Development and full validation of an LC-MS/MS methodology to quantify capmatinib (INC280) following intragastric administration to rats.

A highly sensitive, specific and simple LC-MS/MS method for quantification of capmatinib (INC280) in rat plasma was presented. The LC-MS/MS method was validated in terms of specificity and selectivity, linearity, accuracy and precision, matrix effect, extraction recovery, dilution integrity, carryover and stability as per the US Food and Drug Administration's bioanalytical method validation guideline. The validated assay was applied for quantification of capmatinib from a pharmacokinetic study in rats following oral administration at the doses of 1.0, 3.0 and 9.0 mg/kg. The calibration curve ranges from 1 to 2000 ng/ml with desirable linearity and r2 > 0.99. The intra- and inter-batch accuracies were within 99.24-103.59 and 97.76-102.83% with coefficients of variation 5.08-7.36 and 3.18-4.99%, respectively. No significant interference was observed by endogenous peak at the retention time of capmatinib and IS. The assay was free from any matrix effect and showed precise recovery across the calibration curve range, and samples were stable under all experimental conditions. The validated assay was successfully applied to analyze plasma samples of pharmacokinetic study in rat to determine the concentration of capmatinib. In summary, a novel method for analyzing capmatinib in rat plasma has been successfully validated and is now being utilized for quantification of capmatinib from pre-clinical studies.

Dexmedetomidine suppressed the biological behavior of RAW264.7 cells treated with LPS by down-regulating HOTAIR.

Background: Previous studies have revealed dexmedetomidine have potential protective effects on vital organs by inhibiting the release of inflammatory cytokines. To investigate the effects of dexmedetomidine on sepsis, especially in the initial inflammatory stage of sepsis. RAW264.7 cells were used as the cell model in this study to elucidate the underlying mechanisms. Methods: In this study, we conducted several assays to investigate the mechanisms of dexmedetomidine and HOTAIR in sepsis. Cell viability was assessed using the CCK-8 kit, while inflammation responses were measured using ELISA for IL-1ß, IL-6, and TNF-α. Additionally, we employed qPCR, MeRIP, and RIP to further explore the underlying mechanisms. Results: Our findings indicate that dexmedetomidine treatment enhanced cell viability and reduced the production of inflammatory cytokines in LPS-treated RAW264.7 cells. Furthermore, we observed that the expression of HOTAIR was increased in LPS-treated RAW264.7 cells, which was then decreased upon dexmedetomidine pre-treatment. Further investigation demonstrated that HOTAIR could counteract the beneficial effects of dexmedetomidine on cell viability and cytokine production. Interestingly, we discovered that YTHDF1 targeted HOTAIR and was upregulated in LPS-treated RAW264.7 cells, but reduced in dexmedetomidine treatment. We also found that YTHDF1 increased HOTAIR and HOTAIR m6A levels. Conclusions: Collectively, our results suggest that dexmedetomidine downregulates HOTAIR and YTHDF1 expression, which in turn inhibits the biological behavior of LPS-treated RAW264.7 cells. This finding has potential implications for the prevention and treatment of sepsis-induced kidney injury.