Novel Modulators of Alcohol Induced Metabolic and Liver Injury

酒精引起的代谢和肝损伤的新型调节剂

• 批准号: 8724156
• 负责人: RAJ M LAKSHMAN
• 金额: $ 10.6万
• 依托单位: GEORGE WASHINGTON UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-09-01 至 2016-07-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8724156
• 关键词: Acetylation; Address; Affect; Alcoholic Fatty Liver; Alcohols; Attenuated; Biochemical; Books; Chemistry; Chronic; Data; Deacetylation; Diet; Down-Regulation; Enzymes; Ethanol; Experimental Models; Fatty Acids; Fatty Liver; Fatty acid glycerol esters; Genes; Gluconeogenesis; Goals; Hepatic; Histopathology; Homeostasis; Injury; Lipids; Lipoproteins; Liver; MAP Kinase Gene; MAPK14 gene; Mediating; Messenger RNA; Metabolic; Methods; Molecular Biology; Mus; PPAR alpha; Pathway interactions; Peroxisome Proliferator-Activated Receptors; Peroxisome Proliferators; Phosphorylation; Physiology; Plasma; Play; Property; Proteins; Publications; Publishing; Records; Regulator Genes; Rodent; Role; Serum; Signal Pathway; Signaling Pathway Gene; Soy Proteins; Specificity; Testing; Time; Transcription Coactivator; Up-Regulation; Western Blotting; abstracting; alcohol abuse therapy; base; clinically relevant; fatty acid oxidation; lipid biosynthesis; liver injury; mouse model; novel; oxidation; oxidized lipid; prevent; problem drinker; receptor

Rationale: Chronic ethanol-induced down regulations of silence regulator gene 1 (SIRT1) and peroxisome proliferator receptor coactivator 1 (PGC1) 1 and up-regulation of PGC1beta affect hepatic lipid oxidation and lipogenesis leading to fatty liver and consequent injury. We show that dietary low omega3-fatty acids (omega3FA), but not high omega3FA, significantly decreased serum and liver lipids, while Soy Proteins (SP) had similar lipid lowering effects. Therefore, it is clinically relevant to prove that these two novel modulators attenuate alcohol-induced fatty liver and injury potentially by regulating these opposing PGC1alpha and PGC1beta signaling pathway genes. Preliminary Studies: Our rationales are based on our publication records (12 Publications, 1 Review article, 1 book & 21 Abstracts in the past 5 years), and on strong preliminary data that are summarized below: Low omega3FA & SP opposed the actions of chronic alcohol by (a) Reducing serum lipids with concomitant decreased fatty liver; (b) Attenuating the up-regulation of hepatic mRNAs of PGC1beta, SREBP1c and their target lipogenic pathway genes; (c) Preventing the down-regulation of hepatic mRNAs of SIRT1 and PGC11 and their target fatty acid oxidation pathway genes; (d) Preventing the hepatic increase in acetyl-PGC1alpha, its inactive form; (e) Restoring impaired hepatic fatty acid oxidation and gluconeogenesis; And (f) Restoring the hepatic level of PO4AMPK that was decreased by chronic alcohol treatment. (g) By Western blots, we demonstrated concomitant changes in levels of mRNAs of PGC1alpha and PGC1beta signaling pathway genes and the corresponding enzyme proteins caused by chronic alcohol. (h) That PGC11 plays a critical role in alcohol- induced fatty liver was demonstrated by dramatic increase in hepatic lipid score in PGC1alpha-KO mice. (i) PGC1beta seems to play a secondary role because PGC1beta-KO mice still developed alcoholic fatty liver albeit less pronounced than in PGC11-KO mice, presumably because of ethanol-mediated strong inhibition of PGC11. Specific aims: Based on these rationales and preliminary findings we will address the following specific aims: Specific Aim 1. Effects of omega3FA and SP on Chronic Ethanol-induced Increases in Plasma and Hepatic Lipids and Lipoproteins, AST, ALT and Their Correlation with Liver Histopathology. Specific Aim 2. Mechanisms of Actions of omega3FA and SP on Ethanol-induced Up-regulation of Hepatic Lipid Anabolic Transcriptional Coactivators, Lipogenic Genes and de novo Lipid Synthetic Rates. Specific Aim 3. Mechanisms of Actions of omega3FA & SP on Ethanol-induced Down-regulation of Hepatic Lipid Catabolic Transcriptional Coactivators, Lipid Oxidizing Genes & Fatty Acid Oxidation Rates. Methods of Approach: PI and his team will accomplish these specific aims by using rodents as experimental models with their expertise in molecular biology, immuno- and histo-chemistry and biochemical approaches. PI will also use PGC11-KO and PGC12-KOs mouse models to conclusively prove their specificities in the actions of ethanol, Low 3FA & SP via these signaling pathways in causing/preventing alcoholic fatty liver and injury.

基本原理：慢性乙醇诱导的沉默调节基因1（SIRT 1）和过氧化物酶体增殖物受体辅激活因子1（PGC 1）1的下调以及PGC 1 β的上调影响肝脏脂质氧化和脂肪生成，导致脂肪肝和随后的损伤。我们发现，膳食低ω 3-脂肪酸（ω 3FA），但不高ω 3FA，显着降低血清和肝脏脂质，而大豆蛋白（SP）有类似的降脂作用。因此，证明这两种新型调节剂可能通过调节这些相反的PGC 1 α和PGC 1 β信号通路基因来减轻酒精诱导的脂肪肝和损伤具有临床意义。初步研究：我们的理由是基于我们的出版记录（12篇出版物，1篇评论文章，1本书和21篇摘要，在过去5年），并在下面总结的强有力的初步数据：低ω 3FA和SP通过（a）降低血脂伴随脂肪肝减少而对抗慢性酒精的作用;（B）减弱PGC 1 β、SREBP 1c及其靶脂肪生成途径基因的肝mRNA的上调;（d）防止肝脏中乙酰-PGC 1 α（其非活性形式）的增加;（e）恢复受损的肝脏脂肪酸氧化和再生;（f）恢复因长期酒精治疗而降低的肝脏PO 4 AMPK水平。(g)通过Western印迹，我们证明了慢性酒精引起的PGC 1 α和PGC 1 β信号通路基因和相应酶蛋白的mRNA水平的伴随变化。(h)PGC 11在酒精诱导的脂肪肝中起关键作用，这通过PGC 1alpha-KO小鼠中肝脏脂质评分的显著增加来证明。(i)PGC 1 β似乎起次要作用，因为PGC 1 β-KO小鼠仍然发生酒精性脂肪肝，尽管不如PGC 11-KO小鼠明显，可能是因为乙醇介导的PGC 11强烈抑制。具体目标：基于这些基本原理和初步调查结果，我们将讨论以下具体目标：具体目标1。Omega 3FA和SP对慢性乙醇诱导的血浆和肝脏脂质和脂蛋白、AST、ALT升高的影响及其与肝脏组织学的相关性。具体目标2。omega 3FA和SP对乙醇诱导的肝脏脂质合成代谢转录辅激活因子、脂肪生成基因和脂质合成速率上调的作用机制具体目标3。omega 3FA和SP对乙醇诱导的肝脏脂质分解代谢转录辅激活因子、脂质氧化基因和脂肪酸氧化速率下调的作用机制。接近方法：PI和他的团队将通过使用啮齿动物作为实验模型，利用他们在分子生物学，免疫和组织化学以及生物化学方法方面的专业知识来实现这些特定目标。PI还将使用PGC 11-KO和PGC 12-科斯小鼠模型来最终证明其在乙醇、低3FA和SP通过这些信号通路引起/预防酒精性脂肪肝和损伤的作用中的特异性。