Metabolic dysfunction in female mice with disruption of 5α-reductase 1

5α-Reductases irreversibly catalyse A-ring reduction of pregnene steroids, including glucocorticoids and androgens. Genetic disruption of 5α-reductase 1 in male mice impairs glucocorticoid clearance and predisposes to glucose intolerance and hepatic steatosis upon metabolic challenge. However, it is unclear whether this is driven by changes in androgen and/or glucocorticoid action. Female mice with transgenic disruption of 5α-reductase 1 (5αR1-KO) were studied, representing a ‘low androgen’ state. Glucocorticoid clearance and stress responses were studied in mice aged 6 months. Metabolism was assessed in mice on normal chow (aged 6 and 12 m) and also in a separate cohort following 1-month high-fat diet (aged 3 m). Female 5αR1-KO mice had adrenal suppression (44% lower AUC corticosterone after stress), and upon corticosterone infusion, accumulated hepatic glucocorticoids (~27% increased corticosterone). Female 5αR1-KO mice aged 6 m fed normal chow demonstrated insulin resistance (~35% increased area under curve (AUC) for insulin upon glucose tolerance testing) and hepatic steatosis (~33% increased hepatic triglycerides) compared with controls. This progressed to obesity (~12% increased body weight) and sustained insulin resistance (~38% increased AUC insulin) by age 12 m. Hepatic transcript profiles supported impaired lipid β-oxidation and increased triglyceride storage. Female 5αR1-KO mice were also predisposed to develop high-fat diet-induced insulin resistance. Exaggerated predisposition to metabolic disorders in female mice, compared with that seen in male mice, after disruption of 5αR1 suggests phenotypic changes may be underpinned by altered metabolism of glucocorticoids rather than androgens.

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Disruption of CRTC1 and CRTC2 in Sim1 cells strongly increases high-fat diet intake in female mice but has a modest impact on male mice

PLoS ONE ◽

10.1371/journal.pone.0262577 ◽

2022 ◽

Vol 17 (1) ◽

pp. e0262577

Author(s):

Jin Tanaka ◽

Fuka Ishikawa ◽

Tomoki Jinno ◽

Motoki Miyakita ◽

Haruka Miyamori ◽

...

Keyword(s):

Energy Metabolism ◽

High Fat Diet ◽

Chow Diet ◽

Male Mice ◽

High Fat ◽

Double Knockout ◽

Female Mice ◽

Normal Chow ◽

The Brain ◽

Regulate Gene

cAMP responsive element binding protein (CREB)-regulated transcription coactivators (CRTCs) regulate gene transcription in response to an increase in intracellular cAMP or Ca2+ levels. To date, three isoforms of CRTC have been identified in mammals. All CRTCs are widely expressed in various regions of the brain. Numerous studies have shown the importance of CREB and CRTC in energy homeostasis. In the brain, the paraventricular nucleus of the hypothalamus (PVH) plays a critical role in energy metabolism, and CRTC1 and CRTC2 are highly expressed in PVH neuronal cells. The single-minded homolog 1 gene (Sim1) is densely expressed in PVH neurons and in some areas of the amygdala neurons. To determine the role of CRTCs in PVH on energy metabolism, we generated mice that lacked CRTC1 and CRTC2 in Sim1 cells using Sim-1 cre mice. We found that Sim1 cell-specific CRTC1 and CRTC2 double-knockout mice were sensitive to high-fat diet (HFD)-induced obesity. Sim1 cell-specific CRTC1 and CRTC2 double knockout mice showed hyperphagia specifically for the HFD, but not for the normal chow diet, increased fat mass, and no change in energy expenditure. Interestingly, these phenotypes were stronger in female mice than in male mice, and a weak phenotype was observed in the normal chow diet. The lack of CRTC1 and CRTC2 in Sim1 cells changed the mRNA levels of some neuropeptides that regulate energy metabolism in female mice fed an HFD. Taken together, our findings suggest that CRTCs in Sim1 cells regulate gene expression and suppress excessive fat intake, especially in female mice.

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Chlorogenic Acid Improves High Fat Diet-Induced Hepatic Steatosis and Insulin Resistance in Mice

Pharmaceutical Research ◽

10.1007/s11095-014-1526-9 ◽

2014 ◽

Vol 32 (4) ◽

pp. 1200-1209 ◽

Cited By ~ 91

Author(s):

Yongjie Ma ◽

Mingming Gao ◽

Dexi Liu

Keyword(s):

Insulin Resistance ◽

Chlorogenic Acid ◽

Hepatic Steatosis ◽

High Fat Diet ◽

High Fat

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Thrombospondin 1 Mediates High-Fat Diet-Induced Muscle Fibrosis and Insulin Resistance in Male Mice

Endocrinology ◽

10.1210/en.2013-1587 ◽

2013 ◽

Vol 154 (12) ◽

pp. 4548-4559 ◽

Cited By ~ 43

Author(s):

Mayumi Inoue ◽

Yibin Jiang ◽

Richard H. Barnes ◽

Masakuni Tokunaga ◽

Gabriel Martinez-Santibañez ◽

...

Keyword(s):

Insulin Resistance ◽

High Fat Diet ◽

Skeletal Muscles ◽

Matrix Protein ◽

Extracellular Matrix Protein ◽

Male Mice ◽

High Fat ◽

Adipose Tissues ◽

Early Stages ◽

Thrombospondin 1

Thrombospondin 1 (THBS1 or TSP-1) is a circulating glycoprotein highly expressed in hypertrophic visceral adipose tissues of humans and mice. High-fat diet (HFD) feeding induces the robust increase of circulating THBS1 in the early stages of HFD challenge. The loss of Thbs1 protects male mice from diet-induced weight gain and adipocyte hypertrophy. Hyperinsulinemic euglycemic clamp study has demonstrated that Thbs1-null mice are protected from HFD-induced insulin resistance. Tissue-specific glucose uptake study has revealed that the insulin-sensitive phenotype of Thbs1-null mice is mostly mediated by skeletal muscles. Further assessments of the muscle phenotype using RNA sequencing, quantitative PCR, and histological studies have demonstrated that Thbs1-null skeletal muscles are protected from the HFD-dependent induction of Col3a1 and Col6a1, coupled with a new collagen deposition. At the same time, the Thbs1-null mice display a better circadian rhythm and higher amplitude of energy expenditure with a browning phenotype in sc adipose tissues. These results suggest that THBS1, which circulates in response to a HFD, may induce insulin resistance and fibrotic tissue damage in skeletal muscles as well as the de-browning of sc adipose tissues in the early stages of a HFD challenge. Our study may shed new light on the pathogenic role played by a circulating extracellular matrix protein in the cross talk between adipose tissues and skeletal muscles during obesity progression.

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Estrogens Protect against High-Fat Diet-Induced Insulin Resistance and Glucose Intolerance in Mice

Endocrinology ◽

10.1210/en.2008-0971 ◽

2009 ◽

Vol 150 (5) ◽

pp. 2109-2117 ◽

Cited By ~ 244

Author(s):

Elodie Riant ◽

Aurélie Waget ◽

Haude Cogo ◽

Jean-François Arnal ◽

Rémy Burcelin ◽

...

Keyword(s):

Insulin Resistance ◽

Adipose Tissue ◽

Glucose Intolerance ◽

High Fat Diet ◽

Chow Diet ◽

High Fat ◽

Normal Chow ◽

Visceral Adipose ◽

Deficient Mice ◽

Normal Chow Diet

Although corroborating data indicate that estrogens influence glucose metabolism through the activation of the estrogen receptor α (ERα), it has not been established whether this pathway could represent an effective therapeutic target to fight against metabolic disturbances induced by a high-fat diet (HFD). To this end, we first evaluated the influence of chronic 17β-estradiol (E2) administration in wild-type ovariectomized mice submitted to either a normal chow diet or a HFD. Whereas only a modest effect was observed in normal chow diet-fed mice, E2 administration exerted a protective effect against HFD-induced glucose intolerance, and this beneficial action was abolished in ERα-deficient mice. Furthermore, E2 treatment reduced HFD-induced insulin resistance by 50% during hyperinsulinemic euglycemic clamp studies and improved insulin signaling (Akt phosphorylation) in insulin-stimulated skeletal muscles. Unexpectedly, we found that E2 treatment enhanced cytokine (IL-6, TNF-α) and plasminogen activator inhibitor-1 mRNA expression induced by HFD in the liver and visceral adipose tissue. Interestingly, although the proinflammatory effect of E2 was abolished in visceral adipose tissue from chimeric mice grafted with bone marrow cells from ERα-deficient mice, the beneficial effect of the hormone on glucose tolerance was not altered, suggesting that the metabolic and inflammatory effects of estrogens can be dissociated. Eventually comparison of sham-operated with ovariectomized HFD-fed mice demonstrated that endogenous estrogens levels are sufficient to exert a full protective effect against insulin resistance and glucose intolerance. In conclusion, the regulation of the ERα pathway could represent an effective strategy to reduce the impact of high-fat diet-induced type 2 diabetes.

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Black rice anthocyanins alleviate hyperlipidemia, liver steatosis and insulin resistance by regulating lipid metabolism and gut microbiota in obese mice

Food & Function ◽

10.1039/d1fo01394g ◽

2021 ◽

Author(s):

Haizhao Song ◽

Xinchun Shen ◽

Yang Zhou ◽

Xiaodong Zheng

Keyword(s):

Insulin Resistance ◽

Lipid Metabolism ◽

Gut Microbiota ◽

Hepatic Steatosis ◽

High Fat Diet ◽

Liver Steatosis ◽

Obese Mice ◽

Black Rice ◽

High Fat ◽

Diet Induced Obesity

Supplementation of black rice anthocyanins (BRAN) alleviated high fat diet-induced obesity, insulin resistance and hepatic steatosis by improvement of lipid metabolism and modification of the gut microbiota.

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Effect of the Hepatocyte-Specific Deletion of SND1 in Mice on the Liver Insulin Resistance and Acute Liver Failure

10.21203/rs.3.rs-48660/v1 ◽

2020 ◽

Author(s):

Chunyan Zhao ◽

Xiaoteng Cui ◽

Baoxin Qian ◽

Nan Zhang ◽

Lingbiao Xin ◽

...

Keyword(s):

Insulin Resistance ◽

Liver Failure ◽

Acute Liver Failure ◽

Cholesterol Level ◽

Hepatic Steatosis ◽

Glucose Homeostasis ◽

Hepatic Failure ◽

High Fat Diet ◽

High Fat ◽

Specific Deletion

Abstract Background: The multifunctional protein SND1 was reported to be involved in a variety of biological processes, such as cell cycle, proliferation or lipogenesis. We previously proposed that global-expressed SND1 in vivo is likely to be a key regulator for ameliorating HFD-induced hepatic steatosis and systemic insulin resistance. Herein, we are very interested in investigating further whether the hepatocyte-specific deletion of SND1 affects the insulin resistance or acute liver failure (ALF) of mice.Methods: By using Cre-loxP technique, we constructed conditional knockout (LKO) mice of SND1 driven by albumin in hepatocytes and analyze the changes of glucose homeostasis, cholesterol level, hepatic steatosis and hepatic failure under the treatment of high-fat diet (HFD) or upon the simulation of Lipopolysaccharide/galactosamine (LPS/GalN).Results: No difference for the body weight, liver weight, and cholesterol level was detected. Furthermore, we did not observe the alteration of glucose homeostasis in SND1 hepatic knockout mice on either chow diet or high-fat diet. Besides, hepatocyte-specific deletion of SND1 failed to influence the hepatic failure of mice induced by LPS/GalN.Conclusions: These findings suggest that hepatic SND1, independently, is insufficient for changing glucose homeostasis, hepatic lipid accumulation and inflammation. The synergistic action of multiple organs may contribute to the role of SND1 in insulin sensitivity or inflammatory response.

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WDR76 mediates obesity and hepatic steatosis via HRas destabilization

Scientific Reports ◽

10.1038/s41598-019-56211-6 ◽

2019 ◽

Vol 9 (1) ◽

Author(s):

Jong-Chan Park ◽

Woo-Jeong Jeong ◽

Seol Hwa Seo ◽

Kang-Yell Choi

Keyword(s):

Insulin Resistance ◽

Hepatic Steatosis ◽

High Fat Diet ◽

Metabolic Regulation ◽

Adipocyte Differentiation ◽

High Fat ◽

Active Protein ◽

Wd40 Repeat ◽

Ras Protein ◽

Protein Kinase Signaling

AbstractRas/MAPK (mitogen active protein kinase) signaling plays contradictory roles in adipocyte differentiation and is tightly regulated during adipogenesis. However, mechanisms regulating adipocyte differentiation involving Ras protein stability regulation are unknown. Here, we show that WD40 repeat protein 76 (WDR76), a novel Ras regulating E3 linker protein, controls 3T3-L1 adipocyte differentiation through HRas stability regulation. The roles of WDR76 in obesity and metabolic regulation were characterized using a high-fat diet (HFD)-induced obesity model using Wdr76−/− mice and liver-specific Wdr76 transgenic mice (Wdr76Li−TG). Wdr76−/− mice are resistant to HFD-induced obesity, insulin resistance and hyperlipidemia with an increment of HRas levels. In contrast, Wdr76Li-TG mice showed increased HFD-induced obesity, insulin resistance with reduced HRas levels. Our findings suggest that WDR76 controls HFD-induced obesity and hepatic steatosis via HRas destabilization. These data provide insights into the links between WDR76, HRas, and obesity.

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Disrupting phosphatase SHP2 in macrophages protects mice from high-fat diet-induced hepatic steatosis and insulin resistance by elevating IL-18 levels

Journal of Biological Chemistry ◽

10.1074/jbc.ra119.011840 ◽

2020 ◽

Vol 295 (31) ◽

pp. 10842-10856 ◽

Cited By ~ 1

Author(s):

Wen Liu ◽

Ye Yin ◽

Meijing Wang ◽

Ting Fan ◽

Yuyu Zhu ◽

...

Keyword(s):

Insulin Resistance ◽

Type 2 Diabetes ◽

Hepatic Steatosis ◽

High Fat Diet ◽

Metabolic Disorders ◽

Metabolic Diseases ◽

Low Grade ◽

High Fat ◽

Caspase 1

Chronic low-grade inflammation plays an important role in the pathogenesis of type 2 diabetes. Src homology 2 domain-containing tyrosine phosphatase-2 (SHP2) has been reported to play diverse roles in different tissues during the development of metabolic disorders. We previously reported that SHP2 inhibition in macrophages results in increased cytokine production. Here, we investigated the association between SHP2 inhibition in macrophages and the development of metabolic diseases. Unexpectedly, we found that mice with a conditional SHP2 knockout in macrophages (cSHP2-KO) have ameliorated metabolic disorders. cSHP2-KO mice fed a high-fat diet (HFD) gained less body weight and exhibited decreased hepatic steatosis, as well as improved glucose intolerance and insulin sensitivity, compared with HFD-fed WT littermates. Further experiments revealed that SHP2 deficiency leads to hyperactivation of caspase-1 and subsequent elevation of interleukin 18 (IL-18) levels, both in vivo and in vitro. Of note, IL-18 neutralization and caspase-1 knockout reversed the amelioration of hepatic steatosis and insulin resistance observed in the cSHP2-KO mice. Administration of two specific SHP2 inhibitors, SHP099 and Phps1, improved HFD-induced hepatic steatosis and insulin resistance. Our findings provide detailed insights into the role of macrophagic SHP2 in metabolic disorders. We conclude that pharmacological inhibition of SHP2 may represent a therapeutic strategy for the management of type 2 diabetes.

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