BackgroundThe association between sarcopenia and cardiovascular disease (CVD) in elderly people has not been adequately assessed. The aim of this study was to investigate whether CVD is more prevalent in subjects with sarcopenia independent of other well-established cardiovascular risk factors in older Korean adults.MethodThis study utilized the representative Korean population data from the Korea National Health and Nutrition Examination Survey (KNHANES) which was conducted in 2009. Subjects older than 65 years of age with appendicular skeletal muscle mass (ASM) determined by dual energy X-ray absorptiometry were selected. The prevalence of sarcopenia in the older Korean adults was investigated, and it was determined whether sarcopenia is associated with CVD independent of other well-known risk factors.Results1,578 subjects aged 65 years and older with the data for ASM were selected, and the overall prevalence of sarcopenia was 30.3% in men and 29.3% in women. Most of the risk factors for CVD such as age, waist circumference, body mass index, fasting plasma glucose and total cholesterol showed significant negative correlations with the ratio between appendicular skeletal muscle mass and body weight. Multiple logistic regression analysis demonstrated that sarcopenia was associated with CVD independent of other well-documented risk factors, renal function and medications (OR, 1.768; 95% CI, 1.075–2.909, P = 0.025).ConclusionsSarcopenia was associated with the presence of CVD independent of other cardiovascular risk factors after adjusting renal function and medications.

Epigallocatechin-3-gallate (EGCG) is the main polyphenolic constituent in green tea and is believed to function as an antioxidant. However, increasing evidence indicates that EGCG produces reactive oxygen species (ROS) and subsequent cell death. In this study, we investigated the prooxidative effects of EGCG on the HIT-T15 pancreatic beta cell line. Dose-dependent cell viability was monitored with the cell counting kit-8 assay, while the induction of apoptosis was analyzed by a cell death ELISA kit and comet assay. Extracellular H(2)O(2) was determined using the Amplex Red Hydrogen Peroxide Assay Kit. Intracellular oxidative stress was measured by fluorometric analysis of 2',7'-dichlorofluorescin (DCFH) oxidation using DCFH diacetate (DA) as the probe. Treatment with EGCG (5-100 microM) decreased the viability of pancreatic beta cells, caused concomitant increases in apoptotic cell death, and increased the production of H(2)O(2) and ROS. Catalase, the iron-chelating agent diethylenetriaminepentaacetic acid, and the Fe(II)-specific chelator o-phenanthroline all suppressed the effects of EGCG, indicating the involvement of both H(2)O(2) and Fe(II) in the mechanism of action of EGCG. The antioxidant N-acetyl-cysteine and alpha-lipoic acid also suppressed the effects of EGCG. Furthermore, EGCG did not scavenge exogenous H(2)O(2), but rather, it synergistically increased H(2)O(2)-induced oxidative cell damage in pancreatic beta cells. Together, these findings suggest that in the HIT-T15 pancreatic beta cell line, EGCG mediated the generation of H(2)O(2), triggering Fe(II)-dependent formation of a highly toxic radical that in turn induced oxidative cell damage.

During the progression of Type 2 diabetes, glucose toxicity is likely to contribute importantly to progressive beta cell failure. Oxidative stress is an important aspect of glucose toxicity in pancreatic beta cells, and reducing sugars, such as 2-deoxy-D-ribose (dRib), produce reactive oxygen species. Furthermore, many of the biological properties of flavonoids are likely to be related to their antioxidant and free-radical scavenging abilities. Accordingly, in the present study, we investigated whether kaempferol (a flavonol) protects beta cells from dRib-induced oxidative damage. HIT-T15 cells were cultured with various concentrations of dRib for 24h. Cell survivals, amounts of reactive oxygen species (ROS) generated, apoptosis, and lipid peroxidation were measured. dRib was found to dose-dependently reduce cell survival and to markedly increase intracellular ROS levels, apoptosis, and lipid peroxidation. However, kaempferol (10 microM) suppressed dRib (20 mM) induced intracellular ROS, apoptosis, and lipid peroxidation. So, we demonstrate that kaempferol reduces dRib-mediated beta cell damage interfering with ROS metabolism and protective effects against lipid peroxidation. Our findings indicate that kaempferol protects HIT-T15 cells from dRib-induced associated oxidative damage.

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BackgroundWe developed for the first time a smartphone application designed for diabetes self-management in Korea and registered a patent for the relevant algorithm. We also investigated the user satisfaction with the application and the change in diabetes related self-care activities after using the application.MethodsWe conducted a questionnaire survey on volunteers with diabetes who were using the application. Ninety subjects responded to the questionnaire between June 2012 and March 2013. A modified version of the Summary of Diabetes Self-Care Activities (SDSCA) was used in this study.ResultsThe survey results exhibited a mean subject age of 44.0 years old, and males accounted for 78.9% of the subjects. Fifty percent of the subjects had diabetes for less than 3 years. The majority of respondents experienced positive changes in their clinical course after using the application (83.1%) and were satisfied with the structure and completeness of the application (86.7%). Additionally, the respondents' answers indicated that the application was easy to use (96.7%) and recommendable to others (97.7%) and that they would continue using the application to manage their diabetes (96.7%). After using the Diabetes Notepad application, diabetes related self-care activities assessed by SDSCA displayed statistically significant improvements (P<0.05), except for the number of days of drinking.ConclusionThis smartphone-based application can be a useful tool leading to positive changes in diabetes related self-care activities and increase user satisfaction.

Glucagon-like peptide-1 (GLP-1) is a potent insulinotrophic hormone, which makes GLP-1 an attractive candidate for the treatment of type 2 diabetes. However, the short plasma half-life of the active forms of GLP-1 poses an obstacle to the sustained delivery of this peptide. In this study, we evaluated the effect of GLP-1 gene delivery both in vitro and in vivo using a new plasmid constructed with a modified GLP-1 (7-37) cDNA. This cDNA contains a furin cleavage site between the start codon and the GLP-1 coding region. The expression of the GLP-1 gene was driven by a chicken beta-actin promoter (pbetaGLP1). The level of the GLP-1 mRNA was evaluated by RT-PCR 24 h after transfection. The in vitro results showed a dose-dependent expression of GLP-1. Coculture assay of the GLP-1 plasmid-transfected cells with isolated rat islet cells demonstrated that GLP-1 increased insulin secretion by twofold, compared to controls during a hyperglycemic challenge. A single injection of polyethyleneimine/pbetaGLP1 complex into ZDF rats resulted in increasing insulin secretion and decreasing blood glucose level that was maintained for 2 weeks. This GLP-1 gene delivery system may provide an effective and safe treatment modality for type 2 diabetes.

With strong basal promoter activity and induction under hypoxia, pRTP801-VEGF may be useful for gene therapy for ischemic disease.

Several environmental contaminants have been linked to the development of diabetes and increased diabetes‑associated mortality. Perfluorooctanoic acid (PFOA) is a widely used perfluoroalkane found in surfactants and lubricants, and in processing aids used in the production of polymers. Furthermore, PFOA has been detected in humans, wildlife and the environment. The present study investigated the toxic effects of PFOA on rat pancreatic β‑cell‑derived RIN‑m5F cells. Cell viability, apoptosis, reactive oxygen and nitrogen species, cytokine release and mitochondrial parameters, including membrane potential collapse, reduced adenosine triphosphate levels, cardiolipin peroxidation and cytochrome c release were assessed. PFOA significantly decreased RIN‑m5F cell viability and increased apoptosis. Exposure to PFOA increased the formation of reactive oxygen species, mitochondrial superoxide, nitric oxide and proinflammatory cytokines. Furthermore, PFOA induced mitochondrial membrane potential collapse and reduced adenosine triphosphate levels, cardiolipin peroxidation and cytochrome c release. These results indicate that PFOA is associated with the induction of apoptosis in RIN-m5F cells, and induces cytotoxicity via increased oxidative stress and mitochondrial dysfunction.