Protective effect of fibronectin for surgical stress and infection.

血浆纤维连接蛋白（Fn）具有广泛的生物学功能，涉及细胞粘附、运动、分化、凋亡、止血、伤口愈合、网状内皮系统功能和缺血性损伤。在这项研究中，我们研究了Fn对肝部分切除术后内毒素诱导的肝损伤、d -半乳糖胺(GalN)/脂多糖（LPS）诱导的小鼠暴发型肝衰竭、耐甲氧西林金黄色葡萄球菌（MRSA）引起的烧伤创面脓毒症和大鼠皮肤切口和腹腔切开术伤口愈合的影响。Fn可预防部分肝切除术后内毒素引起的肝损伤，至少部分是通过抑制剩余肝脏中炎症细胞因子、坏死和凋亡的产生。此外，Fn对GalN/ lps诱导的肝衰竭的保护机制涉及抑制核因子- kb激活，导致肿瘤坏死因子-a的下调和白细胞介素-10的上调，Bcl-xL的升高诱导凋亡信号的阻断。其次，Fn通过显著增强巨噬细胞吞噬作用来预防MRSA引起的烧伤创面败血症。最后，单次注射Fn显著增加了皮肤的断裂强度和腹壁的破裂压力。pFn组皮肤切口中羟脯氨酸的含量明显高于白蛋白组。在抗大鼠Fn血清降低Fn水平的大鼠中，与白蛋白对照注射相比，单次给药Fn显著增加了皮肤的断裂强度和腹壁的破裂压力。

Plasma fibronectin (Fn) has a broad range of biological functions involved in cellular adhesion, motility, differentiation, apoptosis, hemostasis, wound healing, reticuloendothelial system function, and ischemic injury. In this study, we examined the effects of Fn on endotoxin-induced liver injury after partial hepatectomy, D-galactosamine (GalN)/lipopolysaccharide (LPS)-induced fulminant liver failure in mice, burned wound sepsis caused by methicillin resistance Staphylococcus aureus (MRSA) and incisional wound healing in a rat skin incision and celiotomy. Fn prevented endotoxin-induced liver injury after partial hepatectomy, at least in part through the inhibition of production of inflammatory cytokines, necrosis and apoptosis in the remaining liver. Moreover, Fn protected against GalN/LPSinduced liver failure by a mechanism involving inhibition of nuclear factor-kB activation, which caused down-regulation of tumor necrosis factor-a and involved up-regulation of interleukin-10, and elevation of Bcl-xL induced a blockage of apoptotic signals. Secondly, Fn prevented burned wound sepsis caused by MRSA via significant enhancement of macrophage phagocytosis. Finally, a single injection of Fn significantly increased the breaking strength of the skin and the bursting pressure of the abdominal wall. The amount of hydroxyproline in the skin incisional wound with pFn was significantly higher than with an injection of albumin as control. In rats in whom Fn levels were decreased by anti-rat Fn serum, a single administration of Fn significantly increased the breaking strength of the skin and the bursting pressure of the abdominal wall, compared to a control injection of albumin.