scholarly journals Autophagy is involved in adipogenic differentiation by repressesing proteasome-dependent PPARγ2 degradation

2013 ◽  
Vol 305 (4) ◽  
pp. E530-E539 ◽  
Author(s):  
Chongben Zhang ◽  
Yingke He ◽  
Mitsuhara Okutsu ◽  
Lai Chun Ong ◽  
Yi Jin ◽  
...  
Keyword(s):  
High Fat Diet ◽  
Animal Studies ◽  
Adipogenic Differentiation ◽  
Daily Injection ◽  
Related Gene ◽  
High Fat ◽  
Pharmacological Interventions ◽  
Diet Induced Obesity

Animal studies have shown that autophagy is essential in the process of obesity. Here, we performed daily injection of the autophagy inhibitor chloroquine (CQ) in mice and found that systemic administration of CQ blocks high-fat diet-induced obesity. To investigate the potential underlying molecular mechanism, we employed genetic and pharmacological interventions in cultured preadipocytes to investigate the role of autophagy in the control of the expression of the adipogenic regulator peroxisome proliferatior-activated receptor-γ (PPARγ). We show that adipogenic differentiation of 3T3-L1 preadipocytes is associated with activation of autophagy and increased PPARγ2 protein level. Treatment with CQ, shRNA-mediated knockdown, or genetic engineering-induced deletion of autophagy-related gene 5 (Atg5) promoted proteasome-dependent PPARγ2 degradation and attenuated adipogenic differentiation. Therefore, activated autophagy increases PPARγ2 stability and promotes adipogenic differentiation, and inhibition of autophagy may prevent high-fat diet-induced obesity and the consequential type 2 diabetes.

scholarly journals Role of Muscle c-Jun NH2-Terminal Kinase 1 in Obesity-Induced Insulin Resistance

2009 ◽  
Vol 30 (1) ◽  
pp. 106-115 ◽  
Author(s):  
Guadalupe Sabio ◽  
Norman J. Kennedy ◽  
Julie Cavanagh-Kyros ◽  
Dae Young Jung ◽  
Hwi Jin Ko ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Adipose Tissue ◽  
High Fat Diet ◽  
Wild Type ◽  
High Fat ◽  
Akt Activation ◽  
Peripheral Insulin Resistance ◽  
Diet Induced Obesity

ABSTRACT Obesity caused by feeding of a high-fat diet (HFD) is associated with an increased activation of c-Jun NH2-terminal kinase 1 (JNK1). Activated JNK1 is implicated in the mechanism of obesity-induced insulin resistance and the development of metabolic syndrome and type 2 diabetes. Significantly, Jnk1 − / − mice are protected against HFD-induced obesity and insulin resistance. Here we show that an ablation of the Jnk1 gene in skeletal muscle does not influence HFD-induced obesity. However, muscle-specific JNK1-deficient (MKO) mice exhibit improved insulin sensitivity compared with control wild-type (MWT) mice. Thus, insulin-stimulated AKT activation is suppressed in muscle, liver, and adipose tissue of HFD-fed MWT mice but is suppressed only in the liver and adipose tissue of MKO mice. These data demonstrate that JNK1 in muscle contributes to peripheral insulin resistance in response to diet-induced obesity.

scholarly journals Polyphenols as Prebiotics in the Management of High-Fat Diet-Induced Obesity: A Systematic Review of Animal Studies

Foods ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 299
Author(s):  
Mohanambal Moorthy ◽  
Usha Sundralingam ◽  
Uma D. Palanisamy
Keyword(s):  
Systematic Review ◽  
Body Weight ◽  
High Fat Diet ◽  
Animal Studies ◽  
Literature Search ◽  
Web Of Science ◽  
Preclinical Studies ◽  
High Fat ◽  
Diet Induced Obesity

Obesity is a disease growing at an alarming rate and numerous preclinical studies have proven the role of polyphenols in managing this disease. This systematic review explores the prebiotic effect of polyphenols in the management of obesity among animals fed on a high-fat diet. A literature search was carried out in PubMed, Scopus, CINAHL, Web of Science, and Embase databases following the PRISMA guidelines. Forty-four studies reported a significant reduction in obesity-related parameters. Most notably, 83% of the studies showed a decrease in either body weight/visceral adiposity/plasma triacylglyceride. Furthermore, 42 studies reported a significant improvement in gut microbiota (GM), significantly affecting the genera Akkermansia, Bacteroides, Blautia, Roseburia, Bifidobacteria, Lactobacillus, Alistipes, and Desulfovibrio. Polyphenols’ anti-obesity, anti-hyperglycaemic, and anti-inflammatory properties were associated with their ability to modulate GM. This review supports the notion of polyphenols as effective prebiotics in ameliorating HFD-induced metabolic derangements in animal models.

scholarly journals RGC32 deficiency protects against high-fat diet-induced obesity and insulin resistance in mice

2014 ◽  
Vol 224 (2) ◽  
pp. 127-137 ◽  
Author(s):  
Xiao-Bing Cui ◽  
Jun-Na Luan ◽  
Jianping Ye ◽  
Shi-You Chen
Keyword(s):  
Insulin Resistance ◽  
Type 2 Diabetes ◽  
Adipose Tissue ◽  
High Fat Diet ◽  
Tolerance Test ◽  
High Fat ◽  
Diet Induced Obesity

Obesity is an important independent risk factor for type 2 diabetes, cardiovascular diseases and many other chronic diseases. Adipose tissue inflammation is a critical link between obesity and insulin resistance and type 2 diabetes and a contributor to disease susceptibility and progression. The objective of this study was to determine the role of response gene to complement 32 (RGC32) in the development of obesity and insulin resistance. WT and RGC32 knockout (Rgc32−/− (Rgcc)) mice were fed normal chow or high-fat diet (HFD) for 12 weeks. Metabolic, biochemical, and histologic analyses were performed. 3T3-L1 preadipocytes were used to study the role of RGC32 in adipocytes in vitro. Rgc32−/− mice fed with HFD exhibited a lean phenotype with reduced epididymal fat weight compared with WT controls. Blood biochemical analysis and insulin tolerance test showed that RGC32 deficiency improved HFD-induced dyslipidemia and insulin resistance. Although it had no effect on adipocyte differentiation, RGC32 deficiency ameliorated adipose tissue and systemic inflammation. Moreover, Rgc32−/− induced browning of adipose tissues and increased energy expenditure. Our data indicated that RGC32 plays an important role in diet-induced obesity and insulin resistance, and thus it may serve as a potential novel drug target for developing therapeutics to treat obesity and metabolic disorders.

scholarly journals High-Fat Diet and Age-Dependent Effects of IgA-Bearing Cell Populations in the Small Intestinal Lamina Propria in Mice

2021 ◽  
Vol 22 (3) ◽  
pp. 1165
Author(s):  
Yuta Sakamoto ◽  
Masatoshi Niwa ◽  
Ken Muramatsu ◽  
Satoshi Shimo
Keyword(s):  
Immune Function ◽  
Lamina Propria ◽  
High Fat Diet ◽  
Immunoglobulin A ◽  
Immune Functions ◽  
High Fat ◽  
Intestinal Villi ◽  
Diet Induced Obesity ◽  
Obesity And Diabetes

Several studies highlighted that obesity and diabetes reduce immune function. However, changes in the distribution of immunoglobins (Igs), including immunoglobulin-A (IgA), that have an important function in mucosal immunity in the intestinal tract, are unclear. This study aimed to investigate the impaired immune functions in the context of a diet-induced obese murine model via the assessment of the Igs in the intestinal villi. We used mice fed a high-fat diet (HFD) from four to 12 or 20 weeks of age. The distributions of IgA, IgM, and IgG1 were observed by immunohistochemistry. Interestingly, we observed that IgA was immunolocalized in many cells of the lamina propria and that immunopositive cells increased in mice aged 12 to 20 weeks. Notably, mice fed HFD showed a reduced number of IgA-immunopositive cells in the intestinal villi compared to those fed standard chow. Of note, the levels of IgM and IgG1 were also reduced in HFD fed mice. These results provide insights into the impaired mucosal immune function arising from diet-induced obesity and type 2 diabetes.

Ameliorative effect of selegiline in high fat diet induced obesity rat model: Possible role of dopaminergic pathway

2020 ◽  
Vol 20 ◽  
pp. 100301
Author(s):  
Amit Goyal ◽  
Ankita Sharma ◽  
Deepika Sharma ◽  
Tapan Behl ◽  
Anjoo Kamboj ◽  
...  
Keyword(s):  
Rat Model ◽  
High Fat Diet ◽  
High Fat ◽  
Diet Induced Obesity ◽  
Dopaminergic Pathway ◽  
Ameliorative Effect

scholarly journals Role of TNF-α and FGF-2 in the Fracture Healing Disorder of Type 2 Diabetes Model Induced by High Fat Diet Followed by Streptozotocin

2020 ◽  
Vol Volume 13 ◽  
pp. 2279-2288
Author(s):  
Heqing Huang ◽  
Ling Luo ◽  
Zhitao Liu ◽  
Yan Li ◽  
Zhaochen Tong ◽  
...  
Keyword(s):  
Type 2 Diabetes ◽  
Fracture Healing ◽  
High Fat Diet ◽  
High Fat ◽  
Diabetes Model ◽  
Tnf Α

scholarly journals Hypertrophic cardiomyopathy in high-fat diet-induced obesity: role of suppression of forkhead transcription factor and atrophy gene transcription

2008 ◽  
Vol 295 (3) ◽  
pp. H1206-H1215 ◽  
Author(s):  
Cindy X. Fang ◽  
Feng Dong ◽  
D. Paul Thomas ◽  
Heng Ma ◽  
Leilei He ◽  
...  
Keyword(s):  
Transcription Factor ◽  
Palmitic Acid ◽  
High Fat Diet ◽  
Weight Control ◽  
Dominant Negative ◽  
High Fat ◽  
Forkhead Transcription Factor ◽  
Diet Induced Obesity ◽  
Intracellular Ca

Cellular hypertrophy is regulated by coordinated pro- and antigrowth machineries. Foxo transcription factors initiate an atrophy-related gene program to counter hypertrophic growth. This study was designed to evaluate the role of Akt, the forkhead transcription factor Foxo3a, and atrophy genes muscle-specific RING finger (MuRF)-1 and atrogin-1 in cardiac hypertrophy and contractile dysfunction associated with high-fat diet-induced obesity. Mice were fed a low- or high-fat diet for 6 mo along with a food-restricted high-fat weight control group. Echocardiography revealed decreased fractional shortening and increased end-systolic diameter and cardiac hypertrophy in high-fat obese but not in weight control mice. Cardiomyocytes from high-fat obese but not from weight control mice displayed contractile and intracellular Ca2+ defects including depressed maximal velocity of shortening/relengthening, prolonged duration of shortening/relengthening, and reduced intracellular Ca2+ rise and clearance. Caspase activities were greater in high-fat obese but not in weight control mouse hearts. Western blot analysis revealed enhanced basal Akt and Foxo3a phosphorylation and reduced insulin-stimulated phosphorylation of Akt and Foxo3a without changes in total protein expression of Akt and Foxo3a in high-fat obese hearts. RT-PCR and immunoblotting results displayed reduced levels of the atrogens atrogin-1 and MuRF-1, the upregulated hypertrophic markers GATA4 and ciliary neurotrophic factor receptor-α, as well as the unchanged calcineurin and proteasome ubiquitin in high-fat obese mouse hearts. Transfection of H9C2 myoblast cells with dominant-negative Foxo3a adenovirus mimicked palmitic acid (0.8 mM for 24 h)-induced GATA4 upregulation without an additive effect. Dominant-negative Foxo3a-induced upregulation of pAkt and repression of phosphatase and tensin homologue were abrogated by palmitic acid. These results suggest a cardiac hypertrophic response in high-fat diet-associated obesity at least in part through inactivation of Foxo3a by the Akt pathway.

scholarly journals Role of human pregnane X receptor in high fat diet-induced obesity in pre-menopausal female mice

2014 ◽  
Vol 89 (3) ◽  
pp. 399-412 ◽  
Author(s):  
Krisstonia Spruiell ◽  
Dominique Z. Jones ◽  
John M. Cullen ◽  
Emmanuel M. Awumey ◽  
Frank J. Gonzalez ◽  
...  
Keyword(s):  
High Fat Diet ◽  
Pregnane X Receptor ◽  
High Fat ◽  
Female Mice ◽  
Diet Induced Obesity
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