الملخص
Objective To investigate the effects of long noncoding RNA H19 on lipid accumulation of macrophages under high fat stress and its mechanism. Methods Human THP-1 cells-derived macrophages were incubated with ox-LDL, and the effects of H19 siRNA intervention on lipid accumulation was observed. The THP-1 cells were divided into control group (conventional culture), ox-LDL group, siRNA negative control (NC siRNA) combined with ox-LDL treatment group, and H19 siRNA combined with ox-LDL treatment group. Oil red O staining was used to determine the lipid accumulation in cells, and cholesterol concentration was analyzed by enzymatic method; ATP assay kit for detecting celluar ATP content; colorimetry was used to detect the levels of oxidative stress indicators and ELISA was used to detect the levels of monocyte chemoattractant protein-1 (MCP-1) in the cell supernatant. Western blot analysis was used to detect the protein expression of ATP binding cassette transporter A1 (ABCA1), peroxisome proliferator-activated receptor α (PPARα), peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) and nuclear factor κB p-p65 (NF-κB p-p65). Results Knockdown H19 significantly inhibited intracellular lipid accumulation, decreased total cholesterol (TC) and cholesterol ester (CE) content, and decreased CE/TC ratio. Knockdown H19 significantly alleviated cell damage including an increase in ATP content, a decrease in oxidative stress levels and a decrease in MCP-1 levels, which caused by high-fat stress. H19 siRNA upregulated expression of ABCA1, PPARα and PGC-1α in THP-1 derived macrophages, downregulated NF-κB signal pathway. Conclusion Knockdown H19 upregulates PGC-1α expression in THP-1 cells and downregulates NF-κB pathway, which promotes cholesterol reverse transport, reduces inflammatory reaction and inhibits lipid accumulation.
الموضوعات
Humans , Adenosine Triphosphate , Cholesterol , NF-kappa B , PPAR alpha , RNA, Long Noncoding/genetics , RNA, Small Interfering/genetics , THP-1 Cells , Macrophages/metabolism , Lipid Metabolismالملخص
This study investigated the mechanism of Zexie Decoction(ZXD) in promoting white adipose tissue browning/brown adipose tissue activation based on the GLP-1R/cAMP/PKA/CREB pathway. A hyperlipidemia model was induced by a western diet(WD) in mice, and the mice were divided into a control group, a model group(WD), and low-, medium-, and high-dose ZXD groups. An adipogenesis model was induced in 3T3-L1 cells in vitro, and with forskolin(FSK) used as a positive control, low-, medium-, and high-dose ZXD groups were set up. Immunohistochemistry and immunofluorescence results showed that compared with the WD group, ZXD promoted the expression of UCP1 in white and brown adipose tissues, and also upregulated UCP1, CPT1β, PPARα, and other genes in the cells. Western blot analysis showed a dose-dependent increase in the protein expression of PGC-1α, UCP1, and PPARα with ZXD treatment, indicating that ZXD could promote the white adipose tissue browning/brown adipose tissue activation. Hematoxylin-eosin(HE) staining results showed that after ZXD treatment, white and brown adipocytes were significantly reduced in size, and the mRNA expression of ATGL, HSL, MGL, and PLIN1 was significantly upregulated as compared with the results in the WD group. Oil red O staining and biochemical assays indicated that ZXD improved lipid accumulation and promoted lipolysis. Immunohistochemistry and immunofluorescence staining for p-CREB revealed that ZXD reversed the decreased expression of p-CREB caused by WD. In vitro intervention with ZXD increased the protein expression of CREB, p-CREB, and p-PKA substrate, and increased the mRNA level of CREB. ELISA detected an increase in intracellular cAMP concentration with ZXD treatment. Molecular docking analysis showed that multiple active components in Alismatis Rhizoma and Atractylodis Macrocephalae Rhizoma could form stable hydrogen bond interactions with GLP-1R. In conclusion, ZXD promotes white adipose tissue browning/brown adipose tissue activation both in vivo and in vitro, and its mechanism of action may be related to the GLP-1R/cAMP/PKA/CREB pathway.
الموضوعات
Mice , Animals , Adipose Tissue, Brown , Molecular Docking Simulation , PPAR alpha/metabolism , Adipose Tissue, White , RNA, Messenger/metabolismالملخص
The study aimed to investigate the effect of anemoside B4(B4) on fatty acid metabolism in mice with colitis-associated cancer(CAC). The CAC model was established by azoxymethane(AOM)/dextran sodium sulfate(DSS) in mice. Mice were randomly divided into a normal group, a model group, and low-, medium-, and high-dose anemoside B4 groups. After the experiment, the length of the mouse colon and the size of the tumor were measured, and the pathological alterations in the mouse colon were observed using hematoxylin-eosin(HE) staining. The slices of the colon tumor were obtained for spatial metabolome analysis to analyze the distribution of fatty acid metabolism-related substances in the tumor. The mRNA levels of SREBP-1, FAS, ACCα, SCD-1, PPARα, ACOX, UCP-2, and CPT-1 were determined by real-time quantitative PCR(RT-qPCR). The results revealed that the model group showed decreased body weight(P<0.05) and colon length(P<0.001), increased number of tumors, and increased pathological score(P<0.01). Spatial metabolome analysis revealed that the content of fatty acids and their derivatives, carnitine, and phospholipid in the colon tumor was increased. RT-qPCR results indicated that fatty acid de novo synthesis and β-oxidation-related genes, such as SREBP-1, FASN, ACCα, SCD-1, ACOX, UCP-2, and CPT-1 mRNA expression levels increased considerably(P<0.05, P<0.001). After anemoside B4 administration, the colon length increased(P<0.01), and the number of tumors decreased in the high-dose anemoside B4 group(P<0.05). Additionally, spatial metabolome analysis showed that anemoside B4 could decrease the content of fatty acids and their derivatives, carnitine, and phospholipids in colon tumors. Meanwhile, anemoside B4 could also down-regulate the expression of FASN, ACCα, SCD-1, PPARα, ACOX, UCP-2, and CPT-1 in the colon(P<0.05, P<0.01, P<0.001). The findings of this study show that anemoside B4 may inhibit CAC via regulating fatty acid metabolism reprogramming.
الموضوعات
Mice , Animals , Sterol Regulatory Element Binding Protein 1 , Colitis-Associated Neoplasms , PPAR alpha/genetics , Colonic Neoplasms/genetics , Colon , Azoxymethane , RNA, Messenger , Dextran Sulfate , Colitis/drug therapy , Mice, Inbred C57BL , Disease Models, Animalالملخص
The aim of the present study was to investigate the effects of short-term ketogenic diet on the low temperature tolerance of mice and the involvement of peroxisome proliferator-activated receptor α (PPARα). C57BL/6J mice were divided into two groups: normal diet (WT+ND) group and ketogenic diet (WT+KD) group. After being fed with normal or ketogenic diet at room temperature for 2 d, the mice were exposed to 4 °C low temperature for 12 h. The changes in core temperature, blood glucose, blood pressure of mice under low temperature condition were detected, and the protein expression levels of PPARα and mitochondrial uncoupling protein 1 (UCP1) were detected by Western blot. PPARα knockout mice were divided into normal diet (PPARα-/-+ND) group and ketogenic diet (PPARα-/-+KD) group. After being fed with the normal or ketogenic diet at room temperature for 2 d, the mice were exposed to 4 °C low temperature for 12 h. The above indicators were also detected. The results showed that, at room temperature, the protein expression levels of PPARα and UCP1 in liver and brown adipose tissue of WT+KD group were significantly up-regulated, compared with those of WT+ND group. Under low temperature condition, compared with WT+ND, the core temperature and blood glucose of WT+KD group were increased, while mean arterial pressure was decreased; The ketogenic diet up-regulated PPARα protein expression in brown adipose tissue, as well as UCP1 protein expression in liver and brown adipose tissue of WT+KD group. Under low temperature condition, compared to WT+ND group, PPARα-/-+ND group exhibited decreased core temperature and down-regulated PPARα and UCP1 protein expression levels in liver, skeletal muscle, white and brown adipose tissue. Compared to the PPARα-/-+ND group, the PPARα-/-+KD group exhibited decreased core temperature and did not show any difference in the protein expression of UCP1 in liver, skeletal muscle, white and brown adipose tissue. These results suggest that the ketogenic diet promotes UCP1 expression by up-regulating PPARα, thus improving low temperature tolerance of mice. Therefore, short-term ketogenic diet can be used as a potential intervention to improve the low temperature tolerance.
الموضوعات
Animals , Mice , Adipose Tissue, Brown/metabolism , PPAR alpha/pharmacology , Diet, Ketogenic , Uncoupling Protein 1/metabolism , Blood Glucose/metabolism , Temperature , Mice, Inbred C57BL , Liver , Adipose Tissue/metabolismالملخص
OBJECTIVE@#To explore the molecular pathological mechanism of liver metabolic disorder in severe spinal muscular atrophy (SMA).@*METHODS@#The transgenic mice with type Ⅰ SMA (Smn-/- SMN20tg/2tg) and littermate control mice (Smn+/- SMN20tg/2tg) were observed for milk suckling behavior and body weight changes after birth. The mice with type Ⅰ SMA mice were given an intraperitoneal injection of 20% glucose solution or saline (15 μL/12 h), and their survival time was recorded. GO enrichment analysis was performed using the RNA-Seq data of the liver of type Ⅰ SMA and littermate control mice, and the results were verified using quantitative real-time PCR. Bisulfite sequencing was performed to examine CpG island methylation level in Fasn gene promoter region in the liver of the neonatal mice.@*RESULTS@#The neonatal mice with type Ⅰ SMA showed normal milk suckling behavior but had lower body weight than the littermate control mice on the second day after birth. Intraperitoneal injection of glucose solution every 12 h significantly improved the median survival time of type Ⅰ SMA mice from 9±1.3 to 11± 1.5 days (P < 0.05). Analysis of the RNA-Seq data of the liver showed that the expression of the target genes of PPARα related to lipid metabolism and mitochondrial β oxidation were down-regulated in the liver of type Ⅰ SMA mice. Type Ⅰ SMA mice had higher methylation level of the Fasn promoter region in the liver than the littermate control mice (76.44% vs 58.67%). In primary cultures of hepatocytes from type Ⅰ SMA mice, treatment with 5-AzaC significantly up-regulated the expressions of the genes related to lipid metabolism by over 1 fold (P < 0.01).@*CONCLUSION@#Type Ⅰ SMA mice have liver metabolic disorder, and the down-regulation of the target genes of PPARα related to lipid and glucose metabolism due to persistent DNA methylation contributes to the progression of SMA.
الموضوعات
Mice , Animals , PPAR alpha , Liver Diseases , Muscular Atrophy, Spinal/genetics , Mice, Transgenic , Body Weight , Glucoseالملخص
Objective To explore the potential targets of triclosan in the treatment of nonalcoholic fatty liver disease(NAFLD) and to provide new clues for the future research on the application of triclosan. Methods The targets of triclosan and NAFLD were obtained via network pharmacology.The protein-protein interaction network was constructed with the common targets shared by triclosan and NAFLD.The affinity of triclosan to targets was verified through molecular docking.Gene ontology(GO) annotation and Kyoto Encyclopedia of Genes and Genomes(KEGG) pathway enrichment were carried out to analyze the key targets and the potential mechanism of action.NAFLD model was established by feeding male C57BL/6J mice with high-fat diet for 12 weeks.The mice were randomly assigned into a model group and a triclosan group [400 mg/(kg·d),gavage once a day for 8 weeks].The hematoxylin-eosin(HE) staining was used for observation of the pathological changes and oil red O staining for observation of fat deposition in mouse liver.Western blotting was employed to detect the protein level of peroxisome proliferator-activated receptor alpha(PPARα) in the liver tissue. Results Triclosan and NAFLD had 34 common targets,19 of which may be the potential targets for the treatment,including albumin(ALB),PPARα,mitogen-activated protein kinase 8(MAPK8),and fatty acid synthase.Molecular docking predicted that ALB,PPARα,and MAPK8 had good binding ability to triclosan.KEGG pathway enrichment showcased that the targets were mainly enriched in peroxisome proliferator-activated receptor signaling pathway,in which ALB and MAPK8 were not involved.Triclosan alleviated the balloon-like change and lipid droplet vacuole,decreased the lipid droplet area,and up-regulated the expression level of PPARα in mouse liver tissue. Conclusion PPARα is a key target of triclosan in the treatment of NAFLD,which may be involved in fatty acid oxidation through the peroxisome proliferator activated receptor signaling pathway.
الموضوعات
Animals , Male , Mice , Liver/pathology , Mice, Inbred C57BL , Molecular Docking Simulation , Network Pharmacology , Non-alcoholic Fatty Liver Disease/drug therapy , PPAR alpha/therapeutic use , Triclosan/therapeutic useالملخص
BACKGROUND: Peroxisome proliferator-activated receptor alpha (PPARα) is associated with diabetic retinopathy (DR), and the underlying mechanism is still unclear. Aim of this work was to investigate the mechanism of PPARα in DR. METHODS: Human retinal capillary pericytes (HRCPs) were treated with high glucose (HG) to induce DR cell model. DR mouse model was established by streptozotocin injection, and then received 5-Aza-2-deoxycytidine (DAC; DNA methyltransferase inhibitor) treatment. Hematoxylin-eosin staining was performed to assess retinal tissue damage. PPARα methylation was examined by Methylation-Specific PCR. Flow cytometry and DCFH-DA fluorescent probe was used to estimate apoptosis and reactive oxygen species (ROS). The interaction between DNA methyltransferase-1 (DNMT1) and PPARα promoter was examined by Chromatin Immunoprecipitation. Quantitative real-time PCR and western blot were performed to assess gene and protein expression. RESULTS: HG treatment enhanced the methylation levels of PPARα, and repressed PPARα expression in HRCPs. The levels of apoptotic cells and ROS were significantly increased in HRCPs in the presence of HG. Moreover, DNMT1 was highly expressed in HG-treated HRCPs, and DNMT1 interacted with PPARα promoter. PPARα overexpression suppressed apoptosis and ROS levels of HRCPs, which was rescued by DNMT1 up-regulation. In DR mice, DAC treatment inhibited PPARα methylation and reduced damage of retinal tissues. CONCLUSION: DNMT1-mediated PPARα methylation promotes apoptosis and ROS levels of HRCPs and aggravates damage of retinal tissues in DR mice. Thus, this study may highlight novel insights into DR pathogenesis.
الموضوعات
Humans , Animals , Mice , Retina/pathology , PPAR alpha/genetics , Diabetic Retinopathy , DNA (Cytosine-5-)-Methyltransferase 1/metabolism , Retina/cytology , Cells, Cultured , Promoter Regions, Genetic , Apoptosis , DNA Methylation , Diabetes Mellitus , Disease Models, Animal , Methylationالملخص
The plasticizer di(2-ethylhexyl) phthalate (DEHP) has been widely used in the manufacture of polyvinyl chloride-containing products such as medical and consumer goods. Humans can easily be exposed to it because DEHP is ubiquitous in the environment. Recent research on the adverse effects of DEHP has focused on reproductive and developmental toxicity in rodents and/or humans. DEHP is a representative of the peroxisome proliferators. Therefore, peroxisome proliferator-activated receptor alpha (PPARα)-dependent pathways are the expected mode of action of several kinds of DEHP-induced toxicities. In this review, we summarize DEHP kinetics and its mechanisms of carcinogenicity and reproductive and developmental toxicity in relation to PPARα. Additionally, we give an overview of the impacts of science policy on exposure sources.
الموضوعات
Animals , Humans , Mice , Rats , Diethylhexyl Phthalate , Toxicity , Environmental Pollutants , Toxicity , Haplorhini , PPAR alpha , Genetics , Metabolism , Plasticizers , Toxicityالملخص
BACKGROUND/OBJECTIVES: Docosahexaenoic acid (DHA), an n-3 long chain polyunsaturated fatty acid (LCPUFA), is acquired by dietary intake or the in vivo conversion of α-linolenic acid. Many enzymes participating in LCPUFA synthesis are regulated by peroxisome proliferator-activated receptor alpha (PPARα). Therefore, it was hypothesized that the tissue accretion of endogenously synthesized DHA could be modified by PPARα. MATERIALS/METHODS: The tissue DHA concentrations and mRNA levels of genes participating in DHA biosynthesis were compared among PPARα homozygous (KO), heterozygous (HZ), and wild type (WT) mice (Exp I), and between WT mice treated with clofibrate (PPARα agonist) or those not treated (Exp II). In ExpII, the expression levels of the proteins associated with DHA function in the brain cortex and retina were also measured. An n3-PUFA depleted/replenished regimen was applied to mitigate the confounding effects of maternal DHA. RESULTS: PPARα ablation reduced the hepatic Acox, Fads1, and Fads2 mRNA levels, as well as the DHA concentration in the liver, but not in the brain cortex. In contrast, PPARα activation increased hepatic Acox, Fads1, Fads2 and Elovl5 mRNA levels, but reduced the DHA concentrations in the liver, retina, and phospholipid of brain cortex, and decreased mRNA and protein levels of the brain-derived neurotrophic factor in brain cortex. CONCLUSIONS: LCPUFA enzyme expression was altered by PPARα. Either PPARα deficiency or activation-decreased tissue DHA concentration is a stimulus for further studies to determine the functional significance.
الموضوعات
Animals , Mice , Brain , Brain-Derived Neurotrophic Factor , Clofibrate , Docosahexaenoic Acids , Fatty Acid Desaturases , Liver , Peroxisomes , PPAR alpha , Retina , RNA, Messengerالملخص
Tanshinone Ⅱ_A( Tan Ⅱ_A),the liposoluble constituents of Salvia miltiorrhiza,can not only ameliorate the lipidic metabolism and decrease the concentration of lipid peroxidation,but also resist oxidation damage,scavenge free radicals and control inflammation,with a protective effect on prognosis after liver function impairment. Therefore,the studies on the exact mechanism of Tan Ⅱ_A in protecting the liver can provide important theoretical and experimental basis for the prevention and treatment effect of Tan Ⅱ_A for liver injury. In the present study,the protective effects and mechanism of Tan Ⅱ_A on 4-hydroxynonenal( 4-HNE)-induced liver injury were investigated in vitro. Normal liver tissues NCTC 1469 cells were used to induce hepatocytes oxidative damages by 4-HNE treatment. The protective effect of Tan Ⅱ_A on hepatocytes oxidative damages was detected by release amount of lactate dehydrogenase( LDH) analysis and hoechst staining. The protein expression changes of peroxisome proliferator-activated receptor α( PPARα) and peroxisome proliferator response element( PPRE) were analyzed by Western blot analysis in NCTC 1469 cells before and after Tan Ⅱ_A treatment. The gene expression changes of fatty aldehyde dehydrogenase( FALDH) were analyzed by Real-time polymerase chain reaction( PCR) analysis. The results showed that 4-HNE increased the release amount of LDH,lowered the cell viability of NCTC 1469 cells,and Tan Ⅱ_A reversed 4-HNE-induced hepatocyte damage. Western blot analysis and RT-PCR analysis results showed that 4-HNE decreased the expression of PPARα and FALDH and increased the expression of 4-HNE. However,the expression of PPARα and FALDH were increased significantly and the expression of 4-HNE was decreased obviously after Tan Ⅱ_A treatment. This study confirmed that the curative effect of Tan Ⅱ_A was obvious on hepatocytes damage,and the mechanism may be associated with activating PPARα and FALDH expression as well as scavenging 4-HNE.
الموضوعات
Animals , Mice , Aldehyde Oxidoreductases , Metabolism , Aldehydes , Cell Line , Abietanes , Pharmacology , Hepatocytes , Lipid Peroxidation , Oxidative Stress , PPAR alpha , Metabolismالملخص
Although elevated serum low-density lipoprotein-cholesterol (LDL-C) is without any doubts accepted as an important risk factor for cardiovascular disease (CVD), the role of elevated triglycerides (TGs)-rich lipoproteins as an independent risk factor has until recently been quite controversial. Recent data strongly suggest that elevated TG-rich lipoproteins are an independent risk factor for CVD and that therapeutic targeting of them could possibly provide further benefit in reducing CVD morbidity, events and mortality, apart from LDL-C lowering. Today elevated TGs are treated with lifestyle interventions, and with fibrates which could be combined with omega-3 fatty acids. There are also some new drugs. Volanesorsen, is an antisense oligonucleotid that inhibits the production of the Apo C-III which is crucial in regulating TGs metabolism because it inhibits lipoprotein lipase (LPL) and hepatic lipase activity but also hepatic uptake of TGs-rich particles. Evinacumab is a monoclonal antibody against angiopoietin-like protein 3 (ANGPTL3) and it seems that it can substantially lower elevated TGs levels because ANGPTL3 also regulates TGs metabolism. Pemafibrate is a selective peroxisome proliferator-activated receptor alpha modulator which also decreases TGs, and improves other lipid parameters. It seems that it also has some other possible antiatherogenic effects. Alipogene tiparvovec is a nonreplicating adeno-associated viral vector that delivers copies of the LPL gene to muscle tissue which accelerates the clearance of TG-rich lipoproteins thus decreasing extremely high TGs levels. Pradigastat is a novel diacylglycerol acyltransferase 1 inhibitor which substantially reduces extremely high TGs levels and appears to be promising in treatment of the rare familial chylomicronemia syndrome.
الموضوعات
Apolipoprotein C-III , Cardiovascular Diseases , Diacylglycerol O-Acyltransferase , Fatty Acids, Omega-3 , Fibric Acids , Hyperlipoproteinemia Type I , Life Style , Lipase , Lipoprotein Lipase , Lipoproteins , Metabolism , Mortality , PPAR alpha , Risk Factors , Triglyceridesالملخص
Abstract Background Peroxisome proliferator activated receptor alpha (PPARα), a regulator of enzymes involved in β oxidation, has been reported to influence lymphocyte activation. The purpose of this study was to determine whether PPARα plays a role in T cell-mediated hepatitis induced by Concanavalin A (ConA). Methods Wild type (wt) or PPARα-deficient (PPARα−/−) mice were treated with ConA (15 mg/kg) by intravenous injection 0, 10 or 24 h prior to sacrifice and serum and tissue collection for analysis of tissue injury, cytokine response, T cell activation and characterization. Results Ten and 24 h following ConA administration, wt mice had significant liver injury as demonstrated by serum transaminase levels, inflammatory cell infiltrate, hepatocyte apoptosis, and expression of several cytokines including interleukin 4 (IL4) and interferon gamma (IFNγ). In contrast, PPARα−/− mice were protected from ConA-induced liver injury with significant reductions in serum enzyme release, greatly reduced inflammatory cell infiltrate, hepatocellular apoptosis, and IFNγ expression, despite having similar levels of hepatic T cell activation and IL4 expression. This resistance to liver injury was correlated with reduced numbers of hepatic natural killer T (NKT) cells and their in vivo responsiveness to alpha-galactosylceramide. Interestingly, adoptive transfer of either wt or PPARα−/− splenocytes reconstituted ConA liver injury and cytokine production in lymphocyte-deficient, severe combined immunodeficient mice implicating PPARα within the liver, possibly through support of IL15 expression and/or suppression of IL12 production and not the lymphocyte as the key regulator of T cell activity and ConA-induced liver injury. Conclusion Taken together, these data suggest that PPARα within the liver plays an important role in ConA-mediated liver injury through regulation of NKT cell recruitment and/or survival.
الموضوعات
Animals , Male , Mice , T-Lymphocytes/immunology , Cytokines/immunology , Macrolides/toxicity , Hepatitis, Autoimmune/etiology , PPAR alpha/immunology , Galactosylceramides/immunology , Enzyme-Linked Immunosorbent Assay , Immunohistochemistry , Hepatitis, Autoimmune/immunology , Disease Models, Animal , Real-Time Polymerase Chain Reaction , Mice, Inbred C57BLالملخص
Abstract Background Macrophages are a functionally heterogeneous cell population and depending on microenvironments they polarize in two main groups: M1 and M2. Glutamic acid and glutamate receptors may participate in the regulation of macrophage plasticity. To investigate the role of glutamatergic systems in macrophages physiology, we performed the transfection of mGluR5 cDNAs into RAW-264.7 cells. Results Comparative analysis of modified (RAW-mGluR5 macrophages) and non-modified macrophages (RAW-macrophages) has shown that the RAW-mGluR5 macrophages absorbed more glutamate than control cells and the amount of intracellular glutamate correlated with the expression of excitatory amino acid transporters -2 (EAAT-2). Besides, our results have shown that RAW-mGluR5 macrophages expressed a higher level of peroxisome proliferator-activated receptor γ (PPAR-γ) and secreted more IL-10, high mobility group box 1 proteins (HMGB1) and Galectin-3 than control RAW-macrophages. Conclusions We propose that elevation of intracellular glutamate and expression of mGluR5 may initiate the metabolic rearrangement in macrophages that could contribute to the formation of an immunosuppressive phenotype.
الموضوعات
Animals , Mice , Receptor, Metabotropic Glutamate 5/physiology , Cell Plasticity/physiology , Macrophages/physiology , Phenotype , Enzyme-Linked Immunosorbent Assay , Transfection/methods , Cells, Cultured , Lipopolysaccharides , Blotting, Western , Interleukin-10/analysis , Interleukin-10/metabolism , Glutamic Acid/analysis , Glutamic Acid/metabolism , HMGB1 Protein/analysis , HMGB1 Protein/metabolism , Galectin 3/analysis , Galectin 3/metabolism , PPAR alpha/analysis , PPAR alpha/metabolism , RAW 264.7 Cells , Nitric Oxide/metabolismالملخص
OBJECTIVE: Exercise is a protective factor for cardiovascular morbidity and mortality, with unclear mechanisms. Changing the myocardial metabolism causes harmful consequences for heart function and exercise contributes to metabolic adjustment modulation. Peroxisome proliferator-activated receptors (PPARs) are also myocardium metabolism regulators capable of decreasing the inflammatory response. We hypothesized that PPAR-α is involved in the beneficial effects of previous exercise on myocardial infarction (MI) and cardiac function, changing the expression of metabolic and inflammatory response regulators and reducing myocardial apoptosis, which partially explains the better outcome. METHODS AND RESULTS: Exercised rats engaged in swimming sessions for 60 min/day, 5 days/week, for 8 weeks. Both the exercised rats and sedentary rats were randomized to MI surgery and followed for 1 week (EI1 or SI1) or 4 weeks (EI4 or SI4) of healing or to sham groups. Echocardiography was employed to detect left ventricular function and the infarct size. Additionally, the TUNEL technique was used to assess apoptosis and immunohistochemistry was used to quantitatively analyze the PPAR-α, TNF-α and NF-κB antigens in the infarcted and non-infarcted myocardium. MI-related mortality was higher in SI4 than in EI4 (25% vs 12%), without a difference in MI size. SI4 exhibited a lower shortening fraction than EI4 did (24% vs 35%) and a higher apoptosis/area rate (3.97±0.61 vs 1.90±1.82) in infarcted areas (both p=0.001). Immunohistochemistry also revealed higher TNF-α levels in SI1 than in EI1 (9.59 vs 4.09, p<0.001) in infarcted areas. In non-infarcted areas, EI4 showed higher levels of TNF-α and positive correlations between PPAR-α and NF-κB (r=0.75, p=0.02), in contrast to SI4 (r=0.05, p=0.87). CONCLUSION: Previously exercised animals had better long-term ventricular function post-MI, in addition to lower levels of local inflammatory markers and less myocardial apoptosis, which seemed to be related to the presence of PPAR-α.
الموضوعات
Animals , Female , Myocardial Infarction/metabolism , PPAR alpha/metabolism , Physical Conditioning, Animal/physiology , Apoptosis/physiology , Inflammation/metabolism , Models, Animal , Myocardial Infarction/pathology , Myocardial Infarction , NF-kappa B/metabolism , PPAR alpha/analysis , Random Allocation , Rats, Wistar , Time , Tumor Necrosis Factor-alpha/metabolism , Ventricular Function/physiologyالملخص
<p><b>OBJECTIVE</b>To investigate the roles of microRNA-21 (miR-21) in the pathogenesis of non-alcoholic fatty liver disease (NAFLD) with high-fat diet-induced insulin resistance (IR) and diabetes mellitus (DM) mice model.</p><p><b>METHODS</b>Eight-week-old C57BL/6 mice were allocated into control group, IR group, and DM group. Body mass was recorded. Intraperitoneal glucose tolerance test was performed to determine any abnormal glucose metabolism. The liver pathological changes were detected by biopsy. Changes in free blood glucose, free serum insulin, blood fat and tumor necrosis factor Α level were measured. Differences in miR-21 expression and peroxidase proliferator-activated receptor subtypes (PPAR-Γ and PPAR-Α) and adipocyte fatty acid binding protein (aP2) in the liver were detected both at the mRNA and protein levels.</p><p><b>RESULTS</b>After one 8-week high-fat diet, the body mass, free serum insulin, and homeostasis model IR index significantly increased in the IR group (P<0.01, P<0.05, compared with control group), while the free blood glucose increased and the free serum insulin decreased in DM group (P<0.05). Free serum insulin level were significantly increased in IR group (P<0.05). Serum tumor necrosis factor-Α levels exhibited an upward trend in control group, IR group, and DM group (P<0.05, P<0.01). With exacerbation in NAFLD, liver miR-21 expression level went further down in both IR and DM groups (P<0.05). The downregulated miR-21 expression level showed negative correlation with upregulated PPAR-Α, ΑP2, and PPAR-Γ genetic expression (r=-0.696, r=-0.664, and r=-0.766, respectively; P<0.05) in IR group and with upregulated PPAR-Α and PPAR-Γ genetic expression in DM group (r=-0.676 and r=-0.550, respectively; P<0.05). In terms of the changes in protein expression level,only on the protein expressions of aP2 and PPAR-Γ in IR group showed significant change (P<0.05, P<0.01, compared with control group).</p><p><b>CONCLUSIONS</b>The miR-21 expression is downregulated in both IR and DM-induced NAFLD mice. It may be involved in the pathogenesis of NAFLD by regulating the expressions of PPAR subtypes.</p>
الموضوعات
Animals , Mice , Blood Glucose , Diabetes Mellitus, Experimental , Diet, High-Fat , Disease Models, Animal , Insulin , Blood , Insulin Resistance , Mice, Inbred C57BL , MicroRNAs , Metabolism , Non-alcoholic Fatty Liver Disease , PPAR alpha , Metabolism , PPAR gamma , Metabolism , Tumor Necrosis Factor-alpha , Metabolismالملخص
OBJECTIVE: To determine peroxisome proliferator activated receptor α and γ mRNA expression in liver tissue of hepatitis C virus-infected patients with and without human immunodeficiency virus and its possible contribution to an acceleration of liver disease progression. METHODS: We measured peroxisome proliferator-activated receptor α and γ mRNA expression by real-time polymerase chain reaction in liver tissues from 40 subjects infected only with hepatitis C virus, 36 subjects co-infected with hepatitis C virus and human immunodeficiency virus and 11 normal adults. RESULTS: Hepatic mRNA expression of both peroxisome proliferator-activated receptors was significantly lower in hepatitis C virus-infected subjects with and without human immunodeficiency virus co-infection compared to the controls. Non-black race was also identified as a predictor of lower peroxisome receptor α and γ mRNA expression. Compared to subjects infected only with hepatitis C virus, liver peroxisome receptor γ mRNA expression was significantly lower in hepatitis C virus/human immunodeficiency virus-co-infected subjects (0.0092 in hepatitis C virus/human immunodeficiency virus-co-infection vs. 0.0120 in hepatitis C virus-only; p=0.004). Hepatic peroxisome receptor α mRNA expression in the hepatitis C virus-infected patients was lower in the presence of human immunodeficiency virus co-infection in non-black subjects (0.0769 vs. 0.1061; p=0.02), whereas the levels did not vary based on human immunodeficiency virus status among black subjects. CONCLUSION: mRNA expression of both peroxisome proliferator-activated receptors is impaired in hepatitis C virus-infected liver and further reduced by human immunodeficiency virus co-infection, although the suppressive effects of the viruses are substantially mitigated in black patients.
الموضوعات
Adult , Aged , Female , Humans , Male , Middle Aged , Coinfection/pathology , HIV Infections/pathology , Hepatitis C, Chronic/pathology , PPAR alpha/analysis , PPAR gamma/analysis , RNA, Messenger/analysis , Analysis of Variance , Biopsy , Cross-Sectional Studies , Coinfection/complications , Coinfection/ethnology , HIV Infections/complications , HIV Infections/ethnology , Hepatitis C, Chronic/complications , Hepatitis C, Chronic/ethnology , Linear Models , Liver Cirrhosis/etiology , Liver Cirrhosis/pathology , Liver/pathology , PPAR alpha/genetics , PPAR gamma/genetics , Real-Time Polymerase Chain Reaction , Reference Values , Severity of Illness Indexالملخص
<p><b>OBJECTIVE</b>To investigate the effect of peroxisiome proliferator activated receptor-α (PPAR-α) on the regulation of cardiomyocyte hypertrophy and the relationship between the effect of PPAR-α with PI3K/Akt//mTOR signal pathway.</p><p><b>METHODS</b>Cardiomyocyte hypertrophy was induced by isoproterenol (ISO). The cell surface area was measured by image analysis system (Leica). The expressions of atrial natriuretic peptide (ANP), β-myosin heavy chain (β-MHC) and PPAR-α mRNA were detected by qRT-PCR. The protein expressions of Akt, mTOR and P70S6K were detected by Western blot. The expression of PPAR-α was suppressed by RNAi.</p><p><b>RESULTS</b>(1) The expression of PPAR-α was significantly reduced in cardiomyocyte hypertrophy. PPAR-α activator Fenofibrate (Feno) increased the expression of PPAR-α and suppressed cardiomyocyte hypertrophy. The inhibitory effect of Feno on cardiomyocyte hypertrophy was reversed by PPAR-α RNAi. (2) Feno significantly inhibited the increase of the protein expressions of p-Akt, p-mTOR and p-p70S6K in ISO induced cardiomyocyte hypertrophy, which could be blocked by PPAR-α RNAi. (3) PI3K antagonist LY294002 (LY) or mTOR antagonist rapamycin (RAPA) markedly-inhibited cardiomyocyte hypertrophy. The inhibitory effects of LY or RAPA on cardiomyocyte hypertrophy were reversed by PPAR-α RNAi.</p><p><b>CONCLUSION</b>PPAR-α can negatively regulate cardiomyocyte hypertrophy. The effect might be associated with PPAR-α inhiting PI3K/ Akt/mTOR signal pathway.</p>
الموضوعات
Humans , Atrial Natriuretic Factor , Metabolism , Cardiomegaly , Metabolism , Cells, Cultured , Fenofibrate , Pharmacology , Isoproterenol , Myocytes, Cardiac , Metabolism , Myosin Heavy Chains , Metabolism , PPAR alpha , Metabolism , Phosphatidylinositol 3-Kinases , Metabolism , Proto-Oncogene Proteins c-akt , Metabolism , RNA, Messenger , Ribosomal Protein S6 Kinases, 70-kDa , Metabolism , Signal Transduction , TOR Serine-Threonine Kinases , Metabolismالملخص
<p><b>OBJECTIVE</b>To detect the expression of the plateau adaptablity gene(EPAS1, EGLN1 and PPARα) and proteins(HIF-2, PHD2 and PPARα) in rats blood, heart, liver, lung and kidney tissue after the rats exposed to high altitude.</p><p><b>METHODS</b>The Wistar rats were randomly divided into plain group(Shanghai, 55 m), acute exposure to high altitude 3400 m group, acute exposure to high altitude 4300 m group. Blood and organs of rats were collected in 1, 3, 5 days after arrival. Real time PCR and ELISA were used to compare the expression of plateau adaptablity gene and related protein between plain group and high altitude exposure groups.</p><p><b>RESULTS</b>The count of red blood cells, hemoglobin and HCT in high altitude 4300 m were higher than those in plain group. Compared with plain group, the expression of EPAS1 gene in blood, heart, liver and kidney tissue of rats at high altitude increased obviously(all P<0.05); the expression of EGLN1 in the heart, liver, brain and kidney increased, and PPARα gene in the heart, liver and kidney increased(all P<0.05). Compared with plain group, the expression of HIF-2 protein increased significantly at high altitudes in the liver, brain and kidney tissues. PHD2 and PPARα increased in the heart, liver and kidney.</p><p><b>CONCLUSION</b>Plateau adaptive genes(EPAS1, EGLN1 and PPARα) and protein(HIF-2, PHD2 and PPARα) differed in different altitude and different organizations. They might be used as target markers of plateau hypoxia.</p>
الموضوعات
Animals , Rats , Adaptation, Physiological , Altitude , Basic Helix-Loop-Helix Transcription Factors , Metabolism , Brain , China , Heart , Hypoxia , Hypoxia-Inducible Factor-Proline Dioxygenases , Metabolism , Kidney , Liver , Lung , PPAR alpha , Metabolism , Procollagen-Proline Dioxygenase , Metabolism , Rats, Wistarالملخص
<p><b>OBJECTIVE</b>To investigate the association between ten single nucleotide polymorphisms (SNPs) in the peroxisome proliferator-activated receptors (PPARα, β, γ) with apolipoprotein A I/apolipoprotein B100 (ApoA I/ApoB100) ratio and the additional role of a gene-gene interactions among the 10 SNPs.</p><p><b>METHODS</b>Participants were recruited under the framework of the Prevention of Multiple Metabolic Disorders and Metabolic Syndrome in Jiangsu Province (PMMJS) cohort population survey in the urban community of Jiangsu province of China.A total of 630 subjects were randomly selected and no individual was related.Ten SNPs (rs135539, rs4253778, rs1800206, rs2016520, rs9794, rs10865710, rs1805192, rs709158, rs3856806 and rs4684847) were selected from the HapMap database,which covered PPARα, PPARβ and PPARγ. A linear regression model was used to analyze the relations between ten SNPs in the PPARs and ApoA I/ApoB100 ratio level. Mean difference and 95% CI were calculated. Interactions were explored by using the method of Generalized Multifactor Dimensionality Reduction (GMDR).</p><p><b>RESULTS</b>After adjusting for age, gender, smoking status, alcohol consumption, occupational physical activity, high-fat diet as well as low-fiber diet, both rs1800206 and rs3856806 were significantly associated with a decreased level of ApoA I/ApoB100 ratio, mean difference (95% CI) values were -1.19 (-1.88 to -0.50) and -0.77 (-1.40 to -0.14). Whereas rs4253778 was significantly associated with an increased level of ApoA I/ApoB100 ratio, Mean difference (95% CI) values was 0.80 (0.08 to 1.52). GMDR analysis showed a significant gene-gene interaction among rs4253778, rs1800206 of PPARα, rs9794, rs2016520 of PPARβ and rs10865710, rs3856806, rs709158, rs1805192 of PPARγ for eight-dimension models (P = 0.01), in which prediction accuracy was 0.624 and cross-validation consistency was 7/10.</p><p><b>CONCLUSIONS</b>The rs1800206 of PPARα and rs3856806 of PPARγ are significantly associated with a decreased level of ApoA I/ApoB100 ratio while rs4253778 of PPARα is associated with an increased level of ApoA I/ApoB100 ratio. There is a gene-gene interaction between multiple SNPs.</p>
الموضوعات
Humans , Apolipoprotein A-I , Genetics , Apolipoprotein B-100 , Genetics , China , Diet, High-Fat , Epistasis, Genetic , Gene Frequency , Genotype , Metabolic Syndrome , PPAR alpha , Genetics , PPAR delta , PPAR gamma , Genetics , Polymorphism, Single Nucleotideالملخص
<p><b>OBJECTIVE</b>To investigate the effect of apigenin on the protein expression levels of peroxisome proliferator-activated receptors (PPARs) in liver tissues of rats with nonalcoholic steatohepatitis (NASH).</p><p><b>METHODS</b>The NASH rat model was established by feeding of a high-fat diet. Unmodeled rats served as the normal controls. The modeled rats were divided into a model control group, Essentiale treatment grouP(300 mg/kg/day),and three apigenin treatment groups for low-dose (15 mg/kg/day), moderate-dose (30 mg/kg/day) and high-dose (60 mg/kg/day). After 13 weeks of treatment,changes in insulin sensitivity from pre-treatment baseline were assessed by measuring the alanine aminotransferase (ALT), aspartate aminotransferase (AST),total cholesterol (TC),triglycerides (TG),low-density and high-density lipoprotein cholesterol (LDL-C and HDL-C),fasting blood glucose (FBG) and fasting insulin (FINS).The liver index and HOMA-IR were also calculated.Protein and gene expression of PPARα and PPARgamma in liver tissue were assessed by immunohistochemistry and RT-PCR.Statistical analysis was performed by the LSD test and Games-Howell test.</p><p><b>RESULTS</b>The apigenin-treated groups showed a significantly greater change in insulin sensitivity than the untreated model group,with the most significant change occurring in the high-dose grouP(P less than 0.05).Compared with the untreated model group,the apigenin-treated groups showed lower levels of ALT (95.4+/-7.3),AST (183.7+/-14.3),TC (1.61+/-0.25),TG (1.23+/-0.21),LDL-C (1.86+/-0.14),FBG (5.29+/-1.45) and FINS (0.76+/-0.86),but a higher level of HDL-C (1.04+/-0.17); again,the high-dose group showed the greatest change (all P less than 0.05).Compared to the untreated model group,the apigenin-treated groups showed significantly lower liver index (3.75+/-0.25 vs.2.90+/-0.17) and HOMA-IR (1.34+/-0.06 vs.0.18+/-0.04),with the high-dose group showing the greatest change (both P less than 0.05). Compared to the untreated model group,the apigenin-treated groups showed higher levels of protein and mRNA of PPARα (18.27+/-4.05 and 0.63+/-0.02,respectively) and PPARgamma(8.48+/-5.05 and 0.39+/-0.02),with the high-dose group showing the greatest change (all P < 0.05).</p><p><b>CONCLUSION</b>Apigenin can improve glucose tolerance,lipid metabolism and insulin resistance while decreasing blood levels of TC,TG,LDL-C,FBG,FINS and HOMA-IR,and increasing HDL-C in NASH,as shown in a high-fat diet induced rat model, and may have therapeutic potential.</p>