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Objective:To evaluate perirenal adipose tissue inflammation in obesity-related glomerulopathy induced by a high-fat diet in C57BL/6J mice and further explore its probable mechanism.Methods:Twelve 8-10-week-old male C57BL/6J mice were divided into normal diet group (ND, n=6) and high-fat diet group (HFD, n=6) using simple random sampling method. After 14 weeks, the blood and kidney tissue were sampled, and the pathological change in the kidney and perirenal adipose tissue was observed by hematoxylin-eosin, periodic acid-Schiff, and Masson staining. The mRNA expression of tumor necrosis factor-α (TNF-α), M1-type macrophage marker CD11c, interleukin (IL)-1β, monocyte chemotactic protein-1 (MCP-1), IL-10, transforming growth factor-β1, M2-type macrophage marker CD206 and fibronectin 1 in perirenal fat was detected by real-time fluorescence quantitative PCR. The expression of macrophages marker F4/80, CD68 and leukocyte common antigen (LCA) in the kidney and perirenal adipose tissue was detected by immunohistochemistry. Results:After 14 weeks of feeding, compared with mice in the ND group, the weight of mice in the HFD group was significantly higher [(35.83±1.19) g vs (24.06±0.37) g, P<0.05]. In the HFD group, perirenal adipocyte hyperplasia, accompanied by glomerular hyperplasia, mesangial matrix hyperplasia and renal interstitial fibrosis, and other pathological changes was observed (all P<0.05). The level of blood glucose, blood lipid, serum creatinine and blood urea nitrogen was also significantly higher (all P<0.05). The mRNA expression of TNF-α, CD11c, IL-1β and MCP-1 related to M1 macrophages in the perirenal adipose tissue was higher (all P<0.05), and immunohistochemistry showed that the expression of F4/80, CD68 and LCA in the perirenal adipose tissue was higher in HFD group (all P<0.05). The above results showed that the number of macrophages and inflammatory cells in the perirenal adipose tissue was significantly greater in the HFD group than those in the ND group. Pearson linear correlation analysis showed that the average perirenal fat area was positively correlated with macrophages number in perirenal adipose tissue, several morphological indexes such as glomerular cross-sectional area and renal function injury indexes such as blood urea nitrogen (all P<0.05). Conclusion:The C57BL/6J mice model of obesity-related glomerulopathy induced by a high-fat diet is successfully established, and the perirenal adipose tissue shows an obvious inflammatory response, with the macrophages significantly polarized mainly in the pro-inflammatory direction towards the M1-type macrophages.
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objective To investigate the effect of toll-like receptor 4 (TLR4) in RAW264.7 macrophage inflammation induced by palmitic acid and its possible mechanisms thereof. Methods C57BL/6J male mice were fed normal (control group) or high-fat diet (high-fat group) for 18 weeks. The serum level of free fatty acids (FFA) and mRNA levels of inflammatory cytokines in visceral adipose (TNF-α, IL-6 and MCP-1) were detected. Then, palmitic acid (150μmol/L and 300 μmol/L) was applied to stimulate RAW264.7 macrophage, the mRNA expression and the secretion level of cytokines were detected. Meanwhile, TLR4 protein level, the nuclear translocation and intracellular level of NF-κB p65 were also detected. After TLR4 inhibition by siRNA transfection, the mRNA expression and the secretion level of cytokines were detected. Results The body weight and Lee's index were significantly higher in high-fat group than those of control group (P<0.05). The serum level of FFA and mRNA levels of inflammatory cytokines (TNF-α, IL-6 and MCP-1) in visceral adipose were significantly higher in high-fat group than those of control group (P<0.05). Compared with mice without FFA (BSA group), the mRNA expression and the levels of TNF-α, IL-6, and MCP-1 were significantly increased (P<0.05), and the protein expression of TLR4 and NF-κB phosphorylated protein were up-regulated (P<0.05) in mice treated with palmitic acid (150μmol/L and 300μmol/L). The nuclear translocation and intracellular level of NF-κB p65 were increased in mice treated with palmitic acid 300μmol/L than mice in BSA group (P<0.05). The mRNA levels of TNF-α, IL-6 and MCP-1 and their secretion level were significantly decreased after TLR4 siRNA transfection (P<0.05). Conclusion These results suggest that TLR4 may mediate the inflammation in RAW264.7 macrophage stimulated by palmitic acid by inducing inflammatory cytokines (TNF-α, IL-6 and MCP-1), and which may be related with the activation of NF-κB.
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As fibras alimentares vêm despertando interesse de especialistas das áreas de nutrição e saúde. Elas contribuem para a redução do risco de desenvolvimento de doenças cardiovasculares, além de ajudar no processo de perda de peso, principalmente quando seu consumo é associado à atividade física. Entretanto existem poucos trabalhos associando o uso de fibras solúveis à uma dieta hipercalórica e ao exercício físico. Assim, objetivo desse estudo foi investigar os efeitos das fibras solúveis sobre a aorta torácica e perfil lipídico de ratos machos wistar sedentários e treinados submetidos à dieta de cafeteria. Os parâmetros morfométrico e estereológico: espessura íntima-média e densidade de volume do músculo liso e do colágeno e o perfil lipídico foram determinados. Não foram observadas alterações na espessura da parede vascular, densidade de volume do músculo liso e colágeno. No entanto, o perfil lipídico apresentou-se alterado com o uso da dieta de cafeteria. A fibra alimentar associada ao treinamento aeróbio e a uma dieta balanceada apresentou resultado eficaz, não alterando a morfologia do vaso.
Food fibers have recently been in the limelight of nutrition and health experts. They reduce the development of cardiovascular diseases and help in the process of loss weight especially when their intake is associated with physical activity. However, few studies are extant on the use of soluble fibers associated to a hypercalorie diet and physical exercise. Current analysis deals with the effects of soluble fibers on the thoracic aorta and lipid profile of sedentary and trained male Wistar rats subjected to a cafeteria diet. Morphometric and stereological parameters comprised mid thickness and density of the volume of the smooth muscle and collagen, and lipid profile. No changes were reported on the thickness of the vascular wall, density of volume of the smooth muscle and collagen. However, lipid profile was modified due to the cafeteria diet. Food fiber associated with aerobic training and with a balanced diet provided an efficacious result with no alteration in the vase´s morphology.
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Rats , Aorta , Dietary Fiber , Diet , Obesity , Exercise , Diet, Food, and NutritionABSTRACT
Objective To analyze the protein expression changes of retina in diabetic mice using isobaric tags for relative and absolute quantitation (iTRAQ) approach and to study proteins of apoptosis.Methods 8 diabetic mice were chosen as the diabetic model group (DM group),8diabetic mice as the normal control group.The animals were housed in wire-bottomed cages and received normal pellet chow and tap water in a constant environment.After 10 weeks,all mice were killed,and their retina were dissected.After hematoxylin and eosin(H&E) staining,the sections of retina were examined using light microscopy.The changes of protein expression in retina were studied using iTRAQ approach.Expression of apoptosis associated proteins was analyzed using ingenuity pathway analysis (IPA).Results Compared with control group,mice retina in DM group developed looser structures,tissue edema and obvious telangiectasia under light microscopy.Using iTRAQ approach,a total of 348 differential proteins were identified.Among those proteins,16 proteins were related with apoptosis,including Ataxin-10,Protein NDRG1,mucin-4,Aquaporin-1 and annexin A4,etc.There were 8 apoptosis-related proteins in retina with up-regulation,and the other 8 proteins with down-regulation in the DM group.The relationship between these proteins were analyzed and charted by IPA.Conclusions Apoptosis may be involved in the development of diabetic retinopathy.The identification of the apoptosis-related proteins will be helpful for the further study.