Effect of High-Oleic Peanut Intake on Aging and Its Hippocampal Markers in Senescence-Accelerated Mice (SAMP8).

Kiharu Igarashi,Daisuke Kurata

doi:10.3390/nu12113461

Abstract

In many previous studies, the preventive effects of peanut against aging and cognitive impairment have often been unclear, so to clarify the effects we first investigated effective markers for evaluating its effects in the hippocampus of senescence-accelerated mouse prone/8 (SAMP8) mice, mainly using proteomics. The effects of dietary high-oleic peanuts on the hair appearance of SAMP8, the expression of effective markers in the hippocampus, and the TBARS and amino acid contents of the hippocampus were examined. Hippocampus solute carrier family 1 (glial high-affinity glutamate transporter), calcium/calmodulin-dependent protein kinase type II, and sodium- and chloride-dependent GABA transporter, which all are considered to be closely related to glutamic acid concentration were decreased by feeding of the samples, and the GABA/glutamic acid ratio in the hippocampus was increased by feeding with the samples. The formation of glial fibrillary acidic protein and synapsin-2, which showed higher levels in the SAMP8 than in SAMR1, and the protein expression of tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein and dihydropteridine reductase, which are considered to be related to the formation of adrenergic neuron transmitters, were reduced by the feeding of peanuts and their germ-rich fraction. Ferulic acid, as an ester and minor component in peanuts, could be partly connected to the effect of peanuts. These results indicate that high-oleic peanuts and their germ-rich fraction can protect against aging and cognitive impairment by regulating protein expression, which could be measured by the proteomics of the above hippocampus proteins of SAMP8 and the hippocampal GABA/glutamic acid ratio.

Highlights

Roasted peanuts, which are widely consumed as cakes containing sugars and/or other food additives, are favored by many people in Japan because of their characteristic taste and flavor, and the number of products made with them is increasing
This information prompted us to study whether high-oleic peanuts are available for protection against aging and cognitive impairments, and whether the germ-rich fraction of high-oleic peanuts released as a by-product during processing has the same effect as the wholegrains of roasted peanuts, including their action mechanism in senescence-accelerated mouse prone/8 (SAMP8)
The degree of senescence of mice given an experimental diet (Figure 2), which was calculated from the appearance of mice, such as the coarseness and yellowing of the back coat, loss of hair, and other characteristics [14], was higher in SAMP8 and was the lowest in the SAMR1 group

Summary

Introduction

Roasted peanuts, which are widely consumed as cakes containing sugars and/or other food additives, are favored by many people in Japan because of their characteristic taste and flavor, and the number of products made with them is increasing. It is reported that walnuts containing a number of potential neuroprotective compounds, such as vitamin E, folate, flavonoids, and ellagic acid, are effective in improving memory deficits in transgenic mouse models of Alzheimer’s disease These reports suggest that peanuts, which may contain the same compounds as walnuts, may be able to protect against Alzheimer’s disease, which accompanies aging [3]. The improvement in cognitive function in older women who consume nuts at a higher volume for a longer time may support the benefit of nuts in protecting against cognitive function decline and aging [4,5] This information prompted us to study whether high-oleic peanuts are available for protection against aging and cognitive impairments, and whether the germ-rich fraction of high-oleic peanuts released as a by-product during processing has the same effect as the wholegrains of roasted peanuts, including their action mechanism in SAMP8

Methods

Results

Discussion

Conclusion