scholarly journals Exercise Intervention Mitigates Pathological Liver Changes in NAFLD Zebrafish by Activating SIRT1/AMPK/NRF2 Signaling

2021 ◽  
Vol 22 (20) ◽  
pp. 10940
Author(s):  
Yunyi Zou ◽  
Zhanglin Chen ◽  
Chenchen Sun ◽  
Dong Yang ◽  
Zuoqiong Zhou ◽  
...  

Non-alcoholic fatty liver disease (NAFLD) is a common disease that causes serious liver damage. Exercise is recognized as a non-pharmacological tool to improve the pathology of NAFLD. However, the antioxidative effects and mechanisms by which exercise ameliorates NAFLD remain unclear. The present study conducted exercise training on zebrafish during a 12-week high-fat feeding period to study the antioxidant effect of exercise on the liver. We found that swimming exercise decreased lipid accumulation and improved pathological changes in the liver of high-fat diet-fed zebrafish. Moreover, swimming alleviated NOX4-derived reactive oxygen species (ROS) overproduction and reduced methanedicarboxylic aldehyde (MDA) levels. We also examined the anti-apoptotic effects of swimming and found that it increased the expression of antiapoptotic factor bcl2 and decreased the expression of genes associated with apoptosis (caspase3, bax). Mechanistically, swimming intervention activated SIRT1/AMPK signaling-mediated lipid metabolism and inflammation as well as enhanced AKT and NRF2 activation and upregulated downstream antioxidant genes. In summary, exercise attenuates pathological changes in the liver induced by high-fat diets. The underlying mechanisms might be related to NRF2 and mediated by SIRT1/AMPK signaling.

2021 ◽  
Author(s):  
Tengda Huang ◽  
Jingsu Yu ◽  
Zupeng Luo ◽  
Lin Yu ◽  
Siqi Liu ◽  
...  

Abstract Non-alcoholic fatty liver disease (NAFLD) is a common disease with a multitude of complications. Increasing evidence shows that the dietary supplement with betaine, a natural chemical molecule, can effectively reduce the fat accumulation in the liver. Translational regulation is considered to play a vital role in gene expression, but whether betaine functions through the regulation of gene translational level is still unclear. To this end, RNC-seq (ribosome-nascent chain complex bound mRNA sequencing) and RNA-seq co-analyses were performed to identify betaine target genes by using the liver samples from high-fat diet + betaine treated and high-fat diet treated mice. The results showed that betaine does play a lipid-lowering role by regulating the expression of gene translation levels; some NAFLD- and lipid metabolism- associated genes were differentially expressed at translational level, for example. And the mRNA translation ratio (TR) of gene significantly increased after betaine treatment. Besides, it is found that the regulation of some genes at transcriptional level is opposite to that at translational level, which indicates that transcriptional regulation and translational regulation may be independent from each other. Finally, we identified several candidate genes, especially Gpc1 , which may mediate the lipid-lowering effect of betaine in the liver. To sum up, this study depicted the molecular portrait of mice liver with or without betaine treatment from the angel of translatome and transcriptome, giving insights into the molecular mechanism of betaine-mediated lipid-lowering effect and also providing new clues for understanding and prevention of NAFLD.


2020 ◽  
Vol 124 (4) ◽  
pp. 396-406 ◽  
Author(s):  
Hongyang Yao ◽  
Chaonan Fan ◽  
Xiuqin Fan ◽  
Yuanyuan Lu ◽  
Yuanyuan Wang ◽  
...  

AbstractAberration in leptin expression is one of the most frequent features in the onset and progression of obesity, but the underlying mechanisms are still unclear and need to be clarified. This study investigated the effects of the absence of gut microbiota on body weight and the expression and promoter methylation of the leptin. Male C57 BL/6 J germ-free (GF) and conventional (CV) mice (aged 4–5 weeks) were fed either a normal-fat diet (NFD) or a high-fat diet (HFD) for 16 weeks. Six to eight mice from each group, at 15 weeks, were administered exogenous leptin for 7 d. Leptin expression and body weight gain in GF mice were increased by NFD with more CpG sites hypermethylated at the leptin promoter, whereas there was no change with HFD, compared with CV mice. Adipose or hepatic expression of genes associated with fat synthesis (Acc1, Fas and Srebp-1c), hydrolysis and oxidation (Atgl, Cpt1a, Cpt1c, Ppar-α and Pgc-1α) was lower, and hypothalamus expression of Pomc and Socs3 was higher in GF mice than levels in CV mice, particularly with NFD feeding. Exogenous leptin reduced body weight in both types of mice, with a greater effect on CV mice with NFD. Adipose Lep-R expression was up-regulated, and hepatic Fas and hypothalamic Socs3 were down-regulated in both types of mice. Expression of fat hydrolysis and oxidative genes (Atgl, Hsl, Cpt1a, Cpt1c, Ppar-α and Pgc-1α) was up-regulated in CV mice. Therefore, the effects of gut microbiota on the leptin expression and body weight were affected by dietary fat intake.


2019 ◽  
Vol 9 (1) ◽  
Author(s):  
Dandan Sheng ◽  
Shanmin Zhao ◽  
Lu Gao ◽  
Huifei Zheng ◽  
Wenting Liu ◽  
...  

Abstract Background Babaodan (BBD), a traditional Chinese medicine, has been shown to have protective effects during liver injury and ameliorate liver disease progression, but little is known about its effect on non-alcoholic fatty liver disease (NAFLD). The aim of this study was to investigate the effects of BBD on obesity-induced NAFLD. Methods C57BL/6 J mice were fed with normal diet, high fat diet (HFD) or HFD + BBD for 8 weeks. Weights of all mice were recorded every 3 days. At the end of the experiments, the level of livers, kidneys and adipose tissues of each animal was weighed. Blood serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C) cholesterol, low density lipoprotein cholesterol (LDL-C), glucose and leptin were detected with appropriate test kits. Haematoxylin–eosin (HE), Masson trichrome and Oil Red O staining of the liver were performed. We applied immunohistochemical analysis to investigate the expression of TNF-α, IL-6 and leptin in liver tissue. The expression of genes related lipid anabolism (SREBP1-c, ACC, SCD-1, LXRα and CD36) and ß-oxidation (CPT-1 and PPARα) in liver and adipose tissues was determined by RT-PCR. The expression of AMPK and p-AMPK was determined by western blot analysis. Results We found the weight of bodies and tissues (retroperitoneal fat pads, kidneys and livers) of mice fed with HFD + BBD were significantly lower than that of HFD-fed mice. And liver injury induced by HFD was relieved in mice treated with BBD, accompanied with significant reduction were observed in serum ALT/AST activities and alleviated pathological damage. The levels of glucose, TG, TC, HDL-C and LDL-C in the liver or serum were significantly decreased on HFD + BBD group compared with HFD group. Furthermore, BBD treatment reduced the level of TNF-α and IL-6 induced by HFD. The level of leptin in the liver and serum were reduced in mice fed with HFD + BBD than that of HFD-fed mice. Several lipid synthesis genes (SREBP1-c, ACC, SCD-1, LXRα and CD36) were down-regulated and that of ß-oxidation (CPT-1 and PPARα) up-regulated in HFD + BBD group compared with HFD group. In addition, BBD increased the expression of p-AMPK compared with untreated HFD group, which suggested BBD improved the activation of AMPK pathway. Conclusion In summary, our results indicate that BBD has potential applications in the prevention and treatment of NAFLD, which may be closely related to its effect on lipid metabolism via activation of AMPK signaling.


Antioxidants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1289
Author(s):  
Anna Maria Giudetti ◽  
Daniele Vergara ◽  
Serena Longo ◽  
Marzia Friuli ◽  
Barbara Eramo ◽  
...  

Long-term high-fat diet (HFD) consumption can cause weight gain and obesity, two conditions often associated with hepatic non-alcoholic fatty liver and oxidative stress. Oleoylethanolamide (OEA), a lipid compound produced by the intestine from oleic acid, has been associated with different beneficial effects in diet-induced obesity and hepatic steatosis. However, the role of OEA on hepatic oxidative stress has not been fully elucidated. In this study, we used a model of diet-induced obesity to study the possible antioxidant effect of OEA in the liver. In this model rats with free access to an HFD for 77 days developed obesity, steatosis, and hepatic oxidative stress, as compared to rats consuming a low-fat diet for the same period. Several parameters associated with oxidative stress were then measured after two weeks of OEA administration to diet-induced obese rats. We showed that OEA reduced, compared to HFD-fed rats, obesity, steatosis, and the plasma level of triacylglycerols and transaminases. Moreover, OEA decreased the amount of malondialdehyde and carbonylated proteins and restored the activity of antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase, which decreased in the liver of HFD-fed rats. OEA had also an improving effect on parameters linked to endoplasmic reticulum stress, thus demonstrating a role in the homeostatic control of protein folding. Finally, we reported that OEA differently regulated the expression of two transcription factors involved in the control of lipid metabolism and antioxidant genes, namely nuclear factor erythroid-derived 2-related factor 1 (Nrf1) and Nrf2, thus suggesting, for the first time, new targets of the protective effect of OEA in the liver.


2021 ◽  
Author(s):  
Ankita Sharma ◽  
Sumit Kr Anand ◽  
Neha Singh ◽  
Akshay Dwarkanath ◽  
Upendra Nath Dwivedi ◽  
...  

Non-alcoholic fatty liver disease (NAFLD), a chronic metabolic disorder is concomitant with oxidative stress and inflammation.


2021 ◽  
Vol 108 (Supplement_4) ◽  
Author(s):  
A Peloso ◽  
Q Gex ◽  
M Tihy ◽  
B Moeckli ◽  
F Slits ◽  
...  

Abstract Objective Non-alcoholic fatty liver disease (NAFLD) is an increasingly common disease, which can lead to hepatocellular carcinoma (HCC). It is associated with an increased portal pressure, which can alter the intestinal barrier, increase the translocation of bacterial products, and further worsen NAFLD. We hypothesized that this vicious circle can be broken by surgical porto-systemic vein shunting (PSVS), and previously demonstrated that PSVS can decrease the histological features of NAFLD in a high-fat diet (HFD) mouse model. We now test whether PSVS can also impact de-novo hepatocarcinogenesis. Methods C57BL/6 mice received HFD starting from 4 weeks of age. HCC was induced by intraperitoneal injection of DEN at 25mg/kg on week 2 and PSVS (n = 18) (or sham surgery (n = 18)) are created at 8 weeks. HCC burden was assessed by MRI and, finally, by macroscopic and histomorphology assessments. HCC features of aggressiveness, including solid growth pattern and fat component have been also evaluated. Results At 40 weeks of HFD feeding, tumors were identified in all the animals. Shunted HFD mice showed a reduced number of tumor nodules compared to sham (median nodules 8 vs 14, -42.9%; p = 0.0471) while associated to a greater average total tumor volume (709.3 vs 197 mm3, +258,6%; p = 0.0245). This correlated with an increased median tumor volume in shunted mice (16.30 vs 72.45 mm3, +344,5%; p = 0.0011). Notably, HCC histology of shunted mice was hallmarked by accentuated trend concerning HCC fatty change combined to a less pronounced solid growth pattern (p = 0.193). Conclusion PSVS leads to the presence of larger HCCs, potentially linked to the proportionally increased arterial supply of the liver. However, it demonstrates a protective effect on HCC carcinogenesis (< number of tumors). Collectively, this data suggests that portal pressure could represent a potential therapeutic target to attenuate liver steatosis and NAFLD-related HCC carcinogenesis.


Antioxidants ◽  
2020 ◽  
Vol 9 (11) ◽  
pp. 1042
Author(s):  
Saioa Gómez-Zorita ◽  
Maitane González-Arceo ◽  
Jenifer Trepiana ◽  
Leixuri Aguirre ◽  
Ana B Crujeiras ◽  
...  

Different studies have revealed that oxidative stress and inflammation are crucial in NAFLD (Non-alcoholic fatty liver disease). The aim of this study is to analyze whether pterostilbene and resveratrol are able to either avoid or delay the progression of non-alcoholic liver steatosis towards steatohepatitis. This has been performed by examining their effects on oxidative stress, inflammation, fibrosis and pre-carcinogenic stages. Rats were distributed into five experimental groups and were fed with either a standard diet or a high-fat high-fructose diet, supplemented or not with pterostilbene (15 or 30 mg/kg/d) or resveratrol (30 mg/kg/d), for 8 weeks. Liver histological analysis was carried out by haematoxylin–eosin staining. Serum and hepatic oxidative stress-related parameters were assessed using spectrophotometry, and the expression of genes related to inflammation, fibrosis and cancer by qRT-PCR. The dietary model used in this study led to the development of steatohepatitis, where rats displayed oxidative stress, inflammation and ballooning, although not fibrosis. It also modified the expression of hepatocarcinoma-related genes. The results show, for the first time, that pterostilbene was able to partially prevent these alterations, with the exception of changes in hepatocarcinoma-related genes, mainly at 30 mg/kg/d. Pterostilbene was more effective than its parent compound resveratrol, probably due to its high bioavailability and higher anti-oxidant and anti-inflammatory activities, attributable to its different chemical structure.


Nutrients ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 673 ◽  
Author(s):  
Geum-Hwa Lee ◽  
Cheng Peng ◽  
Seon-Ah Park ◽  
The-Hiep Hoang ◽  
Hwa-Young Lee ◽  
...  

Non-alcoholic fatty liver disease (NAFLD) is prevalent in the elderly population, and has symptoms ranging from liver steatosis to advanced fibrosis. Citrus peel extracts (CPEs) contain compounds that potentially improve dyslipidemia; however, the mechanism of action and effects on hepatic steatosis regulation remains unclear. Current study was aimed to investigate the protective effect of CPEs extracted through hot-air drying (CPEW) and freeze-drying (CPEF) and the underlying mechanism in a rat model of high-fat diet-induced NAFLD. The high-fat diet (HFD)-fed rats showed significant increase in total cholesterol, alanine aminotransferase (ALT), triglycerides, aspartate aminotransferase (AST), and lipid peroxidation compared to the normal chow-diet (NCD) group rats; but CPEW and CPEF limited this effect. CPEW and CPEF supplementation reduced both hepatocyte steatosis and fat accumulation involving the regulatory effect of mTORC1. Collectively, CPEW and CPEF protected deterioration of liver steatosis with AMPK activation and regulating ROS accumulation associated with interstitial disorders, which are also associated with endoplasmic reticulum (ER) redox. Thus, the application of CPEW and CPEF may lead to the development of novel therapeutic or preventive agents against NAFLD.


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