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1.
Eur J Neurosci ; 60(5): 4843-4860, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39049535

RESUMO

Skeletal muscle wasting is a clinically proven pathology associated with Japanese encephalitis virus (JEV) infection; however, underlying factors that govern skeletal muscle damage are yet to be explored. The current study aims to investigate the pathobiology of skeletal muscle damage using a mouse model of JEV infection. Our study reveals a significant increment in viral copy number in skeletal muscle post-JEV infection, which is associated with enhanced skeletal muscle cell death. Molecular and biochemical analysis confirms NOX2-dependent generation of reactive oxygen species, leading to autophagy flux inhibition and cell apoptosis. Along with this, an alteration in mitochondrial dynamics (change in fusion and fission process) and a decrease in the total number of mitochondria copies were found during JEV disease progression. The study represents the initial evidence of skeletal muscle damage caused by JEV and provides insights into potential avenues for therapeutic advancement.


Assuntos
Vírus da Encefalite Japonesa (Espécie) , Encefalite Japonesa , Dinâmica Mitocondrial , Músculo Esquelético , Espécies Reativas de Oxigênio , Animais , Espécies Reativas de Oxigênio/metabolismo , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Músculo Esquelético/virologia , Camundongos , Encefalite Japonesa/metabolismo , Dinâmica Mitocondrial/fisiologia , Apoptose/fisiologia , NADPH Oxidase 2/metabolismo , NADPH Oxidase 2/genética , Autofagia/fisiologia , Modelos Animais de Doenças
2.
Environ Toxicol ; 39(2): 840-856, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37853854

RESUMO

INTRODUCTION: Hepatocellular carcinoma (HCC) is a common solid cancer and the leading cause of cancer deaths worldwide. Sorafenib is the first drug used to treat HCC but its effectiveness needs to be improved, and it is important to find ways to treat cancer that combine sorafenib with other drugs. Synergistic therapies lower effective drug doses and side effects while enhancing the anticancer effect. PURPOSE: In the present study, the therapeutic potential of sorafenib in combination with escin and its underlying mechanism in targeting liver cancer has been established. STUDY DESIGN/METHODS: The IC50 of sorafenib and escin against HepG2, PLC/PRF5 and Huh7 cell lines were determined using MTT assay. The combination index, dose reduction index, isobologram and concentrations producing synergy were evaluated using the Chou-Talaly algorithm. The sub-effective concentration of sorafenib and escin was selected to analyze cytotoxic synergistic potential. Cellular ROS, mitochondrial membrane potential, annexin V and cell cycle were evaluated using a flow-cytometer, and autophagy biomarkers were determined using western blotting. Moreover, autophagy was knocked down using ATG5 siRNA to confirm its role. A DEN-induced liver cancer rat model was developed to check the synergy of sorafenib and escin. RESULTS: Different concentrations of escin reduced the IC50 of sorafenib in HepG2, PLC/PRF5 and Huh7 cell lines. Chou-Talaly algorithm determined cytotoxic synergistic concentrations of sorafenib and escin in these cell lines. Mechanistically, this combination over-expressed p62 and LC-II, reflecting autophagy block and induced late apoptosis, further reconfirmed by ATG5 knockdown. Sorafenib and escin combination  reduced HCC serum biomarker α-feto protein (α-FP) by 1.5 folds. This combination restricted liver weight, tumor number and size, also, conserved morphological features of liver cells. The combination selectively targeted the G0 /G1 phase of cancer cells. CONCLUSION: Escin and sorafenib combination potentially up-regulates p62 to block autophagy to induce late apoptosis in liver cancer cells.


Assuntos
Antineoplásicos , Carcinoma Hepatocelular , Neoplasias Hepáticas , Animais , Ratos , Antineoplásicos/farmacologia , Apoptose , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Proliferação de Células , Escina/farmacologia , Neoplasias Hepáticas/patologia , Proteínas Associadas aos Microtúbulos , Sorafenibe/farmacologia
3.
Semin Cancer Biol ; 86(Pt 3): 1105-1121, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-34979274

RESUMO

Chemokines are small secretory chemotactic cytokines that control the directed migration of immune cells. Chemokines are involved in both anti-and pro-tumorigenic immune responses. Accumulating evidence suggests that the balance between these responses is influenced by several factors such as the stage of tumorigenesis, immune cell activation, recruitment of immune activating or immunosuppressive cells in the tumor microenvironment (TME), and chemokine receptor expression on effector and regulatory target cells. Cancer cells engage in a complex network with their TME components via several factors including growth factors, cytokines and chemokines that are critical for the growth of primary tumor and metastasis. However, chemokines show a multifaceted role in tumor progression including maintenance of stem-like properties, tumor cell proliferation/survival/senescence, angiogenesis, and metastasis. The heterogeneity of solid tumors in primary and metastatic cancers presents a challenge to the development of successful cancer therapy. Despite extensive research on how solid tumors escape immune cell-mediated anti-tumor response, finding an effective therapy for metastatic cancer still remains a challenge. This review discusses the multifarious roles of chemokines in solid tumors including various chemokine signaling pathways such as CXCL8-CXCR1/2, CXCL9, 10, 11-CXCR3, CXCR4-CXCL12, CCL(X)-CCR(X) in primary and metastatic cancers. We further discuss the novel therapeutic approaches that have been developed by major breakthroughs in chemokine research to treat cancer patients by the strategic blockade/activation of these signaling axes alone or in combination with immunotherapies.


Assuntos
Neoplasias , Humanos , Neoplasias/patologia , Microambiente Tumoral , Neovascularização Patológica , Imunoterapia , Biologia
4.
Phytother Res ; 37(10): 4819-4837, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37468281

RESUMO

Combining anti-cancer drugs has been exploited as promising treatment strategy to target lung cancer. Synergistic chemotherapies increase anti-cancer effect and reduce effective drug doses and side effects. In this study, therapeutic potential of escin in combination with sorafenib has been explored. 3-(4,5-Dimethylthiazol-2-yl)-2 5-diphenyltetrazolium bromide assay was used to calculate IC50 values. The synergy was evaluated using Chou-Talaly algorithm. Cellular reactive oxygen species, mitochondrial membrane potential, annexin V, and cell-cycle studies were done by flow-cytometer, and autophagy biomarkers expression were determined using western blotting. Moreover, autophagy was knocked down using ATG5 siRNA to confirm its role, diethylnitrosamine-induced lung cancer model was used to check the synergy of sorafenib/escin. Escin significantly reduced the IC50 of sorafenib in A549 and NCIH460 cells. The combination of sorafenib/escin produced a 2.95 and 5.45 dose reduction index for sorafenib in A549 and NCI-H460 cells. The combination of over-expressed p62 and LC3-II reflects autophagy block-mediated late apoptosis. This phenomenon was reconfirmed by ATG5 knockdown. This combination also selectively targeted G0/G1 phase of cancer cells. In in vivo study, the combination reduced tumour load and lower elevated serum biochemical parameters. The combination of sorafenib/escin synergistically inhibits autophagy to induce late apoptosis in lung cancer cells' G0/G1 phase.

5.
J Hepatol ; 77(5): 1246-1255, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35820507

RESUMO

BACKGROUND & AIMS: Several recent clinical studies have shown that serum homocysteine (Hcy) levels are positively correlated, while vitamin B12 (B12) and folate levels are negative correlated, with non-alcoholic steatohepatitis (NASH) severity. However, it is not known whether hyperhomocysteinemia (HHcy) plays a pathogenic role in NASH. METHODS: We examined the effects of HHcy on NASH progression, metabolism, and autophagy in dietary and genetic mouse models, patients, and primates. We employed vitamin B12 (B12) and folate (Fol) to reverse NASH features in mice and cell culture. RESULTS: Serum Hcy correlated with hepatic inflammation and fibrosis in NASH. Elevated hepatic Hcy induced and exacerbated NASH. Gene expression of hepatic Hcy-metabolizing enzymes was downregulated in NASH. Surprisingly, we found increased homocysteinylation (Hcy-lation) and ubiquitination of multiple hepatic proteins in NASH including the key autophagosome/lysosome fusion protein, Syntaxin 17 (Stx17). This protein was Hcy-lated and ubiquitinated, and its degradation led to a block in autophagy. Genetic manipulation of Stx17 revealed its critical role in regulating autophagy, inflammation and fibrosis during HHcy. Remarkably, dietary B12/Fol, which promotes enzymatic conversion of Hcy to methionine, decreased HHcy and hepatic Hcy-lated protein levels, restored Stx17 expression and autophagy, stimulated ß -oxidation of fatty acids, and improved hepatic histology in mice with pre-established NASH. CONCLUSIONS: HHcy plays a key role in the pathogenesis of NASH via Stx17 homocysteinylation. B12/folate also may represent a novel first-line therapy for NASH. LAY SUMMARY: The incidence of non-alcoholic steatohepatitis, for which there are no approved pharmacological therapies, is increasing, posing a significant healthcare challenge. Herein, based on studies in mice, primates and humans, we found that dietary supplementation with vitamin B12 and folate could have therapeutic potential for the prevention or treatment of non-alcoholic steatohepatitis.


Assuntos
Hiper-Homocisteinemia , Hepatopatia Gordurosa não Alcoólica , Animais , Ácidos Graxos , Fibrose , Ácido Fólico , Homocisteína , Humanos , Inflamação , Metionina , Camundongos , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Proteínas Qa-SNARE , Vitamina B 12 , Vitaminas
6.
Dig Dis Sci ; 67(8): 3497-3507, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-34383198

RESUMO

The liver is an organ of vital importance in the body; it is the center of metabolic activities and acts as the primary line of defense against toxic compounds. Exposure to environmental toxicants is an unavoidable fallout from rapid industrialization across the world and is even higher in developing countries. Technological development and industrialization have led to the release of toxicants such as pollutant toxic gases, chemical discharge, industrial effluents, pesticides and solvents, into the environment. In the last few years, a growing body of evidence has shed light on the potential impact of environmental toxicants on liver health, in particular, on non-alcoholic fatty liver disease (NAFLD) incidence and progression. NAFLD is a multifactorial disease linked to metabolic derangement including diabetes and other complications. Environmental toxicants including xenobiotics and pollutants may have a direct or indirect steatogenic/fibrogenic impact on the liver and should be considered as risk factors associated with NAFLD. This review discusses the contribution of environmental toxicants toward the increasing disease burden of NAFLD.


Assuntos
Hepatopatia Gordurosa não Alcoólica , Efeitos Psicossociais da Doença , Humanos , Incidência , Hepatopatia Gordurosa não Alcoólica/induzido quimicamente , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Fatores de Risco
7.
Hum Mol Genet ; 28(12): 1971-1981, 2019 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-30715350

RESUMO

Titin-truncating variants (TTNtv) are the most common genetic cause of dilated cardiomyopathy. TTNtv occur in ~1% of the general population and causes subclinical cardiac remodeling in asymptomatic carriers. In rat models with either proximal or distal TTNtv, we previously showed altered cardiac metabolism at baseline and impaired cardiac function in response to stress. However, the molecular mechanism(s) underlying these effects remains unknown. In the current study, we used rat models of TTNtv to investigate the effect of TTNtv on autophagy and mitochondrial function, which are essential for maintaining cellular metabolic homeostasis and cardiac function. In both the proximal and distal TTNtv rat models, we found increased levels of LC3B-II and p62 proteins, indicative of diminished autophagic degradation. The accumulation of autophagosomes and p62 protein in cardiomyocytes was also demonstrated by electron microscopy and immunochemistry, respectively. Impaired autophagy in the TTNtv heart was associated with increased phosphorylation of mTOR and decreased protein levels of the lysosomal protease, cathepsin B. In addition, TTNtv hearts showed mitochondrial dysfunction, as evidenced by decreased oxygen consumption rate in cardiomyocytes, increased levels of reactive oxygen species and mitochondrial protein ubiquitination. We also observed increased acetylation of mitochondrial proteins associated with decreased NAD+/NADH ratio in the TTNtv hearts. mTORC1 inhibitor, rapamycin, was able to rescue the impaired autophagy in TTNtv hearts. In summary, TTNtv leads to impaired autophagy and mitochondrial function in the heart. These changes not only provide molecular mechanisms that underlie TTNtv-associated ventricular remodeling but also offer potential targets for its intervention.


Assuntos
Autofagia/genética , Cardiomiopatia Dilatada/genética , Conectina/genética , Mitocôndrias Cardíacas/metabolismo , Miócitos Cardíacos/metabolismo , Acetilação , Animais , Autofagossomos/metabolismo , Autofagossomos/ultraestrutura , Cardiomiopatia Dilatada/metabolismo , Catepsina B/metabolismo , Células Cultivadas , Conectina/metabolismo , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Mitocôndrias Cardíacas/patologia , Proteínas Mitocondriais/metabolismo , NAD/análogos & derivados , NAD/metabolismo , Ratos , Espécies Reativas de Oxigênio/metabolismo , Deleção de Sequência , Proteína Sequestossoma-1/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Ubiquitinação
8.
Gastroenterology ; 157(3): 777-792.e14, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31078624

RESUMO

BACKGROUND & AIMS: We studied the role of interleukin 11 (IL11) signaling in the pathogenesis of nonalcoholic steatohepatitis (NASH) using hepatic stellate cells (HSCs), hepatocytes, and mouse models of NASH. METHODS: We stimulated mouse and human fibroblasts, HSCs, or hepatocytes with IL11 and other cytokines and analyzed them by imaging, immunoblot, and functional assays and enzyme-linked immunosorbent assays. Mice were given injections of IL11. Mice with disruption of the interleukin 11 receptor subunit alpha1 gene (Il11ra1-/-) mice and Il11ra1+/+ mice were fed a high-fat methionine- and choline-deficient diet (HFMCD) or a Western diet with liquid fructose (WDF) to induce steatohepatitis; control mice were fed normal chow. db/db mice were fed with methionine- and choline-deficient diet for 12 weeks and C57BL/6 NTac were fed with HFMCD for 10 weeks or WDF for 16 weeks. Some mice were given intraperitoneal injections of anti-IL11 (X203), anti-IL11RA (X209), or a control antibody at different timepoints on the diets. Livers and blood were collected; blood samples were analyzed by biochemistry and liver tissues were analyzed by histology, RNA sequencing, immunoblots, immunohistochemistry, hydroxyproline, and mass cytometry time of flight assays. RESULTS: HSCs incubated with cytokines produced IL11, resulting in activation (phosphorylation) of ERK and expression of markers of fibrosis. Livers of mice given injections of IL11 became damaged, with increased markers of fibrosis, hepatocyte cell death and inflammation. Following the HFMCD or WDF, livers from Il11ra1-/- mice had reduced steatosis, fibrosis, expression of markers of inflammation and steatohepatitis, compared to and Il11ra1+/+ mice on the same diets. Depending on the time of administration of anti-IL11 or anti-IL11RA antibodies to wild-type mice on the HFMCD or WDF, or to db/db mice on the methionine and choline-deficient diet, the antibodies prevented, stopped, or reversed development of fibrosis and steatosis. Blood samples from Il11ra1+/+ mice fed the WDF and given injections of anti-IL11 or anti-IL11RA, as well as from Il11ra1-/- mice fed WDF, had lower serum levels of lipids and glucose than mice not injected with antibody or with disruption of Il11ra1. CONCLUSIONS: Neutralizing antibodies that block IL11 signaling reduce fibrosis, steatosis, hepatocyte death, inflammation and hyperglycemia in mice with diet-induced steatohepatitis. These antibodies also improve the cardiometabolic profile of mice and might be developed for the treatment of NASH.


Assuntos
Anticorpos Neutralizantes/farmacologia , Hepatite/prevenção & controle , Subunidade alfa de Receptor de Interleucina-11/metabolismo , Interleucina-11/antagonistas & inibidores , Cirrose Hepática Experimental/prevenção & controle , Fígado/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Animais , Morte Celular/efeitos dos fármacos , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Fibroblastos/patologia , Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Células Estreladas do Fígado/patologia , Hepatite/genética , Hepatite/metabolismo , Hepatite/patologia , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Mediadores da Inflamação/metabolismo , Interleucina-11/metabolismo , Subunidade alfa de Receptor de Interleucina-11/deficiência , Subunidade alfa de Receptor de Interleucina-11/genética , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática Experimental/genética , Cirrose Hepática Experimental/metabolismo , Cirrose Hepática Experimental/patologia , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Transdução de Sinais/efeitos dos fármacos , Células THP-1
9.
Anal Chem ; 92(5): 3742-3750, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32069036

RESUMO

Cytokines are commonly measured by immunoassays; however, these have limited multiplexing capacity, are costly, and can exhibit cross-reactivity. Multiple reaction monitoring (MRM) mass spectrometry is a robust method to quantify analytes with high specificity and multiplexing ability, hence we aimed to investigate its suitability as an alternative cost-effective method for cytokine measurement. Human keratinocyte conditioned media spiked with recombinant cytokines was used as an experimental system to evaluate sensitivity, linearity, and reproducibility of an MRM assay targeting 79 peptides representing 23 human cytokines. Our MRM method was able to identify 21 cytokines by two or more unique peptides and two cytokines by a single unique peptide. In a serum-free matrix, the median LOD and LOQ for cytokine peptides was 130 and 433 pg/mL, respectively. The presence of serum increased median LOD and LOQ by about 2.3-fold. The assay shows excellent replicate consistency with 8% intra- and 12% interday coefficient of variations. We found high pH reversed-phase fractionation a useful tool to increase assay sensitivity with the drawback of increasing its variability by approximately 10%. Overall, our results suggest utility of a multiplex cytokine MRM for routine measurement of secreted cytokines in cellular experiments under low serum conditions. Additional enrichment steps will be required in high complexity matrices such as serum.


Assuntos
Citocinas/metabolismo , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Meios de Cultivo Condicionados/análise , Meios de Cultivo Condicionados/metabolismo , Citocinas/química , Humanos , Concentração de Íons de Hidrogênio , Queratinócitos/citologia , Queratinócitos/metabolismo , Limite de Detecção , Peptídeos/análise , Cultura Primária de Células , Reprodutibilidade dos Testes
10.
Biochem Biophys Res Commun ; 532(4): 570-575, 2020 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-32900486

RESUMO

Hepatocellular cancer (HCC) is one of the leading causes of mortality worldwide. Unfortunately, a limited choice of anti-cancer drugs is available for treatment, owing to their minimal efficacy and development of acquired resistance. Autophagy, a cellular survival pathway, often exhibits a pleiotropic role in HCC progression. Studies show increased autophagy in established HCC, promoting the survival of HCC cells in the tumour microenvironment. Therefore, novel anti-autophagy drugs hold promise for preventing HCC progression. Here, using a non-biased transcriptomics analysis in HepG2 cells we demonstrate the existence of an autophagy-FOXM1 nexus regulating growth in HepG2 cells. Additionally, we show that suppression of autophagy by an Unc-51 Like Autophagy Activating Kinase 1(ULK1) inhibitor not only attenuates the expression of FOXM1 and its transcriptional targets, but also has a synergistic effect on the inhibition of HepG2 growth when combined with FOXM1 inhibitors. Thus, the autophagic protein, ULK1, is a promising candidate for preventing HCC progression. Collectively, our results provide new insight into the role of autophagy in HCC growth and are a proof-of concept for combinatorial therapy using ULK1 and FOXM1 inhibitors.


Assuntos
Proteína Homóloga à Proteína-1 Relacionada à Autofagia/metabolismo , Autofagia , Carcinoma Hepatocelular/metabolismo , Proteína Forkhead Box M1/metabolismo , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Neoplasias Hepáticas/metabolismo , Autofagia/genética , Proteína Homóloga à Proteína-1 Relacionada à Autofagia/antagonistas & inibidores , Carcinoma Hepatocelular/genética , Proliferação de Células , Proteína Forkhead Box M1/antagonistas & inibidores , Inativação Gênica , Células Hep G2 , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/antagonistas & inibidores , Neoplasias Hepáticas/genética , Transdução de Sinais/efeitos dos fármacos
11.
Neurochem Res ; 45(9): 2184-2195, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32613347

RESUMO

Role of autophagy in Japanese encephalitis viral (JEV) infection is not well known. In the present study, we reported the role of autophagy flux in microglia activation, neurobehavioral function and neuronal death using a mouse model of JEV. Markers for autophagy (LC3-II/I, SQSTM1/P62, phos-Akt, phos-AMPK), and neuronal death (cleaved caspase 12, H2Ax, polyubiquitin) were investigated by western blot at 1, 3 and 7 days post inoculation. Cathepsin D was measured in cerebral cotex of JEV infected mice spectrophotometrically. Microglia activation and pro-inflammatory cytokines (IL1ß, TNF-α, IFNγ, IL6) were measured by immunohistochemistry, western blot and qPCR analysis. In order to determine the neuroinflammatory changes and autophagy mediated neuronal cell death, BV2-microglia and N2a-neuronal cells were used. Autophagy activation marker LC3-II/I and its substrate SQSTM1/P62 were significantly increased while cathepsin D activity was decreased on day 7 post inoculation in cerebral cortex. Microglia in cortex were activated and showed higher expression of proinflammatory mRNA of IL1ß, TNF-α, IFNγ and IL6, with increased DNA damage (H2AX) and neuronal cell death pathways in hippocampus and neurobehavioral dysfunction. Similar observations on JEV infection mediated autophagy flux inhibition and neuronal cell death was found in N2a neuronal cell. Collectively, our study provides evidence on the role of autophagy regulation, microglial activation and neurodegeneration following JEV infection.


Assuntos
Autofagia/fisiologia , Vírus da Encefalite Japonesa (Espécie)/patogenicidade , Encefalite Viral/fisiopatologia , Microglia/metabolismo , Animais , Apoptose/fisiologia , Encéfalo/citologia , Encéfalo/fisiopatologia , Lisossomos/metabolismo , Camundongos Endogâmicos BALB C , Neurônios/metabolismo
12.
Exp Mol Pathol ; 114: 104413, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32151561

RESUMO

Maternal inflammation ensuing from high-fat diet (HFD) intake during pregnancy is related to spontaneous preterm birth and respiratory impairment among premature infants. Recently, a circadian aligned dietary intervention referred to as Time-restricted feeding (TRF) has been reported to have beneficial metabolic effects. This study aimed to assess the effects of maternal TRF on fetal lung injury caused by maternal HFD intake. Female Wistar rats were kept on following three dietary regimens; Ad libitum normal chow diet (NCD-AL), Ad libitum HFD (HFD-AL) and Time-restricted fed HFD (HFD-TRF) from 5 months before mating and continued through pregnancy. Fetal lung samples were collected on the embryonic day 18.5, and apoptotic and inflammatory markers were assessed using TUNEL assay, western blotting, and qRT-PCR. Our results showed that TRF considerably prevented maternal HFD-induced apoptosis in fetal lung tissue that corroborated with a reduction in caspase activation and increased levels of anti-apoptotic BCL2 family proteins together with a lower level of ER-stress and autophagy markers including ATF6, CHOP and LC3-II. Besides, fetal lungs from HFD-TRF dams exhibited reduced expression of inflammatory genes that correlated with reduction and apoptotic injury throughout fetal development. Our results thus put forth TRF as a unique non-pharmacological approach to boost perinatal health beneath metabolic stress.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Inflamação/prevenção & controle , Lesão Pulmonar/prevenção & controle , Relações Materno-Fetais , Animais , Peso Corporal , Feminino , Feto/fisiopatologia , Humanos , Inflamação/etiologia , Inflamação/fisiopatologia , Pulmão/fisiopatologia , Lesão Pulmonar/etiologia , Lesão Pulmonar/fisiopatologia , Camundongos , Gravidez , Ratos , Ratos Wistar , Estresse Fisiológico/genética , Estresse Fisiológico/fisiologia
13.
Int J Mol Sci ; 21(7)2020 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-32244266

RESUMO

Peroxisome proliferator-activated receptors (PPARs) are ligand-activated transcription factors which belong to the nuclear hormone receptor superfamily. They regulate key aspects of energy metabolism within cells. Recently, PPARα has been implicated in the regulation of autophagy-lysosomal function, which plays a key role in cellular energy metabolism. PPARα transcriptionally upregulates several genes involved in the autophagy-lysosomal degradative pathway that participates in lipolysis of triglycerides within the hepatocytes. Interestingly, a reciprocal regulation of PPARα nuclear action by autophagy-lysosomal activity also exists with implications in lipid metabolism. This review succinctly discusses the unique relationship between PPARα nuclear action and lysosomal activity and explores its impact on hepatic lipid homeostasis under pathological conditions such as non-alcoholic fatty liver disease (NAFLD).


Assuntos
Lipólise/fisiologia , Fígado/metabolismo , Lisossomos/metabolismo , PPAR alfa/metabolismo , Animais , Autofagia/genética , Núcleo Celular/metabolismo , Regulação da Expressão Gênica , Hepatócitos/metabolismo , Humanos , Lisossomos/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Correpressor 1 de Receptor Nuclear/metabolismo , Coativador 1-alfa do Receptor gama Ativado por Proliferador de Peroxissomo/metabolismo , Receptores Citoplasmáticos e Nucleares/metabolismo , Triglicerídeos/metabolismo
14.
Biochem Biophys Res Commun ; 514(2): 415-421, 2019 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-31053302

RESUMO

Maternal nutrition has become a major public health concern over recent years and is a known predictor of adverse long-term metabolic derangement in offspring. Time-restricted feeding (TRF), wherein food consumption is restricted to the metabolically active phase of the day, is a dietary approach that improves metabolic parameters when consuming a high-fat diet (HFD). Here, we tested whether TRF could reduce maternal HFD associated inflammation and thereby mitigate defects in fetal organ developmental. Female rats were kept on following three dietary regimens; Ad libitum normal chow diet (NCD-AL), Ad libitum HFD (HFD-AL) and Time-restricted fed HFD (HFD-TRF) from 5 months prior to mating and continued throughout pregnancy. Rat dams were sacrificed at embryonic day 18.5 (ED18.5) and placental tissues from these rats were processed for the analysis of cellular apoptosis, inflammatory cytokines (TNFα and IL-6), oxidative stress, endoplasmic reticulum (ER) stress and autophagy. Furthermore, fetal hepatic triglyceride (TG) content and fetal lung maturation were assessed at ED18.5. Biochemical analysis revealed that HFD-TRF rat had significantly lower serum TG levels and body weight compared to HFD-AL rats. Additionally, TRF significantly blocked HFD-induced placental apoptosis and inflammation via minimizing cellular stress, and restoring autophagic flux. In addition, fetal hepatosteatosis and delayed fetal lung maturation induced by HFD was significantly ameliorated in HFD-TRF compared to HFD-AL. Collectively, our results suggest that reducing placental inflammation via TRF could prevent adverse fetal metabolic outcomes in pregnancies complicated by maternal obesity.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Jejum , Feto/efeitos dos fármacos , Feto/embriologia , Inflamação/prevenção & controle , Placenta/efeitos dos fármacos , Placenta/patologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Peso Corporal/efeitos dos fármacos , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Feminino , Humanos , Doenças Metabólicas/prevenção & controle , Obesidade/sangue , Estresse Oxidativo/efeitos dos fármacos , Gravidez , Efeitos Tardios da Exposição Pré-Natal/prevenção & controle , Triglicerídeos/sangue
15.
Biochem Biophys Res Commun ; 506(3): 597-603, 2018 11 30.
Artigo em Inglês | MEDLINE | ID: mdl-30366665

RESUMO

Hypothyroidism has been associated with better recovery from cerebral ischemia-reperfusion (IR) injury in humans. However, any therapeutic advantage of inducing hypothyroidism for mitigating IR injury without invoking the adverse effect of whole body hypothyroidism remains a challenge. We hypothesize that a deiodinase II (D2) inhibitor reverse triiodothyronine (rT3) may render brain specific hypometabolic state to ensue reduced damage during an acute phase of cerebral ischemia without affecting circulating thyroid hormone levels. Preclinical efficacy of rT3 as a neuroprotective agent was determined in rat model of middle cerebral artery occlusion (MCAO) induced cerebral IR and in oxygen glucose deprivation/reoxygenation (OGD/R) model in vitro. rT3 administration in rats significantly reduced neuronal injury markers, infarct size and neurological deficit upon ischemic insult. Similarly, rT3 increased cellular survival in primary cerebral neurons under OGD/R stress. Based on our results from both in vivo as well as in vitro models of ischemia reperfusion injury we propose rT3 as a novel therapeutic agent in reducing neuronal damage and improving stroke outcome.


Assuntos
Traumatismo por Reperfusão/tratamento farmacológico , Tri-Iodotironina Reversa/uso terapêutico , Animais , Pressão Sanguínea/efeitos dos fármacos , Células Cultivadas , Glucose/deficiência , Frequência Cardíaca/efeitos dos fármacos , Iodeto Peroxidase/metabolismo , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/patologia , Estresse Oxidativo/efeitos dos fármacos , Substâncias Protetoras/farmacologia , Substâncias Protetoras/uso terapêutico , Ratos Sprague-Dawley , Traumatismo por Reperfusão/fisiopatologia , Traumatismo por Reperfusão/prevenção & controle , Tri-Iodotironina Reversa/farmacologia
16.
Biochem Biophys Res Commun ; 502(3): 375-381, 2018 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-29852171

RESUMO

Thyroid hormones (TH) of maternal origin are crucial regulator of mammalian brain development during embryonic period. Although maternal TH deficiency during the critical periods of embryonic neo-cortical development often results in irreversible clinical outcomes, the fundamental basis of these abnormalities at a molecular level is still obscure. One of the key developmental process affected by maternal TH insufficiency is the delay in astrocyte maturation. Glial fibrillary acidic protein (Gfap) is a predominant cell marker of mature astrocyte and is regulated by TH status. Inspite, of being a TH responsive gene during neocortical development the mechanistic basis of Gfap transcriptional regulation by TH has remained elusive. In this study using rat model of maternal hypothyroidism, we provide evidence for an epigenetic silencing of Gfap under TH insufficiency and its recovery upon TH supplementation. Our results demonstrate increased DNA methylation coupled with decreased histone acetylation at the Gfap promoter leading to suppression of Gfap expression under maternal hypothyroidism. In concordance, we also observed a significant increase in histone deacetylase (HDAC) activity in neocortex of TH deficient embryos. Collectively, these results provide novel insight into the role of TH regulated epigenetic mechanisms, including DNA methylation, and histone modifications, which are critically important in mediating precise temporal neural gene regulation.


Assuntos
Epigênese Genética , Proteína Glial Fibrilar Ácida/genética , Hipotireoidismo/complicações , Hipotireoidismo/genética , Complicações na Gravidez/genética , Animais , Encéfalo/crescimento & desenvolvimento , Encéfalo/metabolismo , Metilação de DNA , Modelos Animais de Doenças , Regulação para Baixo , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Inativação Gênica , Histona Desacetilases/metabolismo , Hipotireoidismo/tratamento farmacológico , Troca Materno-Fetal/genética , Neurogênese/genética , Gravidez , Complicações na Gravidez/tratamento farmacológico , Complicações na Gravidez/metabolismo , Regiões Promotoras Genéticas , Ratos , Ratos Sprague-Dawley , Hormônios Tireóideos/administração & dosagem , Hormônios Tireóideos/deficiência
17.
Int J Mol Sci ; 19(10)2018 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-30360449

RESUMO

The thyroid hormone plays a key role in energy and nutrient metabolisms in many tissues and regulates the transcription of key genes in metabolic pathways. It has long been believed that thyroid hormones (THs) exerted their effects primarily by binding to nuclear TH receptors (THRs) that are associated with conserved thyroid hormone response elements (TREs) located on the promoters of target genes. However, recent transcriptome and ChIP-Seq studies have challenged this conventional view as discordance was observed between TH-responsive genes and THR binding to DNA. While THR association with other transcription factors bound to DNA, TH activation of THRs to mediate effects that do not involve DNA-binding, or TH binding to proteins other than THRs have been invoked as potential mechanisms to explain this discrepancy, it appears that additional novel mechanisms may enable TH to regulate the mRNA expression. These include activation of transcription factors by SIRT1 via metabolic actions by TH, the post-translational modification of THR, the THR co-regulation of transcription with other nuclear receptors and transcription factors, and the microRNA (miR) control of RNA transcript expression to encode proteins involved in the cellular metabolism. Together, these novel mechanisms enlarge and diversify the panoply of metabolic genes that can be regulated by TH.


Assuntos
Hormônios Tireóideos/metabolismo , Animais , Proteína Forkhead Box O1/genética , Proteína Forkhead Box O1/metabolismo , Humanos , Metabolismo dos Lipídeos/genética , Metabolismo dos Lipídeos/fisiologia , MicroRNAs/genética , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Receptores de Estrogênio/genética , Receptor ERRalfa Relacionado ao Estrogênio
18.
J Biol Chem ; 291(1): 198-214, 2016 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-26453307

RESUMO

MTORC2-AKT is a key regulator of carbohydrate metabolism and insulin signaling due to its effects on FOXO1 phosphorylation. Interestingly, both FOXO1 and thyroid hormone (TH) have similar effects on carbohydrate and energy metabolism as well as overlapping transcriptional regulation of many target genes. Currently, little is known about the regulation of MTORC2-AKT or FOXO1 by TH. Accordingly, we performed hepatic transcriptome profiling in mice after FOXO1 knockdown in the absence or presence of TH, and we compared these results with hepatic FOXO1 and THRB1 (TRß1) ChIP-Seq data. We identified a subset of TH-stimulated FOXO1 target genes that required co-regulation by FOXO1 and TH. TH activation of FOXO1 was directly linked to an increase in SIRT1-MTORC2 interaction and RICTOR deacetylation. This, in turn, led to decreased AKT and FOXO1 phosphorylation. Moreover, TH increased FOXO1 nuclear localization, DNA binding, and target gene transcription by reducing AKT-dependent FOXO1 phosphorylation in a THRB1-dependent manner. These events were associated with TH-mediated oxidative phosphorylation and NAD(+) production and suggested that downstream metabolic effects by TH can post-translationally activate other transcription factors. Our results showed that RICTOR/MTORC2-AKT can integrate convergent hormonal and metabolic signals to provide coordinated and sensitive regulation of hepatic FOXO1-target gene expression.


Assuntos
Proteínas de Transporte/metabolismo , Fatores de Transcrição Forkhead/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Fígado/metabolismo , Complexos Multiproteicos/metabolismo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Serina-Treonina Quinases TOR/metabolismo , Hormônios Tireóideos/farmacologia , Acetilação/efeitos dos fármacos , Animais , Núcleo Celular/efeitos dos fármacos , Núcleo Celular/metabolismo , Imunoprecipitação da Cromatina , Ativação Enzimática/efeitos dos fármacos , Proteína Forkhead Box O1 , Células Hep G2 , Humanos , Fígado/efeitos dos fármacos , Masculino , Alvo Mecanístico do Complexo 2 de Rapamicina , Camundongos Endogâmicos C57BL , NAD/metabolismo , Fosforilação/efeitos dos fármacos , Ligação Proteica/efeitos dos fármacos , Transporte Proteico/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteína Companheira de mTOR Insensível à Rapamicina , Receptores dos Hormônios Tireóideos/metabolismo , Sirtuína 1/metabolismo , Regulação para Cima/efeitos dos fármacos
19.
Clin Infect Dis ; 64(7): 852-859, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-28034886

RESUMO

BACKGROUND: The duration of antibody response following reduced human papillomavirus (HPV) vaccine doses has not been determined. We compared the antibody responses in girls previously vaccinated with zero, 1, 2, or 3 doses of quadrivalent HPV vaccine (4vHPV; Gardasil, Merck) 6 years previously. METHODS: A prospective cohort study was undertaken in 200 Fijian girls 15-19 years of age. Approximately equal numbers of girls from 2 main ethnic groups (Fijians of Indian descent [FID] and Indigenous Fijians [iTaukei]) in Fiji were recruited for each dosage groups. Blood was drawn before and 28 days following a single dose of bivalent HPV vaccine (2vHPV; Cervarix, GlaxoSmithKline). We measured neutralizing antibodies (NAb) against HPV-6, -11, -16, and -18 using the pseudovirion-based neutralization assay. RESULTS: After 6 years (before a dose of 2vHPV was given), the geometric mean NAb titers for all 4 HPV types were not statistically different between 2-dose (2D) and 3-dose (3D) recipients: HPV-6 (3D: 2216 [95% confidence interval {CI},1695-2896]; 2D: 1476 [95% CI, 1019-2137]; P = .07), HPV-11 (3D: 4431 [95% CI, 3396-5783]; 2D: 2951 [95% CI, 1984-4390]; P = .09), HPV-16 (3D: 3373 [95% CI, 2511-4530]; 2D: 3275 [95% CI, 2452-4373]; P = .89); HPV-18 (3D: 628 [95% CI: 445-888]; 2D: 606 [95% CI, 462-862]; P = .89), and were higher in FID than iTaukei girls. Although 1-dose recipients had significantly lower NAb titers than 2-/3-dose recipients, their NAb titers were 5- to 30-fold higher than unvaccinated girls. Post-2vHPV NAb titers against HPV-16 and -18 were not statistically different between girls who received 1, 2, or 3 doses of 4vHPV previously. CONCLUSIONS: Two doses of 4vHPV provide similar NAb titers as 3 doses for 6 years, although the clinical significance is unknown. A single dose of 4vHPV elicits antibodies that persisted for at least 6 years, and induced immune memory, suggesting possible protection against HPV vaccine types after a single dose of 4vHPV.


Assuntos
Anticorpos Antivirais/imunologia , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/imunologia , Papillomaviridae/imunologia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/imunologia , Adolescente , Anticorpos Neutralizantes , Anticorpos Antivirais/sangue , Criança , Relação Dose-Resposta Imunológica , Feminino , Fiji/epidemiologia , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/administração & dosagem , Humanos , Imunização Secundária , Infecções por Papillomavirus/epidemiologia , Vacinas contra Papillomavirus/administração & dosagem , Estudos Prospectivos , Fatores Socioeconômicos
20.
J Hepatol ; 67(1): 40-46, 2017 07.
Artigo em Inglês | MEDLINE | ID: mdl-28213164

RESUMO

BACKGROUND & AIMS: Carvedilol, a non-selective beta-blocker (NSBB) with additional anti-alpha 1 receptor activity, is a potent portal hypotensive agent and has been used as prophylaxis against variceal bleeding. However, its safety in patients with decompensated liver cirrhosis and ascites is still disputed. In this study, we examined whether long-term use of carvedilol in patients with ascites is a risk factor for mortality. METHODS: A single-centre retrospective analysis of 325 consecutive patients with liver cirrhosis and ascites presenting to our Liver Unit between 1st of January 2009 to 31st August 2012 was carried out. The primary outcome was all-cause and liver-specific mortality in patients receiving or not receiving carvedilol as prophylaxis against variceal bleeding. RESULTS: The final cohort after propensity score matching comprised 264 patients. Baseline ascites severity and UK end-stage liver disease (UKELD) score between carvedilol (n=132) and non-carvedilol (n=132) treated patient groups were comparable. Median follow-up time was 2.3years. Survival at the end of the follow-up was 24% and 2% for the carvedilol and the non-carvedilol groups respectively (log-rank p<0.0001). The long-term survival was significantly better in carvedilol than non-carvedilol group (log-rank p<0.001). The survival difference remained significant after adjusting for age, gender, ascites severity, aetiology of cirrhosis, previous variceal bleed, spontaneous bacterial peritonitis prophylaxis, serum albumin and UKELD with hazard ratio of 0.59 (95% confidence interval [CI]: 0.44, 0.80; p=0.001), suggesting a 41% reduction in mortality risk. When stratified by the severity of ascites, carvedilol therapy resulted in hazard ratio of 0.47 (95% CI: 0.29, 0.77; p=0.003) in those with mild ascites. Even with moderate or severe ascites, carvedilol use was not associated with increased mortality risk. CONCLUSION: Long-term carvedilol therapy is not harmful in patients with decompensated cirrhosis and ascites. LAY SUMMARY: The safety of carvedilol and other non-selective beta-blocker drugs in patients with liver cirrhosis and ascites is still debated. In this study, we have shown that carvedilol therapy in these patients was associated with reduced risk of mortality, particularly in those with mild ascites. We concluded that low dose, chronic treatment with carvedilol in patients with liver cirrhosis and ascites is not detrimental.


Assuntos
Antagonistas Adrenérgicos beta/uso terapêutico , Ascite/tratamento farmacológico , Carbazóis/uso terapêutico , Cirrose Hepática/tratamento farmacológico , Propanolaminas/uso terapêutico , Idoso , Ascite/mortalidade , Carvedilol , Causas de Morte , Feminino , Humanos , Cirrose Hepática/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
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