Impaired cholesterol metabolism affecting subventricular zone neurogenesis in ob/ob mice / 解剖学报

Objective To investigate the effect of cholesterol on the proliferation and differentiation of neural stem cells (NSCs) in ob/ob obese mice, and to explore the possible mechanism of central nervous systym dysfunction caused by obesity. Methods Selected 64-month-old ob/ob and wild type (WT) mice, and cell proliferation antigen (Ki67) and doublecortin (DCX) immunofluorescenct staining were used to detect ob/ob mice lateral ventricle subventricular zone (SVZ) neurogenesis level. Cultured SVZ NSCs isolated from 184-month-old ob/ob and WT mice, and BrdU incorporation experiment and β-III-tubulin (Tuj1) immunofluorescent staining were employed to detect the self-renewal and differentiation ability of NSCs. Matrix-assisted laser desorption/ionization time of flight mass spectrometry(MALDI- MS)was used to detect the lipid distribution in 4-month-old ob/ob and WT mice brain tissues, and measure the changes of cholesterol(ST) content and the expression genes related to cholesterol synthesis. Cultured 15 WT postnatal day 0(P0) mouse SVZ NSCs in vitro and electrotransfected with the small interfering RNA(siRNA) sequence of cholesterol synthesis rate-limiting enzyme 3-hydroxy-3-methyl-glutaryl coenzyme A reductase (Hmgcr) verified the knockdown efficiency, to detecte the effect of Hmgcr gene knockdown on NSCs by BrdU incorporation experiment and Tuj1 immunofluorescent staining. Results Compared with the WT mice, the number of Ki67

Anti-obesity effect of 11β-HSD1 inhibitor equisetin on ob/ob mice / 药学学报

Equisetin (EQST) belongs to polyketide (PKS)-nonribosomal peptide synthetase (NRPS) type compound with an inhibitory effect of 11β-hydroxysteroid dehydrogenase 1 (11β-HSD1) enzyme activity. This study investigated anti-obesity effect and insulin resistance improvement effect of EQST on high-fat diet (HFD)-induced ob/ob mice model. EQST treatment effectively reduced the body weight gain, fat weight gain and blood lipid content of model mice. All animal experiments were approved by the Medical Ethics Committee of Capital Institute of Pediatrics. EQST alleviated adipose tissue expansion and hepatic ballooning degeneration of model mice, and also effectively controlled the blood glucose content after glucose load and insulin load, showed a significant improvement in obesity and insulin resistance. EQST inhibited adipogenic proteins fatty acid-binding protein 4 (FABP4) and peroxisome proliferators-activated receptor γ (PPARγ), and upregulated thermogenic protein (uncoupling protein 1, UCP1) through suppressing 11β-HSD1 protein expression. In addition, EQST widely upregulates mitochondrial respiratory metabolism related proteins in adipose tissue and may improve insulin resistance through phosphatidylinositol-3-kinase (PI3K) pathway. Therefore, EQST plays an anti-obesity role by promoting adipose tissue thermogenesis and improving insulin resistance, which may provide reliable clues for improving obesity and diabetes.

Effect of Maiqi-Jiangtang pill on the glycolipid level in type 2 diabetic ob/ob mice / 国际中医中药杂志

Objective To investigate the effects of Maiqi-Jiangtang pill on the glycolipid level in type 2 diabetic ob/ob mice.Methods The 8-week old male ob/ob mice were randomly divided into Maiqi-Jiangtang pill high- (8 g/kg), medium- (4 g/kg), low- (2 g/kg) dose groups. All the mice orally adiministered with the drugs once a day for 10 weeks. The same week age normal C57BL/6J control mice and ob/ob model group mice were orally administered with the equal volume solvent. The body weight per week were recorded. The fasting blood-glucose (FBG) was measured by glycemic instrument. The content of TG, TC, HDL-C, LDL-C in serum, and TG and TC content in liver were determined by biochemical method. The liver index was calculated.Results Compared with ob/ob model group, there was no significant change in body weight of mice administered with Maiqi-Jiangtang pill for 10 weeks. Compared with the model group, the low-, medium- dose Maiqi-Jiangtang pill could significantly decrease the FBG (7.43 ± 1.71 mmol/L,7.84 ± 1.09 mmol/L vs.8.95 ± 0.96mmol/L), the high- dose Maiqi-Jiangtang pill could significantly reduce the TG (0.93 ± 0.16 mmol/L vs.1.18 ± 0.26 mmol/L) and LDL-C (2.10 ± 0.51 mmol/L vs.2.56 ± 0.44 mmol/L) content in serum of ob/ob mice (P<0.05), increase the HDL-C/LDL-C ratio (2.40 ± 0.39vs.1.96 ± 0.24) in serum (P<0.01), decrease the liver weight (3.52 ± 0.26 gvs. 3.98 ± 0.35 g) and the liver index (0.063 ± 0.004vs. 0.071 ± 0.006) (P<0.05). Compared with the model group, the low dose Maiqi-Jiangtang pill could also significantly decrease the TG level (0.63 ± 0.25 mmol/gvs. 1.05 ± 0.67 mmol/g) in liver and significantly increase the HDL-C/LDL-C ratio (2.30 ± 0.44vs. 1.96 ± 0.24) in serum (P<0.05).Conclusions The Maiqi-Jiangtang pill can reduce lipid in serum and liver of ob/ob mice while it can decrease the blood glucose, which need to further study its mechanism.

Effect of Tangnaikang on Imbalance Between NE and α1-AT in Spontaneous Type 2 Diabetic Mouse / 中国实验方剂学杂志

Objective: To observe the regulatory effect of Tangnaikang (TNK) on imbalance between neutrophil elastase (NE) and α1-antitrypsin (α1-AT) in ob/ob mice with type 2 diabetes mellitus (T2DM). Method: Thirty-two male SPF ob/ob mice were randomly divided into model group (DM, normal saline) and high-dose TNK group (TNKH, TNK solution 16.04 g·kg-1), middle-dose TNK group (TNKM, TNK solution 8.02 g·kg-1) and low-dose TNK group (TNKL, TNK solution 4.01 g·kg-1). Another 8 C57BL/6J mice were included in normal group (Con, saline). The experiment lasted for four weeks. The general state, body weight (BW) and fasting blood glucose (FBG) of the mice were recorded weekly, the oral glucose tolerance (OGTT) test was performed on the 25th day, the insulin tolerance (ITT) test was performed on the 27th day, and the area under the curve (AUC) was calculated. After the end of the experiment, serum was used to detect the level of fasting insulin (Fins), insulin resistance index (HOMA-IR), total triglyceride (TG), total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), NE and α1-AT. Adipose tissue was used to detect the expressions of NE, α1-AT, phosphor-insulin receptor substrate 1 antibody (p-IRS1) and glucose transporter 4 (GLUT4) proteins. Result: Compared with the Con group, the BW of the ob/ob mice of the model group increased significantly, the glucose and lipid metabolism indexes showed diabetes, the serum and adipose tissue NE increased significantly (Pα1-AT decreased significantly (PPPogtt and AUCITT were significantly decreased (PPα1-AT increased significantly (PPConclusion: TNK can reduce the BW of ob/ob mice, improve glycolipid metabolism, increase α1-AT level, decrease NE level, and regulate IRS1-GLUT4 signaling pathway, which may be one of its mechanisms in improving IR of adipose tissue mediated by neutrophil.

Lean vs. obese mice: the ventral prostate revisited / Ratones magros vs. ratones obesos: revisión de la próstata ventral

Obese mice (C57BL/6J-ob/ob) do not express leptin and develops hyperphagia, decreased energy expenditure, obesity, hyperglycemia, hyperinsulinemia, hypothermia, and infertility. Obesity causes reproductive dysfunction with negative impacts on prostatic structure and fertility. We aimed to compare the structure and molecular aspects of the ventral prostate between of lean and obese (ob/ob) mice. Three months old male lean and obese mice had their prostates dissected and prepared for light microscopy and immunofluorescence. In comparison to the lean mouse, the obese mouse showed a substantial structural modification in the ventral prostate starting with an atrophy of the prostate ventral lobe. Histologically, the acini showed a reduction in size, and in the lumen, we found a mixed secretion PAS positive and negative. Epithelial changes consisted of a hypertrophied acinar epithelium with intraepithelial neoplasia focuses. Also, we observed a marked expression of PCNA and Caspase3 in the epithelium indicating even cellular proliferation as cell death. The stroma showed a high activity of the extracellular matrix remodeling with marked deposition of collagen fibers and smooth muscle cells. Around the ventral region, we observed an increase in the presence of adipose tissue. The expressions of interleukin 6 and tumor necrosis factor alpha were present in the ventral prostate of the obese mice indicating inflammation. In conclusion, obesity negatively modulates prostate in ob/ob mice, directly affecting cellular and structural mechanisms necessary for the maintenance of prostate and reproductive structure.

Los ratones obesos (C57BL / 6J-ob / ob) no expresan leptina y desarrollan hiperfagia, disminución del gasto energético, obesidad, hiperglucemia, hiperinsulinemia, hipotermia e infertilidad. La obesidad causa disfunción reproductiva con impacto negativo sobre la estructura prostática y la fertilidad. El objetivo de nuestro trabajo consistió en comparar la estructura y los aspectos moleculares de la próstata ventral en ratones magros y obesos (ob/ob). Se disecaron las próstatas de ratones machos obesos, de tres meses de edad, y fueron preparadas para visualizarlas por microscopía óptica e inmunofluorescencia. En comparación con el ratón magro, el ratón obeso mostró una sustancial modificación estructural en la próstata ventral comenzando con una atrofia del lóbulo ventral de la próstata. Histológicamente, los acinos mostraron una reducción de tamaño, y en el lumen, encontramos una secreción mixta PAS positiva y negativa. Los cambios epiteliales consistieron en un epitelio acinar hipertrofiado con focos de neoplasia intraepitelial. Además, se observó una marcada expresión de PCNA y Caspase3 en el epitelio, que indica tanto la proliferación celular como la muerte celular. El estroma mostró una alta remodelación de la matriz extracelular con marcada deposición de fibras de colágeno y células de músculo liso. Alrededor de la región ventral, se observó un aumento en la presencia de tejido adiposo. Las expresiones de interleuquina 6 y factor de necrosis tumoral alfa estaban presentes en la próstata ventral de los ratones obesos indicando inflamación. En conclusión, la obesidad modula negativamente la próstata en los ratones ob/ob, afectando directamente los mecanismos celulares y estructurales necesarios para el mantenimiento de la estructura de la próstata y la reproducción.

Protective effect and underlying mechanism of cordycepin on non-alcoholic fatty liver in ob/ob mice / 药学学报

This study is designed to investigate the protective effect and mechanism of cordycepin on nonalcoholic fatty liver in ob/ob mice. Twelve-week-old male ob/ob mice were divided into 5 groups according to their body weight and blood glucose, and C57BL/6J mice were used in the control group. The animals were orally administered with cordycepin for 7 weeks. Body weight and food intake were measured once a week. Blood were collected from ophthalmic venous and biochemical indexes were determined at the 2nd and 4th week. Insulin tolerance test was performed at the 5th week. After 7 weeks of administration, liver tissues were collected to determine the contents of triglycerides and total cholesterol, and pro-inflammatory cytokines. Liver histology was performed by hematoxylin-eosin and oil-red O staining. Total RNA were extracted from liver tissues and the levels of lipid metabolism-related and inflammation-related genes were detected by real time PCR. Cordycepin effectively reduced the blood lipids level and improved liver function. Nevertheless, it did not improve insulin resistance in ob/ob mice. Cordycepin significantly reduced the contents of triglycerides and cholesterol, and the levels of pro-inflammatory cytokines in liver tissues. Moreover, cordycepin remarkably suppressed the expression of genes related to lipids synthesis and inflammation. These results indicate that cordycepin may improve non-alcoholic fatty liver in ob/ob mice, and the underlying mechanism may be associated with decreased expression of genes related to lipids synthesis and inflammation.

Rosiglitazone attenuates cognitive function via altering hippocampal IRS-1/Akt signaling pathways in ob/ob mouse / 中国药理学通报

Aim To identify alteration in key molecular components related to memory formation and insulin signaling in the hippocampus after rosiglitazone was in-jected into the ob/ob mice to test whether cognitive dysfunction was pharmacologically reversed by regula-tion of rosiglitazone. Methods The age-matched mice were divided into three groups ( n=18 ): Saline-trea-ted WT mice ( WT-Saline);Saline-treated ob/ob mice ( ob/ob-Saline) and RSG-treated ob/ob mice ( ob/ob-RSG) through intraperitoneal injection of rosiglitazone ( RSG) . The random glucose levels were measured for 10 days during the intraperitoneal injection period. No-vel object recognition was performed before mice were sacrificed. Western blot was implemented to evaluate the following proteins: BACE1, p-Tau, p-IRS1,IRS1, p-Akt and Akt in hippocampal tissues. The Aβ1-40 levels were detected by ELISA Kit. Results The random blood glucose levels were significantly re-duced in ob/ob-RSG compared with ob/ob-saline. RSG treatment led to an increase in hippocampus-de-pendent cognition of ob/ob mice according to the novel object recognition. The proteins levels of BACE1, p-Tau and Aβ were lowered in RSG-treated ob/ob mice. Furthermore, RSG treatment up-regulated hippocampal p-IRS1/IRS1 and p-Akt/Akt ratio. Conclusion Ros-iglitazone ameliorates cognitive deficits in ob/ob mice through up-regulating insulin signaling pathways in the hippocampus.

Cordyceps militaris alleviates non-alcoholic fatty liver disease in ob/ob mice

BACKGROUND/OBJECTIVES: Non-alcoholic fatty liver disease (NAFLD) is becoming an important public health problem as metabolic syndrome and type 2 diabetes have become epidemic. In this study we investigated the protective effect of Cordyceps militaris (C. militaris) against NAFLD in an obese mouse model. MATERIALS/METHODS: Four-week-old male ob/ob mice were fed an AIN-93G diet or a diet containing 1% C. militaris water extract for 10 weeks after 1 week of adaptation. Serum glucose, insulin, free fatty acid (FFA), alanine transaminase (ALT), and proinflammatory cytokines were measured. Hepatic levels of lipids, glutathione (GSH), and lipid peroxide were determined. RESULTS: Consumption of C. militaris significantly decreased serum glucose, as well as homeostasis model assessment for insulin resistance (HOMA-IR), in ob/ob mice. In addition to lowering serum FFA levels, C. militaris also significantly decreased hepatic total lipids and triglyceride contents. Serum ALT activities and tumor necrosis factor-alpha (TNF-alpha) and interleukin-6 (IL-6) levels were reduced by C. militaris. Consumption of C. militaris increased hepatic GSH and reduced lipid peroxide levels. CONCLUSIONS: These results indicate that C. militaris can exert protective effects against development of NAFLD, partly by reducing inflammatory cytokines and improving hepatic antioxidant status in ob/ob mice.

Exendin-4 Improves Nonalcoholic Fatty Liver Disease by Regulating Glucose Transporter 4 Expression in ob/ob Mice

Exendin-4 (Ex-4), a glucagon-like peptide-1 receptor (GLP-1R) agonist, has been known to reverse hepatic steatosis in ob/ob mice. Although many studies have evaluated molecular targets of Ex-4, its mechanism of action on hepatic steatosis and fibrosis has not fully been determined. In the liver, glucose transporter 4 (GLUT4) is mainly expressed in hepatocytes, endothelial cells and hepatic stellate cells (HSCs). In the present study, the effects of Ex-4 on GLUT4 expression were determined in the liver of ob/ob mice. Ob/ob mice were treated with Ex-4 for 10 weeks. Serum metabolic parameters, hepatic triglyceride levels, and liver tissues were evaluated for hepatic steatosis. The weights of the whole body and liver in ob/ob mice were reduced by long-term Ex-4 treatment. Serum metabolic parameters, hepatic steatosis, and hepatic fibrosis in ob/ob mice were reduced by Ex-4. Particularly, Ex-4 improved hepatic steatosis by enhancing GLUT4 via GLP-1R activation in ob/ob mice. Ex-4 treatment also inhibited hepatic fibrosis by decreasing expression of connective tissue growth factor in HSCs of ob/ob mice. Our data suggest that GLP-1 agonists exert a protective effect on hepatic steatosis and fibrosis in obesity and type 2 diabetes.

Hog millet (Panicum miliaceum L.)-supplemented diet ameliorates hyperlipidemia and hepatic lipid accumulation in C57BL/6J-ob/ob mice

Dietary intake of whole grains reduces the incidence of chronic diseases such as obesity, diabetes, cardiovascular disease, and cancer. In an earlier study, we showed that Panicum miliaceum L. extract (PME) exhibited the highest anti-lipogenic activity in 3T3-L1 cells among extracts of nine different cereal grains tested. In this study, we hypothesized that PME in the diet would lead to weight loss and augmentation of hyperlipidemia by regulating fatty acid metabolism. PME was fed to ob/ob mice at 0%, 0.5%, or 1% (w/w) for 4 weeks. After the experimental period, body weight changes, blood serum and lipid profiles, hepatic fatty acid metabolism-related gene expression, and white adipose tissue (WAT) fatty acid composition were determined. We found that the 1% PME diet, but not the 0.5%, effectively decreased body weight, liver weight, and blood triglyceride and total cholesterol levels (P < 0.05) compared to obese ob/ob mice on a normal diet. Hepatic lipogenic-related gene (PPARalpha, L-FABP, FAS, and SCD1) expression decreased, whereas lipolysis-related gene (CPT1) expression increased in animals fed the 1% PME diet (P < 0.05). Long chain fatty acid content and the ratio of C18:1/C18:0 fatty acids decreased significantly in adipose tissue of animals fed the 1% PME diet (P < 0.05). Serum inflammatory mediators also decreased significantly in animals fed the 1% PME diet compared to those of the ob/ob control group (P < 0.05). These results suggest that PME is useful in the chemoprevention or treatment of obesity and obesity-related disorders.

Exercício físico reduz a hiperglicemia de jejum em camundongos diabéticos através da ativação da AMPK / Physical exercise decreases fasting hyperglycemia in diabetic mice through AMPK activation

INTRODUÇÃO: A deficiência na captação de glicose em tecidos periféricos e o aumento da gliconeogênese hepática são fenômenos fisiopatológicos observados em pacientes diabéticos do tipo 2. O exercício físico é considerado um importante aliado para a melhora do perfil glicêmico em pacientes diabéticos; entretanto, os mecanismos envolvidos nesse processo não estão completamente elucidados. OBJETIVO: Avaliar o papel da proteína AMPK no controle glicêmico em camundongos diabéticos após o exercício físico. MÉTODOS: Durante o jejum, o teste de tolerância à insulina (ITT) e a técnica de Western blot foram combinados para avaliar a homeostase da glicose em camundongos diabéticos (ob/ob e db/db) submetidos a uma única sessão de natação. RESULTADOS: A hiperglicemia de jejum, a severa resistência à insulina e a deficiência na sinalização da via AMPK/ACC no músculo e no fígado observadas nos camundongos diabéticos foram revertidas após a sessão de exercício. A restauração da via AMPK/ACC reduziu a expressão da enzima gliconeogênica PEPCK no fígado e aumentou a translocação do GLUT4 no músculo esquelético. Esses dados apontam que a ativação da via AMPK/ACC induzida pelo exercício físico é importante para a redução da glicemia de jejum em modelos experimentais de diabetes tipo 2. Esses dados abrem novas frentes para o entendimento de como a atividade física controla da homeostase da glicose em pacientes diabéticos.

INTRODUCTION: The deficiency in glucose uptake in peripheral tissues and increased hepatic gluconeogenesis are physiopathological phenomena observed in type 2 diabetes patients. Physical exercise plays an important role in the improvement of glycemic profile in diabetic patients; however, the mechanisms involved in these processes have not been fully elucidated. OBJECTIVE: to assess the role of AMPK protein in the glycemic control of diabetic mice after exercise. METHODS: During fasting condition, the insulin tolerance test (ITT) and Western blot technique, were combined to assess the glucose homeostasis in diabetic mice (ob/ob and db/db) after a single swimming session. RESULTS: Fasting hyperglycemia, severe insulin resistance and deficiency in the AMPK/ACC signaling in muscle and liver observed in the diabetic mice were reversed after the exercise session. The restoration of AMPK/ACC signaling reduced the expression of the gluconeogenic enzyme, PEPCK in the liver, and increased the translocation of GLUT4 in the skeletal muscle. These data indicate that the activation of AMPK/ACC pathway induced by physical exercise is important to reduce fasting glucose levels in experimental models of type 2 diabetes. These data open new insights for determination of physical activity control on the glucose homeostasis in diabetic patients.

Anti-obesity activity of diglyceride containing conjugated linoleic acid in C57BL/6J ob/ob mice

This study was to investigate the anti-obesity effects of diglyceride (DG)-conjugated linoleic acid (CLA) containing 22% CLA as fatty acids in C57BL/6J ob/ob male mice. There were four experimental groups including vehicle control, DG, CLA, and DG-CLA. The test solutions of 750 mg/kg dose were orally administered to the mice everyday for 5 weeks. CLA treatments significantly decreased mean body weight in the obese mice throughout the experimental period compared to the control (p < 0.01). All test solutions significantly decreased the levels of triglyceride, glucose and free fatty acids in the serum compared with control (p < 0.05). The levels of total cholesterol were also significantly reduced in DG and DG-CLA groups compared with the control group (p < 0.05). CLA significantly decreased weights of renal and epididymal fats compared with the control (p < 0.05). DG and DG-CLA also significantly decreased the epididymal fat weights compared with the control (p < 0.05). A remarkable decrease in the number of lipid droplets and fat globules was observed in the livers of mice treated with DG, CLA, and DG-CLA compared to control. Treatments of DG and CLA actually increased the expression of peroxisome proliferator-activated receptor gamma. These results suggest that DG-CLA containing 22% CLA have a respectable anti-obesity effect by controlling serum lipids and fat metabolism.