Agmatine administration alleviates nerve damage and improves nerve function in methotrexate induced peripheral neuropathy in rats

Objective: Chemotherapeutic agents can produce neurodegenerative changes. This study was conducted to assess the therapeutic potential of agmatine, a neuromodulator, on methotrexate induced neurodegeneration in sciatic nerve. Materials and Methods: 40 male Wistar albino rats were assigned into four groups at random as control, methotrexate, agmatine and methotrexate-agmatine. Methotrexate was injected intraperitoneally at a 37.5 mg/kg/week dose for 3 weeks. Afterwards, agmatine was administered intraperitoneally twice a day at a 40 mg/kg dose for 7 days. Sciatic functional index, nociceptive pain perception and behavioral changes were analyzed every week. Nerve conduction velocity was evaluated. Apoptotic activity and mitophagy, histopathological changes in sciatic nerves were examined. Results: Methotrexate administration resulted in a prolonged escape time to the platform and decreased the time spent in the quadrant in the water maze test; elevated nociceptive latencies; decreased the number of frames passed in the open field test; reduced sciatic NCV and SFI score. Besides, methotrexate administration caused a reduction in myelin thickness and axon diameter in sciatic nerve and a more intense glial fibrillary acidic protein immunoreactivity. Methotrexate administration triggered an increase in the Bax/Bcl-2 protein expression ratio without changing the expression level of Parkin, indicating a slight apoptotic activation. agmatine administration improved methotrexate induced changes in behavioral performances, nociceptive pain perception, nerve conduction, SFI scores and histopathological changes. Conclusion: Agmatine has been demonstrated to possess a therapeutic potential in methotrexate induced degeneration and peripheral neuropathy in the rat sciatic nerve.