Celastrol and triptolide, as the two main bio-activity ingredients in Tripterygium wilfordii, have wide anticancer pharmacological potency, as well as anti-inflammatory and immunosuppression effects. However, they have potential hepatotoxicity and underlying mechanisms of them-induced toxicity mediated by hepatic CYP450s have not been well delineated. In the present study, we accessed the toxic effects and possible mechanism of celastrol and triptolide on primary rat hepatocytes. Models of subdued/enhanced activity of CYP450 enzymes in primary rat hepatocytes were also constructed to evaluate the relationship between the two ingredients and CYP450s. LC-MS/MS was used to establish a detection method of the amount of triptolide in rat hepatocytes. As the results, cell viability, biochemical index, and mitochondrial membrane potential indicated that celastrol and triptolide had toxic potencies on hepatocytes. Moreover, the toxic effects were enhanced when the compounds combined with 1-aminobenzotriazole (enzyme inhibitor) while they were mitigated when combined with phenobarbital (an enzyme inducer). Meanwhile, celastrol could affect the amount of triptolide in the cell. We therefore put forward that increase of triptolide in the cell might be one of the main causes of hepatotoxicity caused by Tripterygium wilfordii.

Background and Objective: Traditional Chinese medicines that have inhibitory effects on the CYP3A4 enzymes were screened and their inhibitory effects were verified with in vitro bioassay. Methods: The computer virtual screening methods, including the CYP3A4 enzyme pharmacophore model and the molecular docking method were used to rapidly screen the potential CYP3A4 inhibitors in Traditional Chinese Medicine Database (TCMD), and then in vitro experiments were conducted to validate the computational data. Results: A total of 413 chemical components in TCMD that have potential inhibitory effects on the CYP3A4 enzyme were screened, and four kinds of traditional Chinese medicines (Abrus precatorius, Andrographis paniculata, Angelica pubescens f.biserrata and Lithospermum erythrorhizon) contained the most potential CYP3A4 inhibitors; The results of the in vitro experiments showed that these four traditional Chinese medicine extracts all had certain degrees of inhibition on the CYP3A4 enzyme, with IC50 values of 5.15, 14.97, 15.2, and 24.21 μg/ml, respectively. Conclusion: The extracts of Abrus precatorius, Andrographis paniculata, Angelica pubescens f. biserrata and Lithospermum erythrorhizon had certain inhibitory effects on the CYP3A4 enzyme, and attention should be paid to the possible adverse reactions when they were used in combination with the CYP3A4 enzyme-substrate drugs. A combination of computational approaches might be a useful tool to identify potential inhibitors of the CYP3A4 enzyme from traditional Chinese medicine.

Background/Objectives: Pseudomonas aeruginosa is a notorious multidrug-resistant pathogen that causes serious acute and chronic infections by employing quorum sensing (QS)-regulated virulence, biofilm formation, and host-damaging inflammation. To overcome the yield limitation of two previously identified marine secondary metabolites with dual QS inhibitory and PPAR-γ agonistic activities, we further screened marine-derived natural products for more abundant candidates with similar anti-virulence and anti-inflammatory properties. Methods: In this study, isoflavones were evaluated for anti-QS and PPAR-γ transactivation activities using reporter gene assays, and for antibacterial, anti-virulence, and anti-inflammatory effects via broth microdilution, biofilm, G. mellonella infection, and ELISA cytokine assays. Results: Daidzein and genistein were selected for their optimal anti-QS and PPAR-γ activation activities. They inhibited a key QS regulator and suppressed pyocyanin production and biofilm formation in P. aeruginosa without affecting bacterial growth, indicating minimal selective pressure for resistance. In addition, daidzein and genistein were found to synergistically sensitize the wild-type P. aeruginosa strain to gentamicin, carbenicillin, tobramycin, ampicillin, and polymyxin B, and synergistically or partially synergistically sensitize a multidrug-resistant strain to gentamicin, tobramycin, and ampicillin. Moreover, a Galleria mellonella infection model confirmed that daidzein and genistein significantly enhance the efficacy of gentamicin against P. aeruginosa infection in vivo. Furthermore, in host macrophages, daidzein and genistein significantly inhibited LPS-induced production of NO, IL-6, and IL-1β when combined with an RXR agonist, implying a protective effect on host tissues through PPAR-γ activation. Conclusions: These findings demonstrate that daidzein and genistein serve as effective adjuncts to conventional antibiotics, exerting multifaceted actions against P. aeruginosa infection.