6-gingerol ameliorates weight gain and insulin resistance in metabolic syndrome rats by regulating adipocytokines.

Metabolic syndrome (MetS) can lead to increase of insulin resistance (IR) and visceral adipose tissue production of adipocytokines. 6-gingerol is known to have antioxidant and anti-inflammatory activities. Aim of this study is to investigate the effects of 6-gingerol on high-fat high-fructose (HFHF) diet-induced weight gain and IR in rats through modulation of adipocytokines. To induce MetS, male Sprague-Dawley rats were fed with a HFHF diet for 16 weeks and at Week 8, single-dose low-dose streptozotocin (22 mg/kg) were intraperitoneally injected. After 8 weeks of HFHF diet feeding, the rats were treated orally with 6-gingerol (50, 100, and 200 mg/kg/day) once daily for 8 weeks. At the end of the study, all animals were terminated, serum, liver, and visceral adipose tissues were harvested for biochemical analysis including the measurements of total cholesterol, triglycerides, HDL-cholesterol, fasting plasma glucose, insulin, leptin, adiponectin, proinflammatory cytokines (TNF-α and IL-6) and liver and adipose tissue histopathology. Biochemical parameters namely serum total cholesterol (243.7 ± 127.6 vs 72.6 ± 3 mg/dL), triglycerides (469.2 ± 164.9 vs 49.3 ± 6.3 mg/dL), fasting plasma glucose (334 ± 49.5 vs 121 ± 8.5 mg/dL), HOMA-IR (0.70 ± 0.24 vs 0.32 ± 0.06), and leptin (6.19 ± 1.24 vs 3.45 ± 0.33 ng/mL) were significantly enhanced, whereas HDL-cholesterol (26.2 ± 5.2 vs 27.9 ± 1.1 mg/dL) and adiponectin level (14.4 ± 5.5 vs 52.8 ± 10.7 ng/mL) were lowered in MetS vs normal control. Moreover, MetS were marked a significant increase in body weight and proinflammatory cytokines. Treatment with 6-gingerol dose-dependently restored all of those alterations towards normal values as well as the accumulation of lipid in liver and adipose tissues. These findings demonstrate that 6-gingerol, in a dose-dependent mode, showed capability of improving weight gain and IR in MetS rats through modulation of adipocytokines.

Apela/Elabela/Toddler: New perspectives in molecular mechanism of heart failure.

Background. Despite significant therapeutic advances, heart failure (HF) remains unacceptably high in morbidity and mortality. Additionally, its high-care and costs make HF a deadly and costly disease. First reported independently by two group of researchers, Apela/Elabela/Toddler (ELA) is the second endogenous apelin-receptor ligand discovered which is encoded from a previously classified non-coding gene, and has emerged as a key signalling-pathway in the cardiovascular system. Aims. To explore and summarise the biological effects and diagnostic potential of ELA as a new biomarker for heart failure. Results. ELA (prepro-ELA 54 AA) is a molecule with three isoforms (ELA 11,16 and 32), recently identified as the second endogenous ligand to APJ-receptor and functions to mediate early cardiac development during zebrafish embryogenesis by inducing cardiogenesis, vasculogenesis and bone formation. In adults, it enhances cardiac contractility, promotes vasodilatory effects, mediates fluid homeostasis, reduces food intake, limits kidney dysfunction and exerts anti-atherosclerotic as well as anti-oxidative properties. Conclusion. These results show that ELA, an endogenous agonist of the APJ-receptor exerts cardiovascular effects comparable and potentially more potent than apelin and is found to be downregulated in experimental models and humans with heart failure.

Elevated Levels of Apelin-36 in Heart Failure Due to Chronic Systemic Hypoxia.

Apelin is a novel adipokine identified as an endogenous ligand of the specific orphan receptor APJ. Among the various isoforms of apelin, an increase in the apelin-36 plasma level has been associated with oxidative stress, and this isoform has various biological effects, such as positive inotropic, vasodilatory, and antiatherosclerotic effects. Therefore, apelin-36 may be used as a biomarker of heart failure (HF). Advances in the understanding of the molecular mechanisms underlying HF cannot be achieved without the use of animal models. However, it is unclear whether chronic systemic hypoxia can cause HF in rats. The present study aimed to determine whether chronic systemic hypoxia can cause HF in rats and whether apelin-36 can be used as a biomarker of HF. The study included Sprague-Dawley rats. The rats were randomly divided into seven groups ( n = 4). One of the groups was a control group, and the six other groups were exposed to hypoxia (8% O2) for different durations (6 hours, 1 day, 3 days, 5 days, 7 days, and 14 days). The exposure groups showed ventricular hypertrophy accompanied by myocardial structural damage, which indicated ventricular remodeling. In addition, the exposure groups showed elevated apelin-36 plasma levels and signs of oxidative stress. Moreover, gel electrophoresis of heart tissue showed five bands that corresponded to apelin isotypes, including apelin-36. In an experimental rat HF model with chronic systemic hypoxia, apelin-36 was elevated along with oxidative stress. Apelin-36 along with oxidative stress may serve as a biomarker of HF in this model.

Risk and Benefits of Statins in Glucose Control Management of Type II Diabetes.

Worldwide statins are considered to be the first-line pharmacological treatment for dyslipidemia and reducing the risk of coronary heart disease. However, recently various studies have shown its adverse effect on glucose control among diabetic patients and the U.S. Food and Drug Administration have revised statin drug labels to include information that increases in fasting serum glucose and glycated hemoglobin levels have been reported. This systematic review objective is to evaluate the risks and benefits of statins in glucose control management of type 2 diabetes patients based on the 44 published journal articles included and obtained through MEDLINE full text, PubMed, Science Direct, Pro Quest, SAGE, Taylor and Francis Online, Google Scholar, High Wire, and Elsevier Clinical Key. Statins were found to affect glucose control through several ways, namely, by affecting insulin production and secretion by ß-pancreatic cells, insulin resistance, insulin uptake by the muscles and adipocytes and production of adipokines. Current evidence available shows that most of the statins give unfavorable side effects with regards to glucose control among diabetic patients. A dose-dependent and time-dependent effect was also observed in some statins which may be present among other statins as well.

Structural and morphological changes in rat ventricular myocardium induced by chronic systemic hypoxi.

AIM: to explore the effects of chronic systemic hypoxia on myocardial structure and morphology. In addition, the goal of present study is to develop a hypoxia-induced heart failure model in rats. METHODS: Sprague-Dawley male rats, weighing 220-250 g at the time of recruitment were randomly allocated into 7 groups (n = 4 per group), the control normoxia group was exposed to room air, while the hypoxia groups were caged in a plexiglas hypoxic chamber (8% O2 and 92% N2) for 28 days. Structural and morphological changes of ventricular myocardium were determined at day 28, while blood gas parameters were measured at day 1, 3, 7, 14, 21, and 28. RESULTS: histopathologic and morphologic evaluation showed massive hypertrophy accompanied by damage of the intercalated disk (ID) structure, angiogenesis, necrosis, fibrosis, and apoptosis as a hallmark of ventricular remodeling. At the end of treatment, there were increases of LV (2.79 vs 3.71) and RV (1.72 vs 2.54) wall thicknesses, and also in hypertrophy index (from 3.19 to 5.74). Blood gas analysis revealed metabolic acidosis compensated by respiratory alkalosis. There was an observed decrease of blood gas parameters in hypoxia group compared to control group: PO2 (24.7 vs 96.4 mm Hg), PCO2 (18.2 vs 40.4 mm Hg), O2 saturation (25.5 vs 94.1 %), and HCO3 (10.1 vs 23.4 mmol/L). On the other hand an increase in hemoglobin level (221.5 vs 120.3 g/L), haematocrit level (68.6 vs 45.2 %), and red blood cell count (10.4 vs 6.9 µL/1000) could be observed. CONCLUSION: our data clearly show that chronic systemic hypoxia causes massive ventricular hypertrophy accompanied by severe structural and morphological impairment of ventricular myocardium, which eventually results in cardiac failure.

Expression of B-type natriuretic peptide-45 (BNP-45) gene in the ventricular myocardial induced by systemic chronic hypoxia.

AIM: To investigate the expression of B-type natriuretic peptide-45 (BNP-45) gene which was induced by systemic chronic hypoxia, and whether these changes would be different from BNP-45 protein in the plasma and its mRNA in the ventricular myocardial. This study also aimed to test the hypothesis that systemic chronic hypoxia may cause heart failure. METHODS: Although clinical use of BNP as a biomarker in heart failure is increasing, the specificity of BNP for heart failure is not robust, suggesting that other mechanisms beyond simple ventricular stretch stimulate BNP release. Plasma BNP levels were markedly increased in patients with coronary artery disease but without concomitant left ventricular dysfunction. Thus, elevated BNP levels do not necessarily reflect heart failure but may also result from cardiac ischemia. Sprague-Dawley male rats, weighing 220-250 g at the time of recruitment were randomly divided into 7 groups (n = 4 per group), the control normoxia group was exposed to room air, while the hypoxia group were caged in a plexiglass hypoxic chamber (8%O2 and 92% N2) for 1, 3, 7, 14, 21, and 28 days, respectively. RESULTS: Our data clearly showed that plasma BNP-45 and ventricular BNP-45 mRNA concentration were markedly increased which reached its peak on day 21 after treatment. CONCLUSION: Regulation of BNP-45 gene expression occurred at transcription as well as post-transcription level. Systemic chronic hypoxia could result in heart failure, especially when the hypoxia is severe and prolonged.