ABSTRACT
Objective:To study the nephrotoxicity induced by triptolide ( TP) on MDCK cell model and investigate its effect on oxidative stress. Methods:Aristolochic acid was chosen as the positive control. After the MDCK cells were incubated with 0. 5, 5, 50 and 500 nmol·L-1 TP for 24h, MTT method was used to observe the cell inhibiting rate and lactate dehydrogenase (LDH) release test was used to detect the cell membrane damage caused by TP. The cell morphology was observed under an inverted microscope. After the MDCK cells were incubated with 500 nmol·L-1 TP respectively for 30min, 1h, 2h, 4h and 6h, the level of reactive oxygen species ( ROS) was detected using 2′,7′-dichlorodihydro-fluorescein diacetate ( DCFH-DA) as the fluorescent probe. Results:Compared with those of the negative control group, the cell inhibiting rates and the relative LDH release rates in TP-treated group were increased sig-nificantly(P<0. 01). The cells in TP-treated group were creased, turned into the round shape and began to shed off. After the MDCK cells were incubated with TP for 30min, the level of ROS reached the highest value, and then began to decrease (P<0. 01). Conclu-sion:TP can induce the toxic effects on MDCK cells and the mechanism may be related to oxidative stress.
ABSTRACT
OBJECTIVE:To establish a method for detecting bacterial endotoxins in methylthioninium chloride injection (MCI) quantitatively. METHODS: Kinetic turbidimetric limulus test was applied to detect bacterial endotoxins in MCI quantitatively, and compared with gel-clot method. RESULTS: MCI was un-interfered with the test for bacterial endotoxins at the concentration of 0.125 mg?mL-1; the content of bacterial endotoxins in all samples tested (10 mg?mL-1) were not more than 0.25 EU?mg -1, which were in accordance with the result of gel-clot method. CONCLUSIONS: Kinetic turbidimetric limulus test provides a new way to detect bacterial endotoxins in MCI quantitatively.