非酒精性脂肪性肝病的发病机制和动物模型课件.pptx
LuXiaozhao,Pathogenesis of NAFLD:Animal Models,非酒精性脂肪性肝病(nonalcoholic fatty liver disease,NAFLD)一系列除外酒精和其他明确损肝因素所致的,以肝实 质细胞脂肪堆积为主要特征的疾病。西方国家 人群发病率:成人20-30%,肥胖人群90%;其中,NASH 2-3%,肥胖人群37%;儿童3%,肥胖儿童57%。我国 仅次于病毒性肝炎的第二大慢性肝病。,NAFLD流行病学,肝细胞脂肪变性(hepatocellular steatosis)(单纯性脂肪肝)脂肪性肝炎(nonalcoholic steatohepatitis,NASH)肝纤维化(fibrosis)肝硬化(cirrhosis),NAFLD的自然病程,胰岛素抵抗(Insulin resistance)糖耐量异常糖尿病(Glucose intolerance or diabetes)中心性肥胖(Central obesity)高血压(Hypertension)血脂异常(Dyslipidaemia)肝细胞癌(hepatocellular carcinoma),NAFLD伴随相关疾病,The first hit脂质积累,脂肪变性(Steatosis),NAFLD发病机制一:The 2-hit hypothesis,The second hitinflammatorycytokinesadipokines,mitochondrial dysfunctionoxidative stress,NAFLD发病机制一:The 2-hit hypothesis,The key role of free fatty acids(FFA),NAFLD发病机制一:The 2-hit hypothesis,The third hit(a central feature of NAFLD pathogenesis)inadequate hepatocyte proliferation,NAFLD发病机制一:The 2-hit hypothesis,NAFLD肝脏中FFAs来源:lipolysis of adipose tissue(60%)dietary sources(15%)de novo lipogenesis(25%)NAFLD肝脏中FFAs的去向:-oxidation triglycerides(lipid droplets)VLDL,NAFLD发病机制二:Lipid accumulation/steatosis,NAFLD发病机制二:Lipid accumulation/steatosis,NAFLD发病机制三:Insulin resistance,NAFLD发病机制三:Insulin resistance,Insulin resistance,Lipolysis增加,SREBP-1c上调,FFAs合成增加,脂肪来源的FFAs增多,-oxidation减少,FFAs分解减少,NAFLD,NAFLD,FFAsTNF-aNF-kBJNK1SOCSCYP2E1DAG,抑制insulin受体活性抑制IRS磷酸化级联,Insulin resistance,NAFLD发病机制四:Inflammation/steatohepatitis,Inflammatory cytokines and FFA,HFD induced steatosis(murine models),NF-kB,FFAs,TNF-IL-6IL-1,NAFLD,Insulin resistance,NAFLD发病机制四:Inflammation/steatohepatitis,Adipokines,Leptin:抑制食欲,增加能量分解代谢,抑制脂肪合成增加炎症促进纤维化肥胖和NAFLD患者血清中水平上调,Leptin resistance,Adiponectin:抗炎增加胰岛素敏感性肥胖和NAFLD患者中水平下调,NAFLD发病机制四:Inflammation/steatohepatitis,Oxidative stress and mitochondrial dysfunction,NAFLD,FFAs overload,ROS,oxidative stress,Activation of inflammatory pathways,Mitochondrial damage,NAFLD发病机制四:Inflammation/steatohepatitis,ER stress and bacterial overgrowth,ER stress,Hyperinsulinaemia hyperlipidaemia,IRinflammation apoptosis Mitochondrial dysfunction,Small intestinal bacterial overgrowth,lipopolysaccharides,inflammation,