1，25-二羟基维生素D3通过抑制尿激酶型纤溶酶原激活剂受体表达降低足细胞活动力

1,25-Dihydroxyvitamin D_3 reduces motility of podocytes via inhibiting urokinase-type plasminogen activator receptor expression

目的观察1,25-二羟基维生素D_3[1,25(OH)_2D_3]对脂多糖诱导的足细胞活动力和尿激酶型纤溶酶原激活剂受体(uPAR)表达的影响。方法小鼠足细胞分化成熟后分为3组:正常对照组、脂多糖组(50 mg·L^(-1)脂多糖孵育足细胞24 h)、脂多糖+1,25(OH)2D3组[50 mg·L^(-1)脂多糖+1 nmol·L^(-1)的1,25(OH)_2D_3]共同孵育足细胞24 h。采用免疫荧光激光共聚焦、流式细胞术、实时荧光定量PCR、转板迁移测定法等技术,检测足细胞活动力改变以及足细胞uPAR蛋白和uPAR mRNA(Plaur mRNA)的表达。结果转板迁移测定法中每个视野细胞在正常对照组、脂多糖组、脂多糖+1,25(OH)2D3组分别为(8.4±3.8)、(31.3±7.9)、(19.2±6.8)个,脂多糖组膜下层迁移足细胞多于其他2组,脂多糖+1,25(OH)_2D_3组多于正常对照组(P<0.01)。脂多糖组uPAR蛋白荧光信号强于正常对照组,脂多糖+1,25(OH)_2D_3组弱于脂多糖组。脂多糖+1,25(OH)2D3组uPAR蛋白表达率和Plaur mRNA为(31.12±4.46)%和1.97±0.46,均低于脂多糖组[(54.66±8.69)%和3.06±0.93,P<0.05],高于正常对照组[(9.80±3.1 1)%和1.00±0.00,P<0.05]。结论 1,25(OH)_2D_3可能通过抑制uPAR的表达,降低足细胞活动力,起到保护足细胞的作用。

AIM To investigate the effects of 1,25-dihydroxyvitamin D3 （1,25 （OH）2D3） on the lipopolysaccharide （LPS） -induced motility of podocytes and the expression of urokinase-type plasminogen activator receptor （uPAR） in vitro. METHODS Immortalized mouse podocytes were cultured and randomized into three groups ： control group, LPS （50 mg. L-1） group, LPS （50 mg. L-1） ＋ 1,25 （OH） 2D3 （ 1 nmol. L-1） group. The podocytes motility was checked by transwell migration assay. The expression of uPAR in podocytes were detected by immunofluorence method, flow cytometry method and real-time PCR. RESULTS The number of podocytes in the transwell migration assay were 8.4 ± 3.8, 31.3 ± 7.9, 19.2 ± 6.8 in the control group, LPS group and LPS ＋ 1,25 （OH）2D3 group, respectively. The motility of LPS-induced podocytes in the LPS group were increased compared with the other two groups （P 〈 0.01）. The immunofluorescence staining of uPAR protein in the LPS group was increased compared with those in the control group and LPS ＋ 1,25 （OH）2D3 group. The positive expression rate of uPAR protein and the Plaur mRNA in the LPS ＋ 1,25 （OH）2D3 group （（31.12 ± 4.46）% and 1.97 ±0.46） were lower than those in the LPS group （（54.66 ± 8.69）% and 3.06 ± 0.93, P 〈 0.05）, but higher than those in the control group （ （9.80 ± 3.11）% and 1.00 ± 0.00, P 〈 0.05）. CONCLUSION 1,25 （OH）2D3 could reduce LPS-induced motility of podocytes via inhibiting uPAR expression.