n-stearoyltyrosine and Disease-Models--Animal

The neuroprotective effects of N-stearoyl-L-tyrosine (NSTyr) on cognitive function and neuronal plasticity during chronic cerebral hypoperfusion (CCH) in rats were investigated. After induction of CCH, NSTyr was administered daily for 3 months intraperitoneally. Cognitive functions were evaluated by Morris water maze and hippocampal long-term potentiation (LTP). Neuropathological changes were examined using light micrograph and Fluoro-Jade B staining. Neuronal plasticity was assessed by measuring the expression of MAP-2, GAP-43 and synaptophysin on hippocampal regions of rats with immunohistochemistry and western blotting. CCH resulted in significant spatial memory impairment and inhibition of LTP, and led to neurodegeneration in the CA1 region of the hippocampus in the model rats compared with the sham-operated rats. In the model rats treated with NSTyr, cognitive function improved. The expression levels of MAP-2 and synaptophysin protein in hippocampal areas in the model rats were less than those in the sham-operated rats, and increased in the model rats treated with NSTyr. However, no statistical significance of GAP-43 expression among the sham, model and NSTyr groups was observed. These data indicate that NSTyr exerts protective effects on cognitive function of rats after CCH, which may be related to the changes of neurodegeneration and neuronal plasticity in the hippocampal area of rats.

Topics: Animals; Cerebrovascular Disorders; Chronic Disease; Cognition; Disease Models, Animal; GAP-43 Protein; Hippocampus; Long-Term Potentiation; Maze Learning; Memory Disorders; Microtubule-Associated Proteins; Neuronal Plasticity; Neuroprotective Agents; Rats; Rats, Sprague-Dawley; Space Perception; Synaptophysin; Tyrosine

N-stearoyltyrosine (NsTyr), a synthesized anandamide (AEA) analogue, was evaluated for the first time in the present study for the neuroprotective effect in gerbils subjected to transient global cerebral ischemia reperfusion (IR). The extent of ischemia injury was assessed behaviorally by measuring neurological functions, passive avoidance test and Morris water maze; and histopathologically by evaluating hippocampal CA1 pyramidal damage. In addition, ischemia-induced apoptosis was examined using the terminal deoxynucleotidyl transferase-mediated UTP nick end labeling (TUNEL) method. Furthermore, in order to understand the mechanism of NsTyr's neuroprotective effect, we examined antioxidative enzymes, such as catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-PX), and non-enzymatic scavenger glutathione (GSH) and measured the levels of malondialdehyde (MDA) in hippocampus. The administration of NsTyr led to attenuation of ischemia-induced neural deficits both behaviorally and histopathologically, reduced the level of MDA, significantly increased the activity of antioxidants GSH and GSH-PX, and obviously elevated the activities of SOD and CAT. Our results suggest that NsTyr shows neuroprotective effect on global cerebral IR injury and its neuroprotective effects may be attributed to restraining DNA fragmentation, suppressing the production of free radicals and elevating antioxidant capacity.

Topics: Animals; Disease Models, Animal; Female; Gerbillinae; Ischemic Attack, Transient; Male; Neuroprotective Agents; Oxidative Stress; Tyrosine