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1.
Nat Immunol ; 22(2): 205-215, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33398183

RESUMO

Cancer and chronic infections induce T cell exhaustion, a hypofunctional fate carrying distinct epigenetic, transcriptomic and metabolic characteristics. However, drivers of exhaustion remain poorly understood. As intratumoral exhausted T cells experience severe hypoxia, we hypothesized that metabolic stress alters their responses to other signals, specifically, persistent antigenic stimulation. In vitro, although CD8+ T cells experiencing continuous stimulation or hypoxia alone differentiated into functional effectors, the combination rapidly drove T cell dysfunction consistent with exhaustion. Continuous stimulation promoted Blimp-1-mediated repression of PGC-1α-dependent mitochondrial reprogramming, rendering cells poorly responsive to hypoxia. Loss of mitochondrial function generated intolerable levels of reactive oxygen species (ROS), sufficient to promote exhausted-like states, in part through phosphatase inhibition and the consequent activity of nuclear factor of activated T cells. Reducing T cell-intrinsic ROS and lowering tumor hypoxia limited T cell exhaustion, synergizing with immunotherapy. Thus, immunologic and metabolic signaling are intrinsically linked: through mitigation of metabolic stress, T cell differentiation can be altered to promote more functional cellular fates.


Assuntos
Linfócitos T CD8-Positivos/metabolismo , Metabolismo Energético , Ativação Linfocitária , Linfócitos do Interstício Tumoral/metabolismo , Melanoma Experimental/metabolismo , Mitocôndrias/metabolismo , Microambiente Tumoral , Animais , Linfócitos T CD8-Positivos/imunologia , Linhagem Celular Tumoral , Técnicas de Cocultura , Feminino , Células HEK293 , Humanos , Linfócitos do Interstício Tumoral/imunologia , Masculino , Melanoma Experimental/genética , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Mitocôndrias/imunologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Fator 1 de Ligação ao Domínio I Regulador Positivo/genética , Fator 1 de Ligação ao Domínio I Regulador Positivo/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Hipóxia Tumoral
2.
Gene ; 774: 145422, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33450350

RESUMO

BACKGROUND: Leptin (LEP), leptin receptor (LEPR) and peroxisome proliferator-activated receptor gamma co-activator 1-alpha (PGC1A) are involved in the pathogenesis of multiple sclerosis (MS) by affecting the inflammatory response and reactive oxygen species production. LEP rs7799039 and LEPR rs1137101 genetic variants modify the serum LEP levels and PGC1A rs8192678 alters the PGC1A activity. The study objective was to explore the associations of these variants with susceptibility to MS, disease course/clinical parameters and also with peripheral blood mononuclear cell expression of the target genes and plasma LEP concentrations, in the study subjects. METHODS: The study groups included 528 patients with MS and 429 controls. TaqMan® assays were used for genotyping and gene expression quantification. The Chi-square, parametric and nonparametric tests and simple/multiple logistic regression were performed for the statistical analysis of data. RESULTS: A multiple logistic regression model including all three investigated variants, applied to patients (RRMS + SPMS) and controls, showed that PGC1A rs8192678 minor allele had an increased risk for the occurrence of disease, with OR (95%CI) = 1,32 (1,01-1,73), P = 0,04. Between-effect of gender and LEPR variant on the multiple sclerosis severity score (MSSS) was identified (P = 0,005). In male patients (relapsing-remitting and secondary progressive), LEPR minor allele carriers had increased MSSS (GG + AG vs AA, median (minimum-maximum) = 5,38 (0,64-9,88) vs 4,27 (0,78-9,63); P = 0,01, Padj = 0,03). In relapsing-remitting patients LEP rs7799039 affected the LEP gene expression (P = 0,006; Padj = 0,04). CONCLUSION: The current findings implicate an impact of investigated genetic variants on the pathogenesis of MS.


Assuntos
Leptina/genética , Esclerose Múltipla/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Polimorfismo de Nucleotídeo Único , Receptores para Leptina/genética , Adulto , Estudos de Casos e Controles , Feminino , Expressão Gênica , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Leptina/sangue , Leucócitos Mononucleares , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente , Reação em Cadeia da Polimerase em Tempo Real
3.
Drug Discov Ther ; 14(6): 304-312, 2021 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-33390570

RESUMO

Acute graft-versus-host disease (aGvHD) remains lethal as a life-threatening complication after allogeneic hematopoietic stem cell transplantation (HSCT). Inflammatory responses play an important role in aGvHD. 5-Aminolevulinic acid combined with sodium ferrous citrate (5-ALA/SFC) has been widely reported to have a major effect on the anti-inflammatory response; however, these effects in aGvHD models have never been reported. In this study, a murine aGvHD model was developed by transferring spleen cells from donor B6/N (H-2kb) mice into recipient B6D2F1 (H-2kb/d) mice. In addition to evaluating manifestations in aGvHD mice, we analyzed the serum ALT/AST levels, liver pathological changes, infiltrating cells and mRNA expression of inflammation-related cytokines and chemokines. 5-ALA/SFC treatment significantly ameliorated liver injury due to aGvHD and decreased the population of liver-infiltrating T cells, resulting in a reduced expression of pro-inflammatory cytokines and chemokines. Furthermore, the mRNA expression proliferator-activated receptor-γcoactivator (PGC-1α) was enhanced, which might explain why 5-ALA/SFC treatment downregulates inflammatory signaling pathways. Our results indicated that 5-ALA/SFC can ameliorate liver injury induced by aGvHD through the activation of PGC-1α and modulation of the liver mRNA expression of inflammatory-related cytokines and chemokines. This may be a novel strategy for treating this disease.


Assuntos
Citocinas/genética , Compostos Ferrosos/administração & dosagem , Doença Enxerto-Hospedeiro/tratamento farmacológico , Ácidos Levulínicos/administração & dosagem , Fígado/efeitos dos fármacos , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Regulação para Cima , Alanina Transaminase/sangue , Animais , Aspartato Aminotransferases/sangue , Modelos Animais de Doenças , Quimioterapia Combinada , Compostos Ferrosos/química , Compostos Ferrosos/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Doença Enxerto-Hospedeiro/etiologia , Doença Enxerto-Hospedeiro/genética , Ácidos Levulínicos/farmacologia , Fígado/imunologia , Fígado/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Citrato de Sódio/química , Linfócitos T/metabolismo , Resultado do Tratamento
4.
Phytomedicine ; 80: 153369, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33070082

RESUMO

BACKGROUND: Impairment of mitochondrial biogenesis is associated with the pathological progression of Parkinson's disease (PD). Parkin-interacting substrate (PARIS) can be ubiquitinated by parkin and prevents the repression of proliferator-activated receptor gamma coactivator-1-alpha (PGC-1α). PURPOSE: This study investigated whether the neuroprotective mechanism of carnosic acid (CA) from rosemary is mediated via the regulation of PARIS and PGC-1α by parkin. METHODS: The Western blotting and RT-PCR were used to determine protein and mRNA, respectively. To investigate the protein-protein interaction of between PARIS and ubiquitin, the immunoprecipitation assay (IP assay) was utilized. Silencing of endogenous parkin or PGC-1α was performed by using transient transfection of small interfering RNA (siRNA). RESULTS: SH-SY5Y cells treated with 6-hydroxydopamine (6-OHDA) increased PARIS protein, decreased PGC-1α protein, and reduced protein and mRNA of mitochondrial biogenesis-related genes. CA pretreatment reversed the effects of 6-OHDA. By IP assay, the interaction of PARIS with ubiquitin protein caused by CA was stronger than that caused by 6-OHDA. Moreover, knockdown of parkin attenuated the ability of CA to reverse the 6-OHDA-induced increase in PARIS and decrease in PGC-1α expression. PGC-1α siRNA was used to investigate how CA influenced the effect of 6-OHDA on the modulation of mitochondrial biogenesis and apoptosis. In the presence of PGC-1α siRNA, CA could no longer significantly reverse the reduction of mitochondrial biogenesis or the induction of cleavage of apoptotic-related proteins by 6-OHDA. CONCLUSION: The cytoprotective of CA is related to the enhancement of mitochondrial biogenesis by inhibiting PARIS and inducing PGC-1α by parkin. The activation of PGC-1α-mediated mitochondrial biogenesis by CA prevents the degeneration of dopaminergic neurons, CA may have therapeutic application in PD.


Assuntos
Abietanos/farmacologia , Mitocôndrias/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Proteínas Repressoras/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Neurônios Dopaminérgicos/efeitos dos fármacos , Neurônios Dopaminérgicos/metabolismo , Humanos , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Biogênese de Organelas , Oxidopamina/toxicidade , Doença de Parkinson/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , RNA Interferente Pequeno/farmacologia , Fatores de Transcrição/metabolismo , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismo
5.
Artigo em Inglês | MEDLINE | ID: mdl-33010451

RESUMO

Different strategies to boost NAD+ levels are considered promising means to promote healthy aging and ameliorate dysfunctional metabolism. CD38 is a NAD+-dependent enzyme involved in the regulation of different cell functions. In the context of systemic energy metabolism, it has been demonstrated that brown adipocytes, the parenchymal cells of brown adipose tissue (BAT) as well as beige adipocytes that emerge in white adipose tissue (WAT) depots in response to catabolic conditions, are important to maintain metabolic homeostasis. In this study we aim to understand the functional relevance of CD38 for NAD+ and energy metabolism in BAT and WAT, also using a CD38-/- mouse model. During cold exposure, an increase in NAD+ levels occurred in BAT of wild type mice, together with a marked downregulation of CD38, as detected at the mRNA and protein level. CD38 downregulation was observed also in WAT of cold-exposed mice, where it was accompanied by a strong increase in NADP(H) levels. Accordingly, NAD kinase and glucose-6-phosphate dehydrogenase activities were enhanced in WAT (but not in BAT). Increased NAD+ levels were observed in BAT/WAT from CD38-/- compared with wild type mice, in line with CD38 being a major NAD+-consumer in AT. CD38-/- mice kept at 6 °C had higher levels of Ucp1 and Pgc-1α in BAT and WAT, and increased levels of phosphorylated hormone-sensitive lipase in BAT, compared with wild type mice. These results demonstrate that CD38, by modulating cellular NAD(P)+ levels, is involved in the regulation of thermogenic responses in cold-activated BAT and WAT.


Assuntos
ADP-Ribosil Ciclase 1/genética , Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Glicoproteínas de Membrana/genética , NADP/metabolismo , NAD/metabolismo , RNA Mensageiro/genética , Termogênese/genética , ADP-Ribosil Ciclase 1/deficiência , Adipócitos Bege/citologia , Adipócitos Bege/metabolismo , Adipócitos Marrons/citologia , Adipócitos Marrons/metabolismo , Tecido Adiposo Marrom/citologia , Tecido Adiposo Branco/citologia , Animais , Temperatura Baixa , Metabolismo Energético/genética , Regulação da Expressão Gênica , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Homeostase/genética , Glicoproteínas de Membrana/deficiência , Camundongos , Camundongos Knockout , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Fosforilação , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , RNA Mensageiro/metabolismo , Transdução de Sinais , Proteína Desacopladora 1/genética , Proteína Desacopladora 1/metabolismo
6.
Am J Physiol Renal Physiol ; 320(3): F262-F272, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33356954

RESUMO

Mitochondrial damage in renal tubular epithelial cells (RTECs) is a hallmark of endotoxin-induced acute kidney injury (AKI). Forkhead box O1 (FOXO1) is responsible for regulating mitochondrial function and is involved in several kidney diseases. Here, we investigated the effect of FOXO1 on endotoxin-induced AKI and the related mechanism. In vivo, FOXO1 downregulation in mouse RTECs and mitochondrial damage were found in endotoxin-induced AKI. Overexpression of FOXO1 by kidney focal adeno-associated virus (AAV) delivery improved renal function and reduced mitochondrial damage. Peroxisome proliferator-activated receptor-γ coactivator 1-α (PGC1-α), a master regulator of mitochondrial biogenesis and function, was reduced in endotoxin-induced AKI, but the reduction was reversed by FOXO1 overexpression. In vitro, exposure to LPS led to a decline in HK-2 cell viability, mitochondrial fragmentation, and mitochondrial superoxide accumulation, as well as downregulation of FOXO1, PGC1-α, and mitochondrial complex I/V. Moreover, overexpression of FOXO1 in HK-2 cells increased HK-2 cell viability and PGC1-α expression, and it alleviated the mitochondrial injury and superoxide accumulation induced by LPS. Meanwhile, inhibition of FOXO1 in HK-2 cells by siRNA treatment decreased PGC1-α expression and HK-2 cell viability. Chromatin immunoprecipitation assays and PCR analysis confirmed that FOXO1 bound to the PGC1-α promoter in HK-2 cells. In conclusion, downregulation of FOXO1 in RTECs mediated endotoxin-induced AKI and mitochondrial damage. Overexpression of FOXO1 could improve renal injury and mitochondrial dysfunction, and this effect occurred at least in part as a result of PGC1-α signaling. FOXO1 might be a potential target for the prevention and treatment of endotoxin-induced AKI.


Assuntos
Lesão Renal Aguda/metabolismo , Endotoxemia/complicações , Células Epiteliais/metabolismo , Proteína Forkhead Box O1/metabolismo , Túbulos Renais/metabolismo , Lesão Renal Aguda/etiologia , Lesão Renal Aguda/genética , Lesão Renal Aguda/patologia , Animais , Linhagem Celular , Modelos Animais de Doenças , Endotoxemia/induzido quimicamente , Células Epiteliais/ultraestrutura , Proteína Forkhead Box O1/genética , Humanos , Túbulos Renais/ultraestrutura , Lipopolissacarídeos , Masculino , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Transdução de Sinais
7.
Sheng Li Xue Bao ; 72(6): 804-816, 2020 Dec 25.
Artigo em Chinês | MEDLINE | ID: mdl-33349839

RESUMO

Disturbance of the energy balance, when the energy intake exceeds its expenditure, is a major risk factor for the development of metabolic syndrome (MS). The peroxisome proliferator activated receptor γ (PPARγ) coactivator-1α (PGC-1α) functions as a key regulator of energy metabolism and has become a hotspot in current researches. PGC-1α sensitively responds to the environmental stimuli and nutrient signals, and further selectively binds to different transcription factors to regulate various physiological processes, including glucose metabolism, lipid metabolism, and circadian clock. In this review, we described the gene and protein structure of PGC-1α, and reviewed its tissue-specific function in the regulation of energy homeostasis in various mammalian metabolic organs, including liver, skeletal muscle and heart, etc. At the meanwhile, we summarized the application of potential small molecule compounds targeting PGC-1α in the treatment of metabolic diseases. This review will provide theoretical basis and potential drug targets for the treatment of metabolic diseases.


Assuntos
Metabolismo Energético , Fatores de Transcrição , Animais , Homeostase , Metabolismo dos Lipídeos , Fígado/metabolismo , Músculo Esquelético/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
8.
Xi Bao Yu Fen Zi Mian Yi Xue Za Zhi ; 36(9): 788-793, 2020 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-32967762

RESUMO

Objective To investigate SIRT1-PGC-1α signaling pathway-mediated effect of hyperoxia on mitochondrial function in A549 human alveolar epithelial cells and its possible mechanism. Methods Human alveolar epithelial cells in logarithmic growth phase were randomly divided into control group and hyperoxia group. The control group was cultured in a 37DegreesCelsius, 50 mL/L CO2 saturated humidity incubator, and the hyperoxia group was treated with 950 mL/L O2. Following 24-hour culture, Mito SOXTM staining was used to detect the level of mitochondrial reactive oxygen species (Mito-ROS) and JC-1 staining to detect the mitochondrial membrane potential. Real-time quantitative PCR was performed to detect the mitochondrial DNA content and the mRNA levels of SIRT1, PGC-1α, nuclear respiratory factor 1 (NRF1) and mitochondrial transcription factor A (TFAM), and Western blotting to detect the protein levels of SIRT1, PGC-1α, NRF1 and TFAM. Results Compared with the control group, the Mito-ROS of the hyperoxia group increased significantly, while the membrane potential decreased obviously; the mitochondrial DNA content of the hyperoxia group went down, and the mRNA and protein expression of SIRT1, PGC-1α, NRF1 and TFAM dropped. Conclusion Hyperoxia induces mitochondrial dysfunction in human alveolar epithelial cells by inhibiting the expression of SIRT1 and PGC-1α.


Assuntos
Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Sirtuína 1/genética , Células Epiteliais Alveolares/metabolismo , Hipóxia Celular , Linhagem Celular , Regulação para Baixo , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Sirtuína 1/metabolismo
9.
Nat Commun ; 11(1): 4664, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938919

RESUMO

Cardiorenal syndrome type 4 (CRS4) is a common complication of chronic kidney disease (CKD), but the pathogenic mechanisms remain elusive. Here we report that morphological and functional changes in myocardial mitochondria are observed in CKD mice, especially decreases in oxidative phosphorylation and fatty acid metabolism. High phosphate (HP), a hallmark of CKD, contributes to myocardial energy metabolism dysfunction by downregulating peroxisome proliferator-activated receptor gamma coactivator 1 alpha (PGC1α). Furthermore, the transcriptional factor interferon regulatory factor 1 (IRF1) is revealed as the key molecule upregulated by HP through histone H3K9 acetylation, and responsible for the HP-mediated transcriptional inhibition of PGC1α by directly binding to its promoter region. Conversely, restoration of PGC1α expression or genetic knockdown of IRF1 significantly attenuates HP-induced alterations in vitro and in vivo. These findings demonstrate that IRF1-PGC1α axis-mediated myocardial energy metabolism remodeling plays a crucial role in the pathogenesis of CRS4.


Assuntos
Síndrome Cardiorrenal/metabolismo , Fator Regulador 1 de Interferon/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Síndrome Cardiorrenal/patologia , Modelos Animais de Doenças , Regulação para Baixo , Metabolismo Energético , Técnicas de Silenciamento de Genes , Taxa de Filtração Glomerular , Glucuronidase/genética , Insuficiência Cardíaca/etiologia , Insuficiência Cardíaca/metabolismo , Humanos , Fator Regulador 1 de Interferon/genética , Masculino , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , Camundongos Knockout , Pessoa de Meia-Idade , Mitocôndrias Cardíacas/metabolismo , Mitocôndrias Cardíacas/patologia , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Fosfatos/metabolismo , Regiões Promotoras Genéticas , Ratos , Insuficiência Renal Crônica/complicações , Insuficiência Renal Crônica/metabolismo , Adulto Jovem
10.
Ecotoxicol Environ Saf ; 205: 111089, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32810645

RESUMO

Early molecular events after the exposure of heavy metals, such as aberrant DNA methylation, suggest that DNA methylation was important in regulating physiological processes for animals and accordingly could be used as environmental biomarkers. In the present study, we found that copper (Cu) exposure increased lipid content and induced the DNA hypermethylation at the whole genome level. Especially, Cu induced hypermethylation of glucose-regulated protein 78 (grp78) and peroxisome proliferator-activated receptor gamma coactivator-1α (pgc1α). CCAAT/enhancer binding protein α (C/EBPα) could bind to the methylated sequence of grp78, whereas C/EBPß could not bind to the methylated sequence of grp78. These synergistically influenced grp78 expression and increased lipogenesis. In contrast, DNA methylation of PGC1α blocked the specific protein 1 (SP1) binding and interfered mitochondrial function. Moreover, Cu increased reactive oxygen species (ROS) production, activated endoplasmic reticulum (ER) stress and damaged mitochondrial function, and accordingly increased lipid deposition. Notably, we found a new toxicological mechanism for Cu-induced lipid deposition at DNA methylation level. The measurement of DNA methylation facilitated the use of these epigenetic biomarkers for the evaluation of environmental risk.


Assuntos
Carpas/fisiologia , Cobre/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Carpas/metabolismo , Cobre/metabolismo , Estresse do Retículo Endoplasmático , Glucose/metabolismo , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Lipídeos , Metilação , Mitocôndrias/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Ativação Transcricional , Regulação para Cima
11.
Gene ; 763: 145071, 2020 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-32827682

RESUMO

The previous study indicated that transport stress resulted in oxidative damage and autophagy/mitophagy elevation, companied by NOX1 over- expression in the jejunal tissues of pigs. However, the transportation-related gene expression profile and NOX1 function in intestine remain to be explicated. In the current study, differentially expressed genes involved in PI3K-Akt and NF-κB pathways, oxidative stress and autophagy process have been identified in pig jejunal tissues after transcriptome analysis following transportation. The physiological functions of NOX1 down-regulation were explored against oxidative damage and excessive autophagy in porcine intestinal epithelial cells (IPEC-1) following NOX1 inhibitor ML171 and H2O2 treatments. NOX1 down-regulation could decrease the content of Malondialdehyde (MDA), Lactic dehydrogenase (LDH) activity and reactive oxygen species (ROS) level, and up-regulate superoxide dismutase (SOD) activity. Furthermore, mitochondrial membrane potential and content were restored, and the expressions of tight junction proteins (Claudin-1 and ZO-1) were also increased. Additionally, NOX1 inhibitior could down-regulate the expression of autophagy-associated proteins (ATG5, LC3, p62), accompanied by activating SIRT1/PGC-1α pathway. NOX1 down-regulation might alleviate oxidative stress-induced mitochondria damage and intestinal mucosal injury via modulating excessive autophagy and SIRT1/PGC-1α signaling pathway. The data will shed light on the molecular mechanism of NOX1 on intestine oxidative damage following pig transportation.


Assuntos
Autofagia , Enterócitos/metabolismo , NADPH Oxidase 1/metabolismo , Estresse Oxidativo , Estresse Psicológico/metabolismo , Transcriptoma , Animais , Linhagem Celular , Feminino , Masculino , Mitocôndrias/metabolismo , NADPH Oxidase 1/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Sirtuínas/genética , Sirtuínas/metabolismo , Estresse Psicológico/genética , Suínos
12.
Proc Natl Acad Sci U S A ; 117(36): 22204-22213, 2020 09 08.
Artigo em Inglês | MEDLINE | ID: mdl-32848060

RESUMO

The peroxisome proliferator-activated receptor gamma coactivator 1-alpha (PGC-1α) is a transcriptional coactivator that controls expression of metabolic/energetic genes, programming cellular responses to nutrient and environmental adaptations such as fasting, cold, or exercise. Unlike other coactivators, PGC-1α contains protein domains involved in RNA regulation such as serine/arginine (SR) and RNA recognition motifs (RRMs). However, the RNA targets of PGC-1α and how they pertain to metabolism are unknown. To address this, we performed enhanced ultraviolet (UV) cross-linking and immunoprecipitation followed by sequencing (eCLIP-seq) in primary hepatocytes induced with glucagon. A large fraction of RNAs bound to PGC-1α were intronic sequences of genes involved in transcriptional, signaling, or metabolic function linked to glucagon and fasting responses, but were not the canonical direct transcriptional PGC-1α targets such as OXPHOS or gluconeogenic genes. Among the top-scoring RNA sequences bound to PGC-1α were Foxo1, Camk1δ, Per1, Klf15, Pln4, Cluh, Trpc5, Gfra1, and Slc25a25 PGC-1α depletion decreased a fraction of these glucagon-induced messenger RNA (mRNA) transcript levels. Importantly, knockdown of several of these genes affected glucagon-dependent glucose production, a PGC-1α-regulated metabolic pathway. These studies show that PGC-1α binds to intronic RNA sequences, some of them controlling transcript levels associated with glucagon action.


Assuntos
Glucagon/metabolismo , Glucagon/farmacologia , Hepatócitos/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Proteínas de Ligação ao Cálcio/genética , Proteínas de Ligação ao Cálcio/metabolismo , Células Cultivadas , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/fisiologia , Gluconeogênese/fisiologia , Glucose/metabolismo , Guanosina Trifosfato/metabolismo , Fígado/metabolismo , Masculino , Metabolômica , Camundongos , Camundongos Endogâmicos C57BL , Proteínas de Transporte da Membrana Mitocondrial/genética , Proteínas de Transporte da Membrana Mitocondrial/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Ligação Proteica , Transcriptoma
13.
DNA Cell Biol ; 39(9): 1521-1531, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32721231

RESUMO

Previous studies suggested that alterations in the energy metabolism might be underlying cancer initiation and progression. Polymorphisms of genes involved in energy metabolism regulation, such as peroxisome proliferator-activated receptor gamma coactivator 1α (PPARGC1A), -ß (PPARGC1B), and paraoxonase 1 (PON1), might confer susceptibility to esophageal squamous cell carcinoma (ESCC) and partially explain its pathogenesis. We investigated the effects of several single nucleotide polymorphisms (SNPs) in three metabolic-related genes (e.g., PPARGC1A, PPARGC1B, and PON1) on ESCC susceptibility. In total, 829 patients with sporadic ESCC and 1522 nontumor controls were enrolled in the study. SNPs were genotyped using PCR-ligase detection reaction. Our study revealed that the PPARGC1A rs3736265 G/A SNP significantly increased the risk for ESCC (GA vs. GG: adjusted odds ratio [OR] = 1.25, 95% confidence interval [95% CI] = 1.02-1.54, p = 0.034; GA+AA vs. GG: adjusted OR = 1.25, 95% CI = 1.03-1.52, p = 0.027]. In addition, a stratified analysis revealed that the PPARGC1A rs3736265 SNP was correlated with the development of ESCC in male and nondrinking subgroups. We also confirmed that the PPARGC1B rs17572019 G/A SNP promoted the risk of ESCC in subgroup with high alcohol intake. The PPARGC1A rs8192678 C/T polymorphism decreased the susceptibility of ESCC in men. These findings highlight that polymorphisms in PPARGC1A and PPARGC1B may contribute to ESCC susceptibility. In the future, further well-designed epidemiological studies are needed to confirm our findings.


Assuntos
Arildialquilfosfatase/genética , Carcinoma de Células Escamosas/genética , Neoplasias Esofágicas/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Polimorfismo de Nucleotídeo Único , Proteínas de Ligação a RNA/genética , Idoso , China , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
14.
Life Sci ; 256: 117920, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32522571

RESUMO

AIM: We investigated the effects of high-intensity interval and continuous short-term exercise on body composition and cardiac function after myocardial ischemia-reperfusion injury (IRI) in obese rats. METHODS: Rats fed with a standard chow diet (SC) or high-fat diet (HFD) for 20 weeks underwent systolic blood pressure (SBP), glycemia and dual-energy X-ray absorptiometry analyses. Then, animals fed with HFD were subdivided into three groups: sedentary (HFD-SED); moderate-intensity continuous training (HFD-MICT); and high-intensity interval training (HFD-HIIT). Exercised groups underwent four isocaloric aerobic exercise sessions, in which HFD-MICT maintained the intensity continuously and HFD-HIIT alternated it. After exercise sessions, all groups underwent global IRI and myocardial infarct size (IS) was determined histologically. Fat and muscle mass were weighted, and protein levels involved in muscle metabolism were assessed in skeletal muscle. RESULTS: HFD-fed versus SC-fed rats reduced lean body mass by 31% (P < 0.001), while SBP, glycemia and body fat percentage were increased by 10% (P = 0.04), 30% (P = 0.006) and 54% (P < 0.001); respectively. HFD-induced muscle atrophy was restored in exercised groups, as only HFD-SED presented lower gastrocnemius (32%; P = 0.001) and quadriceps mass (62%; P < 0.001) than SC. PGC1-α expression was 2.7-fold higher in HFD-HIIT versus HFD-SED (P = 0.04), whereas HFD-HIIT and HFD-MICT exhibited 1.7-fold increase in p-mTORSer2481 levels compared to HFD-SED (P = 0.04). Although no difference was detected among groups for IS (P = 0.30), only HFD-HIIT preserved left-ventricle developed pressure after IRI (+0.7 mmHg; P = 0.9). SIGNIFICANCE: Short-term exercise, continuous or HIIT, restored HFD-induced muscle atrophy and increased mTOR expression, but only HIIT maintained myocardial contractility following IRI in obese animals.


Assuntos
Composição Corporal/fisiologia , Miocárdio/metabolismo , Animais , Glicemia/metabolismo , Pressão Sanguínea , Dieta Hiperlipídica , Regulação da Expressão Gênica , Testes de Função Cardíaca , Treinamento Intervalado de Alta Intensidade , Humanos , Estudos Longitudinais , Masculino , Modelos Animais , Músculo Esquelético/metabolismo , Infarto do Miocárdio/metabolismo , Traumatismo por Reperfusão Miocárdica/etiologia , Obesidade/etiologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Condicionamento Físico Animal , Ratos , Ratos Wistar , Sarcopenia/etiologia
15.
Life Sci ; 254: 117762, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32437795

RESUMO

AIMS: Patients with nonalcoholic fatty liver disease (NAFLD) have less tolerance to ischemia-reperfusion injury (IRI) of the liver than those with the healthy liver; hence have a higher incidence of severe complications after surgery. This study aimed to investigate the dynamics of the liver and mitochondrial damage and the impact of TLR4 knockout (TLR4KO) on Mfn2 expression in the composite model of NAFLD and IRI. MAIN METHODS: We performed high-fat diet (HFD) feeding and ischemia reperfusion (IR) on wild type (WT) and TLR4 knockout TLR4KO mice. KEY FINDINGS: The degree of structural and functional injuries to the liver and mitochondria (NAFLD and IRI) is greater than that caused by a single factor (NAFLD or IRI) or a simple superposition of both. The IL-6 and TNF-α expressions were significantly suppressed (P < .05), while PGC-1α and Mfn2 expressions were up-regulated considerably (P < .05) after TLR4KO. Furthermore, mitochondrial fusion increased, while ATP consumption and ROS production decreased significantly after TLR4KO (P < .05). The degree of reduction of compound injury by TLR4KO is more significant than the reduction degree of single factor injury. Also, TNF-α and IL-6 levels can be used predictive markers for mitochondrial damage and liver tolerance to NAFLD and IRI. SIGNIFICANCE: TLR4KO upregulates the expression of Mfn2 and PGC-1α in the composite model of NAFLD and IRI. This pathway may be related to IL-6 and TNF-α. This evidence provides theoretical and experimental basis for the subsequent Toll-like receptor 4 (TLR4) receptor targeted therapy.


Assuntos
GTP Fosfo-Hidrolases/biossíntese , Fígado/irrigação sanguínea , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/biossíntese , Traumatismo por Reperfusão/metabolismo , Receptor 4 Toll-Like/metabolismo , Animais , Dieta Hiperlipídica , Modelos Animais de Doenças , GTP Fosfo-Hidrolases/genética , GTP Fosfo-Hidrolases/metabolismo , Regulação da Expressão Gênica , Fígado/metabolismo , Fígado/patologia , Transplante de Fígado , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , NF-kappa B/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Reperfusão , Traumatismo por Reperfusão/patologia , Transdução de Sinais/fisiologia , Receptor 4 Toll-Like/deficiência , Receptor 4 Toll-Like/genética , Ativação Transcricional , Fator de Necrose Tumoral alfa/metabolismo , Regulação para Cima
16.
J Bone Miner Metab ; 38(5): 631-638, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32350615

RESUMO

INTRODUCTION: Disuse-induced bone loss is caused by a suppression of osteoblastic bone formation and an increase in osteoclastic bone resorption. There are few data available for the effects of environmental conditions, i.e., atmospheric pressure and/or oxygen concentration, on osteoporosis. This study examined the effects of mild hyperbaric oxygen at 1317 hPa with 40% oxygen on unloading-induced osteoporosis. MATERIALS AND METHODS: Eighteen 8-week old male Wistar rats were randomly divided into three groups: the control for 21 days without unloading and mild hyperbaric oxygen (NOR, n = 6), the unloading for 21 days and recovery for 10 days without mild hyperbaric oxygen (HU + NOR, n = 6), and the unloading for 21 days and recovery for 10 days with mild hyperbaric oxygen (HU + MHO, n = 6). RESULTS: The cortical thickness and trabecular bone surface area were decreased in the HU + NOR group compared to the NOR group. There were no differences between the NOR and HU + MHO groups. Osteoclast surface area and Sclerostin (Sost) mRNA expression levels were decreased in the HU + MHO group compared to the HU + NOR group. These results suggested that the loss of the cortical and trabecular bone is inhibited by mild hyperbaric oxygen, because of an inhibition of osteoclasts and enhancement of bone formation with decreased Sost expression. CONCLUSIONS: We conclude that exposure to mild hyperbaric oxygen partially protects from the osteoporosis induced by hindlimb unloading.


Assuntos
Elevação dos Membros Posteriores/fisiologia , Oxigenação Hiperbárica , Osteoporose/fisiopatologia , Osteoporose/terapia , Animais , Peso Corporal , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Osso Esponjoso/patologia , Osso Esponjoso/fisiopatologia , Osso Cortical/patologia , Osso Cortical/fisiopatologia , Marcadores Genéticos/genética , Lâmina de Crescimento/patologia , Masculino , Osteocalcina/genética , Osteocalcina/metabolismo , Osteoclastos/patologia , Osteoporose/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Ligante RANK/genética , Ligante RANK/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Wistar
17.
Obes Facts ; 13(2): 130-143, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32325455

RESUMO

BACKGROUND: Regular physical activity has an important role in energy expenditure and combats the development of obesity. During exercise, PPARGC1A is overexpressed, stimulating an increase of the expression of FNDC5. This protein is cleaved to release the hormone irisin, which activates a browning process in white adipose tissue through an increase in UCP1 expression. As a result, irisin leads to mitochondrial heat production and energy expenditure. OBJECTIVES: The aim of this study was to investigate whether genetic variants in genes related to browning are associated with severe obesity and obesity-related features. This case-control study comprised 210 individuals with severe obesity (median body mass index [BMI] 45.6 [range 40.5-52.2]) and 191 normal-weight subjects (BMI 22.8 [21.1-23.9]). METHODS: Genomic DNA was extracted from peripheral blood and the genotypes of the PPARGC1A(rs8192678, rs3736265, rs2970847, and rs3755863) and UCP1 (rs6536991 and rs12502572) genes were obtained using Taqman® assay. For the FNDC5 gene, screening of exons 3-5 as well as their intron-exon boundaries was performed using automatic sequencing. RESULTS: Our results demonstrated that PPARGC1Ars2970847 and UCP1rs12502572 are associated with severe obesity. Furthermore, these polymorphisms influence anthropometric traits, such as BMI, body weight, and body adiposity index. Our findings also showed a dose-effect relationship between PPARGC1A rs8192678 and fasting plasma glucose. Finally, 5 rare mutations were identified in FNDC5, and 1 of these is a novel missense mutation. CONCLUSION: This study shows that genetic variants in the activation of brown-like adipocyte pathway play an important role in the susceptibility to severe obesity.


Assuntos
Adipócitos Marrons/fisiologia , Adipócitos/fisiologia , Transdiferenciação Celular/genética , Fibronectinas/genética , Obesidade Mórbida/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Polimorfismo de Nucleotídeo Único , Tecido Adiposo Marrom/fisiologia , Tecido Adiposo Branco/metabolismo , Tecido Adiposo Branco/fisiologia , Adolescente , Adulto , Idoso , Índice de Massa Corporal , Estudos de Casos e Controles , Estudos Transversais , Metabolismo Energético/genética , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Mutação de Sentido Incorreto , Obesidade Mórbida/metabolismo , Obesidade Mórbida/fisiopatologia , Adulto Jovem
18.
Life Sci ; 249: 117501, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32142766

RESUMO

AIMS: Aldehyde reductase (AKR1A) is involved in the synthesis of ascorbic acid (AsA) as well as the detoxification of aldehydes. AKR1A-/- (KO) mice produce about 10% of the normal amounts of AsA compared to AKR1A+/+ (WT) mice. We investigated physiologic roles of AKR1A in running using the KO mice. MAIN METHODS: The KO mice were subjected to a treadmill test under either restricted AsA production or a sufficiency by supplementation and compared the results with those of WT mice. Contents of glucose, aspartate aminotransferase, AsA and free fatty acids in blood were measured. Glycogen contents were measured in the liver and skeletal muscle, and hepatic proteins were examined by immunoblot analyses. KEY FINDINGS: Running performance was higher in the KO mice than the WT mice irrespective of the AsA status. After the exercise period, blood glucose levels were decreased in the WT mice but were preserved in the KO mice. Liver glycogen levels were also consistently preserved in the KO mice after exercise. Free fatty acid levels tended to be originally high in blood plasma compared to those of the WT mice and were increased to similar extent in them. A key regulator of energy metabolism, PGC-1α, and the products of downstream target genes that encode for glyceraldehyde-3-phosphate dehydrogenase and glucose-6-phosphatase, were constitutively at high levels in the KO mice. SIGNIFICANCE: The genetic ablation of AKR1A activates the PGC-1α pathway and spare glucose, which would consequently confer exercise endurance.


Assuntos
Aldeído Redutase/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Condicionamento Físico Animal , Resistência Física , Aldeído Redutase/metabolismo , Animais , Glicemia/metabolismo , Metabolismo Energético , Ácidos Graxos não Esterificados/sangue , Metabolismo dos Lipídeos , Glicogênio Hepático/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética
19.
Int J Mol Sci ; 21(6)2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32183173

RESUMO

Increased oxidative stress and mitochondrial damage are observed in protein aggregation diseases, such as age-related macular degeneration (AMD). We have recently reported elevated levels of oxidative stress markers, damaged mitochondria, accumulating lysosomal lipofuscin and extracellular drusen-like structures in the retinal pigment epithelial cells (RPE) of the dry AMD-resembling NFE2L2/PGC1α double knockout (dKO) mouse model. Here, we provide evidence of a disturbance in the autolysosomal machinery handling mitochondrial clearance in the RPE cells of one-year-old NFE2L2/PGC1α-deficient mice. Confocal immunohistochemical analysis revealed an upregulation of autophagosome marker microtubule-associated proteins 1A/1B light chain 3B (LC3B) as well as numerous mitophagy markers, such as PTE-induced putative kinase 1 (PINK1) and E3 ubiquitin ligase (PARKIN) together with damaged mitochondria. However, we detected no evidence of increased autolysosome formation in transmission electron micrographs or of colocalization of lysosomal marker LAMP2 (lysosome-associated membrane protein 2) and the mitochondrial marker ATP synthase ß in confocal micrographs. Interestingly, we observed an upregulation of late autolysosomal fusion Ras-related protein (Rab7) in the perinuclear space of RPE cells together with autofluorescence aggregates. Our results reveal that there is at least a relative decrease of mitophagy in the RPE cells of NFE2L2/PGC1α dKO mice. This further supports the hypothesis that mitophagy is a putative therapy target in AMD-like pathology.


Assuntos
Degeneração Macular/metabolismo , Mitofagia , Fator 2 Relacionado a NF-E2/genética , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Epitélio Pigmentado da Retina/metabolismo , Animais , Deleção de Genes , Proteína 2 de Membrana Associada ao Lisossomo/metabolismo , Lisossomos/metabolismo , Lisossomos/ultraestrutura , Degeneração Macular/genética , Masculino , Camundongos , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/ultraestrutura , Proteínas Quinases/metabolismo , Epitélio Pigmentado da Retina/ultraestrutura , Ubiquitina-Proteína Ligases/metabolismo
20.
Int J Mol Sci ; 21(6)2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32178369

RESUMO

This study aimed at achieving the molecular characterization of peroxisome proliferator-activated receptor-gamma coactivator 1ß (PGC-1ß) and exploring its modulatory roles in mitochondria biogenesis in blunt snout bream (Megalobrama amblycephala). A full-length cDNA of PGC-1ß was cloned from liver which covered 3110 bp encoding 859 amino acids. The conserved motifs of PGC-1ß family proteins were gained by MEME software, and the phylogenetic analyses showed motif loss and rearrangement of PGC-1ß in fish. The function of PGC-1ß was evaluated through overexpression and knockdown of PGC-1ß in primary hepatocytes of blunt snout bream. We observed overexpression of PGC-1ß along with enhanced mitochondrial transcription factor A (TFAM) expression and mtDNA copies in hepatocytes, and its knockdown led to slightly reduced NRF1 expression. However, knockdown of PGC-1ß did not significantly influence TFAM expression or mtDNA copies. The alterations in mitochondria biogenesis were assessed following high-fat intake, and the results showed that it induces downregulation of PGC-1ß. Furthermore, significant decreases in mitochondrial respiratory chain activities and mitochondria biogenesis were observed by high-fat intake. Our findings demonstrated that overexpression of PGC-1ß induces the enhancement of TFAM expression and mtDNA amount but not NRF-1. Therefore, it could be concluded that PGC-1ß is involved in mitochondrial biogenesis in blunt snout bream but not through PGC-1ß/NRF-1 pathway.


Assuntos
Cyprinidae/genética , Cyprinidae/fisiologia , Mitocôndrias/genética , Mitocôndrias/fisiologia , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/genética , Aminoácidos , Animais , DNA Mitocondrial/genética , Proteínas de Ligação a DNA/genética , Hepatócitos/fisiologia , Fígado , Proteínas Mitocondriais/genética , Biogênese de Organelas , Filogenia , Transdução de Sinais/genética , Fatores de Transcrição/genética
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