scholarly journals Increased Tumor Growth in Mice with Diet-Induced Obesity: Impact of Ovarian Hormones

Endocrinology ◽  
2006 ◽  
Vol 147 (12) ◽  
pp. 5826-5834 ◽  
Author(s):  
Shoshana Yakar ◽  
Nomeli P. Nunez ◽  
Patricia Pennisi ◽  
Pnina Brodt ◽  
Hui Sun ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Tumor Growth ◽  
Glucose Intolerance ◽  
Tumor Development ◽  
Tumor Growth Rate ◽  
Obese Mice ◽  
Female Mice ◽  
Diet Induced Obesity ◽  
Body Adiposity ◽  
Obese Female

Obesity increases the risk of many cancers in both males and females. This study describes a link between obesity, obesity-associated metabolic alterations, and the risk of developing cancer in male and female mice. The goal of this study was to evaluate the relationship between gender and obesity and to determine the role of estrogen status in obese females and its effect on tumor growth. We examined the susceptibility of C57BL/6 mice to diet-induced obesity, insulin resistance/glucose intolerance, and tumors. Mice were injected sc with one of two tumorigenic cell lines, Lewis lung carcinoma, or mouse colon 38-adenocarcinoma. Results show that tumor growth rate was increased in obese mice vs. control mice irrespective of the tumor cell type. To investigate the effect of estrogen status on tumor development in obese females, we compared metabolic parameters and tumor growth in ovariectomized (ovx) and intact obese female mice. Obese ovx female mice developed insulin resistance and glucose intolerance similar to that observed in obese males. Our results demonstrate that body adiposity increased in ovx females irrespective of the diet administered and that tumor growth correlated positively with body adiposity. Overall, these data point to more rapid tumor growth in obese mice and suggest that endogenous sex steroids, together with diet, affect adiposity, insulin sensitivity, and tumor growth in female mice.

Female 5[beta]-reductase knockout mice are protected from diet induced obesity, insulin resistance and glucose intolerance

2016 ◽  
Author(s):  
Laura Gathercole ◽  
Matthew Chapman ◽  
Dean Larner ◽  
Petra Klusonova ◽  
Trevor Penning ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Glucose Intolerance ◽  
Knockout Mice ◽  
Diet Induced Obesity

scholarly journals Investigating New Therapeutic Strategies Targeting Hyperinsulinemia's Mitogenic Effects in a Female Mouse Breast Cancer Model

Endocrinology ◽  
2013 ◽  
Vol 154 (5) ◽  
pp. 1701-1710 ◽  
Author(s):  
Ran Rostoker ◽  
Keren Bitton-Worms ◽  
Avishay Caspi ◽  
Zila Shen-Orr ◽  
Derek LeRoith
Keyword(s):  
Breast Cancer ◽  
Tumor Growth ◽  
Breast Tumor ◽  
Experimental Studies ◽  
Tumor Development ◽  
Treated Group ◽  
Tumor Growth Rate ◽  
Breast Cancer Patients ◽  
Mitogenic Effect

Abstract Epidemiological and experimental studies have identified hyperinsulinemia as an important risk factor for breast cancer induction and for the poor prognosis in breast cancer patients with obesity and type 2 diabetes. Recently it was demonstrated that both the insulin receptor (IR) and the IGF-IR mediate hyperinsulinemia's mitogenic effect in several breast cancer models. Although IGF-IR has been intensively investigated, and anti-IGF-IR therapies are now in advanced clinical trials, the role of the IR in mediating hyperinsulinemia's mitogenic effect remains to be clarified. Here we aimed to explore the potential of IR inhibition compared to dual IR/IGF-IR blockade on breast tumor growth. To initiate breast tumors, we inoculated the mammary carcinoma Mvt-1 cell line into the inguinal mammary fat pad of the hyperinsulinemic MKR female mice, and to study the role of IR, we treated the mice bearing tumors with the recently reported high-affinity IR antagonist-S961, in addition to the well-documented IGF-IR inhibitor picropodophyllin (PPP). Although reducing IR activation, with resultant severe hyperglycemia and hyperinsulinemia, S961-treated mice had significantly larger tumors compared to the vehicle-treated group. This effect maybe secondary to the severe hyperinsulinemia mediated via the IGF-1 receptor. In contrast, PPP by partially inhibiting both IR and IGF-IR activity reduced tumor growth rate with only mild metabolic consequences. We conclude that targeting (even partially) both IR and IGF-IRs impairs hyperinsulinemia's effects in breast tumor development while simultaneously sparing the metabolic abnormalities observed when targeting IR alone with virtual complete inhibition.

scholarly journals Developmental androgen excess programs sympathetic tone and adipose tissue dysfunction and predisposes to a cardiometabolic syndrome in female mice

2013 ◽  
Vol 304 (12) ◽  
pp. E1321-E1330 ◽  
Author(s):  
Kazunari Nohara ◽  
Rizwana S. Waraich ◽  
Suhuan Liu ◽  
Mathieu Ferron ◽  
Aurélie Waget ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Adipose Tissue ◽  
Glucose Intolerance ◽  
Adult Female ◽  
Sympathetic Tone ◽  
Visceral Adiposity ◽  
Androgen Excess ◽  
Altered Expression ◽  
Female Mice ◽  
The Impact

Among women, the polycystic ovarian syndrome (PCOS) is considered a form of metabolic syndrome with reproductive abnormalities. Women with PCOS show increased sympathetic tone, visceral adiposity with enlarged adipocytes, hypoadiponectinemia, insulin resistance, glucose intolerance, increased inactive osteocalcin, and hypertension. Excess fetal exposure to androgens has been hypothesized to play a role in the pathogenesis of PCOS. Previously, we showed that neonatal exposure to the androgen testosterone (NT) programs leptin resistance in adult female mice. Here, we studied the impact of NT on lean and adipose tissues, sympathetic tone in cardiometabolic tissues, and the development of metabolic dysfunction in mice. Neonatally androgenized adult female mice (NTF) displayed masculinization of lean tissues with increased cardiac and skeletal muscle as well as kidney masses. NTF mice showed increased and dysfunctional white adipose tissue with increased sympathetic tone in both visceral and subcutaneous fat as well as increased number of enlarged and insulin-resistant adipocytes that displayed altered expression of developmental genes and hypoadiponectinemia. NTF exhibited dysfunctional brown adipose tissue with increased mass and decreased energy expenditure. They also displayed decreased undercarboxylated and active osteocalcin and were predisposed to obesity during chronic androgen excess. NTF showed increased renal sympathetic tone associated with increased blood pressure, and they developed glucose intolerance and insulin resistance. Thus, developmental exposure to testosterone in female mice programs features of cardiometabolic dysfunction, as can be observed in women with PCOS, including increased sympathetic tone, visceral adiposity, insulin resistance, prediabetes, and hypertension.

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

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.

BCAA Supplementation in Mice with Diet-Induced Obesity Alters the Metabolome Without Impairing Glucose Homeostasis

Endocrinology ◽  
2021 ◽  
Author(s):  
Jennifer Lee ◽  
Archana Vijayakumar ◽  
Phillip J White ◽  
Yuping Xu ◽  
Olga Ilkayeva ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Glucose Homeostasis ◽  
Obese Mice ◽  
High Fat ◽  
Leucine Oxidation ◽  
Insulin Resistant ◽  
Diet Induced Obesity ◽  
Chain Acyl ◽  
Branched Chain ◽  
Relationship Of

Abstract Circulating branched chain amino acid (BCAA) levels are elevated in obese humans and genetically obese rodents. However, the relationship of BCAAs to insulin resistance in diet-induced obese mice, a commonly used model to study glucose homeostasis, is still ill-defined. Here we examined how high-fat high-sucrose (HFHS) or high-fat diet (HFD) feeding, with or without BCAA supplementation in water, alters the metabolome in serum/plasma and tissues in mice and whether raising circulating BCAA levels worsens insulin resistance and glucose intolerance. Neither HFHS nor HFD-feeding raised circulating BCAA levels in insulin-resistant diet-induced obese mice. BCAA supplementation raised circulating BCAA and BCKA levels and C5-OH/C3-DC acylcarnitines (AC) in muscle from HFHS or HFD-fed mice, but did not worsen insulin resistance. A set of short and long-chain acyl CoAs were elevated by diet alone in muscle, liver and WAT, but not increased further by BCAA supplementation. HFD feeding reduced valine and leucine oxidation in WAT but not in muscle. BCAA supplementation markedly increased valine oxidation in muscle from HFD-fed mice while leucine oxidation was unaffected by diet or BCAA treatment. Here we establish an extensive metabolome database showing tissue-specific changes in mice on two different HFDs, with or without BCAA supplementation. We conclude that mildly elevating circulating BCAAs and a subset of ACs by BCAA supplementation does not worsen insulin resistance or glucose tolerance in mice. This work highlights major differences in the effects of BCAAs on glucose homeostasis in diet-induced obese mice versus data reported in obese rats and in humans.

scholarly journals Obesity Augments Glucocorticoid-Dependent Muscle Atrophy in Male C57BL/6J Mice

Biomedicines ◽  
2020 ◽  
Vol 8 (10) ◽  
pp. 420
Author(s):  
Laura C. Gunder ◽  
Innocence Harvey ◽  
JeAnna R. Redd ◽  
Carol S. Davis ◽  
Ayat AL-Tamimi ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Mouse Model ◽  
Muscle Atrophy ◽  
Lean Mass ◽  
Muscle Fibers ◽  
Muscle Size ◽  
Type Ii ◽  
Obese Mice ◽  
Diet Induced Obesity ◽  
Synthetic Glucocorticoid

Glucocorticoids promote muscle atrophy by inducing a class of proteins called atrogenes, resulting in reductions in muscle size and strength. In this work, we evaluated whether a mouse model with pre-existing diet-induced obesity had altered glucocorticoid responsiveness. We observed that all animals treated with the synthetic glucocorticoid dexamethasone had reduced strength, but that obesity exacerbated this effect. These changes were concordant with more pronounced reductions in muscle size, particularly in Type II muscle fibers, and potentiated induction of atrogene expression in the obese mice relative to lean mice. Furthermore, we show that the reductions in lean mass do not fully account for the dexamethasone-induced insulin resistance observed in these mice. Together, these data suggest that obesity potentiates glucocorticoid-induced muscle atrophy.

Diet-Induced Obesity and Mammary Tumor Development in MMTV-neu Female Mice

2004 ◽  
Vol 50 (2) ◽  
pp. 174-180 ◽  
Author(s):  
Margot P. Cleary ◽  
Joseph P. Grande ◽  
Subhash C. Juneja ◽  
Nita J. Maihle
Keyword(s):  
Mammary Tumor ◽  
Tumor Development ◽  
Female Mice ◽  
Diet Induced Obesity

scholarly journals Enriched environment inhibits breast cancer progression in obese models with intact leptin signaling

2019 ◽  
Vol 26 (5) ◽  
pp. 483-495 ◽  
Author(s):  
Grant D Foglesong ◽  
Nicholas J Queen ◽  
Wei Huang ◽  
Kyle J Widstrom ◽  
Lei Cao
Keyword(s):  
Breast Cancer ◽  
Tumor Growth ◽  
Cancer Progression ◽  
Environmental Enrichment ◽  
Tumor Growth Rate ◽  
Breast Tumorigenesis ◽  
Leptin Signaling ◽  
Global Epidemic ◽  
Diet Induced Obesity ◽  
Mammary Tumor Growth

Obesity is becoming a global epidemic and is a risk factor for breast cancer. Environmental enrichment (EE), a model recapitulating an active lifestyle, leads to leanness, resistance to diet-induced obesity (DIO) and cancer. One mechanism is the activation of the hypothalamic–sympathoneural–adipocyte (HSA) axis. This results in the release of norepinephrine onto adipose tissue inducing a drop of leptin. This study aimed to test the effects of EE on breast cancer onset and progression while considering the effect of leptin by utilizing the transgenic MMTV-PyMT model as well as several models of varied leptin signaling. EE was highly effective at reducing weight gain, regardless of the presence of leptin. However, the effects of EE on tumor progression were dependent on leptin signaling. EE decreased leptin and reduced mammary tumor growth rate in MMTV-PyMT spontaneous and DIO transplantation models; in contrast, the absence of leptin in ob/ob mice resulted in increased tumor growth likely due to elevated norepinephrine levels. Our results suggest that the microenvironment is critical in breast tumorigenesis and that the drop in leptin is an important peripheral mediator of the EE anti-breast cancer effects, offsetting the potential pro-tumorigenic effects of norepinephrine responding to a complex environment.

scholarly journals Glucocorticoid-Induced Metabolic Disturbances are Exacerbated in Obesity

2017 ◽  
Author(s):  
Innocence Harvey ◽  
Erin J. Stephenson ◽  
JeAnna R. Redd ◽  
Quynh T. Tran ◽  
Irit Hochberg ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Fatty Liver ◽  
Hepatic Steatosis ◽  
Adult Male ◽  
Synergistic Effects ◽  
Lipolytic Enzyme ◽  
Metabolic Dysfunction ◽  
Obese Mice ◽  
Metabolic Disturbances ◽  
Diet Induced Obesity

AbstractObjective: To determine the effects of glucocorticoid-induced metabolic dysfunction in the presence of diet-induced obesity. Methods: C57BL/6J adult male lean and diet-induced obese mice were given dexamethasone for different durations and levels of hepatic steatosis, insulin resistance and lipolysis were determined. Results: Obese mice given dexamethasone had significant, synergistic effects on insulin resistance and markers of lipolysis, as well as hepatic steatosis. This was associated with synergistic transactivation of the lipolytic enzyme ATGL. Conclusions: The combination of chronically elevated glucocorticoids and obesity leads to exacerbations in metabolic dysfunction. Our findings suggest lipolysis may be a key player in glucocorticoid-induced insulin resistance and fatty liver in individuals with obesity.

Sign in / Sign up

Export Citation Format

Share Document