Pharmacokinetic comparative study of tetramethylpyrazine and ferulic acid and their compatibility with different concentration of gastrodin and gastrodigenin on blood-stasis migraine model by blood-brain microdialysis method.

Tianma pills, a traditional formula made from Ligusticum chuanxiong and Gastrodia elata, are efficacious for the treatment of primary headache. Tetramethylpyrazine (TMP) and Ferulic acid (FA) are the bioactive ingredients of Ligusticum chuanxiong, while Gastrodin and Gastrodigenin are the bioactive ingredients of Gastrodia elata. Pharmacokinetic assessment of TMP, FA, gastrodin or gastrodigenin in blood or brain interstitial fluid (BIF) has been reported in healthy animals. However, the pharmacokinetic properties of TMP and FA have not been studied when they are co-administered in a blood-stasis migraine model. The present research investigated the pharmacokinetic behavior of TMP and FA after oral administration in the presence of different concentrations of gastrodin and gastrodigenin in a blood-stasis migraine model. Pharmacokinetic parameters were determined using blood-brain microdialysis in combination with the UHPLC-MS method. Compared to the control group, in which TMP and FA were administrated without gastrodin or gastrodigenin, the T1/2, MRT, Cmax and AUC0-∞ of TMP and FA were increased. These results indicate that varying concentrations of gastrodin and gastrodigenin play an important role in affecting the pharmacokinetics of TMP and FA. Low concentrations of gastrodin and gastrodigenin (similar to those found in Tianma pills) were more efficacious, validating the utility of the ancient formulation.

[HPLC-UV fingerprints and chemical pattern recognition of Ilicis Pubescentis Radix].

The present study is to establish the fingerprints for the quality evaluation of Ilicis Pubescentis Radix by HPLC-UV. The chromatographic conditions were defined as Phenomenex Luna C18(4.6 mm × 250 mm, 5 µm). Mobile phase was acetonitrile-0.05% phosphoric acid in gradient elution, and the flow rate was 0.8 mL·min⁻¹.Column temperature was 30 °C and the injection volume was 10 µL．The detection wavelength was 210 nm. According to the similarity evaluation, the chemometric method was used to assess the quality of Ilicis Pubescentis Radix. The fingerprints of 16 batches of Ilicis Pubescentis Radix were established. There were 29 common peaks in the fingerprints and 12 common peaks were identified by reference substances. Fingerprints similarity of samples were greater than 0.92. The samples were classified into three groups by hierarchical cluster analysis combined with principal component analysis (PCA) and orthogonal partial least squares-discriminant analysis (OPLS-DA), and seven components were the main markers that cause differences in the different batches of samples. By comparing the on-line UV spectra of chromatographic peaks, the chromatographic fingerprint was divided into three regions: region A showed seventeen main peaks (mainly lignans and phenolic acids); region B showed eight main peaks, which were proved as saponins; region C showed four main peaks, which were proved as other components. The established HPLC-UV fingerprint is highly specific, and can be used to evaluate the quality consistency of different batches of Ilicis Pubescentis Radix.