Regulation of leucogenesis by extracellular ubiquitin in rodents after chemically induced inhibition

To study the influence of intraperitoneal injected extracellular ubiquitin on regeneration of leucopoiesis calculation of nuclear cell count in bone marrow (BM) and peripheral blood (PB) smears stained with azure-eosin was performed. In the first, control group of animals inhibition of haematopoiesis achieved by means of 100 mg/kg cyclophosphamide LD50 50–200 mg/kg injection. Bone marrow and peripheral blood samples from the first group of rats had been taken at 24, 48, 72, 96 and 168 h points after injection of cytostatic. Animals of the second, test group were injected by 200 μg/mL ubiquitin 72 h later after cytostatic injection. Our experiments revealed that ubiquitin makes corrections in regeneration of leucopoiesis and leads to normalisation of the process. Ubiquitin regulates stem cell activity, normalizes the release of functional cells into bloodstream, supposedly retains progenitor cells in zones of differentiation and maturation, and restores the nuclear cell ratio in PB and BM. We suppose that obtained results are important for elucidation of new pathways of ubiquitinylation and give us possibilities to find new therapeutics for regeneration of leucopoiesis that is very essential for treatment of radiated bone marrow and chemotherapeutic side effects in cancer patients.