Learning behaviour and cerebral protein kinase C, antioxidant status, lipid composition in senescence-accelerated mouse: influence of a phosphatidylcholine–vitamin B₁₂diet

Abstract

Our objective was to determine whether dietary supplementation with phosphatidylcholine (PC) plus vitamin B 12 could afford beneficial effects on biochemical and biophysical events in the brain of senescence-accelerated mouse (SAM) substrain SAMP8. We measured learning behaviour, hippocampal protein kinase C (PKC) activity, cerebral antioxidant status, phospholipid composition and fatty acid composition in 6-month-old SAMP8 and in agematched controls (SAM substrain SAMR1). In comparison with SAMR1, SAMP8 showed a significant elevation in total grading score of senescence ðP , 0 : 05Þ and a significant decline in acquisition ðP , 0 : 05Þ: SAMP8 had a lower hippocampal PKC activity and cerebral PKC-b mRNA abundance than SAMR1. SAMP8 had increased cerebral lipid peroxide levels and proportion of sphingomyelin, and a lower proportion of 20 : 4n-6 and 22 : 6n-3 in cerebral phosphtidylethanolamine than SAMR1. SAMP8 fed the PC combined with vitamin B 12 diet had an increased PKC activity and a higher proportion of 22 : 6n-3 than SAMP8 fed the control diet. These results indicate the potential benefit of PC combined with vitamin B 12 as a dietary supplement.Phosphatidylcholine: Vitamin B 12 : Protein kinase C: Senescence-accelerated mouse: Brain

High‐fat diets impede the lowering effect of cyclosporine a on rat brain lipids and interact with the expression of apolipoproteins E and J

“…TG-or PC-enriched diets have been used for their beneficial effects on central nervous system (CNS) functional disorders (24)(25)(26)(27)(28)(29)(30). The aim of this study was to determine whether these diets modified some aspects of the previously observed alterations of brain lipid metabolism in response to CsA treatment (17), and whether these diets might be useful in a preventive approach toward CsA-induced neurological and psychiatric disorders.…”

“…Such changes have been suggested to be associated with decreases in brain cholesterol and abnormalities of lipid metabolism (20)(21)(22). Vegetable n-6 polyunsaturated soybean lecithin (phosphatidylcholine: PC), rich in n-6 PUFA, seems to be a suitable dietary supplement during immunosuppressive treatment with CsA since it has been shown to reduce hypercholesterolemia (23), as well as to improve memory and possibly Alzheimer's deficits (24)(25)(26)(27). Dietary triacyglycerol (TG) supplements have no positive effect on blood cholesterol in rats, but have also been shown to improve learning (28).…”

Modulation of Signal Transduction Pathways in Senescence-Accelerated Mice P8 Strain: A Useful Tool for Alzheimer’s Disease Research

“…In the section bellow, we will consider the main features that are known to occur early in the pathogenesis of AD and which the SAMP8 strain exhibits, such as increased oxidative stress, amyloid-alterations and tau phosphorylation. Although not commented upon here, other features that have been described in AD pathogenesis have been also found in SAMP8 model as: gliosis (Lu et al, 2009), protein alterations in neurons and astrocytes (Diez-Vives et al, 2009), lower hippocampal PKC activity (Hung et al, 2001), and altered protein expression in the olfactory system (Poon et al, 2005c).…”

A Brief History of Geriatrics

“…These models have been particularly useful for exploring memory deficits (155)(156)(157)(158)(159)(160). These mice are particularly good models of mitochondrial dysfunction and free radical damage (161)(162)(163)(164). The SAMP8 mouse appears to produce its memory deficit due to an excess production of amyloid precursor protein (165)(166)(167)(168).…”