Experimental Study Of Hematopoietic Regulation Of Radix Phodiolae Polyosein Myelosuppressed Mice

Objective:Integripetal rhodiola herb is crassulaceae perennial herb or deuto-arboret, it's a valuable medicinal plant,entire plant can be used as drug.Compendium of Materia Medica record that integripetal rhodiola herb can support healthy energy,invigorate Qi, nourish blood,moistening lung,and so on.By contemporary pharmacological research,it was found that Integripetal rhodiola herb have multiple pharmacological action,including regulating the hematopoietic system,cardiovascular system,central nervous system, immune system,and so on.Integripetal rhodiola herb have been used to treat some diseases,such as high blood pressure,heart disease,diabetes,hypoxia,neurastheria, endocrine dyscrasia,menopause syndrome,brain fag,apolexis,memory subsidence, tumor etc.At present,there were few more reports about the effect of integripetal rhodiola herb and its extractive on hematopoiesis.Most of the study focus on Salidroside, the main component of integripetal rhodiola herb,while seldom on Radix phodiolae polyose.In the present study,our aim is to make sure whether Radix phodiolae polyose can promote the proliferation of bone marrow hematopoietic stem cells(HSCs),further hasten the recovery of bone marrow hematopoietic function in myelosuppressed mice. Then we explore the effect of Radix phodiolae polyose on hematopoietic regulation and its mechanisms and provide the experimental data for the clinic use and exploitation.Methods:In the present study,the model of myelosuppressed mice was prepared by ⁶⁰Co irradiation and cyclophosphamide.Peripheral blood cells and bone marrow nucleated cells counting,bone marrow morph observation,flow cytometry,hemopoietic progenitor cell culture,immunohistochemistry and western blot were used to analyze the survival and proliferation of HSCs and MSC(marrow stroma cell),cell cycle of bone marrow nucleated cells,and the expressions of apoptosis-related protein,respectively.Results:within the range of certain dosage or concentration:(1) Radix phodiolae polyose could elevate obviously the number of red blood cells (RBC),white blood cells(WBC) and hemoglobin(HB) in a dose-dependent manner in myelosuppressed mice.While radix phodiolae polyose failed to promote evidently the increase of platelets.In addition,radix phodiolae polyose could promote the increase of the number of bone marrow cells(BMCs) obviously.(2) Radix phodiolae polyose could promote the entry of BMC into cell cycle,decrease the cell proportion of G₀/G₁ phase,while increase the cell proportion of S phase and G₂/M phase in myelosuppressed mice.With the increase of dosage,the cell proportion of G₀/G₁ phase decreased and the cell proportion of S phase and G₂/M phase increased,and resulted in the increase of proliferation index(PI) of BMC.(3) Radix phodiolae polyose could promote effectively both in vivo and in vitro the colony formation of burst-forming unit-erythroid(BFU-E),colony-forming unit-erythroid(CFU-E),colony-forming unit-granulocyte macrophage(CFU-GM), but fail to promote colony-forming unit-megakaryocte(CFU-Meg).Also,radix phodiolae polyose could promote obviously the prolifer- ation of marrow stroma cells in vitro within the range of 200 ug/ml concentration.(4) Radix phodiolae polyose could reduce obviously the expressions of apoptosis related protein caspase-3,fas and fasL in myelosuppressed mice,inhibit apoptosis to maintain cells survival.Conclusions:Within the range of certain dosage or concentration:Radix phodiolae polyose could promote the recovery of hematopoietic function in myelosuppressed mice by elevating the number of peripheral blood,accelerating G₀/G₁-S phase and S-G₂/M phase transition,promoting the proliferation of HSCs and MSC,reducing the expressions of apoptosis proteinspase-3,fas and fasL.Radix phodiolae polyose make a positive effection on haematopoiesis regulation in myelosuppressed mice.