Asoxime (HI-6) modulates ionising radiation generated oxidative stress in Wistar rat model.

   HI-6 is an antidotum suitable for treatment of intoxication by nerve agents and some other compounds acting as neurotoxins. However, the recent investigation appointed its modulation of inflammatory response as well as vegetative nervous system activity. Especially, cholinergic anti-inflammatory pathway seems to be linked with the HI-6 action on cholinergic system. The present experiments were carried out in order to assess the antioxidant effect of HI-6 in irradiated animals. In the reported experiment, male Wistar rats were irradiated by ionizing radiation (7.5 Gy, LD50/30). Animals were divided into four groups: i.e. controls (A), irradiated (B), treated with HI-6 (C), and both irradiated and treated with HI-6 (D). Ferric reducing antioxidant power (FRAP), thiobarbituric acid reactive substances (TBARS) and glutathione reductase activity were assayed in liver, spleen, plasma, and whole blood. Clinical biochemistry markers were determined in plasma samples.

   We found significantly increased FRAP levels in liver, while its levels decreased in the spleen of B group animals. Ionising radiation (B group) also significantly elevated TBARS values in spleen. HI-6 reversed FRAP and TBARS values to control levels. Glutathione reductase activity was significantly elevated in spleen and liver of animals exposed to HI-6 (C and D groups). Clinical biochemistry markers were shifted only slightly. The in vitro test confirmed the inhibitory effect of HI-6 towards acetylcholines-terase. In a conclusion, HI-6 is potent in suppressing oxidative stress and might be a promising drug in the field of radiation protection.