scholarly journals CRISPR-mediated BMP9 ablation promotes liver steatosis via the down-regulation of PPARα expression

2020 ◽  
Vol 6 (48) ◽  
pp. eabc5022
Author(s):  
Z. Yang ◽  
P. Li ◽  
Q. Shang ◽  
Y. Wang ◽  
J. He ◽  
...  
Keyword(s):  
Metabolic Syndrome ◽  
Critical Role ◽  
Liver Steatosis ◽  
Acid Oxidation ◽  
Peroxisome Proliferator ◽  
Dependent Manner ◽  
Peroxisome Proliferator Activated Receptor ◽  
Nonalcoholic Fatty Liver ◽  
Triglyceride Accumulation

Obesity drives the development of nonalcoholic fatty liver disease (NAFLD) characterized by hepatic steatosis. Several bone morphogenetic proteins (BMPs) except BMP9 were reported related to metabolic syndrome. This study demonstrates that liver cytokine BMP9 is decreased in the liver and serum of NAFLD model mice and patients. BMP9 knockdown induces lipid accumulation in Hepa 1-6 cells. BMP9–knockout mice exhibit hepatosteatosis due to down-regulated peroxisome proliferator–activated receptor α (PPARα) expression and reduced fatty acid oxidation. In vitro, recombinant BMP9 treatment attenuates triglyceride accumulation by enhancing PPARα promoter activity via the activation of p-smad. PPARα-specific antagonist GW6471 abolishes the effect of BMP9 knockdown. Furthermore, adeno-associated virus–mediated BMP9 overexpression in mouse liver markedly relieves liver steatosis and obesity-related metabolic syndrome. These findings indicate that BMP9 plays a critical role in regulating hepatic lipid metabolism in a PPARα-dependent manner and may provide a previously unknown insight into NAFLD therapeutic approaches.

scholarly journals PPARβ/δ Agonist GW501516 Inhibits Tumorigenesis and Promotes Apoptosis of the Undifferentiated Nasopharyngeal Carcinoma C666-1 Cells by Regulating miR-206

2019 ◽  
Vol 27 (8) ◽  
pp. 923-933 ◽  
Author(s):  
Linglan Gu ◽  
Yi Shi ◽  
Weimin Xu ◽  
Yangyang Ji
Keyword(s):  
Nasopharyngeal Carcinoma ◽  
Critical Role ◽  
Current Data ◽  
Peroxisome Proliferator ◽  
Dependent Manner ◽  
Promoting Effect ◽  
Apoptotic Pathway ◽  
Peroxisome Proliferator Activated Receptor

In previous investigations, we reported that peroxisome proliferator-activated receptor β/δ (PPARβ/δ) activation by GW501516 inhibits proliferation and promotes apoptosis in the undifferentiated C666-1 nasopharyngeal carcinoma (NPC) cells by modulating caspase-dependent apoptotic pathway. In the present study, the mechanism by which GW501516 induces apoptosis was explored from the perspective of microRNA (miRNA) expression. Among the assayed miRNAs that were involved in regulating the expression of antiapoptotic protein Bcl-2, miR-206 was increased significantly and specifically by GW501516 in C666-1 cells at both the in vitro level and at the in vivo xenograft samples. The induction on miR-206 expression caused by GW501516 was capable of being antagonized by the PPARβ/δ antagonist GSK3787 and AMPK antagonist dorsomorphin in C666-1 cells. GW501516’s suppression on the growth and apoptosis of C666-1 cells was found to be dependent on the presence of miR-206. miR-206 overexpression resulted in suppressed proliferation and colony formation ability, and further triggered increased apoptosis in C666-1 cells in a caspase-dependent manner. The expression of cleaved caspase 3 and caspase 9, and the ratio of Bax to Bcl-2 were elevated remarkably by miR-206. Consistent with the in vitro result, miR-206 was corroborated to suppress the ectopic NPC xenograft tumorigenesis that derived from the C666-1 cells in BALB/c nu/nu mice. Taken together, the current data demonstrated that miR-206 plays a critical role in the direct apoptosis-promoting effect induced by GW501516 in C666-1 cells. Furthermore, the emphasized tumor-suppressive role of miR-206 in the C666-1 cells indicates that it has the potential to provide a new therapeutic approach for the undifferentiated NPC.

Molecular Docking Guided Screening of Phytoconstituents from Artemisia iwayomogi as Potential PPARδ Agonists

2019 ◽  
Vol 10 (04) ◽  
pp. 588-596
Author(s):  
Ajmer Singh Grewal ◽  
Neelam Sharma ◽  
Sukhbir Singh
Keyword(s):  
Metabolic Syndrome ◽  
Binding Site ◽  
In Silico ◽  
Binding Free Energy ◽  
Ethanol Extract ◽  
Acid Oxidation ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Artemisia Iwayomogi

Metabolic syndrome is a disease condition characterized by decreased insulin sensitivity, hyperlipidemia, abdominal obesity, hypertension, and myocardial diseases, primarily related to a high-fat diet and lack of physical exercise. Peroxisome proliferator-activated receptor (PPAR) δ stimulation changes the body’s energy fuel preference to fats from sugar. PPARδ is expressed universally in all tissues of the human body, particularly those involving lipid metabolism. PPARδ is an evolving pharmacological target for the pharmacotherapeutics of diseases linked to metabolic syndrome. Artemisia iwayomogi ethanol extract was reported as PPARδ agonist and reduced diet-induced overweight via stimulation of fatty acid oxidation in the skeletal muscles. The present study is designed to evaluate in silico some phytoconstituents, including 4 coumarins, 12 flavonoids, 5 phenolic compounds and 7 caffeoyl-quinic acid derivatives found in A. iwayomogi to explore their binding mode and interactions with the PPARδ protein. A total of 28 compounds evaluated in silico, 16 compounds displayed good binding free energy, and significant docking interactions with the binding site residues of PPARδ protein supporting the in vitro PPARδ agonistic activity of A. iwayomogi extract. Amongst these, scopolin, patuletin, patuletin-3-glucoside, 1,2-bis(4-hydroxy-3-methoxyphenyl)prop-1,3-diol, 3-caffeoylquinic acid, and 1,3-dicaffeoylquinic acid displayed most significant binding interactions with binding site residues of PPARδ. This information can be utilized for developing potent and non-toxic natural PPARδ agonists for the management of disorders related to metabolic syndrome.

Natural Aldose Reductase Inhibitor: A Potential Therapeutic Agent for Non-alcoholic Fatty Liver Disease

2020 ◽  
Vol 21 (6) ◽  
pp. 599-609 ◽  
Author(s):  
Longxin Qiu ◽  
Chang Guo
Keyword(s):  
Oxidative Stress ◽  
Liver Disease ◽  
Fatty Liver ◽  
Aldose Reductase ◽  
Fatty Liver Disease ◽  
Acid Oxidation ◽  
Peroxisome Proliferator ◽  
Peroxisome Proliferator Activated Receptor ◽  
Alcoholic Fatty Liver ◽  
Nonalcoholic Fatty Liver

Aldose reductase (AR) has been reported to be involved in the development of nonalcoholic fatty liver disease (NAFLD). Hepatic AR is induced under hyperglycemia condition and converts excess glucose to lipogenic fructose, which contributes in part to the accumulation of fat in the liver cells of diabetes rodents. In addition, the hyperglycemia-induced AR or nutrition-induced AR causes suppression of the transcriptional activity of peroxisome proliferator-activated receptor (PPAR) α and reduced lipolysis in the liver, which also contribute to the development of NAFLD. Moreover, AR induction in non-alcoholic steatohepatitis (NASH) may aggravate oxidative stress and the expression of inflammatory cytokines in the liver. Here, we summarize the knowledge on AR inhibitors of plant origin and review the effect of some plant-derived AR inhibitors on NAFLD/NASH in rodents. Natural AR inhibitors may improve NAFLD at least in part through attenuating oxidative stress and inflammatory cytokine expression. Some of the natural AR inhibitors have been reported to attenuate hepatic steatosis through the regulation of PPARα-mediated fatty acid oxidation. In this review, we propose that the natural AR inhibitors are potential therapeutic agents for NAFLD.

scholarly journals Adipocyte PHLPP2 inhibition prevents obesity-induced fatty liver

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
KyeongJin Kim ◽  
Jin Ku Kang ◽  
Young Hoon Jung ◽  
Sang Bae Lee ◽  
Raffaela Rametta ◽  
...  
Keyword(s):  
Fatty Liver ◽  
Whole Body ◽  
Acid Oxidation ◽  
Chow Diet ◽  
Peroxisome Proliferator ◽  
Obese Mice ◽  
Ph Domain ◽  
Peroxisome Proliferator Activated Receptor

AbstractIncreased adiposity confers risk for systemic insulin resistance and type 2 diabetes (T2D), but mechanisms underlying this pathogenic inter-organ crosstalk are incompletely understood. We find PHLPP2 (PH domain and leucine rich repeat protein phosphatase 2), recently identified as the Akt Ser473 phosphatase, to be increased in adipocytes from obese mice. To identify the functional consequence of increased adipocyte PHLPP2 in obese mice, we generated adipocyte-specific PHLPP2 knockout (A-PHLPP2) mice. A-PHLPP2 mice show normal adiposity and glucose metabolism when fed a normal chow diet, but reduced adiposity and improved whole-body glucose tolerance as compared to Cre- controls with high-fat diet (HFD) feeding. Notably, HFD-fed A-PHLPP2 mice show increased HSL phosphorylation, leading to increased lipolysis in vitro and in vivo. Mobilized adipocyte fatty acids are oxidized, leading to increased peroxisome proliferator-activated receptor alpha (PPARα)-dependent adiponectin secretion, which in turn increases hepatic fatty acid oxidation to ameliorate obesity-induced fatty liver. Consistently, adipose PHLPP2 expression is negatively correlated with serum adiponectin levels in obese humans. Overall, these data implicate an adipocyte PHLPP2-HSL-PPARα signaling axis to regulate systemic glucose and lipid homeostasis, and suggest that excess adipocyte PHLPP2 explains decreased adiponectin secretion and downstream metabolic consequence in obesity.

scholarly journals Critical Role for Hepatocyte-Specific eNOS in NAFLD and NASH

2021 ◽  
Author(s):  
Rory P. Cunningham ◽  
Mary P. Moore ◽  
Ryan J. Daskek ◽  
Grace M. Meers ◽  
Takamune Takahashi ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Fatty Acid Oxidation ◽  
Critical Role ◽  
Acid Oxidation ◽  
Mitochondrial Fatty Acid Oxidation ◽  
Nonalcoholic Fatty Liver ◽  
Mitochondrial Fatty Acid ◽  
Endothelial Nitric Oxide

Regulation of endothelial nitric oxide synthase (eNOS) in hepatocytes may be an important target in nonalcoholic fatty liver disease (NAFLD) development and progression to steatohepatitis (NASH). In this study, we show genetic deletion and viral knockdown of hepatocyte-specific eNOS exacerbated hepatic steatosis and inflammation, decreased hepatic mitochondrial fatty acid oxidation and respiration, increased mitochondrial H<sub>2</sub>O<sub>2</sub> emission, and impaired the hepatic mitophagic (BNIP3 and LC3II) response. Conversely, overexpressing eNOS in hepatocytes in vitro and in vivo increased hepatocyte mitochondrial respiration and attenuated western diet induced NASH. Moreover, patients with elevated NAFLD activity score (histology score of worsening steatosis, hepatocyte ballooning, and inflammation) exhibited reduced hepatic eNOS expression which correlated with reduced hepatic mitochondrial fatty acid oxidation and lower hepatic protein expression of mitophagy protein BNIP3. The current study reveals an important molecular role for hepatocyte-specific eNOS as a key regulator of NAFLD/NASH susceptibility and mitochondrial quality control with direct clinical correlation to patients with NASH.

scholarly journals Dietary β-Cryptoxanthin Inhibits High-Refined Carbohydrate Diet–Induced Fatty Liver via Differential Protective Mechanisms Depending on Carotenoid Cleavage Enzymes in Male Mice

2019 ◽  
Vol 149 (9) ◽  
pp. 1553-1564 ◽  
Author(s):  
Ji Ye Lim ◽  
Chun Liu ◽  
Kang-Quan Hu ◽  
Donald E Smith ◽  
Dayong Wu ◽  
...  
Keyword(s):  
Fatty Liver ◽  
Farnesoid X Receptor ◽  
Receptor Protein ◽  
Acid Oxidation ◽  
Peroxisome Proliferator ◽  
Double Knockout ◽  
Carbohydrate Diet ◽  
Peroxisome Proliferator Activated Receptor ◽  
Nonalcoholic Fatty Liver ◽  
Β Carotene

ABSTRACT Background β-Cryptoxanthin (BCX), a provitamin A carotenoid shown to protect against nonalcoholic fatty liver disease (NAFLD), can be cleaved by β-carotene-15,15′-oxygenase (BCO1) to generate vitamin A, and by β-carotene-9′,10′-oxygenase (BCO2) to produce bioactive apo-carotenoids. BCO1/BCO2 polymorphisms have been associated with variations in plasma carotenoid amounts in both humans and animals. Objectives We investigated whether BCX feeding inhibits high refined-carbohydrate diet (HRCD)-induced NAFLD, dependent or independent of BCO1/BCO2. Methods Six-week-old male wild-type (WT) and BCO1−/−/BCO2−/− double knockout (DKO) mice were randomly fed HRCD (66.5% of energy from carbohydrate) with or without BCX (10 mg/kg diet) for 24 wk. Pathological and biochemical variables were analyzed in the liver and mesenteric adipose tissues (MATs). Data were analyzed by 2-factor ANOVA. Results Compared to their respective HRCD controls, BCX reduced hepatic steatosis severity by 33‒43% and hepatic total cholesterol by 43‒70% in both WT and DKO mice (P &lt; 0.01). Hepatic concentrations of BCX, but not retinol and retinyl palmitate, were 33-fold higher in DKO mice than in WT mice (P &lt; 0.001). BCX feeding increased the hepatic fatty acid oxidation protein peroxisome proliferator-activated receptor-α, and the cholesterol efflux gene ATP-binding cassette transporter5, and suppressed the lipogenesis gene acetyl-CoA carboxylase 1 (Acc1) in the MAT of WT mice but not DKO mice (P &lt; 0.05). BCX feeding decreased the hepatic lipogenesis proteins ACC and stearoyl-CoA desaturase-1 (3-fold and 5-fold) and the cholesterol synthesis genes 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase and HMG-CoA synthase 1 (2.7-fold and 1.8-fold) and increased the cholesterol catabolism gene cholesterol 7α-hydroxylase (1.9-fold) in the DKO but not WT mice (P &lt; 0.05). BCX feeding increased hepatic protein sirtuin1 (2.5-fold) and AMP-activated protein kinase (9-fold) and decreased hepatic farnesoid X receptor protein (80%) and the inflammatory cytokine gene Il6 (6-fold) in the MAT of DKO mice but not WT mice (P &lt; 0.05). Conclusion BCX feeding mitigates HRCD-induced NAFLD in both WT and DKO mice through different mechanisms in the liver-MAT axis, depending on the presence or absence of BCO1/BCO2.

scholarly journals Muscle PGC-1α is required for long-term systemic and local adaptations to a ketogenic diet in mice

2017 ◽  
Vol 312 (5) ◽  
pp. E437-E446 ◽  
Author(s):  
Svenia Schnyder ◽  
Kristoffer Svensson ◽  
Bettina Cardel ◽  
Christoph Handschin
Keyword(s):  
Skeletal Muscle ◽  
Weight Control ◽  
Physiological Adaptation ◽  
Acid Oxidation ◽  
Peroxisome Proliferator ◽  
Dependent Manner ◽  
Dietary Interventions ◽  
Peroxisome Proliferator Activated Receptor ◽  
Local Adaptations

Low-carbohydrate/high-fat (LCHF) diets are increasingly popular dietary interventions for body weight control and as treatment for different pathological conditions. However, the mechanisms of action are still poorly understood, in particular, in long-term administration. Besides liver, brain, and heart, skeletal muscle is one of the major organs involved in the regulation of physiological and pathophysiological ketosis. We assessed the role of the peroxisome proliferator-activated receptor γ coactivator 1α (PGC-1α) in skeletal muscle of male wild-type control and PGC-1α muscle-specific knockout mice upon 12 wk of LCHF diet feeding. Interestingly, LCHF diet administration increased oxygen consumption in a muscle PGC-1α-dependent manner, concomitant with a blunted transcriptional induction of genes involved in fatty acid oxidation and impairment in exercise performance. These data reveal a new role for muscle PGC-1α in regulating the physiological adaptation to long-term LCHF diet administration.

scholarly journals A Combination of Leucine, Metformin, and Sildenafil Treats Nonalcoholic Fatty Liver Disease and Steatohepatitis in Mice

2016 ◽  
Vol 2016 ◽  
pp. 1-16 ◽  
Author(s):  
Antje Bruckbauer ◽  
Jheelam Banerjee ◽  
Lizhi Fu ◽  
Fenfen Li ◽  
Qiang Cao ◽  
...  
Keyword(s):  
Therapeutic Efficacy ◽  
Inflammatory Marker ◽  
Atherogenic Diet ◽  
Acid Oxidation ◽  
Nonalcoholic Fatty Liver ◽  
Lipogenic Gene Expression ◽  
Hepatic Energy Metabolism ◽  
Triglyceride Accumulation ◽  
Hepatic Fatty Acid Oxidation

Sirt1, AMPK, and eNOS modulate hepatic energy metabolism and inflammation and are key players in the development of NASH. L-leucine, an allosteric Sirt1 activator, synergizes with low doses of metformin or sildenafil on the AMPK-eNOS-Sirt1 pathway to reverse mild NAFLD in preclinical mouse models. Here we tested a possible multicomponent synergy to yield greater therapeutic efficacy in NAFLD/NASH. Liver cells and macrophages or an atherogenic diet induced NASH mouse model was treated with two-way and three-way combinations. The three-way combination Sild-Met-Leu increased hepatic fatty acid oxidation and reduced lipogenic gene expression and inflammatory marker in vitro. In mice, Sild-Met-Leu reduced the diet induced increases of ALT, TGFβ, PAI-1, IL1β, and TNFα, hepatic collagen expression, and nearly completely reversed hepatocyte ballooning and triglyceride accumulation, while all two-way combinations had only modest effects. Therefore, these data provide preclinical evidence for therapeutic efficacy of Sild-Met-Leu in the treatment of NAFLD and NASH.

scholarly journals Effects of Dietary Anaplerotic and Ketogenic Energy Sources on Renal Fatty Acid Oxidation Induced by Clofibrate in Suckling Neonatal Pigs

2020 ◽  
Vol 21 (3) ◽  
pp. 726
Author(s):  
Xi Lin ◽  
Brandon Pike ◽  
Jinan Zhao ◽  
Yu Fan ◽  
Yongwen Zhu ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Palmitic Acid ◽  
Fatty Acid Oxidation ◽  
Energy Sources ◽  
Acid Oxidation ◽  
Peroxisome Proliferator ◽  
Fresh Tissue ◽  
Peroxisome Proliferator Activated Receptor ◽  
Tissue Homogenates

Maintaining an active fatty acid metabolism is important for renal growth, development, and health. We evaluated the effects of anaplerotic and ketogenic energy sources on fatty acid oxidation during stimulation with clofibrate, a pharmacologic peroxisome proliferator-activated receptor α (PPARα) agonist. Suckling newborn pigs (n = 72) were assigned into 8 dietary treatments following a 2 × 4 factorial design: ± clofibrate (0.35%) and diets containing 5% of either (1) glycerol-succinate (GlySuc), (2) tri-valerate (TriC5), (3) tri-hexanoate (TriC6), or (4) tri-2-methylpentanoate (Tri2MPA). Pigs were housed individually and fed the iso-caloric milk replacer diets for 5 d. Renal fatty acid oxidation was measured in vitro in fresh tissue homogenates using [1-14C]-labeled palmitic acid. The oxidation was 30% greater in pig received clofibrate and 25% greater (p < 0.05) in pigs fed the TriC6 diet compared to those fed diets with GlySuc, TriC5, and Tri2MPA. Addition of carnitine also stimulated the oxidation by twofold (p < 0.05). The effects of TriC6 and carnitine on palmitic acid oxidation were not altered by clofibrate stimulation. However, renal fatty acid composition was altered by clofibrate and Tri2MPA. In conclusion, modification of anaplerosis or ketogenesis via dietary substrates had no influence on in vitro renal palmitic acid oxidation induced by PPARα activation.

scholarly journals PRIC295, a Nuclear Receptor Coactivator, Identified from PPAR-Interacting Cofactor Complex

PPAR Research ◽  
2010 ◽  
Vol 2010 ◽  
pp. 1-16 ◽  
Author(s):  
Sean R. Pyper ◽  
Navin Viswakarma ◽  
Yuzhi Jia ◽  
Yi-Jun Zhu ◽  
Joseph D. Fondell ◽  
...  
Keyword(s):  
Nuclear Receptor ◽  
Target Genes ◽  
Peroxisome Proliferator ◽  
Dependent Manner ◽  
Peroxisome Proliferator Activated Receptor ◽  
Nuclear Receptor Coactivator ◽  
Evolutionarily Conserved

The peroxisome proliferator-activated receptor- (PPAR) plays a key role in lipid metabolism and energy combustion. Chronic activation of PPAR in rodents leads to the development of hepatocellular carcinomas. The ability of PPAR to induce expression of its target genes depends on Mediator, an evolutionarily conserved complex of cofactors and, in particular, the subunit 1 (Med1) of this complex. Here, we report the identification and characterization of PPAR-interacting cofactor (PRIC)-295 (PRIC295), a novel coactivator protein, and show that it interacts with the Med1 and Med24 subunits of the Mediator complex. PRIC295 contains 10 LXXLL signature motifs that facilitate nuclear receptor binding and interacts with PPAR and five other members of the nuclear receptor superfamily in a ligand-dependent manner. PRIC295 enhances the transactivation function of PPAR, PPAR, and ER. These data demonstrate that PRIC295 interacts with nuclear receptors such as PPAR and functions as a transcription coactivator underin vitroconditions and may play an important role in mediating the effectsin vivoas a member of the PRIC complex with Med1 and Med24.

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