Effect of triptolide on the regulation of ATP‑binding cassette transporter A1 expression in lipopolysaccharide‑induced acute lung injury of rats.

The aim of this study was to investigate the effect of triptolide on ATP‑binding cassette transporter A1 (ABCA1) expression in lipopolysaccharide (LPS)‑induced acute lung injury (ALI) in rats. Thirty male Sprague Dawley rats weighing 200‑250 g were randomly divided into six groups: Normal (N, n=5), Control (C, n=5), LPS (L, n=5), Triptolide 25 µg (TP1, n=5), Triptolide 50 µg (TP2, n=5) and Triptolide 100 µg (TP3, n=5). The N group was not administered anything; the C group was administered 5 ml/kg normal saline intravenously and 7.5 ml/kg 1% dimethylsulfoxide (DMSO) intraperitoneally; the L group was administered 5 mg/kg 0.1% LPS and 1% DMSO; and the TP1, TP2 and TP3 groups were separately injected with 0.1% LPS and 25, 50 or 100 µg/kg triptolide, respectively. All groups had the same liquid‑injection volume. Arterial blood gases, tumor necrosis factor‑α (TNF‑α) and ABCA1 expression and general pathology were examined following the treatments. It was found that increasing the triptolide dose in the TP1‑3 groups resulted in an increase in the expression of ABCA1 mRNA and protein. As compared with the L group, the ABCA1 expression showed a significant increase in TP2 and TP3 groups (P<0.05). In addition, the expression level of TNF‑α was significantly increased in the L and TP1 groups, as compared with that in the N or C groups (P<0.05). Conversely, a marked decrease in TNF‑α expression was detected in the TP2 and TP3 groups, as compared with the L or TP1 groups (P<0.05). In conclusion, this study found that triptolide could promote the expression of ABCA1 mRNA and protein and inhibit other inflammatory factors during LPS‑induced ALI in rats. Regulating the expression of ABCA1 may be one of the protective mechanisms of triptolide. Furthermore, triptolide‑induced increases in ABCA1 expression occurred in a dose‑dependent manner between 25 and 100 µg/kg.