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1.
Oncology ; 2023 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-37989120

RESUMO

INTRODUCTION: Hepatocellular carcinoma (HCC) carcinogenesis is not yet fully known. Insulin-like Growth Factor-1 Receptor (IGF-1R) can translocate to the nucleus and modulate cellular growth, possibly participating in HCC development and aggressiveness. This study aims to evaluate the immunoexpression of IGF-1R in HCC, the cellular compartment involved, and its association with clinicopathological parameters and clinical outcomes. METHODS: Liver specimens from 111 HCC patients who underwent liver transplantation or partial surgical resections at a Brazilian referral hospital center were studied. IGF-1R expression was determined by immunohistochemistry, clinical data were collected from medical records, and pathological parameters were obtained from path review. RESULTS: IGF-1R nuclear expression was higher in the tumor than in the adjacent cirrhosis (p < 0.001). The odds of IGF-1R expression in the nucleus compared to the membrane are lower in the cirrhosis condition than in the tumor, suggesting an increase in the prevalence of nucleus expression relative to the membrane from cirrhosis to tumor. There was an association between IGF-1R nuclear expression in HCC and the moderate/poor grade of histologic differentiation (p < 0.001). However, long-term clinical outcomes were not associated with IGF-1R nuclear expression. CONCLUSION: The data presented here suggest the role of IGF-1R in HCC progression and carcinogenesis as its expression increases in the nucleus relative to the membrane, from cirrhosis to tumor, and it was associated with a poorer differentiated tumor grade. Further research is awaited to fully understand the mechanisms underlying this association.

2.
J Hepatol ; 69(6): 1294-1307, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30171870

RESUMO

BACKGROUND & AIMS: The liver is the main hematopoietic site in embryos, becoming a crucial organ in both immunity and metabolism in adults. However, how the liver adapts both the immune system and enzymatic profile to challenges in the postnatal period remains elusive. We aimed to identify the mechanisms underlying this adaptation. METHODS: We analyzed liver samples from mice on day 0 after birth until adulthood. Human biopsies from newborns and adults were also examined. Liver immune cells were phenotyped using mass cytometry (CyTOF) and expression of several genes belonging to immune and metabolic pathways were measured. Mortality rate, bacteremia and hepatic bacterial retention after E. coli challenge were analyzed using intravital and in vitro approaches. In a set of experiments, mice were prematurely weaned and the impact on gene expression of metabolic pathways was evaluated. RESULTS: Human and mouse newborns have a sharply different hepatic cellular composition and arrangement compared to adults. We also found that myeloid cells and immature B cells primarily compose the neonatal hepatic immune system. Although neonatal mice were more susceptible to infections, a rapid evolution to an efficient immune response was observed. Concomitantly, newborns displayed a reduction of several macronutrient metabolic functions and the normal expression level of enzymes belonging to lipid and carbohydrate metabolism was reached around the weaning period. Interestingly, early weaning profoundly disturbed the expression of several hepatic metabolic pathways, providing novel insights into how dietary schemes affect the metabolic maturation of the liver. CONCLUSION: In newborns, the immune and metabolic profiles of the liver are dramatically different to those of the adult liver, which can be explained by the differences in the liver cell repertoire and phenotype. Also, dietary and antigen cues may be crucial to guide liver development during the postnatal phase. LAY SUMMARY: Newborns face major challenges in the extra-uterine life. In fact, organs need to modify their cellular composition and gene expression profile in order to adapt to changes in both microbiota and diet throughout life. The liver is interposed between the gastrointestinal system and the systemic circulation, being the destination of all macronutrients and microbial products from the gut. Therefore, it is expected that delicately balanced mechanisms govern the transformation of a neonatal liver to a key organ in adults.


Assuntos
Recém-Nascido , Fígado/imunologia , Fígado/metabolismo , Adulto , Animais , Animais Recém-Nascidos , Biópsia , Infecções por Escherichia coli/imunologia , Feminino , Hepatócitos , Humanos , Metabolismo dos Lipídeos , Fígado/citologia , Metaboloma , Camundongos , Camundongos Endogâmicos C57BL , Células Progenitoras Mieloides/imunologia , Células Progenitoras Mieloides/fisiologia , Valor Nutritivo/fisiologia , Fagócitos/imunologia , Células Precursoras de Linfócitos B/imunologia , Desmame
3.
J Clin Lab Anal ; 32(6): e22410, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29453831

RESUMO

BACKGROUND: The most of the hepatitis C-infected patients remain undiagnosed until they develop severe liver damage or submitted for serological screening. OBJECTIVE: To evaluate a recombinant multiepitope protein for detection of IgG anti-hepatitis C virus. METHOD: A synthetic gene was cloned, expressed in Escherichia coli, and the recombinant protein was purified. Human serum panel consisted of 88 positives (20 HCV genotyped) and 376 negatives for hepatitis C, 6 positives for human acquired immunodeficiency virus, 6 syphilis positives, 6 hepatitis B positives were tested by IgG antihepatitis C virus using the protein by enzyme-linked immunosorbent assay. In addition, 20 positive (all genotyped samples) and 20 negative samples were also tested by immunoblot and dot blot assays. RESULTS: Positive hepatitis C sera were strongly reactive against the protein by immunoblot assay. In the dot blot assay, positive sera were reactive until 1:1000 dilution and there were no false positive results in the hepatitis C negative sera. In the enzyme-linked immunosorbent assay, positive and negative sera had significant discrimination. No cross-reaction was observed in samples positive for syphilis; human acquired immunodeficiency virus and hepatitis B. All 20 genotyped samples were positive by the three methods. CONCLUSION: The multiepitope protein used here has a lower cost compared to production of each antigen separately and could be an alternative for the serological diagnosis of hepatitis C.

4.
Artigo em Inglês | MEDLINE | ID: mdl-39091648

RESUMO

Background: Liver transplantation (LT) is the best treatment for end-stage liver disease; however, biliary complications (BCs) still pose a significant challenge. Among the post-transplant BC, strictures and biliary fistulas are the most common. Biliary strictures are classified as anastomotic and non-anastomotic. Some previous studies suggest an association between post-transplant biliary strictures and cytomegalovirus (CMV) infection. In this study, we aimed to identify whether there is an association between CMV infection and biliary strictures in patients undergoing LT. Methods: A retrospective study of 175 patients aged ≥18 years undergoing LT at Felicio Rocho Hospital between 2011 and 2017 was conducted. All included patients received grafts perfused with Institut Georges Lopez-1 (IGL-1) solution from brain-dead donors, survived post-transplantation for more than 120 days, and had a minimum follow-up of 12 months after LT. The diagnosis of CMV was made by antigenemia and biliary strictures by magnetic resonance cholangiopancreatography (MRCP). Results: The average age of the recipients was 54 years. Postoperative BCs occurred in 12% of transplants. The most common BC was stricture (9.1%), with a predominance of anastomotic strictures (AS) over non-AS (NAS) (87.5% vs. 12.5%, respectively). CMV infection was confirmed in 22.9% of patients. In the univariate analysis, post-transplant CMV infection correlated with the development of BCs (P=0.01), as well as biliary strictures (P=0.008). In the multivariate analysis, however, only model for end-stage liver disease (MELD) >21 was a risk factor for the development of BCs in general (P=0.02) and biliary strictures (P=0.01). Conclusions: CMV infection was not an independent risk factor for the development of non-anastomotic post-transplant biliary strictures in this study.

5.
Oncol Lett ; 23(1): 32, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34966448

RESUMO

The expression of the inositol 1,4,5-trisphosphate receptor type 3 (ITRP3) in hepatocytes is a common event in the pathogenesis of hepatocellular carcinoma (HCC), regardless of the type of underlying liver disease. However, it is not known whether ITPR3 expression in hepatocytes is involved in tumor maintenance. The aim of the present study was to determine whether there is an association between ITPR3 expression and clinical and morphological parameters using HCC samples obtained from liver explants from patients (n=53) with different etiologies of underlying chronic liver disease (CLD). ITPR3 expression, mitosis and apoptosis were analyzed in human liver samples by immunohistochemistry. Clinical and event-free survival data were combined to assess the relationship between ITPR3 and liver cancer growth in patients. RNA sequencing analysis was performed to identify apoptotic genes altered by ITPR3 expression in a liver tumor cell line. ITPR3 was highly expressed in HCC tumor cells relative to adjacent CLD tissue and healthy livers. There was an inverse correlation between ITPR3 expression and mitotic and apoptotic indices in HCC, suggesting that ITPR3 contributed to the maintenance of HCC by promoting resistance to apoptosis. This was confirmed by the upregulation of CTSB, CHOP and GADD45, genes involved in the apoptotic pathway in HCC. The expression of ITPR3 in the liver may be a promising prognostic marker of HCC.

6.
Hepatol Commun ; 4(5): 657-669, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32363317

RESUMO

Yellow fever (YF) is a viral hemorrhagic fever that typically involves the liver. Brazil recently experienced its largest recorded YF outbreak, and the disease was fatal in more than a third of affected individuals, mostly because of acute liver failure. Affected individuals are generally treated only supportively, but during the recent Brazilian outbreak, selected patients were treated with liver transplant. We took advantage of this clinical experience to better characterize the clinical and pathological features of YF-induced liver failure and to examine the mechanism of hepatocellular injury in YF, to identify targets that would be amenable to therapeutic intervention in preventing progression to liver failure and death. Patients with YF liver failure rapidly developed massive transaminase elevations, with jaundice, coagulopathy, thrombocytopenia, and usually hepatic encephalopathy, along with pathological findings that included microvesicular steatosis and lytic necrosis. Hepatocytes began to express the type 3 isoform of the inositol trisphosphate receptor (ITPR3), an intracellular calcium (Ca2+) channel that is not normally expressed in hepatocytes. Experiments in an animal model, isolated hepatocytes, and liver-derived cell lines showed that this new expression of ITPR3 was associated with increased nuclear Ca2+ signaling and hepatocyte proliferation, and reduced steatosis and cell death induced by the YF virus. Conclusion: Yellow fever often induces liver failure characterized by massive hepatocellular damage plus steatosis. New expression of ITPR3 also occurs in YF-infected hepatocytes, which may represent an endogenous protective mechanism that could suggest approaches to treat affected individuals before they progress to liver failure, thereby decreasing the mortality of this disease in a way that does not rely on the costly and limited resource of liver transplantation.

7.
Cell Calcium ; 91: 102264, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32957029

RESUMO

Hepatic ischemia-reperfusion injury is seen in a variety of clinical conditions, including hepatic thrombosis, systemic hypotension, and liver transplantation. Calcium (Ca2+) signaling mediates several pathophysiological processes in the liver, but it is not known whether and how intracellular Ca2+ channels are involved in the hepatocellular events secondary to ischemia-reperfusion. Using an animal model of hepatic ischemia-reperfusion injury, we observed a progressive increase in expression of the type 3 isoform of the inositol trisphosphate receptor (ITPR3), an intracellular Ca2+ channel that is not normally expressed in healthy hepatocytes. ITPR3 expression was upregulated, at least in part, by a combination of demethylation of the ITPR3 promoter region and the increased transcriptional activity of the nuclear factor of activated T-cells (NFAT). Additionally, expression of pro-inflammatory interleukins and necrotic surface area were less pronounced in livers of control animals compared to liver-specific ITPR3 KO mice subjected to hepatic damage. Corroborating these findings, ITPR3 expression and activation of NFAT were observed in hepatocytes of liver biopsies from patients who underwent liver ischemia caused by thrombosis after organ transplant. Together, these results are consistent with the idea that ITPR3 expression in hepatocytes plays a protective role during hepatic injury induced by ischemia-reperfusion.


Assuntos
Hepatócitos/metabolismo , Receptores de Inositol 1,4,5-Trifosfato/metabolismo , Fígado/metabolismo , Fígado/patologia , Substâncias Protetoras/metabolismo , Traumatismo por Reperfusão/metabolismo , Animais , Sinalização do Cálcio , Desmetilação do DNA , Modelos Animais de Doenças , Humanos , Masculino , Camundongos Endogâmicos C57BL , Camundongos Knockout , Fatores de Transcrição NFATC/metabolismo , Regiões Promotoras Genéticas/genética
8.
JHEP Rep ; 2(4): 100117, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32695965

RESUMO

BACKGROUND & AIMS: The precise determination of non-alcoholic fatty liver disease (NAFLD) onset is challenging. Thus, the initial hepatic responses to fat accumulation, which may be fundamental to our understanding of NAFLD evolution and clinical outcomes, are largely unknown. Herein, we chronologically mapped the immunologic and metabolic changes in the liver during the early stages of fatty liver disease in mice and compared this with human NAFLD samples. METHODS: Liver biopsies from patients with NAFLD (NAFLD activity score [NAS] 2-3) were collected for gene expression profiling. Mice received a high-fat diet for short periods to mimic initial steatosis and the hepatic immune response was investigated using a combination of confocal intravital imaging, gene expression, cell isolation, flow cytometry and bone marrow transplantation assays. RESULTS: We observed major immunologic changes in patients with NAS 2-3 and in mice in the initial stages of NAFLD. In mice, these changes significantly increased mortality rates upon drug-induced liver injury, as well as predisposing mice to bacterial infections. Moreover, deletion of Toll-like receptor 4 in liver cells dampened tolerogenesis, particularly in Kupffer cells, in the initial stages of dietary insult. CONCLUSION: The hepatic immune system acts as a sentinel for early and minor changes in hepatic lipid content, mounting a biphasic response upon dietary insult. Priming of liver immune cells by gut-derived Toll-like receptor 4 ligands plays an important role in liver tolerance in initial phases, but continuous exposure to insults may lead to damage and reduced ability to control infections. LAY SUMMARY: Fatty liver is a very common form of hepatic disease, leading to millions of cases of cirrhosis every year. Patients are often asymptomatic until becoming very sick. Therefore, it is important that we expand our knowledge of the early stages of disease pathogenesis, to enable early diagnosis. Herein, we show that even in the early stages of fatty liver disease, there are significant alterations in genes involved in the inflammatory response, suggesting that the hepatic immune system is disturbed even following minor and undetectable changes in liver fat content. This could have implications for the diagnosis and clinical management of fatty liver disease.

9.
PLoS One ; 12(7): e0180841, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28700679

RESUMO

Immunosenescence is an age-related reduction of immune system activity that can be associated with frailty. This study aimed to compare cytomegalovirus (CMV) and Epstein-Barr virus (EBV) reactivations (based on viremias) between young and elderly women who had a chronic CMV and/or EBV infection (i.e., an IgG+ serostatus) without an acute infection (i.e., an IgM- serostatus), and among the elderly group categorized according to frailty status. DNA was extracted from plasma using standard protocols and serostatus was determined by enzyme-linked immunosorbent assay. Quantitative real-time polymerase chain reaction analyses for CMV and EBV were carried out and viral loads were determined. Among elderly women (n = 71), 59% were positive for CMV, in contrast to only 8% of young women (n = 73). Elderly women classified as frail, pre-frail, and non-frail presented 82%, 56%, and 48% positivity for CMV, respectively. Frequency and viral load were significantly higher in the elderly group vs. the young group (p < 0.0001 and p = 0.01, respectively) and in elderly with frailty vs. those without frailty (p = 0.007 and p = 0.03, respectively). The frequency of CMV reactivation presented odds ratios of 11.77 for aging and 6.13 for frailty, and relative risks of 5.39 for aging and 1.93 for frailty. EBV was detected in 30% of the elderly women and 15% of the young women (p = 0.04); however, the viral load did not significantly differ between the two age groups. The frequency of EBV reactivation presented odds ratios of 2.36 for aging and 2.90 for frailty, and relative risks of 1.96 for aging and 2.12 for frailty. However, no difference in EBV viral load among the frailty status subgroups was found. In conclusion, the frequency of CMV reactivation was associated with aging and ongoing frailty, whereas the frequency of EBV reactivation was associated only with aging.


Assuntos
Envelhecimento/fisiologia , Citomegalovirus/fisiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , Citomegalovirus/genética , Ensaio de Imunoadsorção Enzimática , Infecções por Vírus Epstein-Barr/virologia , Feminino , Idoso Fragilizado/estatística & dados numéricos , Humanos , Pessoa de Meia-Idade , Plasmídeos/genética , Reação em Cadeia da Polimerase em Tempo Real , Adulto Jovem
10.
PLoS One ; 10(7): e0132336, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26147469

RESUMO

INTRODUCTION: Toll-like receptors (TLRs) play an important role in the recognition of microbial products and in host defense against infection. However, the massive release of inflammatory mediators into the bloodstream following TLR activation following sepsis is thought to contribute to disease pathogenesis. METHODS: Here, we evaluated the effects of preventive or therapeutic administration of monoclonal antibodies (mAbs) targeting either TLR2 or TLR4 in a model of severe polymicrobial sepsis induced by cecal ligation and puncture in mice. RESULTS: Pre-treatment with anti-TLR2 or anti-TLR4 mAb alone showed significant protection from sepsis-associated death. Protective effects were observed even when the administration of either anti-TLR2 or anti-TLR4 alone was delayed (i.e., 3 h after sepsis induction). Delayed administration of either mAb in combination with antibiotics resulted in additive protection. CONCLUSION: Although attempts to translate preclinical findings to clinical sepsis have failed so far, our preclinical experiments strongly suggest that there is a sufficient therapeutic window within which patients with ongoing sepsis could benefit from combined antibiotic plus anti-TLR2 or anti-TLR4 mAb treatment.


Assuntos
Anticorpos Monoclonais/farmacologia , Sepse/prevenção & controle , Receptor 2 Toll-Like/imunologia , Receptor 4 Toll-Like/imunologia , Animais , Anticorpos Monoclonais/imunologia , Modelos Animais de Doenças , Camundongos , Sepse/imunologia , Sepse/microbiologia , Sepse/patologia
11.
Rev Col Bras Cir ; 40(2): 160-3, 2013.
Artigo em Português | MEDLINE | ID: mdl-23752645

RESUMO

Laparoscopic liver resections are gaining adherents among surgeons, as they show rapid recovery, shorter hospital stay and better cosmetic results. The use of a laparoscopic radiofrequency device was first carried out successfully in Brazil for resection of hepatocellular carcinoma of the segment VI in two cirrhotic patients. Although intraoperative bleeding remains a major challenge for the surgeon during laparoscopic liver resections, in both cases the hepatic vascular exclusion was expendable and there was no need for blood transfusion. Patients were discharged on the fourth postoperative day.


Assuntos
Ablação por Cateter/instrumentação , Ablação por Cateter/métodos , Hepatectomia/métodos , Laparoscopia/métodos , Idoso , Carcinoma Hepatocelular/cirurgia , Feminino , Humanos , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade
12.
PLoS One ; 8(6): e66082, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23762470

RESUMO

Angiotensin-(1-7) [Ang-(1-7)] is a biologically active heptapeptide that may counterbalance the physiological actions of angiotensin II (Ang II) within the renin-angiotensin system (RAS). Here, we evaluated whether activation of the Mas receptor with the oral agonist, AVE 0991, would have renoprotective effects in a model of adriamycin (ADR)-induced nephropathy. We also evaluated whether the Mas receptor contributed for the protective effects of treatment with AT1 receptor blockers. ADR (10 mg/kg) induced significant renal injury and dysfunction that was maximal at day 14 after injection. Treatment with the Mas receptor agonist AVE 0991 improved renal function parameters, reduced urinary protein loss and attenuated histological changes. Renoprotection was associated with reduction in urinary levels of TGF-ß. Similar renoprotection was observed after treatment with the AT1 receptor antagonist, Losartan. AT1 and Mas receptor mRNA levels dropped after ADR administration and treatment with losartan reestablished the expression of Mas receptor and increased the expression of ACE2. ADR-induced nephropathy was similar in wild type (Mas(+/+) ) and Mas knockout (Mas (-/-)) mice, suggesting there was no endogenous role for Mas receptor activation. However, treatment with Losartan was able to reduce renal injury only in Mas(+/+) , but not in Mas (-/-) mice. Therefore, these findings suggest that exogenous activation of the Mas receptor protects from ADR-induced nephropathy and contributes to the beneficial effects of AT1 receptor blockade. Medications which target specifically the ACE2/Ang-(1-7)/Mas axis may offer new therapeutic opportunities to treat human nephropathies.


Assuntos
Angiotensina I/metabolismo , Doxorrubicina/efeitos adversos , Nefropatias/induzido quimicamente , Nefropatias/metabolismo , Fragmentos de Peptídeos/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Bloqueadores do Receptor Tipo 1 de Angiotensina II/farmacologia , Animais , Modelos Animais de Doenças , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Imidazóis/administração & dosagem , Imidazóis/farmacologia , Nefropatias/patologia , Nefropatias/prevenção & controle , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/metabolismo , Glomérulos Renais/patologia , Túbulos Renais/efeitos dos fármacos , Túbulos Renais/metabolismo , Túbulos Renais/patologia , Losartan/administração & dosagem , Losartan/farmacologia , Camundongos , Peptidil Dipeptidase A/metabolismo , Proto-Oncogene Mas , Proteínas Proto-Oncogênicas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptor Tipo 1 de Angiotensina/genética , Receptor Tipo 1 de Angiotensina/metabolismo , Receptores Acoplados a Proteínas G/genética , Fatores de Tempo
13.
Arq Bras Cir Dig ; 26(1): 40-3, 2013.
Artigo em Inglês, Português | MEDLINE | ID: mdl-23702869

RESUMO

BACKGROUND: Postoperative liver failure consequent to insufficiency of remnant liver is a feared complication in patients who underwent extensive liver resections. To induce rapid and significant hepatic hypertrophy, associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) has been recently developed for patients which tumor is previously considered unresectable. AIM: To present the Brazilian experience with ALPPS approach. METHOD: Were analyzed 39 patients who underwent hepatic resection using ALPPS in nine hospitals. The procedure was performed in two steps. The first operation was portal vein ligation and in situ splitting. In the second operation the right hepatic artery, right bile duct and the right hepatic vein were isolated and ligated. The extended right lobe was removed. There were 22 male (56.4%) and 17 female (43.6%). At the time of the first operation, the median age was 57.3 years (range: 20-83 years). RESULTS: The most common indication was liver metastasis in 32 patients (82.0%), followed by cholangiocarcinoma in three (7.7%). Two patients died (5.2%) during this period and did not undergo the second operation. The mean interval between the first and the second operation was 14.1 days (range: 5-30 days). The volume of the left lateral segment of the liver increased 83% (range 47-211.9%). Significant morbidity after ALPPS was seen in 23 patients (59.0%). The mortality rate was 12.8% (five patients). CONCLUSION: The ALPPS approach can enable resection in patients with lesions previously considered unresectable. It induces rapid liver hypertrophy avoiding liver failure in most patients. However still has high morbidity and mortality.


Assuntos
Hepatectomia/métodos , Neoplasias Hepáticas/cirurgia , Veia Porta/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Brasil , Feminino , Humanos , Ligadura , Masculino , Pessoa de Meia-Idade , Adulto Jovem
14.
Int J Hypertens ; 2012: 808726, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22319645

RESUMO

Renal ischemia and reperfusion (I/R) is the major cause of acute kidney injury in hospitalized patients. Mechanisms underlying reperfusion-associated injury include recruitment and activation of leukocytes and release of inflammatory mediators. In this study, we investigated the renal effects of acute administration of AVE0991, an agonist of Mas, the angiotensin-(1-7) receptor, the angiotensin-(1-7) receptor, in a murine model of renal I/R. Male C57BL/6 wild-type or Mas(-/-) mice were subjected to 30 min of bilateral ischemia and 24 h of reperfusion. Administration of AVE0991 promoted renoprotective effects, as seen by improvement of function, decreased tissue injury, prevention of local and remote leucocyte infiltration, and release of the chemokine, CXCL1. I/R injury was similar in WT and Mas(-/-) mice, suggesting that endogenous activation of this receptor does not control renal damage under baseline conditions. In conclusion, pharmacological interventions using Mas receptor agonists may represent a therapeutic opportunity for the treatment of renal I/R injury.

15.
Arq Neuropsiquiatr ; 68(4): 597-602, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20730316

RESUMO

OBJECTIVE: Hepatic encephalopathy (HE) is a neuropsychiatric syndrome resulting from liver failure. In the present study, we aimed to standardize an animal model of HE induced by thioacetamide (TAA) in C57BL/6 mice evaluating behavioral symptoms in association with liver damage and alterations in neurotransmitter release. METHOD: HE was induced by an intraperitoneal single dose of TAA (200 mg/kg, 600 mg/kg or 1,200 mg/kg). Behavioral symptoms were evaluated using the SHIRPA battery. Liver damage was confirmed by histopathological analysis. The glutamate release was measured using fluorimetric assay. RESULTS: The neuropsychiatric state, motor behavior and reflex and sensory functions were significantly altered in the group receiving 600 mg/kg of TAA. Biochemical analysis revealed an increase in the glutamate release in the cerebral cortex of HE mice. CONCLUSION: HE induced by 600 mg/kg TAA injection in C57BL/6 mice seems to be a suitable model to investigate the pathogenesis and clinical disorders of HE.


Assuntos
Comportamento Animal/efeitos dos fármacos , Encefalopatia Hepática/induzido quimicamente , Falência Hepática Aguda/induzido quimicamente , Atividade Motora/efeitos dos fármacos , Tioacetamida/toxicidade , Animais , Modelos Animais de Doenças , Ácido Glutâmico/análise , Falência Hepática Aguda/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL
16.
Acta Cir Bras ; 23(4): 315-21, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18641800

RESUMO

PURPOSE: To evaluate the effects of hyperbaric oxygen (HO) therapy in the protection against liver ischemia/reperfusion injury. METHODS: Thirty-two male Wistar rats were divided into four groups of eight animals each: group A - laparotomy and liver manipulation, group B - liver ischemia and reperfusion, group C - HO pretreatment for 60 min followed by liver ischemia and reperfusion, and group D - pretreatment with ambient air at 2.5 absolute atmospheres for 60 min followed by liver ischemia and reperfusion. Plasma was assayed for aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH). Intra-arterial blood pressure was monitored continuously. Myeloperoxidase activity in the liver and lung was assessed 30 min after reperfusion. RESULTS: Plasma AST, ALT and LDH increased after reperfusion in all animals. Plasma ALT values and myeloperoxidase activity in the liver parenchyma were higher in HO-pretreated animals than in groups A, B and D. HO had a negative hemodynamic effect during liver reperfusion. CONCLUSION: Liver preconditioning with hyperbaric oxygen therapy aggravated liver ischemia/reperfusion injury in rats as demonstrated by plasma ALT and liver myeloperoxidase activity.


Assuntos
Alanina Transaminase/sangue , Oxigenoterapia Hiperbárica/efeitos adversos , Precondicionamento Isquêmico/efeitos adversos , Hepatopatias/etiologia , Fígado/irrigação sanguínea , Traumatismo por Reperfusão/etiologia , Animais , Aspartato Aminotransferases/sangue , Pressão Sanguínea/fisiologia , Determinação da Pressão Arterial , Modelos Animais de Doenças , L-Lactato Desidrogenase/sangue , Hepatopatias/prevenção & controle , Masculino , Estresse Oxidativo , Ratos , Ratos Wistar , Traumatismo por Reperfusão/prevenção & controle
17.
ABCD (São Paulo, Impr.) ; 26(1): 40-43, jan.-mar. 2013. tab
Artigo em Português | LILACS | ID: lil-674140

RESUMO

RACIONAL: Insuficiência hepática pós-operatória devido à remanescente hepático pequeno tem sido complicação temida em pacientes que são submetidos à ressecção hepática extensa. A ligadura da veia porta associada à bipartição do fígado para hepatectomia em dois estágios (ALPPS) foi desenvolvida recentemente com a finalidade de induzir rápida e significante regeneração do fígado para pacientes em que o tumor é previamente considerado irressecável. OBJETIVO: Apresentar a experiência brasileira com o ALPPS. MÉTODO: Foram analisados 39 pacientes submetidos ao procedimento ALPPS em nove hospitais. Ele foi realizado em duas etapas. A primeira operação consistiu em ligadura do ramo direito da veia porta e bipartição hepática. Na segunda, os ramos direito da artéria hepática, via biliar e veia hepática foram ligados e o lobo hepático direito estendido foi removido. Foram 22 pacientes do sexo masculino (56,4%) e 17 do feminino (43,6%). A média de idade foi 57,3 anos (variando de 20 a 83 anos). RESULTADOS: A indicação mais comum foi metástase hepática em 32 pacientes (82,0%), seguida por colangiocarcinoma em três pacientes (7,7%). Dois morreram neste intervalo e não foram submetidos à segunda operação. O intervalo médio da primeira para a segunda operação foi de 14,1 dias (variando de 5-30 dias). O volume do segmento lateral esquerdo apresentou aumento de 83% (variando de 47-211,9%). Morbidade significante foi observada em 23 pacientes (59,0%). A mortalidade foi de 12,8% (cinco pacientes). CONCLUSÃO: O procedimento ALPPS permite ressecção hepática em pacientes com lesões consideradas previamente irressecáveis por induzir rápida hipertrofia do fígado evitando a insuficiência hepática na maioria dos pacientes. Porém ainda apresenta elevada morbidade e mortalidade.


BACKGROUND: Postoperative liver failure consequent to insufficiency of remnant liver is a feared complication in patients who underwent extensive liver resections. To induce rapid and significant hepatic hypertrophy, associating liver partition and portal vein ligation for staged hepatectomy (ALPPS) has been recently developed for patients which tumor is previously considered unresectable. AIM: To present the Brazilian experience with ALPPS approach. METHOD: Were analyzed 39 patients who underwent hepatic resection using ALPPS in nine hospitals. The procedure was performed in two steps. The first operation was portal vein ligation and in situ splitting. In the second operation the right hepatic artery, right bile duct and the right hepatic vein were isolated and ligated. The extended right lobe was removed. There were 22 male (56.4%) and 17 female (43.6%). At the time of the first operation, the median age was 57.3 years (range: 20-83 years). RESULTS: The most common indication was liver metastasis in 32 patients (82.0%), followed by cholangiocarcinoma in three (7.7%). Two patients died (5.2%) during this period and did not undergo the second operation. The mean interval between the first and the second operation was 14.1 days (range: 5-30 days). The volume of the left lateral segment of the liver increased 83% (range 47-211.9%). Significant morbidity after ALPPS was seen in 23 patients (59.0%). The mortality rate was 12.8% (five patients). CONCLUSION: The ALPPS approach can enable resection in patients with lesions previously considered unresectable. It induces rapid liver hypertrophy avoiding liver failure in most patients. However still has high morbidity and mortality.


Assuntos
Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem , Hepatectomia/métodos , Neoplasias Hepáticas/cirurgia , Veia Porta/cirurgia , Brasil , Ligadura
20.
Arq. neuropsiquiatr ; 68(4): 597-602, Aug. 2010. graf, ilus
Artigo em Inglês | LILACS | ID: lil-555241

RESUMO

OBJECTIVE: Hepatic encephalopathy (HE) is a neuropsychiatric syndrome resulting from liver failure. In the present study, we aimed to standardize an animal model of HE induced by thioacetamide (TAA) in C57BL/6 mice evaluating behavioral symptoms in association with liver damage and alterations in neurotransmitter release. METHOD: HE was induced by an intraperitoneal single dose of TAA (200 mg/kg, 600 mg/kg or 1,200 mg/kg). Behavioral symptoms were evaluated using the SHIRPA battery. Liver damage was confirmed by histopathological analysis. The glutamate release was measured using fluorimetric assay. RESULTS: The neuropsychiatric state, motor behavior and reflex and sensory functions were significantly altered in the group receiving 600 mg/kg of TAA. Biochemical analysis revealed an increase in the glutamate release in the cerebral cortex of HE mice. CONCLUSION: HE induced by 600mg/kg TAA injection in C57BL/6 mice seems to be a suitable model to investigate the pathogenesis and clinical disorders of HE.


OBJETIVO: A encefalopatia hepática (EH) é uma síndrome neuropsiquiátrica resultante da falência hepática. O objetivo do presente estudo foi estabelecer um modelo de EH induzida por tioacetamida (TAA) em camundongos C57BL/6 avaliando transtornos comportamentais, falência hepática e alterações na liberação de neurotransmissores. MÉTODO: A EH foi induzida por meio de uma única dose intraperitoneal de TAA (200 mg/kg, 600 mg/kg, 1.200 mg/kg). As alterações comportamentais foram avaliadas utilizando a bateria SHIRPA. A falência hepática foi confirmada através de análises histopatológicas e a liberação de glutamato medida, por ensaio fluorimétrico. RESULTADOS: Foram encontradas alterações significativas no estado neuropsiquiátrico, comportamento motor e função reflexa e sensorial no grupo que recebeu 600 mg/kg de TAA. Análises bioquímicas revelaram aumento na liberação de glutamato no córtex cerebral dos camundongos com EH. CONCLUSÃO: A EH induzida por 600 mg/kg de TAA em camundongos C57BL/6 parece ser um modelo apropriado para a investigação da patogênese e dos transtornos clínicos da EH.


Assuntos
Animais , Masculino , Camundongos , Comportamento Animal/efeitos dos fármacos , Encefalopatia Hepática/induzido quimicamente , Falência Hepática Aguda/induzido quimicamente , Atividade Motora/efeitos dos fármacos , Tioacetamida/toxicidade , Modelos Animais de Doenças , Ácido Glutâmico/análise , Falência Hepática Aguda/metabolismo
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