Metabolic Syndrome and Renal Injury

Both metabolic syndrome (MetS) and chronic kidney disease (CKD) are major global health issues. Current clinical markers used to reflect renal injury include albuminuria and estimated glomerular filtration rate (eGFR). Given the same eGFR level, urine albumin might be a better risk marker to predict progression of CKD and future development of cardiovascular diseases (CVDs). Serum Cystatin C is emerging as a new biomarker for early detection of renal injury associated with MetS and cardiovascular risk. In addition to each component, MetS per se influences the incidence and prognosis of renal injury and the odds ratios increased with the increase in the number of metabolic abnormalities. Hyperinsulinemia, activation of rennin-angiotensin-aldosterone system, increase of oxidative stress, and inflammatory cytokines are proposed to be the plausible biological link between MetS and CKD. Weight control, stick control of blood pressure, glucose, and lipids disorders may lead to lessening renal injury and even the subsequent CVD

Aspirin prevents resistin-induced endothelial dysfunction by modulating AMPK, ROS, and Akt/eNOS signaling

BackgroundResistin, an adipocytokine, plays a potential role in cardiovascular disease and may contribute to increased atherosclerotic risk by modulating the activity of endothelial cells. A growing body of evidence suggests that aspirin is a potent antioxidant. We investigated whether aspirin mitigates resistin-induced endothelial dysfunction via modulation of reactive oxygen species (ROS) generation and explored the role that AMP-activated protein kinase (AMPK), a negative regulator of nicotinamide adenine dinucleotide phosphate (NADPH) oxidase, plays in the suppressive effects of aspirin on resistin-induced endothelial dysfunction.MethodsHuman umbilical vein endothelial cells (HUVECs) were pretreated with various doses of aspirin (10-500 μg/mL) for 2 hours and then incubated with resistin (100 ng/mL) for an additional 48 hours. Fluorescence produced by the oxidation of dihydroethidium (DHE) was used to quantify the production of superoxide in situ; superoxide dismutase (SOD) and catalase activities were determined by an enzymatic assay; and protein levels of AMPK-mediated downstream signaling were investigated by Western blot.ResultsTreatment of HUVECs with resistin for 48 hours resulted in a 2.9-fold increase in superoxide production; however, pretreatment with aspirin resulted in a dose-dependent decrease in production of superoxide (10-500 μg/mL; n = 3 experiments; all P < .05). Resistin also suppressed the activity of superoxide dismutase and catalase by nearly 50%; that result, however, was not observed in HUVECs that had been pretreated with aspirin at a concentration of 500 μg/mL. The membrane translocation assay showed that the levels of NADPH oxidase subunits p47phoxand Rac-1 in membrane fractions of HUVECs were threefold to fourfold higher in cells that had been treated with resistin for 1 hour than in untreated cells; however, pretreatment with aspirin markedly inhibited resistin-induced membrane assembly of NADPH oxidase via modulating AMPK-suppressed PKC-α activation. Application of AMPKα1-specific siRNA resulted in increased activation of PKC-α and p47phox. In addition, resistin significantly decreased AMPK-mediated downstream Akt/endothelial nitric oxide synthase (eNOS)/nitric oxide (NO) signaling and induced the phosphorylation of p38 mitogen-activated protein kinases, which in turn activated NF-κB-mediated inflammatory responses such as the release of interleukin (IL)-6 and IL-8, the overexpression of adhesion molecules, and stimulation of monocytic THP-1 cell attachment to HUVECs (2.5-fold vs control; n = 3 experiments). Furthermore, resistin downregulated eNOS and upregulated inducible NO synthase (iNOS) expression, thereby augmenting the formation of NO and protein nitrosylation. Pretreatment with aspirin, however, exerted significant cytoprotective effects in a dose-dependent manner (P < .05).ConclusionsOur findings suggest a direct connection between adipocytokines and endothelial dysfunction and provide further insight into the protective effects of aspirin in obese individuals with endothelial dysfunction.Clinical RelevanceResistin has been reported to involve in the inflammatory process, which is a common feature in metabolic syndrome, insulin resistance status, and vascular diseases. This study underscores the potential clinical benefits and application of aspirin in prevention of obese-associated vascular dysfunction

Risk Factors for Recurrent Hypoglycemia in Hospitalized Diabetic Patients Admitted for Severe Hypoglycemia

Purpose: Severe hypoglycemia can result in neural damage, impaired cognitive function, coma, seizures, or death. The decision to admit diabetic patients after initial treatment in the emergency department remains unclear. Our purpose is to identify risk factors for developing recurrent hypoglycemia in diabetic patients admitted for severe hypoglycemia. Materials and Methods: We reviewed the records of 233 subjects (92 males, 141 females; mean age, 74.1 ± 9.8 years) with type 2 diabetes treated at a tertiary care teaching hospital and hospitalized for severe hypoglycemia. Results: Seventy-four (31.8%) patients were categorized with recurrent hypoglycemia and 159 (68.2%) with non-recurrent. Multivariate logistic regression analysis revealed that patients with loss of a recent meal, coronary artery disease, infection, and poor renal function (lower estimated glomerular filtration rate) were at risk for recurrent hypoglycemia. The use of calcium-channel blockers appeared to be a protective factor for the development of recurrent hypoglycemia. Conclusion: There may be a subset of patients with severe hypoglycemia and certain risk factors for recurrent hypoglycemia that should be admitted

Impact of Clinical Characteristics of Individual Metabolic Syndrome on the Severity of Insulin Resistance in Chinese Adults

The impact the metabolic syndrome (MetS) components on the severity of insulin resistance (IR) has not been reported. We enrolled 564 subjects with MetS and they were divided into quartiles according to the level of each component; and an insulin suppression test was performed to measure IR. In males, steady state plasma glucose (SSPG) levels in the highest quartiles, corresponding to body mass index (BMI) and fasting plasma glucose (FPG), were higher than the other three quartiles and the highest quartiles, corresponding to the diastolic blood pressure and triglycerides, were higher than in the lowest two quartiles. In females, SSPG levels in the highest quartiles, corresponding to the BMI and triglycerides, were higher than in all other quartiles. No significant differences existed between genders, other than the mean SSPG levels in males were greater in the highest quartile corresponding to BMI than that in the highest quartile corresponding to HDL-cholesterol levels. The factor analysis identified two underlying factors (IR and blood pressure factors) among the MetS variables. The clustering of the SSPG, BMI, triglyceride and HDL-cholesterol was noted. Our data suggest that adiposity, higher FPG and triglyceride levels have stronger correlation with IR and subjects with the highest BMI have the highest IR

Diabetes-Specific Nutrition Algorithm: A Transcultural Program to Optimize Diabetes and Prediabetes Care

Type 2 diabetes (T2D) and prediabetes have a major global impact through high disease prevalence, significant downstream pathophysiologic effects, and enormous financial liabilities. To mitigate this disease burden, interventions of proven effectiveness must be used. Evidence shows that nutrition therapy improves glycemic control and reduces the risks of diabetes and its complications. Accordingly, diabetes-specific nutrition therapy should be incorporated into comprehensive patient management programs. Evidence-based recommendations for healthy lifestyles that include healthy eating can be found in clinical practice guidelines (CPGs) from professional medical organizations. To enable broad implementation of these guidelines, recommendations must be reconstructed to account for cultural differences in lifestyle, food availability, and genetic factors. To begin, published CPGs and relevant medical literature were reviewed and evidence ratings applied according to established protocols for guidelines. From this information, an algorithm for the nutritional management of people with T2D and prediabetes was created. Subsequently, algorithm nodes were populated with transcultural attributes to guide decisions. The resultant transcultural diabetes-specific nutrition algorithm (tDNA) was simplified and optimized for global implementation and validation according to current standards for CPG development and cultural adaptation. Thus, the tDNA is a tool to facilitate the delivery of nutrition therapy to patients with T2D and prediabetes in a variety of cultures and geographic locations. It is anticipated that this novel approach can reduce the burden of diabetes, improve quality of life, and save lives. The specific Southeast Asian and Asian Indian tDNA versions can be found in companion articles in this issue of Current Diabetes Reports

Serum Renalase Levels Are Predicted by Brain-Derived Neurotrophic Factor and Associated with Cardiovascular Events and Mortality after Percutaneous Coronary Intervention

Circulating brain-derived neurotrophic factor (BDNF) predicts survival rate in patients with coronary artery disease (CAD). We examined the relationship between BDNF and renalase before and after percutaneous coronary intervention (PCI) and the role of renalase in patients with CAD. Serum BDNF and renalase levels were determined using blood samples collected before and after PCI. Incident myocardial infarction, stroke, and mortality were followed up longitudinally. A total of 152 patients completed the assessment. BDNF levels were not significantly changed after PCI compared to baseline levels (24.7 &#177; 11.0 vs. 23.5 &#177; 8.3 ng/mL, p = 0.175), although renalase levels were significantly reduced (47.5 &#177; 17.3 vs. 35.9 &#177; 11.3 ng/mL, p &lt; 0.001). BDNF level before PCI was an independent predictor of reduction in renalase (95% confidence interval (CI): &#8722;1.371 to &#8722;0.319). During a median 4.1 years of follow-up, patients with serum renalase levels of &#8805;35 ng/mL had a higher risk of myocardial infarction, stroke, and death than those with renalase of &lt;35 ng/mL (hazard ratio = 5.636, 95% CI: 1.444&#8315;21.998). In conclusion, our results show that serum BDNF levels before PCI were inversely correlated with the percentage change in renalase levels after PCI. Nevertheless, post-PCI renalase level was a strong predictor for myocardial infarction, stroke, and death