Study On The Neuroprotective Effect Of Fish Oil-rich Diet On Rats With Mild Blast-related Traumatic Brain Injury

Context:Fish oil is a kind of polyunsaturated fatty acid,which has a variety of biological activities such as lowering blood pressure and regulating blood lipids,promoting fatty acid metabolism and clearing thrombi,and providing essential nutrients for maintaining normal metabolism and function of human body.Over the past few decades,fish oil has been widely shown to improve the nervous system by promoting the development of brain cells and neurons,especially in models of neurodegeneration and psychiatric disorders.Objectives:The aim of this study was to explore the neuropathological changes and process brain astrocyte microglia and neuron injury in rats at different time after mild blast-related traumatic brain injury(b TBI).Therefore,we investigated the neuroprotective potential of dietary supplementation with fish oil on mild b TBI rats.Methods:Fifty-four newly weaned SD rats were randomly divided into control group(n=18),model group(n=18)and treatment group(n=18).The model group and treatment group were fed with ordinary diet and oil-rich diet for 33 days to establish the mild b TBI model by shock wave,respectively.The control group rats were fed with ordinary diet and received the same surgical treatment as the other two groups except that they did not receive shock wave injury.After that,the brain tissues were collected at 6h,24 h and 3d after injury and stained with Hematoxylin-eosin(HE staining)for cell survival analysis.The changes of astrocyte marker GFAP,microglia marker Iba-1,and the staining of Fuoro-Jade B(FJ-B)after acute neuron injury in rats were detected respectively as well.Results:There was no difference in pre-injury weight gain between groups.The weight of rats after injury showed a decreasing trend,however,there was no significant difference in the degree of weight loss and recovery(p>0.05).The number of GFAP positive staining astrocytes and nerve cells in hippocampus after 6h,24 h and 3d mild b TBI were significantly reduced compared with control group(p<0.01).Compared with the model group,the number of astrocytes in hippocampus after injury is relatively high in the treatment group(p<0.01)There was no significant difference among different groups at each time point;Compared with the treatment group,the number of activated microglia and injured neurons in the hippocampus of the model group increased significantly at 6h after injury,and the number of activated microglia and injured neurons increased gradually at 24 h and 3d after injury,showing a significant difference(p<0.01).Conclusion:Mild b TBI can cause characteristic changes in brain histopathology and neuronal cell loss.Activation of astrocytes and microglia may have protective effects on neurons.Pre-injury dietary supplementation with fish oil shows neuroprotective benefits in alleviating neurons injury and inhibiting neuroinflammatory response in a rat model of mild b TBI.