三七总皂苷对慢性肾缺血肾间质纤维化的防治作用

目的观察三七总皂苷（PNS）对大鼠慢性肾缺血的保护作用及其机制。方法将大鼠随机分为假手术组，模型组及PNS治疗组。建立肾动脉狭窄肾缺血大鼠模型，分别于造模后第7，28，45．60天处死大鼠。观察肾间质病理形态学变化，应用免疫组织化学法检测肾小管－间质a—SMA在不同时间点的表达，放射免疫分析法检测血清IL-2的含量、EuSA检测血清血小板源性生长因子（PDGF）的含量。结果模型组肾间质纤维化的程度，肾小管上皮细胞及间质α—SMA的表达和血清PDGF的含量在各时间点明显高于假手术组（P〈0．01），PNS治疗组上述各项指标在不同时间点明显低于模型组（P〈0．05或P〈0．01）。模型组血清IL-2含量在7d时显著升高（P〈0．01），之后迅速下降到假手术组水平，45d时显著低于假手术组（P〈0．05）。PNS治疗组血清IL－2含量在7d时低于模型组（P〈0．05），其他时间点差别无统计学意义。结论PNS可能通过抑制肾小管间质细胞表型转化，降低细胞因子PDGF的水平和早期IL-2的水平减轻和改善慢性肾缺血肾间质纤维化。

Effects of Panax Notoginseng Saponins on Renal Interstitial Fibrosis in Rats with Chronic Renal Ischemia

Objective To study the protective and therapeutic effect of Panax notoginseng saponin （PNS） on chronic ischemic renal injury induced by renal artery stenosis （RAS） in rats. Methods Sixtyfive sprague-dawley （SD） rats were randomly divided into 3 groups, the sham operation group, the operation group, the Panax notoginseng treatment group. The renal artery stenosis （RAS） of the rats were ligated to establish the model of chronic renal ischemia. The rats were killed, respectively, on days 7, 14, 28 and 45 days after operation. HE and Masson staining were applied to explore histological and patho- logical changes in the renal interstitium, α-Smooth muscle actin（α-SMA） was detected by immunohisto- chemistry. The concentrations of IL-2 and PDGF in serum were detected by immunofluorescence assay and ELISA method respectively. Results The degree of renal tubulointerstitial fibrosis, the expression of α-SMA and the serum IL-2 level of PDGF-BB in the operated rats were significantly increased when compared with those in the sham operation group at different time points（P〈0. 01）. The PNS-treated rats had less expression of α-SMA in interstitium, less PDGF-BB level in serum and less degree of renal tu- bulointerstitial fibrosis than those of the operation group（P〈0.01 or P〈0.05）. The serum IL-2 level of the operation group showed a great increase on day 7（P〈0.01） and then decreased to the level of the sham operation group and was significantly lower on day 45 than that of the sham operation group （P〈0.05）. The serum IL-2 level of the PNS-treated group was higher than that of the operation group on day 7 （P〈0.05）, it had no statistical distinction at other times. Conclusion Panax notoginseng saponin may prevent fibrotic process of renal interstitium in chronic renal ischemia rat model by blocking tubular epithelial-myofibroblast transdifferentiation, suppressing serum level of PDGF-BB and inhibiting the increasing of the serum IL-2 level at the early stage.