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1.
Mikrochim Acta ; 191(5): 265, 2024 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-38625451

RESUMO

Sleep deprivation (SD) is highly prevalent in the modern technological world. Emerging evidence shows that sleep deprivation is associated with oxidative stress. At the organelle level, the Golgi apparatus actively participates in the stress response. In this study, to determine whether SD and Golgi apparatus stress are correlated, we rationally designed and fabricated a novel Golgi apparatus-targeted ratiometric nanoprobe called Golgi dots for O2·- detection. This probe exhibits high sensitivity and selectivity in cells and brain slices of sleep-deprived mice. Golgi dots can be readily synthesized by coprecipitation of Golgi-F127, an amphiphilic polymer F127 modified with a Golgi apparatus targeting moiety, caffeic acid (CA), the responsive unit for O2·-, and red emissive carbon nanodots (CDs), which act as the reference signal. The fluorescence emission spectrum of the developed nanoprobe showed an intense peak at 674 nm, accompanied by a shoulder peak at 485 nm. As O2·- was gradually added, the fluorescence at 485 nm continuously increased; in contrast, the emission intensity at 674 nm assigned to the CDs remained constant, resulting in the ratiometric sensing of O2·-. The present ratiometric nanoprobe showed high selectivity for O2·- monitoring due to the specific recognition of O2·- by CA. Moreover, the Golgi dots exhibited good linearity with respect to the O2·- concentration within 5 to 40 µM, and the limit of detection (LOD) was ~ 0.13 µM. Additionally, the Golgi dots showed low cytotoxicity and an ability to target the Golgi apparatus. Inspired by these excellent properties, we then applied the Golgi dots to successfully monitor exogenous and endogenous O2·- levels within the Golgi apparatus. Importantly, with the help of Golgi dots, we determined that SD substantially elevated O2·- levels in the brain.


Assuntos
Encéfalo , Ácidos Cafeicos , Polietilenos , Polipropilenos , Privação do Sono , Animais , Camundongos , Complexo de Golgi , Suplementos Nutricionais
2.
Foods ; 13(8)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38672824

RESUMO

Hydroponic cultivation of fresh produce is gaining popularity worldwide, but few studies have provided a comparative assessment of hydroponic and conventional soil-based vegetables. In this study, we analyzed a series of hazardous chemicals, including 120 pesticides, 18 phthalates (PAEs), and 2 heavy metals (lead and cadmium) in four vegetable commodities (lettuces, celeries, tomatoes, and cucumbers) from hydroponic and conventional soil-based cultivation. Our study showed that at least one pesticide was present in 84% of the conventionally grown samples, whereas only 30% of the hydroponic samples contained detectable pesticide residues. Regarding the total PAE concentrations, there was no significant difference between conventional and hydroponic vegetables. The lead and cadmium residues in conventionally cultivated vegetables were significantly higher than in those produced from hydroponic cultivation. Lead is the primary heavy metal pollutant across all vegetable samples. The hazard index (HI) values of the hydroponic and conventional vegetables were 0.22 and 0.64, respectively. Since both values are below one, the exposure to these hazardous chemicals through consumption of the studied vegetables may not pose a significant health risk. The HI values also suggested that the health risks of eating hydroponic vegetables are lower than for conventional soil-based vegetables.

3.
BMC Oral Health ; 23(1): 1023, 2023 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-38114973

RESUMO

BACKGROUND: Both cancer and periodontitis are more prevalent with age. Information on their relationship in older patients is limited. This study aims to examine whether periodontitis is associated with increased risk of cancer mortality with a ≥ 75-year age group cohort. METHODS: A retrospective cohort study was conducted on 1146 patients who had digital radiographic examinations. Alveolar bone loss and loss of teeth were measured as indicators of periodontitis. Hazard ratio (HR) with 95% confidence interval (CI) were taken as the effect size to summarize the associations between periodontitis and risks of cancer mortality using the multivariate adjusted cox proportional hazards model and competing risk hazard model. RESULTS: Totally, 104 total cancer, 28 lip, oral cavity and pharynx (LOP) cancer, 39 digestive cancer and 13 respiratory cancer cases were documented over 10 years of follow-up. Total cancer (HR 1.27, 95% CI 1.06-1.53) displayed statistically significant associations with alveolar bone loss and tooth loss after adjusting for relevant confounding variables. We also observed borderline significant association between alveolar bone loss and LOP cancer (HR 1.45, 95% CI 0.99-2.12). The above associations were consistent with the results observed from the competing risk hazard models. CONCLUSION: Our results indicate that older patients suffering from tooth loss or alveolar bone loss are at increased risks of cancer mortality, especially for total cancer and LOP cancer.


Assuntos
Perda do Osso Alveolar , Neoplasias , Periodontite , Perda de Dente , Humanos , Idoso , Perda de Dente/complicações , Perda do Osso Alveolar/diagnóstico por imagem , Perda do Osso Alveolar/etiologia , Estudos Retrospectivos , Periodontite/complicações , Neoplasias/complicações , Fatores de Risco
4.
Sci Total Environ ; 893: 164844, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37321506

RESUMO

As ubiquitous emerging pollutants, microplastics (MPs) in aquatic environments have aroused critical global concerns. Despite the occurrence and characteristics of MPs in freshwater agroecosystems well-described by our previous study, their ecotoxicological implications in Monopterus albus remains unfathomed. Herein, we dissected toxic effects and mechanisms of PS-NPs exposure against M. albus hepatic tissues at concentrations of 0.5 (L), 5 (M), 10 (H) mg/L for 28 days using physiochemical measurements, histopathological analysis and transcriptomic sequencing. Results showed that upon PS-NPs treatments, levels of ROS, MDA, 8-OHdG and MFO activity were significantly enhanced relative to the control (C) group, while SP content and T-AOC activity were dramatically suppressed, suggesting ROS burst, lipid peroxidation and DNA damage may occur in liver tissues. This oxidative damage further triggered impaired hepatic function and histopathology, disordered lipid metabolism and hepatocyte apoptosis, as reflected by significantly diminished activities of GPT, GOT, ACP, AKP and LDH, paralleled with augmented levels of TG, TC and HSI as well as Cytc and Caspase-3,8,9 activities. Noticeably, concentration-dependent rises of apoptotic rate, vacuolar degeneration and lipid deposition were manifest in TUNEL, H&E and ORO staining. In addition, a total of 375/475/981 up-regulated as well as 260/611/1422 down-regulated DEGs in C vs L, C vs M and C vs H categories were identified based on RNA-seq, respectively. These DEGs were significantly annotated and enriched into GO terms (membrane, cytoplasm, response to stimuli, oxidation-reduction process) as well as KEGG pathways (ether lipid metabolism, apoptosis, chemical carcinogenesis-reactive oxygen species, non-alcoholic fatty liver disease). Moreover, signaling cascades Keap1-Nrf2, p53 and PPAR were either substantially initiated or dysregulated to orchestrate PS-NPs hepatotoxicity featuring oxidative damage, hepatocyte apoptosis and lipid steatosis. Collectively, this study not only expounded on toxicological mechanisms whereby PS-MPs exerted deleterious effects on M. albus, but also pointed to ecological risks of PS-MPs-induced hepatoxicity and lipid steatosis in this commercially-important species.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Nanosferas , Smegmamorpha , Animais , Poliestirenos/toxicidade , Transcriptoma , Plásticos/metabolismo , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Smegmamorpha/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Microplásticos/toxicidade , Lipídeos
5.
Oncogene ; 41(49): 5223-5237, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36309571

RESUMO

Terminal differentiation failure is an important cause of rhabdomyosarcoma genesis, however, little is known about the epigenetic regulation of aberrant myogenic differentiation. Here, we show that GATA-4 recruits polycomb group proteins such as EZH2 to negatively regulate miR-29a in undifferentiated C2C12 myoblast cells, whereas recruitment of GRIP-1 to GATA-4 proteins displaces EZH2, resulting in the activation of miR-29a during myogenic differentiation of C2C12 cells. Moreover, in poorly differentiated rhabdomyosarcoma cells, EZH2 still binds to the miR-29a promoter with GATA-4 to mediate transcriptional repression of miR-29a. Interestingly, once re-differentiation of rhabdomyosarcoma cells toward skeletal muscle, EZH2 was dispelled from miR-29a promoter which is similar to that in myogenic differentiation of C2C12 cells. Eventually, this expression of miR-29a results in limited rhabdomyosarcoma cell proliferation and promotes myogenic differentiation. We thus establish that GATA-4 can function as a molecular switch in the up- and downregulation of miR-29a expression. We also demonstrate that GATA-4 acts as a tumor suppressor in rhabdomyosarcoma partly via miR-29a, which thus provides a potential therapeutic target for rhabdomyosarcoma.


Assuntos
MicroRNAs , Rabdomiossarcoma Embrionário , Rabdomiossarcoma , Animais , Camundongos , Diferenciação Celular/genética , Proliferação de Células/genética , Proteína Potenciadora do Homólogo 2 de Zeste/genética , Proteína Potenciadora do Homólogo 2 de Zeste/metabolismo , Epigênese Genética , MicroRNAs/metabolismo , Mioblastos , Rabdomiossarcoma/patologia , Rabdomiossarcoma Embrionário/patologia
6.
Cell Mol Biol Lett ; 25: 12, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32161621

RESUMO

BACKGROUND: MicroRNA-125b (miR-125b) is downregulated in human cutaneous squamous cell carcinoma (CSCC). However, its function in CSCC has yet to be extensively explored. Here, we analyze the relationship between signal transducer and activator of transcription 3 (STAT3) and miR-125b in CSCC. METHODS: Western blotting and quantitative RT-PCR were used to determine the expression of the miR-125b-STAT3 axis in human CSCC tissues and cell lines. The direct regulatory effect of miR-125b on STAT3 expression was assessed using a luciferase reporter gene assay and RNA immunoprecipitation assay. The MTT assay and flow cytometry were used to determine the role of the miR-125b-STAT3 axis in CSCC cell proliferation and apoptosis. RESULTS: MiR-125b expression levels were significantly lower in CSCC cell lines and tissues than in normal cell lines and tissues. STAT3 was identified as the direct target of miR-125b. Upregulation of miR-125b and downregulation of STAT3 suppressed cell proliferation and promoted cell apoptosis. Cyclin D1 and Bcl2 were identified as the downstream targets of the miR-125-STAT3 axis. CONCLUSIONS: Our findings indicate that miR-125b acts as a tumor suppressor in CSCC by targeting the STAT3 pathway. This observation increases our understanding of the molecular mechanisms of CSCC. Therapies aimed at activating miR-125b or inhibiting STAT3 signaling should be explored as potential treatments for CSCC.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , MicroRNAs/metabolismo , Fator de Transcrição STAT3/metabolismo , Neoplasias Cutâneas/metabolismo , Apoptose/genética , Carcinoma de Células Escamosas/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Ciclina D1/metabolismo , Humanos , MicroRNAs/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Fator de Transcrição STAT3/genética , Transdução de Sinais/genética , Neoplasias Cutâneas/genética
7.
BMC Public Health ; 19(1): 753, 2019 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-31196049

RESUMO

BACKGROUND: Tobacco smoking is a recognized risk factor for many chronic diseases and previous study evidences have indicated that smokers receive smoking cessation service after the diagnosis of chronic diseases increases successful rate in quitting. But the prevalence of tobacco related chronic diseases (TCD) among smokers, as well as the role of TCD diagnosis in smoking cessation is still unclear in China. METHODS: From June 2016 to December 2017, we sampled 36, 698 residents aged over 18 years by a three stage sampling in Songjiang district, Shanghai. We conducted a cross-sectional study to understand the prevalence of TCD among smokers, and the role of TCD diagnosis in smoking cessation among ex-smokers as well as the smoking cessation attempt among current smokers. RESULTS: Over all, the prevalence of current smoking is 19.78% (48.36% for male and 0.22% for female). 15.93% of smokers have stopped smoking successfully (1, 376/8, 636). The prevalence of ten selected TCDs among smokers range from 0.63% (Chronic Obstructive Pulmonary Disease, COPD) to 36.31% (hypertension). All of 1, 376 ex-smokers had at least one kind of TCD, and 52.33% of them stop smoking after the diagnosis of TCD, the time interval between TCD diagnosis and smoking cessation ranges from 0 to 65 years, with a median of 9 years. Smokers with TCD had higher prevalence of quit smoking, and current smokers with TCD had higher smoking cessation attempt proportion. CONCLUSIONS: The prevalence of current smoking is still very high among male residents in rural area of Shanghai, and the occurrence of TCD even non-lethal one could provide an opportunity for doctors to assist the smoking cessation among smokers.


Assuntos
Doença Crônica/epidemiologia , População Rural , Fumantes/psicologia , Abandono do Hábito de Fumar/psicologia , Fumar Tabaco/efeitos adversos , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Prevalência , Fatores de Risco , População Rural/estatística & dados numéricos , Fumantes/estatística & dados numéricos , Abandono do Hábito de Fumar/estatística & dados numéricos , Fumar Tabaco/epidemiologia , Adulto Jovem
8.
Circulation ; 138(20): 2227-2242, 2018 11 13.
Artigo em Inglês | MEDLINE | ID: mdl-29802206

RESUMO

BACKGROUND: Atrial fibrillation (AF) is frequently associated with enhanced inflammatory response. The NLRP3 (NACHT, LRR, and PYD domain containing protein 3) inflammasome mediates caspase-1 activation and interleukin-1ß release in immune cells but is not known to play a role in cardiomyocytes (CMs). Here, we assessed the role of CM NLRP3 inflammasome in AF. METHODS: NLRP3 inflammasome activation was assessed by immunoblot in atrial whole-tissue lysates and CMs from patients with paroxysmal AF or long-standing persistent (chronic) AF. To determine whether CM-specific activation of NLPR3 is sufficient to promote AF, a CM-specific knockin mouse model expressing constitutively active NLRP3 (CM-KI) was established. In vivo electrophysiology was used to assess atrial arrhythmia vulnerability. To evaluate the mechanism of AF, electric activation pattern, Ca2+ spark frequency, atrial effective refractory period, and morphology of atria were evaluated in CM-KI mice and wild-type littermates. RESULTS: NLRP3 inflammasome activity was increased in the atrial CMs of patients with paroxysmal AF and chronic AF. CM-KI mice developed spontaneous premature atrial contractions and inducible AF, which was attenuated by a specific NLRP3 inflammasome inhibitor, MCC950. CM-KI mice exhibited ectopic activity, abnormal sarcoplasmic reticulum Ca2+ release, atrial effective refractory period shortening, and atrial hypertrophy. Adeno-associated virus subtype-9-mediated CM-specific knockdown of Nlrp3 suppressed AF development in CM-KI mice. Finally, genetic inhibition of Nlrp3 prevented AF development in CREM transgenic mice, a well-characterized mouse model of spontaneous AF. CONCLUSIONS: Our study establishes a novel pathophysiological role for CM NLRP3 inflammasome signaling, with a mechanistic link to the pathogenesis of AF, and establishes the inhibition of NLRP3 as a potential novel AF therapy approach.


Assuntos
Fibrilação Atrial/patologia , Miócitos Cardíacos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Animais , Artérias/metabolismo , Artérias/patologia , Fibrilação Atrial/tratamento farmacológico , Fibrilação Atrial/metabolismo , Cálcio/metabolismo , Modelos Animais de Doenças , Cães , Eletroencefalografia , Furanos/farmacologia , Furanos/uso terapêutico , Compostos Heterocíclicos de 4 ou mais Anéis , Humanos , Hipertrofia/etiologia , Hipertrofia/prevenção & controle , Indenos , Inflamassomos/metabolismo , Camundongos , Camundongos Knockout , Proteína 3 que Contém Domínio de Pirina da Família NLR/antagonistas & inibidores , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Técnicas de Patch-Clamp , Interferência de RNA , RNA Interferente Pequeno/metabolismo , Retículo Sarcoplasmático/metabolismo , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Sulfonas
9.
Nutrients ; 9(3)2017 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-28282864

RESUMO

BACKGROUND: Few studies have applied the Chinese Diet Balance Index (DBI) in evaluating dietary quality across seasons. METHOD: The Shanghai Diet and Health Survey (SDHS) included 1680 participants from all districts of Shanghai from 2012 to 2013. Dietary data were obtained using three-day 24-h recall in spring, summer, fall, and winter. Higher bound score (HBS), lower bound score (LBS) and diet quality distance (DQD) were calculated according to compliance with the dietary guidelines and based on the recommendations for consumption within the main food groups. HBS, LBS, and DQD represent over-intake, under-intake, and overall imbalance of the diet, respectively. RESULTS: 836 males and 844 females were included. The HBS indicated that 10.08%, 11.84%, 10.31%, and 12.73% people have moderate or high levels of over-intake of food in spring, summer, fall, and winter, respectively; and 74.04%, 37.61%, 53.09%, and 42.72% people have moderate or high levels of deficit food intake for each of the four seasons. The mean HBS and LBS among the four seasons were statistically significant difference (p < 0.001). The mean (SD) DQD was 43.27 (10.21), 35.67 (9.71), 39.19 (9.36), and 36.84 (9.45) in each season. A multivariable model showed statistically significant differences in DQD according to age, gender, occupational status, education, smoking, drinking status, season, and residency (p < 0.001). CONCLUSION: An unbalanced diet is common among people living in Shanghai. Seasonality and area of residence were found to be two significant predictors. Strengthening the accessibility and the supply of food across seasons and regions should be considered.


Assuntos
Dieta , Qualidade dos Alimentos , Avaliação Nutricional , Política Nutricional , Estações do Ano , Adolescente , Adulto , Índice de Massa Corporal , China , Estudos de Coortes , Feminino , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores Socioeconômicos , Inquéritos e Questionários , Adulto Jovem
10.
J Cell Biochem ; 116(8): 1755-65, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25736800

RESUMO

It has been reported that the antitumor drug doxorubicin (Dox) exerts its toxic effects via GATA-4 depletion and that over-expression of GATA-4 reverses Dox-induced toxicity and apoptosis; however, the precise mechanisms remain unclear. In this study, we observed, for the first time, that EGF protects cells against Dox-mediated growth arrest, G2/M-phase arrest, and apoptosis. Additionally, EGF expression was down-regulated in Dox-treated cells and up-regulated in GATA-4 over-expressing cells. Utilizing real-time PCR and western blotting analysis, we found that the expression of the cell cycle-associated protein cyclin D1 was inhibited in GATA-4-silenced cells and Dox-treated cells and was enhanced in GATA-4 over-expressing cells and EGF-treated cells. Furthermore, EGF treatment reversed the inhibited expression of cyclin D1 that was mediated by GATA-4 RNAi or Dox. Our results indicate that EGF, as a downstream target of Dox, may be involved in Dox-induced toxicity as well as in the protective role of GATA-4 against toxicity induced by Dox via regulating cyclin D1 expression, which elucidates a new molecular mechanism of Dox toxicity with important clinical implications.


Assuntos
Antibióticos Antineoplásicos/farmacologia , Ciclina D1/metabolismo , Doxorrubicina/farmacologia , Fator de Crescimento Epidérmico/farmacologia , Fator de Transcrição GATA4/metabolismo , Animais , Apoptose , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Fator de Transcrição GATA4/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Humanos , Camundongos
11.
Dev Growth Differ ; 55(7): 676-86, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24020834

RESUMO

Insulin is a peptide hormone produced by beta cells of the pancreas. The roles of insulin in energy metabolism have been well studied, with most of the attention focused on glucose utilization, but the roles of insulin in cell proliferation and differentiation remain unclear. In this study, we observed for the first time that 10 nmol/L insulin treatment induces cell proliferation and cardiac differentiation of P19CL6 cells, whereas 50 and 100 nmol/L insulin treatment induces P19CL6 cell apoptosis and blocks cardiac differentiation of P19CL6 cells. By using real-time polymerase chain reaction (PCR) and Western blotting analysis, we found that the mRNA levels of cyclin D1 and α myosin heavy chain (α-MHC) are induced upon 10 nmol/L insulin stimulation and inhibited upon 50/100 nmol/L insulin treatment, whereas the mRNA levels of BCL-2-antagonist of cell death (BAD) exists a reverse trend. The similar results were observed in P19CL6 cells expressing GATA-6 or peroxisome proliferator-activated receptor α (PPARα). Our results identified the downstream targets of insulin, cyclin D1, BAD, α-MHC, and GATA-4, elucidate a novel molecular mechanism of insulin in promoting cell proliferation and differentiation.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Insulina/farmacologia , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Western Blotting , Diferenciação Celular/genética , Linhagem Celular Tumoral , Ciclina D1/genética , Ciclina D1/metabolismo , Relação Dose-Resposta a Droga , Citometria de Fluxo , Fator de Transcrição GATA4/genética , Fator de Transcrição GATA4/metabolismo , Fator de Transcrição GATA6/genética , Fator de Transcrição GATA6/metabolismo , Expressão Gênica/efeitos dos fármacos , Camundongos , Miócitos Cardíacos/efeitos dos fármacos , Miócitos Cardíacos/metabolismo , Cadeias Pesadas de Miosina/genética , Cadeias Pesadas de Miosina/metabolismo , PPAR alfa/genética , PPAR alfa/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteína de Morte Celular Associada a bcl/genética , Proteína de Morte Celular Associada a bcl/metabolismo
12.
J Cell Biochem ; 114(12): 2708-17, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23794242

RESUMO

Insulin is a secreted peptide hormone identified in human pancreas to promote glucose utilization. Insulin has been observed to induce cell proliferation and myogenesis in C2C12 cells. The precise mechanisms underlying the proliferation of C2C12 cells induced by insulin remain unclear. In this study, we observed for the first time that 10 nM insulin treatment promotes C2C12 cell proliferation. Additionally, 50 and 100 nM insulin treatment induces C2C12 cell apoptosis. By utilizing real-time PCR and Western blotting analysis, we found that the mRNA levels of cyclinD1 and BAD are induced upon 10 and 50 nM/100 nM insulin treatment, respectively. The similar results were observed in C2C12 cells expressing GATA-6 or PPARα. Our results identify for the first time the downstream targets of insulin, cyclin D1, and BAD, elucidate a new molecular mechanism of insulin in promoting cell proliferation and apoptosis.


Assuntos
Proliferação de Células , Ciclina D1/genética , Insulina/genética , Proteína de Morte Celular Associada a bcl/genética , Apoptose/genética , Linhagem Celular , Linhagem Celular Tumoral , Citometria de Fluxo , Fator de Transcrição GATA6/genética , Fator de Transcrição GATA6/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias/genética , Neoplasias/patologia , PPAR alfa/genética , PPAR alfa/metabolismo , Transdução de Sinais , Proteína de Morte Celular Associada a bcl/metabolismo
13.
RNA Biol ; 10(4): 465-80, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23558708

RESUMO

GATA-4 is an important transcription factor involved in several developmental processes of the heart, such as cardiac myocyte proliferation, differentiation and survival. The precise mechanisms underlying the regulation of GATA-4 remain unclear, this is especially true for the mechanisms that mediate the post-transcriptional regulation of GATA-4. Here, we demonstrate that miR-200b, a member of the miR-200 family, is a critical regulator of GATA-4. Overexpression of miR-200b leads to the downregulation of GATA-4 mRNA and a decrease in GATA-4 protein levels. Moreover, miR-200b not only inhibits cell growth and differentiation but also reverses the growth response mediated by GATA-4, whereas depletion of miR-200b leads to a slight reversal of the anti-growth response achieved by knocking down endogenous GATA-4. More importantly, the cell cycle-associated gene cyclin D1, which is a downstream target of GATA-4, is also regulated by miR-200b. Thus, miR-200b targets GATA-4 to downregulate the expression of cyclin D1 and myosin heavy chain (MHC), thereby regulating cell growth and differentiation.


Assuntos
Ciclo Celular/genética , Fator de Transcrição GATA4/genética , Regulação da Expressão Gênica , MicroRNAs/metabolismo , Animais , Apoptose/genética , Ciclo Celular/fisiologia , Pontos de Checagem do Ciclo Celular/genética , Diferenciação Celular/genética , Diferenciação Celular/fisiologia , Linhagem Celular , Linhagem Celular Tumoral , Proliferação de Células , Ciclina D1/genética , Ciclina D1/metabolismo , Fator de Transcrição GATA4/metabolismo , Humanos , Camundongos , MicroRNAs/genética , Desenvolvimento Muscular/genética , Miócitos Cardíacos/metabolismo , Cadeias Pesadas de Miosina/genética , Cadeias Pesadas de Miosina/metabolismo
14.
Basic Clin Pharmacol Toxicol ; 109(6): 452-6, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21711451

RESUMO

Doxorubicin (Dox) has widely been used as an anticancer drug, but its use is limited by serious toxicity to the heart, kidney and liver. Mitochondrial dysfunction is one of the potential mechanisms of toxicity but not fully understood. Fenofibrate, one of the peroxisome proliferator-activated receptor-alpha (PPARα) ligands, is involved in lipid metabolism which takes place primarily in the mitochondria, so mitochondrial function may be affected by fenofibrate. Therefore, we investigated the effects of DOX and fenofibrate on activities of both mitochondrial citrate synthase and NADH oxidase, which are marker enzymes in the tricarboxylic acid (TCA) cycle and a measure of the complex I-III-IV activity in electron transport chain, respectively. Dox (15 mg/kg) and/or fenofibrate (100 mg/kg/day) were administered to mice for 3 or 14 days, and the activities of citrate synthase and NADH oxidase were measured. Our study showed that Dox significantly inhibits the activity of citrate synthase while fenofibrate induces the activity. Similar to citrate synthase, NADH oxidase activity was also induced by fenofibrate except in spleen but inhibited by Dox except in the heart and liver. Furthermore, fenofibrate not only protects citrate synthase activity from Dox-induced toxicity in the ventricle but also significantly rescues NADH oxidase activity in the kidney. These results reveal the actions of fenofibrate and Dox on the mitochondria, and the underlying mechanism may be related to the toxicity of Dox, which has clinical implications in the side effects of Dox treatment by modulation of mitochondrial function.


Assuntos
Antibióticos Antineoplásicos/toxicidade , Citrato (si)-Sintase/metabolismo , Doxorrubicina/toxicidade , Fenofibrato/farmacologia , Complexos Multienzimáticos/metabolismo , NADH NADPH Oxirredutases/metabolismo , Substâncias Protetoras/farmacologia , Animais , Antibióticos Antineoplásicos/administração & dosagem , Citrato (si)-Sintase/antagonistas & inibidores , Ciclo do Ácido Cítrico , Doxorrubicina/administração & dosagem , Fenofibrato/administração & dosagem , Ligantes , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/enzimologia , Complexos Multienzimáticos/antagonistas & inibidores , NADH NADPH Oxirredutases/antagonistas & inibidores , Especificidade de Órgãos , PPAR alfa/metabolismo , Substâncias Protetoras/administração & dosagem
15.
J Environ Qual ; 38(3): 1126-36, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19398510

RESUMO

Soils in the Fuyang valley (Zhejiang province, southeast China) have been contaminated by heavy metals. Since rice (Oryza sativa L.) is the dominant crop in the valley and because of its tendency to accumulate Cd in its grains, assessment of the human health risk resulting from consumption of locally produced rice is needed. In this study, we used a regression model to predict the average Cd content in rice grains for paddy fields. The multiple linear model for log(Cd) content in rice grains with log(HNO(3)-Cd), pH, log(clay), and log(soil organic matter, SOM) as predictors performed much better (R(2)(adj) = 66.1%) than the model with log(CaCl(2)-Cd) as a single predictor (R(2)(adj) = 28.1%). This can be explained by the sensitivity of CaCl(2)-extracted Cd for changes in redox potential and as a result of the drying of the soil samples in the laboratory. Consequently, the multiple linear model was used to predict the average Cd contents in rice grains for paddy fields, and to estimate the probability that the FAO/WHO standard of 0.2 mg kg(-1) will be exceeded. Eleven blocks had a probability smaller than 10% of exceeding this standard (safe blocks). If a lognormal distribution is assumed, 35 blocks had a probability larger than 90% (blocks at risk). Hence, risk reduction measures should be undertaken for the blocks at risk. For 27 blocks the probability was between 10 and 90%. For these blocks the uncertainty should be reduced via improvement of the regression model and/or increasing the number of sample locations within blocks.


Assuntos
Cádmio/análise , Modelos Químicos , Oryza/química , Sementes/química , Solo/análise , China , Contaminação de Alimentos/análise , Modelos Lineares , Análise de Regressão
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