Effect of glycine: Studying memory and behavioral changes in mice

Abstract

Glycine is an important chemical mediator of nervous system that plays a vital role in memory and other neurological functions. Therefore, the effect of glycine on these traits must be studied to understand biological mechanisms of intricate neurological system. We investigated the effect of different doses of glycine on memory and behavior using 30 albino mice models (treated and control). After two weeks of glycine dosing, we performed light and dark activity and novel-object recognition (NOR) tests to assess the cognitive traits. Brain and blood samples were taken and kept at -70°C using ultra-low temperature freezer. Neurochemical estimation of blood glycine level was estimated by high-performance liquid chromatography with electrochemical detectors (HPLC-ECD). Concentration of glycine (100, 300 and 500 mg/kg) is significantly observed (p<0.01) and it changes due to physiological variations in N-methyl-Daspartate (NMDA) an important neurotransmitter for memory. We observed significant increase in serotonin metabolites including 5-hydroxy tryptophan (5-HT, p<0.05) and 5-hydroxy indole acetic acid (5-HIAA, p<0.001) levels. Similarly, effects were found in case of dopamine (DA, p<0.05) and its metabolites: 3, 4- ihydroxyphenylacetic acid (DOPAC, p<0.001) and homovanillic acid (HVA, p<0.001). Histopathological investigation of brain tissues showed cellular clumps at cortical junctions at higher doses of glycine as compared to control. These findings revealed that dose dependent concentration of glycine can be useful for memory loss and behavior deficits.