Bhat Adil, Das Sukanta, Yadav Gaurav, Chaudhary Sudrishti, Vyas Ashish, Islam Mojahidul, Gupta Abhishak C, Bajpai Meenu, Maiwall Rakhi, Maras Jaswinder Singh, Sarin Shiv K
Department of Molecular and Cellular Medicine Institute of Liver and Biliary Sciences New Delhi India.
Department of Transfusion Medicine Institute of Liver and Biliary Sciences New Delhi India.
Hepatol Commun. 2019 Nov 23;4(1):50-65. doi: 10.1002/hep4.1440. eCollection 2020 Jan.
Hyperoxidized albumin promotes inflammation and modulates several immune cells in severe alcoholic hepatitis (SAH). Platelets mediate inflammation by interacting with immune cells, endothelium, and other cells. The role of hyperoxidized albumin in platelet activation and alteration of platelet phenotype/functions is not known. Quantitative platelet proteomics performed in 10 patients with SAH was compared with 10 patients with alcoholic cirrhosis and 10 healthy controls, respectively. Dysregulated pathways were identified and validated in a separate cohort (n = 40). Healthy platelets were exposed to patient plasma or purified albumin or modified albumin (human-mercaptalbumin, humannonmercaptalbumin-1, and human nonmercaptalbumin ) in the presence or absence of CD36 blockade, and platelet secretome was analyzed. Two hundred and two up-regulated proteins linked to platelet activation, complement regulation, lipid transportation, and 321 down-regulated proteins related to platelet hemostasis and coagulation (fold change ± 1.5, < 0.01) were identified. Blood transcription module enrichment showed an inflammatory phenotype of SAH platelet. Increased level of platelet factor-4, P-selectin, and soluble cluster of differentiation-40 ligand correlated with severity (Model for End-Stage Liver Disease score, r > 0.3, < 0.05) in SAH. Transcripts linked to platelet activation (increased) and granular secretions (decreased in SAH) correlated with disease severity. SNARE (soluble-N-ethylmaleimide-sensitive-factor-activating-protein-receptor) complex proteins (SNAP-23 [synaptosomal-associated protein 23] and VAMP-8 [vesicle-associated membrane protein 3]) were down-regulated in SAH platelets ( < 0.05). stimulation of healthy platelets showed enhanced activation with patient plasma, or purified albumin-treatment blocking of CD36 blunted this effect ( < 0.05). modified albumin (primarily nonmercaptalbumin-human nonmercaptalbumin 2 [HNA2; 1 mg/mL]) showed high activation and aggregation and intracellular reactive oxygen species production in healthy platelets ( < 0.05), which significantly reduced after CD36 neutralization. Platelet secretome showed reduced inflammatory mediators and increased repair proteins. Hyperoxidized albumin triggers platelet activation (possibly through the CD36 receptor), promotes inflammation and oxidative stress, and contributes to disease severity in patients with SAH.
高氧化白蛋白可促进炎症反应，并调节重症酒精性肝炎（SAH）中的多种免疫细胞。血小板通过与免疫细胞、内皮细胞及其他细胞相互作用来介导炎症反应。高氧化白蛋白在血小板活化及血小板表型/功能改变中的作用尚不清楚。分别对10例SAH患者、10例酒精性肝硬化患者及10名健康对照者进行定量血小板蛋白质组学研究。在另一队列（n = 40）中对失调的信号通路进行了鉴定和验证。将健康血小板置于患者血浆、纯化白蛋白或修饰白蛋白（人巯基白蛋白、人非巯基白蛋白-1和人非巯基白蛋白）中，存在或不存在CD36阻断剂，然后分析血小板分泌组。鉴定出202种与血小板活化、补体调节、脂质转运相关的上调蛋白，以及321种与血小板止血和凝血相关的下调蛋白（变化倍数±1.5，<0.01）。血液转录模块富集显示SAH血小板具有炎症表型。SAH患者中血小板因子-4、P-选择素和可溶性分化簇40配体水平升高与疾病严重程度相关（终末期肝病模型评分，r>0.3，<0.05）。与血小板活化相关的转录本（升高）和颗粒分泌相关的转录本（SAH中降低）与疾病严重程度相关。SAH血小板中SNARE（可溶性N-乙基马来酰亚胺敏感因子激活蛋白受体）复合体蛋白（SNAP-23 [突触体相关蛋白23]和VAMP-8 [囊泡相关膜蛋白3]）下调（<0.05）。用患者血浆或纯化白蛋白处理健康血小板显示活化增强，CD36阻断可减弱这种效应（<0.05）。修饰白蛋白（主要是非巯基白蛋白-人非巯基白蛋白2 [HNA2；1 mg/mL]）可使健康血小板出现高活化、聚集及细胞内活性氧生成增加（<0.05），CD36中和后显著降低。血小板分泌组显示炎症介质减少，修复蛋白增加。高氧化白蛋白触发血小板活化（可能通过CD36受体），促进炎症和氧化应激，并导致SAH患者疾病严重程度增加。
