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Roux-en-Y bariatric surgery has been shown to have a remarkable and sustainable improvement in type 2 diabetes. Recent clinical studies have shown that bariatric surgery can improve or halt the development of diabetic microvascular complications such as nephropathy. However, the exact underlying mechanisms of surgical procedures are unknown. Here, we have investigated the effects of Roux-en-Y esophagojejunostomy (RYEJ) on renal function and inflammation and fibrosis biomarkers for renal injury in type 2 diabetic rats. Sprague–Dawley rats with high fat diet and streptozotocin (STZ)-induced diabetes were randomly assigned into four groups: diabetic nephropathy (DN), DN treated with food restriction (DN-FR), DN treated with RYEJ surgery (DN-RYEJ), and DN-RYEJ sham (n = 6/group). Age-matched normal rats were assigned as control group. RYEJ and sham surgeries were performed. Hyperinsulinemic–euglycemic clamps with tracer infusion were completed to assess insulin sensitivity. Twenty-four hour urine albumin excretion rate (UAER) and glomerular filtration rate (GFR) were measured. The renal pathological injury was assessed by hematoxylin and eosin (HE) staining. Kidney messenger RNA (mRNA) and/or protein content/distribution of phospho-c-Jun NH2-terminal kinase (JNK), monocyte chemoattractant protein (MCP)-1, transforming growth factor (TGF)-β1, and mitogen-activated protein kinase phosphatase 5 (MKP5) were evaluated by real-time PCR and/or Western blotting/immunohistochemistry. Roux-en-Y esophagojejunostomy improved insulin sensitivity. RYEJ ameliorated renal function by improving UAER and GFR and attenuated glomerular hypertrophy after surgery. RYEJ also significantly downregulated the levels of JNK-mediated inflammatory response and upregulated the level of the anti-inflammatory mediator MKP5. Roux-en-Y esophagojejunostomy alleviates insulin resistance. RYEJ surgery ameliorated renal function and attenuated glomerular hypertrophy in a DN rat model. The considerable nephroprotective function may be mainly attributed to the reduced inflammatory and fibrotic biomarkers after RYEJ. The improvements in renal function and inflammation are not wholly dependent on the magnitude of weight loss.

The target of this research is to obtain valuable inspiration for tissue engineering in nerve regeneration. The effect of topographic feature of plate material surface on the crawl behavior of earthworm was studied. A total of 278 earthworms, with weight 1.2–5.1 g and diameter 2.5–7.0 mm, were divided into three groups (A, B, C) according to their weight. Earthworms always crawl straightly to a certain direction on ground or plate material. When earthworm crawled on the ground surface with regular grooves (straight line or curve with different curvature, depth and width of 3.0–6.0 mm), it was found that (1) earthworm crawled faster on surface with less grooves curvature, fastest on surface with straight grooves and that (2) the earthworm got into grooves easier with less the acute angle between the crawl direction and the grooves. When the earthworm crawled on the plate with different roughness, it was also found that the earthworm crawled much slower on smooth surface, such as glass, than on rough surface, such as cement plate, without calendering. We thought that, in point of the effect of the surface topographic feature of contacting materials, there may be some analogy between crawl behavior of the earthworm and the nerve growth of mammal.

In order to establish a novel artificial muscle model, an ionized fibrous hydrogel assembly (FHM) was prepared by means of surface-grafting acrylonitrile onto cellulose fiber and consequent hydrolysis. The structure and character of FHM was investigated. The FHM shows excellent chemomechanical character. This feature is closely interrelated to its molecular, morphological structure and texture.

Background Roux-en-Y gastric bypass (RYGB) surgery for the treatment of obesity leads to long-term diabetes remission in approximately 80% of cases. The aim of this study was to investigate the effects of RYGB on hepatic and peripheral insulin sensitivity in type 2 diabetic rats and their possible mechanisms. We also tested the hypothesis that RYGB reduces lipid content and improves insulin sensitivity in hepatocytes and skeletal muscle cells. Methods Sprague–Dawley rats were divided into 4 groups: diabetic RYGB group (n = 18), diabetic RYGB sham group (n = 6), diabetic group (n = 6), and nondiabetic control group (n = 6). The hyperinsulinemic-euglycemic clamp with tracer infusion was completed at 2, 4, and 8 weeks postoperatively to assess insulin sensitivity. The lipid content in liver and muscle tissue was examined. Results Postoperatively, the diabetic RYGB group had significant decreases in weight, fat mass, and food intake. Two weeks after surgery, RYGB had significantly improved the hepatic insulin sensitivity index and decreased the hepatic triglyceride, total cholesterol, and fatty acyl-CoA content. The significantly increased insulin sensitivity and decreased lipid content in muscle were not detected until 4 weeks after RYGB surgery. The basal insulin and C-peptide concentrations were significantly lower than those in diabetic group by 2 weeks after RYGB. Conclusion The increased insulin sensitivity after RYGB occurs earlier in the liver than in the muscle and both may contribute to long-term remission of type 2 diabetes. Reduced lipid content of hepatocytes and skeletal muscle cells after RYGB may contribute to the improved insulin sensitivity in these cells.

Previous studies showed that early after Roux-en-Y gastric bypass (RYGB), there is a remarkable improvement in type 2 diabetes, which is characterized by insulin resistance. This study aims to gain insight into the underlying mechanisms of this effect. We determined the acute effects of RYGB on hepatic and peripheral insulin sensitivity. A rat model of type 2 diabetes was established using high-fat diet combined with streptozotocin (30 mg/kg, ip). Animals were divided into four groups: diabetic, diabetic RYGB, diabetic RYGB sham, and control rats. Hyperinsulinemic-euglycemic clamps with tracer infusion were completed at 2 weeks postoperatively to assess insulin sensitivity. Triglyceride concentration in liver and muscle tissues was determined. Protein kinase C (PKC) membrane translocation, protein expression of phospho-c-Jun NH2-terminal kinase (JNK), and phospho-IκB kinase β (IKKβ) were assessed with western blot. Malondialdehyde (MDA) and superoxide dismutase (SOD) activities in the liver were also measured. RYGB surgery significantly improved hepatic insulin sensitivity index and decreased hepatic triglyceride concentration (P

Aims We aimed to investigate the effects of LXRα, ChREBP and Elovl6 in the development of insulin resistance-induced by medium- and long-chain fatty acids. Methods Sprague Dawley rats were fed a standard chow diet (Control group) or a high-fat, high sucrose diet with different fat sources (coconut oil, lard, sunflower and fish oil) for 8 weeks. These oils were rich in medium-chain saturated fatty acids (MCFA group), long-chain saturated fatty acids (LCFA group), n-6 and n-3 long-chain polyunsaturated fatty acids (n-6 PUFA and n-3 PUFA groups), respectively, which had different chain lengths and degrees of unsaturation. Hyperinsulinemic–euglycemic clamp with [6- 3 H] glucose infusion was performed in conscious rats to assess hepatic insulin sensitivity. Results LCFA and n-6 PUFA groups induced hepatic insulin resistance and increased liver X receptor α (LXRα), carbohydrate response element binding protein (ChREBP) and long-chain fatty acid elongase 6 (Elovl6) expression in liver and white adipose tissue (WAT). Furthermore, LCFA and n-6 PUFA groups suppressed Akt serine 473 phosphorylation in liver and WAT. By contrast, in liver and WAT, MCFA and n-3 PUFA groups decreased LXRα, ChREBP and Elovl6 expression and improved insulin signaling and insulin resistance, but Akt serine 473 phosphorylation was not restored by MCFA group in WAT. Conclusions This study demonstrated that the mechanism of the different effects of medium- and long-chain fatty acids on hepatic insulin resistance involves LXRα, ChREBP and Elovl6 alternations in liver and WAT. It points to a new strategy for ameliorating insulin resistance and diabetes through intervention on Elovl6 or its control genes.