[Induction of expression of von Willebrand factor cleaving protease of rat aortic endothelial cell by lipopolysaccharide challenge].

OBJECTIVE: To investigate the dose response effect and time response effect of lipopolysaccharide(LPS) on von Willebrand factor cleaving protease (ADAMTS-13, Vwf-cp) mRNA expression and protein in rat aortic endothelial cells (RAECs). METHODS: RAECs were grown by culturing of aortic tissue. When ARECs were cultured for one week, it was co-cultured by 1:3 to reach 4-5 generations. ARECs were randomly divided into five groups: control group and four LPS stimulation groups (0.01, 0.1, 1 and 5 µg/ml) . The RAECs and supernatants were obtained at 12, 24, 48, and 72 hours after being stimulated by LPS. ADAMTS-13 mRNA expression of RAECs was assessed by quantitation reverse transcription-polymerase chain reaction (RT-PCR), and protein of ADAMTS-13 in supernatants was determined by enzyme linked immunoadsorbent assay (ELISA). RESULTS: In the control group RAECs were shown to express ADAMTS-13 at both protein and mRNA levels. With the increase of concentration of LPS, or increase in stimulus duration, expression of ADAMTS-13 mRNA and protein were gradually lowered. Compared with the control group (25.22 ±1.41), the level of ADAMTS-13 mRNA in 0.01 µg/ml LPS stimulation group was markedly decreased at 48 hours (18.78±0.86, P<0.01). At 24 hours, the levels of ADAMTS-13 mRNA (23.43±0.63, 22.41±0.76) were markedly decreased in 0.1 µg/ml and 1 µg/ml LPS stimulation groups (P<0.05 and P<0.01). The level of ADAMTS-13 mRNA (20.01±2.47) in 5 µg/ml LPS stimulation group was markedly decreased at 12 hours (P<0.01). Compared with the control group [(115.76±2.36) ng/ml], protein level of ADAMTS-13 [(113.43±1.07) ng/ml] was markedly decreased at 12 hours in 0.01 µg/ml LPS stimulation group (P<0.05). The protein level of ADAMTS-13 [(7.63±2.64) ng/ml] was lowest in 5 µg/ml LPS stimulation group at 72 hours (P<0.01). CONCLUSION: Normal RAECs can express ADAMTS-13 at both mRNA and protein to certain extent. The expression of ADAMTS-13 mRNA and protein are decreased after LPS challenge in different concentrations for different duration in dose dependent and time dependent manner.