Dioscin alleviates myocardial infarction injury via regulating BMP4/NOX1-mediated oxidative stress and inflammation.

BACKGROUND: Dioscin, a steroidal saponin natural product, has various pharmacological activities, such as anti-inflammatory, antioxidant, lipid-lowering. However, little is known about its effects on myocardial infarction (MI) injury. Thus, the study aimed to investigate the protective effects and possible mechanisms of dioscin. METHODS: We evaluated protective effects of Dioscin on HL-1 cells after hypoxia based on MTT and ROS in vitro. In vivo, we ligated left anterior descending (LAD) of C57BL/6 mice to establish MI model and assess serum levels of LDH, CK-MB, cTnI, SOD, MDA and CAT treated by dioscin. In addition, myocardial damages were reflected by H&E, masson and ultrastructural examination and Electrocardiograph (ECG) was detected in MI mice. And the BMP4/NOX1 pathway was measured by western blotting, immunofluorescence assay and Real-time PCR. Furthermore, to investigate cardio-protective effects of dioscin via targeting BMP4, we transfected siBMP4 into HL-1 cells in vitro and injected BMP4 siRNA though tail veins in vivo. RESULTS: In vitro, dioscin significantly increased the viability of HL-1 cells and inhibited ROS level under hypoxia. In vivo, dioscin markedly reduced the elevation of ST segment and alleviated myocardial infarct area in mice. In terms of serology, dioscin evidently decreased LDH, CK-MB, cTnI, MDA levels, and increased SOD level. In addition, dioscin improved the pathological status of myocardial tissue and restrained the production of collagen fibers. Mechanism study proved that dioscin notablely regulated the levels of Nrf2, Keap1, HO-1, p-NF-κB, nNF-κB, TNF-α, IL-1ß and IL-6 by down-regulating the protein levels of BMP4 and NOX1 against oxidative stress and inflammation. Further investigation showed that siBMP4 transfection diminished hypoxia and MI-induced oxidative and inflammation injury. The transfection decreased LDH, CK-MB and cTnI levels, improved ischemia T-wave inversion and reduced striated muscle necrosis, nucleus dissolution, collagen fibrosis and mitochondrial swelling in mice. In addition, siBMP4 decreased ROS and MDA levels, increased SOD and CAT levels and down-regulated mRNA levels of TNF-α, IL-1ß and IL-6. Moreover, BMP4, NOX1 and nNF-κB protein levels were decreased and Nrf2 levels were increased by siBMP4. CONCLUSION: Our study confirmed that dioscin showed an outstanding anti-myocardial infarction effect via regulating BMP4/NOX1-mediated oxidative stress and inflammation, which has a promising application value and development prospect against MI injury in the future.

Effect of education and muscle relaxation program on anxiety, depression and care burden in caregivers of acute stroke survivors: A randomized, controlled study.

ABSTRACT: This study intended to discover the effect of education and muscle relaxation (EMR) program on anxiety, depression and care burden among caregivers of acute stroke survivors.This randomized, controlled study enrolled a total of 110 caregivers of first-ever acute stroke patients, and randomly assigned to EMR (N = 55) and control (N = 55) groups. The caregivers in the EMR group received 12-month health education and progressive muscle relaxation, and those in control group were provided common rehabilitation advices. Hospital Anxiety and Depression Scale (HADS) and Zarit Caregiver Burden Scale in caregivers were evaluated at the time of patients' discharge from hospital (M0), then at month(M) 3, M6 and M12 after the discharge.HADS-anxiety score, anxiety rate and severity were similar at M0, M3, while were reduced at M6 and M12 in EMR group compared to control group. Furthermore, HADS-depression score was similar at M0 and M3 but was decreased at M6 and M12 in EMR group compared with control group, however, there was no difference of depression rate and severity between the 2 groups at each time point. Moreover, Zarit Caregiver Burden Scale score was similar at M0 and M3, but was decreased at M6 and M12; meanwhile, degree of care burden was similar at M0, M3 and M6, but was reduced at M12 in EMR group compared to control group.EMR program decreases anxiety, depression and care burden in caregivers of acute stroke survivors, suggesting its potential in improving mental health and further promoting quality of lives in these caregivers.

Improving the pharmacokinetic and CYP inhibition profiles of azaxanthene-based glucocorticoid receptor modulators-identification of (S)-5-(2-(9-fluoro-2-(4-(2-hydroxypropan-2-yl)phenyl)-5H-chromeno[2,3-b]pyridin-5-yl)-2-methylpropanamido)-N-(tetrahydro-2H-pyran-4-yl)-1,3,4-thiadiazole-2-carboxamide (BMS-341).

An empirical approach to improve the microsomal stability and CYP inhibition profile of lead compounds 1a and 1b led to the identification of 5 (BMS-341) as a dissociated glucocorticoid receptor modulator. Compound 5 showed significant improvements in pharmacokinetic properties and, unlike compounds 1a-b, displayed a linear, dose-dependent pharmacokinetic profile in rats. When tested in a chronic model of adjuvant-induced arthritis in rat, the ED50 of 5 (0.9 mg/kg) was superior to that of both 1a and 1b (8 and 17 mg/kg, respectively).

Catalpol regulates cholinergic nerve system function through effect on choline acetyl-transferase not M receptor affinity.

OBJECTIVE: To explore the effect of catalpol on choline acetyl-transferase and M receptor affinity in a PC12 cell model and a rat model induced by beta-amyloid 25-35 (Aß25-35). METHODS: In PC12 cells, catalpol (10µmol/l, 100µmol/) or saline was retained in the medium and Aß25-35 (final concentration 20µmol/l) was added. Choline acetyl-transferase (ChAT) expression was determined by immunocytochemistry, ChAT activity measured by radioenzymatic assay, and M receptor (muscarinic receptor) affinity determined by (3)H-QNB binding test. In Wistar rats, Aß25-35 was injected intracerebroventricularly to establish AD model. After injection of Aß25-35, the rats were injected catalpol at 5 and 10mg/kgd(-1) intraperitoneally for the next 7 days, and saline for the control rats. ChAT expression, ChAT activity and M receptor affinity were tested. Cells and rats all were divided into four groups: Group A (control), Group B (model), Group C (catalpol low dose), and Group D (catalpol high dose). RESULTS: Compared with control, both PC12 cell and rat AD models showed decreased expression and activity of ChAT (p<0.01), but M receptor affinity remained the same (p>0.05). Compared with model group, treatment of catalpol increased expression and activity of ChAT of PC12 cell and rat AD model induced by Aß25-35, p<0.05 or p<0.01 respectively. But there was no difference of M receptor affinity among the four groups (p>0.05). M receptor affinity remained the same as concentration of catalpol increased gradually in atropine competition experiments (p>0.05). CONCLUSIONS: Catalpol could regulate the cholinergic nerve system function from its effect on ChAT and may have beneficial effect for treatment of AD, but had no effect on M receptor affinity.

Catalpol regulates function of hypothalamic-pituitary-adrenocortical-axis in an Alzheimer's disease rat model.

AIMS: To investigate the regulating effects of catalpol on the hypothalamic-pituitary- adrenocortical-axis (HPA) in an Alzheimer's disease (AD) rat model. METHODS: Healthy male Wistar Rats were selected. The AD model was generated by orthotopic injection of beta-amyloid 25-35 (Abeta25-35) into the right lateral ventricle. The animals were divided into five study groups: Catalpol at low dose (5 mg/kg), Catalpol at high dose (10 mg/kg), model control group and sham surgery control group, n = 9 respectively. The serum concentration of hydrocortisone (HYD), adrenocorticotropin (ACTH) and corticotropin releasing hormone (CRH) determined by Enzyme-Linked Immunosorbent Assay (ELISA). Structural alterations of the hypothalamus were examined by H&E stain and electron microscope. The CRH receptor 1 (CRHR1) positive neurons were detected with immunohistochemistry. RESULTS: Serum HYD level was significantly increased (p < 0.01), and both ACTH and CRH were dramatically decreased (p < 0.01) in the AD model group rats compared with normal control rats at day 7. Catalpol treatment was able to improve the hormone secretion disorder in AD model group rats compared with the model group (p < 0.01 or p < 0.05) in particular at 21 days. Structure damage of hypothalamus in the AD rat as evidenced less CRHR1 positive neurons, rough endoplasmic reticulum dilation and degranulation, and mitochondrial swelling under electron microscope. Catalpol treatment at both high and low doses was able to alleviate the structure damage of the hypothalamus in the AD rats. CONCLUSIONS: Catalpol could improve the endocrine function of the HPA and alleviate the structural damage of hypothalamus in AD rats.

[Inhibitory effect of Astragalus polysaccharides on apoptosis of pancreatic beta-cells mediated by Fas in diabetes mellitus rats].

OBJECTIVE: To observe the effects of Astragalus polysaccharides (APS) on the BG, insulin and C-peptide in serum, ultrastructure and Fas expression of pancreatic beta-cells in diabetes mellitus (DM) rats. METHODS: Thirty DM rats induced by streptozotocin (STZ) were randomly divided into three groups: DM group, APS 200 mg/kg group, APS 400 mg/kg group, another 10 normal rats were taken as the control group. The drug was given by intraperitoneal for 6 weeks. The level of BG was determined by ONE TOUCH II machine. The levels of insulin and C-peptide in serum were measured by radioimmunoassay. The expression of Fas was observed by immunohistochemistry. Moreover, the TEM was used to observe the ultrastructure of pancreatic beta-cells. RESULTS: (1) DM rats showed significant increase in BG compared with control group (P < 0.05). APS could decrease the level of FG (P < 0.05). (2) DM rats showed significant decrease in insulin and C-peptide in serum compared with control group (P < 0.05). APS has no appearance effects on the levels of them (P > 0.05). (3) The expression of Fas of beta-cells was significantly increased in DM rats, which was significantly inhibited by APS treatment. (4) It showed degenerative changes of pancreatic beta-cells ultramicroscopic structure of the DM rats, while APS treatment could significantly improve the damage. CONCLUSION: APS exerts its therapeutic effects on DM, which maybe related to the significant decreasing of the Fas expression and inhibiting the apoptosis of beta-cells.

Molecular cloning and evolutionary analysis of the GJA1 (connexin43) gene from bats (Chiroptera).

Gap junction protein connexin43 (Cx43), encoded by the GJA1 gene, is the most abundant connexin in the cardiovascular system and was reported as a crucial factor maintaining cardiac electrical conduction, as well as having a very important function in facilitating the recycling of potassium ions from hair cells in the cochlea back into the cochlear endolymph during auditory transduction processes. In mammals, bats are the only taxon possessing powered flight, placing exceptional demand on many organismal processes. To meet the demands of flying, the hearts of bats show many specialties. Moreover, ultrasonic echolocation allows bat species to orientate and often detect and locate food in darkness. In this study, we cloned the full-length coding region of GJA1 gene from 12 different species of bats and obtained orthologous sequences from other mammals. We used the maximum likelihood method to analyse the evolution of GJA1 gene in mammals and the lineage of bats. Our results showed this gene is much conserved in mammals, as well as in bats' lineage. Compared with other mammals, we found one private amino acid substitution shared by bats, which is located on the inner loop domain, as well as some species-specific amino acid substitutions. The evolution rate analyses showed the signature of purifying selection on not only different classification level lineages but also the different domains and amino acid residue sites of this gene. Also, we suggested that GJA1 gene could be used as a good molecular marker to do the phylogenetic reconstruction.

[Reactivation of hypermethylated GSTP1 promoter activity in MCF-7 cells by treatment with a component of natural drug].

OBJECTIVE: To investigate the reactivation of hypermethylated GSTP1 (glutathione S-transferase P1) promoter activity by a component of natural drug, CDP. METHODS: The recombinant plasmid of pGL3-GSTP1 pro(m) containing hypermethylated GSTP1 gene promoter was constructed and then used to transiently transfect the human breast cancer cell line MCF-7 cell. After treatment with CDP and 5-aza-C, The luciferase activity in cell lysates were assayed. RESULTS: Low promoter activities were found in hypermethylated GSTP1 promoter. The promoter activities were reactivated and in a CDP dose-dependent mode. CONCLUSION: CDP has the ability to reactivate the hypermethylated GSTP1 gene promoter activity.

[Study on effect of arsenic trioxide on adhesion and invasion of human hepatocarcinoma cells in vitro].

OBJECTIVE: To explore that the arsenic trioxide injection (ATI) has the effect in antagonizing adhesion and invasion of human hepatocarcinoma cells (HCC), and its relevant mechanism. METHODS: Human hepatocellular carcinoma cell line SMMC-7721 and the high metastatic nude mice human HCC in situ transplantation model was taken as the objects of study, the effects of ATI on the SMMC-7721 cell movement and migration, its adhesion with fibronectin (FN) and endothelial cell (EC), as well as the CD44 and MMP-2 gene protein expression in transplanted tumor of the model mice were observed by means of cell movement and migration test, cell adhesion test and immunohistochemical method. RESULTS: ATI could significantly inhibit SMMC-7721 cell movement and migration on FN, adhesion with FN and EC, also could lower CD44 and MMP-2 in cancer cells. CONCLUSION: ATI has the effects of antagonizing hepatocarcinoma cell adhesion and invasion, the mechanism may be related with the action of ATI in lowering CD44 and MMP-2 expression in cancer cells.