蒺藜总皂甙抑制培养的牛脑微血管内皮细胞表达E选择素

Inhibition of gross saponins from Tribulus terrestris L. on expression of E selectin in cultured bovine cerebral microvessel endothelial cells

目的：观察蒺藜总皂甙（ＧＳＴＴ）对牛脑微血管内皮细胞（ＢＣＭＥＣ）表达Ｅ选择素的影响。方法：流式细胞仪测定白细胞介素１β（ＩＬ－１β）诱导ＢＣＭＥＣ粘附大鼠血单核细胞（ＭＮＣ）和中性粒细胞（ＮＴＰ）的数目；应用ＥＬＩＳＡ法检测ＢＣＭＥＣ表达Ｅ选择素的量。结果：ＢＣＭＥＣ经ＩＬ－１β诱导后，明显增加细胞表面Ｅ选择素的表达；ＢＣＭＥＣ与白细胞的粘附率亦明显增加，对ＭＮＣ的粘附率从（１２．９±０．４）％增至（４５．７±０．６）％，对ＮＴＰ的粘附率从（１４．７±０．３）％增至（４４．９±０．６）％。抗Ｅ选择素单克隆抗体（ＡＥｍＡｂ）能显著降低ＩＬ－１β的诱导作用。在ＩＬ－１β处理前，用ＧＳＴＴ（０．０１～１．００ｇ／Ｌ）与ＢＣＭＥＣ共孵育，则ＧＳＴＴ可浓度依赖性地抑制ＩＬ－１β的诱导作用，降低Ｅ选择素的表达量。

Objective: To study the effect of extract from leaves of gross saponins from Tribulus terrestris L. (GSTT) on expression of E selectin in cultured bovine cerebral microvessel endothelial cells (BCMEC) induced by IL 1β. Methods: IL 1β induced E selectin expression on the cellular surface and endothelial adhesivity toward monocytes (MNC) and neutrophils (NTP) was studied using BCMEC. The adhesive cell number to BCMEC monolayers was counted by flow cytometry. E selectin on the surface was measured by ELISA. Results: Pretreatment of BCMEC with IL 1β significantly enhanced E selectin expression on the cellular surface and increased MNC and NTP adhesion to BCMEC from (12.9±0.4)% to (45.7±0.6)% and from (14.7±0.3)% to (44.9±0.6)%, respectively. Anti E selectin mAb might block the effect of IL 1β. GSTT (0.01～1.00 g/L) inhibited the effect of IL 1β in concentration dependent manner. Conclusion: GSTT inhibited expression of E selectin in BCMEC.