scholarly journals Thermoneutrality Inhibits Thermogenic Markers and Exacerbates Nonalcoholic Fatty Liver in Mice (P21-068-19)

2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Lei Hao ◽  
Md Shahjalal Hossain Khan ◽  
Yujiao Zu ◽  
Jie Liu ◽  
Shu Wang

Abstract Objectives Nonalcoholic fatty liver disease (NAFLD) is the most prevalent chronic liver disease, affecting more than a third of the US population and 25% of the global population. In this study, we investigated whether manipulation of brown adipose tissue (BAT) activity via housing C57BL/6 J mice under two different housing temperatures (22°C vs 27°C) influences the development of NAFLD. Methods Male C57BL/6 J mice were randomly allocated to 4 groups (8 mice/group). Briefly, mice housed at the standard temperature (ST) (22°C) or thermoneutral temperature (TT) (27°C) were fed either a control chow diet (CHD) (Picolab rodent diet 20, LabDiet) with a regular drinking water or an “fast food” diet (FFD) (Research Diets, D12079B) plus fructose 23.1 g/L and glucose 18.9 g/L added to the drinking water for 10 weeks. Results Mice under TT had significant less food intake compared to their counter partners under ST, regardless of diets. Mice exposed to TT and fed FFD had the highest body weight and plasma leptin level among all groups. For mice fed CHD, mice at TT did not present hepatic steatosis although they slightly gained more body weight compared to mice at ST. For mice fed FFD, thermoneutral housing mice had greater liver weight, liver triglyceride, and exacerbated hepatic steatosis compared to the standard housing mice. Moreover, for mice fed FFD, TT compared to ST had significantly elevated expression of fatty acid synthase, sterol regulatory element-binding transcription factor 1, fatty acid translocase, and monocyte chemoattractant protein-1 in liver. By contrast, TT did not change expression of above genes in mice fed CHD. Furthermore, thermoneutrally housed mice displayed a decrease in gene expression of thermogenic markers, such as uncoupling protein 1, elongation of very long chain fatty acids 3, and cell death-inducing DNA fragmentation factor alpha-like effector A in BAT and inguinal white adipose tissue (WAT). Conclusions Thermoneutrality inhibits expression of thermogenic markers in both BAT and WAT, which correlated to exacerbated NAFLD in mice. Our data indicate that activating BAT and/or promoting WAT browning may represent a potential strategy for the management of NAFLD. Funding Sources The College of Human Sciences of Texas Tech University; the National Center for Complementary & Integrative Health.

2022 ◽  
Vol 12 ◽  
Author(s):  
Fei Zhou ◽  
Mingning Ding ◽  
Yiqing Gu ◽  
Guifang Fan ◽  
Chuanyang Liu ◽  
...  

Nonalcoholic fatty liver disease (NAFLD), manifested as the aberrant accumulation of lipids in hepatocytes and inflammation, has become an important cause of advanced liver diseases and hepatic malignancies worldwide. However, no effective therapy has been approved yet. Aurantio-obtusin (AO) is a main bioactive compound isolated from Cassia semen that has been identified with multiple pharmacological activities, including improving adiposity and insulin resistance. However, the ameliorating effects of AO on diet-induced NAFLD and underlying mechanisms remained poorly elucidated. Our results demonstrated that AO significantly alleviated high-fat diet and glucose-fructose water (HFSW)-induced hepatic steatosis in mice and oleic acid and palmitic acid (OAPA)-induced lipid accumulation in hepatocytes. Remarkably, AO was found to distinctly promote autophagy flux and influence the degradation of lipid droplets by inducing AMPK phosphorylation. Additionally, the induction of AMPK triggered TFEB activation and promoted fatty acid oxidation (FAO) by activating PPARα and ACOX1 and decreasing the expression of genes involved in lipid biosynthesis. Meanwhile, the lipid-lowing effect of AO was significantly prevented by the pretreatment with inhibitors of autophagy, PPARα or ACOX1, respectively. Collectively, our study suggests that AO ameliorates hepatic steatosis via AMPK/autophagy- and AMPK/TFEB-mediated suppression of lipid accumulation, which opens new opportunities for pharmacological treatment of NAFLD and associated complications.


2014 ◽  
Vol 306 (4) ◽  
pp. G320-G327 ◽  
Author(s):  
Shobha H. Ganji ◽  
Gary D. Kukes ◽  
Nils Lambrecht ◽  
Moti L. Kashyap ◽  
Vaijinath S. Kamanna

Nonalcoholic fatty liver disease (NAFLD), a leading cause of liver damage, comprises a spectrum of liver abnormalities including the early fat deposition in the liver (hepatic steatosis) and advanced nonalcoholic steatohepatitis. Niacin decreases plasma triglycerides, but its effect on hepatic steatosis is elusive. To examine the effect of niacin on steatosis, rats were fed either a rodent normal chow, chow containing high fat (HF), or HF containing 0.5% or 1.0% niacin in the diet for 4 wk. For regression studies, rats were first fed the HF diet for 6 wk to induce hepatic steatosis and were then treated with niacin (0.5% in the diet) while on the HF diet for 6 wk. The findings indicated that inclusion of niacin at 0.5% and 1.0% doses in the HF diet significantly decreased liver fat content, liver weight, hepatic oxidative products, and prevented hepatic steatosis. Niacin treatment to rats with preexisting hepatic steatosis induced by the HF diet significantly regressed steatosis. Niacin had no effect on the mRNA expression of fatty acid synthesis or oxidation genes (including sterol-regulatory element-binding protein 1, acetyl-CoA carboxylase 1, fatty acid synthase, and carnitine palmitoyltransferase 1) but significantly inhibited mRNA levels, protein expression, and activity of diacylglycerol acyltrasferase 2, a key enzyme in triglyceride synthesis. These novel findings suggest that niacin effectively prevents and causes the regression of experimental hepatic steatosis. Approved niacin formulation(s) for other indications or niacin analogs may offer a very cost-effective opportunity for the clinical development of niacin for treating NAFLD and fatty liver disease.


2021 ◽  
Vol 10 (15) ◽  
pp. 3380
Author(s):  
Chi-Ren Huang ◽  
Hung-Yi Chuang ◽  
Nai-Ching Chen ◽  
Shu-Fang Chen ◽  
Chung-Yao Hsu ◽  
...  

Antiepileptic drugs that can reduce aberrant metabolism are beneficial for patients. Zonisamide (ZNS) is a chemical with antiepileptic and antioxidant activities. Here, we evaluate the efficacy of ZNS therapy on reducing obesity and decreasing risks of vascular diseases and hepatic steatosis. Clinical and metabolic indicators including body weight, body mass index (BMI), serum lipid profiles, glycated hemoglobin (HbA1c), homocysteine, and an inflammatory marker, high-sensitivity C-reactive protein (hs-CRP), were assessed at baseline and at the end of 12 and 24 weeks of treatment. Nonalcoholic fatty liver disease was evaluated using the hepatic steatosis index (HSI). A body weight reduction of ≥5% was observed in 24.6% and 32.8% of patients after 12 and 24 weeks of ZNS treatment, respectively. After adjusting for age, sex, time, and the corresponding dependent variable at baseline, the generalized estimating equation analysis revealed that the body weight, BMI, serum levels of HbA1c, triglycerides, hs-CRP, and the index for HSI were significantly declined. These results suggest that ZNS provides benefits in patients with obesity and metabolic syndrome at high vascular risk.


Endocrinology ◽  
2014 ◽  
Vol 155 (2) ◽  
pp. 417-428 ◽  
Author(s):  
L. Nikolaenko ◽  
Y. Jia ◽  
C. Wang ◽  
M. Diaz-Arjonilla ◽  
J. K. Yee ◽  
...  

Nonalcoholic fatty liver disease is common in developed countries and is associated with obesity, metabolic syndrome, and type 2 diabetes. T deficiency is a risk factor for developing these metabolic deficiencies, but its role in hepatic steatosis has not been well studied. We investigated the effects of T on the pathogenesis of hepatic steatosis in rats fed a high-fat diet (HFD). Adult male rats were randomly placed into four groups and treated for 15 weeks: intact rats on regular chow diet (RCD), intact rats on liquid HFD (I+HFD), castrated rats on HFD (C+HFD), and castrated rats with T replacement on HFD (C+HFD+T). Fat contributed 71% energy to the HFD but only 16% of energy to the RCD. Serum T level was undetectable in castrated rats, and T replacement led to 2-fold higher mean serum T levels than in intact rats. C+HFD rats gained less weight but had higher percentage body fat than C+HFD+T. Severe micro- and macrovesicular fat accumulated in hepatocytes with multiple inflammatory foci in the livers of C+HFD. I+HFD and C+HFD+T hepatocytes demonstrated only mild to moderate microvesicular steatosis. T replacement attenuated HFD-induced hepatocyte apoptosis in castrated rats. Serum glucose and insulin levels were not increased with HFD in any group. Immunoblots showed that insulin-regulated proteins were not changed in any group. This study demonstrates that T deficiency may contribute to the severity of hepatic steatosis and T may play a protective role in hepatic steatosis and nonalcoholic fatty liver disease development without insulin resistance.


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