EFFECT OF PRENATAL EXPOSURE TO LPS COMBINED WITH PRE- AND POST-NATAL HIGH-FAT DIET ON HIPPOCAMPUS IN RAT OFFSPRING

Objective: Prenatal exposure to lipopolysaccharide (LPS) or high-fat diet (HFD) results in hippocampal impairment and cognitive deficits in offspring rats. What is not clear is how prenatal exposure to LPS combined with pre- and post-natal HFD would affect the hippocampus in offspring rats. Methods: 32 pregnant rats were randomly divided into four groups, including control group; LPS group (pregnant rats were injected with LPS 0.4 mg/kg intraperitoneally on the 8th, 10th and 12th day of pregnancy); HFD group (maternal rats had HFD during pregnancy and the lactation period, and their pups also had HFD up to the third month of life); LPS + HFD group (rats were exposed to the identical experimental scheme with LPS group and HFD group). The serum IL-6 and TNF-alpha concentration was measured in three-month-old offspring rats in all groups. Hippocampal morphology and expressions of glial fibrillary acidic protein (GFAP), Tau and synaptophysin (SYP) in offspring rats were measured. Results: Serum IL-6 and TNF-alpha concentration in the HFD group increased significantly compared with the control group, LPS group and LPS + HFD group. Compared with the control group and the LPS + HFD group, cells in the LPS and HFD groups were smaller and arranged in disorder, and cell membrane was not complete, nucleoli and nuclear heterochromatin stained darkly with hematoxylin. GFAP and Tau expression in the hippocampus of the LPS and HFD groups increased significantly compared with the control group and LPS + HFD group. SYP expression in the LPS and HFD groups decreased significantly compared with the control group and HFD group, increased in the LPS + HFD group. Conclusion: Prenatal exposure to LPS combined with pre- and post-natal HFD result in a protective effect on the hippocampus in offspring rats, and it might be a benefit from the predictive adaptive response to prenatal inflammation. (C) 2014 IBRO. Published by Elsevier Ltd. All rights reserved.