Anti-Diabetic Effect of Cotreatment with Quercetin and Resveratrol in Streptozotocin-Induced Diabetic Rats

Quercetin and resveratrol are known to have beneficial effects on the diabetes and diabetic complication, however, the effects of combined treatment of these compounds on diabetes are not fully revealed. Therefore, the present study was designed to investigate the combined antidiabetic action of quercetin (QE) and resveratrol (RS) in streptozotocin (STZ)-induced diabetic rats. To test the effects of co-treated with these compounds on diabetes, serum glucose, insulin, lipid profiles, oxidative stress biomarkers, and ions were determined. Additionally, the activities of hepatic glucose metabolic enzymes and histological analyses of pancreatic tissues were evaluated. 50 male Sprague-Dawley rats were divided into five groups; normal control, 50 mg/kg STZ-induced diabetic, and three (30 mg/kg QE, 10 mg/kg RS, and combined) compound-treated diabetic groups. The elevated serum blood glucose levels, insulin levels, and dyslipidemia in diabetic rats were significantly improved by QE, RS, and combined treatments. Oxidative stress and tissue injury biomarkers were dramatically inhibited by these compounds. They also shown to improve the hematological parameters which were shown to the hyperlactatemia and ketoacidosis as main causes of diabetic complications. The compounds treatment maintained the activities of hepatic glucose metabolic enzymes and structure of pancreatic β-cells from the diabetes, and it is noteworthy that cotreatment with QE and RS showed the most preventive effect on the diabetic rats. Therefore, our study suggests that cotreatment with QE and RS has beneficial effects against diabetes. We further suggest that cotreatment with QE and RS has the potential for use as an alternative therapeutic strategy for diabetes.

Hepatoprotective effects of Nigella sativa seed extract against acetaminophen-induced oxidative stress

OBJECTIVE@#To investigate the protective effects of Nigella sativa seed extract (NSSE) against acetaminophen (APAP)-induced hepatotoxicity in TIB-73 cells and rats.@*METHODS@#Toxicity in TIB-73 cells was induced with 10 μmol/L APAP and the protective effects of NSSE were evaluated at 25, 50, 75, 100 μg/mL. For in vivo examination, a total of 30 rats were equally divided into five experimental groups; normal control (vehicle), APAP (800 mg/kg body weight single IP injection) as a hepatotoxic control, and three APAP and NS pretreated (2 weeks) groups (APAP + NSSE 100 mg; APAP + NSSE 300 mg and APAP + NSSE 900 mg/kg).@*RESULTS@#TIB-73 cell viability was drastically decreased by (49.0 ± 1.9)% after the 10 μmol/LAPAP treatment, which also increased reactive oxygen species production. Co-treatment with NSSE at 25, 50, 75, and 100 μg/mL significantly improved cell viability and suppressed reactive oxygen species generation. In vivo, the APAP induced alterations in blood lactate levels, pH, anionic gap, and ion levels (HCO3(-), Mg(2+) and K(+)), which tended to normalize with the NSSE pretreatment. The NSSE also significantly decreased elevated serum levels of alanine aminotransferase, aspartate aminotransferase, lactate dehydrogenase, and alkaline phosphatase induced by APAP, which correlated with decreased levels of hepatic lipid peroxidation (malondialdehyde), increased superoxide dismutase levels, and reduced glutathione concentrations. Improved hepatic histology was also found in the treatment groups other than APAP group.@*CONCLUSIONS@#The in vitro and in vivo findings of this study demonstrated that the NSSE has protective effects against APAP-induced hepatotoxicity and metabolic disturbances by improving antioxidant activities and suppressing both lipid peroxidation and ROS generation.

Hepatoprotective effects of Nigella sativa seed extract against acetaminophen-induced oxidative stress

Objective: To investigate the protective effects of Nigella sativa seed extract (NSSE) against acetaminophen (APAP)-induced hepatotoxicity in TIB-73 cells and rats. Methods: Toxicity in TIB-73 cells was induced with 10 μmol/L APAP and the protective effects of NSSE were evaluated at 25, 50, 75, 100 μg/mL. For in vivo examination, a total of 30 rats were equally divided into five experimental groups; normal control (vehicle), APAP (800 mg/kg body weight single IP injection) as a hepatotoxic control, and three APAP and NS pretreated (2 weeks) groups (APAP + NSSE 100 mg; APAP + NSSE 300 mg and APAP + NSSE 900 mg/kg). Results: TIB-73 cell viability was drastically decreased by (49.0 ± 1.9)% after the 10 μmol/LAPAP treatment, which also increased reactive oxygen species production. Co-treatment with NSSE at 25, 50, 75, and 100 μg/mL significantly improved cell viability and suppressed reactive oxygen species generation. In vivo, the APAP induced alterations in blood lactate levels, pH, anionic gap, and ion levels (HCO

Korean red ginseng prevents ethanol-induced hepatotoxicity in isolated perfused rat liver / 대한수의학회지

Alcohol abuse and its medical and social consequences are a major health problem in many areas of the world. Korean red ginseng (KRG) has been traditionally used for the treatment of liver disease. This study was conducted to evaluate the hepatoprotective effects of KRG against hepatotoxicity in Sprague-Dawley rats treated with ethanol (EtOH). Administration of EtOH for 20 days induced significant changes in serum biochemical parameters (aspartate aminotransferase, alanine transaminase, and glucose) accompanied by histological changes in the liver tissue. Treatment with KRG prior to administration of EtOH inhibited the EtOH-induced biochemical and histological changes of the liver. In perfused rat livers, administration of EtOH caused an increase in lactate dehydrogenase (LDH) release into the perfusate and activated the pro-apoptotic Bax protein but inhibited the anti-apoptotic Bcl-2 protein. Pretreatment with KRG prior to administration of EtOH decreased the EtOH-induced LDH release and inhibition of Bcl-2 protein. These results suggest that KRG exerts anti-apoptotic effects and alleviated EtOH-induced liver injury in rats.

Morphometric Studies in the Leydig Cell of Hemicastrated Rats / 체질인류학회지

The present study was conducted to investigate the influence of hemicastration and age at hemicastraion on the subsequent Leydig cell morphology and function of male rats. Sprague Dawley rats were left intact or hemicastrated at 20, 30, 40, 50, or 60 days of age (n=18 rats per group). At 100 days of age, all rats were sacrificed. Testes were fixed by whole body perfusion using a fixative containing 2.5% glutaraldehyde in cacodylate buffer, processed and embedded in Epon-araldite. Using 1 micrometer sections stained with methylene blue, qualitative and quantitative morphological studies were performed. Testis incubations were used to determine lutenizing hormone (LH; 100 ng/mL) stimulated testosterone secretory capacity per testis in vitro. Testosterone levels in the incubation medium, and testosterone and LH levels in serum of these six groups of rats were determined by radioimmunoassay. Body and testis weights were not changed by hemicastration between experimental and control groups. Volume density of seminiferous tubules, interstitium, and Leydig cells was not significantly affected by hemicastration. Absolute volume of seminiferous and interstitium was significantly increased in unilaterally castrated rats at 20, 30 and 40 days of age compared to control. Significant increases in the total number of Leydig cells per testis occurred in rats hemicastrated at 20, 30, 40 and 50 days of age compared to control. A significant increase in average volume of a Leydig cell was noted in the hemicastrated rats at 30 and 40 days compared to intact rats of the same age but was significantly decreased at 60 days of age. Serum testosterone levels and LH-stimulated testosterone production per testis were significantly (P<0.05) increased in the hemicastrated rats at 30 and 40 days. In summary, when rats were unilaterally castrated at 20, 30, 40, 50, and 60 days of age, those rats hemicastrated at 30 and 40 days showed compensatory hypertrophy/hypersecretion of Leydig cells when killed at 100 days of age. Especially, these data suggested that compensatory hypertrophy/hypersecretion of Leydig cells in rats hemicastrated around the time of puberty occurs in the remaining testis.

pH-dependent modulation of intracellular free magnesium ions with ionselective electrodes in papillary muscle of guinea pig

A change in pH can alter the intracellular concentration of electrolytes such as intracellular Ca2+ and Na+ ([Na+]i) that are important for the cardiac function. For the determination of the role of pH in the cardiac magnesium homeostasis, the intracellular Mg2+ concentration ([Mg2+]i), membrane potential and contraction in the papillary muscle of guinea pigs using ion-selective electrodes changing extracellular pH ([pH]o) or intracellular pH ([pH]i) were measured in this study. A high CO2-induced low [pH]o causes a significant increase in the [Mg2+]i and [Na+]i, which was accompanied by a decrease in the membrane potential and twitch force. The high [pH]o had the opposite effect. These effects were reversible in both the beating and quiescent muscles. The low [pH]o-induced increase in [Mg2+]i occurred in the absence of [Mg2+]o. The [Mg2+]i was increased by the low [pH]i induced by propionate. The [Mg2+]i was increased by the low [pH]i induced by NH4Cl-prepulse and decreased by the recovery of [pH]i induced by the removal of NH4Cl. These results suggest that the pH can modulate [Mg2+]i with a reverse relationship in heart, probably by affecting the intracellular Mg2+ homeostasis, but not by Mg2+ transport across the sarcolemma.

The Effect of Myocardial Infarction on the Reproductive Function in Adult Male Rats / 체질인류학회지

The present study was to investigate in more detail the changes of reproductive function in the male rat following myocardial infarction (MI). Ligation of the left coronary artery was performed in male Sprague-Dawley male rats at 60 days of age. Control rats were obtained sham-operated animals. MI rats were sacrificed at 1, 3, 5, 7, 14, and 30 day after ligation of left anterior descending coronary artery. Control rats were sacrificed on 30 day after thoracotomy. Myocardial infarct size was assessed by planimetry and perimetry. Testes of rats were fixed by whole body perfusion using a fixative containing 2.5% glutaraldehyde in cacodylate buffer, processed and embedded in Epon-araldite. Using 1 micro sections stained with methylene blue-azure II, qualitative and quantitative (stereological) morphological studies were performed. Testosterone levels in the incubation medium of luteinizing hormone-stimulated (100 ng/mL) testosterone secretion per testis in vitro, and in serum were determined by radioimmunoassay. Sperm production was measured by routine technique. Mean infarct size was 29.5~33.5% of the left ventricle after coronary occlusion in experimental groups. No changes were observed in testis volume, absolute volume of Leydig cell, Leydig cell size, and number of Leydig cell per testis in MI rats compared to sham-operated animals. Serum testosterone, LH-stimulated testicular testosterone production, and daily sperm production in MI rats were not significantly different (P>0.05) from sham-operated animals. These results demonstrate that under the experimental conditions employed here, experimental chronic myocardial infarction does not exert adverse effects on the reproductive function of male rats.

Effects of histamine H|2-receptor stimulation on Mg2+ efflux in perfused guinea pig heart

Mg2+ is an important regulator of many cardiac functions. However, regulation of intracellular Mg2+ activity in the heart is not well characterized. To assess the effect of histamine H2-receptor stimulation on intracellular Mg2+ regulation, changes in extracellular Mg2+ concentration were examined under a variety of conditions in perfused guinea pig hearts. Mg2+ in the cardiac perfusate was measured by atomic absorbance spectrophotometry. The histamine (10(-6) M induced a marked Mg2+ efflux from the heart. The H2-receptor antagonists, cimetidine (10(-5) M), ranitidine (10(-5) ND, but not a H1-receptor antagonist, diphenhydramine (3 X 10(-6) M), completely blocked the histamine-induced Mg2+ efflux. The Mg2+ efflux could also be induced by forskolin (3 X 10(-6) M), 8-Cl-cAMP (2 X 10(-4) M), permeable cAMP analogue, or dimaprit, (10(-5) M). However, the carbachol (10(-5) M) considerably decreased the efflux of Mg2+. In the presence of papaverine (10(-5) M), a phosphodiesterase inhibitor, dimaprit-induced Mg2+ efflux was potentiated. These results suggest that a significant Mg2+ efflux from perfused guinea pig heart by histamine can be induced by the histamine H2-receptor stimulation and it is suggested that cytosolic cAMP may be linked.

Regulation of Mg2+ release in guinea pig heart and isolated ventricular myocytes by alpha1-adrenergic stimulation

Mg2+ is the fourth most abundant cation in cellular organisms. Although the biological chemistry and the physiological roles of the magnesium ion were well known, the regulation of intracellular Mg2+ in mammalian cells is not fully understood. More recently, however, the mechanism of Mg2+ mobilization by hormonal stimulation has been investigated in hearts and in myocytes. In this work we have investigated the regulation mechanism responsible for the Mg2+ mobilization induced by alpha1-adrenoceptor stimulation in perfused guinea pig hearts or isolated myocytes. The Mg2+ content of the perfusate or the supernatant was measured by atomic absorbance spectrophotometry. The elimination of Mg2+ in the medium increased the force of contraction of right ventricular papillary muscles. Phenylephrine also enhanced the force of contraction in the presence of Mg2+/-free medium. alpha1-Agonists such as phenylephrine were found to induce Mg2+ efflux in both perfused hearts or myocytes. This was blocked by prazosin, a alpha1-adrenoceptor antagonist. Mg2+ efflux by phenylephrine was amplified by Na+ channel blockers, an increase in extracellular Ca2+ or a decrease in extracellular Na+. By contrast, the Mg2+ influx was induced by verapamil, nifedipine, ryanodine, lidocaine or tetrodotoxin in perfused hearts, but not in myocytes. W7, a Ca2+/calmodulin antagonist, completely blocked the phenylephrine-, A23187-, veratridine-, Ca2+/-induced Mg2+ efflux in perfused hearts or isolated myocytes. In addition, Mg2+ efflux was induced by W7 in myocytes but not in perfused heart. In conclusion, An increase in Mg2+ efflux by alpha1-adrenoceptor stimulation in hearts can be through IP3 and Ca2+/-calmodulin dependent mechanism.