The Middle Asian tortoise (Testudo horsfieldii) is one of the most radio-resistant animals (LD 50/30 – 500Gy). The crude extract originated from the spleen significantly increases the survival of mice treated with lethal doses of irradiation.
We have prepared extracts from different organs of the tortoise and evaluated their biological activity.
A crude extract isolated from the spleen of the tortoise was administered to mice that were further treated with lethal doses of irradiation. In an iterative process, the crude extract was submitted to a number of chromatography purification steps side by side with biological activity screening of the so obtained fractions. Various vital parameters were monitored: 1- Peripheral blood leukocytes, 2-Spleen colonies, 3-mitosis in bone marrow, 4- survival after 30 days. The process finished up with the isolation, characterization and synthesis of the tetrapeptide FTGN. The peptide accelerates the repopulation of the irradiated bone marrow at very low concentrations both in vivo and ex-vivo. Interestingly, the peptide protects the animals from alopecia.
The studies in experimental animals suggest that treatment with FTGN can potentially benefit patients who suffer bone marrow (BM) damage due to radiotherapy or chemotherapy as well as patients undergoing autologous or allogenic BM transplantation.