Abstract
B-lymphocytopenia among myelosuppression is the most intractable side effect of chemotherapy. Here, we investigated ways to alleviate 5-fluorouracil-caused stress hematopoietic impairment. We found that intraperitoneally injected ASP (Angelica sinensis polysaccharides) (100 mg/kg per day), one main active ingredient of Angelica sinensis, for consecutive 7 days, significantly recovered mouse bone marrow pro-B and pre-B cells, reversed the capacity of CFU-PreB colony forming, thus alleviating B cell reduction in the spleen and peripheral blood, as well as ameliorating immunoglobin from spleen and serum. The mechanism is related to the protective effects of ASP on IL-7 producing cells, including perivascular Leptin+ and CXCL12+ mesenchymal stem and progenitor cells (MSPCs), thus promoting IL-7 production, and activating IL-7R-mediated STAT5, PI3K-AKT signaling, including survival signals and EBF1, PAX5 transcription factor expression. Additionally, ASP's IL-7 promoting effect was demonstrated to be associated with maintaining osteogenesis/adipogenesis balance of MSPCs via the NRF2 antioxidant pathway. Collectively, our findings indicate that ASP reverse stress B-lymphocytopenia via improving Nrf2 signaling, promoting IL-7 production in MSPCs, and subsequently maintaining survival, proliferation, and differentiation of B cell progenitors, which may represent a promising therapeutic strategy.