Hung K Y, Shyu R S, Fang C C, Tsai C C, Lee P H, Tsai T J, Hsieh B S
Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan, Republic of China.
Kidney Int. 2001 Jun;59(6):2316-24. doi: 10.1046/j.1523-1755.2001.00749.x.
Peritoneal fibrosis (PF) is one of the most serious complications after long-term continuous ambulatory peritoneal dialysis (CAPD). Proliferation of human peritoneal mesothelial cells (HPMC) and matrix over-production are regarded as the main processes predisposing to PF. Dipyridamole (DP) has been reported to have potential as an antiproliferative and antifibrotic agent. We thus investigated the effect of DP in inhibiting proliferation and collagen synthesis of HPMC. A rat model of peritonitis-induced PF was also established to demonstrate the in vivo preventive effect of DP.
HPMC was cultured from human omentum by an enzyme digestion
Cell proliferation was measured by the methyltetrazolium assay. Intracellular cAMP was measured using an enzyme immunoassay (EIA) kit. Total collagen synthesis was measured by (3)H-proline incorporation assay. Expression of collagen alpha1 (I) and collagen alpha 1 (III) mRNAs was determined by Northern blotting. The rat model of peritonitis-induced PF was developed by adding dextran microbeads (Cytodex, 8 mg/1 mL volume) to a standardized suspension (3 x 10(9)) of Staphylococcus aureus. DP was administrated via intravenous infusion (4 mg in 1 h) daily for seven days. Macroscopic grading of intraperitoneal adhesions and histological analyses of peritoneal thickness and collagen expression were performed.
Addition of DP to HPMC cultures suppressed serum-stimulated cell proliferation and collagen synthesis. The antimitogenic and antifibrotic effects of DP appear to be predominantly mediated through the cAMP pathway, as DP increased intracellular cAMP in a dose-dependent manner. The macroscopic grade of intraperitoneal adhesion and peritoneal thickness were both significantly increased in animals treated with Cytodex plus S. aureus; on the other hand, DP attenuated these fibrotic changes with statistical significance (P < 0.01). Analysis of gene expression of collagen alpha 1 (I) and alpha1 (III) in the peritoneal tissue of experimental animals yielded similar results.
This study suggests that dipyridamole may have therapeutic potential in treating peritoneal fibrosis.
腹膜纤维化(PF)是长期持续性非卧床腹膜透析(CAPD)后最严重的并发症之一。人腹膜间皮细胞(HPMC)增殖和基质过度产生被认为是导致PF的主要过程。据报道,双嘧达莫(DP)具有抗增殖和抗纤维化的潜力。因此,我们研究了DP对抑制HPMC增殖和胶原蛋白合成的作用。还建立了腹膜炎诱导的PF大鼠模型,以证明DP的体内预防作用。
通过酶消化法从人网膜中培养HPMC。
采用甲基四氮唑法测定细胞增殖。使用酶免疫分析(EIA)试剂盒测定细胞内cAMP。通过³H-脯氨酸掺入法测定总胶原蛋白合成。通过Northern印迹法测定胶原蛋白α1(I)和胶原蛋白α1(III)mRNA的表达。通过向金黄色葡萄球菌的标准化悬液(3×10⁹)中添加葡聚糖微珠(Cytodex,8mg/1mL体积)建立腹膜炎诱导的PF大鼠模型。DP通过静脉输注(1小时内4mg)每日给药7天。对腹膜粘连进行宏观分级,并对腹膜厚度和胶原蛋白表达进行组织学分析。
向HPMC培养物中添加DP可抑制血清刺激的细胞增殖和胶原蛋白合成。DP的抗有丝分裂和抗纤维化作用似乎主要通过cAMP途径介导,因为DP以剂量依赖性方式增加细胞内cAMP。用Cytodex加金黄色葡萄球菌处理的动物腹膜粘连的宏观分级和腹膜厚度均显著增加;另一方面,DP减轻了这些纤维化变化,具有统计学意义(P<0.01)。对实验动物腹膜组织中胶原蛋白α1(I)和α1(III)的基因表达分析得出了类似的结果。
本研究表明双嘧达莫可能具有治疗腹膜纤维化的潜力。