Multi-compound Pharmacokinetic Investigation Of LianhuaQingwen Capsule:Systemic Exposure To And Disposition And Adrenergic Agonist Activities Of Compounds Originating From Honey-fried Ephedra Sinica Herbaceous Stem(Zhi-Mahuang)

Objective:Lianhua Qingwen capsule is a Chinese herbal medicine recommended in the official guideline for the diagnosis and treatment of SARS-Co V-2.It is mainly used to treat patients during medical observation period,mild and moderate illness.The capsule is prepared from a combination,comprising 12 herb medicine and 1 mineral.Honey-fried Ephedra sinica Stapf herbaceous stem（Zhi-Mahuang）is one of the traditional Chinese medicines composed of Lianhua Qingwen capsule.Mahuang has the effect of diaphoresis,anti-asthma and diuretic.Zhi-Mahuang has the effect of moistening lung to arrest cough.When taking Mahuang extract over recommended dose,it can cause adverse effects such as hypertension,heart failure and sudden death.The chemical composition,efficacy and adverse effects of the compounds of Mahuang and Mahuang-containing preparations are unclear due to their complex composition.The association of the pharmacokinetics and pharmacodynamics of Mahuang or Mahuang-containing preparations has not been systematically studied.Therefore,the aim of this investigation was to reveal the significant exposure compounds,their disposition and efficacy originating from Zhi-Mahuang after dosing Lianhua Qingwen capsule.It has great significance to clarify the compounds,concentrations and mechanisms of Mahuang for the safe use of Mahuang ingredients and Mahuang-containing extract preparations.Methods:Based on the analysis of chemical composition and quality consistency of Zhi-Mahuang in Lianhua Qingwen,the pharmacokinetics were studied in vivo and in vitro between human and rats.All samples were analyzed by LC-MS/MS or UPLC/TOF-MS.Based on the chemical composition,systemic exposure compounds and various in vivo and in vitro studies,this study reveal the potential therapeutical and adverse effect compounds and their adrenergic agonist activities.Results:A total of 39 constituents,originating from the component Zhi-Mahuang,were detected and characterized in samples of Lianhua Qingwen.Ephedrine（1;label daily dose:5.8μmol/day）and pseudoephedrine（2;2.8μmol/day）were the major phenylalkylamine compounds of Zhi-Mahuang and they belong to biopharmaceutics classification system class I.Ephedrine and pseudoephedrine were the main systemic exposure compounds in volunteers after receiving Lianhua Qingwen.The C_max of 1 and 2 were 28.3 n M and 15.1 n M.1 and 2 have a wide tissue distribution with Vss/F were 3.2-3.6 L/kg and 2.5-3.2 L/kg and about 1%undergo oxidative metabolism.1 and 2 were predominantly excreted by kidney in the form of unchanged compounds with f_e-U were 67.4%and 61.9%.After administration of Lianhua Qingwen,the pharmacokinetic characteristics of 1 and 2 were species similarities between human and rats.1and 2 have a wide tissue distribution with Vss/F were 7.1 L/kg and 7.6 L/kg in rats.The concentrations of 1 and 2 in the rat lung and heart tissues were about 15 times and 5 times higher than it in the plasma.On humanβ₁ adrenaline receptors（β₁-AR）,the rank order of potency(EC₅₀)was ephedrine（1.4μM）,pseudoephedrine（425μM）.On humanβ₂ adrenaline receptors（β₂-AR）,the rank order of potency(EC₅₀)was ephedrine（0.27μM）,pseudoephedrine（87μM）.Based on the rat tissue distribution results,the concentration of 1 in human lung tissue can reach the EC₅₀ value ofβ₂-AR,the concentration in human heart is less than the EC₅₀ value ofβ₁-AR;the tissue concentration of 2 is less than EC₅₀ value both onβ₁-AR andβ₂-AR.1 may be the therapeutic compound of Zhi-Mahuang in Lianhua Qingwen capsule.The main systematic exposure compounds,1 and 2,may not cause adverse effects at the lable dose of Lianhua Qingwen capsule.Conclusion:This study clarified the content of Zhi-Mahuang compounds in Lianhua Qingwen capsule,and the quality consistency of the daily dose of more than 1μmol/day was good.The systemic exposure compounds were ephedrine and pseudoephedrine after dosing Lianhua Qingwen in human,which are widely distributed in tissues with weak metabolism and mainly excreted in unchanged form through urine.The rat tissue distribution studies based on interspecies similarities widely distributed in lungs and heart.In vitro studies of humanβ₂-AR andβ₁-AR showed that both ephedrine and pseudoephedrine are active and ephedrine is highly active on both targets.In vivo pharmacocharacteristics and in vitro adrenergic agonist activities of ephedrine and pseudoephedrine suggest that therapeutic effects can be achieved at clinical doses of Lianhua Qingwen capsules without potential adverse reactions.This investigation was to provide the pharmacokinetic and pharmacodynamic information of Zhi-mahuang compounds for further researches on bridging the gap between pharmacokinetics and pharmacodynamics of the herb and clarifying the compounds responsible for the Mahuang-related therapeutic and adverse effects.