Study on the pharmacokinetics and brain tissue distribution of eight anti-inflammatory active components in normal and neuroinflammatory rats orally administered with extract of Tinospora sinensis (Lour.) Merr. using the UPLC-MS/MS method.

Tinospora sinensis (Lour.) Merr. (Tinospora sinensis) is a traditional Chinese medicine commonly used by Tibetan people in China to prevent and treat diseases such as senile dementia, neuroinflammatory, and rheumatoid arthritis. However, the pharmacokinetic characteristics and tissue distribution of Tinospora sinensis active components in vivo, especially the distribution of brain regions, are unclear. Herein, a stable and accurate ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed and validated to compare the pharmacokinetic patterns and differences in brain tissue distribution of eight anti-inflammatory active components in normal and neuroinflammatory rats after oral administration of extracts from Tinospora sinensis. ACE Excel 3 C18-AR (100 × 2.1 mm, 1.7 μm) column was used for gradient elution with 0.1 % formic acid water (A) and acetonitrile (B), rifampicin as an internal standard, electrospray ionization (ESI) positive and negative ion mode scanning, multiple reaction monitoring (MRM) determination, and DAS 2.0 software analysis. The UPLC-MS/MS method established through verification is accurate and reliable, and the methodology can meet the quantitative requirements. The pharmacokinetic results showed differences in the pharmacokinetic process and brain tissue distribution between normal rats and rats with neuroinflammation. All eight anti-inflammatory active components can be rapidly absorbed into the bloodstream (Tmax ≤ 2 h), but the plasma metabolism rate of rats with neuroinflammation is faster and the brain content is lower. Neuroinflammation has a significant impact on the in vivo process of oral administration of Tinospora sinensis in rats. The study provides experimental evidence for the quality control and clinical application of Tinospora sinensis.