Integrating pharmacokinetics and network pharmacology to decipher the efficacy of Fufang Qinlan oral liquid on post infectious cough

Background and aim: Fufang Qinlan oral liquid (QLOL) is a traditional Chinese medicine formula used to treat fevers, sore throats and cough. This study was to evaluate QLOL's therapeutic effects on post infectious cough (PIC) and to investigate Q-markers and action mechanisms by integrating pharmacokinetics and network pharmacology. Materials and methods: PIC rats were measured for cough frequency, organ index, pathological section of lung and inflammatory factors to evaluate the effects of QLOL. Pharmacokinetic analyses were performed using HPLC-QQQ-MS/MS to explore the possible Q-markers of QLOL and the changes of them in vivo. Network pharmacology was used to obtain potential important targets and action mechanisms of treating PIC. The possible hub genes were evaluated using QPCR. Results: The symptoms of cough and lung injury were significantly alleviated and IL-6 and IL-1β were significantly decreased after treatment of QLOL. 6 compounds were considered as possible Q-makers and their pharmacokinetic parameters were analyzed. The compound-target network was constructed to identify 53 important targets. Among them, HSPA8, HSP90AA1, HSP90AB1, YWHAZ, EGFR, ESR1 and EP300 were selected as the core targets because of high degree value and direct connection with inflammation or microbial infection. All 6 compounds had potently binding activity to core targets in molecular docking. The QPCR results showed the up-regulation of core targets expression in QLOL group compared with PIC rats, which validated the effects of QLOL and the accuracy of Q-markers selection. Conclusion: QLOL alleviated PIC symptoms through various targets and mechanisms. The potential Q-markers were baicalein, baicalin, oroxylin A-7-O-glucuronideloside, wogonoside, oroxylin A and forsythoside E. Taxonomy (classification by evise): the experimental approach.