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1.
Int J Urol ; 30(12): 1122-1132, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37602677

RESUMO

OBJECTIVES: This study aims to reveal immunophenotypes associated with immunotherapy response in bladder cancer, identify the signature genes of immune subtypes, and provide new molecular targets for improving immunotherapy response. METHODS: Bladder cancer immunophenotypes were characterized in the bulk RNA sequencing dataset GSE32894 and Imvigor210, and gene expression signatures were established to identify the immunophenotypes. Expression of gene signatures were validated in single-cell RNA sequencing dataset GSE145140 and human proteins expression data source. Investigation of Immunotherapy Response was performed in IMvigor210 dataset. Prognosis of tumor immunophenotypes was further analyzed. RESULTS: Inflamed and immune-excluded immunophenotypes were characterized based on the tumor immune cell scores. Risk score models that were established rely on RNA sequencing profiles and overall survival of bladder cancer cohorts. The inflamed tumors had lower risk scores, and the low-risk tumors were more likely to respond to atezolizumab, receiving complete response/partial response (CR/PR). Patients who responded to atezolizumab had higher SRRM4 and lower NPHS1 and TMEM72 expression than the non-responders. SRRM4 expression was a protective factor for bladder cancer prognosis, while the NPHS1 and TMEM72 showed the opposite pattern. CONCLUSION: This study provided a novel classification method for tumor immunophenotypes. Bladder cancer immunophenotypes can predict the response to immune checkpoint blockade. The immunophenotypes can be identified by the expression of signature genes.


Assuntos
Síndrome Nefrótica , Neoplasias da Bexiga Urinária , Humanos , Neoplasias da Bexiga Urinária/tratamento farmacológico , Neoplasias da Bexiga Urinária/genética , Bexiga Urinária , Imunoterapia , Microambiente Tumoral , Prognóstico , Proteínas do Tecido Nervoso
2.
J Formos Med Assoc ; 122(10): 1028-1034, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37311680

RESUMO

BACKGROUND: The mitochondrial DNA m.3243A>G mutation can affect mitochondrial function and lead to a wide phenotypic spectrum, including mitochondrial encephalopathy with lactic acidosis and stroke-like episodes (MELAS) syndrome, diabetes mellitus, hearing impairment, cardiac involvement, epilepsy, migraine, myopathy, and cerebellar ataxia. However, m.3243A>G has been rarely reported in patients with cerebellar ataxia as their predominant manifestation. The aim of this study is to investigate the prevalence and clinical features of m.3243A>G in a Taiwanese cohort of cerebellar ataxia with unknown genetic diagnosis. METHODS: This retrospective cohort study conducted the mutation analysis of m.3243A>G by polymerase chain reaction and restriction fragment length polymorphism (PCR-RFLP) in 232 unrelated Han Chinese patients with genetically-undetermined cerebellar ataxia. The clinical presentation and neuroimaging features of patients with m.3243A>G mutation-related cerebellar ataxia were characterized. RESULTS: We identified two patients harboring m.3243A>G mutation. These patients have suffered from apparently sporadic and slowly progressive cerebellar ataxia since age 52 and 35 years, respectively. Both patients had diabetes mellitus and/or hearing impairment. The neuroimaging studies revealed generalized brain atrophy with predominantly cerebellar involvement in both individuals and bilateral basal ganglia calcifications in one of the patients. CONCLUSION: Mitochondrial m.3243A>G mutation accounted for 0.9% (2/232) of genetically-undetermined cerebellar ataxia in the Han Chinese cohort in Taiwan. These findings highlight the importance of investigating m.3243A>G in patients with genetically-undetermined cerebellar ataxia.


Assuntos
Ataxia Cerebelar , Diabetes Mellitus , Perda Auditiva , Humanos , Estudos Retrospectivos , Ataxia Cerebelar/genética , Mutação , DNA Mitocondrial/genética
3.
Acta Neurol Taiwan ; 31(2): 79-83, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35266136

RESUMO

PURPOSE: To propose that transient postictal hyperglycemia as a diagnostic clue of mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS). CASE REPORT: We reported two non-diabetic patients presenting with generalized seizure and transient postictal hyperglycemia. At the acute stage, both patients had hyperglycemia with serum glucose levels more than 400 mg/dl, normal glycated hemoglobin (HbA1C) levels, normal ketone body levels, and absence of infection signs. Within three days of the seizure event, both patients were euglycemic and did not require any diabetes treatment. Brain MRI examination revealed gyriform restricted diffusion at bilateral superior temporal gyrus in one patient, and diffuse cerebral and cerebellar atrophy without restricted diffusion lesions in another patient. Polymerase chain reaction and restriction fragment length polymorphism (RFLP) analysis confirmed that both patients harbored the m.3243A more than G mutation. CONCLUSION: Seizure-induced stress hyperglycemia is uncommon in normal individuals, but such kind of energy crisis may be pronounced in patients with mitochondrial dysfunction. Early diagnosis of mitochondrial diseases-related epilepsy and hyperglycemia is crucial since certain antiepileptic drugs (ex. Valproic acid) and antihyperglycemic agents (ex. Metformin) are contraindicated in patients with mitochondrial diseases. Our findings support that transient postictal hyperglycemia may be a red flag to consider the diagnosis of MELAS.


Assuntos
Acidose Láctica , Hiperglicemia , Síndrome MELAS , Acidente Vascular Cerebral , Acidose Láctica/complicações , Humanos , Hiperglicemia/complicações , Síndrome MELAS/complicações , Síndrome MELAS/diagnóstico , Síndrome MELAS/genética , Mutação
5.
Cell Biol Int ; 42(4): 425-434, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29144590

RESUMO

Hepatocellular carcinoma (HCC) causes death mainly by disseminated metastasis progression from the organ being confined. Different metastatic stages are closely related to cellular metabolic profiles. Normal hepatocyte and HepG2 cell line from low metastatic HCC were studied by NMR-based metabolomic techniques. Multivariate and univariate statistical analyses were utilized to identify characteristic metabolites from cells and cultured media. Elevated levels of acetate, creatine, isoleucine, leucine, and phenylalanine were observed in HepG2 cells, suggesting more active in gathering nutrient components along with altered amino acid metabolisms and enhanced lipid metabolism. High glucose consumption was significantly different in low metastatic cells. A series of characteristic metabolites were identified and served as biomarkers. Relative metabolic pathway analysis shows that low metastatic HepG2 cell line exhibits active behaviors in metabolisms and biosynthesis of specific amino acids and energy metabolism. Moreover, characteristic metabolites-based classification models executed by support vector machines algorithm perform robustly to classify normal hepatocyte and HepG2 cell line. It is concluded that NMR-based metabolomic analyses of cell lines can provide a powerful approach to understand metastasis-related biological alterations. The present study also provides a basis for metabolic markers determination of hepatic carcinoma in the future clinical study.


Assuntos
Carcinoma Hepatocelular/metabolismo , Hepatócitos/metabolismo , Neoplasias Hepáticas/metabolismo , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/diagnóstico por imagem , Carcinoma Hepatocelular/patologia , Linhagem Celular , Células Cultivadas , Metabolismo Energético , Células Hep G2 , Humanos , Metabolismo dos Lipídeos , Neoplasias Hepáticas/diagnóstico por imagem , Neoplasias Hepáticas/patologia , Espectroscopia de Ressonância Magnética/métodos , Redes e Vias Metabólicas , Metaboloma , Metabolômica
7.
Gen Comp Endocrinol ; 242: 92-100, 2017 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-26497252

RESUMO

Glucotoxicity and lipotoxicity are major hallmarks of metabolic disorder. High consumption of fat or carbohydrate rich food is a major risk of metabolic disorder. However, the evolution of high fat or high carbohydrate diet-induced metabolic disorder is not clear. In the study, we tried to find distinguished and common ways involved in the pathogenesis of insulin resistance induced by high fat (HF) and high sucrose (HS) diet. We found that HS diet induced mild glucose intolerance (2month), followed by a "temporary non-symptom phase" (3month), and then induced significant metabolic abnormality (4month). HF diet induced an early "responsive enhancement phase" (2month), and then gradually caused severe metabolic dysfunction (3-4month). After a mild induction of mitochondrial ROS generation (2month), HS diet resulted in a "temporary non-symptom phase" (3month), and then induced a more significant mitochondrial ROS production (4month). The impairment of mitochondrial function induced by HS diet was progressive (2-4month). HF diet induced gradual mitochondrial ROS generation and hyperpolarization. HF diet induced an early "responsive enhancement" of mitochondrial function (2month), and then gradually resulted in severe decrease of mitochondrial function (3-4month). Despite the patterns of HS and HF diet-induced insulin resistance were differential, final mitochondrial ROS generation combined with mitochondrial dysfunction may be the common pathway. These findings demonstrate a novel understanding of the mechanism of insulin resistance and highlight the pivotal role of mitochondrial ROS generation and mitochondrial dysfunction in the pathogenesis of metabolic disorder.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Sacarose Alimentar/efeitos adversos , Mitocôndrias/efeitos dos fármacos , Animais , Sacarose Alimentar/administração & dosagem , Metabolismo Energético , Glucose/metabolismo , Intolerância à Glucose/metabolismo , Insulina/metabolismo , Resistência à Insulina , Masculino , Doenças Metabólicas , Mitocôndrias/fisiologia , Oxirredução , Estresse Oxidativo , Ratos
8.
Carcinogenesis ; 34(6): 1323-30, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23404993

RESUMO

Incidence of hepatocellular carcinoma (HCC) is dramatically increasing and is the third cause of cancer death worldwide. One key approach to control HCC is chemoprevention by naturally occurring agents. This study aims at investigating the antitumor effect of oleanolic acid (OA) and the molecular mechanisms. BALB/c mice were injected subcutaneously with HepG2 cells to establish transplanted tumors. Apoptosis and cell cycle arrest-related markers and signaling cascades were determined by western blot, immunofluorescence, reverse transcriptase-polymerase chain reaction and flow cytometric analysis. OA exhibited inhibitory effect on HCC through induction of apoptosis and cell cycle arrest both in transplanted tumors and in HepG2 cells. OA induced apoptosis through mitochondrial pathway, evidenced by inhibition of Akt/mammalian target of rapamycin pathway, mitochondrial dysfunction, transient increase of adenosine triphosphate, increase of Bax/Bcl-2 ratio, increased release of cytochrome c and activation of caspase/poly (ADP-ribose) polymerase. Activation of mitochondrial apoptotic pathway may be due to reactive oxygen species generated by mitochondrial fatty acid oxidation, resulted from enhancement of lipolysis regulated by cyclic adenosine 3',5'-monophosphate response element-binding protein-hormone-sensitive lipase/peroxisome proliferator-activated receptor γ signaling. OA induced G2/M cell cycle arrest through p21-mediated downregulation of cyclin B1/cdc2. Cyclooxygenase-2 (COX-2) and p53 were involved in OA-exerted effect, and extracellular signal-regulated kinase-p53 signaling played a central role in OA-activated cascades responsible for apoptosis and cell cycle arrest. OA demonstrated significant antitumor activities in HCC in vivo and in vitro models. These data provide new insights into the mechanisms underlying the antitumor effect of OA.


Assuntos
Antineoplásicos/farmacologia , Carcinoma Hepatocelular/tratamento farmacológico , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Neoplasias Hepáticas/tratamento farmacológico , Ácido Oleanólico/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Trifosfato de Adenosina/biossíntese , Animais , Apoptose/efeitos dos fármacos , Proteína Quinase CDC2/biossíntese , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ciclina B1/biossíntese , Ciclo-Oxigenase 2/biossíntese , Citocromos c/metabolismo , Pontos de Checagem da Fase G2 do Ciclo Celular , Células Hep G2 , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Mitocôndrias/metabolismo , Transplante de Neoplasias , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Espécies Reativas de Oxigênio/metabolismo , Serina-Treonina Quinases TOR/antagonistas & inibidores , Transplante Heterólogo
9.
Foods ; 12(1)2022 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-36613372

RESUMO

Contemporary pharmacological studies have reported that freshwater clam (Corbicula fluminea) can provide a broad spectrum of bioactivities, including antioxidant, anticancer, antihypertensive, hepatoprotective, and hypocholesterolemic effects. The aim of this study was to evaluate the gastroprotective effects of water extract of freshwater clam (WEC) on indomethacin (IND)-induced gastric mucosal cell damage in vitro and gastric ulcer in vivo. The cell viability of rat gastric mucosa RGM-1 cells was markedly decreased by 0.8 mM of IND treatment, and pre-treated with various concentration of WEC significantly restored IND-induced cell damage in a dose-dependent manner. WEC also significantly attenuated the elevated reactive oxygen species (ROS) levels, inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) expression, and nuclear factor-κB (NF-κB) p65 nuclear translocation induced by IND. In the in vivo study, IND caused severe gastric ulcer in Wistar rats, while WEC pretreatment effectively reduced the ulcer area and edema in the submucosa. We found that WEC significantly restored glutathione (GSH) content in gastric mucosa in a dose-dependent manner (p < 0.05). The reduction of prostaglandin E2 (PGE2) caused by IND was also improved with higher doses of WEC administration. Moreover, the overexpression of COX-2, iNOS, and tumor necrosis factor-α (TNF-α) proteins in gastric mucosa was downregulated by administration of WEC. Consequently, WEC can be used as a potential nutritional supplement to improve NSAIDs-caused gastric mucosal lesions.

10.
Microbiol Resour Announc ; 11(11): e0090522, 2022 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-36314918

RESUMO

Bacteriophage TaidaOne was isolated from soil collected in Taipei, Taiwan, using the host Streptomyces griseus. It is a siphovirus with a 56,183-bp genome that contains 86 protein-coding genes. Based on gene content similarity, it was assigned to actinobacteriophage subcluster BI1, within which only TaidaOne and GirlPower genomes contain an acetyltransferase homolog gene.

11.
Phytother Res ; 25(7): 1031-40, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21254272

RESUMO

Diabetes mellitus (DM) is a metabolic disorder characterized by chronic hyperglycemia. Although the clear mechanisms of DM and insulin resistance are still to be cleared, it has been well documented that reactive oxygen species (ROS) play a pivotal role in DM and multiple types of insulin resistance. For the past few years, natural substances have been shown to have the potential to treatment DM. Attention has been especially focused on plants rich in triterpenoids, which generally show antioxidant and antiglycation effect. In our previous studies, it was shown that oleanolic acid (OA), a natural triterpenoid and an aglycone of many saponins, is a potent antioxidant acting as not only a free radical-scavenger through direct chemical reactions but also as a biological molecule, which may enhance the antioxidant defenses. The present study aimed to investigate the potential antidiabetic effect of OA. Oleanolic acid showed a significant blood glucose-lowering and weight-losing effect in diabetic animals induced by streptozotocin (STZ). In the insulin resistant model, it was also shown that OA may promote insulin signal transduction and inhibit oxidative stress-induced hepatic insulin resistance and gluconeogenesis, in which process the phosphorylation of ERK and the protective effect on mitochondrial function may be involved. These findings may significantly better the understanding of the pharmacological actions of OA and advance therapeutic approaches to DM.


Assuntos
Diabetes Mellitus Experimental/tratamento farmacológico , Hipoglicemiantes/farmacologia , Ácido Oleanólico/farmacologia , Animais , Antioxidantes/farmacologia , Glicemia/efeitos dos fármacos , Linhagem Celular , Hepatócitos/efeitos dos fármacos , Humanos , Insulina/metabolismo , Resistência à Insulina , Masculino , Potencial da Membrana Mitocondrial , Estresse Oxidativo/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/farmacologia , Transdução de Sinais/efeitos dos fármacos
12.
Neurobiol Aging ; 97: 145.e5-145.e6, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32950272

RESUMO

Mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) and cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) are 2 monogenic cerebral small vessel diseases sharing several common clinical features including young stroke, migraine, and cognitive dysfunction. The aim of this study was to understand the role of MELAS in patients with CADASIL-like manifestations. We screened 429 unrelated patients with genetically unassigned CADASIL-like syndrome for mitochondrial DNA m.3243A>G mutation. None of them were found to have the mutation. Our finding suggests that m.3243A>G rarely causes CADASIL-like phenotype. It may be not necessary to consider MELAS as a differential diagnosis of CADASIL. Screening m.3243A>G in patients with CADASIL-like phenotype is of limited value.


Assuntos
CADASIL/genética , DNA Mitocondrial/genética , Mutação/genética , Fenótipo , CADASIL/diagnóstico , Diagnóstico Diferencial , Feminino , Humanos , Síndrome MELAS , Masculino
13.
Sci Total Environ ; 720: 137597, 2020 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-32143051

RESUMO

Polychlorinated biphenyls (PCBs) exposure is closely associated with the prevalence of metabolic diseases, including fatty liver and dyslipidemia. Emerging literature suggests that disturbance of gut microbiota is related to PCB126-induced metabolic disorders. However, the causal role of dysbiosis in PCB126-induced fatty liver is still unknown. To clarify the role of the gut microbiome in the detoxification of PCB126 in intestine or PCB126-induced toxicity in liver, mice were administrated with drinking water containing antibiotics (ampicillin, vancomycin, neomycin, and metronidazole) or Inulin. We showed that PCB126 resulted in significant hepatic lipid accumulation, inflammation, and fibrosis. PCB126, Antibiotics, and Inulin significantly affected the structure and shifted community membership of gut microbiome. 7 KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways at level 2 and 39 KEGG pathways at level 3 were significantly affected. Antibiotics alleviated PCB126-induced fibrosis in the liver but increased inflammation. Inulin treatment ameliorated both inflammation and fibrosis in the liver of PCB126-treated mice. Neither Antibiotics nor Inulin had significant effect on PCB126-induced hepatic steatosis. The more specific intervention of gut microbiota is needed to alleviate PCB126-induced fatty liver. These data demonstrate that homeostasis of gut microbiota is critical for the defense against PCB126 toxicity and dysbiosis plays a fundamental role in the development of inflammation and fibrosis in liver of PCB126-treated mice.


Assuntos
Microbioma Gastrointestinal , Animais , Disbiose , Homeostase , Fígado , Camundongos , Bifenilos Policlorados
14.
Biomed Pharmacother ; 108: 1181-1187, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30372819

RESUMO

Obesity, diabetes and related metabolic disorders are among the top prevalent metabolism-related diseases with increasing threat to human health throughout the world. Oleanolic acid (OA) is a natural triterpenoid and an aglycone of many saponins possessing anti-diabetic, antioxidant, hypolipidemic and anti-inflammatory activities. A nano-formulation of OA was recently developed to evaluate the efficiency of nano-OA in the treatment of insulin-resistance and metabolic disorders in high fat and fructose (HFF) diet-fed rats. This study further identified that nano-OA could reduce the increase of body weights, serum insulin, insulin sensitivity index, serum triglycerides, and cholesterol in HFF-fed rats. In consistence, nano-OA was able to attenuate HFF diet-induced lipid accumulation in the liver and improve the structural integrity of mitochondria and endoplasmic reticulum in liver and pancreas in animals fed with HFF diet. In addition, nan-OA can efficaciously mitigate the increase of levels of malondialdehyde (MDA) and nitric oxide (NO), and serum superoxide dismutase (SOD) and catalase (CAT) activities in blood samples. The beneficial effects of nano-OA was further evidenced to be superior to OA formulated in arabic gum and rosiglitazone treatment. Together, this study provides the evidence that nano-OA can effectively improve HFF diet-induced metabolic dysfunctions in rats by improving its bioavailability and pharmacodynamic properties and thus nano-OA may be a potentially efficient agent to treat obesity-related diabetes and metabolic disorders.


Assuntos
Doenças Metabólicas/tratamento farmacológico , Nanopartículas/química , Ácido Oleanólico/uso terapêutico , Animais , Dieta Hiperlipídica , Frutose , Resistência à Insulina , Metabolismo dos Lipídeos/efeitos dos fármacos , Fígado/lesões , Fígado/metabolismo , Fígado/patologia , Fígado/ultraestrutura , Masculino , Doenças Metabólicas/patologia , Ácido Oleanólico/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Pâncreas/efeitos dos fármacos , Pâncreas/lesões , Pâncreas/patologia , Pâncreas/ultraestrutura , Ratos Sprague-Dawley
15.
Cell Death Differ ; 24(9): 1588-1597, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-28622294

RESUMO

Hepatocyte nuclear factor 1b (HNF1b) is a transcription factor belonging to the HNF family. We aimed to investigate the role of HNF1b in white adipocyte differentiation. The expression of HNF1b was reduced in white adipose tissue (WAT) of both diet-induced and genetic obese mice and decreased during the process of 3T3-L1 adipocyte differentiation. Downregulation of HNF1b enhanced 3T3-L1 adipocyte differentiation and upregulation of HNF1b inhibited this process. Upregulation of HNF1b inhibited peroxisome proliferator-activated receptor γ (PPARγ) and its target gene expression, while downregulation of HNF1b increased those genes expression. Overexpression of PPARγ suppressed HNF1b upregulation-induced inhibition of adipocyte differentiation. HNF1b can directly bind with the promoter of PPARγ in 3T3-L1 cells, which was decreased after adipogenic differentiation. HNF1b promoted apoptotic and autophagic cell death in early differentiated adipocytes through regulation of cell cycle progress and cell death-related factors, and thus inhibited the process of mitotic clonal expansion (MCE). HNF1b acted as an antioxidant regulator through regulating various antioxidant enzymes via binding with antioxidant response element. Oxidant treatment suppressed HNF1b upregulation-induced inhibition of adipocyte differentiation. Overall, our results suggest that HNF1b is a novel negative regulator of adipocyte differentiation through regulation of PPARγ signaling, MCE and redox state.


Assuntos
Adipócitos Brancos/citologia , Adipócitos Brancos/metabolismo , Adipogenia/fisiologia , Diferenciação Celular/fisiologia , Células 3T3-L1 , Adipogenia/genética , Animais , Diferenciação Celular/genética , Regulação da Expressão Gênica , Fator 1-beta Nuclear de Hepatócito/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Oxirredução , PPAR gama/metabolismo , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real
17.
Int J Biol Sci ; 12(2): 198-209, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26884717

RESUMO

P53 is known as a transcription factor to control apoptotic cell death through regulating a series of target genes in nucleus. There is accumulating evidences show that p53 can directly induce cell apoptosis through transcription independent way at mitochondria. However, the mechanism by which p53 translocation into mitochondria in response to oxidative stress remains unclear. Here, glucose oxidase (GOX) was used to induce ROS generation in HepG2 cells and liver tissues of mice. The results showed that p53 was stabilized and translocated to mitochondria in a time and dose dependent manner after GOX exposure. Interestingly, as an inhibitor of mitochondrial permeability transition, cyclosporine A (CsA) was able to effectively reduce GOX mediated mitochondrial p53 distribution without influencing on the expression of p53 target genes including Bcl-2 and Bax. These indicated that CsA could just block p53 entering into mitochondria, but not affect p53-dependent transcription. Meanwhile, CsA failed to inhibit the ROS generation induced by GOX, which indicated that CsA had no antioxidant function. Moreover, GOX induced typical apoptosis characteristics including, mitochondrial dysfunction, accumulation of Bax and release of cytochrome C in mitochondria, accompanied with activation of caspase-9 and caspase-3. These processions were suppressed after pretreatment with CsA and pifithrin-µ (PFT-µ, a specific inhibitor of p53 mitochondrial translocation). In vivo, CsA was able to attenuate p53 mitochondrial distribution and protect mice liver against from GOX mediated apoptotic cell death. Taken together, these suggested that CsA could suppress ROS-mediated p53 mitochondrial distribution and cell apoptosis depended on its inhibition effect to mitochondrial permeability transition. It might be used to rescue the hepatic cell apoptosis in the patients with acute liver injury.


Assuntos
Ciclosporina/farmacologia , Glucose Oxidase/farmacologia , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Animais , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Caspase 3/metabolismo , Caspase 9/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Citocromos c/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Glucose Oxidase/metabolismo , Células Hep G2 , Humanos , Hepatopatias/metabolismo , Hepatopatias/patologia , Masculino , Camundongos , Camundongos Endogâmicos , Membranas Mitocondriais/efeitos dos fármacos , Membranas Mitocondriais/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Sulfonamidas/farmacologia , Proteína Supressora de Tumor p53/fisiologia , Proteína X Associada a bcl-2/genética , Proteína X Associada a bcl-2/metabolismo
18.
Toxicol Lett ; 224(1): 16-23, 2014 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-24140496

RESUMO

Insulin resistance is the hallmark of type 2 diabetes. As an essential trace element, selenium (Se) is recommended worldwide for supplementation to prevent Se-deficient pathological conditions, including diabetes and insulin resistance. However, recent evidence has shown that supra-nutritional Se intake is positively associated with the prevalence of diabetes. In the present research, we examined the effect of high Se on insulin sensitivity, and studied possible mechanisms in rats and in rat hepatocytes. Insulin sensitivity and glucose/lipid metabolism were determined by glucose/insulin tolerance test, western blot, immunofluorescence, specific probes and other biochemical assays. We show that high Se activates selenoproteins, including glutathione peroxidase and selenoprotein P, and depletes chromium, leading to a common metabolic intersection-lipolysis in adipose tissue and influx of fatty acids in liver. Fatty acid ß-oxidation generates acetyl-CoA, which is metabolized in trichloroacetic acid cycle, supplying excessive electrons for mitochondrial oxidative phosphorylation and leading to increased "bad" reactive oxygen species (ROS) production in mitochondria and final disturbance of insulin signaling. Furthermore, high Se-activated selenoproteins also weaken insulin-stimulated "good" ROS signal generated by NAD(P)H oxidase, leading to attenuation of insulin signaling. Taken together, these data suggest that excessive intake of Se induces hepatic insulin resistance through opposite regulation of ROS.


Assuntos
Resistência à Insulina , Fígado/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo , Selênio/toxicidade , Animais , Cromo/deficiência , Ácidos Graxos não Esterificados/metabolismo , Fígado/metabolismo , Mitocôndrias/metabolismo , Ratos , Selenoproteínas/fisiologia
19.
Cancer Cytopathol ; 121(12): 695-702, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23861325

RESUMO

BACKGROUND: Glucose transporter 1 (GLUT1) is a hallmark of metabolic change in cancer cells. The objective of this study was to determine the role of GLUT1 protein in diagnosing malignant pleural effusions by enzyme-linked immunosorbent assay (ELISA) and immunocytochemistry. METHODS: In total, 82 pleural effusions were collected and classified as benign (n = 42), atypical (n = 8), or malignant (n = 32) based on cytologic diagnosis and etiology. GLUT1 protein levels in effusions were measured by ELISA. GLUT1 expression also was determined by immunocytochemistry using cell blocks. RESULTS: GLUT1 levels were significantly higher in the malignant group compared with the benign group. Receiver operating characteristic curve analysis of benign and malignant pleural effusions for GLUT1 yielded an area under the curve of 0.77, with a value of 1355.87 pg/dL as the optimal threshold for distinguishing benign from malignant effusions. With the ELISA method, the sensitivity, specificity, and accuracy were 78.1%, 69%, and 73%, respectively. Malignant effusion cell blocks were positive for GLUT1 expression in 84.4% of cases with 100% specificity and 93.2% accuracy. With the combination of high GLUT1 protein levels (>10,000 pg/dL) and immunocytochemistry to detect malignant pleural effusions, the sensitivity and accuracy increased to 93.8% and 94.6%, respectively. The GLUT1 level measured by ELISA and the GLUT1 expression detected by immunocytochemistry were positively correlated. In atypical effusions, 3 cases (37.5%) had GLUT1 levels higher than the cutoff value. CONCLUSIONS: The detection of GLUT1 protein by ELISA and immunocytochemistry may have utility in the diagnosis of malignant pleural effusions.


Assuntos
Biomarcadores Tumorais/metabolismo , Regulação Neoplásica da Expressão Gênica , Transportador de Glucose Tipo 1/genética , Derrame Pleural Maligno/diagnóstico , Derrame Pleural Maligno/genética , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Estudos de Coortes , Diagnóstico Diferencial , Ensaio de Imunoadsorção Enzimática , Feminino , Transportador de Glucose Tipo 1/metabolismo , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade , Estatísticas não Paramétricas
20.
Zhongguo Gu Shang ; 26(4): 349-53, 2013 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-23844502

RESUMO

Osteoclasts and osteoblasts are not exist alone,while communicating with each other through direct contact, diffusible paracrine factors and cell-bone matrix interaction. Co-culture system of osteoblast with osteoclast,including direct co-culture and indirect co-culture. It should be according to the ratio of osteoclasts and osteoblasts under the pathology, choosing the same species. Compared with lonely culture of osteoblasts or osteoclasts,co-culture system is much closer to the microenvironment in vivo. It benefits to explain the interactions between osteoblasts and osteoclasts, exploring molecular communication in bone diseases. It was mainly used to investigate the pharmacological mechanism of herbal and western medicine in bone remodeling. Some osteoporosis drugs (such as epimedium,sanchi, fructus psoraleae, ranelate strontium) not only promoted osteoblastic bone formation, but also inhibited osteoclastic bone resorption in the system,so as to balance bone homeostasis. At the same time,it has been used to study medical physics and assess biomedical materials in recent years. Considerably,the co-cultrue system will be used to study the subchondral bone remodeling and its pharmacological mechanism of herbal and western medicine in osteoarthritis.


Assuntos
Técnicas de Cocultura , Animais , Remodelação Óssea , Comunicação Celular , Humanos , Osteoblastos/citologia , Osteoclastos/citologia
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