京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第19600号 / 医博第4107号 / 新制||医||1014(附属図書館) / 32636 / 京都大学大学院医学研究科医学専攻 / (主査)教授 萩原 正敏, 教授 清水 章, 教授 川上 浩司, 教授 瀬原 淳子 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DFAM

Peroxisome proliferator-activated receptor alpha (PPARa) and delta (PPARd) belong to the nuclear receptor superfamily. PPARa is a target of lipid-lowering drugs and PPARd promotes fatty acid utilization and is a promising anti-diabetic drug target. However, evidence is growing that PPARd-agonism can stimulate fat accumulation in liver, which may aggravate the toxic situation in diabetics. The aim of the study was to characterise the hepatic transcriptional and lipid response of humanized mouse models to PPARd-agonists. In our studies of mice conditionally-expressing human PPARd (hPPARd), or the dominant-negative derivative of hPPARd (hPPARd?AF2) or wild-type animals, we demonstrated that GW501516, a potent PPARd activator, promoted up-regulation of the genes involved in lipid turnover, stimulated significant weight loss and promoted hepatic steatosis in these mouse models. There was time-dependent accumulation of hepatic triglycerides observed in wild-type and in conditionally-expressing hPPARd mice fed a diet containing PPARd synthetic ligand. This was not seen in animals conditionally-expressing hPPARd?AF2, neither in PPARa-KO or PPARd-KO animals. Concurrently, activation of PPARd in humanised animals caused significant depletion, as compared with controls, of adipose tissue deposits when fed normal or high fat diet. This effect was completely absent in PPARa-KO or PPARd-KO mice, fed diet containing GW501516. Genome-wide transcriptional profiling of GW501516 effects in the livers of these different mouse strains was performed. In PPARa-KO mice fed PPARd-agonist, some direct PPARd target genes were still up-regulated, demonstrating that they are not sufficient for the observed phenotype. In addition the blood HDL-raising effects of GW501516 were preserved in the PPARa-KO mice. This suggests a novel finding that both PPARd and PPARa receptors are essential for GW501516-driven weight loss and hepatic steatosis, with PPARa working downstream of PPARd.

A Doença Hepática Gordurosa Não Alcoólica (DHGNA) é uma condição clínicopatológica comum, caracterizada por depósito de lipídeos no hepatócito do parênquima hepático. A esteatose hepática (EH) é um dos componentes da DHGNA e caracteriza-se pela presença de vacúolos de lipídeos, principalmente triacilgliceróis (triglicerídeos), dentro dos hepatócitos. Alterações na oxidação das gorduras no fígado ou redução na exportação de lipoproteínas de muito baixa densidade (VLDL) a partir do órgão são os principais mecanismos etiopatogênicos envolvidos com a EH. A patogênese da DHGNA é multifatorial e diversos fatores ou condições têm sido relacionados à predisposição para o seu desenvolvimento. Atualmente, diferentes tratamentos farmacológicos para DHGNA estão sendo propostos, mas ainda não há nenhum estudo comprobatório da sua eficácia. Objetiva-se avaliar os efeitos da suplementação da colina e do frutooligossacarídeo (FOS) na dieta de ratos Wistar, no modelo de esteatose hepática, induzido por dieta hiperglicídica. Foram utilizados 46 ratos machos, da raça Wistar adultos com peso variando entre 250 - 320 g, vindos do Biotério Central do Campus da USP Ribeirão Preto. Do lote inicial de animais foram distribuídos de forma aleatória nos diferentes grupos de estudo de I a IV, dependendo da indução ou não da esteatose. Considerou-se fase I o período correspondente a indução de esteatose e fase II quando se submeteu os animais a suplementação com nutrientes (Grupos III e IV), ou quando os animais receberam dieta padrão pós fase I (Grupo II) . Os animais do Grupo I (controle) receberam ração padrão do biotério que foi igual para todos os animais, sendo separado um lote da mesma ração para todo o experimento. Foi analisado as seguintes variáveis: Ingestão alimentar semanal, evolução do peso dos animais, nitrogênio urinário, amônia urinária, colesterol total e triacilgliceróis séricos, peso úmido de fígado e coração, nitrogênio e gordura tecidual, dosagem de vitamina E, malondialdeído (MDA) e glutationa no tecido hepático e análise histopatológica. Observamos que nenhum dos nutrientes empregados (colina e FOS) foi eficaz na redução da quantidade de gordura do fígado pela análise histológica. Nenhum dos nutrientes adicionados foi capaz de proteger o fígado da ação dos radicais livres, já que o MDA, um marcador indireto da geração do estresse oxidativo, manteve-se com valores elevados mesmo na fase de tratamento. Ocorreu diminuição dos níveis de triacilgliceróis em todos os grupos submetidos à indução de esteatose, do início ao final do experimento. O frutooligossacarídeo foi capaz de reduzir os níveis de colesterol sérico, em relação aos seus níveis basais, quando suplementado após indução de esteatose. / Non-alcoholic fatty liver disease (NAFLD) is a common clinical pathological condition characterized by fat accumulation in the the hepatic parenchyma hepatocyte. Liver steatosis (HS) is one of the components of NAFLD and is characterized by the presence of lipids vacuoles, mainly triacylglycerol, within the hepatocites. Alterations in fat oxidation in the liver or very low density proteins lipoproteins tranport from the organ are the main etiopatogenic mechanisms involved in HS. NAFLD patogeny is multifactor, thus several factors have been associated the propensity to develop it. Presently, many drug treatments for NAFLD are being suggested, however, there have been no studies that prove their efficacy so far. The aim of this study was to assess the effects of choline and fructooligosaccharide (FOS) suplementation in Wistar rats with HS induced by high glicid diet. Forty six adult male Wistar rats weighing between 250g and 320g from the USP (Ribeirão Preto-USP) central vivarium were used. They were divided randomly into different study groups from I to IV depending on whether steatosis would be induced or not. Phase I of the study was the period corresponding to steatosis induction and phase II was when the animals received nutrient suplementation (Groups III and IV) or when they received standard diet (Group II). Group I animals (control) received the usual vivarium food, which was the same for all of them. A certain amount of that same food was kept aside for the duration of the experiment. The following variables were analyzed: weekly food intake, weight gain, urine ammonia, urine nitrogen, total cholesterol and serum triacylglycerol, liver and heart humid weight, nitrogen and tissue fat, vitamin E, malondialdehyde (MDA) and glutathione content in the liver tissue and hitopathological analysis. As observed, neither of the nutrients (choline and FOS) was efficient in reducing the amount of fat in the liver. Neither of the nutrients added was able to protec the liver from free radicals, once the MDA, a indirect marker for oxidative stress generation, showed high levels even during the treatment phase. There was a reduction in triacylglycerol levels in all steatosis induced groups, from the beginning to the end of the experiment. Fructooligosaccharide was able to reduce the levels of serum cholesterol, in relation to its basal levels, when suplemented after steatosis induction.

A Doença Hepática Gordurosa Não Alcoólica (DHGNA) é uma condição clínicopatológica comum, caracterizada por depósito de lipídeos no hepatócito do parênquima hepático. A esteatose hepática (EH) é um dos componentes da DHGNA e caracteriza-se pela presença de vacúolos de lipídeos, principalmente triacilgliceróis (triglicerídeos), dentro dos hepatócitos. Alterações na oxidação das gorduras no fígado ou redução na exportação de lipoproteínas de muito baixa densidade (VLDL) a partir do órgão são os principais mecanismos etiopatogênicos envolvidos com a EH. A patogênese da DHGNA é multifatorial e diversos fatores ou condições têm sido relacionados à predisposição para o seu desenvolvimento. Atualmente, diferentes tratamentos farmacológicos para DHGNA estão sendo propostos, mas ainda não há nenhum estudo comprobatório da sua eficácia. Objetiva-se avaliar os efeitos da suplementação da colina e do frutooligossacarídeo (FOS) na dieta de ratos Wistar, no modelo de esteatose hepática, induzido por dieta hiperglicídica. Foram utilizados 46 ratos machos, da raça Wistar adultos com peso variando entre 250 - 320 g, vindos do Biotério Central do Campus da USP Ribeirão Preto. Do lote inicial de animais foram distribuídos de forma aleatória nos diferentes grupos de estudo de I a IV, dependendo da indução ou não da esteatose. Considerou-se fase I o período correspondente a indução de esteatose e fase II quando se submeteu os animais a suplementação com nutrientes (Grupos III e IV), ou quando os animais receberam dieta padrão pós fase I (Grupo II) . Os animais do Grupo I (controle) receberam ração padrão do biotério que foi igual para todos os animais, sendo separado um lote da mesma ração para todo o experimento. Foi analisado as seguintes variáveis: Ingestão alimentar semanal, evolução do peso dos animais, nitrogênio urinário, amônia urinária, colesterol total e triacilgliceróis séricos, peso úmido de fígado e coração, nitrogênio e gordura tecidual, dosagem de vitamina E, malondialdeído (MDA) e glutationa no tecido hepático e análise histopatológica. Observamos que nenhum dos nutrientes empregados (colina e FOS) foi eficaz na redução da quantidade de gordura do fígado pela análise histológica. Nenhum dos nutrientes adicionados foi capaz de proteger o fígado da ação dos radicais livres, já que o MDA, um marcador indireto da geração do estresse oxidativo, manteve-se com valores elevados mesmo na fase de tratamento. Ocorreu diminuição dos níveis de triacilgliceróis em todos os grupos submetidos à indução de esteatose, do início ao final do experimento. O frutooligossacarídeo foi capaz de reduzir os níveis de colesterol sérico, em relação aos seus níveis basais, quando suplementado após indução de esteatose. / Non-alcoholic fatty liver disease (NAFLD) is a common clinical pathological condition characterized by fat accumulation in the the hepatic parenchyma hepatocyte. Liver steatosis (HS) is one of the components of NAFLD and is characterized by the presence of lipids vacuoles, mainly triacylglycerol, within the hepatocites. Alterations in fat oxidation in the liver or very low density proteins lipoproteins tranport from the organ are the main etiopatogenic mechanisms involved in HS. NAFLD patogeny is multifactor, thus several factors have been associated the propensity to develop it. Presently, many drug treatments for NAFLD are being suggested, however, there have been no studies that prove their efficacy so far. The aim of this study was to assess the effects of choline and fructooligosaccharide (FOS) suplementation in Wistar rats with HS induced by high glicid diet. Forty six adult male Wistar rats weighing between 250g and 320g from the USP (Ribeirão Preto-USP) central vivarium were used. They were divided randomly into different study groups from I to IV depending on whether steatosis would be induced or not. Phase I of the study was the period corresponding to steatosis induction and phase II was when the animals received nutrient suplementation (Groups III and IV) or when they received standard diet (Group II). Group I animals (control) received the usual vivarium food, which was the same for all of them. A certain amount of that same food was kept aside for the duration of the experiment. The following variables were analyzed: weekly food intake, weight gain, urine ammonia, urine nitrogen, total cholesterol and serum triacylglycerol, liver and heart humid weight, nitrogen and tissue fat, vitamin E, malondialdehyde (MDA) and glutathione content in the liver tissue and hitopathological analysis. As observed, neither of the nutrients (choline and FOS) was efficient in reducing the amount of fat in the liver. Neither of the nutrients added was able to protec the liver from free radicals, once the MDA, a indirect marker for oxidative stress generation, showed high levels even during the treatment phase. There was a reduction in triacylglycerol levels in all steatosis induced groups, from the beginning to the end of the experiment. Fructooligosaccharide was able to reduce the levels of serum cholesterol, in relation to its basal levels, when suplemented after steatosis induction.

京都大学 / 0048 / 新制・課程博士 / 博士(医学) / 甲第18147号 / 医博第3867号 / 新制||医||1002(附属図書館) / 31005 / 京都大学大学院医学研究科医学専攻 / (主査)教授 川口 義弥, 教授 坂井 義治, 教授 千葉 勉 / 学位規則第4条第1項該当 / Doctor of Medical Science / Kyoto University / DGAM

Recently, persistent organic pollutants such as polychlorinated biphenyls (PCBs) were classified as “metabolic disruptors” for their suspected roles is altering metabolic and energy homeostasis through bioaccumulation in liver and adipose tissues. Among PCBs, a specific congener, 3,3',4,4',5-pentachlorobiphenyl (PCB126), is a potent arylhydrocarbon receptor (AhR) agonist and elicits toxicity similar to the classic dioxin, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD). PCB126 levels found in human blood are particularly associated with diabetes and nonalcoholic fatty liver disease (NAFLD) in humans, however the mechanisms are unclear. We hypothesized that the accumulation of PCB126 disrupts carbohydrate and lipid metabolism by altering the functions of liver and adipose tissues. Hence, our objective was to characterize PCB126 induced-metabolic disruption and the underlying molecular mechanisms that cause toxicity. Separate animal studies were performed using a rat model to understand the time- and dose-dependent effects after PCB126 administration. The chronology of PCB126 toxicity showed early decreases in serum glucose level at 9 h, worsened in a time-dependent way until the end of the study at 12 d. Lipid accumulation and the liver pathology also worsened over time between 3 d and 12 d post administration. These observed effects in the liver were also found to be dose-dependent. The decrease in serum glucose was a result of a decrease in the transcript levels of gluconeogenic and glycogenolytic enzymes, necessary for hepatic glucose production and hence the maintenance of steady glucose levels in the blood. Phosphoenolpyruvate carboxykinase (PEPCK-C), the rate limiting enzyme of gluconeogenesis, was found to be significantly decreased upon exposure to PCB126. The expression levels of peroxisome proliferator-activated receptor alpha (Pparα) and some of its targets involved in fatty acid oxidation were also found to be time and dose-dependently decreased upon exposure to PCB126. In an attempt to understand the molecular targets that may cause these dual effects on both gluconeogenic and fatty acid oxidation, we found that PCB126 significantly decreases phosphorylation of the cAMP response element-binding protein (CREB). CREB is a nuclear transcription factor that is activated in the liver through phosphorylation; to switch-on the transcription of enzymes that catalyze gluconeogenesis and fatty acid oxidation, in order to meet energy demands, especially during fasting. Further, to understand the toxicity of PCB126 on adipose tissue, a human pre-adipocyte model that can be differentiated into mature adipocytes was used. In these studies, we found that exposure of preadipocytes to PCB126 resulted in a significant reduction in their ability to differentiate into adipocytes. This results in decreased lipid accumulation in the adipocyte. Reduction in the differentiation by PCB126 was associated with down regulation in transcript levels of a key adipocyte transcription factor, PPARγ and its transcriptional targets necessary for adipogenesis and adipocyte function. These inhibitory effects of PCB126 on the regulation of PPARγ and the initiation of adipogenesis were mediated through activation of AhR. Overall, this work shows that PCB126 disrupts nutrient homeostasis through its effects on the function of target tissues; liver and adipose. PCB126 significantly alters the nutrient homeostasis through its effects on gluconeogenesis and fatty-acid oxidation necessary for glucose and energy regulation during fasting. In addition, PCB126 interrupts the storage functions of adipose tissue by inhibiting adipogenesis and thus disrupts lipid storage and distribution

This study used the non-alcoholic steatohepatitis activity index (NAI), presence of fibrosis and Mallory-Denk bodies (MDBs), and quantification of glucose regulated protein 78 (GRP78) messenger ribonucleic acid (mRNA) as indicators of steatohepatitis development and recovery in the American mink (Neovison vison). Mink were fasted for 0, 1, 3, 5, or 7 days, and one group re-fed 28 days post 7-day fast. Liver NAI indicated that moderate fatty liver developed after 5 days of fasting. Liver recovery was achieved after the re-feeding period. There was no evidence of fibrosis or MDB formation. Upregulation of GRP78 was observed by day 7 of fasting indicating endoplasmic reticulum stress. This effect was greater in females. Results suggest that liver steatosis did not advance to steatohepatitis within a 7-day fast. However, should the length of fast be increased the mink may be at risk. Results also show that liver recovery from simple fatty liver is possible.

O objetivo do presente estudo foi verificar o grau de resistência insulínica (RI) em pacientes infectados com o vírus da hepatite C (VHC) genótipo 1 versus genótipo 3. Foi incluído um total de 44 pacientes com hepatite crônica C, sendo 23 pacientes infectados com genótipo 1 e 21 pacientes infectados com genótipo 3. Nenhum paciente incluído tinha fatores de risco para Síndrome Metabólica e não foram submetidos a tratamento antiviral prévio. Trinta pacientes eram homens (68%). A média de idade em anos na amostra global foi de 47,5±9,1. Quanto ao genótipo do VCH, 23 pacientes (52%) tinham genótipo 1 e 21 (48%) genótipo 3. O grau de esteatose hepática (EH) entre 5% e 66% foi encontrado em 35 dos 44 pacientes. Não houve diferença significativa entre os genótipos 1 e 3 do VHC. Quanto aos níveis de colesterol total, colesterol HDL, colesterol LDL e as transaminases, não houve diferenças significativas entres os genótipos em estudo. A média do Índice de Massa Corporal (IMC) na amostra global foi de 25±1,8. A prevalência de resistência insulínica, medida pelo teste de HOMA (Modelo de avaliação de homeostase), foi verificada em 27 pacientes (61%). A média do HOMA entre os genótipos não atingiu diferença significativa. Fibrose moderada e severa foi encontrada em 14 (38%) dos 37 pacientes com esteatose hepática e em apenas 2 (27%) dos 7 sem esteatose hepática. A correlação entre resistência insulínica e fibrose hepática na população estudada foi estatisticamente significativa (P<0,001). Na análise de nossos dados, portanto, encontramos Resistência Insulínica em 61% dos 44 pacientes com hepatite crônica C sem fatores de risco para Doença Hepática Gordurosa Não Alcoólica (DHGNA). O grau de RI em pacientes, infectados com genótipo 1 versus genótipo 3 do VHC não foi estatisticamente diferente, tanto no que diz respeito à prevalência (65% versus 57%, respectivamente) quanto à magnitude (2,6 verus 2,8, respectivamente). Quanto à relação entre RI e EH nesses pacientes, verificou-se correlação positiva, havendo RI em 68% dos pacientes com EH versus 29% dos sem EH, sem atingir, no entanto, diferença estatisticamente significativa. Ao analisar a relação entre RI e fibrose hepática, houve diferença estatisticamente significativa em nossa casuística, sendo encontrada maior prevalência de fibrose intensa (F2 e F3 na classificação Metavir) nos 27 pacientes com RI em comparação com os 17 pacientes sem RI (56% versus 6%, respectivamente; P<0,01). / The main goal of this research was to verify the insulin resistance (IR) in patients infected with HCV genotype 1 versus genotype 3. A total of 44 patients with chronic hepatitis C were included in the study, 23 patients infected with genotype 1 and 21 patients infected with genotype 3. None of the patients had any risk for the Metabolic Syndrome and had not been submitted to any antiviral therapy before. 30 patients were males (68%). The age average was 47, 5 ± 9,1. About the VHC genotype, 23 (52%) had the genotype 1 and 21 (48%) had genotype 3. Liver steatosis grade (LS) was found in the range of 5% and 66% in 35 patients. There was no significant difference between the genotypes. About the total cholesterol levels, HDL-C and LDL-C, as well as the serum transaminases, there was no significant difference between the genotypes. The average of the body mass was 25 ± 1,8. The prevalence of insulin resistance (IR), measured by HOMA-IR test was verified in 27 patients (61%). The average of the HOMA-IR test between the genotypes was not statistically significant. Moderate and severe liver fibrosis was found in 14 patients (38%) out of the 37 patients with liver steatosis and only in 2 patients (29%) out of the 7 patients without steatosis. The relationship between insulin resistance and liver fibrosis in our sample was statistically significant (p<0,001). Analyzing our data, we found insulin resistance in 61% out of 44 patients with chronic hepatitis C without risks factors for non-alcoholic fatty liver disease (NAFLD). The amount of the insulin resistance between patients infected with genotype 1 versus genotype 3 of HCV was not statistically different both in the prevalence (65% versus 57% respectively) and in the magnitude (2,6 versus 2,8, respectively). About the relationship between IR and LS in our patients, there was a positive relationship, with IR in 68% of the patients with LS versus 29% of the patients without LS, but without a statistically significant difference. However, the relationship between IR and hepatic fibrosis showed a statistically significant difference, with a greater prevalence of intense fibrosis (F2 and F3 in METAVIR classification) in the 27 patients with IR compared to the 17 patients without IR (56% versus 6%, respectively - p< 0,01).

O objetivo do presente estudo foi verificar o grau de resistência insulínica (RI) em pacientes infectados com o vírus da hepatite C (VHC) genótipo 1 versus genótipo 3. Foi incluído um total de 44 pacientes com hepatite crônica C, sendo 23 pacientes infectados com genótipo 1 e 21 pacientes infectados com genótipo 3. Nenhum paciente incluído tinha fatores de risco para Síndrome Metabólica e não foram submetidos a tratamento antiviral prévio. Trinta pacientes eram homens (68%). A média de idade em anos na amostra global foi de 47,5±9,1. Quanto ao genótipo do VCH, 23 pacientes (52%) tinham genótipo 1 e 21 (48%) genótipo 3. O grau de esteatose hepática (EH) entre 5% e 66% foi encontrado em 35 dos 44 pacientes. Não houve diferença significativa entre os genótipos 1 e 3 do VHC. Quanto aos níveis de colesterol total, colesterol HDL, colesterol LDL e as transaminases, não houve diferenças significativas entres os genótipos em estudo. A média do Índice de Massa Corporal (IMC) na amostra global foi de 25±1,8. A prevalência de resistência insulínica, medida pelo teste de HOMA (Modelo de avaliação de homeostase), foi verificada em 27 pacientes (61%). A média do HOMA entre os genótipos não atingiu diferença significativa. Fibrose moderada e severa foi encontrada em 14 (38%) dos 37 pacientes com esteatose hepática e em apenas 2 (27%) dos 7 sem esteatose hepática. A correlação entre resistência insulínica e fibrose hepática na população estudada foi estatisticamente significativa (P<0,001). Na análise de nossos dados, portanto, encontramos Resistência Insulínica em 61% dos 44 pacientes com hepatite crônica C sem fatores de risco para Doença Hepática Gordurosa Não Alcoólica (DHGNA). O grau de RI em pacientes, infectados com genótipo 1 versus genótipo 3 do VHC não foi estatisticamente diferente, tanto no que diz respeito à prevalência (65% versus 57%, respectivamente) quanto à magnitude (2,6 verus 2,8, respectivamente). Quanto à relação entre RI e EH nesses pacientes, verificou-se correlação positiva, havendo RI em 68% dos pacientes com EH versus 29% dos sem EH, sem atingir, no entanto, diferença estatisticamente significativa. Ao analisar a relação entre RI e fibrose hepática, houve diferença estatisticamente significativa em nossa casuística, sendo encontrada maior prevalência de fibrose intensa (F2 e F3 na classificação Metavir) nos 27 pacientes com RI em comparação com os 17 pacientes sem RI (56% versus 6%, respectivamente; P<0,01). / The main goal of this research was to verify the insulin resistance (IR) in patients infected with HCV genotype 1 versus genotype 3. A total of 44 patients with chronic hepatitis C were included in the study, 23 patients infected with genotype 1 and 21 patients infected with genotype 3. None of the patients had any risk for the Metabolic Syndrome and had not been submitted to any antiviral therapy before. 30 patients were males (68%). The age average was 47, 5 ± 9,1. About the VHC genotype, 23 (52%) had the genotype 1 and 21 (48%) had genotype 3. Liver steatosis grade (LS) was found in the range of 5% and 66% in 35 patients. There was no significant difference between the genotypes. About the total cholesterol levels, HDL-C and LDL-C, as well as the serum transaminases, there was no significant difference between the genotypes. The average of the body mass was 25 ± 1,8. The prevalence of insulin resistance (IR), measured by HOMA-IR test was verified in 27 patients (61%). The average of the HOMA-IR test between the genotypes was not statistically significant. Moderate and severe liver fibrosis was found in 14 patients (38%) out of the 37 patients with liver steatosis and only in 2 patients (29%) out of the 7 patients without steatosis. The relationship between insulin resistance and liver fibrosis in our sample was statistically significant (p<0,001). Analyzing our data, we found insulin resistance in 61% out of 44 patients with chronic hepatitis C without risks factors for non-alcoholic fatty liver disease (NAFLD). The amount of the insulin resistance between patients infected with genotype 1 versus genotype 3 of HCV was not statistically different both in the prevalence (65% versus 57% respectively) and in the magnitude (2,6 versus 2,8, respectively). About the relationship between IR and LS in our patients, there was a positive relationship, with IR in 68% of the patients with LS versus 29% of the patients without LS, but without a statistically significant difference. However, the relationship between IR and hepatic fibrosis showed a statistically significant difference, with a greater prevalence of intense fibrosis (F2 and F3 in METAVIR classification) in the 27 patients with IR compared to the 17 patients without IR (56% versus 6%, respectively - p< 0,01).

O objetivo do presente estudo foi verificar o grau de resistência insulínica (RI) em pacientes infectados com o vírus da hepatite C (VHC) genótipo 1 versus genótipo 3. Foi incluído um total de 44 pacientes com hepatite crônica C, sendo 23 pacientes infectados com genótipo 1 e 21 pacientes infectados com genótipo 3. Nenhum paciente incluído tinha fatores de risco para Síndrome Metabólica e não foram submetidos a tratamento antiviral prévio. Trinta pacientes eram homens (68%). A média de idade em anos na amostra global foi de 47,5±9,1. Quanto ao genótipo do VCH, 23 pacientes (52%) tinham genótipo 1 e 21 (48%) genótipo 3. O grau de esteatose hepática (EH) entre 5% e 66% foi encontrado em 35 dos 44 pacientes. Não houve diferença significativa entre os genótipos 1 e 3 do VHC. Quanto aos níveis de colesterol total, colesterol HDL, colesterol LDL e as transaminases, não houve diferenças significativas entres os genótipos em estudo. A média do Índice de Massa Corporal (IMC) na amostra global foi de 25±1,8. A prevalência de resistência insulínica, medida pelo teste de HOMA (Modelo de avaliação de homeostase), foi verificada em 27 pacientes (61%). A média do HOMA entre os genótipos não atingiu diferença significativa. Fibrose moderada e severa foi encontrada em 14 (38%) dos 37 pacientes com esteatose hepática e em apenas 2 (27%) dos 7 sem esteatose hepática. A correlação entre resistência insulínica e fibrose hepática na população estudada foi estatisticamente significativa (P<0,001). Na análise de nossos dados, portanto, encontramos Resistência Insulínica em 61% dos 44 pacientes com hepatite crônica C sem fatores de risco para Doença Hepática Gordurosa Não Alcoólica (DHGNA). O grau de RI em pacientes, infectados com genótipo 1 versus genótipo 3 do VHC não foi estatisticamente diferente, tanto no que diz respeito à prevalência (65% versus 57%, respectivamente) quanto à magnitude (2,6 verus 2,8, respectivamente). Quanto à relação entre RI e EH nesses pacientes, verificou-se correlação positiva, havendo RI em 68% dos pacientes com EH versus 29% dos sem EH, sem atingir, no entanto, diferença estatisticamente significativa. Ao analisar a relação entre RI e fibrose hepática, houve diferença estatisticamente significativa em nossa casuística, sendo encontrada maior prevalência de fibrose intensa (F2 e F3 na classificação Metavir) nos 27 pacientes com RI em comparação com os 17 pacientes sem RI (56% versus 6%, respectivamente; P<0,01). / The main goal of this research was to verify the insulin resistance (IR) in patients infected with HCV genotype 1 versus genotype 3. A total of 44 patients with chronic hepatitis C were included in the study, 23 patients infected with genotype 1 and 21 patients infected with genotype 3. None of the patients had any risk for the Metabolic Syndrome and had not been submitted to any antiviral therapy before. 30 patients were males (68%). The age average was 47, 5 ± 9,1. About the VHC genotype, 23 (52%) had the genotype 1 and 21 (48%) had genotype 3. Liver steatosis grade (LS) was found in the range of 5% and 66% in 35 patients. There was no significant difference between the genotypes. About the total cholesterol levels, HDL-C and LDL-C, as well as the serum transaminases, there was no significant difference between the genotypes. The average of the body mass was 25 ± 1,8. The prevalence of insulin resistance (IR), measured by HOMA-IR test was verified in 27 patients (61%). The average of the HOMA-IR test between the genotypes was not statistically significant. Moderate and severe liver fibrosis was found in 14 patients (38%) out of the 37 patients with liver steatosis and only in 2 patients (29%) out of the 7 patients without steatosis. The relationship between insulin resistance and liver fibrosis in our sample was statistically significant (p<0,001). Analyzing our data, we found insulin resistance in 61% out of 44 patients with chronic hepatitis C without risks factors for non-alcoholic fatty liver disease (NAFLD). The amount of the insulin resistance between patients infected with genotype 1 versus genotype 3 of HCV was not statistically different both in the prevalence (65% versus 57% respectively) and in the magnitude (2,6 versus 2,8, respectively). About the relationship between IR and LS in our patients, there was a positive relationship, with IR in 68% of the patients with LS versus 29% of the patients without LS, but without a statistically significant difference. However, the relationship between IR and hepatic fibrosis showed a statistically significant difference, with a greater prevalence of intense fibrosis (F2 and F3 in METAVIR classification) in the 27 patients with IR compared to the 17 patients without IR (56% versus 6%, respectively - p< 0,01).