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1.
Proc Natl Acad Sci U S A ; 117(29): 17142-17150, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32636256

RESUMO

Gut microbes play diverse roles in modulating host fitness, including longevity; however, the molecular mechanisms underlying their mediation of longevity remain poorly understood. We performed genome-wide screens using 3,792 Escherichia coli mutants and identified 44 E. coli mutants that modulated Caenorhabditis elegans longevity. Three of these mutants modulated C. elegans longevity via the bacterial metabolite methylglyoxal (MG). Importantly, we found that low MG-producing E. coli mutants, Δhns E. coli, extended the lifespan of C. elegans through activation of the DAF-16/FOXO family transcription factor and the mitochondrial unfolded protein response (UPRmt). Interestingly, the lifespan modulation by Δhns did not require insulin/insulin-like growth factor 1 signaling (IIS) but did require TORC2/SGK-1 signaling. Transcriptome analysis revealed that Δhns E. coli activated novel class 3 DAF-16 target genes that were distinct from those regulated by IIS. Taken together, our data suggest that bacteria-derived MG modulates host longevity through regulation of the host signaling pathways rather than through nonspecific damage on biomolecules known as advanced glycation end products. Finally, we demonstrate that MG enhances the phosphorylation of hSGK1 and accelerates cellular senescence in human dermal fibroblasts, suggesting the conserved role of MG in controlling longevity across species. Together, our studies demonstrate that bacteria-derived MG is a novel therapeutic target for aging and aging-associated pathophysiology.


Assuntos
Proteínas de Caenorhabditis elegans/metabolismo , Caenorhabditis elegans , Fatores de Transcrição Forkhead/metabolismo , Longevidade/efeitos dos fármacos , Proteínas Serina-Treonina Quinases/metabolismo , Aldeído Pirúvico , Animais , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/metabolismo , Caenorhabditis elegans/microbiologia , Escherichia coli/metabolismo , Microbioma Gastrointestinal/fisiologia , Alvo Mecanístico do Complexo 2 de Rapamicina/metabolismo , Modelos Biológicos , Aldeído Pirúvico/metabolismo , Aldeído Pirúvico/farmacologia , Transdução de Sinais/efeitos dos fármacos , Transcriptoma/genética
2.
Biochem Biophys Res Commun ; 586: 157-162, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34847441

RESUMO

Sarcopenia is the age-related loss of muscle mass and function and no pharmacological medication has been approved for its treatment. We established an atrogin-1/MAFbx promoter assay to find drug candidates that inhibit myotube atrophy. Alverine citrate (AC) was identified using high-throughput screening of an existing drug library. AC is an established medicine for stomach and intestinal spasms. AC treatment increased myotube diameter and inhibited atrophy signals induced by either C26-conditioned medium or dexamethasone in cultured C2C12 myoblasts. AC also enhanced myoblast fusion through the upregulation of fusion-related genes during C2C12 myoblast differentiation. Oral administration of AC improves muscle mass and physical performance in aged mice, as well as hindlimb-disused mice. Taken together, our data suggest that AC may be a novel therapeutic candidate for improving muscle weakness, including sarcopenia.


Assuntos
Envelhecimento/genética , Diferenciação Celular/efeitos dos fármacos , Atrofia Muscular/prevenção & controle , Parassimpatolíticos/farmacologia , Propilaminas/farmacologia , Sarcopenia/prevenção & controle , Envelhecimento/metabolismo , Animais , Biomarcadores/metabolismo , Caderinas/genética , Caderinas/metabolismo , Caveolina 3/genética , Caveolina 3/metabolismo , Linhagem Celular , Dexametasona/farmacologia , Modelos Animais de Doenças , Expressão Gênica , Ensaios de Triagem em Larga Escala , Imobilização , Integrina beta1/genética , Integrina beta1/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Desenvolvimento Muscular/genética , Fibras Musculares Esqueléticas/efeitos dos fármacos , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Força Muscular/efeitos dos fármacos , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Atrofia Muscular/genética , Atrofia Muscular/metabolismo , Atrofia Muscular/patologia , Mioblastos/efeitos dos fármacos , Mioblastos/metabolismo , Mioblastos/patologia , Sarcopenia/genética , Sarcopenia/metabolismo , Sarcopenia/patologia
3.
Genes Dev ; 28(21): 2361-9, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25316675

RESUMO

Phosphorylation of peroxisome proliferator-activated receptor γ (PPARγ) at Ser273 by cyclin-dependent kinase 5 (CDK5) in adipose tissue stimulates insulin resistance, but the underlying molecular mechanisms are unclear. We show here that Thrap3 (thyroid hormone receptor-associated protein 3) can directly interact with PPARγ when it is phosphorylated at Ser273, and this interaction controls the diabetic gene programming mediated by the phosphorylation of PPARγ. Knockdown of Thrap3 restores most of the genes dysregulated by CDK5 action on PPARγ in cultured adipocytes. Importantly, reduced expression of Thrap3 in fat tissue by antisense oligonucleotides (ASOs) regulates a specific set of genes, including the key adipokines adiponectin and adipsin, and effectively improves hyperglycemia and insulin resistance in high-fat-fed mice without affecting body weight. These data indicate that Thrap3 plays a crucial role in controlling diabetic gene programming and may provide opportunities for the development of new therapeutics for obesity and type 2 diabetes.


Assuntos
Proteínas de Ligação a DNA/genética , Diabetes Mellitus Tipo 2/genética , PPAR gama/metabolismo , Fatores de Transcrição/genética , Células 3T3 , Adipocinas/genética , Animais , Células Cultivadas , Quinase 5 Dependente de Ciclina/genética , Quinase 5 Dependente de Ciclina/metabolismo , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Células HEK293 , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosforilação , Fosfosserina/metabolismo , Ligação Proteica
4.
Biochem Biophys Res Commun ; 577: 103-109, 2021 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-34509721

RESUMO

As essential phospholipid signaling regulators, phospholipase C (PLC)s are activated by various extracellular ligands and mediate intracellular signal transduction. PLCγ1 is involved in regulating various cancer cell functions. However, the precise in vivo link between PLCγ1 and cancer behavior remains undefined. To investigate the role of PLCγ1 in colorectal carcinogenesis, we generated an intestinal tissue-specific Plcg1 knock out (KO) in adenomatous polyposis coli (Apc) Min/+ mice. Plcg1 deficiency in ApcMin/+ mice showed earlier death, with a higher colorectal tumor incidence in both number and size than in wild-type mice. Mechanistically, inhibition of PLCγ1 increased the levels of its substrate phosphoinositol 4,5-bisphosphate (PIP2) at the plasma membrane and promoted the activation of Wnt receptor low-density lipoprotein receptor-related protein 6 (LRP6) by glycogen synthase kinase 3ß (GSK3ß) to enhance ß-catenin signaling. Enhanced cell proliferation and Wnt/ß-catenin signaling were observed in colon tumors from Plcg1 KO mice. Furthermore, low PLCγ1 expression was associated with a poor prognosis of colon cancer patients. Collectively, we demonstrated the role of PLCγ1 in vivo as a tumor suppressor relationship between the regulation of the PIP2 level and Wnt/ß-catenin-dependent intestinal tumor formation.


Assuntos
Proliferação de Células/genética , Neoplasias Colorretais/genética , Regulação Neoplásica da Expressão Gênica , Fosfolipase C gama/genética , Via de Sinalização Wnt/genética , beta Catenina/genética , Animais , Linhagem Celular Tumoral , Neoplasias Colorretais/enzimologia , Neoplasias Colorretais/patologia , Progressão da Doença , Glicogênio Sintase Quinase 3 beta/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Humanos , Intestinos/enzimologia , Intestinos/patologia , Estimativa de Kaplan-Meier , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/genética , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfatidilinositol 4,5-Difosfato/metabolismo , Fosfolipase C gama/deficiência , beta Catenina/metabolismo
5.
Brain ; 143(12): 3699-3716, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-33300544

RESUMO

The dopamine system in the midbrain is essential for volitional movement, action selection, and reward-related learning. Despite its versatile roles, it contains only a small set of neurons in the brainstem. These dopamine neurons are especially susceptible to Parkinson's disease and prematurely degenerate in the course of disease progression, while the discovery of new therapeutic interventions has been disappointingly unsuccessful. Here, we show that O-GlcNAcylation, an essential post-translational modification in various types of cells, is critical for the physiological function and survival of dopamine neurons. Bidirectional modulation of O-GlcNAcylation importantly regulates dopamine neurons at the molecular, synaptic, cellular, and behavioural levels. Remarkably, genetic and pharmacological upregulation of O-GlcNAcylation mitigates neurodegeneration, synaptic impairments, and motor deficits in an animal model of Parkinson's disease. These findings provide insights into the functional importance of O-GlcNAcylation in the dopamine system, which may be utilized to protect dopamine neurons against Parkinson's disease pathology.


Assuntos
Acetilglucosamina/metabolismo , Neurônios Dopaminérgicos/patologia , Doença de Parkinson/patologia , Animais , Comportamento Animal , Sobrevivência Celular , Fenômenos Eletrofisiológicos , Feminino , Imuno-Histoquímica , Masculino , Camundongos , Transtornos dos Movimentos/etiologia , Transtornos dos Movimentos/prevenção & controle , Doenças Neurodegenerativas/prevenção & controle , Optogenética , Doença de Parkinson/psicologia , Modificação Traducional de Proteínas , Sinapses/patologia , Regulação para Cima/efeitos dos fármacos
6.
FASEB J ; 33(10): 10668-10679, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31268747

RESUMO

PLC-ß exerts biologic influences through GPCR. GPCRs are involved in regulating glucose-stimulated insulin secretion (GSIS). Previous studies have suggested that PLC-ßs might play an important role in pancreatic ß cells. However, because of a lack of the specific inhibitors of PLC-ß isozymes and appropriate genetic models, the in vivo function of specific PLC-ß isozymes in pancreatic ß cells and their physiologic relevance in the regulation of insulin secretion have not been studied so far. The present study showed that PLC-ß1 was crucial for ß-cell function by generation of each PLC-ß conditional knockout mouse. Mice lacking PLC-ß1 in ß cells exhibited a marked defect in GSIS, leading to glucose intolerance. In ex vivo studies, the secreted insulin level and Ca2+ response in Plcb1f/f; pancreas/duodenum homeobox protein 1 (Pdx1)-Cre recombinase-estrogen receptor T2 (CreERt2) islets was lower than those in the Plcb1f/f islets under the high-glucose condition. PLC-ß1 led to potentiate insulin secretion via stimulation of particular Gq-protein-coupled receptors. Plcb1f/f; Pdx1-CreERt2 mice fed a high-fat diet developed more severe glucose intolerance because of a defect in insulin secretion. The present study identified PLC-ß1 as an important molecule that regulates ß cell insulin secretion and can be considered a candidate for therapeutic intervention in diabetes mellitus.-Hwang, H.-J., Yang, Y. R., Kim, H. Y., Choi, Y., Park, K.-S., Lee, H., Ma, J. S., Yamamoto, M., Kim, J., Chae, Y. C., Choi, J. H., Cocco, L., Berggren, P.-O., Jang, H.-J., Suh, P.-G. Phospholipase Cß1 potentiates glucose-stimulated insulin secretion.


Assuntos
Glucose/metabolismo , Secreção de Insulina/fisiologia , Fosfolipase C beta/metabolismo , Animais , Linhagem Celular , Dieta Hiperlipídica/efeitos adversos , Intolerância à Glucose/genética , Intolerância à Glucose/metabolismo , Intolerância à Glucose/patologia , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Técnicas In Vitro , Secreção de Insulina/genética , Células Secretoras de Insulina/metabolismo , Células Secretoras de Insulina/patologia , Ilhotas Pancreáticas/metabolismo , Ilhotas Pancreáticas/patologia , Isoenzimas/deficiência , Isoenzimas/genética , Isoenzimas/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfolipase C beta/deficiência , Fosfolipase C beta/genética , Receptores Acoplados a Proteínas G/metabolismo , Transativadores/genética , Transativadores/metabolismo
7.
EMBO Rep ; 19(11)2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30224412

RESUMO

Coordinated expression of guidance molecules and their signal transduction are critical for correct brain wiring. Previous studies have shown that phospholipase C gamma1 (PLCγ1), a signal transducer of receptor tyrosine kinases, plays a specific role in the regulation of neuronal cell morphology and motility in vitro However, several questions remain regarding the extracellular stimulus that triggers PLCγ1 signaling and the exact role PLCγ1 plays in nervous system development. Here, we demonstrate that PLCγ1 mediates axonal guidance through a netrin-1/deleted in colorectal cancer (DCC) complex. Netrin-1/DCC activates PLCγ1 through Src kinase to induce actin cytoskeleton rearrangement. Neuronal progenitor-specific knockout of Plcg1 in mice causes axon guidance defects in the dorsal part of the mesencephalon during embryogenesis. Adult Plcg1-deficient mice exhibit structural alterations in the corpus callosum, substantia innominata, and olfactory tubercle. These results suggest that PLCγ1 plays an important role in the correct development of white matter structure by mediating netrin-1/DCC signaling.


Assuntos
Axônios/fisiologia , Encéfalo/embriologia , Netrina-1/metabolismo , Fosfolipase C gama/metabolismo , Animais , Axônios/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Receptor DCC/metabolismo , Feminino , Masculino , Mesencéfalo/embriologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Netrina-1/genética , Fosfolipase C gama/genética , Fosforilação , Gravidez , Quinases da Família src/metabolismo
9.
Diabetologia ; 58(12): 2867-76, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26342595

RESUMO

AIMS/HYPOTHESIS: O-GlcNAcylation plays a role as a metabolic sensor regulating cellular signalling, transcription and metabolism. Transcription factors and signalling pathways related to metabolism are modulated by N-acetyl-glucosamine (O-GlcNAc) modification. Aberrant regulation of O-GlcNAcylation is closely linked to insulin resistance, type 2 diabetes and obesity. Current evidence shows that increased O-GlcNAcylation negatively regulates insulin signalling, which is associated with insulin resistance and type 2 diabetes. Here, we aimed to evaluate the effects of Oga (also known as Mgea5) haploinsufficiency, which causes hyper-O-GlcNAcylation, on metabolism. METHODS: We examined whether Oga(+/-) mice developed insulin resistance. Metabolic variables were determined including body weight, glucose and insulin tolerance, metabolic rate and thermogenesis. RESULTS: Oga deficiency does not affect insulin signalling even at hyper-O-GlcNAc levels. Oga(+/-) mice are lean with reduced fat mass and improved glucose tolerance. Furthermore, Oga(+/-) mice resist high-fat diet-induced obesity with ameliorated hepatic steatosis and improved glucose metabolism. Oga haploinsufficiency potentiates energy expenditure through the enhancement of brown adipocyte differentiation from the stromal vascular fraction of subcutaneous white adipose tissue (WAT). CONCLUSIONS/INTERPRETATION: Our observations suggest that O-GlcNAcase (OGA) is essential for energy metabolism via regulation of the thermogenic WAT program.


Assuntos
Tecido Adiposo Marrom/metabolismo , Tecido Adiposo Branco/metabolismo , Metabolismo Energético/genética , Obesidade/genética , beta-N-Acetil-Hexosaminidases/genética , Acetilglucosamina/metabolismo , Adipócitos Marrons/metabolismo , Adipócitos Marrons/patologia , Animais , Glicemia/metabolismo , Peso Corporal/genética , Diferenciação Celular , Diabetes Mellitus Tipo 2/genética , Intolerância à Glucose/genética , Resistência à Insulina/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Transdução de Sinais , Termogênese/genética
10.
J Biol Chem ; 289(38): 26618-26629, 2014 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-25100724

RESUMO

Thiazolidinedione class of anti-diabetic drugs which are known as peroxisome proliferator-activated receptor γ (PPARγ) ligands have been used to treat metabolic disorders, but thiazolidinediones can also cause several severe side effects, including congestive heart failure, fluid retention, and weight gain. In this study, we describe a novel synthetic PPARγ ligand UNIST HYUNDAI Compound 1 (UHC1) that binds tightly to PPARγ without the classical agonism and which blocks cyclin-dependent kinase 5 (CDK5)-mediated PPARγ phosphorylation. We modified the non-agonist PPARγ ligand SR1664 chemically to improve its solubility and then developed a novel PPARγ ligand, UHC1. According to our docking simulation, UHC1 occupied the ligand-binding site of PPARγ with a higher docking score than SR1664. In addition, UHC1 more potently blocked CDK5-mediated PPARγ phosphorylation at Ser-273. Surprisingly, UHC1 treatment effectively ameliorated the inflammatory response both in vitro and in high-fat diet-fed mice. Furthermore, UHC1 treatment dramatically improved insulin sensitivity in high-fat diet-fed mice without causing fluid retention and weight gain. Taken together, compared with SR1664, UHC1 exhibited greater beneficial effects on glucose and lipid metabolism by blocking CDK5-mediated PPARγ phosphorylation, and these data indicate that UHC1 could be a novel therapeutic agent for use in type 2 diabetes and related metabolic disorders.


Assuntos
Benzoatos/farmacologia , Quinase 5 Dependente de Ciclina/fisiologia , Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Indóis/farmacologia , PPAR gama/metabolismo , Células 3T3-L1 , Adipogenia/efeitos dos fármacos , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Benzoatos/química , Sítios de Ligação , Compostos de Bifenilo/química , Compostos de Bifenilo/farmacologia , Avaliação Pré-Clínica de Medicamentos , Células HEK293 , Humanos , Ligação de Hidrogênio , Hipoglicemiantes/química , Indóis/química , Mediadores da Inflamação/metabolismo , Resistência à Insulina , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , PPAR gama/agonistas , PPAR gama/química , Fosforilação , Ligação Proteica , Processamento de Proteína Pós-Traducional , Ratos Sprague-Dawley
11.
Arterioscler Thromb Vasc Biol ; 34(8): 1697-703, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24947526

RESUMO

OBJECTIVE: Aberrant regulation of the proliferation, survival, and migration of endothelial cells (ECs) is closely related to the abnormal angiogenesis that occurs in hypoxia-induced pathological situations, such as cancer and vascular retinopathy. Hypoxic conditions and the subsequent upregulation of hypoxia-inducible factor-1α and target genes are important for the angiogenic functions of ECs. Phospholipase D2 (PLD2) is a crucial signaling mediator that stimulates the production of the second messenger phosphatidic acid. PLD2 is involved in various cellular functions; however, its specific roles in ECs under hypoxia and in vivo angiogenesis remain unclear. In the present study, we investigated the potential roles of PLD2 in ECs under hypoxia and in hypoxia-induced pathological angiogenesis in vivo. APPROACH AND RESULTS: Pld2 knockout ECs exhibited decreased hypoxia-induced cellular responses in survival, migration, and thus vessel sprouting. Analysis of hypoxia-induced gene expression revealed that PLD2 deficiency disrupted the upregulation of hypoxia-inducible factor-1α target genes, including VEGF, PFKFB3, HMOX-1, and NTRK2. Consistent with this, PLD2 contributed to hypoxia-induced hypoxia-inducible factor-1α expression at the translational level. The roles of PLD2 in hypoxia-induced in vivo pathological angiogenesis were assessed using oxygen-induced retinopathy and tumor implantation models in endothelial-specific Pld2 knockout mice. Pld2 endothelial-specific knockout retinae showed decreased neovascular tuft formation, despite a larger avascular region. Tumor growth and tumor blood vessel formation were also reduced in Pld2 endothelial-specific knockout mice. CONCLUSIONS: Our findings demonstrate a novel role for endothelial PLD2 in the survival and migration of ECs under hypoxia via the expression of hypoxia-inducible factor-1α and in pathological retinal angiogenesis and tumor angiogenesis in vivo.


Assuntos
Carcinoma Pulmonar de Lewis/irrigação sanguínea , Células Endoteliais/enzimologia , Hipóxia/complicações , Neovascularização Patológica , Fosfolipase D/deficiência , Neovascularização Retiniana/enzimologia , Vasos Retinianos/enzimologia , Animais , Animais Recém-Nascidos , Hipóxia Celular , Movimento Celular , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Modelos Animais de Doenças , Células Endoteliais/patologia , Regulação da Expressão Gênica , Células Endoteliais da Veia Umbilical Humana/enzimologia , Células Endoteliais da Veia Umbilical Humana/patologia , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fosfolipase D/genética , Interferência de RNA , Neovascularização Retiniana/etiologia , Neovascularização Retiniana/genética , Neovascularização Retiniana/patologia , Vasos Retinianos/patologia , Fatores de Tempo , Técnicas de Cultura de Tecidos , Transfecção
12.
Proc Natl Acad Sci U S A ; 109(32): 13094-9, 2012 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-22826223

RESUMO

Voluntary exercise is known to have an antidepressant effect. However, the underlying mechanism for this antidepressant action of exercise remains unclear, and little progress has been made in identifying genes that are directly involved. We have identified macrophage migration inhibitory factor (MIF) by analyzing existing mRNA microarray data and confirmed the augmented expression of selected genes under two experimental conditions: voluntary exercise and electroconvulsive seizure. A proinflammatory cytokine, MIF is expressed in the central nervous system and involved in innate and adaptive immune responses. A recent study reported that MIF is involved in antidepressant-induced hippocampal neurogenesis, but the mechanism remains elusive. In our data, tryptophan hydroxylase 2 (Tph2) and brain-derived neurotrophic factor (Bdnf) expression were induced after MIF treatment in vitro, as well as during both exercise and electroconvulsive seizure in vivo. This increment of Tph2 was accompanied by increases in the levels of total serotonin in vitro. Moreover, the MIF receptor CD74 and the ERK1/2 pathway mediate the MIF-induced Tph2 and Bdnf gene expression as well as serotonin content. Experiments in Mif(-/-) mice revealed depression-like behaviors and a blunted antidepressant effect of exercise, as reflected by changes in Tph2 and Bdnf expression in the forced swim test. In addition, administration of recombinant MIF protein produced antidepressant-like behavior in rats in the forced swim test. Taken together, these results suggest a role of MIF in mediating the antidepressant action of exercise, probably by enhancing serotonin neurotransmission and neurotrophic factor-induced neurogenesis in the brain.


Assuntos
Depressão/terapia , Eletrochoque/métodos , Oxirredutases Intramoleculares/farmacologia , Fatores Inibidores da Migração de Macrófagos/farmacologia , Atividade Motora/fisiologia , Análise de Variância , Animais , Western Blotting , Fator Neurotrófico Derivado do Encéfalo/metabolismo , Células Cultivadas , Primers do DNA/genética , Imuno-Histoquímica , Infusões Intraventriculares , Oxirredutases Intramoleculares/administração & dosagem , Oxirredutases Intramoleculares/genética , Fatores Inibidores da Migração de Macrófagos/administração & dosagem , Fatores Inibidores da Migração de Macrófagos/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Atividade Motora/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Recombinantes/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serotonina/metabolismo , Triptofano Hidroxilase/metabolismo
13.
Exp Mol Med ; 56(7): 1620-1630, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38945956

RESUMO

Angiotensin II (AngII) induces the contraction and proliferation of vascular smooth muscle cells (VSMCs). AngII activates phospholipase C-ß (PLC-ß), thereby inducing Ca2+ mobilization as well as the production of reactive oxygen species (ROS). Since contraction is a unique property of contractile VSMCs, signaling cascades related to the proliferation of VSMCs may differ. However, the specific molecular mechanism that controls the contraction or proliferation of VSMCs remains unclear. AngII-induced ROS production, migration, and proliferation were suppressed by inhibiting PLC-ß3, inositol trisphosphate (IP3) receptor, and NOX or by silencing PLC-ß3 or NOX1 but not by NOX4. However, pharmacological inhibition or silencing of PLC-ß3 or NOX did not affect AngII-induced VSMC contraction. Furthermore, the AngII-dependent constriction of mesenteric arteries isolated from PLC-ß3∆SMC, NOX1-/-, NOX4-/- and normal control mice was similar. AngII-induced VSMC contraction and mesenteric artery constriction were blocked by inhibiting the L-type calcium channel Rho-associated kinase 2 (ROCK2) or myosin light chain kinase (MLCK). The activation of ROCK2 and MLCK was significantly induced in PLC-ß3∆SMC mice, whereas the depletion of Ca2+ in the extracellular medium suppressed the AngII-induced activation of ROCK2, MLCK, and vasoconstriction. AngII-induced hypertension was significantly induced in NOX1-/- and PLC-ß3∆SMC mice, whereas LCCA ligation-induced neointima formation was significantly suppressed in NOX1-/- and PLC-ß3∆SMC mice. These results suggest that PLC-ß3 is essential for vascular hyperplasia through NOX1-mediated ROS production but is nonessential for vascular constriction or blood pressure regulation.


Assuntos
Angiotensina II , Hiperplasia , Músculo Liso Vascular , Fosfolipase C beta , Espécies Reativas de Oxigênio , Vasoconstrição , Animais , Masculino , Camundongos , Angiotensina II/metabolismo , Proliferação de Células , Camundongos Knockout , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Fosfolipase C beta/metabolismo , Fosfolipase C beta/genética , Espécies Reativas de Oxigênio/metabolismo , Quinases Associadas a rho/metabolismo , Quinases Associadas a rho/genética
14.
Nat Cell Biol ; 8(12): 1389-97, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17128263

RESUMO

Growth hormone binds to its membrane receptor (GHR), whereby it regulates many cellular functions, including proliferation, differentiation and chemotaxis. However, although the activation of growth hormone-mediated signalling is well understood, the precise mechanism responsible for its regulation has not been elucidated. Here, we demonstrate that phospholipase Cgamma1 (PLCgamma1) modulates the action of growth hormone-mediated signalling by interacting with tyrosine kinase Jak2 (janus kinase 2) in a growth hormone-dependent manner. In the absence of PLCgamma1 (PLCgamma1(-/-)), growth hormone-induced JAK2 and STAT5 phosphorylation significantly increased in mouse embryonic fibroblasts (MEFs). Furthermore, the re-expression of PLCgamma1 reduced growth hormone-induced Jak2 activation. Growth hormone-induced Jak2 phosphorylation was enhanced by siRNA-specific knockdown of PLCgamma1. Interestingly, PLCgamma1 physically linked Jak2 and protein tyrosine phosphatase-1B (PTP-1B) by binding to both using different domains, and this process was implicated in the modulation of cytokine signalling through Jak2. In addition, in PLCgamma1(-/-) MEFs, growth hormone-dependent c-Fos activation was upregulated and growth hormone-induced proliferation was potentiated. These results suggest that PLCgamma1 has a key function in the regulation of growth hormone-mediated signalling by negatively regulating Jak2 activation.


Assuntos
Regulação para Baixo/efeitos dos fármacos , Hormônio do Crescimento/farmacologia , Janus Quinase 2/metabolismo , Fosfolipase C gama/metabolismo , Proteínas Tirosina Fosfatases/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Proliferação de Células/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Humanos , Camundongos , Células NIH 3T3 , Fosfolipase C gama/deficiência , Ligação Proteica/efeitos dos fármacos , Proteína Tirosina Fosfatase não Receptora Tipo 1 , Proteínas Recombinantes de Fusão/metabolismo , Fator de Transcrição STAT5/metabolismo , Ativação Transcricional/efeitos dos fármacos
15.
Aging (Albany NY) ; 15(11): 4667-4684, 2023 06 12.
Artigo em Inglês | MEDLINE | ID: mdl-37310402

RESUMO

Exercise and caloric restriction (CR) significantly increase longevity across a range of species and delay aging-related losses in organ function. Although both interventions enhance skeletal muscle function, the molecular mechanisms underlying these associations are unknown. We sought to identify genes regulated by CR and exercise in muscle, and investigate their relationship with muscle function. To do this, expression profiles of Gene Expression Omnibus datasets obtained from the muscle tissue of calorie-restricted male primates and young men post-exercise were analyzed. There were seven transcripts (ADAMTS1, CPEB4, EGR2, IRS2, NR4A1, PYGO1, and ZBTB43) that were consistently upregulated by both CR and exercise training. We used C2C12 murine myoblasts to investigate the effect of silencing these genes on myogenesis, mitochondrial respiration, autophagy, and insulin signaling, all of which are processes affected by CR and exercise. Our results show that in C2C12 cells, Irs2 and Nr4a1 expression were critical for myogenesis, and five genes (Egr2, Irs2, Nr4a1, Pygo1, and ZBTB43) regulated mitochondrial respiration while having no effect on autophagy. Cpeb4 knockdown increased the expression of genes involved in muscle atrophy and induced myotube atrophy. These findings suggest new resources for studying the mechanisms underlying the beneficial effects of exercise and calorie restriction on skeletal muscle function and lifespan extension.


Assuntos
Restrição Calórica , Condicionamento Físico Animal , Masculino , Camundongos , Animais , Músculo Esquelético/metabolismo , Envelhecimento/metabolismo , Longevidade , Condicionamento Físico Animal/fisiologia , Proteínas Adaptadoras de Transdução de Sinal/metabolismo
16.
Nat Commun ; 14(1): 288, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36653384

RESUMO

Dietary restriction (DR) delays aging and the onset of age-associated diseases. However, it is yet to be determined whether and how restriction of specific nutrients promote longevity. Previous genome-wide screens isolated several Escherichia coli mutants that extended lifespan of Caenorhabditis elegans. Here, using 1H-NMR metabolite analyses and inter-species genetics, we demonstrate that E. coli mutants depleted of intracellular glucose extend C. elegans lifespans, serving as bona fide glucose-restricted (GR) diets. Unlike general DR, GR diets don't reduce the fecundity of animals, while still improving stress resistance and ameliorating neuro-degenerative pathologies of Aß42. Interestingly, AAK-2a, a new AMPK isoform, is necessary and sufficient for GR-induced longevity. AAK-2a functions exclusively in neurons to modulate GR-mediated longevity via neuropeptide signaling. Last, we find that GR/AAK-2a prolongs longevity through PAQR-2/NHR-49/Δ9 desaturases by promoting membrane fluidity in peripheral tissues. Together, our studies identify the molecular mechanisms underlying prolonged longevity by glucose specific restriction in the context of whole animals.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/metabolismo , Longevidade/genética , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas Quinases Ativadas por AMP/metabolismo , Glucose/metabolismo , Fluidez de Membrana , Escherichia coli/metabolismo , Restrição Calórica , Proteínas de Membrana/metabolismo
17.
Nat Metab ; 5(9): 1506-1525, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37653043

RESUMO

The lateral hypothalamic area (LHA) regulates food intake and energy balance. Although LHA neurons innervate adipose tissues, the identity of neurons that regulate fat is undefined. Here we show that GABRA5-positive neurons in LHA (GABRA5LHA) polysynaptically project to brown and white adipose tissues in the periphery. GABRA5LHA are a distinct subpopulation of GABAergic neurons and show decreased pacemaker firing in diet-induced obesity mouse models in males. Chemogenetic inhibition of GABRA5LHA suppresses fat thermogenesis and increases weight gain, whereas gene silencing of GABRA5 in LHA decreases weight gain. In the diet-induced obesity mouse model, GABRA5LHA are tonically inhibited by nearby reactive astrocytes releasing GABA, which is synthesized by monoamine oxidase B (Maob). Gene silencing of astrocytic Maob in LHA facilitates fat thermogenesis and reduces weight gain significantly without affecting food intake, which is recapitulated by administration of a Maob inhibitor, KDS2010. We propose that firing of GABRA5LHA suppresses fat accumulation and selective inhibition of astrocytic GABA is a molecular target for treating obesity.


Assuntos
Astrócitos , Obesidade , Masculino , Animais , Camundongos , Aumento de Peso , Neurônios , Modelos Animais de Doenças , Monoaminoxidase , Ácido gama-Aminobutírico
18.
Exp Mol Med ; 54(8): 1250-1261, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-36028759

RESUMO

Obesity is a growing global epidemic that can cause serious adverse health consequences, including insulin resistance (IR) and nonalcoholic fatty liver disease (NAFLD). Obesity development can be attributed to energy imbalance and metabolic inflexibility. Here, we demonstrated that lack of Kelch-like protein 3 (KLHL3) mitigated the development of obesity, IR, and NAFLD by increasing energy expenditure. KLHL3 mutations in humans cause Gordon's hypertension syndrome; however, the role of KLHL3 in obesity was previously unknown. We examined differences in obesity-related parameters between control and Klhl3-/- mice. A significant decrease in body weight concomitant with fat mass loss and improved IR and NAFLD were observed in Klhl3-/- mice fed a high-fat (HF) diet and aged. KLHL3 deficiency inhibited obesity, IR, and NAFLD by increasing energy expenditure with augmentation of O2 consumption and CO2 production. Delivering dominant-negative (DN) Klhl3 using adeno-associated virus into mice, thereby dominantly expressing DN-KLHL3 in the liver, ameliorated diet-induced obesity, IR, and NAFLD. Finally, adenoviral overexpression of DN-KLHL3, but not wild-type KLHL3, in hepatocytes revealed an energetic phenotype with an increase in the oxygen consumption rate. The present findings demonstrate a novel function of KLHL3 mutation in extrarenal tissues, such as the liver, and may provide a therapeutic target against obesity and obesity-related diseases.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Metabolismo Energético , Resistência à Insulina , Proteínas dos Microfilamentos , Hepatopatia Gordurosa não Alcoólica , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Dieta Hiperlipídica/efeitos adversos , Metabolismo Energético/genética , Humanos , Resistência à Insulina/genética , Fígado/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/genética , Proteínas dos Microfilamentos/metabolismo , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Obesidade/genética , Obesidade/metabolismo
19.
J Bone Metab ; 28(3): 223-230, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34520656

RESUMO

BACKGROUND: Multiple members of the transforming growth factor-ß (TGF-ß) superfamily have well-established roles in bone homeostasis. Anti-Müllerian hormone (AMH) is a member of TGF-ß superfamily of glycoproteins that is responsible for the regression of fetal Müllerian ducts and the transcription inhibition of gonadal steroidogenic enzymes. However, the involvement of AMH in bone remodeling is unknown. Therefore, we investigated whether AMH has an effect on bone cells as other TGF-ß superfamily members do. METHODS: To identify the roles of AMH in bone cells, we administered AMH during osteoblast and osteoclast differentiation, cultured the cells, and then stained the cultured cells with Alizarin red and tartrate-resistant acid phosphatase, respectively. We analyzed the expression of osteoblast- or osteoclast-related genes using real-time polymerase chain reaction and western blot. RESULTS: AMH does not affect bone morphogenetic protein 2-mediated osteoblast differentiation but inhibits receptor activator of nuclear factor-κB (NF-κB) ligand-induced osteoclast differentiation. The inhibitory effect of AMH on osteoclast differentiation is mediated by IκB-NF-κB signaling. CONCLUSIONS: AMH negatively regulates osteoclast differentiation without affecting osteoblast differentiation.

20.
Aging (Albany NY) ; 13(1): 1294-1313, 2021 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-33406502

RESUMO

Although several evidence has suggested the impact of exercise on the prevention of aging phenotypes, few studies have been conducted on the mechanism by which exercise alters the immune-cell profile, thereby improving metabolism in senile obesity. In this study, we confirmed that 4-week treadmill exercise sufficiently improved metabolic function, including increased lean mass and decreased fat mass, in 88-week-old mice. The expression level of the senescence marker p16 in the white adipose tissue (WAT) was decreased after 4-weeks of exercise. Exercise induced changes in the profiles of immune-cell subsets, including natural killer (NK) cells, central memory CD8+ T cells, eosinophils, and neutrophils, in the stromal vascular fraction of WAT. In addition, it has been shown through transcriptome analysis of WAT that exercise can activate pathways involved in the interaction between WAT and immune cells, in particular NK cells, in aged mice. These results suggest that exercise has a profound effect on changes in immune-cell distribution and senescent-cell scavenging in WAT of aged mice, eventually affecting overall energy metabolism toward a more youthful state.


Assuntos
Tecido Adiposo Branco/metabolismo , Metabolismo Energético/fisiologia , Sistema Imunitário/fisiologia , Condicionamento Físico Animal , Esforço Físico/fisiologia , Envelhecimento , Animais , Senescência Celular/fisiologia , Camundongos , Camundongos Endogâmicos C57BL , Esforço Físico/imunologia
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