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1.
Endocrinol Metab (Seoul) ; 37(4): 620-629, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35871605

RESUMO

BACKGRUOUND: Hepatic stellate cells (HSCs) are the central players interacting with multiple cell types in liver fibrosis. The crosstalk between HSCs and macrophages has recently become clearer. Irisin, an exercise-responsive myokine, was known to have a potentially protective role in liver and renal fibrosis, especially in connection with stellate cells. This study investigated the effects of irisin on the interaction between HSCs and macrophages. METHODS: Tamm-Horsfall protein-1 (THP-1) human monocytes were differentiated into macrophages, polarized into the inflammatory M1 phenotype with lipopolysaccharide. Lieming Xu-2 (LX-2) cells, human HSCs, were treated with conditioned media (CM) from M1 macrophages, with or without recombinant irisin. HSCs responses to CM from M1 macrophages were evaluated regarding activation, proliferation, wound healing, trans-well migration, contractility, and related signaling pathway. RESULTS: CM from M1 macrophages significantly promoted HSC proliferation, wound healing, transwell migration, and contractility, but not activation of HSCs. Irisin co-treatment attenuated these responses of HSCs to CM. However, CM and irisin treatment did not induce any changes in HSC activation. Further, irisin co-treatment alleviated CM-induced increase of phopho-protein kinase B (pAKT), matrix metalloproteinase-9 (MMP-9), and tissue inhibitor of metalloproteinases-1 (TIMP-1). CONCLUSION: These findings suggested that irisin may play a protective role in the pathogenesis of liver fibrosis, especially when working in the crosstalk between HSCs and macrophages.


Assuntos
Fibronectinas , Células Estreladas do Fígado , Fibronectinas/metabolismo , Fibronectinas/farmacologia , Humanos , Cirrose Hepática/patologia , Macrófagos/metabolismo , Macrófagos/patologia
2.
Toxicol Appl Pharmacol ; 403: 115153, 2020 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-32717242

RESUMO

We investigated the vasodilatory effects of empagliflozin (a sodium-glucose co-transporter 2 inhibitor) and the underlying mechanisms using rabbit aorta. Empagliflozin induced vasodilation in a concentration-dependent manner independently of the endothelium. Likewise, pretreatment with the nitric oxide synthase inhibitor L-NAME or the SKca inhibitor apamin together with the IKca inhibitor TRAM-34 did not impact the vasodilatory effects of empagliflozin. Pretreatment with the adenylyl cyclase inhibitor SQ22536 or a guanylyl cyclase inhibitor ODQ or a protein kinase A (PKA) inhibitor KT5720 also did not alter the vasodilatory response of empagliflozin. However, the vasodilatory effects of empagliflozin were significantly reduced by pretreatment with the protein kinase G (PKG) inhibitor KT5823. Although application of the ATP-sensitive K+ (KATP) channel inhibitor glibenclamide, large-conductance Ca2+-activated K+ (BKCa) channel inhibitor paxilline, or inwardly rectifying K+ (Kir) channel inhibitor Ba2+ did not impact the vasodilatory effects of empagliflozin, pretreatment with the voltage-dependent K+ (Kv) channel inhibitor 4-AP reduced the vasodilatory effects of empagliflozin. Pretreatment with DPO-1 (Kv1.5 channel inhibitor), guangxitoxin (Kv2.1 channel inhibitor), or linopirdine (Kv7 channel inhibitor) had little effect on empagliflozin-induced vasodilation. Application of nifedipine (L-type Ca2+ channel inhibitor) or thapsigargin (sarco-endoplasmic reticulum Ca2+-ATPase pump inhibitor) did not impact empagliflozin-induced vasodilation. Therefore, empagliflozin induces vasodilation by activating PKG and Kv channels.


Assuntos
Compostos Benzidrílicos/farmacologia , Proteínas Quinases Dependentes de GMP Cíclico/metabolismo , Ativação Enzimática/efeitos dos fármacos , Glucosídeos/farmacologia , Canais de Potássio de Abertura Dependente da Tensão da Membrana/fisiologia , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Vasodilatação/efeitos dos fármacos , Adenilil Ciclases/genética , Adenilil Ciclases/metabolismo , Animais , Compostos Benzidrílicos/química , Proteínas Quinases Dependentes de AMP Cíclico/genética , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , Proteínas Quinases Dependentes de GMP Cíclico/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Glucosídeos/química , Guanilato Ciclase/genética , Guanilato Ciclase/metabolismo , Estrutura Molecular , Coelhos , Inibidores do Transportador 2 de Sódio-Glicose/química
3.
Diabetes Metab J ; 44(2): 234-244, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32347025

RESUMO

As a member of the class IIa histone deacetylases (HDACs), HDAC9 catalyzes the deacetylation of histones and transcription factors, commonly leading to the suppression of gene transcription. The activity of HDAC9 is regulated transcriptionally and post-translationally. HDAC9 is known to play an essential role in regulating myocyte and adipocyte differentiation and cardiac muscle development. Also, recent studies have suggested that HDAC9 is involved in the pathogenesis of chronic diseases, including cardiovascular diseases, osteoporosis, autoimmune disease, cancer, obesity, insulin resistance, and liver fibrosis. HDAC9 modulates the expression of genes related to the pathogenesis of chronic diseases by altering chromatin structure in their promotor region or reducing the transcriptional activity of their respective transcription factors. This review summarizes the current knowledge of the regulation of HDAC9 expression and activity. Also, the roles of HDAC9 in the pathogenesis of chronic diseases are discussed, along with potential underlying mechanisms.


Assuntos
Diabetes Mellitus/metabolismo , Histona Desacetilases/genética , Histonas/metabolismo , Proteínas Repressoras/genética , Fatores de Transcrição/metabolismo , Adipócitos/metabolismo , Adipócitos/patologia , Animais , Doenças Autoimunes/metabolismo , Doenças Autoimunes/fisiopatologia , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/fisiopatologia , Diferenciação Celular , Doença Crônica , Diabetes Mellitus/fisiopatologia , Feminino , Humanos , Resistência à Insulina/genética , Cirrose Hepática/metabolismo , Cirrose Hepática/fisiopatologia , Camundongos , Células Musculares/metabolismo , Células Musculares/patologia , Neoplasias/metabolismo , Neoplasias/fisiopatologia , Obesidade/metabolismo , Obesidade/fisiopatologia , Osteoporose/metabolismo , Osteoporose/fisiopatologia , Polimorfismo de Nucleotídeo Único/genética , Regiões Promotoras Genéticas/genética
5.
Curr Neuropharmacol ; 17(10): 990-1002, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30819085

RESUMO

Far-infrared ray (FIR) is an electromagnetic wave that produces various health benefits against pathophysiological conditions, such as diabetes mellitus, renocardiovascular disorders, stress, and depression etc. However, the therapeutic application on the FIR-mediated protective potentials remains to be further extended. To achieve better understanding on FIR-mediated therapeutic potentials, we summarized additional findings in the present study that exposure to FIR ameliorates stressful condition, memory impairments, drug dependence, and mitochondrial dysfunction in the central nervous system. In this review, we underlined that FIR requires modulations of janus kinase 2 / signal transducer and activator of transcription 3 (JAK2/STAT3), nuclear factor E2- related factor 2 (Nrf-2), muscarinic M1 acetylcholine receptor (M1 mAChR), dopamine D1 receptor, protein kinase C δ gene, and glutathione peroxidase-1 gene for exerting the protective potentials in response to neuropsychotoxic conditions.


Assuntos
Antioxidantes/uso terapêutico , Raios Infravermelhos/uso terapêutico , Doenças do Sistema Nervoso/radioterapia , Animais , Humanos , Janus Quinase 2/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Receptor Muscarínico M1/metabolismo , Receptores de Dopamina D1/metabolismo , Transdução de Sinais/fisiologia
6.
Diabetes Metab J ; 43(1): 97-104, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30302966

RESUMO

BACKGROUND: Dipeptidyl peptidase-4 (DPP-4) is strongly expressed in the kidney, and soluble levels of this protein are used as a marker in various chronic inflammatory diseases, including diabetes, coronary artery disease, and cancer. This study examined the association between the serum soluble DPP-4 levels and renal function or cardiovascular risk in patients with type 2 diabetes mellitus. METHODS: In this retrospective analysis, soluble DPP-4 levels were measured in preserved sera from 140 patients with type 2 diabetes mellitus who had participated in our previous coronary artery calcium (CAC) score study. RESULTS: The mean±standard deviation soluble DPP-4 levels in our study sample were 645±152 ng/mL. Univariate analyses revealed significant correlations of soluble DPP-4 levels with the total cholesterol (r=0.214, P=0.019) and serum creatinine levels (r=-0.315, P<0.001) and the estimated glomerular filtration rate (eGFR; estimated using the modification of diet in renal disease equation) (r=0.303, P=0.001). The associations of soluble DPP-4 levels with serum creatinine and GFR remained significant after adjusting for age, body mass index, and duration of diabetes. However, no associations were observed between soluble DPP-4 levels and the body mass index, waist circumference, or CAC score. CONCLUSION: These data suggest the potential use of serum soluble DPP-4 levels as a future biomarker of deteriorated renal function in patients with type 2 diabetes mellitus.


Assuntos
Diabetes Mellitus Tipo 2/sangue , Dipeptidil Peptidase 4/sangue , Rim/fisiopatologia , Insuficiência Renal/etiologia , Idoso , Biomarcadores/sangue , Índice de Massa Corporal , Cálcio/metabolismo , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/etiologia , Colesterol/sangue , Vasos Coronários/metabolismo , Creatinina/sangue , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Taxa de Filtração Glomerular/fisiologia , Humanos , Rim/metabolismo , Masculino , Pessoa de Meia-Idade , Insuficiência Renal/sangue , República da Coreia/epidemiologia , Estudos Retrospectivos , Medição de Risco
7.
Artigo em Inglês | MEDLINE | ID: mdl-30186230

RESUMO

The rapid increase of obesity rates worldwide is associated with chronic liver injury due to non-alcoholic fatty liver disease and non-alcoholic steatohepatitis. Chronic liver inflammation drives hepatic fibrosis, which is a highly conserved and coordinated protective response to tissue injury, and is a reversible process. Hepatocytes, immune cells, and hepatic stellate cells (HSCs) have been identified as key players in the mechanisms of hepatic fibrosis and inflammation. During the last decade, succinate, an intermediate of the tricarboxylic acid cycle in mitochondrial ATP production, has emerged as an important signaling molecule in various diseases. Succinate acts as an extracellular ligand for G-protein coupled receptor 91, also known as succinate receptor 1, which is mainly expressed in the kidney, heart, liver, immune cells, and retinal cells, suggesting a widespread function in cellular metabolism. Furthermore, succinate stabilizes hypoxia-inducible factor-1α in immune cells and tumors as a signaling molecule, and has been shown to post-translationally modify proteins. This review summarizes the recent evidence pointing to an additional role of succinate in profibrotic signaling, along with its downstream signaling pathways, and updates the current state of knowledge on the role of succinate in liver fibrosis through its action on HSCs. Further focus on this link can help identify succinate, its receptor, and its downstream signaling molecules as new targets for the treatment of liver fibrosis.

8.
J Neurosci Res ; 96(7): 1294-1310, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29476655

RESUMO

We have previously demonstrated that repeated treatment with methamphetamine (MA) results in a recognition memory impairment via upregulation of protein kinase C (PKC) δ and downregulation of the glutathione peroxidase-1 (GPx-1)-dependent antioxidant system. We also demonstrated that far-infrared ray (FIR) attenuates acute restraint stress via induction of the GPx-1 gene. Herein, we investigated whether exposure to FIR modulates MA-induced recognition memory impairment in male mice, and whether cognitive potentials mediated by FIR require modulation of the PKCδ gene, extracellular signal-regulated kinase (ERK) 1/2, and glutathione-dependent system. Repeated treatment with MA significantly increased PKCδ expression and its phosphorylation out of PKC isoenzymes (i.e., PKCα, PKCßI, PKCßII, PKCζ, and PKCδ expression) in the prefrontal cortex of mice. Exposure to FIR significantly attenuated MA-induced increase in phospho-PKCδ and decrease in phospho-ERK 1/2. In addition, FIR further facilitated the nuclear factor E2-related factor 2 (Nrf2)-dependent glutathione synthetic system. Moreover, L-buthionine-(S, R)-sulfoximine, an inhibitor of glutathione synthesis, counteracted the FIR-mediated phospho-ERK 1/2 induction and memory-enhancing activity against MA insult. More important, positive effects of FIR are comparable to those of genetic depletion of PKCδ or the antipsychotic clozapine. Our results indicate that FIR protects against MA-induced memory impairment via activations of the Nrf2-dependent glutathione synthetic system, and ERK 1/2 signaling by inhibition of the PKCδ gene.


Assuntos
Clozapina/farmacologia , Raios Infravermelhos , Memória/efeitos dos fármacos , Memória/efeitos da radiação , Metanfetamina/efeitos da radiação , Metanfetamina/toxicidade , Proteína Quinase C-delta/antagonistas & inibidores , Reconhecimento Psicológico/efeitos dos fármacos , Reconhecimento Psicológico/efeitos da radiação , Animais , Feminino , Glutationa/metabolismo , Glutationa Peroxidase/metabolismo , Masculino , Metanfetamina/química , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fator 2 Relacionado a NF-E2/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Fosforilação , Proteína Quinase C-delta/metabolismo , Proteína Quinase C-delta/efeitos da radiação , Glutationa Peroxidase GPX1
9.
Biochem Biophys Res Commun ; 495(4): 2649-2656, 2018 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-29278707

RESUMO

BACKGROUND: Chronic liver disease is becoming a major cause of morbidity and mortality worldwide. During liver injury, hepatic stellate cells (HSCs) trans-differentiate into activated myofibroblasts, which produce extracellular matrix. Succinate and succinate receptor (G-protein coupled receptor91, GPR91) signaling pathway has now emerged as a regulator of metabolic signaling. A previous study showed that succinate and its specific receptor, GPR91, are involved in the activation of HSCs and the overexpression of α-smooth muscle actin (α-SMA). Metformin, a well-known anti-diabetic drug, inhibits hepatic gluconeogenesis in the liver. Many studies have shown that metformin not only prevented, but also reversed, steatosis and inflammation in a nonalcoholic steatohepatitis (NASH) animal model. However, the role of metformin in HSC activation and succinate-GPR91 signaling has not been clarified. METHODS: The immortalized human HSCs, LX-2 cells, were used for the in vitro study. For the in vivo study, male C57BL/J6 mice were randomly divided into 3 groups and were fed with a methionine-choline-deficient diet (MCD diet group) as a nonalcoholic steatohepatitis (NASH) mouse model with or without 0.1% metformin for 12 weeks, or were fed a control methionine-choline-sufficient diet (MCS diet group). RESULTS: In our study, metformin and 5-aminoimidazole-4-carboxamide 1-ß-d-ribofuranoside (AICAR), which is an analog of adenosine monophosphate, were shown to suppress α-SMA expression via enhanced phosphorylation of AMP-activated protein kinase (AMPK) and inhibition of succinate-GPR91 signaling in activated LX-2 cells induced by palmitate- or succinate. Metformin and AICAR also reduced succinate concentration in the cell lysates when LX-2 cells were treated with palmitate. Moreover, metformin and AICAR reduced interleukin-6 and, transforming growth factor-ß1 production in succinate-treated LX-2 cells. Both metformin and AICAR inhibited succinate-stimulated HSC proliferation and cell migration. Mice fed a MCD diet demonstrated increased steatohepatitis and liver fibrosis compared to that of mice fed control diet. Metformin ameliorated steatohepatitis, liver fibrosis, inflammatory cytokine production and decreased α -SMA and GPR91expression in the livers of the MCD diet-fed mice. CONCLUSION: This study shows that metformin can attenuate activation of HSCs by activating the AMPK pathway and inhibiting the succinate-GPR91 pathway. Metformin has therapeutic potential for treating steatohepatitis and liver fibrosis.


Assuntos
Células Estreladas do Fígado/efeitos dos fármacos , Células Estreladas do Fígado/metabolismo , Cirrose Hepática/tratamento farmacológico , Cirrose Hepática/metabolismo , Metformina/administração & dosagem , Receptores Acoplados a Proteínas G/metabolismo , Ácido Succínico/metabolismo , Animais , Linhagem Celular , Relação Dose-Resposta a Droga , Regulação para Baixo/efeitos dos fármacos , Células Estreladas do Fígado/patologia , Humanos , Hipoglicemiantes/administração & dosagem , Cirrose Hepática/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Resultado do Tratamento
10.
J Reprod Immunol ; 124: 30-37, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-29049918

RESUMO

Immune tolerance at feto-maternal interfaces is a complex phenomenon. Although maternal decidual macrophages are well-known immune cells, little is known about fetal-derived macrophages (Hofbauer cells) within chorionic villi. Preeclampsia (PE) is a major cause of maternal mortality in the field of obstetrics, and the innate immunological role of maternal decidual macrophages is well known. In this study, we assessed the differential phenotypes and marker expression in fetal macrophages, known as dendritic cell-specific ICAM-grabbing non-integrin (DC-SIGN)-positive Hofbauer cells. We compared Hofbauer cell properties between normal and PE placenta chorionic villi and performed sequential staining of DC-SIGN, CD14, and CD68 to evaluate the existence of Hofbauer cells. Furthermore, to evaluate the immunological function of these cells, we stained the cells for CD163, a marker of immunoregulatory type 2 (M2) macrophages. Additionally, we examined the expression of the immunosuppressive cytokine interleukin (IL)-10, which is known to be produced by M2 macrophages. DC-SIGN+/CD14+, DC-SIGN+/CD68+, and CD163+/DC-SIGN+ cells were quantified based on photomicrographs. The results showed that CD14, CD163, DC-SIGN, and IL-10 levels were significantly downregulated in PE compared with normal. Additionally, CD163+/DC-SIGN+ Hofbauer cells were significantly less frequent in PE than in normal. DC-SIGN Hofbauer cells produced IL-10 at lower levels in the PE than in the normal. Thus, we speculate that fetal-derived Hofbauer cells may play an important role in normal pregnancy with immunosuppressive effects based on their M2 macrophage characteristics to maintain immune tolerance during pregnancy. Additionally, in PE, these functions were defective, supporting the roles of these macrophages in PE development.


Assuntos
Moléculas de Adesão Celular/metabolismo , Vilosidades Coriônicas/patologia , Histiócitos/metabolismo , Lectinas Tipo C/metabolismo , Pré-Eclâmpsia/imunologia , Receptores de Superfície Celular/metabolismo , Adulto , Antígenos CD/metabolismo , Antígenos de Diferenciação Mielomonocítica/metabolismo , Células Cultivadas , Feminino , Regulação da Expressão Gênica , Histiócitos/imunologia , Humanos , Tolerância Imunológica , Interleucina-10/metabolismo , Receptores de Lipopolissacarídeos/metabolismo , Macrófagos/imunologia , Gravidez
11.
Endocrinol Metab (Seoul) ; 32(2): 296-301, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28555465

RESUMO

Glucokinase maturity-onset diabetes of the young (GCK-MODY) represents a distinct subgroup of MODY that does not require hyperglycemia-lowering treatment and has very few diabetes-related complications. Three patients from two families who presented with clinical signs of GCK-MODY were evaluated. Whole-exome sequencing was performed and the effects of the identified mutations were assessed using bioinformatics tools, such as PolyPhen-2, SIFT, and in silico modeling. We identified two mutations: p.Leu30Pro and p.Ser383Leu. In silico analyses predicted that these mutations result in structural conformational changes, protein destabilization, and thermal instability. Our findings may inform future GCK-MODY diagnosis; furthermore, the two mutations detected in two Korean families with GCK-MODY improve our understanding of the genetic basis of the disease.

12.
Nutrients ; 9(4)2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28368304

RESUMO

There have been a limited number of studies examining the association between pre-pregnancy body mass index (BMI) and dietary inflammation during pregnancy. Our aim is to examine the association between pre-pregnancy BMI and the Dietary Inflammatory Index (DII)™ and C-reactive protein (CRP) concentrations during pregnancy. The study included 631 pregnant American women from the National Health and Nutrition Examination Survey (NHANES) cross-sectional examinations from 2003 to 2012. Pre-pregnancy BMI was calculated based on self-reported pre-pregnancy weight and measured height. The cut-offs of <18.5 (underweight), 18.5-24.9 (normal), 25.0-29.9 (overweight), and ≥30 kg/m² (obese) were used to categorize the weight status of pregnant women prior to pregnancy. The DII, a literature-based dietary index to assess the inflammatory properties of diet, was estimated based on a one-day 24-h recall. Multivariable linear and logistic regressions were performed to estimate beta coefficients and the adjusted odds ratios (AORs) and 95% confidence intervals (95% CIs) on the association of pre-pregnancy BMI categories with the DII and CRP concentrations during pregnancy. After controlling for variables including: race/ethnicity, family poverty income ratio, education, marital status, month in pregnancy, and smoking status during pregnancy; women who were obese before pregnancy (n = 136) had increased odds for being in the highest tertile of the DII and CRP concentrations compared to women with normal weight (AORs 2.40, 95% CIs 1.01-5.71; AORs 24.84, 95% CIs 6.19-99.67, respectively). These findings suggest that women with pre-pregnancy obesity had greater odds of reporting higher DII and having elevated CRP. In conclusion, high pre-pregnancy BMI was associated with increased odds of pro-inflammatory diet and elevated CRP levels during pregnancy in the USA.


Assuntos
Proteína C-Reativa/análise , Dieta/efeitos adversos , Fenômenos Fisiológicos da Nutrição Materna , Obesidade/fisiopatologia , Sobrepeso/fisiopatologia , Complicações na Gravidez/etiologia , Magreza/fisiopatologia , Adulto , Biomarcadores/sangue , Índice de Massa Corporal , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Recém-Nascido , Doenças do Recém-Nascido/sangue , Doenças do Recém-Nascido/epidemiologia , Doenças do Recém-Nascido/etiologia , Doenças do Recém-Nascido/imunologia , Masculino , Inquéritos Nutricionais , Obesidade/sangue , Obesidade/imunologia , Sobrepeso/sangue , Sobrepeso/imunologia , Gravidez , Complicações na Gravidez/sangue , Complicações na Gravidez/epidemiologia , Complicações na Gravidez/imunologia , Fatores de Risco , Autorrelato , Magreza/sangue , Magreza/imunologia , Estados Unidos/epidemiologia
13.
J Biol Chem ; 291(19): 10277-92, 2016 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-26912655

RESUMO

Sirtuin 3 (SIRT3) is an NAD(+)-dependent protein deacetylase. Recent studies have shown that SIRT3 expression is decreased in nonalcoholic fatty liver disease (NAFLD). Moreover, SIRT3 is a key regulator of succinate dehydrogenase (SDH), which catalyzes the oxidation of succinate to fumarate. Increased succinate concentrations and the specific G protein-coupled receptor 91 (GPR91) are involved in the activation of hepatic stellate cells (HSCs). In this study, we aimed to establish whether SIRT3 regulated the SDH activity, succinate, and GPR91 expression in HSCs and an animal model of NAFLD. Our goal was also to determine whether succinate released from hepatocytes regulated HSC activation. Inhibiting SIRT3 using SIRT3 siRNA exacerbated HSC activation via the SDH-succinate-GPR91 pathway, and SIRT3 overexpression or honokiol treatment attenuated HSC activation in vitro In isolated liver and HSCs from methionine- and choline-deficient (MCD) diet-induced NAFLD, the expression of SIRT3 and SDH activity was decreased, and the succinate concentrations and GPR91 expression were increased. Moreover, we found that GPR91 knockdown or resveratrol treatment improved the steatosis in MCD diet-fed mice. This investigation revealed a novel mechanism of the SIRT3-SDH-GPR91 cascade in MCD diet-induced HSC activation in NAFLD. These findings highlight the biological significance of novel strategies aimed at targeting SIRT3 and GPR91 in HSCs with the goal of improving NAFLD treatment.


Assuntos
Actinas/metabolismo , Modelos Animais de Doenças , Células Estreladas do Fígado/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Sirtuína 3/fisiologia , Succinato Desidrogenase/metabolismo , Actinas/genética , Animais , Western Blotting , Células Cultivadas , Colina/metabolismo , Deficiência de Colina , Dieta , Imunofluorescência , Células Estreladas do Fígado/citologia , Técnicas Imunoenzimáticas , Masculino , Metionina/deficiência , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Hepatopatia Gordurosa não Alcoólica/genética , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/patologia , RNA Mensageiro/genética , Reação em Cadeia da Polimerase em Tempo Real , Receptores Acoplados a Proteínas G/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Succinato Desidrogenase/genética
14.
Biochem Biophys Res Commun ; 463(4): 1064-70, 2015 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-26079881

RESUMO

Although SIGN-R1-mediated complement activation pathway has been shown to enhance the systemic clearance of apoptotic cells, the role of SIGN-R1 in the clearance of radiation-induced apoptotic cells has not been characterized and was investigated in this study. Our data indicated that whole-body γ-irradiation of mice increased caspase-3(+) apoptotic lymphocyte numbers in secondary lymphoid organs. Following γ-irradiation, SIGN-R1 and complements (C4 and C3) were simultaneously increased only in the mice spleen tissue among the assessed tissues. In particular, C3 was exclusively activated in the spleen. The delayed clearance of apoptotic cells was markedly prevalent in the spleen and liver of SIGN-R1 KO mice, followed by a significant increase of CD11b(+) cells. These results indicate that SIGN-R1 and complement factors play an important role in the systemic clearance of radiation-induced apoptotic innate immune cells to maintain tissue homeostasis after γ-irradiation.


Assuntos
Apoptose/fisiologia , Moléculas de Adesão Celular/fisiologia , Proteínas do Sistema Complemento/fisiologia , Lectinas Tipo C/fisiologia , Receptores de Superfície Celular/fisiologia , Irradiação Corporal Total , Animais , Apoptose/efeitos da radiação , Raios gama , Humanos , Linfócitos/citologia , Linfócitos/efeitos da radiação , Tecido Linfoide/citologia , Tecido Linfoide/efeitos da radiação , Macrófagos/citologia , Macrófagos/efeitos da radiação , Camundongos Endogâmicos C57BL
15.
Korean J Gastroenterol ; 63(4): 239-43, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24755749

RESUMO

Primary aortoenteric fistula (PAEF) is a rare but catastrophic cause of massive gastrointestinal bleeding. Diagnosis of PAEF is difficult to make and is frequently delayed without strong clinical suspicion. Timely surgical intervention is essential for patient's survival. We report on a case of an 86-year-old woman with no history of abdominal surgery, who presented with abdominal pain. Initially, computed tomography scan showed an intra-abdominal abscess, located anterior to the aortic bifurcation. However, she was discharged without treatment because of spontaneous improvement on a follow-up computed tomography scan, which showed a newly developed right common iliac artery aneurysm. One week later, she was readmitted due to recurrent abdominal pain. On the second day of admission, sudden onset of gastrointestinal bleeding occurred for the first time. After several endoscopic examinations, an aortoenteric fistula bleeding site was found in the sigmoid colon, and aortography showed progression of a right common iliac artery aneurysm. We finally concluded that intra-abdominal abscess induced an infected aortic aneurysm and enteric fistula to the sigmoid colon. This case demonstrated an extremely rare type of PAEF to the sigmoid colon caused by an infected abdominal aortic aneurysm, which has rarely been reported.


Assuntos
Abscesso Abdominal/diagnóstico , Aneurisma da Aorta Abdominal/diagnóstico , Fístula/diagnóstico , Abscesso Abdominal/microbiologia , Idoso de 80 Anos ou mais , Aorta Abdominal/diagnóstico por imagem , Aneurisma da Aorta Abdominal/etiologia , Bacteroides/isolamento & purificação , Bacteroides fragilis/isolamento & purificação , Colo Sigmoide/diagnóstico por imagem , Colonoscopia , Enterococcus/isolamento & purificação , Feminino , Humanos , Tomografia Computadorizada por Raios X
16.
Stem Cells Dev ; 23(6): 618-30, 2014 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-24219242

RESUMO

Recently, the involvement of PIN1, a peptidyl-prolyl cis/trans isomerase, has been reported in age-related bone homeostasis and adipogenesis. However, the role of PIN1 during odontogenic and adipogenic differentiation remains to be fully understood, particularly regarding human dental pulp stem cells (HDPSCs). Thus, in the present study, we have investigated the role of PIN1 in odontogenic and adipogenic differentiation of HDPSCs and signaling pathways possibly involved. PIN1 mRNA and protein level were upregulated in a time-dependent manner during adipogenic differentiation, increasing until 1 day of odontogenic induction and then steadily declined during odontogenic differentiation. Treatment of a known PIN1 inhibitor, juglone, significantly increased odontogenic differentiation as confirmed by alkaline phosphatase (ALP) activity, calcium deposition, and mRNAs induction of odontogenic markers [ALP, osteopontin (OPN), osteocalcin (OCN), dentin sialophosphoprotein (DSPP), and dentin matrix protein 1 (DMP-1)]. On the contrary, adipogenic differentiation was dramatically reduced upon juglone treatment, with concomitant downregulation of lipid droplet accumulation and adipogenic marker genes [peroxisome proliferation-activated receptor gamma (PPARγ), lipoprotein lipase (LPL), and adipocyte fatty acid-binding protein (AP2)]. In contrast to PIN1 inhibition, the overexpression of PIN1 via adenoviral infection (Ad-PIN1) in HDPSCs inhibited odontogenic differentiation but increased adipogenic differentiation, in which stem cell property markers such as stage-specific embryonic antigen-4 (SSEA-4) and STRO-1 were upregulated during odontogenic differentiation but downregulated in adiopogenic differentiation. Consistently, juglone-mediated inhibition of PIN1 augmented the osteogenic medium (OM)-induced activation of bone morphogenetic protein (BMP), Wnt/ß-catenin, extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and nuclear factor-kappa B (NF-κB) pathway, which response was reversed by Ad-PIN1. Moreover, juglone blocked the adipogenic induction medium-induced activation of PPARγ, C/EBPα, C/EBPß, ERK, and NF-κB pathways, which was rescued by Ad-PIN1 infection. In summary, the present study shows for the first time that PIN1 acts as an important modulator of odontogenic and adipogenic differentiation of HDPSCs and may have clinical implications for regenerative dentistry.


Assuntos
Adipogenia/fisiologia , Polpa Dentária/citologia , Odontogênese/fisiologia , Peptidilprolil Isomerase/metabolismo , Células-Tronco/citologia , Proteínas Morfogenéticas Ósseas/metabolismo , Humanos , Peptidilprolil Isomerase de Interação com NIMA , Transdução de Sinais/genética , Transdução de Sinais/fisiologia , Fator de Crescimento Transformador beta/genética , beta Catenina/metabolismo
17.
J Lifestyle Med ; 4(2): 80-5, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26064858

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is a hepatic presentation of obesity and metabolic syndrome. NAFLD includes a large spectrum of hepatic pathologies that range from simple steatosis and non-alcoholic steatohepatitis (NASH), to liver cirrhosis without an all-encompassing approved therapeutic strategy. Mitochondrial dysfunction is a key component of many metabolic diseases, such as obesity, type 2 diabetes, cancer, NAFLD, and aging. Sirtuin 3 (SIRT3) is a NAD(+)-dependent deacetylase that regulates many of the mitochondrial proteins that are involved with metabolic homeostasis, oxidative stress, and cell survival. This review discusses the association between mitochondrial dysfunction and insulin resistance and later explore the possibility that SIRT3 plays a protective role against NAFLD by improving mitochondrial dysfunction.

18.
J Korean Med Sci ; 28(10): 1496-9, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24133355

RESUMO

Osteopontin (OPN) is an acidic, noncollagenous matrix protein produced by the bone and kidneys. It is reportedly involved in bone resorption and formation. We examined the association between serum OPN levels and bone mineral density in postmenopausal women. Premenopausal women (n=32) and postmenopausal women (n=409) participated in the study. We measured serum osteopontin levels and their relationships with bone mineral density and previous total fragility fractures. The postmenopausal women had higher mean serum OPN levels compared to the premenopausal women (43.6±25.9 vs 26.3±18.6 ng/mL; P<0.001). In the postmenopausal women, high serum OPN levels were negatively correlated with mean lumbar bone mineral density (BMD) (r=-0.113, P=0.023). In a stepwise multiple linear regression model, serum OPN levels were associated with BMD of the spine, femoral neck, and total hip after adjustment for age, body mass index, smoking, and physical activity in postmenopausal women. However, serum OPN levels did not differ between postmenopausal women with and without fractures. Postmenopausal women exhibit higher serum OPN levels than premenopausal women and higher serum OPN levels were associated with low BMD in postmenopausal women.


Assuntos
Densidade Óssea/fisiologia , Osteopontina/sangue , Idoso , Feminino , Colo do Fêmur/metabolismo , Fraturas Ósseas/metabolismo , Fraturas Ósseas/patologia , Humanos , Modelos Lineares , Pessoa de Meia-Idade , Pós-Menopausa , Pré-Menopausa , Coluna Vertebral/metabolismo
19.
Int Immunopharmacol ; 15(4): 666-70, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23535020

RESUMO

Chaga mushrooms (Inonotus obliquus) are hypothesised to exhibit general immune-potentiating, anti-inflammatory, and antitumor properties, but their anti-allergic activities are not fully understood. Therefore, this study investigated whether a chaga mushroom extract (C-HE) might have anti-allergic activity. This activity was assessed through the levels of the IgE Ab produced in response to an allergen (OVA). The administration of C-HE prophylactically inhibited the systemic anaphylactic shock induced by compound 48/80 in mice. The oral administration of C-HE significantly reduced the total IgE levels in mice and slightly affected the production of IgG1. Furthermore, spleen cell cultures harvested from OVA-sensitised mice that had received C-HE orally showed a significant increase in Th1-derived responses (IFN-γ production). Therefore, our results suggest that the chaga mushroom extract may be used as an anti-allergic functional food.


Assuntos
Anafilaxia/prevenção & controle , Antialérgicos/uso terapêutico , Basidiomycota/química , Imunoglobulina E/sangue , p-Metoxi-N-metilfenetilamina/toxicidade , Anafilaxia/induzido quimicamente , Anafilaxia/imunologia , Animais , Antialérgicos/isolamento & purificação , Células Cultivadas , Feminino , Imunoglobulina E/imunologia , Interferon gama/biossíntese , Interferon gama/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/imunologia , Baço/citologia , Baço/efeitos dos fármacos , Baço/imunologia , Células Th1/efeitos dos fármacos , Células Th1/imunologia , p-Metoxi-N-metilfenetilamina/imunologia
20.
J Med Genet ; 50(4): 212-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23349225

RESUMO

BACKGROUND: Osteoporotic fracture (OF) as a clinical endpoint is a major complication of osteoporosis. To screen for OF susceptibility genes, we performed a genome-wide association study and carried out de novo replication analysis of an East Asian population. METHODS: Association was tested using a logistic regression analysis. A meta-analysis was performed on the combined results using effect size and standard errors estimated for each study. RESULTS: In a combined meta-analysis of a discovery cohort (288 cases and 1139 controls), three hospital based sets in replication stage I (462 cases and 1745 controls), and an independent ethnic group in replication stage II (369 cases and 560 for controls), we identified a new locus associated with OF (rs784288 in the MECOM gene) that showed genome-wide significance (p=3.59×10(-8); OR 1.39). RNA interference revealed that a MECOM knockdown suppresses osteoclastogenesis. CONCLUSIONS: Our findings provide new insights into the genetic architecture underlying OF in East Asians.


Assuntos
Proteínas de Ligação a DNA/genética , Osteoporose/genética , Fraturas por Osteoporose/genética , Proto-Oncogenes/genética , Locos de Características Quantitativas/genética , Fatores de Transcrição/genética , Idoso , Estudos de Casos e Controles , Regulação da Expressão Gênica , Técnicas de Silenciamento de Genes , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Proteína do Locus do Complexo MDS1 e EVI1 , Pessoa de Meia-Idade , Osteogênese/genética , Osteoporose/patologia , Fraturas por Osteoporose/patologia , Polimorfismo de Nucleotídeo Único
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