatment, the white blood cell (WBC) count, the levels of c-reactive protein (CRP) and interleukin-6 (IL-6) and the absolute number of T lymphocyte subsets, i.e. , and of the peripheral blood were compared in the patients between the two groups. The principal component analysis was adopted to analyze the common data extracted from the above 10 clinical indexes variables and comprehensively evaluate the differences in the therapeutic effect of two regimens. RESULTS: The clinical symptom scores were all decreased after treatment in both of the moxibustion group and the basic treatment group as compared with those before treatment (P<0.05). After treatment, the clinical symptom scores of cough, chest oppression and asthmatic breathing in the moxibustion group were lower significantly than those in the basic treatment group (P<0.05) and the remission rates of cough, chest oppression and asthmatic breathing were higher than the basic treatment group (P<0.05). After treatment, WBC count was increased as compared with that before treatment in either group (P<0.05) and the levels of CRP and IL-6 in the moxibustion group were reduced as compared with those before treatment (P<0.05). The reducing range of IL-6 level in the moxibustion group was larger than the basic treatment group (P<0.05). After treatment, the absolute number of , and T lymphocytes was increased as compared with that before treatment in the moxibustion group (P<0.05), and its increase range was larger than the basic treatment group (P<0.05). The difference value was 33.38 for the score of comprehensive evaluation before and after treatment in the moxbustion group, higher obviously than 8.91 in the basic treatment group. CONCLUSION: On the base of the routine treatment with western medicine, moxibustion therapy supplemented relieves the clinical symptoms, reduces the levels of inflammatory indexes, i.e. IL-6 and CRP as well as improves the absolute number of peripheral T lymphocyte subsets. The clinical therapeutic effect of such regimen with moxibustion supplemented is significantly better than the simple routine treatment of western medicine.

Jinbei Oral Liquid ameliorates bleomycin-induced idiopathic pulmonary fibrosis in rats via reversion of Th1/Th2 shift.

Objective: Idiopathic pulmonary fibrosis (IPF) is a progressive and lethal interstitial lung disease with high mortality. The pivotal role of Th1/Th2 immunological balance in the development and progression of IPF has been demonstrated previously. This study aimed to evaluate the effect of Jinbei Oral Liquid (JBOL) on IPF and its relationship with Th1/Th2 shift. Methods: Rats were divided into six groups: control group, model group (bleomycin), pirfenidone group (positive group, 54 mg/kg, i.g.) and JBOL (5.4, 10.8 and 21.6 mL/kg, i.g.) groups. The rat model was established by an intratracheal instillation of bleomycin (BLM, 5 mg/kg). One day after injection of BLM, pirfenidone or JBOL was given to rats once daily within 28 consecutive days, respectively. Positron emission tomography/computed tomography (PET/CT) was performed on the treated rats. The extent of alveolitis and fibrosis was observed by H&E and Masson trichrome staining. The contents of TGF-ß1, TNF-α, IL-4 and IFN-γ were further quantified by ELISA assay. Results: PET/CT and histopathological evidence showed the ability of JBOL to attenuate bleomycin-induced alveolitis and fibrosis extent, and the alveolitis lesion score was markedly decreased compared with the model group. The increased expression of inflammatory cytokines TGF-ß1 and TNF-α induced by bleomycin was also suppressed by JBOL. The Th1 response was limited by the reduced IFN-γ after BLM administration, and the Th2 response predominated significantly marked by the increased IL-4. JBOL could increase the level of IFN-γ and markedly increased the ratio of IFN-γ/IL-4. Conclusion: These findings suggested that JBOL may attenuate BLM-induced idiopathic pulmonary fibrosis via reducing inflammatory cell infiltration, pro-inflammatory cytokine release and excessive collagen deposition in rats. One of the mechanisms is the reversion of Th1/Th2 shift caused by BLM.

Shenkang Injection protects against diabetic nephropathy in streptozotocin (STZ)-induced mice through enhancement of anti-oxidant and anti-inflammatory activities.

Objective: To investigate the protective effects and possible mechanisms of Shenkang Injection (SKI) on the diabetic nephropathy in streptozotocin-induced mice. Methods: STZ with the feeding of high fat diet (HFD) was used to induce diabetic mice. The balb/c mice and diabetic mice were then randomly divided into five groups: (1) control group, (2) model group, (3) alprostadil (Alp, 1.5 µg/kg) group, (4) SKI (30 ml/kg) group, (5) Alp (1.5 µg/kg) + SKI (15 ml/kg) group. After six weeks' treatment, blood, urine and kidney tissues were collected for biochemical assay, ELISA assay, and pathological analysis. Results: Diabetic mice exhibited evident manifestations of diabetic nephropathy (DN), as indicated by increased 24-h urine volume, urinary albumin and kidney weight index (P < 0.01), which could be attenuated by SKI treatment (P < 0.01). SKI was further found to improve abnormal morphology in glomerulus with increased glomerular volume and to decrease urinary N-acetyl-b-D-glucpsaminidase (NAG), ß2-microglobulin (ß2-MG), and kidney injury molecules-1 (KIM-1) levels (P < 0.05, P < 0.01). Plasma levels of anti-oxidant enzymes significantly reduced in the diabetic mice, and those decreases could be reversed by SKI and Alp treatments. Additionally, SKI obviously suppressed the diabetes-induced increases of pro-inflammatory cytokines (IL-6, IL-1ß and TNF-α) (P < 0.01). Meanwhile, SKI was found to effectively attenuate the diabetes-induced coagulation dysfunction, as evidenced by lengthening prothrombin and thrombin time, and decreasing plasma levels of fibrinogen (FIB), 6-K-PGF1α and thromboxane B2 (TXB2) (P < 0.05, P < 0.01). With SKI and Alp combined treatment, the anti-oxidant activities and improvements of coagulation dysfunction were enhanced. Conclusion: SKI possesses a remarkable property to prevent diabetic nephropathy. The improvements of kidney function and hypercoagulability by SKI were enhanced with Alp combined treatment. The molecular mechanisms underlying the protection of SKI against DN may be related to enhancing the anti-oxidant and anti-inflammatory activities, and improving the coagulation dysfunction.

Protective effects of Myrica rubra flavonoids against hypoxia/reoxygenation-induced cardiomyocyte injury via the regulation of the PI3K/Akt/GSK3ß pathway.

Myrica rubra is well known for its delicious taste and high nutritional value. The present study investigated the potential protective effects and mechanisms of M. rubra flavonoids (MRF) extract on isoproterenol (ISO)­induced myocardial injury in rats and hypoxia/reoxygenation (H/R) injury in H9c2 cardiomyocytes. An in vivo study revealed that MRF decreased serum cardiac enzyme levels, ameliorated pathological heart alterations and increased the antioxidant potential. The in vitro investigation demonstrated that MRF inhibited cell death, reactive oxygen species (ROS) accumulation, mitochondrial membrane depolarization, apoptosis rate and caspase­3 activation and enhanced the Bcl­2/Bax ratio during H/R injury. These effects were accompanied by the phosphorylation of protein kinase B (Akt) and glycogen synthase kinase (GSK)­3ß. Further mechanism studies demonstrated that LY294002, a specific inhibitor of phosphoinositide 3­kinase (PI3K), abolished the MRF­mediated cardioprotection against H/R­induced apoptosis and ROS overproduction. Collectively, these results suggested that MRF exerts cardioprotective effects by attenuating oxidative damage and cardiomyocyte apoptosis most likely via a PI3K/Akt/GSK3ß­dependent mechanism.

Cytochrome P450 3A Enzymes Are Key Contributors for Hepatic Metabolism of Bufotalin, a Natural Constitute in Chinese Medicine Chansu.

Bufotalin (BFT), one of the naturally occurring bufodienolides, has multiple pharmacological and toxicological effects including antitumor activity and cardiotoxicity. This study aimed to character the metabolic pathway(s) of BFT and to identify the key drug metabolizing enzyme(s) responsible for hepatic metabolism of BFT in human, as well as to explore the related molecular mechanism of enzymatic selectivity. The major metabolite of BFT in human liver microsomes (HLMs) was fully identified as 5ß-hydroxylbufotalin by LC-MS/MS and NMR techniques. Reaction phenotyping and chemical inhibition assays showed that CYP3A4 and CYP3A5 were key enzymes responsible for BFT 5ß-hydroxylation. Kinetic analyses demonstrated that BFT 5ß-hydroxylation in both HLMs and human CYP3A4 followed the biphasic kinetics, while BFT 5ß-hydroxylation in CYP3A5 followed substrate inhibition kinetics. Furthermore, molecular docking simulations showed that BFT could bind on two different ligand-binding sites on both CYP3A4 and CYP3A5, which partially explained the different kinetic behaviors of BFT in CYP3A4 and CYP3A5. These findings are very helpful for elucidating the phase I metabolism of BFT in human and for deeper understanding the key interactions between CYP3A enzymes and bufadienolides, as well as for the development of bufadienolide-type drugs with improved pharmacokinetic and safety profiles.

A new cadinane sesquiterpenoid glucoside with cytotoxicity from Abelmoschus sagittifolius.

A new cadinane sesquiterpenoid glucoside, 2ß,7,3-trihydroxycalamenene 3-O-ß-d-glucoside (1) together with six known compounds, N-(p-trans-coumaroyl)-N-methyl tyramine (2), Cleomiscosin A (3), 9,12,13-trihydroxy-10,15-heptadecadienoic acid (4), Cytochalasin B (5), Marmesinin (6) and N-(p-trans-coumaroyl) tyramine (7) were obtained from the stem bark of Abelmoschus sagittifolius. The new structure of compound 1 was elucidated by analysing its 1H and 13C-NMR, 1H-1H COSY, HSQC, HMBC, NOESY and HR-ESI-MS spectra. Compounds 1-7 showed moderate cytotoxicity against Hela and HepG-2 human cancer cell lines.

Salvianolic Acid A Ameliorates Arsenic Trioxide-Induced Cardiotoxicity Through Decreasing Cardiac Mitochondrial Injury and Promotes Its Anticancer Activity.

Arsenic trioxide (ATO) is used as a therapeutic agent in the treatment of acute promyelocytic leukemia (APL). The therapeutic use of arsenic is limited due to its severe cardiovascular side effects. The cardio-protective effect of salvianolic acid A (Sal A) against ATO cardiotoxicity has been reported. However, the distinct role of the mitochondria in the cardio-protection of Sal A is not understood. The aim of this study was to determine whether Sal A preconditioning protects against ATO-induced heart injury by maintaining cardiac mitochondrial function and biogenesis. For the in vivo study, BALB/c mice were treated with ATO and/or Sal A. For the in vitro study, we determined the effects of ATO and/or Sal A in H9c2 cardiomyocytes. Our results showed that ATO induced mitochondrial structural damage, abnormal mitochondrial permeability transition pore (mPTP) opening, overproduction of mitochondrial reactive oxygen species (ROS), and decreased the ATP content. Sal A pretreatment alleviated the ATO-induced mitochondrial structural and functional damage. In this study, ATO decreased the expression level of the peroxisome proliferator activator receptor gamma-coactivator 1 (PGC-1α) and disrupted the normal division and fusion of mitochondria. Sal A pretreatment improved the dynamic balance of the damaged mitochondrial biogenesis. Moreover, the combination treatment of Sal A and ATO significantly enhanced the ATO-induced cytotoxicity of SGC7901, HepaRG, K562 and HL60 cells in vitro. These results indicated that Sal A protects the heart from ATO-induced injury, which correlates with the modulation of mitochondrial function, and the maintenance of normal mitochondrial biogenesis.

Protective effects of total flavonoids from Clinopodium chinense (Benth.) O. Ktze on myocardial injury in vivo and in vitro via regulation of Akt/Nrf2/HO-1 pathway.

BACKGROUND: Clinopodium chinense (Benth.) O. Ktze is a traditional Chinese herbal medicine, which comprises the plant's total flavonoids. TFCC plays an important role in the treatment of cardiovascular disease. PURPOSE: The aim of the study was to study the protective effects and possible mechanism of TFCC against isoproterenol (ISO)-mediated myocardial injury in vivo and anoxia/reoxygenation (A/R)-induced H9c2 cell injury in vitro. METHODS: Male Sprague-Dawley (SD) rats were intragastrically pretreated with TFCC for 15 days. After 2 h of TFCC administration on days 14 and 15, a myocardial injury model was established with intragastric administration of 120 mg/kg of ISO daily for 2 days. The experiment was stopped 12 h after the last administration of the drugs. ECG recordings were taken after the treatment. Serum samples were assayed to determine the serum cardiac enzymes (e.g., creatine kinase, aspartate aminotransferase, and lactate dehydrogenase). The left ventricle was excised for histopathological examination, and myocardial homogenates were prepared to detection catalase, glutathione peroxidase, and superoxide dismutase. Reactive oxygen species (ROS), heme oxygenase-1(HO-1),and peroxidase were detected by the corresponding ELISA kits. H9c2 cells were pretreated with different concentrations of TFCC for 12 h before A/R exposure. Afterward, cell viability, LDH release, hoechst 33,342, and peromide iodine (PI) double staining, JC-1 staining, and ROS examination were determined. Western blot analyses of B-cell lymphoma-2, Bcl-2associated X protein, cleaved cysteinylaspartate specific protease-3 and-9, nuclear factor 2(Nrf2), HO-1 and serine/threonine protein kinase (AKT), and P-AKT were conducted. RESULTS: The pretreatment of TFCC (10, 20, and 40 mg/kg) daily for 15 days prevented ISO-induced myocardial damage, including the decrease in serum cardiac enzymes and cardiomyocyte apoptotic index and improvement in the heart rate and vacuolation. TFCC also improved the free radical scavenging and antioxidant potential, thereby suggesting that one possible mechanism of TFCC-induced cardio protection is mediated by blocking the oxidative stress. To clarify these mechanisms, we performed the in vitro study by A/R-induced cytotoxicity model in H9c2 cells. TFCC pretreatment prevented apoptosis, increased the expression of HO-1, and enhanced the nuclear translocation of Nrf2. TFCC also activated phosphorylation of AKT, whereas the addition of LY294002, which is the pharmacologic inhibitor of PI3K, blocked the TFCC-induced Nrf2/HO-1 activation and cytoprotective effect. CONCLUSIONS: TFCC protects against myocardial injury and enhances cellular antioxidant defense capacity by inducing the phosphorylation of AKT, which subsequently activated the Nrf2/HO-1 signaling pathway.

A new steroidal saponin from Polygonatum sibiricum.

A new furostan type steroidal saponin, kingianoside Z (1), along with four known compounds (2-5), was isolated from the ethanolic extract of Polygonatum sibiricum Delar. ex Redoute. Their structures were determined by spectroscopical method and by comparison with previously reported spectroscopic data. Compounds 3-5 showed significant cytotoxicity against HepG2 cell lines with IC50 values of 14.2, 12.1 and 8.5 µM, respectively.

Calcium homeostasis and endoplasmic reticulum stress are involved in Salvianolic acid B-offered protection against cardiac toxicity of arsenic trioxide.

Arsenic trioxide (ATO) is a potent anticancer agent used to treat acute promyelocytic leukemia. However, its cardiotoxicity limits ATO's widespread clinical use. Previous studies demonstrated that ATO may aggravate Ca2+ overload and promote endoplasmic reticulum stress (ERS). Salvianolic acid B (Sal B) is cardioprotective against ATO and enhances ATO's anticancer activities. The present study assessed whether the Sal B protective effect was related to maintenance of Ca2+ homeostasis and inhibition of ER stress. Male BALB/c mice were injected with ATO or ATO+Sal B once a day via the tail vein for 2 weeks. We then detected the effects of Sal B in real time using adult rat ventricular cardiomyocytes in vitro using an IonOptix MyoCam system. Sal B treatment alleviated ATO-induced abnormal cardiac contractions and Ca2+ homeostasis imbalance. Sal B increased sarcoplasmic reticulum Ca2+-ATPase (SERCA) activity, regulated Ca2+ handling protein expression, and decreased expression of ERS proteins. Our results demonstrate that the cardioprotective effect of Sal B correlates with SERCA modulation, maintenance of Ca2+ homeostasis, and inhibition of ER stress. These findings suggest Sal B may ameliorate ATO cardiotoxicity during clinical application.

A polysaccharide of Dendrobium officinale ameliorates H2O2-induced apoptosis in H9c2 cardiomyocytes via PI3K/AKT and MAPK pathways.

Dendrobium officinale is one valuable traditional Chinese medicine, which has skyscraping medicinal value. Polysaccharide is the main active ingredient in D. officinale; its antioxidant activity is a hot research topic nowadays. Oxidative stress plays an important role in the pathological progress of a variety of cardiovascular disease, as one of key factors of cardiomyocyte apoptosis. This research adopts a model of H2O2 induction-H9c2 cardiomyocytes apoptosis, aiming to study the effect of Dendrobium officinale Polysaccharide (DOP-GY) for cardiomyocyte apoptosis caused by oxidative stress and its possible mechanism. Our results showed that pretreatment of DOP-GY (low dose: 6.25µg/mL, medium dose: 12.5µg/mL, high dose: 25µg/mL) followed by a 2h incubation with 200µM H2O2 elevated the survival rate, cutted the LDH leakage, reduced lipid peroxidation damage, improved the activity of the endogenous antioxidant enzymes. In addition, the pretreatment of DOP-GY significantly inhibited the production of ROS, declined of the mitochondrial membrane potential, down-regulated pro-apoptosis protein and up-regulated anti-apoptosis protein. The protective effect was correlated with the PI3K/Akt and MAPK signal pathway. Collectively, these observations suggest that DOY-GY has the potential to exert cardioprotective effects against H2O2-induced H9c2 cardiomyocyte apoptosis.