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1.
Immunopharmacol Immunotoxicol ; 40(4): 353-357, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30111221

RESUMO

AIM: DNA vaccines have emerged as a promising strategy for cancer immunotherapy; however, their immunogenicity is weak. Fms-like tyrosine kinase 3-ligand (Flt3L) has been exploited for its ability to increase the proliferation of dendritic cells (DCs). The aim of the present study was to investigate whether co-administration of an adjuvant plasmid expressing mouse Flt3L and a DNA vaccine of the Mucin 1 (MUC1) antigen enhances immune responses. METHODS: The recombinant plasmids pVAX1-MUC1 and pVAX1-Flt3L were constructed and injected into mice intramuscularly (i.m.), followed by electroporation. The humoral and cellular immune responses after immunization were examined by enzyme linked immunosorbent assay (ELISA) and enzyme-linked immunospot assay (ELISPOT), respectively. To evaluate the anti-tumor efficacy of the plasmids, a mouse model of MUC1-expressing tumors was established. RESULTS: The results showed that co-administration of an adjuvant plasmid and a DNA vaccine stimulated the production of higher titers of specific antibodies and a T cell response and suppressed the growth of subcutaneous tumors expressing MUC1. Collectively, our results indicate that a plasmid expressing murine Flt3L could stimulate stronger immune responses. CONCLUSION: These observations emphasize the potential of Flt3L as an adjuvant for colon cancer DNA vaccines.


Assuntos
Adjuvantes Imunológicos/farmacologia , Vacinas Anticâncer/farmacologia , Neoplasias do Colo/imunologia , Proteínas de Membrana , Mucina-1 , Neoplasias Experimentais/imunologia , Plasmídeos/farmacologia , Vacinas de DNA/farmacologia , Adjuvantes Imunológicos/genética , Animais , Vacinas Anticâncer/genética , Vacinas Anticâncer/imunologia , Neoplasias do Colo/genética , Neoplasias do Colo/patologia , Neoplasias do Colo/terapia , Feminino , Proteínas de Membrana/genética , Proteínas de Membrana/imunologia , Camundongos , Mucina-1/genética , Mucina-1/imunologia , Neoplasias Experimentais/genética , Neoplasias Experimentais/patologia , Neoplasias Experimentais/terapia , Plasmídeos/genética , Plasmídeos/imunologia , Vacinas de DNA/genética , Vacinas de DNA/imunologia
2.
Can J Gastroenterol Hepatol ; 2018: 2784537, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30065915

RESUMO

Cirrhosis is the common end stage of a number of chronic liver conditions and a significant cause of morbidity and mortality. With the growing epidemic of obesity and metabolic syndrome, nonalcoholic fatty liver disease (NAFLD) has become the most common cause of chronic liver disease worldwide and will become one of the leading causes of cirrhosis. Increased awareness and understanding of NAFLD cirrhosis are essential. To date, there has been no published systematic review on NAFLD cirrhosis. Thus, this article reviews recent studies on the epidemiology, risk factors, clinical presentation, diagnosis, management, and prognosis of NAFLD cirrhosis.


Assuntos
Carcinoma Hepatocelular/prevenção & controle , Cirrose Hepática/diagnóstico , Cirrose Hepática/epidemiologia , Neoplasias Hepáticas/prevenção & controle , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Vigilância da População , Carcinoma Hepatocelular/diagnóstico , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/prevenção & controle , Varizes Esofágicas e Gástricas/diagnóstico , Varizes Esofágicas e Gástricas/prevenção & controle , Humanos , Cirrose Hepática/complicações , Cirrose Hepática/terapia , Neoplasias Hepáticas/diagnóstico , Transplante de Fígado , Hepatopatia Gordurosa não Alcoólica/complicações , Prevalência , Prognóstico , Fatores de Risco
3.
Eur Arch Otorhinolaryngol ; 275(8): 2013-2019, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29948263

RESUMO

PURPOSE: The objective of this study is to analyze the relationship between chronic rhino-sinusitis (CRS) and systemic symptoms in patients with IgG4-related disease (IgG4-RD). PATIENTS AND METHODS: The patients with IgG4-RD, confirmed by restrict association with clinical and histopathological manifestations between March 2013 and July 2016, were enrolled and followed-up for 1 year at the Tongren Hospital, Capital Medical University. The patients were divided into two groups: the case group included IgG4-RD patients with CRS confirmed by clinical and imaging, while the control group included IgG4-RD patients without CRS confirmed by clinical and imaging. Age, gender, clinical manifestations, the percentage of eosinophils in peripheral blood, sedimentation (ESR), C-reaction protein, serum IgE and IgG4 levels, histopathology, and treatment drugs at the baseline and 1 year of follow-up were compared between the two groups. RESULTS: A total of 46 cases met the diagnostic criteria for IgG4-RD. A total of 30 patients (65.2%) had IgG4-RD complicated with CRS, and were aged 49.7 ± 13.4 years, with male:female ratio = 2:1. The disease duration in the case group was longer than that in the control group (3.0 versus 0.8, p = 0.009). The ratio of ocular involvement was higher (86.7 versus 60%, p < 0.001), and allergic manifestations including drug allergy, asthma, and allergic skin were more common (56.5 versus 20%, p = 0.004), with a higher percentage of eosinophils in peripheral blood (8.5 versus 3.3%, p = 0.018) and more sensitive to glucocorticoids (6.0 versus 3.5, p = 0.004) than those in the control group. CONCLUSIONS: CRS in patients with IgG4-RD was closely associated with IgG4-related ocular lesions, which was more prone to allergic manifestations accompanied by raised percentage of eosinophils in peripheral blood. The treatment of patients with IgG4-RD complicated with CRS was more effective than those with IgG4-RD without CRS.


Assuntos
Imunoglobulina G/sangue , Rinite/epidemiologia , Sinusite/epidemiologia , Asma/epidemiologia , Estudos de Casos e Controles , China/epidemiologia , Doença Crônica , Dermatite/epidemiologia , Hipersensibilidade a Drogas/epidemiologia , Eosinófilos/metabolismo , Oftalmopatias/epidemiologia , Feminino , Seguimentos , Glucocorticoides/uso terapêutico , Humanos , Masculino , Pessoa de Meia-Idade
4.
World J Gastroenterol ; 22(8): 2483-93, 2016 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-26937136

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is the most common form of chronic liver disease and its incidence is increasing worldwide. However, the underlying mechanisms leading to the development of NAFLD are still not fully understood. Glycosyltransferases (GTs) are a diverse class of enzymes involved in catalyzing the transfer of one or multiple sugar residues to a wide range of acceptor molecules. GTs mediate a wide range of functions from structure and storage to signaling, and play a key role in many fundamental biological processes. Therefore, it is anticipated that GTs have a role in the pathogenesis of NAFLD. In this article, we present an overview of the basic information on NAFLD, particularly GTs and glycosylation modification of certain molecules and their association with NAFLD pathogenesis. In addition, the effects and mechanisms of some GTs in the development of NAFLD are summarized.


Assuntos
Tecido Adiposo/enzimologia , Glicosiltransferases/metabolismo , Fígado/enzimologia , Hepatopatia Gordurosa não Alcoólica/enzimologia , Tecido Adiposo/patologia , Animais , Glicosilação , Humanos , Fígado/patologia , Hepatopatia Gordurosa não Alcoólica/patologia , Processamento de Proteína Pós-Traducional , Transdução de Sinais
5.
Int J Mol Sci ; 14(11): 21435-46, 2013 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-24173238

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is characterized by triglyceride (TG) accumulation in hepatocytes. Very low density lipoprotein (VLDL) is a major secretory product of the liver that transports endogenously synthesized TG. Disrupted VLDL secretion may contribute to the accumulation of TG in hepatocytes. ApoB100 (apolipoprotein B100) is a glycoprotein and an essential protein component of VLDL. Its glycosylation may affect VLDL assembly and secretion. However, which glycosyltransferase catalyzes apoB100 glycosylation is unknown. In this study, we cloned the GLT8D2 (glycosyltransferase 8 domain containing 2) gene from HepG2 cells and generated a series of plasmids for in vitro studies of its molecular functions. We discovered that GLT8D2 was localized in the ER, interacted with apoB100, and positively regulated the levels of apoB100 protein in HepG2 cells. Based on these results, we propose that GLT8D2 is a glycosyltransferase of apoB100 that regulates apoB100 levels in hepatocytes.


Assuntos
Apolipoproteína B-100/biossíntese , Fígado Gorduroso/genética , Glicosiltransferases/genética , Hepatócitos/enzimologia , Clonagem Molecular , Fígado Gorduroso/enzimologia , Fígado Gorduroso/patologia , Regulação Enzimológica da Expressão Gênica , Glicosiltransferases/metabolismo , Células Hep G2 , Hepatócitos/patologia , Humanos , Lipoproteínas VLDL/metabolismo , Hepatopatia Gordurosa não Alcoólica , Triglicerídeos/metabolismo
6.
Int J Mol Sci ; 13(11): 14698-706, 2012 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-23203089

RESUMO

To analyze the association between non-alcoholic fatty liver disease (NAFLD) and the incidence of diabetic nephropathy in patients with type 2 diabetes, the incidence of diabetic nephropathy was assessed in 413 type 2 diabetic patients, by testing the 24 h urinary albumin excretion rate (UAER). The NAFLD was diagnosed based on patient's medical history and liver ultrasound. The difference in diabetic nephropathy incidence between patients with and without NAFLD was tested by X². Multivariate logistic regression analysis was used to assess the factors associated with diabetic nephropathy among type 2 diabetic patients. Total 363 out of 413 type 2 diabetic patients were enrolled in this study. The incidences of NAFLD and diabetic nephropathy in participants were approximately 56% (202/363) and 38% (137/363) respectively, and there was no significant difference in the prevalence of diabetic nephropathy between patients with and without NAFLD (37.1% vs. 38.5%, p = 0.787). The duration of diabetes (odds ratio [OR] 1.065, 95% confidence interval [CI] 1.014--1.120, p = 0.012), waist circumference (OR 1.077, 95% CI 1.040--1.116, p = 0.000), and fasting blood glucose (FBG; OR 1.136, 95% CI 1.023--1.1262, p = 0.017) were significantly associated with diabetic nephropathy, whereas sex, high blood pressure, total cholesterol (TC), triglyceride (TG), and ankle brachial pressure index (ABI) were not significantly associated with the disorder. The present results suggest that NAFLD is not related to the incidence of diabetic nephropathy in type 2 diabetes, but the duration of diabetes, waist circumference, and FBG are important factors for diabetic nephropathy in type 2 diabetes.


Assuntos
Nefropatias Diabéticas/complicações , Nefropatias Diabéticas/epidemiologia , Hepatopatia Gordurosa não Alcoólica/complicações , Idoso , Diabetes Mellitus Tipo 2/complicações , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Estudos Retrospectivos , Fatores de Risco
7.
Int J Mol Sci ; 13(9): 12130-12139, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23109905

RESUMO

Fluctuations in serum autofluorescence (AF) intensity have recently been widely used as markers of certain diseases such as cancer. To determine the diagnostic value of serum AF intensity for liver fibrosis in rats, we induced liver fibrosis by subcutaneous injection of carbon tetrachloride into rats. The rat serum AF intensities were detected at the excitation wavelength of 337 nm and the emission wavelength of 512 nm. The degree of liver fibrosis was evaluated by Van Gieson's staining. The relationship between serum AF intensity and the degree of liver fibrosis was analyzed by Spearman and Pearson Correlation. The diagnostic sensitivity and specificity of the serum AF was determined by analyzing the receiver operating characteristic (ROC) curves. Our results show that the serum AF intensity in the rat liver fibrosis model increased when compared with control rats eight weeks and twelve weeks post induction of liver fibrosis. However, there was no significant difference in serum AF intensity between fibrotic and control rats at four week post induction. Furthermore, serum AF intensity correlated positively with the severity of the degree of hepatic fibrosis. ROC analysis further suggested that serum AF intensity is a valid marker for staging fibrosis. Therefore, it may potentially be developed as a novel diagnostic tool for hepatic fibrosis.


Assuntos
Fluorescência , Cirrose Hepática/sangue , Cirrose Hepática/diagnóstico , Animais , Biomarcadores/sangue , Masculino , Ratos , Ratos Sprague-Dawley
8.
Hepatol Int ; 5(4): 899-905, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21484128

RESUMO

AIM: To explore protective effect of probucol on liver injury induced by carbon tetrachloride (CCl4) in rats. METHODS: We used CCl4 to induce a rat model of liver injury. Some of those rats were treated with an oral administration of probucol. Liver function, blood lipid, liver tissue malondialdehyde (MDA), superoxide dismutase (SOD), and degree of liver fibrosis were analyzed. RESULTS: Probucol significantly decreased the elevation of serum aspartate transaminase, total bile acid, alkaline phosphatase and cholesterol, and improved liver histopathological changes (including fatty infiltration, inflammation cell infiltration, and fibrosis), decreased liver tissue MDA level, and increased liver tissue SOD level in liver injury rats. CONCLUSIONS: For the first time, we demonstrated that probucol has protective effect against liver injury in animal experiment. The antioxidant action of probucol may play an important role in its hepatoprotective mechanism. Probucol also can reduce serum cholesterol. Thus, probucol may have the potential use in clinical liver diseases in which oxidative stress may be present, especially for the patients with hypercholesterolemia.

9.
World J Gastroenterol ; 16(37): 4652-60, 2010 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-20872965

RESUMO

Nonalcoholic fatty liver disease (NAFLD) has become the most common liver disease in the United States and other developed countries and is expected to increase in the next few years. Emerging data suggest that some patients with NAFLD may progress to nonalcoholic steatohepatitis (NASH), cirrhosis and even hepatocellular carcinoma. NAFLD can also promote the development and progression of disease in other organ systems, such as the cardiovascular and endocrine (i.e. diabetes) systems. Thus, understanding the pathogenesis of NAFLD is of great clinical importance and is critical for the prevention and treatment of the disease. Although the "two-hit hypothesis" is generally accepted, the exact pathogenesis of NAFLD has not been clearly established. The liver is an important innate immune organ with large numbers of innate immune cells, including Kupffer cells (KCs), natural killer T (NKT) cells and natural killer (NK) cells. Recent data show that an imbalance in liver cytokines may be implicated in the development of fatty liver disease. For example, Th1 cytokine excess may be a common pathogenic mechanism for hepatic insulin resistance and NASH. Innate immune cells in the liver play important roles in the excessive production of hepatic Th1 cytokines in NAFLD. In addition, liver innate immune cells participate in the pathogenesis of NAFLD in other ways. For example, activated KCs can generate reactive oxygen species, which induce liver injury. This review will focus primarily on the possible effect and mechanism of KCs, NKT cells and NK cells in the development of NAFLD.


Assuntos
Fígado Gorduroso , Imunidade Inata , Fígado , Células T Matadoras Naturais/imunologia , Animais , Citocinas/imunologia , Dislipidemias/imunologia , Fígado Gorduroso/imunologia , Fígado Gorduroso/patologia , Humanos , Resistência à Insulina , Fígado/citologia , Fígado/imunologia , Fígado/patologia
12.
World J Gastroenterol ; 12(31): 5051-4, 2006 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-16937505

RESUMO

AIM: To investigate the differentiation of rat bone marrow stem cells in liver after partial hepatectomy. METHODS: Bone marrow cells were collected from the tibia of rat with partial hepatectomy, the medial and left hepatic lobes were excised. The bone marrow stem cells (Thy(+)CD3(-)CD45RA(-) cells) were enriched from the bone marrow cells by depleting red cells and fluorescence-activated cell sorting. The sorted bone marrow stem cells were labeled by PKH26-GL in vitro and autotransplanted by portal vein injection. After 2 wk, the transplanted bone marrow stem cells in liver were examined by the immunohistochemistry of albumin (hepatocyte-specific marker). RESULTS: The bone marrow stem cells (Thy(+)CD3(-)CD45RA(-) cells) accounted for 2.8% of bone marrow cells without red cells. The labeling rate of 10 microM PKH26-GL on sorted bone marrow stem cells was about 95%. There were sporadic PKH26-GL-labeled cells among hepatocytes in liver tissue section, and some of the cells expressed albumin. CONCLUSION: Rat bone marrow stem cells can differentiate into hepatocytes in regenerative environment and may participate in liver regeneration after partial hepatectomy.


Assuntos
Células da Medula Óssea/citologia , Células-Tronco Hematopoéticas/citologia , Hepatectomia/métodos , Fígado/patologia , Animais , Células da Medula Óssea/metabolismo , Diferenciação Celular , Células-Tronco Hematopoéticas/metabolismo , Hepatócitos/metabolismo , Fígado/metabolismo , Regeneração Hepática , Masculino , Ratos , Ratos Sprague-Dawley
13.
Zhonghua Gan Zang Bing Za Zhi ; 14(3): 178-82, 2006 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-16556410

RESUMO

OBJECTIVE: To study the changes of advanced glycation end products (AGEs) in different phases of a rat liver fibrosis model induced by CCl4, and the interventional effect of aminoguanidin (AG). METHODS: Fifty-four SD rats were divided into three groups: a control group, a CCl4 model group and an intervention group. Their blood serum AGEs and hyaluronic acid (HA) and AGEs in their liver homogenates were measured. These measurements were correlatively assessed to the degrees of liver fibrosis at different phases of the rat model before and after the intervention with aminoguanidin. RESULTS: The content of AGEs in their blood sera and liver homogenates, and the level of blood serum HA, and the score of liver fibrosis degree at week 12 in our rat liver fibrosis mode groups were significantly higher than those in the control group (P < 0.01). In the intervention group with aminoguanidin, these figures were lower than those in the liver fibrosis model group (P < 0.05). The content of AGEs in their blood sera and liver homogenates had a linear correlation with the level of HA in their blood sera. CONCLUSION: The contents of AGEs in their blood sera and liver homogenates were increased in the late phase of our rat liver fibrosis model. To some extent, the level of AGEs may reflect the fibrosis degree of the rat livers. Aminoguanidin has an interventional effect in our CCl4 induced rat liver fibrosis model.


Assuntos
Produtos Finais de Glicação Avançada/metabolismo , Guanidinas/uso terapêutico , Cirrose Hepática Experimental/tratamento farmacológico , Cirrose Hepática Experimental/metabolismo , Fígado/metabolismo , Animais , Tetracloreto de Carbono , Intoxicação por Tetracloreto de Carbono , Fígado/patologia , Cirrose Hepática Experimental/induzido quimicamente , Masculino , Ratos , Ratos Sprague-Dawley
15.
World J Gastroenterol ; 10(19): 2818-22, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15334677

RESUMO

AIM: To investigate the different effects of mesenchymal stem cells (MSCs) and hematopoietic stem cells (HSCs) on hepatic differentiation. METHODS: MSCs from rat bone marrow were isolated and cultured by standard methods. HSCs from rat bone marrow were isolated and purified by magnetic activated cell sorting. Both cell subsets were induced. Morphology, RT-PCR and immunocytochemistry were used to identify the hepatic differentiation grade. RESULTS: MSCs exhibited round in shape after differentiation, instead of fibroblast-like morphology before differentiation. Albumin mRNA and protein were expressed positively in MSCs, without detection of alpha-fetoprotein (AFP). HSCs were polygonal in shape after differentiation. The expression of albumin signal decreased and AFP signal increased. The expression of CK18 was continuous in MSCs and HSCs both before and after induction. CONCLUSION: Both MSCs and HSCs have hepatic differentiation capabilities. However, their capabilities are not the same. MSCs can differentiate into mature hepatocyte-like cells, never expressing early hepatic specific genes, while Thy-1.1(+) cells are inclined to differentiate into hepatic stem cell-like cells, with an increasing AFP expression and a decreasing albumin signal. CK18 mRNA is positive in Thy-1.1(+) cells and MSCs, negative in Thy-1.1(-) cells. It seems that CK18 has some relationship with Thy-1.1 antigen, and CK18 may be a predictive marker of hepatic differentiation capability.


Assuntos
Diferenciação Celular/fisiologia , Células-Tronco Hematopoéticas/citologia , Mesoderma/citologia , Células-Tronco/citologia , Animais , Sequência de Bases , Biomarcadores/análise , Células da Medula Óssea/citologia , Primers do DNA , Citometria de Fluxo , Separação Imunomagnética , Masculino , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase Via Transcriptase Reversa , alfa-Fetoproteínas/análise
17.
Zhonghua Gan Zang Bing Za Zhi ; 11(11): 673-5, 2003 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-14636444

RESUMO

OBJECTIVE: To observe the differentiation of bone marrow stem cells in rat hepatic fibrogenesis environment into hepatocytes. METHODS: Rat hepatic fibrosis was induced by subcutaneous injection of CCl4. Bone marrow stem cells with Thy positive, CD3 and CD45RA negative were enriched from the bone marrow by fluorescence-activated cell sorting. The bone marrow stem cells were labeled with PKH26-GL, and then autotransplanted. After six weeks, albumin, ck8 and a-smooth muscle actin expression were determined by immunocytochemistry. RESULTS: The PKH26-GL labeled cells expressed albumin and ck8, but did not express a-smooth muscle actin in hepatic fibrogenesis environment. CONCLUSION: Bone marrow stem cells in hepatic fibrogenesis environment can differentiate into hepatocytes, but can't differentiate into myofibroblasts


Assuntos
Células da Medula Óssea/patologia , Diferenciação Celular/fisiologia , Células-Tronco Hematopoéticas/patologia , Hepatócitos/patologia , Cirrose Hepática/patologia , Animais , Meio Ambiente , Masculino , Ratos , Ratos Sprague-Dawley
18.
World J Gastroenterol ; 6(4): 540-545, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11819643

RESUMO

AIM:To investigate effect of losartan, an AT1 receptor antagonist, on hepatic fibrosis induced by CCl(4); and to determine whether or not AT1 receptors are expressed on hepatic stellate cells. METHODS AND RESULTS:Fifty male Sprague-Dawley rats, weighing (180 plus minus20)g, were randomized into five groups (control group, model group, and three losartan treated groups), in which all rats were given the subcutaneous injection of 40% CCl(4)(every 3 days for 6 weeks) except for rats of control group. Rats of losartan-treated groups were treated with losartan (20 mg/kg, 10 mg/kg, 5 mg/kg, daily gavage). After 6 weeks liver tissue and serum samples of all rats were examined. Serum hyaluronic acid (HA), procollagen type III (PC III) were detected by radioimmunoassays. van Giesion collagen staining was used to evaluate the extracellular matrix of rats with liver fibrosis. The expression of AT1 receptors, transforming growth factor-beta (TGF-beta), and alpha-smooth muscle actinalpha-SMA) in liver tissue were determined by immunohistochemical techniques. Compared with model group, serum ALT and AST of losartan-treated groups were significantly reduced (italic>t = 4.20,P < 0.01 and italic>t = 4.57,P < 0.01). Serum HA and PC III also had significant differences (italic>t = 3.53,P<0.01 and t=2.20, P<0.05). The degree of fibrosis was improved by losartan and correlated with the expressions of AT1 receptors, TGF-beta, and alpha-SMA in liver tissue.CONCLUSION:AT1 receptor antagonist, losartan, could limit the progression of the hepatic fibrosis induced by CCl(4). The mechanism may be related to the decrease in the expression of AT1 receptors and TGF-beta, ameliorating the injury of hepatocytes; activation of local renin-angiotensin system might relate to hepatic fibrosis; and during progression of fibrosis, activated hepatic stellate cells might express AT1 receptors.

19.
World J Gastroenterol ; 6(6): 824-828, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11819703

RESUMO

AIM:To assess the effect of ACE inhibitor and Ang II type 1 (AT1) receptor antagonist in preventing hepatic fibrosis caused by CCl(4) administration in rats;to investigate whether or not there are expression of AT 1 receptors on hepatic stellate cells; and to observe the effect of Ang II on proliferation and ECM synthesis of cultured HSCs.METHODS:Studies were conducted in male Sprague-Dawley rats. Except for the hepatofibrotic model group and the control group, in three treated groups, either enalapril (5mg/kg), or losartan (10mg/kg), or enalapril + losartan were given to the fibrotic rats by daily gavage, and saline vehicle was given to model and normal control rats. After 6 weeks, liver fibrosis was assessed directly by hepatic morphometric analysis, which has been considered the gold standard for the quantification of fibrosis. The expressions of AT 1 receptors and (alpha-mooth muscle actin,alpha-SMA) in liver tissue or isolated hepatic stellate cells (HSCs) were detected by immunohistochemical techniques. The effect of Ang II on HSC proliferation was determined by MTT method. Effect of Ang II on collagen synthesis of HSCs was determined by (3)H-proline incorporation.RESULTS:Contrasted to the fibrosis in rats of the model group, groups of rats treated with either enalapril or losartan, or a combination of two drugs showed a limited expansion of the interstitium (4.23 plus minus 3.70 vs 11.22 plus minus 4.79, P<0.05), but no difference was observed among three treated groups (5.38 plus minus3.43, 4.96 plus minus 2.96, 4.23 plus minus 2.70, P>0.05). Expression of AT 1 receptors was found in fibrotic interstitium of fibrotic rats, whereas in normal control rats they were limited to vasculature only to a very slight degree. AT 1 receptors were also expressed on activated HSCs in the culture. At concentrations from 10(-9) to 10(-5)mol/L, Ang II stimulated HSC proliferation in culture in a dose dependent manner. Increasing Ang II concentrations produced corresponding increases in (3)H-proline incorporation. Differences among groups were significant.CONCLUSION:Angiotensin converting enzyme inhibitors and AT 1 blocker may slow the progression of hepatic fibrosis;activated HSCs express AT 1 receptors, and Ang II can stimulate the proliferation and collagen synthesis of HSCs in a dose-dependent manner; and activation of RAS may be related to hepatic fibrogenesis induced by CCl(4).

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