Gordon J A, Warnock L J, Spector A A
Department of Internal Medicine, University of Iowa College of Medicine, Iowa City 52242.
J Clin Invest. 1993 Jul;92(1):169-78. doi: 10.1172/JCI116545.
Peroxisomal-deficient skin fibroblasts from patients with Zellweger's syndrome or infantile Refsum's disease produced fewer prostaglandins than normal skin fibroblasts. Radioimmunoassay indicated a 45-55% decrease in prostaglandin E2 (PGE2) production when Zellweger's fibroblasts were incubated with arachidonic acid. This deficiency was not overcome by pretreatment of the Zellweger's fibroblasts with media containing arachidonic acid, and it was not due to channeling of arachidonic acid into other eicosanoid products. Modifications in the peroxide tone of the Zellweger's fibroblasts by addition of H2O2 or catalase failed to increase PGE2 production. Using Northern analysis, we were unable to detect an mRNA transcript for PGH synthase in unstimulated Zellweger fibroblasts but identified a 4.2-kb mRNA transcript after treatment with phorbol myristate acetate (PMA). Treatment for 6 h with 10 nM PMA raised PGE2 production in normal and Zellweger fibroblasts to equivalent levels. These increases were prevented by addition of H-7, staurosporine, cycloheximide, or actinomycin D. Our findings suggest that the reduced PGE2 production in peroxisomal deficient fibroblasts is due to a decrease in PGH synthase mRNA. The reduction in PGH synthase can be overcome by treatment of the cells with agents which enhance gene expression.
患有泽尔韦格综合征或婴儿型雷夫叙姆病患者的过氧化物酶体缺陷皮肤成纤维细胞产生的前列腺素比正常皮肤成纤维细胞少。放射免疫分析表明，当将泽尔韦格综合征患者的成纤维细胞与花生四烯酸一起孵育时，前列腺素E2（PGE2）的产生减少了45%-55%。用含有花生四烯酸的培养基预处理泽尔韦格综合征患者的成纤维细胞并不能克服这种缺陷，而且这不是由于花生四烯酸被分流到其他类二十烷酸产物中所致。通过添加过氧化氢或过氧化氢酶来改变泽尔韦格综合征患者成纤维细胞的过氧化物状态并不能增加PGE2的产生。使用Northern分析，我们在未受刺激的泽尔韦格综合征患者成纤维细胞中未能检测到PGH合酶的mRNA转录本，但在用佛波酯肉豆蔻酸酯（PMA）处理后鉴定出了一个4.2 kb的mRNA转录本。用10 nM PMA处理6小时可使正常和泽尔韦格综合征患者的成纤维细胞中的PGE2产生增加到同等水平。添加H-7、星形孢菌素、环己酰亚胺或放线菌素D可阻止这些增加。我们的研究结果表明，过氧化物酶体缺陷的成纤维细胞中PGE2产生减少是由于PGH合酶mRNA减少所致。用增强基因表达的试剂处理细胞可以克服PGH合酶的减少。
