Effects of a High-Fat Diet on Neuroinflammation and Apoptosis in Acute Stage After Moderate Traumatic Brain Injury in Rats.

Abstract

A high-fat diet (HFD) is correlated with a higher risk of metabolic syndrome. The effect of HFD on neuroinflammation and apoptosis in acute stage after traumatic brain injury (TBI) in rats is not well known. Five-week-old male Sprague-Dawley (SD) rats were fed a HFD or normal diet (ND) for 8weeks. Anesthetized male SD rats were divided into two subgroups: sham-operated and TBI. Motor function was measured using an inclined plane. The numbers of apoptotic neurons (markers Neu-N, TUNEL, caspase-3), activated astrocytes (marker GFAP) and microglia (marker OX42), and TNF-α expression in microglia and astrocytes in the ischemic cortex were investigated using an immunofluorescence assay. All of the parameters were measured on the 3rd day after TBI. Rats fed a HFD for 8weeks had higher body weight, serum cholesterol, and triglycerides. TBI-induced motor deficits, neuronal decrease, neuronal apoptosis, astrocyte and microglia activation, and TNF-α expression in microglia and astrocytes in the ischemia cortex were significantly increased in ND and HFD rats compared to sham rats. However, these parameters were not significantly different between the ND and HFD TBI groups, except motor deficit. HFD has no significant effects on neuronal apoptosis or neuroinflammation in acute stage compared with ND for 8weeks after moderate TBI in experimental rats.