Fig. 4
Results of bioactivity determination and hemotopoiesis investigation of rmRetn on mouse BM. a: Migration of MAECs was accelerated by rmRetn at 100 or 1000 ng/ml after incubation of 8 h compared with control (p = 0.0049 and p < 0.001, n = 3); After incubation of 4 h, 100 ng/ml group didn’t exhibit significant difference from control group (p > 0.05, n = 3), while migrated number of 1000 ng/ml group was extremely significant compared with control group (p = 0.0034, n = 3). b: CFU numbers of BM per plate in the presence of rmRetn (100 and 1 000 ng/ml) were significantly increased compared with control (p < 0.001 and p = 0.0087, n = 3). c: Total BM cell numbers of normal mice were increased significantly after continuous administeration of rmRetn for 5 days, twice per day, at the dose of 50 and 500 μg/kg compared with control (PBS) group (p < 0.001 and p = 0.0036 respectively, n = 16) except for 5 ng/kg group (p > 0.05, n = 16). While the difference didn’t exist at day 10 after continuous administration of rmRetn at all the three doses of 7 days (p > 0.05, n = 16). d: Percentage of S phase of BM cells was raised largely after continuous administeration of rmRetn for 5 days, twice per day, at the dose of 50 and 500 μg/kg compared with control (PBS) group (p < 0.001 and p = 0.0036 respectively, n = 16) except for 5 ng/kg group (p > 0.05, n = 16). While the difference didn’t exist at day 10 after continuous administration of rmRetn at all the three doses of 7 days (p > 0.05, n = 16). e: Pretreatment and postreatment of rmRetn displayed thoroughly reverse effects on mice injected with 5-fluorouracil (300 mg/kg). Adminsteration of rmRetn post 5-fluorouracil treatment prolonged the life time of animals and saved two mice from the chemotoxicity of 5-Fluorouracil compared to the zone survival in control group (with only 5-fluorouracin injected) (p = 0.024, n = 15); However, the animals with mRetn pretreatment had a shorter life span than the control animals. Although the difference between pretreatment group and control group wasn’t statistically meaningful (p > 0.05, n = 15), the difference between pre- and post-treatment group was statistically meaningful (p < 0.001, n = 15); The result indicated that post-treatment of rmRetn could protect mice from the toxicity of 5-fluorouracil and increased their survival rate