RESUMO
The growth arrest and DNA damage-inducible beta (Gadd45ß) protein have been associated with various cellular functions, but its role in progressive renal disease is currently unknown. Here, we examined the effect of Gadd45ß deletion on cell proliferation and apoptosis, inflammation, and renal fibrosis in an early chronic kidney disease (CKD) mouse model following unilateral ureteral obstruction (UUO). Wild-type (WT) and Gadd45ß-knockout (KO) mice underwent either a sham operation or UUO and the kidneys were sampled eight days later. A histological assay revealed that ablation of Gadd45ß ameliorated UUO-induced renal injury. Cell proliferation was higher in Gadd45ß KO mouse kidneys, but apoptosis was similar in both genotypes after UUO. Expression of pro-inflammatory cytokines after UUO was down-regulated in the kidneys from Gadd45ß KO mice, whereas UUO-mediated immune cell infiltration remained unchanged. The expression of pro-inflammatory cytokines in response to LPS stimulation decreased in bone marrow-derived macrophages from Gadd45ß KO mice compared with that in WT mice. Importantly, UUO-induced renal fibrosis was ameliorated in Gadd45ß KO mice unlike in WT mice. Gadd45ß was involved in TGF-ß signalling pathway regulation in kidney fibroblasts. Our findings demonstrate that Gadd45ß plays a crucial role in renal injury and may be a therapeutic target for the treatment of CKD.
Assuntos
Antígenos de Diferenciação/genética , Deleção de Genes , Nefropatias/etiologia , Obstrução Ureteral/complicações , Animais , Antígenos de Diferenciação/metabolismo , Apoptose/genética , Biomarcadores , Biópsia , Linhagem Celular , Proliferação de Células , Citocinas/metabolismo , Modelos Animais de Doenças , Suscetibilidade a Doenças , Fibrose , Imuno-Histoquímica , Inflamação , Mediadores da Inflamação , Nefropatias/metabolismo , Nefropatias/patologia , Masculino , Camundongos , Camundongos Knockout , Insuficiência Renal Crônica/etiologia , Insuficiência Renal Crônica/metabolismo , Insuficiência Renal Crônica/patologia , Fator de Crescimento Transformador beta/metabolismoRESUMO
Histone acetylation is a key regulatory factor for gene expression in cells. Modulation of histone acetylation by targeting of histone acetyltransferases (HATs) effectively alters many gene expression profiles and synaptic plasticity in the brain. However, the role of HATs on L-DOPA-induced dyskinesia of Parkinson's disease (PD) has not been reported. Our aim was to determine whether HAT inhibitors such as anacardic acid, garcinol, and curcumin from natural plants reduce severity of L-DOPA-induced dyskinesia using a unilaterally 6-hydroxydopamine (6-OHDA)-lesioned PD mouse model. Anacardic acid 2 mg/kg, garcinol 5 mg/kg, or curcumin 100 mg/kg co-treatment with L-DOPA significantly reduced the axial, limb, and orofacial (ALO) score indicating less dyskinesia with administration of HAT inhibitors in 6-OHDA-lesioned mice. Additionally, L-DOPA's efficacy was not altered by the compounds in the early stage of treatment. The expression levels of c-Fos, Fra-2, and Arc were effectively decreased by administration of HAT inhibitors in the ipsilateral striatum. Our findings indicate that HAT inhibitor co-treatment with L-DOPA may have therapeutic potential for management of L-DOPA-induced dyskinesia in patients with PD.
Assuntos
Ácidos Anacárdicos/uso terapêutico , Antiparkinsonianos/toxicidade , Curcumina/uso terapêutico , Discinesia Induzida por Medicamentos/tratamento farmacológico , Inibidores Enzimáticos/uso terapêutico , Histona Acetiltransferases/antagonistas & inibidores , Levodopa/toxicidade , Transtornos Parkinsonianos/tratamento farmacológico , Terpenos/uso terapêutico , Ácidos Anacárdicos/farmacologia , Animais , Curcumina/farmacologia , Proteínas do Citoesqueleto/biossíntese , Proteínas do Citoesqueleto/genética , Avaliação Pré-Clínica de Medicamentos , Discinesia Induzida por Medicamentos/etiologia , Discinesia Induzida por Medicamentos/genética , Inibidores Enzimáticos/farmacologia , Antígeno 2 Relacionado a Fos/biossíntese , Antígeno 2 Relacionado a Fos/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Código das Histonas/efeitos dos fármacos , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/biossíntese , Proteínas do Tecido Nervoso/genética , Oxidopamina/toxicidade , Proteínas Proto-Oncogênicas c-fos/biossíntese , Proteínas Proto-Oncogênicas c-fos/genética , Organismos Livres de Patógenos Específicos , Substância Negra/efeitos dos fármacos , Substância Negra/patologia , Terpenos/farmacologiaRESUMO
Acetaminophen (APAP) overdose is a leading cause of drug-induced acute liver failure. Prolonged c-Jun N-terminal kinase (JNK) activation plays a central role in APAP-induced liver injury; however, growth arrest and DNA damage-inducible 45 beta (GADD45ß) is known to inhibit JNK phosphorylation. The orphan nuclear receptor small heterodimer partner (SHP, NR0B2) acts as a transcriptional co-repressor of various genes. The aim of the present study was to investigate the role of SHP in APAP-evoked hepatotoxicity. We used lethal (750 mg/kg) or sublethal (300 mg/kg) doses of APAP-treated wild-type (WT), Shp knockout (Shp-/-), hepatocyte-specific Shp knockout (Shphep-/-), and Shp and Gadd45ß double knockout (Shp-/-Gadd45ß-/-) mice for in vivo studies. Primary mouse hepatocytes were used for a comparative in vitro study. SHP deficiency protected against APAP toxicity with an increased survival rate, decreased liver damage, and inhibition of prolonged hepatic JNK phosphorylation in mice, which was independent of APAP metabolism regulation. Furthermore, Shphep-/- mice showed diminished APAP hepatotoxicity compared with WT mice. SHP-deficient primary mouse hepatocytes also showed decreased cell death and inhibition of sustained JNK phosphorylation following toxic APAP treatment. While SHP expression declined, GADD45ß expression increased after APAP treatment in WT mice. In Shp-/- mice, APAP-evoked GADD45ß induction was significantly enhanced. Notably, the ameliorative effects of SHP deficiency on APAP-induced liver injury were abolished in Shp-/-Gadd45ß-/- mice. The current study is the first to demonstrate that hepatocyte-specific SHP deficiency protects against APAP overdose-evoked hepatotoxicity in a JNK signaling regulation and GADD45ß dependent manner. SHP is suggested to be a novel therapeutic target for APAP overdose treatment.
Assuntos
Acetaminofen/efeitos adversos , Antígenos de Diferenciação/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Hepatócitos/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/metabolismo , Acetaminofen/farmacocinética , Animais , Antígenos de Diferenciação/genética , Hepatócitos/metabolismo , Hepatócitos/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos Knockout , Fosforilação/efeitos dos fármacos , Receptores Citoplasmáticos e Nucleares/genéticaRESUMO
When a personal exposure meter (PEM) is worn by a human subject, the electric-field strength measured at the PEM is affected by a body shadowing effect. In our study, a hybrid model is proposed for modeling the body shadowing effect for when the PEM is used in an outdoor environment. The hybrid model contains responses to direct and diffused waves, the factors related to the transmission path and cross-polarization discrimination, respectively. To derive the hybrid model, responses for the direct and diffused waves are measured using a human phantom in an anechoic chamber and a reverberation chamber, respectively. Responses are measured at multiple locations in an outdoor environment and compared to the responses of the hybrid model. The hybrid model response has quartiles that deviate by an average of only 2.2 dB (1.29) from the same quartiles of the outdoor responses. Such quartile deviations are significantly smaller than those of the previous model with a body shadowing effect. Bioelectromagnetics. 38:626-647, 2017. © 2017 Wiley Periodicals, Inc.
Assuntos
Meio Ambiente , Modelos Biológicos , Exposição à Radiação/análise , Ondas de Rádio/efeitos adversos , Radiometria/instrumentação , Difusão , Humanos , Imagens de Fantasmas , Exposição à Radiação/efeitos adversosRESUMO
The dopamine precursor 3,4-dihydroxyphenyl-l-alanine (L-DOPA) is currently the most efficacious pharmacotherapy for Parkinson's disease (PD). However, long-term L-DOPA treatment leads to the development of abnormal involuntary movements (AIMs) in patients and animal models of PD. Recently, involvement of growth arrest and DNA damage-inducible 45ß (Gadd45ß) was reported in neurological and neurobehavioral dysfunctions. However, little is known about the role of Gadd45ß in the dopaminergic nigrostriatal pathway or L-DOPA-induced dyskinesia (LID). To address this issue, we prepared an animal model of PD using unilateral 6-hydroxydopamine (6-OHDA) lesions in the substantia nigra of Gadd45ß(+/+) and Gadd45ß(-/-) mice. Dyskinetic symptoms were triggered by repetitive administration of L-DOPA in these 6-OHDA-lesioned mice. Whereas dopamine denervation in the dorsal striatum decreased Gadd45ß mRNA, chronic L-DOPA treatment significantly increased Gadd45ß mRNA expression in the 6-OHDA-lesioned striatum of wild-type mice. Using unilaterally 6-OHDA-lesioned Gadd45ß(+/+) and Gadd45ß(-/-) mice, we found that mice lacking Gadd45ß exhibited long-lasting increases in AIMs following repeated administration of L-DOPA. By contrast, adeno-associated virus-mediated expression of Gadd45ß in the striatum reduced AIMs in Gadd45ß knockout mice. The deficiency of Gadd45ß in LID increased expression of ΔFosB and c-Fos in the lesioned striatum 90 min after the last administration of L-DOPA following 11days of daily L-DOPA treatments. These data suggest that the increased expression of Gadd45ß induced by repeated administration of L-DOPA may be beneficial in patients with PD.
Assuntos
Antígenos de Diferenciação/metabolismo , Discinesia Induzida por Medicamentos/metabolismo , Levodopa/toxicidade , Transtornos Parkinsonianos/metabolismo , Animais , Antígenos de Diferenciação/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Modelos Animais de Doenças , Discinesia Induzida por Medicamentos/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Masculino , Camundongos , Camundongos Knockout , Atividade Motora/efeitos dos fármacos , Oxidopamina , Transtornos Parkinsonianos/patologia , RNA Mensageiro/metabolismo , Receptores de Dopamina D1/metabolismo , Substância Negra/metabolismo , Substância Negra/patologiaRESUMO
The dopamine precursor L-3,4-dihydroxyphenylalanine (L-DOPA) is widely used as a therapeutic choice for the treatment of patients with Parkinson's disease. However, the long-term use of L-DOPA leads to the development of debilitating involuntary movements, called L-DOPA-induced dyskinesia (LID). The cAMP/protein kinase A (PKA) signaling in the striatum is known to play a role in LID. However, from among the nine known adenylyl cyclases (ACs) present in the striatum, the AC that mediates LID remains unknown. To address this issue, we prepared an animal model with unilateral 6-hydroxydopamine lesions in the substantia nigra in wild-type and AC5-knock-out (KO) mice, and examined behavioral responses to short-term or long-term treatment with L-DOPA. Compared with the behavioral responses of wild-type mice, LID was profoundly reduced in AC5-KO mice. The behavioral protection of long-term treatment with L-DOPA in AC5-KO mice was preceded by a decrease in the phosphorylation levels of PKA substrates ERK (extracellular signal-regulated kinase) 1/2, MSK1 (mitogen- and stress-activated protein kinase 1), and histone H3, levels of which were all increased in the lesioned striatum of wild-type mice. Consistently, FosB/ΔFosB expression, which was induced by long-term L-DOPA treatment in the lesioned striatum, was also decreased in AC5-KO mice. Moreover, suppression of AC5 in the dorsal striatum with lentivirus-shRNA-AC5 was sufficient to attenuate LID, suggesting that the AC5-regulated signaling cascade in the striatum mediates LID. These results identify the AC5/cAMP system in the dorsal striatum as a therapeutic target for the treatment of LID in patients with Parkinson's disease.
Assuntos
Inibidores de Adenilil Ciclases , Antiparkinsonianos/efeitos adversos , Discinesia Induzida por Medicamentos/enzimologia , Levodopa/efeitos adversos , Transtornos Parkinsonianos/metabolismo , Adenilil Ciclases , Animais , Western Blotting , Modelos Animais de Doenças , Discinesia Induzida por Medicamentos/prevenção & controle , Imuno-Histoquímica , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
BACKGROUND & AIMS: Acetaminophen (APAP) overdose is a leading cause of drug-induced acute liver failure. Prolonged c-Jun N-terminal kinase (JNK) activation plays a central role in APAP-induced liver injury and growth arrest, and DNA damage-inducible 45 beta (Gadd45ß) is known to inhibit JNK phosphorylation. Metformin has recently been shown to have hepatoprotective effects. The aim of the present study is to investigate whether metformin mitigates APAP-induced hepatotoxicity and to ascertain the molecular basis of this effect. METHODS: We used APAP- and/or metformin-treated Gadd45ß knockout (KO) mice and wild type (WT) C57BL/6J control mice. Primary mouse hepatocytes were isolated from WT and Gadd45ß KO mice were used for in vitro study. RESULTS: Metformin pretreatment protected against APAP toxicity with decreased liver damage, and inhibited APAP-induced prolonged hepatic JNK phosphorylation in WT mice. Gadd45ß expression was increased after APAP treatment, and the expression of Gadd45ß was further enhanced by metformin. The effects of metformin on APAP-induced liver injury and JNK phosphorylation were abolished in Gadd45ß KO mice. Notably, subtoxic doses of APAP caused cell death and sustained JNK phosphorylation in Gadd45ß-deficient primary hepatocytes. In parallel, APAP increased mortality, severe liver injury, and JNK activation in Gadd45ß KO mice. Interestingly, metformin administered after APAP treatment protected against APAP-evoked hepatotoxicity in WT mice, but not in Gadd45ß KO mice. CONCLUSIONS: This study is the first to demonstrate that metformin shows protective and therapeutic effects against APAP overdose-evoked hepatotoxicity via Gadd45ß-dependent JNK regulation. Metformin would be a promising therapeutic strategy for treatment of APAP overdose.
Assuntos
Antígenos de Diferenciação/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Metformina/farmacologia , Acetaminofen/toxicidade , Animais , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/patologia , Modelos Animais de Doenças , Hepatócitos/metabolismo , Hepatócitos/patologia , Hipoglicemiantes/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais/efeitos dos fármacosRESUMO
BACKGROUND & AIMS: Nonalcoholic steatohepatitis (NASH) is associated with cirrhosis and hepatocellular carcinoma. Reactive oxygen species (ROS) and reactive nitrogen species (RNS) play key roles in the development of the disease. However, the therapeutic target of NASH has not been fully defined and new treatments are needed. We investigated the protective effects of the antioxidant indole-derived NecroX-7 in a NASH mouse model using leptin-deficient ob/ob and methionine- and choline-deficient (MCD) diet-fed ob/ob mice. METHODS: Six-week-old male mice were divided into three groups: ob/+ mice, ob/ob mice treated with vehicle and ob/ob mice treated daily with NecroX-7 (20 mg/kg) for 4 weeks. To study the effects of NecroX-7 in a fibrosis model, NASH was induced by feeding ob/ob mice an MCD diet. The effects of NecroX-7 on NASH progression were evaluated using biochemical, histological and molecular markers. RESULTS: NecroX-7-treated ob/ob mice had a marked decrease in serum aspartate aminotransferase and alanine transaminase compared with vehicle-treated controls. Interestingly, hepatic steatosis and lipid peroxidation were significantly improved by NecroX-7 treatment. NecroX-7 inhibited tert-butylhydroperoxide- and H2 O2 -induced mitochondrial ROS/RNS in primary hepatocytes and attenuated mitochondrial dysfunction in vitro and in vivo. Furthermore, NecroX-7-treated mice exhibited fewer infiltrating macrophages and reduced hepatic tumour necrosis factor-alpha expression. Hepatic fibrosis in MCD-fed ob/ob mice was significantly decreased by NecroX-7 treatment. CONCLUSIONS: NecroX-7 treatment improved hepatic steatosis and fibrosis in murine NASH models. These effects occurred through the suppression of whole-cell ROS/RNS and inflammatory responses and suggest that NecroX-7 has a potential therapeutic benefit in steatohepatitis.
Assuntos
Antioxidantes/farmacologia , Inflamação/tratamento farmacológico , Fígado/efeitos dos fármacos , Mitocôndrias Hepáticas/efeitos dos fármacos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Compostos Orgânicos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Animais , Citoproteção , Metabolismo Energético/efeitos dos fármacos , Células Hep G2 , Humanos , Inflamação/metabolismo , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática Experimental/tratamento farmacológico , Cirrose Hepática Experimental/metabolismo , Cirrose Hepática Experimental/patologia , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos Obesos , Mitocôndrias Hepáticas/metabolismo , Mitocôndrias Hepáticas/patologia , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , Transdução de Sinais/efeitos dos fármacos , Fatores de TempoRESUMO
Intracellular reactive oxygen species (ROS) are essential secondary messengers in many signaling cascades governing innate immunity and cellular functions. TLR3 signaling is crucially involved in antiviral innate and inflammatory responses; however, the roles of ROS in TLR3 signaling remain largely unknown. In this study, we show that TLR3-induced ROS generation is required for the activation of NF-κB, IFN-regulatory factor 3, and STAT1-mediated innate immune responses in macrophages. TLR3 induction led to a rapid increase in ROS generation and a physical association between components of the NADPH oxidase (NOX) enzyme complex (NOX2 and p47(phox)) and TLR3 via a Ca(2+)-c-Src tyrosine kinase-dependent pathway. TLR3-induced ROS generation, NOX2, and p47(phox) were required for the phosphorylation and nuclear translocation of STAT1 and STAT2. TLR3-induced activation of STAT1 contributed to the generation of inflammatory mediators, which was significantly attenuated in NOX2- and p47(phox)-deficient macrophages, suggesting a role for ROS-STAT1 in TLR3-mediated innate immune responses. Collectively, these results provide a novel insight into the crucial role that TLR3-ROS signaling plays in innate immune responses by activating STAT1.
Assuntos
Imunidade Inata/imunologia , Espécies Reativas de Oxigênio/imunologia , Fator de Transcrição STAT1/imunologia , Transdução de Sinais/imunologia , Receptor 3 Toll-Like/imunologia , Animais , Western Blotting , Células Cultivadas , Feminino , Imunofluorescência , Imunoprecipitação , Inflamação/imunologia , Inflamação/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Confocal , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fator de Transcrição STAT1/metabolismo , Receptor 3 Toll-Like/metabolismoRESUMO
An overdose of acetaminophen (APAP) causes hepatotoxicity due to its metabolite, N-acetyl-p-benzoquinone imine. NAD(P)H: quinone oxidoreductase 1 (NQO1) is an important enzyme for detoxification, because it catabolizes endogenous/exogenous quinone to hydroquinone. Although various studies have suggested the possible involvement of NQO1 in APAP-induced hepatotoxicity, its precise role in this remains unclear. We investigated the role of NQO1 against APAP-induced hepatotoxicity using a genetically modified rodent model. NQO1 wild-type (WT) and knockout (KO) mice were treated with different doses of APAP, and we evaluated the mortality and toxicity markers for cell death caused by APAP. NQO1 KO mice showed high sensitivity to APAP-mediated hepatotoxicity (as indicated by a large necrotic region) as well as increased levels of nitrotyrosine adducts and reactive oxygen species. APAP-induced cell death in the livers and primary hepatocytes of NQO1 KO mice, which was accompanied by an extensive reduction in adenosine triphosphate (ATP) levels. In accordance with this ATP depletion, cytosolic increases in mitochondrial proteins such as apoptosis-inducing factor, second mitochondria-derived activator of caspases/DIABLO, endonuclease G, and cytochrome c, which indicate severe mitochondrial dysfunction, were observed in NQO1 KO mice but not in WT mice after APAP exposure. Severe mitochondrial depolarization was also greater in hepatocytes isolated from NQO1 KO mice. Collectively, our data suggest that NQO1 plays a critical role in protection against energy depletion caused by APAP, and NQO1 may be useful in the development of therapeutic approaches to effectively diminish the hepatotoxicity caused by an APAP overdose.
Assuntos
Acetaminofen/toxicidade , Trifosfato de Adenosina/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/etiologia , NAD(P)H Desidrogenase (Quinona)/genética , Acetaminofen/administração & dosagem , Animais , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/patologia , Relação Dose-Resposta a Droga , Hepatócitos/efeitos dos fármacos , Hepatócitos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Mitocôndrias Hepáticas/efeitos dos fármacos , Mitocôndrias Hepáticas/patologia , Espécies Reativas de Oxigênio/metabolismoRESUMO
PURPOSE: We determined whether poly(lactic-co-glycolic acid) nanoparticles would be a useful reagent for the successful monitoring of isolated islets by magnetic resonance imaging and optical imaging systems, without clinically relevant toxicity in vitro or in vivo. METHODS: We used iron oxide for MR imaging and a cyanide dye approved by the Food and Drug Administration (indocyanine green) for optical imaging and estimated the in vivo detection of transplanted pancreatic islets. RESULTS: The poly(lactic-co-glycolic acid) nanoparticles were associated with the islets in vitro and were successfully detected by 4.7 T (MR) and optical imaging, without other toxic effects. When labeled islets were transplanted under the mouse kidney capsule, in vivo T2/ T2*-weighted scans with 4.7 T MR detected as few as 300 labeled islets by 4 weeks. Optical in vivo imaging revealed indocyanine green fluorescence by 2 and 4 days after transplantation of islets containing 250 and 500 µg/mL poly(lactic-co-glycolic acid) nanoparticles, respectively. These results were further supported by the immunohistochemical results for insulin and iron in the recipient mouse kidney and pancreas. CONCLUSIONS: Taken together, these data indicate that poly(lactic-co-glycolic acid) nanoparticles may be used to label transplanted islets and may be imaged with in vivo MR and optical imaging systems.
Assuntos
Verde de Indocianina , Transplante das Ilhotas Pancreáticas/métodos , Ilhotas Pancreáticas/citologia , Ácido Láctico/química , Imageamento por Ressonância Magnética/métodos , Nanopartículas de Magnetita , Ácido Poliglicólico/química , Animais , Rastreamento de Células/métodos , Células Cultivadas , Difusão , Aumento da Imagem/métodos , Nanopartículas de Magnetita/ultraestrutura , Camundongos , Camundongos Endogâmicos C57BL , Microscopia/métodos , Nanocápsulas/química , Nanocápsulas/ultraestrutura , Copolímero de Ácido Poliláctico e Ácido Poliglicólico , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
AIMS: Primary sclerosing cholangitis (PSC) is a rare cholestatic liver disease characterized by chronic inflammation and severe fibrosis for which effective treatment options are currently lacking. In this study, we explored the potential of beta-lapachone (ßL) as a drug candidate for PSC therapy. MATERIALS AND METHODS: We employed an animal model fed a diet containing 3,5-diethoxycarbonyl-1,4-dihydrocollidine (DDC) to assess the preventive and therapeutic effects of ßL. The beneficial effects of ßL on PSC pathogenic characteristics, including blood biomarkers, inflammation, and fibrosis, were determined by assessing relevant parameters. Differential gene expression between each group was analyzed by RNA sequencing of liver tissues. Mdr2-/- mice were utilized to explore the involvement of Abcb4 in the ßL-induced improvement of PSC pathogenesis. KEY FINDINGS: ßL effectively inhibited key features of PSC pathogenesis, as demonstrated by reduced blood biomarkers and improved pathogenic characteristics. Treatment with ßL significantly mitigated DDC-induced apoptosis, cell proliferation, inflammation, and fibrosis. Analysis of differential gene expression confirmed a new insight that ßL could stimulate the expression of genes related to NAD synthesis and Abcb4. Indeed, ßL-induced NAD exhibited effective functioning, as evidenced by enhanced sirt1/3 and acetyl-lysine levels, leading to improved mitochondrial stability. The role of Abcb4 in response to ßL was confirmed in Mdr2/Abcb4 KO mice, where the beneficial effects of ßL were abolished. SIGNIFICANCE: This study provided a new concept for PSC treatment, suggesting that pharmacological stimulation of the NAD synthetic pathway and Abcb4 via ßL ameliorates PSC pathogenesis.
Assuntos
Colangite Esclerosante , Camundongos , Animais , Colangite Esclerosante/tratamento farmacológico , Colangite Esclerosante/metabolismo , Colangite Esclerosante/patologia , Roedores , NAD , Fibrose , Biomarcadores , Inflamação/tratamento farmacológico , Modelos Animais de DoençasRESUMO
Akkermansia muciniphila has received great attention because of its beneficial roles in gut health by regulating gut immunity, promoting intestinal epithelial development, and improving barrier integrity. However, A. muciniphila-derived functional molecules regulating gut health are not well understood. Microbiome-secreted proteins act as key arbitrators of host-microbiome crosstalk through interactions with host cells in the gut and are important for understanding host-microbiome relationships. Herein, we report the biological function of Amuc_1409, a previously uncharacterised A. muciniphila-secreted protein. Amuc_1409 increased intestinal stem cell (ISC) proliferation and regeneration in ex vivo intestinal organoids and in vivo models of radiation- or chemotherapeutic drug-induced intestinal injury and natural aging with male mice. Mechanistically, Amuc_1409 promoted E-cadherin/ß-catenin complex dissociation via interaction with E-cadherin, resulting in the activation of Wnt/ß-catenin signaling. Our results demonstrate that Amuc_1409 plays a crucial role in intestinal homeostasis by regulating ISC activity in an E-cadherin-dependent manner and is a promising biomolecule for improving and maintaining gut health.
Assuntos
Verrucomicrobia , beta Catenina , Masculino , Camundongos , Animais , beta Catenina/metabolismo , Verrucomicrobia/metabolismo , Intestinos , Caderinas/metabolismo , AkkermansiaRESUMO
Micelles for mucosal immunity: A mucosal vaccine system based on γ-PGA nanomicelles and viral antigens was synthesized. The intranasal administration of the vaccine system induces a high immune response both in the humoral and cellular immunity (see picture).
Assuntos
Portadores de Fármacos/administração & dosagem , Sistemas de Liberação de Medicamentos , Imunidade nas Mucosas/imunologia , Nanopartículas/administração & dosagem , Polímeros/administração & dosagem , Vacinas/administração & dosagem , Vacinas/imunologia , Administração Intranasal , Animais , Antígenos Virais/imunologia , Portadores de Fármacos/farmacocinética , Imunidade Humoral/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Muco/efeitos dos fármacos , Muco/imunologia , Ovalbumina/administração & dosagem , Ovalbumina/imunologia , Ácido Poliglutâmico/análogos & derivados , Ácido Poliglutâmico/química , Polímeros/farmacocinética , Distribuição Tecidual , VacinaçãoRESUMO
BACKGROUND: Hepatic liver disease, including primary sclerosing cholangitis (PSC), is a serious extraintestinal manifestations of colonic inflammation. Cyclic adenosine monophosphate (cAMP)-responsive element-binding protein H (CrebH) is a transcription factor expressed mostly in the liver and small intestine. However, CrebH's roles in the gut-liver axis remain unknown. METHODS: Inflammatory bowel disease (IBD) and PSC disease models were established in wild-type and CrebH-/- mice treated with dextran sulfate sodium, dinitrobenzene sulfonic acid, and diethoxycarbonyl dihydrocollidine diet, respectively. RNA sequencing were conducted to investigate differential gene expression. Exosomes were isolated from plasma and culture media. miRNA expression profiling was performed using the NanoString nCounter Mouse miRNA Panel. Effects of miR-29a-3p on adhesion molecule expression were investigated in bEnd.3 brain endothelial cells. RESULTS: CrebH-/- mice exhibited accelerated liver injury without substantial differences in the gut after administration of dextran sulfate sodium (DSS), and had similar features to PSC, including enlarged bile ducts, enhanced inflammation, and aberrant MAdCAM-1 expression. Furthermore, RNA-sequencing analysis showed that differentially expressed genes in the liver of CrebH-/- mice after DSS overlapped significantly with genes changed in PSC-liver. Analysis of plasma exosome miRNA isolated from WT and CrebH-/- mice indicates that CrebH can contribute to the exosomal miRNA profile. We also identified miR-29a-3p as an effective mediator for MAdCAM-1 expression. Administration of plasma exosome from CrebH-/- mice led to prominent inflammatory signals in the liver of WT mice with inflammatory bowel disease (IBD). CONCLUSIONS: CrebH deficiency led to increased susceptibility to IBD-induced liver diseases via enhanced expression of adhesion molecules and concomitant infiltration of T lymphocytes. Exosomes can contribute to the progression of IBD-induced liver injury in CrebH-/- mice. These study provide novel insights into the role of CrebH in IBD-induced liver injury.
RESUMO
Precise regulation of kinases and phosphatases is crucial for human metabolic homeostasis. This study aimed to investigate the roles and molecular mechanisms of protein tyrosine phosphatase type IVA1 (PTP4A1) in regulating hepatosteatosis and glucose homeostasis. Method: Ptp4a1-/- mice, adeno-associated virus encoding Ptp4a1 under liver-specific promoter, adenovirus encoding Fgf21, and primary hepatocytes were used to evaluate PTP4A1-mediated regulation in the hepatosteatosis and glucose homeostasis. Glucose tolerance test, insulin tolerance test, 2-deoxyglucose uptake assay, and hyperinsulinemic-euglycemic clamp were performed to estimate glucose homeostasis in mice. The staining, including oil red O, hematoxylin & eosin, and BODIPY, and biochemical analysis for hepatic triglycerides were performed to assess hepatic lipids. Luciferase reporter assays, immunoprecipitation, immunoblots, quantitative real-time polymerase chain reaction, and immunohistochemistry staining were conducted to explore the underlying mechanism. Results: Here, we found that deficiency of PTP4A1 aggravated glucose homeostasis and hepatosteatosis in mice fed a high-fat (HF) diet. Increased lipid accumulation in hepatocytes of Ptp4a1-/- mice reduced the level of glucose transporter 2 on the plasma membrane of hepatocytes leading to a diminution of glucose uptake. PTP4A1 prevented hepatosteatosis by activating the transcription factor cyclic adenosine monophosphate-responsive element-binding protein H (CREBH)/fibroblast growth factor 21 (FGF21) axis. Liver-specific PTP4A1 or systemic FGF21 overexpression in Ptp4a1-/- mice fed an HF diet restored the disorder of hepatosteatosis and glucose homeostasis. Finally, liver-specific PTP4A1 expression ameliorated an HF diet-induced hepatosteatosis and hyperglycemia in wild-type mice. Conclusions: Hepatic PTP4A1 is critical for regulating hepatosteatosis and glucose homeostasis by activating the CREBH/FGF21 axis. Our current study provides a novel function of PTP4A1 in metabolic disorders; hence, modulating PTP4A1 may be a potential therapeutic strategy against hepatosteatosis-related diseases.
Assuntos
Dieta Hiperlipídica , Hiperglicemia , Humanos , Animais , Camundongos , Dieta Hiperlipídica/efeitos adversos , Fígado/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/genética , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Hiperglicemia/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Glucose/metabolismo , Proteínas de Membrana/metabolismo , Proteínas de Ciclo Celular/metabolismoRESUMO
The AKT signaling pathway plays critical roles in the resolution of inflammation. However, the underlying mechanisms of anti-inflammatory regulation and signal coordination remain unclear. Here, we report that anti-inflammatory AKT signaling is coordinated by glutamyl-prolyl-tRNA synthetase 1 (EPRS1). Upon inflammatory activation, AKT specifically phosphorylates Ser999 of EPRS1 in the cytoplasmic multi-tRNA synthetase complex, inducing release of EPRS1. EPRS1 compartmentalizes AKT to early endosomes via selective binding to the endosomal membrane lipid phosphatidylinositol 3-phosphate and assembles an AKT signaling complex specific for anti-inflammatory activity. These events promote AKT activation-mediated GSK3ß phosphorylation, which increase anti-inflammatory cytokine production. EPRS1-deficient macrophages do not assemble the early endosomal complex and consequently exacerbate inflammation, decreasing the survival of EPRS1-deficient mice undergoing septic shock and ulcerative colitis. Collectively, our findings show that the housekeeping protein EPRS1 acts as a mediator of inflammatory homeostasis by coordinating compartment-specific AKT signaling.
Assuntos
Proteínas Proto-Oncogênicas c-akt , Transdução de Sinais , Camundongos , Animais , Proteínas Proto-Oncogênicas c-akt/metabolismo , Anti-Inflamatórios/farmacologia , InflamaçãoRESUMO
Abnormal proliferation and migration of vascular smooth muscle cells (VSMCs) are important pathogenic mechanisms in atherosclerosis and restenosis after vascular injury. In this study, we investigated the effects of beta-lapachone (betaL) (3,4-Dihydro-2,2-dimethyl-2H-naphtho[1,2-b]pyran-5,6-dione), which is a potent antitumor agent that stimulates NAD(P)H:quinone oxidoreductase (NQO)1 activity, on neointimal formation in animals given vascular injury and on the proliferation of VSMCs cultured in vitro. betaL significantly reduced the neointimal formation induced by balloon injury. betaL also dose-dependently inhibited the FCS- or platelet-derived growth factor-induced proliferation of VSMCs by inhibiting G(1)/S phase transition. betaL increased the phosphorylation of AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase 1 in rat and human VSMCs. Chemical inhibitors of AMPK or dominant-negative AMPK blocked the betaL-induced suppression of cell proliferation and the G(1) cell cycle arrest, in vitro and in vivo. The activation of AMPK in VSMCs by betaL is mediated by LKB1 in the presence of NQO1. Taken together, these results show that betaL inhibits VSMCs proliferation via the NQO1 and LKB1-dependent activation of AMPK. These observations provide the molecular basis that pharmacological stimulation of NQO1 activity is a new therapy for the treatment of vascular restenosis and/or atherosclerosis which are caused by proliferation of VSMCs.
Assuntos
Lesões das Artérias Carótidas/tratamento farmacológico , Estenose das Carótidas/tratamento farmacológico , Proliferação de Células/efeitos dos fármacos , Ativadores de Enzimas/farmacologia , Músculo Liso Vascular/efeitos dos fármacos , Miócitos de Músculo Liso/efeitos dos fármacos , NAD(P)H Desidrogenase (Quinona)/metabolismo , Naftoquinonas/farmacologia , Quinases Proteína-Quinases Ativadas por AMP , Proteínas Quinases Ativadas por AMP/antagonistas & inibidores , Proteínas Quinases Ativadas por AMP/metabolismo , Acetil-CoA Carboxilase/metabolismo , Animais , Lesões das Artérias Carótidas/enzimologia , Lesões das Artérias Carótidas/patologia , Estenose das Carótidas/enzimologia , Estenose das Carótidas/patologia , Ciclo Celular/efeitos dos fármacos , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Ativação Enzimática , Ativadores de Enzimas/toxicidade , Inibidores Enzimáticos/farmacologia , Células HeLa , Humanos , Hiperplasia , Masculino , Músculo Liso Vascular/enzimologia , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/enzimologia , Miócitos de Músculo Liso/patologia , NAD(P)H Desidrogenase (Quinona)/antagonistas & inibidores , NAD(P)H Desidrogenase (Quinona)/genética , Naftoquinonas/toxicidade , Fosforilação , Fator de Crescimento Derivado de Plaquetas/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Ratos , Ratos Sprague-Dawley , Proteína do Retinoblastoma/metabolismo , Prevenção Secundária , Fatores de Tempo , Proteína Supressora de Tumor p53/metabolismo , Túnica Íntima/efeitos dos fármacos , Túnica Íntima/enzimologia , Túnica Íntima/patologiaRESUMO
AIMS: The present study was carried out to investigate the antiatherosclerotic effect of antioxidant polyphenols from Phellinus baumii (PBE) in apolipoprotein E-deficient (apoE-/-) mice. METHODS AND RESULTS: apoE-/- mice were randomly divided into three groups: mice on a normal chow diet comprised the normal group, mice on an atherogenic diet plus vehicle were the control group, and mice on an atherogenic diet plus PBE (500 mg/kg) comprised the PB500 group. After 8 weeks of treatment, the plasma lipids and cytokine levels were measured. Although no significant differences were found in cholesterol levels among groups, the triglyceride level was significantly decreased in the PBE-treated group compared with the control group. Plasma tumor necrosis factor (TNF)-α and interleukin (IL)-6 levels were reduced by PBE treatment. Real-time PCR analysis of the aorta showed that PBE significantly prevented the upregulation of the vascular cell adhesion molecule (VCAM)-1, intercellular adhesion molecule (ICAM)-1, TNF-α, IL-6, and IL-1ß expression. Furthermore, reduced macrophage infiltration, lipid accumulation and atherosclerotic lesions were observed in the aortic sinus and en face of the whole aorta in PBE-fed apoE-/- mice compared with atherogenic diet-fed control mice. CONCLUSIONS: Collectively, the findings of the present study suggest that the antiatherosclerotic effect of PBE is probably related to the inhibition of adhesion molecule and cytokine expression resulting in amelioration of lesion development.