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1.
Environ Sci Technol ; 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695658

RESUMO

Inhalation of fine particulate matter PM2.5-bound arsenic (PM2.5-As) may cause significant cardiovascular damage, due to its high concentration, long transmission range, and good absorption efficiency in organisms. However, both the contribution and the effect of the arsenic exposure pathway, with PM2.5 as the medium, on cardiovascular system damage in nonferrous smelting sites remain to be studied. In this work, a one-year site sample collection and analysis work showed that the annual concentration of PM2.5-As reached 0.74 µg/m3, which was 120 times the national standard. The predominant species in the PM2.5 samples were As (V) and As (III). A panel study among workers revealed that PM2.5-As exposure dominantly contributed to human absorption of As. After exposure of mice to PM2.5-As for 8 weeks, the accumulation of As in the high exposure group reached equilibrium, and its bioavailability was 24.5%. A series of animal experiments revealed that PM2.5-As exposure induced cardiac injury and dysfunction at the environmental relevant concentration and speciation. By integrating environmental and animal exposure assessments, more accurate health risk assessment models exposed to PM2.5-As were established for metal smelting areas. Therefore, our research provides an important scientific basis for relevant departments to formulate industry supervision, prevention and control policies.

2.
Front Public Health ; 11: 1200722, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37415711

RESUMO

Background: In the context of aging and digitalization, the development and application of digital health can help meet the growing health needs of older adults. Improving digital health literacy of older adults may be an effective way to alleviate the shortage of public health resources and improve their health-related quality of life (HRQoL). However, the impact of digital health literacy on HRQoL in older adults and the underlying mechanism remain unclear. This study intends to explore whether digital health literacy has an effect on HRQoL in community-dwelling older adults, and whether health-promoting lifestyle plays a mediating role between digital health literacy and HRQoL, while providing a theoretical basis for the scientific construction of HRQoL intervention programs for older adults. Methods: The cross-sectional study was conducted in Chongqing, China from September 2020 to April 2021. 572 community-dwelling older adults were surveyed by stratified sampling. Data on sociodemographic characteristics, digital health literacy, health-promoting lifestyle and HRQoL were collected. Univariate analysis was used to compare the differences in HRQoL among community-dwelling older adults with different sociodemographic characteristics. Pearson correlation analysis was used to explore the correlation between digital health literacy, health-promoting lifestyle and HRQoL. SPSS PROCESS macro was used to examine the mediating effect of health-promoting lifestyle between digital health literacy and HRQoL. Results: The mean score of HRQoL was 97.97 (SD 11.45). Univariate analysis showed that there were statistically significant differences in HRQoL among community-dwelling older adults with different gender, age, educational level, marital status, and monthly household income per capita (p < 0.05). There were positive correlations between digital health literacy, health-promoting lifestyle and HRQoL, with correlation coefficients ranging from 0.416 to 0.706 (p < 0.001). Digital health literacy was positively associated with HRQoL (ß = 0.210, p < 0.001), and health-promoting lifestyle mediated the relationship between digital health literacy and HRQoL, with an indirect effect of 0.175 (95% Bootstrap CI 0.135-0.214). Conclusion: Digital health literacy can affect HRQoL through the mediating effect of health-promoting lifestyle. It is suggested that relevant management institutions, communities and families should strengthen the cultivation of the digital health literacy of older adults, promote their development of health-promoting lifestyle, and ultimately improve HRQoL.


Assuntos
Letramento em Saúde , Qualidade de Vida , Humanos , Idoso , Vida Independente , Estudos Transversais , População do Leste Asiático , Estilo de Vida Saudável
3.
Sci Total Environ ; 875: 162615, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36878288

RESUMO

Phthalate esters (PAEs) are one of the significant classes of emerging contaminants that are increasingly detected in environmental and human samples. Nevertheless, the current toxicity studies rarely report how PAEs affect the cardiovascular system, especially in obese individuals. In this study, diet-induced obese mice and corresponding normal mice were exposed to di(2-ethylhexyl) phthalate (DEHP) by oral gavage at environmentally relevant concentrations and key characteristics of cardiovascular risk were examined. The 16S rRNA and high-resolution mass spectrometry were used to investigate the alterations in the gut microbial profile and metabolic homeostasis. The results indicated that the cardiovascular system of fat individuals was more susceptible to DEHP exposure than mice in the lean group. 16S rRNA-based profiling and correlation analysis collectively suggested DEHP-induced gut microbial remodeling in fed a high-fat diet mice, represented by the abundance of the genus Faecalibaculum. Using metagenomic approaches, Faecalibaculum rodentium was identified as the top-ranked candidate bacterium. Additionally, metabolomics data revealed that DEHP exposure altered the gut metabolic homeostasis of arachidonic acid (AA), which is associated with adverse cardiovascular events. Finally, cultures of Faecalibaculum rodentium were treated with AA in vitro to verify the role of Faecalibaculum rodentium in altering AA metabolism. Our findings provide novel insights into DEHP exposure induced cardiovascular damage in obese individuals and suggest that AA could be used as a potential modulator of gut microbiota to prevent related diseases.


Assuntos
Doenças Cardiovasculares , Dietilexilftalato , Microbioma Gastrointestinal , Camundongos , Humanos , Animais , Dietilexilftalato/toxicidade , Dietilexilftalato/metabolismo , Camundongos Obesos , RNA Ribossômico 16S , Ácido Araquidônico , Doenças Cardiovasculares/induzido quimicamente , Fatores de Risco , Obesidade/metabolismo , Fatores de Risco de Doenças Cardíacas
4.
Environ Sci Technol ; 57(4): 1743-1754, 2023 01 31.
Artigo em Inglês | MEDLINE | ID: mdl-36683337

RESUMO

Lead is known to have toxic effects on the cardiovascular system. Owing to its high concentration, transmission range, and absorption efficiency in organisms, inhalation of fine particulate matter (PM2.5)-bound lead (PM2.5-Pb) may cause significant cardiovascular damage. However, the contribution and adverse effects of PM2.5-Pb on workers and residents in non-ferrous metal smelting areas are not fully understood. In this work, the concentration and chemical speciation of PM2.5-Pb were analyzed to determine its pollution characteristics at a typical non-ferrous metal smelting site. A panel study conducted among factory workers revealed that PM2.5-Pb exposure makes an important contribution to the human absorption of Pb. Although the chemical speciation of PM2.5-Pb suggested poor water solubility, a high bioavailability was observed in mice (tissue average value: 50.1%, range: 31.1-71.1%) subjected to inhalation exposure for 8 weeks. Based on the bioavailability data, the relationship between PM2.5-Pb exposure and cardiovascular damage was evaluated in animal simulation experiments. Finally, a damage threshold and cardiovascular-specific risk assessment model were established for the non-ferrous metal smelting area. Our project not only accurately estimates the risk of PM2.5-bound heavy metals on the cardiovascular system but also offers a scientific basis for future prevention and therapy of PM2.5-Pb-related diseases.


Assuntos
Poluentes Atmosféricos , Doenças Cardiovasculares , Metais Pesados , Humanos , Camundongos , Animais , Disponibilidade Biológica , Doenças Cardiovasculares/induzido quimicamente , Doenças Cardiovasculares/epidemiologia , Chumbo , Monitoramento Ambiental , Fatores de Risco , Material Particulado/análise , Medição de Risco , Fatores de Risco de Doenças Cardíacas , China , Poluentes Atmosféricos/análise
6.
J Transl Med ; 20(1): 547, 2022 11 26.
Artigo em Inglês | MEDLINE | ID: mdl-36435781

RESUMO

BACKGROUND: Accumulating evidence supports the implication of circular RNAs (circRNAs) in systemic lupus erythematosus (SLE). However, little is known about the detailed mechanisms and roles of circRNAs in the pathogenesis of SLE. METHODS: Quantitative real-time PCR was used to determine the levels of circLOC101928570 and miR-150-5p in peripheral blood mononuclear cells of SLE. Overexpression and knockdown experiments were conducted to assess the effects of circLOC101928570. Fluorescence in situ hybridization, RNA immunoprecipitation, luciferase reporter assays, Western blot, flow cytometry analysis and enzyme-linked immunosorbent assay were used to investigate the molecular mechanisms underlying the function of circLOC101928570. RESULTS: The results showed that the level of circLOC101928570 was significantly downregulated in SLE and correlated with the systemic lupus erythematosus disease activity index. Functionally, circLOC101928570 acted as a miR-150-5p sponge to relieve the repressive effect on its target c-myb, which modulates the activation of immune inflammatory responses. CircLOC101928570 knockdown enhanced apoptosis. Moreover, circLOC101928570 promoted the transcriptional level of IL2RA by directly regulating the miR-150-5p/c-myb axis. CONCLUSION: Overall, our findings demonstrated that circLOC101928570 played a critical role in SLE. The downregulation of circLOC101928570 suppressed SLE progression through the miR-150-5p/c-myb/IL2RA axis. Our findings identified that circLOC101928570 serves as a potential biomarker for the diagnosis and therapy of SLE.


Assuntos
Lúpus Eritematoso Sistêmico , MicroRNAs , Humanos , RNA Circular/genética , Leucócitos Mononucleares , Hibridização in Situ Fluorescente , Lúpus Eritematoso Sistêmico/genética , MicroRNAs/genética
7.
BMC Nurs ; 21(1): 74, 2022 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-35351123

RESUMO

AIM: To describe the experiences of student nurses in confronting the death of their patients, and to understand how they cope with these events and to what extent there are unmet needs that can be addressed in their trainings. METHODS: Semi-structured interview method was used to collect data from Chinese nursing students and then Colaizzi's seven-step analysis method was applied to identify recurrent themes in their responses to patient deaths. We listened the tape repeatedly combined with observations of their non-verbal behaviors, then transcribed them with emotional resonance, and entered them into Nvivo. After that, we extracted repeated and significant statements from the transcriptions, coded, then clustered codes into sub-themes and themes which were identified by the comparation with transcriptions and re-confirmation with our participants. RESULTS: After confirmation from the interviewees, five themes emerged: emotional experience, challenge, growth, coping and support.

8.
J Trace Elem Med Biol ; 68: 126867, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34592676

RESUMO

OBJECTIVE: This study examined the association between iron status and a set of breast cancer risk factors among U.S. adult women aged 20-80 years. METHODS: Data from National Health and Nutrition Examination Survey (2017-2018) were used to examine the relation between serum ferritin, serum iron and transferrin saturation with a set of breast cancer risk factors [body mass index (BMI), waist circumference, glycosylated hemoglobin (HbA1c), fasting plasma glucose, insulin and HOMA-IR]. The multivariable linear regressions were used controlling for age, race/ethnicity, menopause status, education level, smoking status, alcohol consumption, physical activity, high-sensitivity C-reactive protein (hsCRP) and total energy intake. RESULTS: HbA1c, BMI and waist circumference data were available for 1902 women with a fasting sample (n = 913) for fasting plasma glucose, insulin and HOMA-IR. Transferrin saturation had significant, inverse associations with BMI, waist circumference and HbA1c. The size of difference observed were that participants in the fourth quartile of transferrin saturation had a 4.50 kg/m2 smaller BMI, a 9.36 cm smaller waist circumference and a 0.1 % lower HbA1c level than participants in the first quartile. Similarly, serum iron concentrations were inversely associated with BMI and waist circumference. In addition, serum iron had significant, inverse associations with insulin and HOMA-IR. Sensitivity analyses among men gave similar results. For serum ferritin, there was a trend towards a positive association between waist circumference, HbA1c and fasting plasma glucose with serum ferritin. However, the associations did not reach statistical significance among women. CONCLUSIONS: Iron status may impact breast cancer risk via effects on adiposity or glucose metabolism. The findings should be confirmed with further prospective data.


Assuntos
Neoplasias da Mama , Resistência à Insulina , Adulto , Glicemia , Índice de Massa Corporal , Feminino , Ferritinas , Hemoglobinas Glicadas/metabolismo , Humanos , Insulina , Ferro , Masculino , Inquéritos Nutricionais , Fatores de Risco , Transferrinas , Circunferência da Cintura
9.
Sci Rep ; 11(1): 9374, 2021 04 30.
Artigo em Inglês | MEDLINE | ID: mdl-33931691

RESUMO

Burns are one of the most common injuries in daily life for all ages of population. This study was to investigate the epidemiology and outcomes among burn patients in one of the largest burn centers in the southwest of China. The study was performed at the Institute of Burn Research in the first affiliated with the Army Medical University (AMU). A total of 17,939 burn patients were included in this retrospective study. Information regarding burn epidemiology and outcomes in 17 years were collected, calculated and compared. The age ranged from 257 days to 95 years old. Scalding and flame were the two most common causes to burn injuries, comprising of 91.96% in total. Limbs, head/face/neck, and trunk were the most frequently occurred burn sites, with the number and the percent of 12,324 (68.70%), 7989 (44.53%), and 7771 (43.32%), respectively. The average total body surface area (TBSA) was 13.64 ± 16.83% (median 8%) with a range of 0.1-100%. A total of 874 (4.9%) patients had TBSA > 50%. The presence of a burn with an inhalation injury was confirmed in 543 patients (3.03%). The average LOS was 32.11 ± 65.72 days (median: 17 days). Eventually, the retrospective analysis resulted in the development of a burn management continuum used for developing strategies to prevent and manage severe burns. The annual number of burn injuries has kept decreasing, which was partially attributed to the increased awareness and education of burn prevention and the improved burn-preventative circumstances. However, the burn severity and the economic burden were still in a high level. And the gender difference and age difference should be considered when making individualized interventions and rehabilitative treatments.


Assuntos
Unidades de Queimados/normas , Queimaduras/terapia , Hospitalização/estatística & dados numéricos , Tempo de Internação/estatística & dados numéricos , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Queimaduras/epidemiologia , Criança , Pré-Escolar , China/epidemiologia , Gerenciamento Clínico , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Fatores Sexuais , Adulto Jovem
10.
Front Immunol ; 12: 752736, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35197962

RESUMO

Systemic lupus erythematosus (SLE) is a prototypical systemic autoimmune disease of unknown etiology. The epigenetic regulation of N6-methyladenosine (m6A) modification in immunity is emerging. However, few studies have focused on SLE and m6A immune regulation. In this study, we aimed to explore a potential integrated model of m6A immunity in SLE. The models were constructed based on RNA-seq data of SLE. A consensus clustering algorithm was applied to reveal the m6A-immune signature using principal component analysis (PCA). Univariate and multivariate Cox regression analyses and Kaplan-Meier analysis were used to evaluate diagnostic differences between groups. The effects of m6A immune-related characteristics were investigated, including risk evaluation of m6A immune phenotype-related characteristics, immune cell infiltration profiles, diagnostic value, and enrichment pathways. CIBERSORT, ESTIMATE, and single-sample gene set enrichment analysis (ssGSEA) were used to evaluate the relative immune cell infiltrations (ICIs) of the samples. Conventional bioinformatics methods were used to identify key m6A regulators, pathways, gene modules, and the coexpression network of SLE. In summary, our study revealed that IGFBP3 (as a key m6A regulator) and two pivotal immune genes (CD14 and IDO1) may aid in the diagnosis and treatment of SLE. The potential integrated models of m6A immunity that we developed could guide clinical management and may contribute to the development of personalized immunotherapy strategies.


Assuntos
Biologia Computacional , Lúpus Eritematoso Sistêmico , Adenosina/análogos & derivados , Adenosina/metabolismo , Epigênese Genética , Regulação Neoplásica da Expressão Gênica , Humanos , Lúpus Eritematoso Sistêmico/genética
11.
Transplant Proc ; 52(1): 20-25, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32000939

RESUMO

BACKGROUND: Organ transplantation is an important method to save the lives of patients suffering from organ failure. However, the low rate of organ donation is a common problem worldwide. Many potential organ donors in the intensive care unit (ICU) are not properly identified, which is one reason for the low donation rate. ICU nurses play a key role in organ donation but may be uncertain regarding some issues. In this study, an analysis of the reasons why ICU nurses in western China are reluctant to encourage patients and their families to donate organs is performed, providing a reference for promoting ICU nurse participation in organ donation work. METHODS: From August to November of 2017, using a purposive sampling method, we conducted semi-structured, in-depth interviews using a phenomenological research method with 18 ICU nurses who were working in 4 large hospitals with organ transplant accreditation in Chongqing City, China, and analyzed the data with phenomenology. RESULTS: Reasons for the reluctance of ICU nurses in encouraging patients to donate organs were categorized into the following 4 themes: limitation of the nurses' professional role, influence of the family's negative emotions, lack of training regarding organ donation in medical institutions, and impact of a conservative social attitude. CONCLUSION: Chinese medical and health institutions need to attach importance to the duties and roles of ICU nurses in organ donation work, the creation of a good death culture, the implementation of training for organ donation specialist nurses, and the strengthening of advocacy efforts for organ donation so that ICU nurses' reluctance in engaging in organ donation coordination in China can be mitigated and the nurses can better participate in promoting organ donation to potential donors.


Assuntos
Atitude do Pessoal de Saúde , Papel do Profissional de Enfermagem/psicologia , Recursos Humanos de Enfermagem Hospitalar/psicologia , Transplante de Órgãos/enfermagem , Transplante de Órgãos/psicologia , Adulto , China , Feminino , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa
12.
Front Physiol ; 10: 606, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31191335

RESUMO

Severe burn injury induces intestinal barrier dysfunction; however, the underlying mechanisms remain elusive. Our previous studies have shown that the intestinal epithelial tight junction (TJ) barrier dysfunction is associated with both endoplasmic reticulum (ER) stress and autophagy in severely burned mice, but the precise role of ER stress and autophagy in the burn-induced intestinal TJ barrier dysfunction needs to be determined. In this study, female C57/BL6 mice were assigned randomly to either sham burn or 30% total body surface area (TBSA) full-thickness burn. The effects of ER stress and autophagy on the intestinal epithelial TJ barrier were validated by inducing or inhibiting both ER stress and autophagy in mice treated with sham burn or burn injury. The intestinal permeability, expression, and localization of TJ proteins, ER stress, and autophagy were assessed by physiological, morphological, and biochemical analyses. The results showed that inducing ER stress with tunicamycin or thapsigargin caused the activation of autophagy, the increase of intestinal permeability, as well as the reduction and reorganization of TJ proteins in the sham-burned mice, and aggravated the burn-induced activation of autophagy, increase of intestinal permeability, as well as the reduction and reorganization of TJ proteins. In contrast, inhibiting ER stress with 4-phenylbutyrate alleviated the burn-induced activation of autophagy, increase of intestinal permeability, as well as the reduction and reorganization of TJ proteins. In addition, inducing autophagy with rapamycin resulted in the increase of intestinal permeability, as well as the reduction and reorganization of TJ proteins in the sham-burned mice, and aggravated the burn-induced increase of intestinal permeability as well as the reduction and reorganization of TJ proteins. However, inhibiting autophagy with 3-methyladenine attenuated the burn-induced increase of intestinal permeability, as well as the reduction and reorganization TJ proteins. It is suggested that the ER stress-autophagy axis contributes to the intestinal epithelial TJ barrier dysfunction after severe burn injury.

13.
J Hepatol ; 63(6): 1440-8, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26212029

RESUMO

BACKGROUND & AIMS: Multidrug resistance-associated protein 2 (MRP2) excretes conjugated organic anions including bilirubin and bile acids. Malfunction of MRP2 leads to jaundice in patients. Studies in rodents indicate that Radixin plays a critical role in determining Mrp2 canalicular membrane expression. However, it is not known how human hepatic MRP2 expression is regulated in cholestasis. METHODS: We assessed liver MRP2 expression in patients with obstructive cholestasis caused by gallstone blockage of bile ducts, and investigated the regulatory mechanism in HepG2 cells. RESULTS: Western blot detected that liver MRP2 protein expression in obstructive cholestatic patients (n=30) was significantly reduced to 25% of the non-cholestatic controls (n=23). Immunoprecipitation identified Ezrin but not Radixin associating with MRP2 in human livers, and the increased amount of phospho-Ezrin Thr567 was positively correlated with the amount of co-precipitated MRP2 in cholestatic livers, whereas Ezrin and Radixin total protein levels were unchanged in cholestasis. Further detailed studies indicate that Ezrin Thr567 phosphorylation plays an important role in MRP2 internalization in HepG2 cells. Since increased expression of PKCα, δ and ε were detected in these cholestatic livers, we further confirmed that these PKCs stimulated Ezrin phosphorylation and reduced MRP2 membrane expression in HepG2 cells. Finally, we identified GP78 as the key ubiquitin ligase E3 involved in MRP2 proteasome degradation. CONCLUSIONS: Activation of liver PKCs during cholestasis leads to Ezrin Thr567 phosphorylation resulting in MRP2 internalization and degradation where ubiquitin ligase E3 GP78 is involved. This process provides a mechanistic explanation for jaundice seen in patients with obstructive cholestasis.


Assuntos
Colestase/metabolismo , Proteínas do Citoesqueleto/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Adulto , Canalículos Biliares/metabolismo , Estudos de Casos e Controles , Colestase/etiologia , Colestase/patologia , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/genética , Feminino , Cálculos Biliares/complicações , Técnicas de Silenciamento de Genes , Células Hep G2 , Humanos , Fígado/metabolismo , Fígado/patologia , Masculino , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Pessoa de Meia-Idade , Modelos Biológicos , Proteína 2 Associada à Farmacorresistência Múltipla , Fosforilação , Proteína Quinase C/genética , Proteína Quinase C/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores do Fator Autócrino de Motilidade/antagonistas & inibidores , Receptores do Fator Autócrino de Motilidade/genética , Receptores do Fator Autócrino de Motilidade/metabolismo , Treonina/química
14.
Int J Clin Exp Med ; 8(2): 1691-702, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25932098

RESUMO

BACKGROUND & AIMS: Oleanolic acid is abundantly distributed in Swertia mussotii Franch, a Chinese traditional herb for the treatment of jaundice. However, the hepatoprotective role of oleanolic acid in obstructive cholestasis and its underlying molecular mechanism are unclear. METHODS: Normal rats and bile duct-ligated (BDL) rats were given oleanolic acid and serum biochemistry, bile salts, and pro-inflammatory factors were measured, as well as the expression levels of liver bile acid synthesis and detoxification enzymes, membrane transporters, nuclear receptors, and transcriptional factors. RESULTS: Oral administration of oleanolic acid at 100 mg/kg did not cause rat liver injury. However, it significantly reduced the serum levels of alanine aminotransferase (ALT) on days 7 and 14, aspartate aminotransferase (AST) and TNF-α on day 14, and alkaline phosphatase (ALP) and IL-1ß on days 3, 7, and 14 in the BDL rats. Furthermore, the serum levels of total bile acid (TBA) and bile acids, including CDCA, CA, DCA, and Tα/ßMCA were significantly reduced by oleanolic acid on day 3 in the BDL rats. In addition, the expression levels of detoxification enzymes Cyp3a, Ugt2b, Sult2a1, Gsta1-2, and Gstm1-3, membrane transporters Mrp3, Mrp4, Ostß, Mdr1, Mdr2, and Bsep, nuclear receptors Pxr, Vdr, Hnf4α, Rxrα, Rarα, Lxr, and Lrh-1, and transcriptional factors Nrf2, Hnf3ß, and Ahr were significantly increased in oleanolic acid-treated rats. CONCLUSION: We demonstrated that the oral administration of oleanolic acid attenuates liver injury, inflammation, and cholestasis in BDL rats. The anti-cholestatic effect may be associated with the induction of hepatic detoxification enzymes and efflux transporters mediated by nuclear receptors and transcriptional factors.

15.
PLoS One ; 10(3): e0120055, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25798860

RESUMO

BACKGROUND & AIMS: Levels of bile acid metabolic enzymes and membrane transporters have been reported to change in cholestasis. These alterations (e.g. CYP7A1 repression and MRP4 induction) are thought to be adaptive responses that attenuate cholestatic liver injury. However, the molecular mechanisms of these adaptive responses in human obstructive cholestasis due to gallstone biliary obstruction remain unclear. METHODS: We collected liver samples from cholestatic patients with biliary obstruction due to gallstones and from control patients without liver disease (n = 22 per group). The expression levels of bile acid synthetic and detoxification enzymes, membrane transporters, and the related nuclear receptors and transcriptional factors were measured. RESULTS: The levels of bile acid synthetic enzymes, CYP7B1 and CYP8B1, and the detoxification enzyme CYP2B6 were increased in cholestatic livers by 2.4-fold, 2.8-fold, and 1.9-fold, respectively (p<0.05). Conversely, the expression levels of liver detoxification enzymes, UGT2B4/7, SULT2A1, GSTA1-4, and GSTM1-4, were reduced by approximately 50% (p<0.05) in human obstructive cholestasis. The levels of membrane transporters, OSTß and OCT1, were increased 10.4-fold and 1.8-fold, respectively, (p<0.05), whereas those of OSTα, ABCG2 and ABCG8 were all decreased by approximately 40%, (p<0.05) in human cholestatic livers. Hepatic nuclear receptors, VDR, HNF4α, RXRα and RARα, were induced (approximately 2.0-fold, (p<0.05) whereas FXR levels were markedly reduced to 44% of control, (p<0.05) in human obstructive cholestasis. There was a significantly positive correlation between the reduction in FXR mRNA and UGT2B4/7, SULT2A1, GSTA1, ABCG2/8 mRNA levels in livers of obstructive cholestatic patients (p<0.05). CONCLUSIONS: The levels of hepatic detoxification enzymes were significantly decreased in human obstructive cholestasis, and these decreases were positively associated with a marked reduction of FXR levels. These findings are consistent with impaired detoxification ability in human obstructive cholestasis.


Assuntos
Colestase/enzimologia , Colestase/etiologia , Cálculos Biliares/complicações , Regulação Enzimológica da Expressão Gênica , Fígado/enzimologia , Colestase/genética , Colestase/metabolismo , Humanos , Proteínas de Membrana Transportadoras/genética , Receptores Citoplasmáticos e Nucleares/genética , Fatores de Transcrição/genética , Regulação para Cima
16.
Hepatology ; 55(5): 1485-94, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-22105759

RESUMO

UNLABELLED: Multidrug resistance-associated protein 3 (MRP3, ABC subfamily C [ABCC]3) plays an important role in protecting hepatocytes and other tissues by excreting an array of toxic organic anion conjugates, including bile salts. MRP3/ABCC3 expression is increased in the liver of some cholestatic patients, but the molecular mechanism of this up-regulation remains elusive. In this report, we assessed liver MRP3/ABCC3 expression in patients (n = 22) with obstructive cholestasis caused by gallstone blockage of bile ducts and noncholestatic patient controls (n = 22). MRP3/ABCC3 messenger RNA (mRNA) and protein expression were significantly increased by 3.4- and 4.6-fold, respectively, in these cholestatic patients where elevated plasma tumor necrosis factor alpha (TNFα) (4.7-fold; P < 0.01) and hepatic specificity protein 1 transcription factor (SP1) and liver receptor homolog 1 expression (3.1- and 2.1-fold at mRNA level, 3.5- and 2.5-fold at protein level, respectively) were also observed. The induction of hepatic MRP3/ABCC3 mRNA expression is significantly positively correlated with the level of plasma TNFα in these patients. In HepG2 cells, TNFα treatment induced SP1 and MRP3/ABCC3 expression in a dose- and time-dependent manner, where increased phosphorylation of c-Jun NH2-terminal kinase/stress-activated protein kinase (JNK/SAPK) was also detected. These inductions were significantly reduced in the presence of the JNK inhibitor, SP600125. TNFα treatment enhanced HepG2 cell nuclear extract-binding activity to the MRP3/ABCC3 promoter, but was abolished by SP600125, as demonstrated by electrophoretic mobility shift assay (EMSA). An increase in nuclear protein-binding activity to the MRP3/ABCC3 promoter, consisting primarily of SP1, was also observed in liver samples from cholestatic patients, as assessed by supershift EMSA assays. CONCLUSIONS: Our findings indicate that up-regulation of hepatic MRP3/ABCC3 expression in human obstructive cholestasis is likely triggered by TNFα, mediated by activation of JNK/SAPK and SP1.


Assuntos
Colestase/metabolismo , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Proteínas Associadas à Resistência a Múltiplos Medicamentos/metabolismo , Fator de Transcrição Sp1/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Biópsia por Agulha , Western Blotting , Estudos de Casos e Controles , Colestase/genética , Colestase/patologia , Progressão da Doença , Feminino , Imunofluorescência , Regulação da Expressão Gênica , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/genética , Masculino , Pessoa de Meia-Idade , Proteínas Associadas à Resistência a Múltiplos Medicamentos/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real/métodos , Sensibilidade e Especificidade , Transdução de Sinais , Técnicas de Cultura de Tecidos , Células Tumorais Cultivadas/efeitos dos fármacos , Fator de Necrose Tumoral alfa/sangue , Regulação para Cima
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