Effect of human recombinant granulocyte colony-stimulating factor on rat busulfan-induced testis injury

Granulocyte colony-stimulating factor (G-CSF) is known for proliferation and anti-apoptotic activities. We aimed to use this growth factor in busulfan-injured testis. 32 male Wistar rats were injected with a double dosage of 15 ml/kg busulfan with 14 days interval. Administration of human recombinant G-CSF (100 mu g/kg) subcutaneously was performed in two different time periods: 3 days before and 2 days after receiving busulfan, G-CSF1; and at days 14-18 of busulfan injection, G-CSF2. Animals were sacrificed at the end of week five. Histological analysis, testis weight and sperm parameters (sperm count and viability) has been checked. Expressions of DEAD (Asp-Glu-Ala-Asp) box polypeptide 4 (DDX4), deleted in azoospermia like (DAZL), transition protein 2 (TP2), proliferating cell nuclear antigen (PCNA) and 5-Bromo-20-deoxyuridine (BrdU) were assessed. Empty seminiferous tubules were apparent in the busulfan- and G-CSF2-injected rats, but not in the G-CSF1 group. The G-CSF1-treated animals showed an increase in testis weight and sperm count and viability along with high expressions of DDX4, DAZL, TP2, PCNA and BrdU; even so, the changes were reversed in the busulfan and G-CSF2 groups (for all p < 0.05). Our results revealed that G-CSF application prior to busulfan insult is a promising approach in fertility maintenance.