Efficacy and Safety of Toutongning Capsule in Patients with Migraine: A Multicenter, Randomized, Double-Blind, Placebo-Controlled Trial.

Objective: Toutongning (TTN) capsule, a Chinese patent medicine, is used as a prophylactic treatment for migraine. The present study was conducted as a postmarketing evaluation of the efficacy and safety of TTN capsule. Design: A randomized, double-blind, placebo-controlled trial. Location: Patients recruited from 14 medical centers in China from May 2014 to August 2015. Subjects: Patients between 18 and 65 years of age with a diagnosis of migraine. Interventions: The patients were randomly assigned to receive either TTN (1200 mg, three times daily) or a matched placebo (1:1) for 4 weeks. Outcome measures: The primary outcome measured was a minimum 50% reduction in the frequency of headaches from the 4-week baseline period to the last 4 weeks of the 12-week trial. Secondary outcomes included duration, days, and visual analog score of headache attack, interval between headache attacks, usage of acute analgesics, and score on the Headache Impact Test-6. In addition, all patients were evaluated for adverse events (AEs). Results: This study initially enrolled 400 patients; a total of 378 participants completed the experiment while fulfilling all study requirements. TTN had a superior effect compared with the placebo on both the primary and secondary outcome measures without any serious AEs or unexpected side effects. Conclusion: TTN can effectively prevent the occurrence of migraine headaches and is well-tolerated and safe. TTN may exhibit a persistent therapeutic effect even after cessation of use. Trial Registration number: ChiCTR-IPR-15007058.

[The pharmacological mechanism of gastrodin on calcitonin gene-related peptide of cultured rat trigeminal ganglion].

The Chinese herbal medicine Tianma (Gastrodia elata) has been used for treating and preventing primary headache over thousands of years, but the exact pharmacological mechanism of the main bioactive ingredient gastrodin remains unclear. In present study, the effects of gastrodin on calcitonin gene-related peptide (CGRP) and phosphorylated extracellular signal-regulated kinase1/2 (pERK1/2) expression were observed in rat trigeminal ganglion (TG) after in vitro organ culture to explore the underlying intracellular mechanism of gastrodin on primary vascular-associated headache. CGRP-immunoreactivity (CGRP-ir) positive neurons count, positive area, mean optical density and integrated optical density by means of immunohistochemistry stain were compared at different concentrations of gastrodin, which was separately co-incubated with DMEM in SD rat TG for 24 hours. Only at 5 or 10 mmol L(-1) concentration, gastrodin demonstrated significantly concentration-dependent reduction of CGRP-ir (+) expression and its action closed to 1.2 mmol L(-1) sumatriptan succinate. While at 2.5, 20, and 40 mmol L(-1) concentration, gastrodin did not show remarkable effects on CGRP-ir (+) expression. The optimal concentration of gastrodin (5 and 10 mmol L(-1)) similarly inhibited CGRP-mRNA expression level separately compared with 1.2 mmol L(-1) sumatriptan succinate and 10 micromol L(-1) flunarizine hydrochloride, which was quantitatively analyzed by real-time PCR (RT-PCR). pERK1/2 level was examined by Western blotting after co-cultured with optimal concentration of gastrodin and effective specific ERK1/2 pathway inhibitors PD98059, U0126. The result indicated that gastrodin significantly reduced pERK1/2 protein actions similarly to ERK1/2 pathway specific blockade. It suggests ERK1/2 signaling transduction pathway may be involved in gastrodin intracellular mechanism. This study indicates gastrodin (5 and 10 mmol L(-1)) can remarkably reduce CGRP-ir (+) neuron, CGRP-mRNA and pERK1/2 expression level in cultured rat TG, with its actions similar to the effective concentration of sumatriptan succinate, flunarizine hydrochloride and specific ERK1/2 pathway blocker. The intracellular signaling transduction ERK1/2 pathway may be involved in the gastrodin reducing CGRP up-regulation in rat TG after organ culture.