Aziz-Seible Razia S, McVicker Benita L, Kharbanda Kusum K, Casey Carol A
Razia S Aziz-Seible, Department of Biochemistry and Molecular Biology, University of Nebraska Medical Center, 985870 Nebraska Medical Center, Omaha, NE 68198-5870, United States.
World J Hepatol. 2011 Feb 27;3(2):45-55. doi: 10.4254/wjh.v3.i2.45.
To examine the consequences of cellular fibronectin (cFn) accumulation during alcohol-induced injury, and investigate whether increased cFn could have an effect on hepatocytes (HCs) by producing factors that could contribute to alcohol-induced liver injury.
HCs were isolated from rats fed a control or ethanol liquid diet for four to six weeks. Exogenous cFn (up to 7.5 μg/mL) was added to cells cultured for 20 h, and viability (lactate dehydrogenase,LDH), apoptosis (caspase activity) and secretion of proinflammatory cytokines (tumor necrosis factor alpha, TNF-α and interleukin 6 IL-6), matrix metalloproteinases (MMPs) and their inhibitors (tissue inhibitors of metalloproteinases, TIMPs) was determined. Degradation of iodinated cFn was determined over a 3 h time period in the preparations.
cFn degradation is impaired in HCs isolated from ethanol-fed animals, leading to its accumulation in the matrix. Addition of exogenous cFn did not affect viability of HCs from control or ethanol-fed animals, and apoptosis was affected only at the higher concentration. Secretion of MMPs, TIMPs, TNF-α and IL-6, however, was increased by exogenously added cFn, with HCs from ethanol-fed animals showing increased susceptibility compared to the controls.
These results suggest that the elevated amounts of cFn observed in alcoholic liver injury can stimulate hepatocytes to produce factors which promote further tissue damage.
研究酒精性损伤过程中细胞纤连蛋白（cFn）积累的后果，并探讨cFn增加是否通过产生可能导致酒精性肝损伤的因子而对肝细胞（HCs）产生影响。
从喂食对照或乙醇液体饮食四至六周的大鼠中分离出肝细胞。将外源性cFn（高达7.5μg/mL）添加到培养20小时的细胞中，测定细胞活力（乳酸脱氢酶，LDH）、细胞凋亡（半胱天冬酶活性）以及促炎细胞因子（肿瘤坏死因子α，TNF-α和白细胞介素6，IL-6）、基质金属蛋白酶（MMPs）及其抑制剂（金属蛋白酶组织抑制剂，TIMPs）的分泌。在3小时的时间段内测定碘化cFn的降解情况。
从喂食乙醇的动物中分离出的肝细胞中cFn降解受损，导致其在基质中积累。添加外源性cFn不影响来自对照或喂食乙醇动物的肝细胞活力，仅在较高浓度下细胞凋亡受到影响。然而，外源性添加的cFn增加了MMPs、TIMPs、TNF-α和IL-6的分泌，与对照组相比，来自喂食乙醇动物的肝细胞显示出更高的易感性。
这些结果表明，在酒精性肝损伤中观察到的cFn含量升高可刺激肝细胞产生促进进一步组织损伤的因子。
