Effect Of T20, An Compound Of Anthraquinone,on The P-gp Function And Expression In The RBMECs Under Ischemic Injury

Objective: To investigate the anthraquinone compound T20 effects on the P-gp function and expression under ischemia injuryed in rBMECs.Methods: 1. Cultured the rBMECs and astrocytes by primary culture, and the MTT assay was used to measure the cell survival rate. Prepare the rBMECs and astrocytes construct BBB models in vitro with transwell. After treatment with T20 in rBMECs, the Papp of Rh123 were measured to evaluate paracellular transport reflecting the function of P-gp and the Papp of Na F were measured to evaluate the tight junctions of BBB models. The levels of P-gp were determined by Western blot. 2. The cytotoxicity toward rBMEC was induced by different concentration of Na₂S₂O₄. The MTT assay was used to measure the astrocytes treatmented by different concentration of Na₂S₂O₄ survival rate at the time of 6h. After treatment with Na₂S₂O₄ in astrocytes, the Papp of Rh123 were measured to evaluate paracellular transport reflecting the function of P-gp and the Papp of Na F were measured to evaluate the tight junctions of BBB models. Western Blot was used to detecte the protein expression of P-gp and TNF-?. 3. The astrocytes treatmented by different concentration of Aspirin and the rBMECs treatmented by different concentration of PD, PDTC and ZnPP used the MTT assay to measure. After treatment with T20 in astrocytes or PD,PDTC and ZnPP in rBMECs, the Papp of Rh123 were measured to evaluate paracellular transport reflecting the function of P-gp and the Papp of Na F were measured to evaluate the tight junctions of BBB models. The protein expression of P-gp, p-ERK, NF-?B and HO-1 were detected by Western blot.Results: 1. The anthraquinone compound T20 dose-dependently reduced the P-gp function and expression in normal cultured rBMECs. 2. The astrocytes was induced by 3.75 m M Na₂S₂O₄, which can improve the function and expression of P-gp. In ischemia injuryed rBMECs, the anthraquinone compound T20 reduced the P-gp function and expression in a concentration-dependent manner. 3. The anthraquinone compound T20 decreased the level of TNF-? in astrocytes, and then inhibited the activation of p-ERK1/2and p-I?B-?, reduced HO-1, resulted in the change of P-gp function and expression in ischemia injuryed rBMECs.Conclusions: The anthraquinone compound T20 dose-dependently reduced the P-gp function and expression in ischemia injuryed rBMECs, through decreased the level of TNF-? in astrocytes underischemic injury, and then inhibited the activation of MAPK/ERK and NF-?B, reduced HO-1, resulted in the change of P-gp function and expression in rBMECs.