The role of oxymatrine in regulating TGF-ß1 in rats with hepatic fibrosis

Abstract Purpose: To investigate whether oxymatrine (OMT) prevents hepatic fibrosis in rats by regulating liver transforming growth factor β1 (TGF-β1) level. Methods: Hepatic fibrosis was induced in rats by thioacetamide (TAA). Blood was collected at the end of week 12 to determine the levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), and glutathione (GSH). Changes in liver tissue were observed after hematoxylin-eosin (HE) staining. Results: Fibrosis was confirmed by Masson's collagen staining. Liver TGF-β1 level was determined by ELISA. OMT significantly reduced serum ALT and AST but increased GSH levels in rats with hepatic fibrosis. Moreover, it significantly improved liver histology in rats with TAA-induced hepatic fibrosis. It significantly decreased liver TGF-β1 level compared to that in the untreated group. It also significantly reduced collagen deposition in rats. Conclusion: Oxymatrine is effective in protecting rats from thioacetamide-induced hepatic fibrosis by regulating TGF-β1 expression.

Alteration of taste buds in experimental cirrhosis. Is there correlation with human hypogeusia? / Alteração de paladar em um modelo experimental de cirrose. Existe correlação com hipogeusia humana?

ABSTRACT Background The inherent complications of cirrhosis include protein-calorie malnutrition and micronutrient deficiencies.Changes in taste are detrimental to the nutritional status, and the mechanism to explain these changes is not well documented in the cirrhotic patients. Objective To evaluate the taste buds of cirrhotic rats. Methods Fourteen male Wistar rats were evaluated. After 16 weeks, the liver was removed to histologically diagnose cirrhosis, and blood was collected to perform liver integrity tests. The tongue was removed for histological examination and immunohistochemistry using antibodies against protein gene product PGP 9.5 and the sweet taste receptors T1R2 and T1R3. Morphological changes were determined by scanning electron microscopy. Serum zinc levels were measured. Results The cirrhotic animals, but not the control animals, exhibited zinc deficiency. In both groups, there was positive immunoreactivity for type II and III cells and T1R2 receptors. The cirrhotic animals had no immunoreactivity for T1R3 receptors. Scanning electron microscopy analysis of the cirrhotic group revealed a uniform tapering of the gustatory papillae. Conclusion In conclusion the experimental cirrhosis model mimicked the biochemical and histological parameters of human cirrhosis, therefore enabling a study of the gustatory papillae and taste buds.

RESUMO Contexto As complicações inerentes de cirrose incluem a desnutrição proteico-calórica e deficiências de micronutrientes. Alterações no paladar são prejudiciais para o estado nutricional e o mecanismo para explicar essas mudanças não é bem documentada nos pacientes cirróticos. Objetivo Avaliar as papilas gustativas de ratos cirróticos. Métodos Foram avaliados 14 ratos Wistar machos. Após 16 semanas, o fígado foi removido para diagnosticar histologicamente cirrose, e o sangue foi colhido para efetuar testes de integridade hepática. A língua foi removida para exame histológico e imuno-histoquímica utilizando anticorpos contra o gene da proteína PGP 9.5 e os receptores de sabor doce T1R2 e T1R3. As alterações morfológicas foram determinadas por microscopia eletrônica de varredura e os níveis de zinco no soro foram medidos. Resultados Os animais cirróticos, em relação aos animais controle, apresentaram deficiência de zinco significativa. Em ambos os grupos, houve imunorreatividade positiva para o tipo II e células III e receptores T1R2. Os animais cirróticos não tinham imunoreactividade para receptores T1R3. Microscopia eletrônica de varredura do grupo cirrótico revelou um afilamento uniforme das papilas gustativas. Conclusão O modelo de cirrose experimental imitou os parâmetros bioquímicos e histológicos de cirrose humana, portanto, permitindo um estudo das papilas gustativas e paladar.

Thalidomide Accelerates the Degradation of Extracellular Matrix in Rat Hepatic Cirrhosis via Down-Regulation of Transforming Growth Factor-beta1

PURPOSE: The degradation of the extracellular matrix has been shown to play an important role in the treatment of hepatic cirrhosis. In this study, the effect of thalidomide on the degradation of extracellular matrix was evaluated in a rat model of hepatic cirrhosis. MATERIALS AND METHODS: Cirrhosis was induced in Wistar rats by intraperitoneal injection of carbon tetrachloride (CCl4) three times weekly for 8 weeks. Then CCl4 was discontinued and thalidomide (100 mg/kg) or its vehicle was administered daily by gavage for 6 weeks. Serum hyaluronic acid, laminin, procollagen type III, and collagen type IV were examined by using a radioimmunoassay. Matrix metalloproteinase-13 (MMP-13), tissue inhibitor of metalloproteinase-1 (TIMP-1), and alpha-smooth muscle actin (alpha-SMA) protein in the liver, transforming growth factor beta1 (TGF-beta1) protein in cytoplasm by using immunohistochemistry and Western blot analysis, and MMP-13, TIMP-1, and TGF-beta1 mRNA levels in the liver were studied using reverse transcriptase polymerase chain reaction. RESULTS: Liver histopathology was significantly better in rats given thalidomide than in the untreated model group. The levels of TIMP-1 and TGF-beta1 mRNA and protein expressions were decreased significantly and MMP-13 mRNA and protein in the liver were significantly elevated in the thalidomide-treated group. CONCLUSION: Thalidomide may exert its effects on the regulation of MMP-13 and TIMP-1 via inhibition of the TGF-beta1 signaling pathway, which enhances the degradation of extracellular matrix and accelerates the regression of hepatic cirrhosis in rats.

Cost of the Cervical Cancer Screening Program at the Mexican Social Security Institute / Costo del Programa de Detección Oportuna de Cáncer Cervical en el Instituto Mexicano del Seguro Social

Objective. To estimate the annual cost of the National Cervical Cancer Screening Program (CCSP) of the Mexican Institute of Social Security (IMSS). Materials and methods. This cost analysis examined regional coverage rates reported by IMSS. We estimated the number of cytology, colposcopy, biopsy and pathology evaluations, as well as the diagnostic test and treatment costs for cervical intraepithelial neoplasia grade II and III (CIN 2/3) and cervical cancer. Diagnostic test costs were estimated using a micro-costing technique. Sensitivity analyses were performed. Results. The cost to perform 2.7 million cytology tests was nearly 38 million dollars, which represents 26.1% of the total program cost (145.4 million). False negatives account for nearly 43% of the program costs. Conclusion. The low sensitivity of the cytology test generates high rates of false negatives, which results in high institutional costs from the treatment of undetected cervical cancer cases.

Objetivo. Estimar el costo anual del Programa Nacional de Detección Oportuna de Cáncer Cervical en el Instituto Mexicano del Seguro Social (IMSS). Material y métodos. Este análisis de costos examinó las distintas coberturas por región reportadas por el IMSS. Se estimó el número de citologías, colposcopías, biopsias y evaluaciones de patología y los costos de pruebas de diagnóstico y de tratamientos por neoplasia cervical intraepitelial de grado II y III (NIC 2/3) y cáncer cervical. Los costos de las pruebas de diagnóstico se estimaron utilizando una técnica de microcosteo. Se llevó a cabo un análisis de sensibilidad. Resultados. El costo de realizar 2.7 millones de citologías fue de 38 millones de dólares, lo que representa 26.1% del costo total del programa (145.4 millones). Los falsos negativos corresponden a casi 43% de los costos del programa. Conclusiones. La baja sensibilidad de la citología genera un alto número de falsos negativos que resultan en costos elevados para la institución por el tratamiento de estos casos no detectados.

Review of experimental models for inducing hepatic cirrhosis by bile duct ligation and carbon tetrachloride injection / Revisão de modelos experimentais de cirrose hepática induzida por ligadura do ducto biliar e por injeção de tetracloreto de carbono

PURPOSE: To present a review about a comparative study of bile duct ligation versus carbon tetrachloride Injection for inducing experimental liver cirrhosis. METHODS: This research was made through Medline/PubMed and SciELO web sites looking for papers on the content "induction of liver cirrhosis in rats". We have found 107 articles but only 30 were selected from 2004 to 2011. RESULTS: The most common methods used for inducing liver cirrhosis in the rat were administration of carbon tetrachloride (CCl4) and bile duct ligation (BDL). CCl4 has induced cirrhosis from 36 hours to 18 weeks after injection and BDL from seven days to four weeks after surgery. CONCLUSION: For a safer inducing cirrhosis method BDL is better than CCl4 because of the absence of toxicity for researches and shorter time for achieving it.

OBJETIVO: Apresentar revisão sobre estudo comparativo da indução de cirrose hepática (CH) experimental com a injeção de tetra-cloreto de carbono (CCl4) comparado à ligadura do ducto biliar (BDL). MÉTODOS: A pesquisa foi realizada nas bases de dados do Medline/PubMed e SciELO procurando trabalhos com as palavras indução de CH e ratos. Foram encontrados 107 artigos, mas somente 30 foram selecionados no período de 2004 à 2011. RESULTADOS: Os procedimentos mais comum para indução de CH em ratos foram a injeção de CCl4 e a BDL. O CCl4 induzia CH no período de 36 horas após a injeção e a DBL de sete dias à quatro semanas após a cirurgia. CONCLUSÃO: A BDL é o método mais seguro para indução de CH quando comparado a injeção de CCl4 pela ausência de toxicidade para os pesquisadores e o menor tempo para se obter a lesão hepática.

The effect of down-regulation of Smad3 by RNAi on hepatic stellate cells and a carbon tetrachloride-induced rat model of hepatic fibrosis

Searching for effective Smad3 gene-based gene therapies for hepatic fibrosis, we constructed siRNA expression plasmids targeting the rat Smad3 gene and then delivered these plasmids into hepatic stellate cells (HSCs). The effect of siRNAs on the mRNA levels of Smad2, Smad3, Smad4, and collagens I-α1, III-α1 and IV-α1 (Colα1, Col3α1, Col4α1, respectively) was determined by RT-PCR. Eighty adult male Sprague-Dawley rats were randomly divided into three groups. Twice a week for 8 weeks, the untreated hepatic fibrosis model (N = 30) and the treated group (N = 20) were injected subcutaneously with 40 percent (v/v) carbon tetrachloride (CCl4)-olive oil (3 mL/kg), and the normal control group (N = 30) was injected with olive oil (3 mL/kg). In the 4th week, the treated rats were injected subcutaneously with liposome-encapsulated plasmids (150 µg/kg) into the right liver lobe under general anesthesia once every 2 weeks, and the untreated rats were injected with the same volume of buffer. At the end of the 6th and 8th weeks, liver tissue and sera were collected. Pathological changes were assessed by a semi-quantitative scoring system (SSS), and a radioimmunoassay was used to establish a serum liver fibrosis index (type III procollagen, type IV collagen, laminin, and hyaluronic acid). The mRNA expression levels of the above cited genes were reduced in the HSCs transfected with the siRNA expression plasmids. Moreover, in the treated group, fibrosis evaluated by the SSS was significantly reduced (P < 0.05) and the serum indices were greatly improved (P < 0.01). These results suggest that Smad3 siRNA expression plasmids have an anti-fibrotic effect.

Antifibrotic effects of magnesium lithospermate B on hepatic stellate cells and thioacetamide-induced cirrhotic rats

Magnesium lithospermate B (MLB) is one of the major active components of Salvia miltiorrhizae. The anti-oxidative effects of Salvia miltiorrhizae have been previously reported. The aim of this study was to investigate the effect of purified MLB on hepatic fibrosis in rats and on the fibrogenic responses in hepatic stellate cells (HSCs). Hepatic fibrosis was induced in rats by intraperitoneal thioacetamide (TAA) injections over a period of 8 or 12 weeks. MLB was orally administered daily by gavage tube. Serum AST and ALT levels in TAA + MLB group were significantly lower than those in TAA only group at week 8. Hepatic fibrosis was significantly attenuated in TAA + MLB group than in TAA only group at week 8 or 12. Activation of HSCs was also decreased in TAA + MLB group as compared to TAA only group. Hepatic mRNA expression of alpha-smooth muscle actin (alpha-SMA), TGF-beta1, and collagen alpha1(I) was significantly decreased in TAA + MLB group as compared to TAA only group. Incubation with HSCs and MLB (> or =100 microM) for up to 48 h showed no cytotoxicity. MLB suppressed PDGF-induced HSC proliferation. MLB inhibited NF-kappaB transcriptional activation and monocyte chemotactic protein 1 (MCP-1) production in HSCs. MLB strongly suppressed H2O2-induced reactive oxygen species (ROS) generation in HSCs, and MLB inhibited type I collagen secretion in HSCs. We concluded that MLB has potent antifibrotic effect in TAA-treated cirrhotic rats, and inhibits fibrogenic responses in HSCs. These data suggest that MLB has potential as a novel therapy for hepatic fibrosis.

The effect of preconditioning on liver regeneration after hepatic resection in cirrhotic rats / 대한간학회지

BACKGROUND/AIMS: Ischemic preconditioning (IP) decreases severity of liver necrosis and has anti-apoptotic effects in previous studies using liver regeneration in normal rats. This study assessed the effect of IP on liver regeneration after hepatic resection in cirrhotic rats. METHODS: To induce liver cirrhosis, thioacetamide (300 mg/kg) was injected intraperitoneally into Sprague-Dawley rats twice per week for 16 weeks. Animals were divided into four groups: non-clamping (NC), total clamping (TC), IP, and intermittent clamping (IC). Ischemic injury was induced by clamping the left portal pedicle including the portal vein and hepatic artery. Liver enzymes alanine transaminase (ALT) and aspartate aminotransferase (AST) were measured to assess liver damage. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) staining for apoptosis and proliferating cell nuclear antigen (PCNA) staining for cell replication were also performed. RESULTS: Day-1 ALT and AST were highest in IP, however, levels in NC and IC were comparably low on days 1-7. There was no significant correlation of AST or ALT with experimental groups (P=0.615 and P=0.186). On TUNEL, numbers of apoptotic cells at 100x magnification (cells/field) were 31.8+/-24.2 in NC, 69.0+/-72.3 in TC, 80.2+/-63.1 in IP, and 21.2+/-20.8 in IC (P<0.05). When regeneration capacity was assessed by PCNA staining, PCNA-positive cells (cells/field) at 400x were 3.4+/-6.0 in NC, 16.9+/-69 in TC, 17.0+/-7.8 in IP and 7.4+/-7.6 in IC (P<0.05). CONCLUSIONS: Although regeneration capacity in IP is higher than IC, the liver is vulnerable to ischemic damage in cirrhotic rats. Careful consideration is needed in applying IP in the clinical setting.

Translocación bacteriana e infecciones en un modelo experimental de cirrosis en la rata / Bacterial translocation and infections in an experimental model

In summary the carbon tetrachloride/phenobarbital of cirrhosis in rats mimics human cirrhosis very closely, with development of ascites and SBP. This model shows us that bacterial overgrowth occurs as cirrhosis progresses and that bacterial translocation from the gut to extra-intestinal sites is part of the early pathogenesis of SBP. SID with norfloxacin dramatically reduced translocation and SBP at the expense of grampositive overgrowth and infection with gram-positives and colonization with strange gram negatives. SID with TMP-SMZ actually delayed development of ascites and prolonged survival.

Intestinal permeability assessed by 51Cr-EDTA in rats with CCl4 - induced cirrhosis / Permeabilidade intestinal ao 51-Cr-EDTA em ratos com cirrose induzida por CCl4

CONTEXT: The straight relationship between cirrhosis and impaired intestinal barrier has not been elucidated yet. OBJECTIVES: To verify 51Cr-EDTA-intestinal permeability in rats with CCl4-induced cirrhosis and controls. METHOD: Fifty male Wistar rats weighing 150-180 g were separated in three groups: 25 animals received CCl4 0.25 mL/kg with olive oil by gavage with 12 g/rat/day food restriction for 10 weeks (CCl4-induced cirrhosis); 12 received the same food restriction for 10 weeks (CCl4-non exposed). Other 13 rats received indomethacin 15 mg/kg by gavage as positive control of intestinal inflammation. RESULTS: The median (25-75 interquartile range) 51Cr-EDTA-IP values of cirrhotic and CCl4-non exposed rats were 0.90 percent (0.63-1.79) and 0.90 percent (0.60-1.52) respectively, without significant difference (P = 0.65). Animals from indomethacin group showed 51Cr-EDTA-IP, median 7.3 percent (5.1-14.7), significantly higher than cirrhotic and CCl4-non exposed rats (P<0.001). CONCLUSION: This study showed the lack of difference between 51Cr-EDTA-intestinal permeability in rats with and without cirrhosis. Further studies are necessary to better clarify the relationship between intestinal permeability and cirrhosis.

CONTEXTO: A relação direta entre cirrose e alterações na barreira intestinal ainda não foi devidamente esclarecida. OBJETIVO: Verificar a permeabilidade intestinal ao 51Cr-EDTA em ratos com cirrose induzida por tetracloreto de carbono (CCl4) e controles. MÉTODO: Cinquenta ratos Wistar machos pesando 150-180 g foram separados em três grupos: 25 animais receberam CCl4 0,25 mL/kg diluído em óleo de oliva por gavagem com restrição dietética de 12 g/rato/dia por 10 semanas (grupo cirrose induzida por CCl4); 12 receberam a mesma restrição dietética por 10 semanas (grupo não exposto ao CCl4). Outros 13 ratos receberam indometacina 15 mg/kg por gavagem como controle positivo de inflamação intestinal. RESULTADOS: A mediana (intervalo interquartil 25-75) dos valores de permeabilidade intestinal ao 51Cr-EDTA dos grupos cirrose induzida por CCl4 e não exposto ao CCl4 foram 0,90 por cento (0,63-1,79) e 0,90 por cento (0,60-1,52), respectivamente, sem significância estatística (P = 0,65). Os animais do grupo indometacina apresentaram uma mediana de permeabilidade intestinal ao 51Cr-EDTA de 7,3 por cento (5,1-14,7), sendo significativamente maior do que os grupos cirrose induzida por CCl4 e não exposto ao CCl4 (P<0,001). CONCLUSÃO: Este estudo não demonstrou diferenças entre a permeabilidade intestinal ao 51Cr-EDTA em ratos com e sem cirrose. Mais estudos são necessários para melhor esclarecer a relação entre a permeabilidade intestinal e cirrose.

Melatonin protects the liver and erythrocytes against oxidative stress in cirrhotic rats / Melatonina protege o fígado e eritrócitos do estresse oxidativo em ratos cirróticos

CONTEXT: Cirrhosis is a progressive chronic hepatopathy which constitutes an irreversible stage of liver dysfunction. OBJECTIVES: To evaluate the oxidative stress in the blood of cirrhotic rats treated with the antioxidant melatonin. METHODS: Cirrhosis was induced through inhalation of carbon tetrachloride. Liver integrity was evaluated by measuring serum enzymes, oxidative damage measured by lipoperoxidation, and antioxidant enzyme activity in erythrocytes. Lipoperoxidation, total nitrates, collagen, and histology by picrosirius staining were evaluated in the livers of these animals (n = 15), which were divided in three groups: control, carbon tetrachloride, and carbon tetrachloride + melatonin. Melatonin (20 mg/kg) was administered intraperitoneal from week 10 of carbon tetrachloride inhalation. In order to shorten the cirrhosis induction time, phenobarbital (0.3 g/L) was added to the animals' drinking water. RESULTS: A significant impairment in the liver integrity of melatonin-treated animals as compared to cirrhotic animals was observed. In rat erythrocytes and liver, lipoperoxidation was significantly increased in the cirrhotic rats as compared to controls, as measured through thiobarbituric acid reactive substances, and significantly decreased in melatonin-treated animals as compared to cirrhotic ones. In blood, a decrease in superoxide dismutase and glutathione peroxidase enzymes was detected in the cirrhotic group as compared to the control group, with increased superoxide dismutase activity when melatonin was administered. A reduction in the levels of total nitrates was detected in the hepatic tissue of the animals in the carbon tetrachloride group as compared to the control group and an increase of these levels in the carbon tetrachloride + melatonin group. As for hepatic collagen, we found a significant increase in the carbon tetrachloride group as compared to the controls and a regression of these values in the treated group. ...

CONTEXTO: A cirrose é uma hepatopatia crônica e progressiva que constitui estágio irreversível de disfunção hepática. É associada a alterações na circulação sistêmica. OBJETIVOS: Avaliar o estresse oxidativo no sangue de ratos cirróticos e tratados com antioxidante melatonina. MÉTODOS: A cirrose foi induzida através da inalação de tetracloreto de carbono. Foram avaliadas as provas de integridade hepática através das medidas das enzimas séricas, o dano oxidativo medido pela lipoperoxidação e a atividade das enzimas antioxidantes no eritrócito. No fígado desses animais, foram avaliados a lipoperoxidação, os nitratos totais, colágeno e histologia através de picrosíruis. Os animais (n = 15) foram divididos em três grupos experimentais: controle, tetracloreto de carbono e tetracloreto de carbono + melatonina. A melatonina foi administrada por via intraperitonial após a 10ª semana de inalação na concentração de 20 mg/kg. Com o objetivo de abreviar o tempo de indução, foi administrado para todos animais, fenobarbital na água de beber na concentração de 0,3 g/L. RESULTADOS: Observou-se redução significativa nas provas de integridade hepática nos animais tratados com melatonina, em relação aos animais cirróticos. Nos eritrócitos e fígados dos ratos, foi observado aumento significativo da lipoperoxidação nos ratos cirróticos em comparação com os controles, através da medida das substâncias que reagem ao ácido tiobarbitúrico, e redução nos animais tratados com melatonina. No sangue, observou-se diminuição dos valores das enzimas superóxido dismutase e glutationa peroxidase do grupo cirrótico em comparação ao grupo controle, elevando a atividade da superóxido dismutase quando administrada melatonina. Na avaliação dos nitratos totais, no tecido hepático, observou-se redução dos valores nos animais do grupo tetracloreto de carbono em comparação ao grupo CO e um aumento desses valores nos ratos do grupo tratado com melatonina. Na medida do colágeno ...

An ultrasound and histomorphological analysis of experimental liver cirrhosis in rats

We investigated whether liver injury by dual exposure to ethanol and carbon tetrachloride (EtOH + CCl4) for 15 weeks would persist after hepatotoxic agents were removed (EtOH + CCl4/8wR). After 15 weeks of hepatic injury with ethanol (5.5 percent, m/v) and carbon tetrachloride (0.05, mL/kg, ip), 5 of 11 female Wistar rats were sacrificed. The other 6 rats were maintained for an additional 8 weeks without hepatotoxic agents. Ultrasonography showed increased liver echogenicity and dilation of portal vein caliber in both groups (EtOH + CCl4: 0.22 ± 0.01 cm, P < 0.001; EtOH + CCl4/8wR: 0.21 ± 0.02 cm, P < 0.01) vs control (0.16 ± 0.02 cm). Histopathology showed regenerative nodules in both experimental groups. Histomorphometry revealed increased fibrosis content in both groups (EtOH + CCl4: 12.6 ± 2.64 percent, P < 0.001; EtOH + CCl4/8wR: 10.4 ± 1.36 percent, P < 0.05) vs control (2.2 ± 1.21 percent). Collagen types I and III were increased in groups EtOH + CCl4 (collagen I: 2.5 ± 1.3 percent, P < 0.01; collagen III: 1.3 ± 0.2 percent, P < 0.05) and EtOH + CCl4/8wR (collagen I: 1.8 ± 0.06 percent, P < 0.05; collagen III: 1.5 ± 0.8 percent, P < 0.01) vs control (collagen I: 0.38 ± 0.11 percent; collagen III: 0.25 ± 0.06 percent). Tissue transglutaminase increased in both groups (EtOH + CCl4: 66.4 ± 8 percent, P < 0.01; EtOH + CCl4/8wR: 58.8 ± 21 percent, P < 0.01) vs control (7.9 ± 0.8 percent). Cirrhosis caused by the association of CCl4-EtOH remained for at least 8 weeks after removal of these hepatotoxic agents. Ultrasound images can be a useful tool to evaluate advanced hepatic alterations.

Modelos experimentais para avaliação das alterações pulmonares na síndrome hepatopulmonar / Experimental models for assessment of pulmonary alterations in hepatopulmonary syndrome

OBJETIVO: O objetivo deste trabalho foi avaliar o melhor modelo experimental para observar alterações pulmonares que caracterizam a síndrome hepatopulmonar (SHP). MÉTODOS: Ratos machos Wistar, com peso médio de 250 g foram usados em quatro modelos experimentais: tetracloreto de carbono inalatório; tetracloreto de carbono intraperitoneal; ligadura parcial de veia porta; e ligadura de ducto biliar (LDB). Em todos os grupos os animais foram divididos em controle e experimental. Foram avaliadas as seguintes variáveis: transaminases; gasometria; lipoperoxidação por substâncias que reagem ao ácido tiobarbitúrico (TBARS) e por quimiluminescência; e atividade antioxidante da enzima superóxido dismutase (SOD). Foi feito também o exame anatomopatológico do pulmão. RESULTADOS: Observou-se diferenças significativas entre os grupos LDB controle e experimental: aspartato amino transferase (105,3 ± 43 vs. 500,5 ± 90,3 UI/L); alanino aminotransferase (78,75 ± 37,7 vs. 162,75 ± 35,4 UI/L); fosfatase alcalina (160 ± 20,45 vs. 373,25 ± 45,44 UI/L); pressão parcial de oxigênio (85,25 ± 8,1 vs. 49,9 ± 22,5 mmHg); e saturação de hemoglobina (95 ± 0,7 vs. 73,3 ± 12,07 por cento). A lipoperoxidação e a atividade antioxidante também demonstrou diferenças entre os dois grupos LDB (controle vs. experimental): TBARS (0,87 ± 0,3 vs. 2,01 ± 0,9 nmol/mg proteína); quimiluminescência (16008,41 ± 1171,45 vs. 20250,36 ± 827,82 cps/mg proteína); e SOD (6,66 ± 1,34 vs. 16,06 ± 2,67 UI/mg proteína). No exame anatomopatológico observou-se vasodilatação pulmonar no modelo de LDB. CONCLUSÕES: Os dados sugerem que o modelo de LDB pode ser usado para outros estudos envolvendo alterações hepáticas e suas relações com o estresse oxidativo e a SHP.

OBJECTIVE: The aim of this study was to identify the best experimental model in which to observe the pulmonary alterations characterizing hepatopulmonary syndrome (HPS). METHODS: Male Wistar rats, with mean weight of 250 g, were used in four experimental models: inhaled carbon tetrachloride; intraperitoneal carbon tetrachloride; partial portal vein ligation; and bile duct ligation (BDL). The animals in all groups were divided into control and experimental subgroups. The following variables were measured: transaminase levels; blood gases; lipoperoxidation, using thiobarbituric acid reactive substances (TBARS) and chemiluminescence; and levels of superoxide dismutase (SOD) anti-oxidant activity. Anatomopathological examination of the lung was also performed. RESULTS: There were statistically significant differences between the BDL control and BDL experimental groups: aspartate aminotransferase (105.3 ± 43 vs. 500.5 ± 90.3 IU/L); alanine aminotransferase (78.75 ± 37.7 vs. 162.75 ± 35.4 IU/L); alkaline phosphatase (160 ± 20.45 vs. 373.25 ± 45.44 IU/L); arterial oxygen tension (85.25 ± 8.1 vs. 49.9 ± 22.5 mmHg); and oxygen saturation (95 ± 0.7 vs. 73.3 ± 12.07 percent). Lipoperoxidation and antioxidant activity also differed significantly between the two BDL groups (control vs. experimental): TBARS (0.87 ± 0.3 vs. 2.01 ± 0.9 nmol/mg protein); chemiluminescence (16008.41 ± 1171.45 vs. 20250.36 ± 827.82 cps/mg protein); and SOD (6.66 ± 1.34 vs. 16.06 ± 2.67 IU/mg protein). The anatomopathological examination confirmed pulmonary vasodilatation in the BDL model. In the other models, there were no alterations that were characteristic of HPS. CONCLUSIONS: The data obtained suggest that the BDL model can be used in future studies involving hepatic alterations related to oxidative stress and HPS.

Seminiferous epithelium of rats with food restriction and carbon tetrachloride-induced cirrhosis

OBJECTIVE: Analyze the changes in the seminiferous epithelium in rats with carbon tetrachloride-induced cirrhosis (CCl4). MATERIALS AND METHODS: Forty-eight male Wistar rats aged 45-50 days, weighing 150-180 grams were used. Twenty-two rats underwent CCl4-induced cirrhosis with CCl4 0.25 mL/Kg weekly intragastrically once a week, during 10 weeks. Additionally, they had a 44 percent food restriction diet (Group 1). The control group was divided in two subgroups: 13 rats had a 44 percent food restriction diet and no CCl4 (Group 2) and 10 rats were not submitted to CCl4 or food restriction (Group 3). After 10 weeks, the rats were sacrificed and liver sections were collected for histological analysis. The testicular analysis was carried out to evaluate the frequency of tubules in stages VIII and XIV. RESULTS: The mean rates of stage VIII in animals with food restriction plus CCl4-induced cirrhosis and food restriction without CCl4 were significantly different from animals without either food restriction or CCl4 (18.1 ± 5.5 percent, 20.5 ± 2.5 percent and 13.4 ± 3.5 percent, respectively, p = 0.002). The mean rate of stage VIII in rats with cirrhosis was not significantly different from rats without cirrhosis (18.1 ± 5.5 percent and 17.4 ± 4.6 percent respectively). The mean frequency of stage XIV in rats with cirrhosis was significantly greater than rats without cirrhosis (4.7 ± 2.3 percent and 6.8 ± 1.9 percent respectively, p = 0.027). CONCLUSION: Animals with CCl4-induced cirrhosis and food restriction have shown alterations in spermatogenic cycle that were not seen in rats without CCl4-induced cirrhosis and food restriction.

Suppressive Effects of Antioxidant DA-9601 on Hepatic Fibrosis in Rats / 대한간학회지

BACKGROUND/AIMS: Oxidative stress is one of the important underlying mechanisms of hepatic fibrosis. DA-9601, the ethanol extracts of Artemisia asiatica, has been reported to possess strong antioxidative and cytoprotective actions. We tried to evaluate whether antioxidant can ameliorate dimethylnitrosamine (DMN)-induced hepatic fibrosis. METHODS: Rat hepatic fibrosis was induced by intraperitoneal administrations of 10 mg DMN six times. Additionally, rats of one group were started daily with DA-9601 30 mg/kg containing diets and another group was fed a pellet diet containing DA-9601 100 mg/kg. The immunohistochemical studies for collagen, alpha-smooth muscle actin (alpha-SMA), and fibronectin, the measurements of hepatic malondialdehyde (MDA) and collagens, and the changes of liver function profiles were performed. Hepatic stellate cells (HSC) were isolated and in vitro effects of DA-9601 on HSC activations were measured. RESULTS: DA-9601 significantly attenuated the loss of body weights (p<0.05), the reduction of liver wet weights (p<0.05), and the elevation of liver enzymes provoked by DMN administrations. DMN injections caused the severe fibrosis of portal tract, hepatic inflammation, and significant oxidative damages, but DA-9601 treatment significantly reduced the mean scores of hepatic fibrosis, the amounts of hepatic collagens, and hepatic MDA levels. The prominent decreases in the expressions of collagens type I and III, alpha-SMA, and fibronectin or hepatic inflammations were observed in DA-9601-treated groups dose-dependently and similar efficacy was also proven in in vitro HSC experiment. CONCLUSIONS: DA-9601 effectively protected rat liver tissues against the DMN-induced hepatic fibrosis. Antioxidant could be considered as a supplementary therapeutic for alleviating the hepatic fibrosis.

Cirrose experimental induzida pela inalaçao de tetracloreto de carbono: adaptaçao da técnica e avaliaçao da peroxidaçao lipídica / Experimental cirrhosis induced by carbon tetrachloride inhalation: adaptation of the technique and evaluation of lipid peroxidation

BACKGROUND: Long-term administration of carbon tetrachloride is an accepted experimental model to produce hepatic fibrosis. Oxidative stress has been postulated as a major molecular mechanism involved in carbon tetrachloride hepatotoxicity, where the reactive oxygen species play an important role in the pathogenesis of liver fibrosis. AIMS: This study was conducted to evaluate the effectiveness of an experimental model of hepatic cirrhosis induced by carbon tetrachloride inhalation as well as the importance of lipid peroxidation and the characteristics of the ascitic fluid in this model. METHODS: At first the hepatic histologic findings were assessed using the hematoxilineosin technique in different moments of carbon tetrachloride inhalation (5th, 7th, 9th, 12th weeks). Later, at the end of 15 weeks of the study the rats were divided in three groups (control; control + phenobarbital; and carbon tetrachloride + phenobarbital) for lipid peroxidation, ascitic fluid and histologic characteristics evaluation. For the lipid peroxidation analysis, thiobarbituric acid and QL techniques were used. Cytologic and bacteriologic parameters were analysed in the ascitic fluid. RESULTS: Cirrhosis was established in 100 per cent of carbon tetrachloride rats between the 12th and 15th weeks with an elevation in the lipid peroxidation carbon tetrachloride rats' livers. Ascitic fluid infection was observed in one of seven rats who has developed ascites. CONCLUSIONS: The carbon tetrachloride inhalation method developed in this study is effective in cirrhosis induction and ascites formation, and the carbon tetrachloride cirrhosis physiopathogenesis is probably related to the oxidative stress installation.

Decreased activity of hepatic alkaline protease in rats with carbon tetrachloride-induced liver cirrhosis.

To investigate the cause of accumulation of oxidised proteins in the livers of rats with carbon tetrachloride (CCl4) induced liver cirrhosis, the activity of alkaline protease (a high molecular weight, multisubunit cysteine proteinase) was determined in the cirrhotic livers. A significant decrease (P < 0.05) in the activity of hepatic alkaline protease was observed in the cirrhotic rats. Decreased activity of alkaline protease in the liver of cirrhotic rats may contribute to the accumulation of the oxidised proteins in the liver.

Hepatic fibrogenesis using chronic arsenic ingestion: studies in a murine model.

Chronic oral arsenic (As) ingestion has been alleged to cause hepatic fibrosis, non-cirrhotic portal fibrosis and cirrhosis of the liver. The present study was aimed to investigate if hepatic fibrogenesis and non-cirrhotic portal fibrosis (NCPF) is caused by arsenic. A significant increase in the hepatic protein and collagen was seen compared with controls; hepatic 4-hydroxyproline levels, indicative of fibrogenesis, were increased 4-14 folds with different dosages of arsenic compared to the controls. Hepatocellular necrosis and inflammation were negligible to mild in all the groups. None of the animals developed significant splenomegaly or features of non-cirrhotic portal hypertension. The results suggest that (i) prolonged oral arsenic ingestion in mice leads to significant hepatic fibrogenesis and collagen synthesis with minimal hepato-cellular injury; (ii) arsenic ingestion alone is unlikely to cause non-cirrhotic portal fibrosis or cirrhosis of liver. This murine model of arsenic feeding could be used for the evaluation of new antifibrotic agents for the liver.

Zinc counteracts experimentally-induced cirrhotic changes in rats.

In the present study, cirrhosis was induced in rats by administration of carbon tetra chloride for 8 weeks. In these animals ZnSo4 (equivalent to 100 and 200 micrograms of zinc) was administered orally and liver function tests and plasma zinc (Zn) estimations were carried out after 2 and 4 week intervals. The results revealed that Zn supplement counteracts cirrhotic changes in liver.

Rapeseed diet and hepatocyte hypertrophy: an experimental morphometric study

En un estudio previo se sugirió que la dieta suplementada con semilla de nabo evita el desarrollo de cirrosis experimental en la rata. En el presente trabajo se demostró por morfometría que la semilla de nabo produce hipertrofia de los hepatocitos. Este crecimiento, a juzgar por los hallazgos con microscopía electrónica, dependió fundamentalmente de la superficie citoplásmica, y en menor grado, del núcleo del hepatocito. La combinación de semilla de nabo con tetracloruro de carbono (CC14) produjo igualmente hipertrofia; sin embargo, aquélla no modificó el cuadro histológico de cirrosis inducida por CC14. El hecho de que la hipertrofia provocada por la semilla de nabo sea básicamente a expensas de organelos membranosos sustenta la idea de que algún ingrediente de ésta modifica la actividad de síntesis o degradación proteínica del hepatocito.