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2.
Diabetes Metab Res Rev ; 40(7): e3846, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39329241

RESUMO

Metabolic dysfunction-associated steatohepatitis (MASH), a severe form of metabolic dysfunction-associated steatotic liver disease (MASLD), poses a significant threat to global health. Despite extensive research efforts over the past decade, only one drug has received market approval under accelerated pathways. In this review, we summarise the pathogenesis of MASH and present a comprehensive overview of recent advances in phase 2-3 clinical trials targeting MASH. These trials have highlighted considerable challenges, including low response rates to drugs, limitations of current surrogate histological endpoints, and inadequacies in the design of MASH clinical trials, all of which hinder the progress of MASH pharmacotherapy. We also explored the potential of non-invasive tests to enhance clinical trial design. Furthermore, given the strong association between MASLD and cardiometabolic disorders, we advocate for an integrated approach to disease management to improve overall patient outcomes. Continued investigation into the mechanisms and pharmacology of combination therapies may offer valuable insights for developing innovative MASH treatments.


Assuntos
Doenças Metabólicas , Humanos , Doenças Metabólicas/tratamento farmacológico , Fígado Gorduroso/tratamento farmacológico , Fígado Gorduroso/etiologia , Fígado Gorduroso/metabolismo , Desenvolvimento de Medicamentos , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/etiologia , Síndrome Metabólica/tratamento farmacológico , Síndrome Metabólica/complicações , Ensaios Clínicos como Assunto
3.
Eur J Obstet Gynecol Reprod Biol ; 298: 85-90, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38733778

RESUMO

BACKGROUND: The Mayer-Rokitansky-Küster-Hauser (MRKH) syndrome is a rare condition with significant psychological implications. However, our understanding of its impact on postoperative sexual function and mental health is still limited. AIM: Evaluate the mental health status and sexual functioning of women with MRKH syndrome after vaginoplasty surgery. METHODS: We enrolled 53 cases with MRKH syndrome who underwent artificial vaginoplasty. The participants were asked to participate in a two-round survey conducted between February 2021 during the covid-19 period and March 2023. The survey included questionnaires to measure depression, anxiety, self-esteem, and sexual functioning. Differences between scores over time were analysed using a paired sample t-test, and we assessed the correlation between mental health and sexual functioning. RESULTS: In the first round, patients' mean ± SD age at surgery was 23.6 ± 4.5 years old, and the mean ± SD time that had elapsed since surgery at the time of the survey was 34.2 ± 20.8 months. None of the patients reported low self-esteem, 45.3 % reported mild-to-moderate depression, and 34.0 % reported mild anxiety. Thirty patients have had vaginal intercourse during the last six months. The mean ± SD Female Sexual Functioning Index score was 24.6 ± 4.4, and 60.0 % had a score of 23.5 or higher, indicating high sexual functioning. The sexual functioning scores were positively correlated with self-esteem scores and negatively correlated with depression or anxiety scores (p < 0.05). There was no significant improvement in patient's mental health status and sexual function between the second round survey (71.3 ± 17.8 months after surgery) and the first round survey (p > 0.05). In contrast, the sexual arousal of FSFI were significantly higher in the second survey round (p < 0.05). CONCLUSION: Most patients undergoing vaginoplasty reported persisting mental health challenges. However, the majority reported good sexual functioning.


Assuntos
Transtornos 46, XX do Desenvolvimento Sexual , Ansiedade , Anormalidades Congênitas , Depressão , Ductos Paramesonéfricos , Autoimagem , Vagina , Humanos , Feminino , Transtornos 46, XX do Desenvolvimento Sexual/cirurgia , Transtornos 46, XX do Desenvolvimento Sexual/psicologia , Vagina/cirurgia , Vagina/anormalidades , Ductos Paramesonéfricos/anormalidades , Ductos Paramesonéfricos/cirurgia , Anormalidades Congênitas/cirurgia , Anormalidades Congênitas/psicologia , Adulto , Depressão/psicologia , Depressão/etiologia , Ansiedade/psicologia , Ansiedade/etiologia , Adulto Jovem , Comportamento Sexual/psicologia , Adolescente , COVID-19/psicologia
5.
Arch Toxicol ; 97(7): 1979-1995, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37202523

RESUMO

The role of non-parenchymal cells (NPCs) in the early phase of acetaminophen (APAP)-induced liver injury (AILI) remains unclear. Therefore, single-cell sequencing (scRNA-seq) was performed to explore the heterogeneity and immune network of NPCs in the livers of mice with AILI. Mice were challenged with saline, 300 mg/kg APAP, or 750 mg/kg APAP (n = 3 for each group). After 3 h, the liver samples were collected, digested, and subjected to scRNA-seq. Immunohistochemistry and immunofluorescence were performed to confirm the expression of Makorin ring finger protein 1 (Mkrn1). We identified 14 distinct cell subtypes among the 120,599 cells. A variety of NPCs were involved, even in the early stages of AILI, indicating highly heterogeneous transcriptome dynamics. Cholangiocyte cluster 3, which had high deleted in malignant brain tumors 1 (Dmbt1) expression, was found to perform drug metabolism and detoxification functions. Liver sinusoidal endothelial cells exhibited fenestrae loss and angiogenesis. Macrophage cluster 1 displayed a M1 polarization phenotype, whereas cluster 3 tended to exhibit M2 polarization. Kupffer cells (KCs) exhibited pro-inflammatory effects due to the high expression of Cxcl2. qRT-PCR and western blotting verified that the LIFR-OSM axis might promote the activation of MAPK signaling pathway in RAW264.7 macrophages. Mkrn1 was highly expressed in the liver macrophages of AILI mice and AILI patients. Interaction patterns between macrophages/KCs and other NPCs were complex and diverse. NPCs were highly heterogeneous and were involved in the immune network during the early phase of AILI. In addition, we propose that Mkrn1 may serve as a potential biomarker of AILI.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Doença Hepática Induzida por Substâncias e Drogas , Animais , Camundongos , Acetaminofen/metabolismo , Células Endoteliais , Fígado , Análise de Sequência de RNA , Doença Hepática Induzida por Substâncias e Drogas/genética , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Camundongos Endogâmicos C57BL
9.
Int J Biol Sci ; 18(9): 3800-3817, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35813467

RESUMO

Background : Acetaminophen (APAP)-induced liver injury (AILI) is a common cause of drug-induced liver injury (DILI). The mechanism underlying protection in AILI or DILI remains to be elucidated, and the role of early growth response 1 (Egr1) in AILI and potential mechanisms remain to be known. Methods : The role of Egr1 was studied both in vivo and in vitro. Liver-specific Egr1-knockout (Egr1LKO) mice and those overexpressing Egr1 via tail vein injection of Egr1-expressing adenovirus (Ad-Egr1) were utilized with AILI. Chromatin immunoprecipitation-sequencing, RNA-sequencing, seahorse XF analysis, and targeted fatty acid analysis were performed. EGR1 levels were also studied in liver tissues and serum samples from AILI/DILI patients. Results: In this study, we have demonstrated that Egr1 was upregulated in AILI models in vivo and in vitro. liver-specific Egr1 knockout aggravated AILI; however, Ad-Egr1 treatment ameliorated this. Mechanistically, Egr1 deficiency inhibited, whereas overexpression promoted, mitochondrial respiratory function and fatty acid ß-oxidation (FAO) activity in AILI. Egr1 transcriptionally upregulated FAO-related genes in hepatocytes. Notably, the knockdown of acetyl-coenzyme A acyltransferase 2 (Acaa2), a key gene involved in FAO, diminished this protective effect of Egr1. Clinically, EGR1 was markedly increased in liver tissues from AILI patients. Interestingly, EGR1 levels of liver tissues and serum samples were also obviously higher in idiosyncratic DILI patients. Conclusions: Egr1 confers adaptive protection in AILI, mediated via the transcriptional upregulation of Acaa2, which improves mitochondrial FAO, and might be a potential biomarker and novel therapeutic target for AILI.


Assuntos
Acetaminofen , Doença Hepática Induzida por Substâncias e Drogas , Acetaminofen/toxicidade , Acetil-CoA C-Aciltransferase , Aciltransferases/farmacologia , Animais , Doença Hepática Induzida por Substâncias e Drogas/genética , Proteína 1 de Resposta de Crescimento Precoce/genética , Proteína 1 de Resposta de Crescimento Precoce/farmacologia , Ácidos Graxos , Fígado , Camundongos , Camundongos Endogâmicos C57BL
10.
Cell Biol Toxicol ; 38(3): 505-530, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34401974

RESUMO

Acetaminophen (APAP) overdose is a common cause of drug-induced liver injury (DILI). Ferroptosis has been recently implicated in APAP-induced liver injury (AILI). However, the functional role and underlying mechanisms of mitochondria in APAP-induced ferroptosis are unclear. In this study, the voltage-dependent anion channel (VDAC) oligomerization inhibitor VBIT-12 and ferroptosis inhibitors were injected via tail vein in APAP-injured mice. Targeted metabolomics and untargeted lipidomic analyses were utilized to explore underlying mechanisms of APAP-induced mitochondrial dysfunction and subsequent ferroptosis. As a result, APAP overdose led to characteristic changes generally observed in ferroptosis. The use of ferroptosis inhibitor ferrostatin-1 (or UAMC3203) and iron chelator deferoxamine further confirmed that ferroptosis was responsible for AILI. Mitochondrial dysfunction, which is associated with the tricarboxylic acid cycle and fatty acid ß-oxidation suppression, may drive APAP-induced ferroptosis in hepatocytes. APAP overdose induced VDAC1 oligomerization in hepatocytes, and protecting mitochondria via VBIT-12 alleviated APAP-induced ferroptosis. Ceramide and cardiolipin levels were increased via UAMC3203 or VBIT-12 in APAP-induced ferroptosis in hepatocytes. Knockdown of Smpd1 and Taz expression responsible for ceramide and cardiolipin synthesis, respectively, aggravated APAP-induced mitochondrial dysfunction and ferroptosis in hepatocytes, whereas Taz overexpression protected against these processes. By immunohistochemical staining, we found that levels of 4-hydroxynonenal (4-HNE) protein adducts were increased in the liver biopsy samples of patients with DILI compared to that in those of patients with autoimmune liver disease, chronic viral hepatitis B, and non-alcoholic fatty liver disease (NAFLD). In summary, protecting mitochondria via inhibiting VDAC1 oligomerization attenuated hepatocyte ferroptosis by restoring ceramide and cardiolipin content in AILI.


Assuntos
Analgésicos não Narcóticos , Doença Hepática Induzida por Substâncias e Drogas , Ferroptose , Canal de Ânion 1 Dependente de Voltagem/metabolismo , Acetaminofen/efeitos adversos , Analgésicos não Narcóticos/metabolismo , Animais , Cardiolipinas/metabolismo , Ceramidas/metabolismo , Doença Hepática Induzida por Substâncias e Drogas/metabolismo , Hepatócitos/metabolismo , Humanos , Fígado/patologia , Camundongos , Camundongos Endogâmicos C57BL , Mitocôndrias/metabolismo
11.
Cancer Med ; 9(16): 5908-5921, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32628356

RESUMO

OBJECTIVE: To compare survival outcomes of minimally invasive surgery (MIS) and laparotomy in early-stage cervical cancer (CC) patients. METHODS: A multicenter retrospective cohort study was conducted with International Federation of Gynecology and Obstetrics (FIGO, 2009) stage IA1 (lymphovascular invasion)-IIA1 CC patients undergoing MIS or laparotomy at four tertiary hospitals from 2006 to 2017. Propensity score matching and weighting and multivariate Cox regression analyses were performed. Survival was compared in various matched cohorts and subgroups. RESULTS: Three thousand two hundred and fifty-two patients (2439 MIS and 813 laparotomy) were included after matching. (1) The 2- and 5-year recurrence-free survival (RFS) (2-year, hazard ratio [HR], 1.81;95% confidence interval [CI], 1.09-3.0; 5-year, HR, 2.17; 95% CI, 1.21-3.89) or overall survival (OS) (2-year, HR, 1.87; 95% CI, 1.03-3.40; 5-year, HR, 2.57; 95% CI, 1.29-5.10) were significantly worse for MIS in patients with stage I B1, but not the cohort overall (2-year RFS, HR, 1.04; 95% CI, 0.76-1.42; 2-year OS, HR, 0.99; 95% CI, 0.70-1.41; 5-year RFS, HR, 1.12; 95% CI, 0.76-1.65; 5-year OS, HR, 1.20; 95% CI, 0.79-1.83) or other stages (2) In a subgroup analysis, MIS exhibited poorer survival in many population subsets, even in patients with less risk factors, such as patients with squamous cell carcinoma, negative for parametrial involvement, with negative surgical margins, negative for lymph node metastasis, and deep stromal invasion < 2/3. (3) In the cohort treated with (2172, 54%) or without adjuvant treatment (1814, 46%), MIS showed worse RFS than laparotomy in patients treated without adjuvant treatment, whereas no differences in RFS and OS were observed in adjuvant-treatment cohort. (4) Inadequate surgeon proficiency strongly correlated with poor RFS and OS in patients receiving MIS compared with laparotomy. CONCLUSIONS: MIS exhibited poorer survival outcomes than laparotomy group in many population subsets, even in low-risk subgroups. Therefore, laparotomy should be the recommended approach for CC patients.


Assuntos
Histerectomia/mortalidade , Neoplasias do Colo do Útero/mortalidade , Carcinoma de Células Escamosas/mortalidade , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , China , Competência Clínica , Intervalos de Confiança , Intervalo Livre de Doença , Feminino , Humanos , Histerectomia/métodos , Laparotomia/mortalidade , Laparotomia/estatística & dados numéricos , Metástase Linfática , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos/mortalidade , Procedimentos Cirúrgicos Minimamente Invasivos/estatística & dados numéricos , Pontuação de Propensão , Análise de Regressão , Estudos Retrospectivos , Cirurgiões/normas , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/cirurgia
12.
Future Oncol ; 14(25): 2615-2625, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29882679

RESUMO

AIM: To assess the prognostic value of RAMP3 expression in terms of overall survival (OS) and recurrence-free survival (RFS) in hepatocellular carcinoma (HCC) patients. MATERIALS & METHODS: Immunochemistry staining was performed to detect RAMP3 expression. Data in the Cancer Genome Atlas-Liver Hepatocellular Cancer were used for secondary analysis. RESULTS: RAMP3 expression was significantly downregulated in HCC tissues than in normal liver tissues. Increased RAMP3 expression was an independent prognostic factor of favorable OS (hazard ratio [HR]: 0.772, 95% CI: 0.689-0.864; p < 0.001) and RFS (HR = 0.719, 95% CI: 0.633-0.817; p < 0.001). High RAMP3 expression was associated with significantly better RFS in both TP53 mutant and wildtype groups. CONCLUSION: High RAMP3 RNA expression is an independent prognostic factor of favorable OS and RFS in patients with HCC.


Assuntos
Carcinoma Hepatocelular/mortalidade , Neoplasias Hepáticas/mortalidade , Mutação , Proteína 3 Modificadora da Atividade de Receptores/fisiologia , Proteína Supressora de Tumor p53/genética , Adulto , Idoso , Carcinoma Hepatocelular/química , Carcinoma Hepatocelular/genética , Metilação de DNA , Feminino , Humanos , Fígado/química , Neoplasias Hepáticas/química , Neoplasias Hepáticas/genética , Masculino , Pessoa de Meia-Idade , Prognóstico , Proteína 3 Modificadora da Atividade de Receptores/análise , Proteína 3 Modificadora da Atividade de Receptores/genética
13.
Toxicol Lett ; 283: 69-76, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29174983

RESUMO

Acetaminophen (APAP) overdose is a leading cause of drug-induced acute liver failure in many countries. In the present study, we developed stable mouse models of acute drug-induced hepatic injury (DILI) and acute drug-induced hepatic failure (DILF) by sub-lethal and lethal APAP injection respectively. The differences in hepatic transcriptome profiling between these two models were compared by RNA sequencing, which were validated by qPCR, western-blot and ELISA. In results, serum IL-6, TNF-a and IL-10 levels are higher in DILF than in DILI. The upregulated genes in DILF compared with DILI were mostly enriched in the areas of "cellular development process", "cell division", "multicellular organism development," etc. The downregulated genes in DILF compared with DILI were mostly enriched in the areas of "cellular response to chemical stimulus", "cellular response to stress", "cell activation," etc. Sub-lethal doses of APAP increased Myc, Bag3 and Btc expression in mouse liver, but lethal doses of APAP did not, which suggested that these three genes might play important roles in adaptive protection reactions in DILI. The serum Btc level might be a potential biomarker of drug induced liver injury with good prognosis. Our data can help us better understand the mechanisms of hepatotoxicity that influence prognosis and seek novel prognostic indicators of DILI.


Assuntos
Acetaminofen/toxicidade , Analgésicos não Narcóticos/toxicidade , Doença Hepática Induzida por Substâncias e Drogas/genética , Falência Hepática Aguda/induzido quimicamente , Falência Hepática Aguda/genética , Transcriptoma/efeitos dos fármacos , Animais , Biomarcadores , Perfilação da Expressão Gênica , Regulação da Expressão Gênica/efeitos dos fármacos , Interleucina-10/biossíntese , Interleucina-10/genética , Interleucina-6/biossíntese , Interleucina-6/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fator de Necrose Tumoral alfa/biossíntese , Fator de Necrose Tumoral alfa/genética
14.
World J Hepatol ; 9(4): 191-208, 2017 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-28217257

RESUMO

AIM: To uncover the role of hepatocyte nuclear factor 4 alpha (HNF4α) in regulating hepatic expression of microRNAs. METHODS: Microarray and real-time PCR were used to determine hepatic expression of microRNAs in young-adult mice lacking Hnf4α expression in liver (Hnf4α-LivKO). Integrative genomics viewer software was used to analyze the public chromatin immunoprecipitation-sequencing datasets for DNA-binding of HNF4α, RNA polymerase-II, and histone modifications to loci of microRNAs in mouse liver and human hepatoma cells. Dual-luciferase reporter assay was conducted to determine effects of HNF4α on the promoters of mouse and human microRNAs as well as effects of microRNAs on the untranslated regions (3'UTR) of two genes in human hepatoma cells. RESULTS: Microarray data indicated that most microRNAs remained unaltered by Hnf4α deficiency in Hnf4α-LivKO mice. However, certain liver-predominant microRNAs were down-regulated similarly in young-adult male and female Hnf4α-LivKO mice. The down-regulation of miR-101, miR-192, miR-193a, miR-194, miR-215, miR-802, and miR-122 as well as induction of miR-34 and miR-29 in male Hnf4α-LivKO mice were confirmed by real-time PCR. Analysis of public chromatin immunoprecipitation-sequencing data indicates that HNF4α directly binds to the promoters of miR-101, miR-122, miR-194-2/miR-192 and miR-193, which is associated with histone marks of active transcription. Luciferase reporter assay showed that HNF4α markedly activated the promoters of mouse and human miR-101b/miR-101-2 and the miR-194/miR-192 cluster. Additionally, miR-192 and miR-194 significantly decreased activities of luciferase reporters for the 3'UTR of histone H3F3 and chromodomain helicase DNA binding protein 1 (CHD1), respectively, suggesting that miR-192 and miR-194 might be important in chromosome remodeling through directly targeting H3F3 and CHD1. CONCLUSION: HNF4α is essential for hepatic basal expression of a group of liver-enriched microRNAs, including miR-101, miR-192, miR-193a, miR-194 and miR-802, through which HNF4α may play a major role in the post-transcriptional regulation of gene expression and maintenance of the epigenome in liver.

15.
BMC Gastroenterol ; 15: 94, 2015 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-26219821

RESUMO

BACKGROUND: The NF-kB signaling, regulated by IKK1-p52/RelB and IKK2-p65, is activated by various stresses to protect or damage the liver, in context-specific manners. Two previous studies of liver-specific expression of constitutive active IKK2 (IKK2ca) showed that strong activation of IKK2-NF-kB in mouse livers caused inflammation, insulin resistance, and/or fibrosis. The purpose of this study was to understand how moderate activation of IKK2-NF-kB in adult mouse livers alters hepatic gene expression and pathophysiology. METHOD: We generated mice with adult hepatocyte-specific activation of Ikk2 (Liv-Ikk2ca) using Alb-cre mice and Ikk2ca Rosa26 knockin mice in which a moderate expression of Ikk2ca transgene was driven by the endogenous Rosa26 promoter. RESULTS: Surprisingly, compared to wild-type mice, adult male Liv-Ikk2ca mice had higher hepatic mRNA expression of Ikk2 and classical NF-kB targets (e.g. Lcn2 and A20), as well as IKK1, NIK, and RelB, but no changes in markers of inflammation or fibrosis. Blood levels of IL-6 and MCP-1 remained unchanged, and histology analysis showed a lack of injury or infiltration of inflammatory cells in livers of Liv-Ikk2ca mice. Moreover, Liv-Ikk2ca mice had lower mRNA expression of prooxidative enzymes Cyp2e1 and Cyp4a14, higher expression of antioxidative enzymes Sod2, Gpx1, and Nqo1, without changes in key enzymes for fatty acid oxidation, glucose utilization, or gluconeogenesis. In parallel, Liv-Ikk2ca mice and wild-type mice had similar levels of hepatic reduced glutathione, endogenous reactive oxygen species, and lipid peroxidation. Additionally, Liv-Ikk2ca mice had higher Cyp3a11 without down-regulation of most drug processing genes. Regarding nuclear proteins of NF-kB subunits, Liv-Ikk2ca mice had moderately higher p65 and p50 but much higher RelB. Results of ChIP-qPCR showed that the binding of p50 to multiple NF-kB-target genes was markedly increased in Liv-Ikk2ca mice. Additionally, Liv-Ikk2ca mice had moderate increase in triglycerides in liver, which was associated with higher lipogenic factors Pparγ, Lxr, Fasn, Scd1, and CD36. CONCLUSION: In summary, moderate activation of IKK2-NF-kB in unstressed adult mouse hepatocytes produces a cytoprotective gene expression profile and induces lipogenesis without apparent signs of inflammation or fibrosis, likely due to strong activation of the anti-inflammatory IKK1-RelB alternative NF-kB pathway as well as the Lxr.


Assuntos
Citoproteção/genética , Hepatócitos/metabolismo , Quinase I-kappa B/metabolismo , Fígado/metabolismo , NF-kappa B/metabolismo , Animais , Quimiocina CCL2/sangue , Citocromo P-450 CYP2E1/genética , Citocromo P-450 CYP3A/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Família 4 do Citocromo P450 , Fibrose/metabolismo , Expressão Gênica , Inflamação , Interleucina-6/sangue , Lipogênese , Masculino , Proteínas de Membrana/metabolismo , Camundongos , RNA Mensageiro/metabolismo , Fator de Transcrição RelB/metabolismo , Triglicerídeos/metabolismo
16.
Toxicol Sci ; 141(2): 538-46, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25055961

RESUMO

Bile acids (BAs) are known to regulate their own homeostasis, but the potency of individual bile acids is not known. This study examined the effects of cholic acid (CA), chenodeoxycholic acid (CDCA), deoxycholic acid (DCA), lithocholic acid (LCA) and ursodeoxycholic acid (UDCA) on expression of BA synthesis and transport genes in human primary hepatocyte cultures. Hepatocytes were treated with the individual BAs at 10, 30, and 100µM for 48 h, and RNA was extracted for real-time PCR analysis. For the classic pathway of BA synthesis, BAs except for UDCA markedly suppressed CYP7A1 (70-95%), the rate-limiting enzyme of bile acid synthesis, but only moderately (35%) down-regulated CYP8B1 at a high concentration of 100µM. BAs had minimal effects on mRNA of two enzymes of the alternative pathway of BA synthesis, namely CYP27A1 and CYP7B1. BAs increased the two major target genes of the farnesoid X receptor (FXR), namely the small heterodimer partner (SHP) by fourfold, and markedly induced fibroblast growth factor 19 (FGF19) over 100-fold. The BA uptake transporter Na(+)-taurocholate co-transporting polypeptide was unaffected, whereas the efflux transporter bile salt export pump was increased 15-fold and OSTα/ß were increased 10-100-fold by BAs. The expression of the organic anion transporting polypeptide 1B3 (OATP1B3; sixfold), ATP-binding cassette (ABC) transporter G5 (ABCG5; sixfold), multidrug associated protein-2 (MRP2; twofold), and MRP3 (threefold) were also increased, albeit to lesser degrees. In general, CDCA was the most potent and effective BA in regulating these genes important for BA homeostasis, whereas DCA and CA were intermediate, LCA the least, and UDCA ineffective.


Assuntos
Ácidos e Sais Biliares/biossíntese , Hepatócitos/metabolismo , Proteínas de Membrana Transportadoras/metabolismo , Ácidos e Sais Biliares/farmacologia , Células Cultivadas , Análise por Conglomerados , Relação Dose-Resposta a Droga , Regulação da Expressão Gênica , Hepatócitos/efeitos dos fármacos , Homeostase , Humanos , Proteínas de Membrana Transportadoras/efeitos dos fármacos , Proteínas de Membrana Transportadoras/genética , Cultura Primária de Células , RNA Mensageiro/metabolismo , Fatores de Tempo
17.
Toxicol Sci ; 103(1): 35-45, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18296417

RESUMO

The liver-specific importer organic anion transporting polypeptide 1b2 (Oatp1b2, Slco1b2, also known as Oatp4 and Lst-1) and its human orthologs OATP1B1/1B3 transport a large variety of chemicals. Oatp1b2-null mice were engineered by homologous recombination and their phenotype was characterized. Oatp1b2 protein was absent in livers of Oatp1b2-null mice. Oatp1b2-null mice develop normally and breed well. However, adult Oatp1b2-null mice had moderate conjugated hyperbilirubinemia. Compared with wild-types, Oatp1b2-null mice had similar hepatic messenger RNA expression of most transporters examined except a higher Oatp1a4 but lower organic anion transporter 2. Intra-arterial injection of the mushroom toxin phalloidin (an Oatp1b2-specific substrate identified in vitro) caused cholestasis in wild-type mice but not in Oatp1b2-null mice. Hepatic uptake of fluorescence-labeled phalloidin was absent in Oatp1b2-null mice. Three hours after administration of microcystin-LR (a blue-green algae toxin), the binding of microcystin-LR to hepatic protein phosphatase 1/2a was much lower in Oatp1b2-null mice compared with wild-type mice. In contrast, Oatp1b2-null mice were transiently protected from decrease in bile flow induced by estradiol-17beta-D-glucuronide, a common substrate for Oatps. Oatp1b2-null mice were completely resistant to the hepatotoxicity induced by phalloidin and microcystin-LR, but were similarly sensitive to alpha-amanitin-induced hepatotoxicity compared with wild-type mice. In conclusion, Oatp1b2-null mice display altered basic physiology and markedly decreased hepatic uptake/toxicity of phalloidin and microcystin-LR. Oatp1b2-null mice are useful in elucidating the role of Oatp1b2 and its human orthologs OATP1B1/1B3 in hepatic uptake and systemic disposition of toxic chemicals and therapeutic drugs.


Assuntos
Fígado/metabolismo , Microcistinas/farmacocinética , Microcistinas/toxicidade , Transportadores de Ânions Orgânicos/fisiologia , Faloidina/farmacocinética , Faloidina/toxicidade , Sequência de Aminoácidos , Animais , Sequência de Bases , Bile/metabolismo , Primers do DNA , Fígado/efeitos dos fármacos , Masculino , Toxinas Marinhas , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Dados de Sequência Molecular , Transportadores de Ânions Orgânicos/química , Transportadores de Ânions Orgânicos/genética , Reação em Cadeia da Polimerase
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