Lycopene modulates cholinergic dysfunction, Bcl-2/Bax balance, and antioxidant enzymes gene transcripts in monosodium glutamate (E621) induced neurotoxicity in a rat model

• Published in: Canadian journal of physiology and pharmacology 2016-04, Vol.94 (4), p.394-401
• Main Authors: Sadek, Kadry, Abouzed, Tarek, Nasr, Sherif
• Format: Article
• Language: English
• Subjects: Animals; Antioxidants; Antioxidants - metabolism; apoptose; apoptosis; bcl-2-Associated X Protein - genetics; Brain; Brain - drug effects; Brain - metabolism; Care and treatment; Carotenoids - pharmacology; Cholinergic Agents - pharmacology; Cholinergic mechanisms; Cholinesterases - blood; Cholinesterases - genetics; Cholinesterases - metabolism; Creatine Kinase - blood; Creatine Kinase - genetics; Creatine Kinase - metabolism; expression génique; gene expression; Gene Expression - drug effects; Gene Expression - genetics; glutamate monosodique; Glutathione - blood; Glutathione - genetics; Glutathione - metabolism; Glutathione Transferase - blood; Glutathione Transferase - genetics; Glutathione Transferase - metabolism; Health aspects; Homeostasis; L-Lactate Dehydrogenase - blood; L-Lactate Dehydrogenase - genetics; L-Lactate Dehydrogenase - metabolism; Lipid Peroxidation - drug effects; Lipid Peroxidation - genetics; Lycopene; lycopène; Male; Monosodium glutamate; Neurotoxicity; Neurotoxicity syndromes; Neurotoxicity Syndromes - blood; Neurotoxicity Syndromes - genetics; Neurotoxicity Syndromes - metabolism; neurotoxicité; oxidative stress; Oxidative Stress - drug effects; Oxidative Stress - genetics; Physiological aspects; Proto-Oncogene Proteins c-bcl-2 - genetics; Rats; Rats, Wistar; Rodents; Sodium Glutamate - pharmacology; stress oxydatif; Superoxide Dismutase - genetics
• ISSN: 0008-4212; 1205-7541
• DOI: 10.1139/cjpp-2015-0388

The effect of monosodium glutamate (MSG) on brain tissue and the relative ability of lycopene to avert these neurotoxic effects were investigated. Thirty-two male Wistar rats were distributed into 4 groups: group I, untreated (placebo); group II, injected with MSG (5 mg·kg −1 ) s.c.; group III, gastrogavaged with lycopene (10 mg·kg −1 ) p.o.; and group IV received MSG with lycopene with the same mentioned doses for 30 days. The results showed that MSG induced elevation in lipid peroxidation marker and perturbation in the antioxidant homeostasis and increased the levels of brain and serum cholinesterase (ChE), total creatine phosphokinase (CPK), creatine phosphokinase isoenzymes BB (CPK-BB), and lactate dehydrogenase (LDH). Glutathione S-transferase (GST), superoxide dismutase (SOD), and catalase (CAT) activities and gene expression were increased and glutathione content was reduced in the MSG-challenged rats, and these effects were ameliorated by lycopene. Furthermore, MSG induced apoptosis in brain tissues reflected in upregulation of pro-apoptotic Bax while lycopene upregulated the anti-apoptotic Bcl-2. Our results indicate that lycopene appears to be highly effective in relieving the toxic effects of MSG by inhibiting lipid peroxidation and inducing modifications in the activity of cholinesterase and antioxidant pathways. Interestingly, lycopene protects brain tissue by inhibiting apoptosis signaling induced by MSG.