Clinical trials and animal experimental studies have demonstrated an association of arterial baroreflex impairment with the prognosis and mortality of cardiovascular diseases and diabetes. As a primary part of the arterial baroreflex arc, the pressure sensitivity of arterial baroreceptors is blunted and involved in arterial baroreflex dysfunction in cardiovascular diseases and diabetes. Changes in the arterial vascular walls, mechanosensitive ion channels, and voltage-gated ion channels contribute to the attenuation of arterial baroreceptor sensitivity. Some endogenous substances (such as angiotensin II and superoxide anion) can modulate these morphological and functional alterations through intracellular signaling pathways in impaired arterial baroreceptors. Arterial baroreceptors can be considered as a potential therapeutic target to improve the prognosis of patients with cardiovascular diseases and diabetes.
Animals ; Baroreflex ; physiology ; Blood Pressure ; physiology ; Cardiovascular Diseases ; metabolism ; physiopathology ; Diabetes Mellitus ; metabolism ; physiopathology ; Humans ; Ion Channels ; metabolism ; Pressoreceptors ; metabolism

Nonalcoholic fatty liver disease (NAFLD) and type 2 Diabetes Mellitus (T2DM) are highly prevalent diseases and are closely associated, with NAFLD being present in the majority of T2DM patients. In Asian traditional medicine, Mori Cortex is widely used for the treatment of diabetes and hyperlipidemia. However, whether it has a therapeutic effect on T2DM associated with NAFLD is still unknown. The present study showed that the oral treatment with Mori Cortex extract (MCE; 10 g·kg·d) lowered the blood lipid levels and reversed insulin resistance (IR) in high fat-diet/streptozotocin-induced type 2 diabetes in rats. The expression levels of sterol receptor element-binding protein-1c (SREBP-1c) and carbohydrate-responsive element binding protein (ChREBP), which are involved in steatosis in NAFLD rats, were measured in the liver samples. MCE decreased the protein and mRNA expression levels of SREBP-1c and ChREBP. In conclusion, down-regulation of SREBP-1c and ChREBP might contribute to the protective effect of MCE on hepatic injury and IR in the rats with T2DM associated with NAFLD.
Alanine Transaminase ; blood ; Animals ; Aspartate Aminotransferases ; blood ; Basic Helix-Loop-Helix Leucine Zipper Transcription Factors ; genetics ; Diabetes Mellitus, Type 2 ; blood ; chemically induced ; drug therapy ; metabolism ; Diet, High-Fat ; adverse effects ; Disease Models, Animal ; Down-Regulation ; drug effects ; Insulin ; blood ; Insulin Resistance ; physiology ; Lipid Metabolism ; drug effects ; genetics ; Liver ; drug effects ; physiopathology ; Male ; Morus ; Non-alcoholic Fatty Liver Disease ; blood ; chemically induced ; drug therapy ; metabolism ; Phytotherapy ; Plant Extracts ; pharmacology ; therapeutic use ; Rats ; Rats, Sprague-Dawley ; Streptozocin

OBJECTIVE: The present study aims at determining the stability of a popular type 2 diabetes rat model induced by a high-fat diet combined with a low-dose streptozotocin injection. METHODS: Wistar rats were fed with a high-fat diet for 8 weeks followed by a one-time injection of 25 or 35 mg/kg streptozotocin to induce type 2 diabetes. Then the diabetic rats were fed with regular diet/high-fat diet for 4 weeks. Changes in biochemical parameters were monitored during the 4 weeks. RESULTS: All the rats developed more severe dyslipidemia and hepatic dysfunction after streptozotocin injection. The features of 35 mg/kg streptozotocin rats more resembled type 1 diabetes with decreased body weight and blood insulin. Rats with 25 mg/kg streptozotocin followed by normal diet feeding showed normalized blood glucose level and pancreatic structure, indicating that normal diet might help recovery from certain symptoms of type 2 diabetes. In comparison, diabetic rats fed with high-fat diet presented decreased but relatively stable blood glucose level, and this was significantly higher than that of the control group (P<0.05). CONCLUSIONS This model easily recovers with normal diet feeding. A high-fat diet is suggested as the background diet in future pharmacological studies using this model.
Animals ; Blood Glucose ; metabolism ; Diabetes Mellitus, Experimental ; blood ; etiology ; physiopathology ; Diabetes Mellitus, Type 2 ; blood ; etiology ; physiopathology ; Diet, High-Fat ; adverse effects ; Insulin ; blood ; Lipids ; blood ; Liver ; drug effects ; pathology ; physiopathology ; Male ; Malondialdehyde ; blood ; Oxidative Stress ; Rats ; Rats, Wistar ; Streptozocin ; administration & dosage ; toxicity ; Superoxide Dismutase ; blood ; Uric Acid ; blood

OBJECTIVES: To study the effects of ursolic acid on liver injury in diabetic mice induced by high-fat diet combined with streptozotocin(STZ), and to explore its possible mechanisms. METHODS: Diabetes mellitus was induced in twenty male ICR mice by a combination of high-fat diet for 6 weeks with low-dose streptozotocin (30 mg/kg, i. p.) for 5 consecutive days. After 9 days, fasting blood glucose levels were determined. Mice with fasting blood glucose levels exceeded 11. 1 mmol/L were diagnosed as diabetic mice and selected for further experiment. These mice were randomly divided into two groups(each group of 10):diabetic group, ursolic acid group (100 mg/kg, i. g.), and another 10 mice were set as control group. After continuous administration for 8 weeks, body weight (BW) were weighed, fasting blood glucose (FBG), total cholesterol (TC), triglyceride (TG), alanine aminotransferase (ALT), aspartate transaminase (AST) in serum and superoxide dismutase (SOD), malondialdehyde (MDA) in liver were measured. HE staining was used to observe pathological changes of liver tissue. RESULTS: Compared with the control group, the level of FBG, TC, TG, ALT, AST, MDA were dramatically increased (<0. 05, <0. 01) and SOD was markedly decreased (<0.01) in the diabetic group; HE staining showed that parts of liver cells swelled and had a light fatty degeneration as well as lymphocyte infiltrated around the portal area in model group. Compared with the diabetic group, the level of FBG, TC, TG, ALT, AST, MDA were significantly declined (<0.05, <0.01) and SOD was considerably increased (<0.01) in the ursolic acid group; HE staining showed that the liver cells relatively arranged in order, edema was not obvious and inflammatory cells infiltrated lightly in the ursolic acid group. CONCLUSIONS Ursolic acid has a protective effect on liver injury in diabetic mice induced by high-fat diet combined with STZ by intraperitoneal ingector, and its mechanism may be associated with lowering blood glucose, regulating the lipid metabolism, reducing oxidative stress and enhancing the ability of anti-oxidation in liver.
Alanine Transaminase ; blood ; Animals ; Aspartate Aminotransferases ; blood ; Blood Glucose ; Cholesterol ; blood ; Diabetes Mellitus, Experimental ; physiopathology ; Diet, High-Fat ; Fatty Liver ; drug therapy ; Liver ; metabolism ; physiopathology ; Male ; Malondialdehyde ; metabolism ; Mice ; Mice, Inbred ICR ; Random Allocation ; Superoxide Dismutase ; metabolism ; Triglycerides ; blood ; Triterpenes ; pharmacology

Diabetes is a widespread, rapidly increasing metabolic disease that is driven by hyperglycemia. Early glycemic control is of primary importance to avoid vascular complications including development of retinal disorders leading to blindness, end-stage renal disease, and accelerated atherosclerosis with a higher risk of myocardial infarction, stroke and limb amputations. Even after hyperglycemia has been brought under control, "metabolic memory," a cluster of irreversible metabolic changes that allow diabetes to progress, may persist depending on the duration of hyperglycemia. Manipulation of bile acid (BA) receptors and the BA pool have been shown to be useful in establishing glycemic control in diabetes due to their ability to regulate energy metabolism by binding and activating nuclear transcription factors such as farnesoid X receptor (FXR) in liver and intestine as well as the G-protein coupled receptor, TGR5, in enteroendocrine cells and pancreatic β-cells. The downstream targets of BA activated FXR, FGF15/21, are also important for glucose/insulin homeostasis. In this review we will discuss the effect of BAs on glucose and lipid metabolism and explore recent research on establishing glycemic control in diabetes through the manipulation of BAs and their receptors in the liver, intestine and pancreas, alteration of the enterohepatic circulation, bariatric surgery and alignment of circadian rhythms.
Animals ; Bile Acids and Salts ; blood ; metabolism ; Blood Glucose ; drug effects ; metabolism ; Circadian Rhythm ; Diabetes Mellitus ; blood ; drug therapy ; metabolism ; Energy Metabolism ; Homeostasis ; Humans ; Hyperglycemia ; metabolism ; physiopathology ; Hypoglycemic Agents ; therapeutic use ; Intestinal Mucosa ; metabolism ; Intestines ; drug effects ; Lipid Metabolism ; Liver ; drug effects ; metabolism ; Receptors, Cytoplasmic and Nuclear ; metabolism ; Receptors, G-Protein-Coupled ; metabolism ; Signal Transduction

PURPOSE: Diabetes mellitus (DM) is the most common cause of end-stage renal disease (ESRD) and an important risk factor for cardiovascular (CV) disease. We investigated the impact of DM on subclinical CV damage by comprehensive screening protocol in ESRD patients. MATERIALS AND METHODS: Echocardiography, coronary computed tomography angiogram, 24-h ambulatory blood pressure monitoring, and central blood pressure with pulse wave velocity (PWV) were performed in 91 ESRD patients from the Cardiovascular and Metabolic disease Etiology Research Center-HIgh risk cohort. RESULTS: The DM group (n=38) had higher systolic blood pressure than the non-DM group (n=53), however, other clinical CV risk factors were not different between two groups. Central aortic systolic pressure (148.7±29.8 mm Hg vs. 133.7±27.0 mm Hg, p= 0.014), PWV (12.1±2.7 m/s vs. 9.4±2.1 m/s, p<0.001), and early mitral inflow to early mitral annulus velocity (16.7±6.4 vs. 13.7±5.9, p=0.026) were higher in the DM group. Although the prevalence of coronary artery disease (CAD) was not different between the DM and the non-DM group (95% vs. 84.4%, p=0.471), the severity of CAD was higher in the DM group (p=0.01). In multivariate regression analysis, DM was an independent determinant for central systolic pressure (p=0.011), PWV (p<0.001) and the prevalence of CAD (p=0.046). CONCLUSION: Diabetic ESRD patients have higher central systolic pressure and more advanced arteriosclerosis than the non-DM control group. These findings suggest that screening for subclinical CV damage may be helpful for diabetic ESRD patients.
Aged ; Aorta ; Biomarkers ; Blood Pressure/physiology ; Blood Pressure Monitoring, Ambulatory ; Coronary Artery Disease/diagnostic imaging/*physiopathology ; Diabetes Mellitus/*physiopathology ; Diabetic Nephropathies/physiopathology ; Echocardiography ; Female ; Humans ; Kidney Failure, Chronic/*physiopathology ; Male ; Middle Aged ; Pulse Wave Analysis ; Regression Analysis ; Risk Factors ; Systole/physiology

Aged ; Blood Glucose ; metabolism ; Diabetes Mellitus, Type 2 ; blood ; physiopathology ; Female ; Glycated Hemoglobin A ; metabolism ; Humans ; Male ; Middle Aged ; Neuropsychological Tests

OBJECTIVETo explore the mechanism of the protective effects of Panax notoginseng saponins (PNS) on kidney in diabetic rats.

METHODSDiabetic rat model was obtained by intravenous injection of alloxan, and the rats were divided into model, PNS-100 mg/(kg day) and PNS-200 mg/(kg day) groups, 10 each. Another 10 rats injected with saline were served as control. Periodic acid-Schiff staining and immunological histological chemistry were used to observe histomorphology and tissue expression of bone morphogenetic protein-7 (BMP-7). Silent information regulator 1 (SIRT1) was silenced in rat mesangial cells by RNA interference. The mRNA expressions of SIRT-1, monocyte chemoattractant protein-1 (MCP-1), transforming growth factor β1 (TGF-β1) and plasminogen activator inhibitor-1 (PAI-1) were analyzed by reverse transcription polymerase chain reaction. The protein expressions of SIRT1 and the acetylation of nuclear factor κB (NF-κB) P65 were determined by western blotting. The concentration of MCP-1, TGF-β1 and malondialdehyde (MDA) in culture supernatant were detected by enzyme-linked immuno sorbent assay. The activity of superoxide dismutase (SOD) was detected by the classical method of nitrogen and blue four.

RESULTSIn diabetic model rats, PNS could not only reduce blood glucose and lipid (P<0.01), but also increase protein level of BMP-7 and inhibit PAI-1 expression for suppressing fibrosis of the kidney. In rat mesangial cells, PNS could up-regulate the expression of SIRT1 (P<0.01) and in turn suppress the transcription of TGF-β1 (P<0.05) and MCP-1 (P<0.05). PNS could also reverse the increased acetylation of NF-κB p65 by high glucose. In addition, redox regulation factor MDA was down-regulated (P<0.05) and SOD was up-regulated (P<0.01), which were both induced by SIRT1 up-regulation.

CONCLUSIONSPNS could protect kidney from diabetes with the possible mechanism of up-regulating SIRT1, therefore inhibiting inflammation through decreasing the induction of inflammatory cytokines and TGF-β1, as well as activating antioxidant proteins.

Acetylation ; drug effects ; Animals ; Antioxidants ; metabolism ; Blood Glucose ; metabolism ; Bone Morphogenetic Protein 7 ; metabolism ; Chemokine CCL2 ; metabolism ; Diabetes Mellitus, Experimental ; blood ; drug therapy ; genetics ; physiopathology ; Gene Knockdown Techniques ; Immunohistochemistry ; Kidney ; drug effects ; pathology ; Kidney Function Tests ; Lipids ; blood ; Male ; Malondialdehyde ; metabolism ; Mesangial Cells ; drug effects ; metabolism ; Oxidative Stress ; drug effects ; Panax notoginseng ; chemistry ; Plasminogen Activator Inhibitor 1 ; genetics ; metabolism ; Protective Agents ; pharmacology ; therapeutic use ; Rats, Sprague-Dawley ; Saponins ; pharmacology ; therapeutic use ; Sirtuin 1 ; genetics ; Superoxide Dismutase ; metabolism ; Transcription Factor RelA ; metabolism ; Transcription, Genetic ; drug effects ; Transforming Growth Factor beta1 ; metabolism ; Up-Regulation ; drug effects

OBJECTIVETo investigate the roles of microRNA-21 (miR-21) in the pathogenesis of non-alcoholic fatty liver disease (NAFLD) with high-fat diet-induced insulin resistance (IR) and diabetes mellitus (DM) mice model.

METHODSEight-week-old C57BL/6 mice were allocated into control group, IR group, and DM group. Body mass was recorded. Intraperitoneal glucose tolerance test was performed to determine any abnormal glucose metabolism. The liver pathological changes were detected by biopsy. Changes in free blood glucose, free serum insulin, blood fat and tumor necrosis factor Α level were measured. Differences in miR-21 expression and peroxidase proliferator-activated receptor subtypes (PPAR-Γ and PPAR-Α) and adipocyte fatty acid binding protein (aP2) in the liver were detected both at the mRNA and protein levels.

RESULTSAfter one 8-week high-fat diet, the body mass, free serum insulin, and homeostasis model IR index significantly increased in the IR group (P<0.01, P<0.05, compared with control group), while the free blood glucose increased and the free serum insulin decreased in DM group (P<0.05). Free serum insulin level were significantly increased in IR group (P<0.05). Serum tumor necrosis factor-Α levels exhibited an upward trend in control group, IR group, and DM group (P<0.05, P<0.01). With exacerbation in NAFLD, liver miR-21 expression level went further down in both IR and DM groups (P<0.05). The downregulated miR-21 expression level showed negative correlation with upregulated PPAR-Α, ΑP2, and PPAR-Γ genetic expression (r=-0.696, r=-0.664, and r=-0.766, respectively; P<0.05) in IR group and with upregulated PPAR-Α and PPAR-Γ genetic expression in DM group (r=-0.676 and r=-0.550, respectively; P<0.05). In terms of the changes in protein expression level,only on the protein expressions of aP2 and PPAR-Γ in IR group showed significant change (P<0.05, P<0.01, compared with control group).

CONCLUSIONSThe miR-21 expression is downregulated in both IR and DM-induced NAFLD mice. It may be involved in the pathogenesis of NAFLD by regulating the expressions of PPAR subtypes.

Animals ; Blood Glucose ; analysis ; Diabetes Mellitus, Experimental ; physiopathology ; Diet, High-Fat ; Disease Models, Animal ; Insulin ; blood ; Insulin Resistance ; Mice ; Mice, Inbred C57BL ; MicroRNAs ; metabolism ; Non-alcoholic Fatty Liver Disease ; physiopathology ; PPAR alpha ; metabolism ; PPAR gamma ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism

Objective To establish a Daphnia model of alloxan-induced diabetes. Methods Daphnia were exposed to three different concentrations of alloxan (3, 5, and 10 mmol/L) for 30 minutes. Blood glucose and survival rate were recorded for 72 hours after alloxan insult. Sequence analysis and phylogenetic inference for glucose transporters (GLUT) were clustered with the maximum-likelihood method. Using reverse transcription and quantitative polymerase chain reaction techniques, we investigated the transcriptional changes of GLUT at 12 hours after alloxan (5 mmol/L) exposure. Results Compared with control, 3 mmol/L, and 5 mmol/L as well as 10 mmol/L alloxan initially induced transient blood glucose decline by 15% for 2 hours and 12 hours respectively. In Daphnia with 5 and 10 mmol/L alloxan, their blood glucose was persistently raised by about 150% since after 24-hour insult. Survival rate of Daphnia exposure to alloxan with concentrations of 3, 5, and 10 mmol/L were 90%, 75%, and 25% respectively. We predicted seven GLUT genes in the Daphnia genome and successfully amplified them using real-time polymerase chain reaction. Two of seven GLUT transcripts were down-regulated in Daphnia with 5 mmol/L alloxan-induced diabetes. Conclusion Alloxan-induced diabetes model was successfully established in the Daphnia pulex, suggesting diabetes-relevant experiments can be conducted using Daphnia.
Alloxan ; Animals ; Blood Glucose ; analysis ; Daphnia ; Diabetes Mellitus, Experimental ; chemically induced ; physiopathology ; Disease Models, Animal ; Gene Expression Regulation ; Glucose Transport Proteins, Facilitative ; genetics ; metabolism ; Likelihood Functions ; Phylogeny ; Real-Time Polymerase Chain Reaction