霉酚酸酯对脓毒症肝损伤的保护作用

Protective effect of mycophenolate mofetil for hepatic injury during sepsis

目的:探讨霉酚酸酯(mycophenolate mofetil,MMF)对脓毒症小鼠肝脏的保护作用。方法:将48只雄性Balb/c小鼠随机分为脓毒症模型组、MMF预处理[10 mg/(kg·d),2 d]的脓毒症模型组。两组分别于造模后1 h、6 h和24 h及假手术后检测丙氨酸转氨酶(alanine aminotransferase,ALT)水平并行肝脏HE染色及病理评分。采用Western印迹法检测自噬相关蛋白LC3Ⅰ/Ⅱ表达并观察7 d存活率。结果:与假手术组相比,脓毒症小鼠造模后6 h和24 h病理评分显著增高[(3.17±0.75)比(0.50±0.55)](P<0.000 1),[(2.67±0.82)比(0.50±0.55)](P<0.000 1);6和24 h血清ALT也显著升高[(1 077.80±188.80)比(120.70±40.90)],(P<0.000 1),[(432.20±154.80)比(120.70±40.90)](P<0.01)。预先给予MMF可显著降低以上指标:6 h病理评分降低[(3.17±0.75)比(2.17±0.75)](P<0.05),6 h和24 h血清ALT水平也都降低[(1 077.80±188.80)比(597.30±299.10)](P<0.05),[(432.20±154.80)比(179.60±45.80)](P<0.05);提高存活率(13.3%,53.3%,P<0.05),同时LC3Ⅱ蛋白表达升高。结论 :MMF可显著减轻脓毒症肝损伤,诱导自噬增加是其可能作用机制之一。

Objective To study the effect of mycophenolate mofetil（MMF） on liver function in mice with sepsis.Methods Forty-eight Balb/c mices were randomly divided into sepsis group and MMF sepsis group by sepsis model with MMF pretreatment. The sepsis model was induced by cecal ligation and puncture（CLP）. MMF was given by intraperitoneal injection at a dose of 10 mg/（kg·d） for 2 consecutive days before CLP. The serum and liver tissue were collected after sham operation（sham group） and at 1 h, 6 h and 24 h after CLP（1 h group, 6 h group, 24 h group）. The serum level of ALT as indicator of liver function was tested. Pathological examination was done and injury scores were evaluated by hematoxylin and eosin stain. Protein LC3 Ⅰ/Ⅱ which was associated with autophagy was analyzed by Western blot. Survival was determined for 7 days after CLP. Results Comparing with sham group, the injury scores of both 6 h group and24 h group were significantly elevated [（3.17±0.75） vs（0.50±0.55）]（P〈0.000 1）, [（2.67±0.82） vs（0.50±0.55）]（P〈0.000 1）respectively. The serum levels of ALT of both 6 h group and 24 h group also were significantly elevated [（1077.80 ±188.80）vs（120.70±40.90）]（P〈0.000 1）, [（432.20±154.80） vs（120.70±40.90）]（P〈0.01） respectively. The pretreatment of MMF significantly decreased the injury scores of 6 h group[（3.17±0.75） vs（2.17±0.75）]（P〈0.05） and serum levels of ALT of both 6h group and 24 h group [（1077.80 ±188.80） vs（597.30±299.10）]（P〈0.05）, [（432.20 ±154.80） vs（179.60±45.80）]（P〈0.05）respectively. Seven day survival rate was improved（13.3%, 53.3%, P〈0.05） while the expression of LC3Ⅱ protein was significantly elevated. Conclusions MMF might ameliorate sepsis associated hepatic damage probably through the effect of activation of autophagic process.