scholarly journals Adipocyte NR1D1 dictates adipose tissue expansion during obesity

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Ann Louise Hunter ◽  
Charlotte E Pelekanou ◽  
Nichola J Barron ◽  
Rebecca C Northeast ◽  
Magdalena Grudzien ◽  
...  
Keyword(s):  
Gene Expression ◽  
Insulin Resistance ◽  
Adipose Tissue ◽  
Circadian Clock ◽  
High Fat Diet ◽  
Tissue Expansion ◽  
High Fat ◽  
Clock Component ◽  
Similar Phenotype ◽  
Differential Gene

The circadian clock component NR1D1 (REVERBα) is considered a dominant regulator of lipid metabolism, with global Nr1d1 deletion driving dysregulation of white adipose tissue (WAT) lipogenesis and obesity. However, a similar phenotype is not observed under adipocyte-selective deletion (Nr1d1Flox2-6:AdipoqCre), and transcriptional pro1ling demonstrates that, under basal conditions, direct targets of NR1D1 regulation are limited, and include the circadian clock and collagen dynamics. Under high-fat diet (HFD) feeding, Nr1d1Flox2-6:AdipoqCre mice do manifest profound obesity, yet without the accompanying WAT in2ammation and 1brosis exhibited by controls. Integration of the WAT NR1D1 cistrome with differential gene expression reveals broad control of metabolic processes by NR1D1 which is unmasked in the obese state. Adipocyte NR1D1 does not drive an anticipatory daily rhythm in WAT lipogenesis, but rather modulates WAT activity in response to alterations in metabolic state. Importantly, NR1D1 action in adipocytes is critical to the development of obesity-related WAT pathology and insulin resistance.

scholarly journals Adipocyte REVERBα dictates adipose tissue expansion during obesity

2020 ◽  
Author(s):  
A. Louise Hunter ◽  
Charlotte E. Pelekanou ◽  
Nichola J. Barron ◽  
Rebecca C. Northeast ◽  
Antony Adamson ◽  
...  
Keyword(s):  
Gene Expression ◽  
Adipose Tissue ◽  
Circadian Clock ◽  
High Fat Diet ◽  
Transcriptional Profiling ◽  
Tissue Expansion ◽  
High Fat ◽  
Clock Component ◽  
Similar Phenotype ◽  
Differential Gene

ABSTRACTThe circadian clock component REVERBα is considered a dominant regulator of lipid metabolism, with global Reverbα deletion driving dysregulation of white adipose tissue (WAT) lipogenesis and obesity. However, a similar phenotype is not observed under adipocyte-selective deletion (ReverbαFlox2-6AdipoCre), and transcriptional profiling demonstrates that, under basal conditions, direct targets of REVERBα regulation are limited, and include the circadian clock and collagen dynamics. Under high-fat diet (HFD) feeding, ReverbαFlox2-6AdipoCre mice do manifest profound obesity, yet without the accompanying WAT inflammation and fibrosis exhibited by controls. Integration of the WAT REVERBα cistrome with differential gene expression reveals broad control of metabolic processes by REVERBα which is unmasked in the obese state. Adipocyte REVERBα does not drive an anticipatory daily rhythm in WAT lipogenesis, but rather modulates WAT activity in response to alterations in metabolic state. Importantly, REVERBα action in adipocytes is critical to the development of obesity-related WAT pathology and insulin resistance.

Abstract 6260: Up-Regulated Expression of MicroRNA-143 in Association with Obesity in the Adipose Tissue of Mice Fed High Fat Diet

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Rieko Takanabe ◽  
Koh Ono ◽  
Tomohide Takaya ◽  
Takahiro Horie ◽  
Hiromichi Wada ◽  
...  
Keyword(s):  
Gene Expression ◽  
Insulin Resistance ◽  
Body Weight ◽  
Adipose Tissue ◽  
High Fat Diet ◽  
Control Cell ◽  
High Fat ◽  
Expression Levels ◽  
Mesenteric Fat ◽  
Regulated Expression

Obesity is the result of an expansion and increase in the number of individual adipocytes. Since changes in gene expression during adipocyte differentiation and hypertrophy are closely associated with insulin resistance and cardiovascular diseases, further insight into the molecular basis of obesity is needed to better understand obesity-associated diseases. MicroRNAs (miRNAs) are approximately 17–24nt single stranded RNA, that post-transcriptionally regulate gene expression. MiRNAs control cell growth, differentiation and metabolism, and may be also involved in pathogenesis and pathophysiology of diseases. It has been proposed that miR-143 plays a role in the differentiation of preadipocytes into mature adipocytes in culture. However, regulated expression of miR-143 in the adult adipose tissue during the development of obesity in vivo is unknown. To solve this problem, C57BL/6 mice were fed with either high-fat diet (HFD) or normal chow (NC). Eight weeks later, severe insulin resistance was observed in mice on HFD. Body weight increased by 35% and the mesenteric fat weight increased by 3.3-fold in HFD mice compared with NC mice. We measured expression levels of miR-143 in the mesenteric fat tissue by real-time PCR and normalized with those of 5S ribosomal RNA. Expression of miR-143 in the mesenteric fat was significantly up-regulated (3.3-fold, p<0.05) in HFD mice compared to NC mice. MiR-143 expression levels were positively correlated with body weight (R=0.577, p=0.0011) and the mesenteric fat weight (R=0.608, p=0.0005). We also measured expression levels in the mesenteric fat of PPARγ and AP2, whose expression are deeply involved in the development of obesity, insulin resistant and arteriosclerosis. The expression levels of miR-143 were closely correlated with those of PPARγ (R=0.600, p=0.0040) and AP2 (R=0.630, p=0.0022). These findings provide the first evidence for up-regulated expression of miR-143 in the mesenteric fat of HFD-induced obese mice, which might contribute to regulated expression of genes involved in the pathophysiology of obesity.

scholarly journals Peripancreatic adipose tissue protects against high-fat-diet-induced hepatic steatosis and insulin resistance in mice

2020 ◽  
Vol 44 (11) ◽  
pp. 2323-2334
Author(s):  
Belén Chanclón ◽  
Yanling Wu ◽  
Milica Vujičić ◽  
Marco Bauzá-Thorbrügge ◽  
Elin Banke ◽  
...  
Keyword(s):  
Gene Expression ◽  
Insulin Resistance ◽  
Adipose Tissue ◽  
Hepatic Steatosis ◽  
High Fat Diet ◽  
Obese Mice ◽  
High Fat ◽  
Insulin Levels ◽  
Fat Depots ◽  
Fat Depot

Abstract Background/objectives Visceral adiposity is associated with increased diabetes risk, while expansion of subcutaneous adipose tissue may be protective. However, the visceral compartment contains different fat depots. Peripancreatic adipose tissue (PAT) is an understudied visceral fat depot. Here, we aimed to define PAT functionality in lean and high-fat-diet (HFD)-induced obese mice. Subjects/methods Four adipose tissue depots (inguinal, mesenteric, gonadal, and peripancreatic adipose tissue) from chow- and HFD-fed male mice were compared with respect to adipocyte size (n = 4–5/group), cellular composition (FACS analysis, n = 5–6/group), lipogenesis and lipolysis (n = 3/group), and gene expression (n = 6–10/group). Radioactive tracers were used to compare lipid and glucose metabolism between these four fat depots in vivo (n = 5–11/group). To determine the role of PAT in obesity-associated metabolic disturbances, PAT was surgically removed prior to challenging the mice with HFD. PAT-ectomized mice were compared to sham controls with respect to glucose tolerance, basal and glucose-stimulated insulin levels, hepatic and pancreatic steatosis, and gene expression (n = 8–10/group). Results We found that PAT is a tiny fat depot (~0.2% of the total fat mass) containing relatively small adipocytes and many “non-adipocytes” such as leukocytes and fibroblasts. PAT was distinguished from the other fat depots by increased glucose uptake and increased fatty acid oxidation in both lean and obese mice. Moreover, PAT was the only fat depot where the tissue weight correlated positively with liver weight in obese mice (R = 0.65; p = 0.009). Surgical removal of PAT followed by 16-week HFD feeding was associated with aggravated hepatic steatosis (p = 0.008) and higher basal (p < 0.05) and glucose-stimulated insulin levels (p < 0.01). PAT removal also led to enlarged pancreatic islets and increased pancreatic expression of markers of glucose-stimulated insulin secretion and islet development (p < 0.05). Conclusions PAT is a small metabolically highly active fat depot that plays a previously unrecognized role in the pathogenesis of hepatic steatosis and insulin resistance in advanced obesity.

scholarly journals The Effects of Poncirus fructus on Insulin Resistance and the Macrophage-Mediated Inflammatory Response in High Fat Diet-Induced Obese Mice

2019 ◽  
Vol 20 (12) ◽  
pp. 2858 ◽  
Author(s):  
Mia Kim ◽  
Mi Hyeon Seol ◽  
Byung-Cheol Lee
Keyword(s):  
Gene Expression ◽  
Insulin Resistance ◽  
Adipose Tissue ◽  
Kupffer Cells ◽  
High Fat Diet ◽  
Inflammatory Responses ◽  
Low Grade ◽  
Obese Mice ◽  
High Fat ◽  
Epididymal Fat

Obesity is a chronic low-grade inflammatory condition in which hypertrophied adipocytes and adipose tissue immune cells, mainly macrophages, contribute to increased circulating levels of proinflammatory cytokines. Obesity-associated chronic low-grade systemic inflammation is considered a focal point and a therapeutic target in insulin resistance and metabolic diseases. We evaluate the effect of Poncirus fructus (PF) on insulin resistance and its mechanism based on inflammatory responses in high-fat diet (HFD)-induced obese mice. Mice were fed an HFD to induce obesity and then administered PF. Body weight, epididymal fat and liver weight, glucose, lipid, insulin, and histologic characteristics were evaluated to determine the effect of PF on insulin resistance by analyzing the proportion of macrophages in epididymal fat and liver and measured inflammatory gene expression. PF administration significantly decreased the fasting and postprandial glucose, fasting insulin, HOMA-IR, total-cholesterol, triglycerides, and low-density lipoprotein cholesterol levels. The epididymal fat tissue and liver showed a significant decrease of fat accumulation in histological analysis. PF significantly reduced the number of adipose tissue macrophages (ATMs), F4/80+ Kupffer cells, and CD68+ Kupffer cells, increased the proportion of M2 phenotype macrophages, and decreased the gene expression of inflammatory cytokines. These results suggest that PF could be used to improve insulin resistance through modulation of macrophage-mediated inflammation and enhance glucose and lipid metabolism.

scholarly journals High-fat diet-induced adipose tissue expansion occurs prior to insulin resistance in C57BL/6J mice

2020 ◽  
Vol 6 (3) ◽  
pp. 198-207
Author(s):  
Ming-Qian He ◽  
Jing-Ya Wang ◽  
Yue Wang ◽  
Jing Sui ◽  
Meng Zhang ◽  
...  
Keyword(s):  
Insulin Resistance ◽  
Adipose Tissue ◽  
High Fat Diet ◽  
Tissue Expansion ◽  
High Fat

scholarly journals Cellular and physiological circadian mechanisms drive diurnal cell proliferation and expansion of white adipose tissue

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Aleix Ribas-Latre ◽  
Rafael Bravo Santos ◽  
Baharan Fekry ◽  
Yomna M. Tamim ◽  
Samay Shivshankar ◽  
...  
Keyword(s):  
Cell Proliferation ◽  
Adipose Tissue ◽  
Circadian Clock ◽  
White Adipose Tissue ◽  
High Fat Diet ◽  
Tissue Expansion ◽  
Regulatory Control ◽  
High Fat ◽  
Critical Determinant

AbstractHyperplastic expansion of white adipose tissue (WAT) relies in part on the proliferation of adipocyte precursor cells residing in the stromal vascular cell fraction (SVF) of WAT. This study reveals a circadian clock- and feeding-induced diurnal pattern of cell proliferation in the SVF of visceral and subcutaneous WAT in vivo, with higher proliferation of visceral adipocyte progenitor cells subsequent to feeding in lean mice. Fasting or loss of rhythmic feeding eliminates this diurnal proliferation, while high fat feeding or genetic disruption of the molecular circadian clock modifies the temporal expression of proliferation genes and impinges on diurnal SVF proliferation in eWAT. Surprisingly, high fat diet reversal, sufficient to reverse elevated SVF proliferation in eWAT, was insufficient in restoring diurnal patterns of SVF proliferation, suggesting that high fat diet induces a sustained disruption of the adipose circadian clock. In conclusion, the circadian clock and feeding simultaneously impart dynamic, regulatory control of adipocyte progenitor proliferation, which may be a critical determinant of adipose tissue expansion and health over time.

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

Endocrinology ◽  
2009 ◽  
Vol 150 (5) ◽  
pp. 2109-2117 ◽  
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.

Sign in / Sign up

Export Citation Format

Share Document