Abstract:Objective To investigate the effects of Panax notoginsenosides (PNSs) on primitive and definitivehematopoiesis of zebrafish embryos, and provide new insights into pharmacological application of PNSs. Methods PNSswere obtained by ethanol extraction from panax notoginseng powder. Zebrafish embryos were treated with 50 or 100 μg/ mLPNSs from the 75% epiboly stage until harvest to detect hematopoietic markers by in situ hybridization. Results Comparedwith the control larvae, the embryos treated with PNSs exhibited obviously reduced expression of primitive hematopoieticmarkers such as gata1 and hbbe3. Consistently, the formation of erythrocytes was also impaired in the PNSs-treated embryosat later stages. Furthermore, PNSs treatments disrupted the definitive hematopoiesis as indicated by decreased expression ofhematopoietic stem cell markers runx1 and cmyb and the T lymphocyte marker rag1. Interestingly, the inhibitory effects ofPNSs on the primitive and definitive hematopoiesis were concentration-dependent. Conclusions Our results indicate thatPNSs impair primitive and definitive hematopoiesis during zebrafish embryonic development, implying that PNSs should be used with caution during pregnancy.