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1.
Kidney Int ; 101(2): 349-359, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34560138

RESUMO

Amyloid A amyloidosis is a serious clinical condition resulting from the systemic deposition of amyloid A originating from serum amyloid A proteins with the kidneys being the most commonly and earliest affected organ. Previously described amyloid A amyloidosis is linked to increased production and deposition of serum amyloid A proteins secondary to inflammatory conditions arising from infectious, metabolic, or genetic causes. Here we describe a family with primary amyloid A amyloidosis due to a chr11:18287683 T>C (human genome version19) mutation in the SAA1 promoter linked to the amyloidogenic SAA1.1 haplotype. This condition leads to a doubling of the basal SAA1 promoter activity and sustained elevation of serum amyloid A levels that segregated in an autosomal dominant pattern in 12 genetically affected and in none of six genetically unaffected relatives, yielding a statistically significant logarithm of odds (LOD) score over 5. Affected individuals developed proteinuria, chronic kidney disease and systemic deposition of amyloid composed specifically of the SAA1.1 isoform. Tocilizumab (a monoclonal antibody against the interleukin-6 receptor) had a beneficial effect when prescribed early in the disease course. Idiopathic forms represent a significant and increasing proportion (15-20%) of all diagnosed cases of amyloid A amyloidosis. Thus, genetic screening of the SAA1 promoter should be pursued in individuals with amyloid A amyloidosis and no systemic inflammation, especially if there is a positive family history.


Assuntos
Amiloidose , Amiloidose/complicações , Humanos , Mutação , Regiões Promotoras Genéticas , Proteína Amiloide A Sérica/genética , Proteína Amiloide A Sérica/metabolismo
2.
Cell Mol Life Sci ; 77(14): 2815-2838, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31583425

RESUMO

Biological effects of high fluence low-power (HFLP) lasers have been reported for some time, yet the molecular mechanisms procuring cellular responses remain obscure. A better understanding of the effects of HFLP lasers on living cells will be instrumental for the development of new experimental and therapeutic strategies. Therefore, we investigated sub-cellular mechanisms involved in the laser interaction with human hepatic cell lines. We show that mitochondria serve as sub-cellular "sensor" and "effector" of laser light non-specific interactions with cells. We demonstrated that despite blue and red laser irradiation results in similar apoptotic death, cellular signaling and kinetic of biochemical responses are distinct. Based on our data, we concluded that blue laser irradiation inhibited cytochrome c oxidase activity in electron transport chain of mitochondria. Contrary, red laser triggered cytochrome c oxidase excessive activation. Moreover, we showed that Bcl-2 protein inhibited laser-induced toxicity by stabilizing mitochondria membrane potential. Thus, cells that either overexpress or have elevated levels of Bcl-2 are protected from laser-induced cytotoxicity. Our findings reveal the mechanism how HFLP laser irradiation interfere with cell homeostasis and underscore that such laser irradiation permits remote control of mitochondrial function in the absence of chemical or biological agents.


Assuntos
Complexo IV da Cadeia de Transporte de Elétrons/genética , Transporte de Elétrons/efeitos da radiação , Terapia com Luz de Baixa Intensidade , Fototerapia , Apoptose/efeitos da radiação , Sobrevivência Celular/genética , Sobrevivência Celular/efeitos da radiação , Transporte de Elétrons/genética , Regulação da Expressão Gênica/efeitos da radiação , Células Hep G2 , Humanos , Potencial da Membrana Mitocondrial/genética , Potencial da Membrana Mitocondrial/efeitos da radiação , Mitocôndrias/genética , Mitocôndrias/efeitos da radiação , Membranas Mitocondriais/metabolismo , Membranas Mitocondriais/efeitos da radiação , Oxirredução/efeitos da radiação , Espécies Reativas de Oxigênio/metabolismo
3.
Int J Mol Sci ; 22(5)2021 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-33806448

RESUMO

Lambda interferons mediate antiviral immunity by inducing interferon-stimulated genes (ISGs) in epithelial tissues. A common variant rs368234815TT/∆G creating functional gene from an IFNL4 pseudogene is associated with the expression of major ISGs in the liver but impaired clearance of hepatitis C. To explain this, we compared Halo-tagged and non-tagged IFNL3 and IFNL4 signaling in liver-derived cell lines. Transfection with non-tagged IFNL3, non-tagged IFNL4 and Halo-tagged IFNL4 led to a similar degree of JAK-STAT activation and ISG induction; however, the response to transfection with Halo-tagged IFNL3 was lower and delayed. Transfection with non-tagged IFNL3 or IFNL4 induced no transcriptome change in the cells lacking either IL10R2 or IFNLR1 receptor subunits. Cytosolic overexpression of signal peptide-lacking IFNL3 or IFNL4 in wild type cells did not interfere with JAK-STAT signaling triggered by interferons in the medium. Finally, expression profile changes induced by transfection with non-tagged IFNL3 and IFNL4 were highly similar. These data do not support the hypothesis about IFNL4-specific non-canonical signaling and point out that functional studies conducted with tagged interferons should be interpreted with caution.


Assuntos
Hepatócitos/imunologia , Hepatócitos/metabolismo , Interferons/genética , Interferons/metabolismo , Interleucinas/genética , Interleucinas/metabolismo , Linhagem Celular , Expressão Gênica , Técnicas de Inativação de Genes , Células Hep G2 , Humanos , Fatores Reguladores de Interferon/genética , Fatores Reguladores de Interferon/metabolismo , Interferons/deficiência , Subunidade beta de Receptor de Interleucina-10/deficiência , Subunidade beta de Receptor de Interleucina-10/genética , Subunidade beta de Receptor de Interleucina-10/metabolismo , Interleucinas/deficiência , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores de Interferon/deficiência , Receptores de Interferon/genética , Receptores de Interferon/metabolismo , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Transdução de Sinais , Transfecção
4.
Int J Mol Sci ; 22(19)2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34638908

RESUMO

Heterozygotes for Z or S alleles of alpha-1-antrypsin (AAT) have low serum AAT levels. Our aim was to compare the risk of hepatocellular carcinoma (HCC) in patients with liver cirrhosis carrying the SERPINA1 MM, MZ and MS genotypes. The study groups consisted of 1119 patients with liver cirrhosis of various aetiologies, and 3240 healthy individuals served as population controls. The MZ genotype was significantly more frequent in the study group (55/1119 vs. 87/3240, p < 0.0001). The MS genotype frequency was comparable in controls (32/119 vs. 101/3240, p = 0.84). MZ and MS heterozygotes had lower serum AAT level than MM homozygotes (medians: 0.90 g/L; 1.40 g/L and 1.67 g/L; p < 0.001 for both). There were significantly fewer patients with HCC in the cirrhosis group among MZ and MS heterozygotes than in MM homozygotes (5/55 and 1/32 respectively, vs. 243/1022, p < 0.01 for both). The risk of HCC was lower in MZ and MS heterozygotes than in MM homozygotes (OR 0.3202; 95% CI 0.1361-0.7719 and OR 0.1522; 95% CI 0.02941-0.7882, respectively). Multivariate analysis of HCC risk factors identified MZ or MS genotype carriage as a protective factor, whereas age, male sex, BMI and viral aetiology of cirrhosis increased HCC risk.


Assuntos
Carcinoma Hepatocelular/genética , Cirrose Hepática/genética , Neoplasias Hepáticas/genética , alfa 1-Antitripsina/genética , Alelos , Índice de Massa Corporal , Carcinoma Hepatocelular/complicações , Feminino , Frequência do Gene , Genótipo , Humanos , Cirrose Hepática/complicações , Neoplasias Hepáticas/complicações , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Fatores de Risco , Fatores Sexuais , alfa 1-Antitripsina/sangue
5.
Ann Hepatol ; 19(2): 126-133, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31759867

RESUMO

ATP-binding cassette (ABC) subfamily B member 4 (ABCB4), also known as multidrug resistance protein 3 (MDR3), encoded by ABCB4, is involved in biliary phospholipid secretion, protecting hepatobiliary system from deleterious detergent and lithogenic properties of the bile. ABCB4 mutations altering canalicular ABCB4 protein function and expression may have variable clinical presentation and predispose to several human liver diseases. Well-established phenotypes of ABCB4 deficit are: progressive familial intrahepatic cholestasis type 3, gallbladder disease 1 (syn. low phospholipid associated cholelithiasis syndrome), high ɣ-glutamyl transferase intrahepatic cholestasis of pregnancy, chronic cholangiopathy, and adult biliary fibrosis/cirrhosis. Moreover, ABCB4 aberrations may be involved in some cases of drug induced cholestasis, transient neonatal cholestasis, and parenteral nutrition-associated liver disease. Recently, genome-wide association studies have documented occurrence of malignant tumours, predominantly hepatobiliary malignancies, in patients with ABCB4/MDR3 deficit. The patient's age at the time of the first presentation of cholestatic disease, as well as the severity of liver disorder and response to treatment are related to the ABCB4 allelic status. Mutational analysis of ABCB4 in patients and their families should be considered in all individuals with cholestasis of unknown aetiology, regardless of age and/or time of onset of the first symptoms.


Assuntos
Subfamília B de Transportador de Cassetes de Ligação de ATP/deficiência , Doença Hepática Induzida por Substâncias e Drogas/genética , Colelitíase/genética , Colestase Intra-Hepática/genética , Cirrose Hepática Biliar/genética , Complicações na Gravidez/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Idade de Início , Alelos , Doenças dos Ductos Biliares/genética , Colagogos e Coleréticos/uso terapêutico , Colestase/genética , Doenças da Vesícula Biliar/genética , Humanos , Hepatopatias/etiologia , Hepatopatias/genética , Nutrição Parenteral/efeitos adversos , Ácido Ursodesoxicólico/uso terapêutico
6.
Cell Physiol Biochem ; 52(1): 119-140, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30790509

RESUMO

BACKGROUND/AIMS: Alteration of cancer cell redox status has been recognized as a promising therapeutic implication. In recent years, the emerged field of non-thermal plasma (NTP) has shown considerable promise in various biomedical applications, including cancer therapy. However, understanding the molecular mechanisms procuring cellular responses remains incomplete. Thus, the aim of this study was a rigorous biochemical analysis of interactions between NTP and liver cancer cells. METHODS: The concept was validated using three different cell lines. We provide several distinct lines of evidence to support our findings; we use various methods (epifluorescent and confocal microscopy, clonogenic and cytotoxicity assays, Western blotting, pharmacological inhibition studies, etc.). RESULTS: We assessed the influence of NTP on three human liver cancer cell lines (Huh7, Alexander and HepG2). NTP treatment resulted in higher anti-proliferative effect against Alexander and Huh7 relative to HepG2. Our data clearly showed that the NTP-mediated alternation of mitochondrial membrane potential and dynamics led to ROS-mediated apoptosis in Huh7 and Alexander cells. Interestingly, plasma treatment resulted in p53 down-regulation in Huh7 cells. High levels of Bcl-2 protein expression in HepG2 resulted in their resistance in response to oxidative stress- mediated by plasma. CONCLUSION: We show thoroughly time- and dose-dependent kinetics of ROS accumulation in HCC cells. Furthermore, we show nuclear compartmentalization of the superoxide anion triggered by NTP. NTP induced apoptotic death in Huh7 liver cancer cells via simultaneous downregulation of mutated p53, pSTAT1 and STAT1. Contrary, hydrogen peroxide treatment results in autophagic cell death. We disclosed detailed mechanisms of NTP-mediated alteration of redox signalling in liver cancer cells.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Neoplasias Hepáticas/tratamento farmacológico , Gases em Plasma/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Proteína Supressora de Tumor p53/biossíntese , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/metabolismo , Carcinoma Hepatocelular/patologia , Morte Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/metabolismo , Neoplasias Hepáticas/patologia , Oxirredução/efeitos dos fármacos , Proteína Supressora de Tumor p53/genética
7.
Transpl Infect Dis ; 21(4): e13124, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31165537

RESUMO

BACKGROUND: Cytomegalovirus (CMV) disease represents a serious complication in liver transplant (OLT) recipients. CMV prophylaxis reduces incidence of CMV disease in the early post-transplant period (on-prophylaxis disease, OPD) but may postpone its manifestation after the completion of prophylaxis. Post-prophylaxis disease (PPD) incidence after prophylaxis cessation may be modified by genetic factors. METHODS: We analyzed impact of IL28B rs1297986 variants on CMV disease incidence in 743 adult OLT recipients receiving universal prophylaxis. RESULTS: One hundred and forty-four (19.4%) patients had at least one CMV disease episode. One hundred and two of them (70.8%) had at least one OPD and 36 (25%) patients had PPD, six (4.2%) patients had both. The rate of IL28B T allele carriers was lower in PPD group (38.9%) in comparison with OPD group (66.7%, P = 0.005) and group without CMV disease (61.4%, P = 0.009). The impact of IL28B genotype on the risk of CMV OPD was significant neither in the allelic (TT + CT vs CC, P = 0.32) nor in the recessive model (TT vs CT + CC, P = 0.79). Contrarily, in the PPD group, T allele (TT + CT vs CC) had a protective effect, OR 0.4 (95% CI 0.2-0.8, P = 0.008). Further risk factors of PPD were age <55 years and valganciclovir prophylaxis, whereas the risk factors of OPD were age <55 years, cyclosporine A therapy and pre-transplant CMV serostatus (donor +/recipient -). CONCLUSIONS: IL28B rs12979860 T allele carriers had a lower risk of CMV PPD.


Assuntos
Infecções por Citomegalovirus/genética , Infecções por Citomegalovirus/prevenção & controle , Interferons/genética , Transplante de Fígado , Adulto , Idoso , Alelos , Antivirais/uso terapêutico , Estudos de Coortes , Feminino , Ganciclovir/uso terapêutico , Genótipo , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Doadores de Tecidos , Transplantados , Adulto Jovem
8.
J Pathol ; 241(1): 104-114, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27741349

RESUMO

Iron is both an essential and a potentially toxic element, and its systemic homeostasis is controlled by the iron hormone hepcidin. Hepcidin binds to the cellular iron exporter ferroportin, causes its degradation, and thereby diminishes iron uptake from the intestine and the release of iron from macrophages. Given that hepcidin-resistant ferroportin mutant mice show exocrine pancreas dysfunction, we analysed pancreata of aging hepcidin knockout (KO) mice. Hepcidin and Hfe KO mice were compared with wild-type (WT) mice kept on standard or iron-rich diets. Twelve-month-old hepcidin KO mice were subjected to daily minihepcidin PR73 treatment for 1 week. Six-month-old hepcidin KO mice showed cytoplasmic acinar iron overload and mild pancreatitis, together with elevated expression of the iron uptake mediators DMT1 and Zip14. Acinar atrophy, massive macrophage infiltration, fatty changes and pancreas fibrosis were noted in 1-year-old hepcidin KO mice. As an underlying mechanism, 6-month-old hepcidin KO mice showed increased pancreatic oxidative stress, with elevated DNA damage, apoptosis and activated nuclear factor-κB (NF-κB) signalling. Neither iron overload nor pancreatic damage was observed in WT mice fed iron-rich diet or in Hfe KO mice. Minihepcidin application to hepcidin KO mice led to an improvement in general health status and to iron redistribution from acinar cells to macrophages. It also resulted in decreased NF-κB activation and reduced DNA damage. In conclusion, loss of hepcidin signalling in mice leads to iron overload-induced chronic pancreatitis that is not seen in situations with less severe iron accumulation. The observed tissue injury can be reversed by hepcidin supplementation. Copyright © 2016 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Células Acinares/metabolismo , Hepcidinas/deficiência , Sobrecarga de Ferro/complicações , Pancreatite Crônica/etiologia , Animais , Apoptose/fisiologia , Citoplasma/metabolismo , Modelos Animais de Doenças , Hepcidinas/genética , Hepcidinas/fisiologia , Sobrecarga de Ferro/metabolismo , Sobrecarga de Ferro/patologia , Macrófagos/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microscopia Eletrônica de Transmissão , Estresse Oxidativo/fisiologia , Pâncreas/ultraestrutura , Pancreatite Crônica/metabolismo , Pancreatite Crônica/patologia
9.
Liver Transpl ; 22(5): 644-55, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26707008

RESUMO

Steatosis occurs frequently after liver transplantation (LT). We aimed to determine the prevalence of steatosis in adult LT recipients, to determine the effects of significant (>33%; grades 2-3) steatosis on patient survival, and to identify risk factors for the development of significant steatosis and its effect on fibrosis progression. We retrospectively examined 2360 posttransplant biopsies of 548 LT recipients. Survival was compared between patients with significant steatosis and those with grades 0-1 steatosis. Patients with significant steatosis were compared to controls without steatosis (grade 0) for clinical and laboratory factors and fibrosis progression. Steatosis was found in 309 (56.4%) patients, including 93 (17.0%) patients with significant steatosis. Steatohepatitis (nonalcoholic fatty liver disease activity score ≥ 5) was diagnosed in 57 (10.4%) patients. The prevalence of steatosis increased from 30.3% at 1 year to 47.6% at 10 years after LT (P < 0.001). Survival times did not differ between groups (P = 0.29). On multivariate analysis of pretransplant factors and initial immunosuppression (IS), alcohol-induced cirrhosis (P < 0.001) and high body mass index (BMI; P = 0.002) were associated with the development of significant steatosis, whereas increased levels of alkaline phosphatase (P = 0.01) and mycophenolate mofetil given initially (P = 0.009) appeared to protect against significant steatosis. On multivariate analysis of posttransplant factors, high BMI (P < 0.001), serum triglycerides (P < 0.001), alcohol consumption (P = 0.005), and type 2 diabetes mellitus (P = 0.048) were associated with significant steatosis, whereas high creatinine (P = 0.02) appeared to protect against significant steatosis. Significant steatosis was not associated with a higher fibrosis stage (P = 0.62). Posttransplant steatosis affects 56.4% of LT recipients, and the prevalence increases with time after LT. Recipient factors and types of IS affect the risk for significant steatosis, which is not associated with a higher fibrosis stage or worse patient survival. Liver Transplantation 22 644-655 2016 AASLD.


Assuntos
Transplante de Fígado/efeitos adversos , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/etiologia , Adulto , Consumo de Bebidas Alcoólicas , Fosfatase Alcalina/sangue , Biópsia , Diabetes Mellitus Tipo 2/sangue , Progressão da Doença , Feminino , Humanos , Cirrose Hepática/sangue , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Ácido Micofenólico/administração & dosagem , Prevalência , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento , Triglicerídeos/sangue
10.
Pediatr Int ; 57(5): 981-5, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26508179

RESUMO

A 7-year-old girl had been followed up for persistent conjugated hyperbilirubinemia since birth. Alanine aminotransferase, aspartate aminotransferase and γ-glutamyl transpeptidase activity was within the normal range, and liver protein synthesis had always been normal. Infectious etiology of jaundice, autoimmune diseases, drug-induced liver injury, hemolytic anemia, α-1 anti-trypsin deficiency, Wilson disease and Gilbert syndrome were ruled out. At the age of 8 years the patient underwent radionuclide dynamic cholescintigraphy, indicating poor accumulation of the radiotracer in the liver on one hand, and severe retention of the radiopharmaceutical in the blood pool (including the heart) on the other hand. Rotor syndrome was suspected and finally confirmed on molecular analysis. This case represents the first cholescintigraphy report in a pediatric patient with genetically proven Rotor syndrome.


Assuntos
Colecistografia/métodos , Vesícula Biliar/diagnóstico por imagem , Hiperbilirrubinemia Hereditária/diagnóstico , Icterícia/etiologia , Cintilografia/métodos , Criança , Diagnóstico Diferencial , Feminino , Humanos , Hiperbilirrubinemia Hereditária/complicações , Icterícia/diagnóstico
11.
J Hepatol ; 60(4): 773-81, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24361409

RESUMO

BACKGROUND & AIMS: Augmented susceptibility to infections increases mortality in patients with end-stage liver disease (ESLD). We sought to determine the contribution of selected genetic variants involved in inflammatory signalling downstream of the Toll-like receptor 4 (TLR4) to severe bacterial infections (SBIs) in patients with ESLD. METHODS: We retrospectively assessed incidence of SBIs in 336 adult ESLD patients enlisted for orthotopic liver transplantation (OLT) and genotyped them for TLR4 c.+1196C/T, CD14 c.-159C/T, TNFA c.-238G/A, TNFA c.-863C/A, IL1B c.-31C/T and IL1RN variable number of tandem repeats allelic variants. Principal findings were validated in an independent cohort of 332 ESLD patients. RESULTS: Thirty-four percent of patients from the identification cohort and 40% of patients from the validation cohort presented with SBI while enlisted for OLT. The presence of the variant allele TNFA c.-238A (rs361525) was associated with lower serum levels of TNF-α, and with significantly decreased risk of SBI in both cohorts. Multivariate analysis showed that the relative protection from SBI associated with this allele almost completely negated the increased susceptibility to SBI owed to advanced ESLD. Although not predictive of overall mortality, the presence of the TNFA c.-238A allele was associated with a complete prevention of SBI-related pre-transplant deaths. CONCLUSIONS: Our results suggest that genetic variability in inflammatory signalling is associated with the development of SBI in patients with ESLD. Specifically, we identified the importance of the TNFA c.-238A allele as a strong predictor of protection from SBI, and as a genetic marker associated with significantly improved pre-transplant survival in patients with SBI.


Assuntos
Infecções Bacterianas/genética , Infecções Bacterianas/prevenção & controle , Doença Hepática Terminal/complicações , Doença Hepática Terminal/genética , Transplante de Fígado , Fator de Necrose Tumoral alfa/genética , Adulto , Infecções Bacterianas/imunologia , Estudos de Coortes , Doença Hepática Terminal/imunologia , Feminino , Frequência do Gene , Estudos de Associação Genética , Marcadores Genéticos , Predisposição Genética para Doença , Variação Genética , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Estudos Retrospectivos , Receptor 4 Toll-Like/genética , Fator de Necrose Tumoral alfa/sangue
12.
Gastroenterology ; 144(2): 381-391, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23142137

RESUMO

BACKGROUND & AIMS: The Wnt signaling pathway is required for maintenance of the intestinal epithelia; blocking this pathway reduces the proliferative capacity of the intestinal stem cells. However, aberrant Wnt signaling leads to intestinal cancer. We investigated the roles of the Wnt pathway in homeostasis of the intestinal epithelium and during malignant transformation in human cells and mice. METHODS: We performed chromatin immunoprecipitation (ChIP) with DNA microarray analysis (ChIP-on-chip) to identify genes regulated by Wnt signaling in human colorectal cancer cells Colo320, DLD1, LS174T, and SW480. Formation of intestinal tumor was induced in C57BL/6J mice using azoxymethane and dextran sulfate. Intestinal tissues from these mice, as well as Apc(+/Min) and Apc(CKO/CKO)/Lgr5-EGFP-IRES-CreERT2 mice, were analyzed by immunohistochemistry and in situ hybridization. RESULTS: We identified promoter regions of 960 genes that interacted with the Wnt pathway nuclear effector T-cell factor 4 in 4 different human colorectal cancer-derived cell lines; 18 of these promoters were present in all chromatin precipitates. Wnt signaling up-regulated a member of the tumor necrosis factor receptor superfamily called TROY. Levels of TROY messenger RNA were increased in human cells with deficiencies in the adenomatous polyposis coli (APC) gene and in cells stimulated with the Wnt3a ligand. Expression of Troy was significantly up-regulated in neoplastic tissues from mice during intestinal tumorigenesis. Lineage tracing experiments revealed that Troy is produced specifically by fast-cycling intestinal stem cells. TROY associated with a unique marker of these cells, leucine-rich repeat-containing G-protein coupled receptor (LGR) 5. In organoids established from the intestinal crypts, Troy suppressed signaling mediated by R-spondin, a Wnt agonist. CONCLUSIONS: TROY is up-regulated in human colorectal cancer cell lines and in intestinal tumors in mice. It functions as a negative modulator of the Wnt pathway in LGR5-positive stem cells.


Assuntos
Transformação Celular Neoplásica/genética , Regulação Neoplásica da Expressão Gênica , Mucosa Intestinal/metabolismo , Células-Tronco Neoplásicas/metabolismo , Receptores Acoplados a Proteínas G/fisiologia , Receptores do Fator de Necrose Tumoral/fisiologia , Via de Sinalização Wnt/fisiologia , Animais , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/patologia , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Humanos , Imuno-Histoquímica , Hibridização In Situ , Mucosa Intestinal/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Neoplasias Experimentais , Células-Tronco Neoplásicas/patologia , Análise de Sequência com Séries de Oligonucleotídeos , RNA Neoplásico/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa
13.
Hepatol Res ; 44(10): E304-E308, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24164717

RESUMO

Benign recurrent intrahepatic cholestasis (BRIC) is an autosomal recessive liver disorder characterized by recurrent episodes of jaundice and itching. Episodes of cholestasis last variously from 1 week to several months, may start at any age and usually resolve spontaneously. No effective treatment has been found as yet. We report a case of genetically proven BRIC in a male patient who developed three episodes of pruritus and jaundice at the age of 14, 16 and 19 years. During the third episode, he did not respond to pharmacological medical therapy, and fractionated plasma separation and absorption (FPSA, Prometheus) was performed to manage intractable pruritus. The treatment immediately alleviated pruritus, lowered serum bilirubin concentration and induced sustained remission in the 5-year follow up. FPSA seems to be a safe and effective way of treatment for BRIC in patients with severe pruritus and prolonged jaundice.

14.
Discov Nano ; 19(1): 106, 2024 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-38907808

RESUMO

In recent years, it has been recognized that mechanical forces play an important regulative role in living organisms and possess a direct impact on crucial cell functions, ranging from cell growth to maintenance of tissue homeostasis. Advancements in mechanobiology have revealed the profound impact of mechanical signals on diverse cellular responses that are cell type specific. Notably, numerous studies have elucidated the pivotal role of different mechanical cues as regulatory factors influencing various cellular processes, including cell spreading, locomotion, differentiation, and proliferation. Given these insights, it is unsurprising that the responses of cells regulated by physical forces are intricately linked to the modulation of nanoparticle uptake kinetics and processing. This complex interplay underscores the significance of understanding the mechanical microenvironment in shaping cellular behaviors and, consequently, influencing how cells interact with and process nanoparticles. Nevertheless, our knowledge on how localized physical forces affect the internalization and processing of nanoparticles by cells remains rather limited. A significant gap exists in the literature concerning a systematic analysis of how mechanical cues might bias the interactions between nanoparticles and cells. Hence, our aim in this review is to provide a comprehensive and critical analysis of the existing knowledge regarding the influence of mechanical cues on the complicated dynamics of cell-nanoparticle interactions. By addressing this gap, we would like to contribute to a detailed understanding of the role that mechanical forces play in shaping the complex interplay between cells and nanoparticles.

15.
Biomater Biosyst ; 14: 100093, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38585282

RESUMO

Recently, it has been recognized that physical abnormalities (e.g. elevated solid stress, elevated interstitial fluid pressure, increased stiffness) are associated with tumor progression and development. Additionally, these mechanical forces originating from tumor cell environment through mechanotransduction pathways can affect metabolism. On the other hand, mitochondria are well-known as bioenergetic, biosynthetic, and signaling organelles crucial for sensing stress and facilitating cellular adaptation to the environment and physical stimuli. Disruptions in mitochondrial dynamics and function have been found to play a role in the initiation and advancement of cancer. Consequently, it is logical to hypothesize that mitochondria dynamics subjected to physical cues may play a pivotal role in mediating tumorigenesis. Recently mitochondrial biogenesis and turnover, fission and fusion dynamics was linked to mechanotransduction in cancer. However, how cancer cell mechanics and mitochondria functions are connected, still remain poorly understood. Here, we discuss recent studies that link mechanical stimuli exerted by the tumor cell environment and mitochondria dynamics and functions. This interplay between mechanics and mitochondria functions may shed light on how mitochondria regulate tumorigenesis.

16.
Nanoscale Adv ; 5(16): 4250-4268, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37560414

RESUMO

Iron oxide nanoparticles (IONPs) are being actively researched in various biomedical applications, particularly as magnetic resonance imaging (MRI) contrast agents for diagnosing various liver pathologies like nonalcoholic fatty liver diseases, nonalcoholic steatohepatitis, and cirrhosis. Emerging evidence suggests that IONPs may exacerbate hepatic steatosis and liver injury in susceptible livers such as those with nonalcoholic fatty liver disease. However, our understanding of how IONPs may affect steatotic cells at the sub-cellular level is still fragmented. Generally, there is a lack of studies identifying the molecular mechanisms of potential toxic and/or adverse effects of IONPs on "non-heathy" in vitro models. In this study, we demonstrate that IONPs, at a dose that does not cause general toxicity in hepatic cells (Alexander and HepG2), induce significant toxicity in steatotic cells (cells loaded with non-toxic doses of palmitic acid). Mechanistically, co-treatment with PA and IONPs resulted in endoplasmic reticulum (ER) stress, accompanied by the release of cathepsin B from lysosomes to the cytosol. The release of cathepsin B, along with ER stress, led to the activation of apoptotic cell death. Our results suggest that it is necessary to consider the interaction between IONPs and the liver, especially in susceptible livers. This study provides important basic knowledge for the future optimization of IONPs as MRI contrast agents for various biomedical applications.

17.
ACS Biomater Sci Eng ; 9(5): 2408-2425, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37001010

RESUMO

It has become evident that physical stimuli of the cellular microenvironment transmit mechanical cues regulating key cellular functions, such as proliferation, migration, and malignant transformation. Accumulating evidence suggests that tumor cells face variable mechanical stimuli that may induce metabolic rewiring of tumor cells. However, the knowledge of how tumor cells adapt metabolism to external mechanical cues is still limited. We therefore designed soft 3D collagen scaffolds mimicking a pathological mechanical environment to decipher how liver tumor cells would adapt their metabolic activity to physical stimuli of the cellular microenvironment. Here, we report that the soft 3D microenvironment upregulates the glycolysis of HepG2 and Alexander cells. Both cell lines adapt their mitochondrial activity and function under growth in the soft 3D microenvironment. Cells grown in the soft 3D microenvironment exhibit marked mitochondrial depolarization, downregulation of mitochondrially encoded cytochrome c oxidase I, and slow proliferation rate in comparison with stiff monolayer cultures. Our data reveal the coupling of liver tumor glycolysis to mechanical cues. It is proposed here that soft 3D collagen scaffolds can serve as a useful model for future studies of mechanically regulated cellular functions of various liver (potentially other tissues as well) tumor cells.


Assuntos
Neoplasias Hepáticas , Microambiente Tumoral , Humanos , Dinâmica Mitocondrial , Colágeno
18.
Adv Drug Deliv Rev ; 197: 114828, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37075952

RESUMO

Although several nanomedicines got clinical approval over the past two decades, the clinical translation rate is relatively small so far. There are many post-surveillance withdrawals of nanomedicines caused by various safety issues. For successful clinical advancement of nanotechnology, it is of unmet need to realize cellular and molecular foundation of nanotoxicity. Current data suggest that lysosomal dysfunction caused by nanoparticles is emerging as the most common intracellular trigger of nanotoxicity. This review analyzes prospect mechanisms of lysosomal dysfunction-mediated toxicity induced by nanoparticles. We summarized and critically assessed adverse drug reactions of current clinically approved nanomedicines. Importantly, we show that physicochemical properties have great impact on nanoparticles interaction with cells, excretion route and kinetics, and subsequently on toxicity. We analyzed literature on adverse reactions of current nanomedicines and hypothesized that adverse reactions might be linked with lysosomal dysfunction caused by nanomedicines. Finally, from our analysis it becomes clear that it is unjustifiable to generalize safety and toxicity of nanoparticles, since different particles possess distinct toxicological properties. We propose that the biological mechanism of the disease progression and treatment should be central in the optimization of nanoparticle design.


Assuntos
Nanomedicina , Nanopartículas , Humanos , Nanomedicina/métodos , Nanotecnologia/métodos , Nanopartículas/toxicidade , Nanopartículas/química , Lisossomos
19.
PLoS One ; 18(7): e0288907, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37471416

RESUMO

BACKGROUND AND AIM: Gene defects contribute to the aetiology of intrahepatic cholestasis. We aimed to explore the outcome of whole-exome sequencing (WES) in a cohort of 51 patients with this diagnosis. PATIENTS AND METHODS: Both paediatric (n = 33) and adult (n = 18) patients with cholestatic liver disease of unknown aetiology were eligible. WES was used for reassessment of 34 patients (23 children) without diagnostic genotypes in ABCB11, ATP8B1, ABCB4 or JAG1 demonstrable by previous Sanger sequencing, and for primary assessment of additional 17 patients (10 children). Nasopharyngeal swab mRNA was analysed to address variant pathogenicity in two families. RESULTS: WES revealed biallelic variation in 3 ciliopathy genes (PKHD1, TMEM67 and IFT172) in 4 clinically unrelated index subjects (3 children and 1 adult), heterozygosity for a known variant in PPOX in one adult index subject, and homozygosity for an unreported splice-site variation in F11R in one child. Whereas phenotypes of the index patients with mutated PKHD1, TMEM67, and PPOX corresponded with those elsewhere reported, how F11R variation underlies liver disease remains unclear. Two unrelated patients harboured different novel biallelic variants in IFT172, a gene implicated in short-rib thoracic dysplasia 10 and Bardet-Biedl syndrome 20. One patient, a homozygote for IFT172 rs780205001 c.167A>C p.(Lys56Thr) born to first cousins, had liver disease, interpreted on biopsy aged 4y as glycogen storage disease, followed by adult-onset nephronophthisis at 25y. The other, a compound heterozygote for novel frameshift variant IFT172 NM_015662.3 c.2070del p.(Met690Ilefs*11) and 2 syntenic missense variants IFT172 rs776310391 c.157T>A p.(Phe53Ile) and rs746462745 c.164C>G p.(Thr55Ser), had a severe 8mo cholestatic episode in early infancy, with persisting hyperbilirubinemia and fibrosis on imaging studies at 17y. No patient had skeletal malformations. CONCLUSION: Our findings suggest association of IFT172 variants with non-syndromic cholestatic liver disease.


Assuntos
Colestase Intra-Hepática , Colestase , Humanos , Mutação , Sequenciamento do Exoma , Colestase/genética , Genótipo , Colestase Intra-Hepática/genética , Colestase Intra-Hepática/diagnóstico , Flavoproteínas/genética , Proteínas Mitocondriais/genética , Protoporfirinogênio Oxidase/genética , Proteínas do Citoesqueleto/genética , Proteínas Adaptadoras de Transdução de Sinal/genética
20.
J Hepatol ; 67(2): 214-215, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28495428
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