CULTURED HUMAN SYNOVIAL FIBROBLASTS RAPIDLY METABOLIZE KININS AND NEUROPEPTIDES
CULTURED HUMAN SYNOVIAL FIBROBLASTS RAPIDLY METABOLIZE KININS AND NEUROPEPTIDES
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DOI：
10.1172/jci115975
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发表时间：
1992-09-01
影响因子：
15.9
通讯作者：
WARD, PE
中科院分区：
文献类型：
--
作者：
BATHON, JM;PROUD, D;WARD, PE
激肽和P物质由于其诱导血管舒张、水肿和疼痛的能力而与炎性关节炎的发病机制有关。这些肽在体内的相对生物学效力将至少部分取决于它们在关节中的卡替林速率。我们假设人类滑膜衬里细胞可能通过细胞表面相关肽酶的降解来调节关节内激肽和神经肽的水平。我们将完整的人滑膜成纤维细胞暴露于激肽和P物质，在存在或不存在特异性肽酶抑制剂的情况下，并测量剩余的完整底物和随时间产生的降解产物的量。在滑膜细胞的细胞表面上鉴定了氨肽酶M（AmM; EC 3.4.11.2）、中性内肽酶-24.11（NEP-24.11; EC 3.4.24.11）和二肽基（氨基）肽酶IV（DAP IV; EC 3.4.14.5）。缓激肽降解完全是由于NEP-24.11（1.39+/-0.29 nmol/min/孔）。赖氨酰缓激肽也被NEP-24.11降解（0.80+/-0.19 nmol/min/孔）;然而，在存在磷酰胺的情况下，可以证明AmM介导的向缓激肽的转化（3.74+/-0.46 nmol/min/孔）。NEP-24.11的联合作用（0.93+/-0.15 nmol/min/孔）和DAP IV（0.84+/-0.18 nmol/min/孔）负责物质P的降解。（2.44+/-0.33 nmol/min/孔）和NEP-24.11（1.30+/-0.45 nmol/min/孔）负责阿片肽[Leu 5]脑啡肽的降解。通过合成底物水解、抑制谱和免疫学鉴定确认了三种肽酶中每一种的身份。在类风湿关节炎和骨关节炎关节来源的细胞中鉴定的肽酶谱是相同的。这些数据表明人滑膜成纤维细胞是三种特异性肽酶的丰富来源，并表明它可能在调节关节中的肽水平方面发挥重要作用。
Kinins and substance P have been implicated in the pathogenesis sis of inflammatory arthritis by virtue of their abilities to induce vasodilation, edema, and pain. The relative biological potencies of these peptides in vivo would depend at least in part upon their rates of catabolism in the joint. We hypothesized that human synovial lining cells may regulate intraarticular levels of kinins and neuropeptides via degradation by cell surface-associated peptidases. We exposed intact human synovial fibroblasts to kinins and substance P, in the presence or absence of specific peptidase inhibitors, and measured the amount of intact substrate remaining and degradation product(s) generated over time. Aminopeptidase M (AmM; EC 3.4.11.2), neutral endopeptidase-24.11 (NEP-24.11; EC 3.4.24.11), and dipeptidyl(amino)peptidase IV (DAP IV; EC 3.4.14.5) were identified on the cell surface of synovial cells. Bradykinin degradation was due entirely to NEP-24.11 (1.39+/-0.29 nmol/min per well). Lysylbradykinin was also degraded by NEP-24.11 (0.80+/-0.19 nmol/min per well); however, in the presence of phosphoramidon, AmM-mediated conversion to bradykinin (3.74+/-0.46 nmol/min per well) could be demonstrated. The combined actions of NEP-24.11 (0.93+/-0.15 nmol/min per well) and DAP IV (0.84+/-0.18 nmol/min per well) were responsible for the degradation of substance P. AmM (2.44+/-0.33 nmol/min per well) and NEP-24.11 (1.30+/-0.45 nmol/min per well) were responsible for the degradation of the opioid peptide, [Leu5]enkephalin. The identity of each of the three peptidases was confirmed via synthetic substrate hydrolysis, inhibition profile, and immunological identification. The profiles of peptidase enzymes identified in cells derived from rheumatoid and osteoarthritic joints were identical. These data demonstrate the human synovial fibroblast to be a rich source of three specific peptidases and suggest that it may play a prominent role in regulating peptide levels in the joint.