A critical courier role of volatile oils from Dalbergia odorifera for cardiac protection in vivo by QiShenYiQi.

Component-based Chinese medicine (CCM) is derived from traditional Chinese medicine but produced with modern pharmaceutical standard and clearer clinical indications. However, it still faces challenges of defining individual component contribution in the complex formula. Using QiShenYiQi (QSYQ) as a model CCM, we investigated the role of Dalbergia odorifera (DO), an herbal component, in preventing myocardial damage. We showed that in vitro, QSYQ exerted considerable protective activities on cardiomyocytes from HO-induced mitochondrial dysfunction with or without DO. However, in isolated rat hearts, myocardial protection by QSYQ was significantly weakened without DO. In everted gut sac model, DO significantly enhanced absorption of the major QSYQ ingredients in different regions of rat intestine. Finally, in in vivo mouse model of doxorubicin (DOX)-induced myocardial damage, only QSYQ, but not QiShenYiQi without DO (QSYQ-DO), exerted a full protection. Taken together, our results showed that instead of directly contributing to the myocardial protection, Dalbergia odorifera facilitates the major active ingredients absorption and increases their efficacy, eventually enhancing the in vivo potency of QSYQ. These findings may shed new lights on our understanding of the prescription compatibility theory, as well as the impacts of "courier herbs" in component-based Chinese medicine.