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The brain, in particular the hypothalamus, plays a role in regulating glucose homeostasis; however, it remains unclear whether this organ is causally and etiologically involved in the development of diabetes. Here, we found that hypothalamic transforming growth factor-β (TGF-β) production is excessive under conditions of not only obesity but also aging, which are two general etiological factors of type 2 diabetes. Pharmacological and genetic approaches revealed that central TGF-β excess caused hyperglycemia and glucose intolerance independent of a change in body weight. Further, using cell-specific genetic analyses in vivo, we found that astrocytes and proopiomelanocortin neurons are responsible for the production and prodiabetic effect of central TGF- β, respectively. Mechanistically, TGF-β excess induced a hypothalamic RNA stress response, resulting in accelerated mRNA decay of IκBα, an inhibitor of proinflammatory nuclear factor-κB. These results reveal an atypical, mRNA metabolism-driven hypothalamic nuclear factor-κB activation, a mechanism that links obesity as well as aging to hypothalamic inflammation and ultimately to type 2 diabetes., Type 2 diabetes (T2D), one of most prevalent chronic diseases in developed societies, is initiated by the induction of glucose intolerance, a prediabetic state of hyperglycemia that is frequently caused [...]

Chronic inflammation plays a pivotal role in insulin resistance and type 2 diabetes, yet the mechanisms are not completely understood. Here, we demonstrated that serum LPS levels were significantly higher in newly diagnosed diabetic patients than in normal control. miR-145 level in peripheral blood mononuclear cells decreased in type 2 diabetics. LPS repressed the transcription of miR-143/145 cluster and decreased miR-145 levels. Attenuation of miR-145 activity by anti-miR-145 triggered liver inflammation and increased serum chemokines in C57BL/6 J mice. Conversely, lentivirus-mediated miR-145 overexpression inhibited macrophage infiltration, reduced body weight, and improved glucose metabolism in db/db mice. And miR-145 overexpression markedly reduced plaque size in the aorta in ApoE−/− mice. Both OPG and KLF5 were targets of miR-145. miR-145 repressed cell proliferation and induced apoptosis partially by targeting OPG and KLF5. miR-145 also suppressed NF-κB activation by targeting OPG and KLF5. Our findings provide an association of the environment with the progress of metabolic disorders. Increasing miR-145 may be a new potential therapeutic strategy in preventing and treating metabolic diseases such as type 2 diabetes and atherosclerosis. [ABSTRACT FROM AUTHOR]

Objective: To investigate the relationship between diabetic retinopathy, neuropathy and low ankle-brachial index in mild-to-moderate chronic kidney disease of type 2 diabetic patients. Methods: We enrolled 875 type 2 diabetic patients who were divided into two phenotypes (with or without albuminuria) and stratified into three groups (stage 1 with estimated glomerular filtration rate ⩾ 90 mL/min/1.73 m2, stage 2 with estimated glomerular filtration rate of 60–89, stage 3 with estimated glomerular filtration rate of 30–59). The prevalence of diabetic retinopathy, neuropathy and low ankle-brachial index was compared and the risk factors of renal impairment were determined. Results: Among chronic kidney disease stages, the prevalence of diabetic retinopathy increased from 42.5%, 56.6% to 66.7% in albuminuric subjects and from 29.4%, 33.0% to 50.0% with no significant trend in normoalbuminuric subjects (p = 0.005, 0.007 and 0.399 compared with albuminuric subjects in each stage). There was a significantly increased prevalence of low ankle-brachial index (17.5%, 22.6% and 44.4%) in normoalbuminuric subjects but no significant trend in albuminuric subjects. Diabetic retinopathy (odds ratio = 2.474, 95% confidence interval = 1.009–6.068) was an independent risk factor of declining kidney function in albuminuric patients. Conclusion: The prevalence of diabetic retinopathy was graded according to the estimated glomerular filtration rate declining in albuminuric patients while the prevalence of low ankle-brachial index was gradually increased in normoalbuminuric patients, indicating the diverse underlying mechanisms of mild to moderate chronic kidney disease between these two phenotypes. [ABSTRACT FROM AUTHOR]

Objective: To investigate the relationship between ankle-branchial index (ABI) and cardiovascular disease in type 2 diabetes patients.Methods: A total of 634 inpatients with type 2 diabetes were recruited in this cross-sectional study. All patients were measured with ABI and computed tomography angiography (CTA) scan for coronary artery disease (CAD). According to ABI values, patients were divided into three groups: low-ABI group (ABI < 0.9, n = 259), normal-ABI group (ABI = 0.9-1.3, n = 272), and high-ABI group (ABI > 1.3, n = 103). According to the manifestation of coronary CTA, the patients were divided into CAD group (n = 348) and non-CAD group (n = 286). Their clinical data and biochemical parameters were compared and analysed.Results: The prevalence of CAD in low-ABI group (90%) was significantly higher than that of normal-ABI group (33%) and high-ABI group (25%) (both P < 0.01). Spearman correlation analysis showed that age, sex, duration, spontaneous bacterial peritonitis, total cholesterol (TC), triglyceride, low-density lipoprotein cholesterol (LDL-C), serum creatinine, and glycosylated haemoglobin (HbA1c ) were positively correlated with CAD, and high-density lipoprotein cholesterol (HDL-C), glomerular filtration rate, and ABI were negatively correlated with CAD. Logistic regression analysis further revealed that age, sex, duration, TC, HDL-C, LDL-C, HbA1c , and ABI were independent risk factors of CAD. After all potential confounders is adjusted, the risk of CAD in low-ABI group still increased over four times than the normal-ABI group (odds ratio [OR], 5.32; 95% CI, 1.973-16.5; P < 0.001). In female patients, this risk increased more than nine times (OR, 10.63; 95% CI, 3.416-17.8; P < 0.001). Receiver-operating characteristic analysis indicated that ABI < 1.045 predicted the occurrence of CAD (sensitivity, 79.7%; specificity, 71.5%; P < 0.01).Conclusions: ABI is an independent risk factor for CAD and may be a potential simple screening instrument for CAD in Chinese type 2 diabetic patients, especially in elder women. [ABSTRACT FROM AUTHOR]

Objective: To investigate the clinical features of non-alcoholic fatty liver disease (NAFLD) and its relationship with serum C-peptide levels in patients with latent autoimmune diabetes in adults (LADA)., Methods: A total of 155 patients with LADA who had no drinking history and were hospitalized in department of endocrinology and metabolism from January 2007 to June 2009 were divided into two groups, including patients with LADA but without NAFLD and patients with both LADA and NAFLD, according to Chinese medical association's guidelines of NAFLD and hepatic ultrasound result. Their clinical data and results of laboratory examinations were collected and analyzed, including medications, blood pressure, weight, height, waist circumference, hip circumference, fasting plasma glucose, 2 h postprandial plasma glucose, fasting C-peptide, 2 h postprandial C-peptide, hemoglobin A1c, renal function, liver function, blood lipid and C-reactive protein. The clinical features between two groups were compared and the relationship between serum C-peptide and NAFLD were also analyzed., Results: Compared to the patients with LADA but without NAFLD, patients with both LADA and NAFLD had higher alanine aminotransferase (ALT), aspartate aminotransferase (AST) and gamma-glutamyl transferase (γ-GT) (all P<0.01), but the serum total bilirubin (TBI) and direct bilirubin (DBI) level had no significant inter-group difference (P>0.05). The patients with both LADA and NAFLD had higher fasting C-peptide [0.62(0.33-0.93) vs 0.17 (0.05-0.50) nmol/L, P<0.001], 2 h postprandial C-peptide [1.57(0.78-1.88) vs 0.42(0.06-1.01) nmol/L, P<0.001] and more severe insulin resistance [0.8(1.0-2.5) vs 0.6(0.2-1.3), P<0.001]. Logistic regression analysis showed that there was a significant association between fasting C-peptide and the presence of NAFLD after controlling other confounding factors in patients with LADA., Conclusions: The patients with both LADA and NAFLD had more severe metabolic disorders and insulin resistance. Serum fasting C peptide was independently associated with the presence of NAFLD in patients with LADA.

The family with sequence similarity 172, member A (FAM172A) is a hypothetical protein. We recently cloned the FAM172A gene from normal human aortic tissues. In a previous study we also showed that the FAM172A gene was up-regulated by high glucose levels in macrophages. In the present study, we further identified the FAM172A protein at the level of translation and studied the effects of high glucose levels on its expression in human aortic smooth muscle cells. The FAM172A gene was subcloned into the eukaryotic expression vectors, PDC315 and pEGFP-N2. The cloned sequence shows an open reading frame of 1251 nucleotides encoding a protein of 416 amino acids. We further expressed the recombinant FAM172A protein and generated rabbit anti-human FAM172A polyclonal antibodies. The FAM172A protein was identified for the first time at the translation level by Western blot analysis. Western blotting also demonstrated that the FAM172A protein could be detected in human aortic endothelial, human aortic smooth muscle cells and THP-1-derived macrophages, the highest expression being observed in the human aortic smooth muscle cells. By a combination of bioinformatics and confocal laser scanning microscopy, we found that the FAM172A protein in HEK293 cells, was mainly located in the nucleus, and that there was an Arb2 conserved domain in the FAM172A protein sequence. We also presented evidence that the FAM172 protein expression in human aortic smooth muscle cells was up-regulated by high glucose levels in a concentration-dependent and time-course manner. We speculated that as a novel protein, FAM172A could be involved in the pathogenesis of high glucose-induced vascular damage.