Imatinib-induced hepatotoxicity via oxidative stress and activation of NLRP3 inflammasome: an in vitro and in vivo study.

Imatinib (IM), a milestone drug used in the field of molecular targeted therapy, has been reported to cause serious adverse liver effects, including liver failure and even death. Immune-mediated injury and mitochondrial dysfunction are involved in drug-induced liver injury. However, the mechanism of IM-induced hepatotoxicity remains unclear and warrants further study. In our study, Sprague Dawley rats were administered IM by gavage with 50 mg/kg body weight (BW) once daily for 10 days. Drug-induced liver injury accompanied by inflammatory infiltration was observed in rats following IM exposure, and the expression of NOD-like receptor protein 3 (NLRP3) inflammasome-related proteins was significantly increased compared with that of the control. HepG2 cells were exposed to 0-100 µM IM for 24 h. The results showed that IM decreased cell viability in a dose-dependent manner. Moreover, IM induced a state of obvious oxidative stress and activation of nuclear factor kappa B (NF-κB) in cells, which resulted in the activation of NLRP3 inflammasomes, including caspase 1 cleavage and IL-1ß release. These results were significantly reduced after the use of the antioxidants N-acetyl-l-cysteine or the NF-κB inhibitor pyrrolidine di-thio-carbamate. Furthermore, NLRP3 knockdown significantly reduced the release of inflammatory cytokines and improved cell viability. In summary, our data demonstrated that oxidative stress and NLRP3 inflammasome activation are involved in the process of IM-induced hepatotoxicity. The results of this study provide a reference for the prevention and treatment of IM-induced hepatotoxicity.

Impact of CYP2C19 genotype on voriconazole exposure and effect of voriconazole on the activity of CYP3A in patients with haematological malignancies.

Voriconazole (VRC) is a first-line drug for the treatment of invasive fungal infections (IFIs) and an inhibitor of CYP3A activity. The aims of this study are to investigate the influence of related factors on the plasma concentration of voriconazole and the effect of voriconazole on the activity of CYP3A in patients with haematological malignancies.A total of 89 patients received an initial dose of 6 mg/kg followed by 4 mg/kg every 12 h were included in the study. Blood samples were collected before and 2 h after administration for subsequent testing and for the extraction of DNA samples. Voriconazole and voriconazole N-oxide in the plasma were detected by LC-MS/MS. The effect of voriconazole on CYP3A activity was evaluated by the ratio of the endogenous biomarkers 6ß-hydroxycortisol and cortisol.During the study period, the overall incidence of adverse reactions was 33.6% (with no deaths). The metabolite type of CYP2C19 and combined use of CYP2C19 enzyme inhibitors both had a significant impact on voriconazole exposure. Voriconazole has a long-lasting and potent inhibitory effect on CYP3A activity. The exposure of CYP3A substrate in combination with metabolic enzyme inhibitors voriconazole could increase. Therefore, the combination uses with voriconazole need to be considered carefully and assessed adequately.

Strophalloside induces apoptosis of SGC-7901 cells through the mitochondrion-dependent caspase-3 pathway.

Cardenolides with special chemical structures have been considered as effective anti-cancer drugs in clinic trials. Strophalloside is a cardenolide we recently isolated from Antiaris toxicaria obtained from Hainan, China. The aim of this study was to investigate the possible anticancer effects induced by strophalloside and the underlying molecular mechanism. Gastric carcinoma SGC-7901 cells were treated with strophalloside at various concentrations for different times, and resulting cell viability was determined by the MTT assay, and the motility and invasion of tumor cells were assessed by the Transwell chamber assay. Apoptosis were measured by Annexin V-FITC/PI and Hoechst staining. The changes of mitochondrial transmembrane potential were examined by a JC-1 kit. The expressions of pro-apoptotic protein cytochrome c, caspase-3 and caspase-9 were detected by western blotting analysis. The results showed that strophalloside was capable of reducing cell viability, inhibiting cell growth, and suppressing cell migration and invasion in a time- and dose-dependent manner. Mitochondrial membrane potential declined and the concentration of cytochrome c increased in cytoplasm and caspase-3 and caspase-9 were cleaved into activated states, suggesting that cytochrome c was released from the mitochondrion to cytoplasm and finally activated the caspase-dependent apoptosis pathway. Our results indicate that strophalloside is a potential anticancer drug.

Simultaneous Determination of Cortisol and 6ß-Hydroxycortisol in Human Plasma by Liquid Chromatography-Tandem Mass Spectrometry.

The feasibility of taking the ratio of 6ß-hydroxycortisol (6ß-OHCOR) to cortisol (COR) in plasma as a biomarker to reflect CYP3A4 activity needs to be verified, but the low concentration of 6ß-OHCOR which is an endogenous substance in plasma presents a challenge for determination. In this study, a Liquid chromatography with tandem mass spectrometry (LC-MS/MS) method was established to simultaneously quantify the COR and 6ß-OHCOR in plasma with COR-d4 and 6ß-OHCOR-d4 as internal standards (ISs). Plasma samples were treated by protein precipitation using acetonitrile. Separation with a gradient elution within 5 min was achieved on C18+ column utilizing 5 mM ammonium formate and methanol. An API 4,000 MS in multiple reaction monitoring mode with transitions of 407.1 â†’ 361.1 and 423.1 â†’ 347.1 was utilized. Albumin solution was used as a surrogate matrix, with good linearities over the concentration of 1.20-300 ng/mL for COR and 0.0400-10.0 ng/mL for 6ß-OHCOR. The precisions for intrarun and interrun were < 6.8%, and the accuracy was fell in the interval of -5.2 to 3.5%. Matrix effect was not found. Recovery was close to 100.0%. Stability was confirmed under the storage and processing conditions. The validated method was applied to evaluate the inhibitory effect of voriconazole to CYP3A by the ratio of 6ß-OHCOR to COR.

Effects of ABCB1, UGT1A1, and UGT1A9 Genetic Polymorphisms on the Pharmacokinetics of Sitafloxacin Granules in Healthy Subjects.

Sitafloxacin, a new fluoroquinolone, has strong antibacterial activity. We evaluated the effects of sitafloxacin granules in single-dose and multidose cohorts and the effects of ABCB1, UGT1A1, and UGT1A9 genetic polymorphisms on the pharmacokinetics (PK) of sitafloxacin in healthy subjects. The single-dose study included 3 fasted cohorts receiving 50, 100, and 200 mg of sitafloxacin granules and 1 cohort receiving 50 mg of sitafloxacin granules with a high-fat meal. The multidose study included 1 cohort receiving 100 mg of sitafloxacin granules once daily for 5 days. PK parameters were calculated using noncompartmental parameters based on concentration-time data. The genotypes for ABCB1, UGT1A1, and UGT1A9 single-nucleotide polymorphisms were determined using Sanger sequencing. Subsequently, the association between sitafloxacin PK parameters and target single-nucleotide polymorphisms was analyzed. Sitafloxacin granules were well tolerated up to 200 and 100 mg in the single-dose and multidose studies, respectively. Sitafloxacin AUC and Cmax increased linearly within the detection range, and a steady state was reached within 3 days after the administration of multiple oral doses. Our findings showed that Cmax was lower in the ABCB1 (rs1045642) mutation group, whereas t1/2 was longer in the UGT1A1 (rs2741049) and UGT1A9 (rs3832043) mutation groups. In conclusion, sitafloxacin granules were safe at single doses and multiple doses up to 200 and 100 mg/day, respectively, with a linear plasma PK profile. However, ABCB1 (rs1045642), UGT1A1 (rs2741049), and UGT1A9 (rs3832043) genetic polymorphisms are likely to influence the Cmax or t1/2 and thereby merit further clinical evaluation.

Microencapsulation of tumor lysates and live cell engineering with MIP-3α as an effective vaccine.

The combination of several potential strategies so as to develop new tumor vaccines is an attractive field of translational medicine. Pulsing tumor lysates with dendritic cells (DCs), in-vivo attraction of DCs by macrophage inflammatory protein 3α (MIP-3α), and reversion of the tumor suppressive microenvironment have been tested as strategies to develop tumor vaccines. In this study, we generated an alginate microsphere (named PaLtTcAdMIP3α) that encapsulated tumor lysates, live tumor cells engineering with a recombinant MIP-3α adenovirus and BCG. We used PaLtTcAdMIP3α as a model vaccine to test its antitumor activities. Our results showed that PaLtTcAdMIP3α expressed and excreted MIP-3α, which effectively attracted DCs ex vivo and in vivo. Injection of PaLtTcAdMIP3α into tumor-bearing mice effectively induced both therapeutic and prophylactic antitumor immunities in CT26, Meth A, B16-F10 and H22 models, but without any ensuing increase in adverse effects. Both tumor-specific cellular and humoral immune responses, especially the CD8(+) T cell-dependent cytotoxic T immunity, were found in the mice injected with PaLtTcAdMIP3α. The anti-tumor activity was abrogated completely by depletion of CD8(+) and partially by CD4(+) T lymphocytes. In addition, the number of IFN-γ-producing CD8(+) T cells in spleen and tumor tissues was significantly increased; but the number of CD4(+)CD25(+)FOXP3(+) regulatory T cells (Treg) in tumor tissues was decreased. These data strongly suggest that a combination of multi-current-using strategies such as the novel approach of using our PaLtTcAdMIP3α microspheres could be an effective tumor model vaccine.