Synergy Effects Studies Of Rhizoma Belamcandae And Ephedra Sinica Stapf Drug-Couple Compatibility Based On Pharmacokinetics

Shegan Mahuang decoction is a classical TCM prescriptionwith a longhistory for the treatment of bronchial asthma. Its curative effect is safe andreliable and has already confirmed by a large number of clinical andexperimental research. But the internal law of compatibility of this prescriptionhas not been reported yet. In this paper, Shegan-Mahuang, the core drug coupleof Shegan Mahuang Decoction, was regarded as a breakthrough for thepreliminary exploration of the internal mechanism of compatibility of SheganMahuang Decoction.Firstly, we investigated the extraction process of Herba Ephedrae（Mahuang）and Rhizoma Belamcandae（Shegan）. The Orthogonal test L9(33)was employed to optimize the extraction conditions of ephedrine hydrochlorideand pseudoephedrine hydrochloride from Herba Ephedra．The contents ofephedrine and pseudoephedrine were determined by reversed phasehigh-performance liquid chromatography. The optimum extraction conditionwas A1B3C1, that was, adding14times as much50%ethanol containing0.75%hydrochloric acid， extracted twice for0.5hour.While Rhizoma Belamcandae powder （passed through a NO.4sieve）extracted with10-folds75%ethanol for2h, twice, the total flavonoids extraction rate was the highest.Secondly, we evaluated the dosage ratio and anti-asthmatic property.80female Balb/c Mice were divided into8groups randomly: the normal controlgroup, the asthmatic model group, the dexamethasone group, the shegan group,the mahuang group, and threedifferent proportions groups（F1:1、G1:2、H2:1）of drug-couples（n=10in each group）. Asthmatic mouse model was establishedby intraperitoneal injection of ovalbumin. After the treatment was finished, theeosinophil and leucoyte of bronchoalveolar lavage fluid were counted. TheELISA were employed to detected the contents of IL-4、IL-5、IL-13、IFN-γ inPeripheral Blood, and the inflammatory state in lung tissue was evaluated afterhematoxylin-eosin (HE) staining. Results:(1) The levels of eosinophils andleucoyte in BALF were declined in drug-couple group（sP<0.05, vs model group,shegan group and mahuang group）.(2) The levels of IL-4、IL-5、IL-13inPeripheral Blood were reduced while IFN-γ were heightened in drug-pair groups,which showed significant differences compared with Shegan group andMahuang group.(3) Drug-couple group F showed a significant differencecompared to group G and H. Conclusion: Shegan Mahuang drug-couples couldrelieve the asthmatic symptom, decrease airway inflammation and modulate theTh1/Th2imbalance. Particularly, the drug-couple F showed a remarkable effectamong all drug-couple groups.Thirdly, we studied the pharmacokinetics of isoflavonidsin rat plasmaafteroral administration of R. Belamcandae extract or R. Belamcandae and Ephedraextract combination.12SD rats were divided into two groups randomly andadministrated extract from R. Belamcandae or extract from R.belamcandae andEphedra combination orally. The plasma was collected at a series of time points. Then a UHPLC-MS/MS method was established for the determination oftectorigenin, irigenin, and irisflorentin in rat plasma and applied to thepharmacokinetics research in rats.Thet1/2were3.06h for tectorigenin,3.62h foririgenin and3.64h for irisflorentin, the maximum plasma concentration （Cmax）were132.66ng/mL for tectorigenin,288.38ng/mL for irigenin and165.13ng/mL for irisflorentin and the AUC(0t)were1149.88μg/L h fortectorigenin,1158.91μg/L h for irigenin and573.41μg/L h for irisflorentin afteroral administration extract from R. Belamcandae. While thet1/2were3.82h fortectorigenin,3.78h for irigenin and3.93h for irisflorentin, the Cmaxwere131.65ng/mL for tectorigenin,250.8ng/mL for irigenin and144.41ng/mL foririsflorentin, and the AUC(0t)were1410.652μg/L h for tectorigenin,1940.669μg/L h for irigenin and727.701μg/L h for irisflorentin after oral administrationof extract from R. Belamcandae and Ephedra combination, respectively. TheTmaxwere all at0.25h. The results showed that Ephedra had an effect uponpharmacokinetics of isoflavonids from R. Belamcandae in rats.