Proceedings of The Physiological Society

Europhysiology 2018 (London, UK) (2018) Proc Physiol Soc 41, PCB257

Poster Communications

L-Arginine supplementation with Carbamazepine improves cognition in male Sprague-Dawley rats

A. W. Olusanya1, A. P. Arikawe2, J. O. Odoka2, J. O. Leigh1

1. Department of Pharmacology, Therapeutics and Toxicology, College of Medicine, University of Lagos, Idi-Araba, Lagos, Nigeria. 2. Physiology, College of Medicine, University of Lagos, Lagos, Lagos, Nigeria.

Oxidative stress has been linked to the development of cognitive impairment in various experimental models. Carbamazepine has been associated with cognitive impairment and oxidative stress. This study investigated the effects of add-on L-Arginine; an antioxidant on cognition and oxidative stress in male non-epileptic rats. Adult male Sprague-Dawley rats from the colony in the animal facilities of the College of Medicine, University of Lagos, Idi-Araba campus were housed in groups of six per cage and were divided into 4 groups; (1) Control treated with distilled water., (2) L-Arginine treated with L-Arginine (100mg/kg BW) in distilled water., (3) Carbamazepine treated with carbamazepine (25mg/kg BW twice daily) in distilled water., (4) L-Arginine + Carbamazepine treated with L-Arginine and Carbamazepine as above for two weeks to assess the acute changes in cognition and oxidative stress markers. Carbamazepine (Tegretol) was obtained from Novartis Pharma AG, Basle, Switzerland while L-Arginine was obtained from Now Foods, Bloomingdale, USA. All animals had free access to normal rat chow throughout the experiment. At two weeks of treatment, cognition was assessed using the Y maze. The rats were anaesthetized after cognition assessment with tribromoethanol (2, 2, 2-tribromoethanol, Aldrich), humanely sacrificed with the hippocampus and frontal lobes isolated from the whole brain and subsequently homogenized for assessment of oxidative stress markers (Catalase, superoxide dismutase (SOD), malondialdehyde (MDA), and reduced Glutathione (GSH). The number of arm entry and correct alternation were significantly higher (p < 0.05) in the L-Arginine and L-Arginine + Carbamazepine groups. In the frontal lobe, L-Arginine significantly increased (p < 0.05) catalase and GSH levels and no significant difference in SOD and MDA levels. Carbamazepine significantly increased (p < 0.05) SOD in the frontal lobe with no significant change in catalase and GSH levels. L-arginine + carbamazepine significantly (p < 0.05) increased glutathione levels and reduced SOD levels however there was no significant difference in the levels of catalase and MDA. In the hippocampus, L-Arginine significantly (p < 0.05) reduced MDA with no change in other parameters. Carbamazepine significantly reduced (p < 0.05) glutathione (GSH) levels but no significant change in catalase, SOD and MDA levels. SOD and MDA level were significantly lower (p < 0.05) in the L-Arginine + Carbamazepine group compared to other groups, GSH was also significantly higher (p < 0.05) in this group and catalase level was not significantly different in all the groups. Oral L-Arginine supplementation (100mg/kg BW) with carbamazepine improved performance on Y maze and also enhanced the cognitive process in the frontal lobe and hippocampus of male rats.

Where applicable, experiments conform with Society ethical requirements