scholarly journals Obesity induced by high-fat diet promotes insulin resistance in the ovary

2010 ◽  
Vol 206 (1) ◽  
pp. 65-74 ◽  
Author(s):  
Eliana H Akamine ◽  
Anderson C Marçal ◽  
João Paulo Camporez ◽  
Mara S Hoshida ◽  
Luciana C Caperuto ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Signaling Pathway ◽  
Insulin Signaling ◽  
High Fat Diet ◽  
Ovarian Function ◽  
Polycystic Ovary ◽  
Insulin Signaling Pathway ◽  
Female Rats ◽  
High Fat ◽  
Obese Rats

Besides the effects on peripheral energy homeostasis, insulin also has an important role in ovarian function. Obesity has a negative effect on fertility, and may play a role in the development of the polycystic ovary syndrome in susceptible women. Since insulin resistance in the ovary could contribute to the impairment of reproductive function in obese women, we evaluated insulin signaling in the ovary of high-fat diet-induced obese rats. Female Wistar rats were submitted to a high-fat diet for 120 or 180 days, and the insulin signaling pathway in the ovary was evaluated by immunoprecipitation and immunoblotting. At the end of the diet period, we observed insulin resistance, hyperinsulinemia, an increase in progesterone serum levels, an extended estrus cycle, and altered ovarian morphology in obese female rats. Moreover, in female obese rats treated for 120 days with the high-fat diet, the increase in progesterone levels occurred together with enhancement of LH levels. The ovary from high-fat-fed female rats showed a reduction in the insulin receptor substrate/phosphatidylinositol 3-kinase/AKT intracellular pathway, associated with an increase in FOXO3a, IL1B, and TNFα protein expression. These changes in the insulin signaling pathway may have a role in the infertile state associated with obesity.

Chlorella modulates insulin signaling pathway and prevents high-fat diet-induced insulin resistance in mice

Life Sciences ◽  
2014 ◽  
Vol 95 (1) ◽  
pp. 45-52 ◽  
Author(s):  
Juliana Falcato Vecina ◽  
Alexandre Gabarra Oliveira ◽  
Tiago Gomes Araujo ◽  
Sueli Regina Baggio ◽  
Cristiane Okuda Torello ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Signaling Pathway ◽  
Insulin Signaling ◽  
High Fat Diet ◽  
Insulin Signaling Pathway ◽  
High Fat

scholarly journals Resveratrol improves skeletal muscle insulin resistance through downregulating lncRNA NONMMUT044897.2

2021 ◽  
Author(s):  
Zhihong Liu ◽  
Zhimei Zhang ◽  
Guangyao Song ◽  
Xing Wang ◽  
Hanying Xing ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Skeletal Muscle ◽  
Signaling Pathway ◽  
Insulin Signaling ◽  
High Fat Diet ◽  
High Throughput Sequencing ◽  
Insulin Signaling Pathway ◽  
Cytokine Signaling ◽  
Mice Model ◽  
High Fat

Abstract Background: Long non-coding RNA (lncRNA) has proved to be crucial factors in the progression of insulin resistance (IR). Resveratrol (RSV) exhibits promising therapeutic potential for the IR. Nonetheless, whether RSV could influence the expression of lncRNAs and the interaction mechanisms in IR remain unclear.Methods: We conducted high-throughput sequencing to detect the lncRNAs and mRNAs expression signatures and the co-expression network of lncRNAs and mRNAs in skeletal muscle after a high-fat diet (HFD)-induced IR mice model with or without RSV treatment, including hierarchical clustering, gene enrichment and gene co-expression networks analysis. Highly differentially expressed lncRNAs were selected and validated by RT-qPCR. Finally, the biological functions of the selected lncRNAs were investigated by silencing expressing the target genes through lentivirus transfection in C2C12 mouse myotubes cells.Results: We revealed that 338 mRNAs and 629 lncRNAs whose expression in skeletal muscle after a high-fat diet (HFD)-induced IR mice model was reversed by RSV treatment. Gene Ontology and Kyoto encyclopedia of genes and genomes databases indicated that the differential expression mRNAs modulate the insulin signaling pathway. After validating randomly selected lncRNAs via RT-qPCR, we found that lncRNA (NONMMUT044897.2) and Suppressor of Cytokine Signaling 1 (SOCS1) were up-regulated in the HFD group, and reversed by RSV treatment. Additionally, NONMMUT044897.2 was validated to function as a ceRNA of microRNA (miR)-7051-5p and SOCS1 was confirmed as a target for miR‑7051-5p. We further performed lentivirus transfection to knockdown NONMMUT044897.2 in vitro and found that NONMMUT044897.2 silence inactivated SOCS1 and promoted the insulin signaling pathway. Importantly, RSV could mimic the effects of silencing NONMMUT044897.2.Conclusion: Our study revealed that resveratrol improves skeletal muscle IR might be via regulation of NONMUT044897.2.

scholarly journals Influence ofOreocnide integrifolia(Gaud.) Miq on IRS-1, Akt and Glut-4 in Fat-Fed C57BL/6J Type 2 Diabetes Mouse Model

2011 ◽  
Vol 2011 ◽  
pp. 1-9 ◽  
Author(s):  
Ansarullah ◽  
Selvaraj Jayaraman ◽  
Anandwardhan A. Hardikar ◽  
A. V. Ramachandran
Keyword(s):  
Signaling Pathway ◽  
Insulin Signaling ◽  
High Fat Diet ◽  
Therapeutic Potential ◽  
Insulin Signaling Pathway ◽  
High Fat ◽  
Isolated Pancreatic Islets ◽  
Glut 4

Oreocnide integrifolia(OI) leaves are used as folklore medicine by the people of northeast India to alleviate diabetic symptoms. Preliminary studies revealed hypoglycemic and hypolipidemic potentials of the aqueous leaf extract. The present study was carried out to evaluate whether the OI extract induces insulin secretionin vivoandin vitroand also whether it is mediated through the insulin-signaling pathway. The experimental set-up consisted of three groups of C57BL/6J mice strain: (i) control animals fed with standard laboratory diet, (ii) diabetic animals fed with a high-fat diet for 24 weeks and (iii) extract-supplemented animals fed with 3% OI extract along with high-fat diet for 24 weeks. OI-extract supplementation lowered adiposity and plasma glucose and insulin levels. Immunoblot analysis of IRS-1, Akt and Glut-4 protein expressions in muscles of extract-supplemented animals revealed that glucoregulation was mediated through the insulin-signaling pathway. Moreover, immunostaining of pancreas revealed increased insulin immunopositive cells in OI-extract-treated animals. In addition, the insulin secretogogue ability of the OI extract was demonstrated when challenged with high glucose concentration using isolated pancreatic isletsin vitro. Overall, the present study demonstrates the possible mechanism of glucoregulation of OI extract suggestive of its therapeutic potential for the management of diabetes mellitus.

scholarly journals Effects of Distinct n-6 to n-3 Polyunsaturated Fatty Acid Rations on Insulin Resistant and AD-like Phenotypes in High-Fat Diets-Fed APP/PS1 Transgenic Mice

2021 ◽  
Author(s):  
Xiaojun Ma ◽  
Yujie Guo ◽  
Pengfei Li ◽  
Jingjing Xu ◽  
Shengqi Dong ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Fatty Acid ◽  
Protein Expression ◽  
Signaling Pathway ◽  
Inflammatory Cytokines ◽  
Insulin Signaling ◽  
High Fat Diet ◽  
High Fat ◽  
Pufa Ratio ◽  
Pro Inflammatory Cytokines

Abstract Background: Type 2 diabetes mellitus (T2DM) and Alzheimer’s disease (AD) are two prevalent diseases with comparable pathophysiological features and genetic predisposition. Polyunsaturated fatty acids (PUFAs) are essential in maintaining normal brain function. However, little is known about the impact of dietary n-6/n-3 PUFA ratio on AD-like pathology, especially in high-fat diet (HFD)-fed AD model mice. Methods: In the present study, the APP/PS1 mice were treated with 60% HFD for 3.5 months to induced insulin resistance. After that, 45% HFD with different n-6/n-3 PUFA ratios (n-6/n-3=1:1, 5:1 or 16:1) was applied for additional 3.5 months treatment. Following the dietary intervention, the behavior of mice was observed using the Water maze. Following behavioral testing, the animals were euthanized, and serum and tissue samples were collected for biochemical, histological and pathological analyses and evaluation. Cortical fatty acid profile was measured by gas chromatography. Western Blot and immunohistochemistry methods were used to detect protein expression of molecules related to AD pathology and insulin signaling pathway(s) in the brain sample tissues. Immunofluorescence assay was used to uncover the expression and migration of NF-κB in the cortex. qPCR method was applied to determine the gene expression of cortical pro-inflammatory cytokines.Results: HFD caused insulin resistance, increased serum IL-6 and TNF-α level, elevated cortical soluble Aβ1-40, Aβ1-42 content, and increased brain n-6/n-3 PUFAs ratio in APP/PS1 mice. Increased APP and BACE1 protein expression and p-IR/IR ratio, but decreased pro-inflammatory cytokines mRNA expression was observed in the cortex from 60% HFD-fed APP/PS1 mice. N-3 PUFAs rich diet (n-6/n-3=1:1) relieved insulin resistance and hyperlipidemia induced by 60% HFD. Cortical soluble Aβ1-40 and Aβ1-42 contents, the expression of cortical APP, GLUT3, insulin metabolism related molecules, and NF-κB pathway downstream pro-inflammatory cytokines showed a dietary n-6/n-3 PUFAs ratio-dependent way, indicating that dietary n-6/n-3 PUFA ratio plays a critical role in modifying the responses of serum inflammatory cytokine, AD pathology, cortical n-6/n-3 PUFAs ratio, insulin signaling and neuroinflammation to HFD treatment.Conclusion: Dietary n-6/n-3 PUFA ratio play an important role in modifying AD pathophysiology, insulin signaling pathway, and neuro-inflammation response to high fat diet treatment in brain.

The insulin-signaling pathway of the pancreatic islet is impaired in adult mice offspring of mothers fed a high-fat diet

Nutrition ◽  
2016 ◽  
Vol 32 (10) ◽  
pp. 1138-1143 ◽  
Author(s):  
Isabele Bringhenti ◽  
Fernanda Ornellas ◽  
Carlos Alberto Mandarim-de-Lacerda ◽  
Marcia Barbosa Aguila
Keyword(s):  
Signaling Pathway ◽  
Pancreatic Islet ◽  
Insulin Signaling ◽  
High Fat Diet ◽  
Insulin Signaling Pathway ◽  
High Fat ◽  
Adult Mice

scholarly journals Salidroside Modulates Insulin Signaling in a Rat Model of Nonalcoholic Steatohepatitis

2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Hongshan Li ◽  
Hao Ying ◽  
Airong Hu ◽  
Dezhou Li ◽  
Yaoren Hu
Keyword(s):  
Signaling Pathway ◽  
Rat Model ◽  
Insulin Signaling ◽  
Nonalcoholic Steatohepatitis ◽  
High Fat Diet ◽  
Metabolic Diseases ◽  
Insulin Signaling Pathway ◽  
Hepatic Tissue ◽  
Therapeutic Effects ◽  
High Fat

A growing body of evidence has shown the beneficial effects of salidroside in cardiovascular and metabolic diseases. This study aimed to evaluate the therapeutic effects of salidroside on nonalcoholic steatohepatitis (NASH) in rats and explore the underlying mechanisms related to insulin signaling. A rat model of NASH was developed by high-fat diet for 14 weeks. From week 9 onward, the treatment group received oral salidroside (4.33 mg/kg) daily for 6 weeks. Salidroside effectively attenuated steatosis and vacuolation of hepatic tissue, with a dramatic decrease in liver triglycerides and free fatty acid levels (P < 0.01). Dysregulation of FINS, FBG, HOMA-IR, ALT, and AST in serum was ameliorated with salidroside treatment (P < 0.01). In the liver, salidroside induced significant increases in key molecules in the insulin signaling pathway, such as phosphorylated insulin receptor substrate 1 (IRS1), phosphoinositide 3-kinase (PI3K), and protein kinase B (PKB), with a significant decrease in SREBP-1c levels (P < 0.01). Therefore, salidroside effectively protected rats from high-fat-diet-induced NASH, which may be partially attributed to its effects on the hepatic insulin signaling pathway.

scholarly journals Local Cortisol Elevation Contributes to Endometrial Insulin Resistance in Polycystic Ovary Syndrome

2018 ◽  
Vol 103 (7) ◽  
pp. 2457-2467 ◽  
Author(s):  
Jia Qi ◽  
Wangsheng Wang ◽  
Qinling Zhu ◽  
Yaqiong He ◽  
Yao Lu ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Polycystic Ovary Syndrome ◽  
Glucose Uptake ◽  
Signaling Pathway ◽  
Insulin Signaling ◽  
Glucose Transporter ◽  
Polycystic Ovary ◽  
Implantation Rate ◽  
Insulin Signaling Pathway ◽  
Ovary Syndrome

Abstract Context Endometrial insulin resistance (IR) may account for the endometrial dysfunction in polycystic ovary syndrome (PCOS). The underlying mechanism remains to be elucidated. Objective To investigate whether the abundance of 11β-hydroxysteroid dehydrogenases (11β-HSDs) 1 and 2 and cortisol as well as the insulin signaling pathway are altered in PCOS endometrium and to clarify the relationship between endometrial IR and local cortisol. Design We measured cortisol and cortisone concentrations, 11β-HSD1 and 11β-HSD2, and core insulin signaling molecules in endometrial biopsies collected from non-PCOS and PCOS with or without IR patients on the seventh day after human chorionic gonadotropin injection. We also studied the effects of cortisol on glucose uptake and the insulin signaling pathway in primary cultured endometrial epithelial cells (EECs). Results The cortisol concentration was elevated, whereas 11β-HSD2 expression was diminished in endometrial biopsies obtained from PCOS with IR patients compared with those from non-PCOS and PCOS without IR patients. The implantation rate was relatively impaired and the endometrial insulin signaling pathway was defective in PCOS with IR patients. In addition, cortisol attenuated insulin-stimulated glucose uptake in EECs, which was mediated by inhibition of Akt phosphorylation and glucose transporter type 4 translocation via induction of phosphatase and tensin homolog deleted on chromosome ten (PTEN). Conclusions Decreased oxidation of cortisol and defects of insulin signaling in endometrium were observed in PCOS with IR patients. The excessive cortisol level, derived from the reduction of 11β-HSD2, might contribute to the development of endometrial IR by inhibiting the insulin signaling pathway via induction of PTEN expression in EECs.

Sign in / Sign up

Export Citation Format

Share Document