Aqueous extract of pomegranate enriched in ellagitannins prevents anxiety-like behavior and metabolic changes induced by cafeteria diet in an animal model of menopause

Women around menopause are vulnerable to present psychiatric and metabolic disorders; thus, therapies that contribute to treat both pathologies are required. Previous reports showed that an aqueous extract of pomegranate (Punica granatum), enriched in ellagitannins, exerts an antidepressant-like effect in ovariectomized rats. We analyze whether this aqueous extract of P. granatum (AE-PG) prevents the anxiety-like behavior induced by a cafeteria diet (CAF) in middle-aged ovariectomized rats at the same time that it prevents an increase in body weight, glucose, lipids, and the changes on mRNA expression of the peroxisome proliferator-activated receptor gamma (PPAR-gamma) in the liver. Also, the effects of AE-PG on the protein levels of PPAR-gamma phospho-PPAR-gamma, extracellular signal-regulated protein kinase (ERK1/2) and phospho-ERK1/2 were measured in the hippocampus and amygdala. CAF induced anxiety-like behavior, augmented lipids and glucose blood levels, body weight, visceral fat, insulin resistance, and decreased mRNA expression of PPAR-gamma in the liver. In rats fed with the CAF, AE-PG prevented the anxiety-like behavior, reduced body weight, lowered lipid levels, reduced insulin resistance, and increased PPAR-gamma mRNA expression in the liver. In the hippocampus, ERK1/2 but not PPAR-gamma protein levels were decreased by CAF, while AE-PG prevented these effects. In the amygdala, CAF increased the phosphorylation of PPAR gamma, and AE-PG prevented it. In contrast, AE-PG rescued the decreased ERK1/2 protein level in the hippo campus caused by CAF. In conclusion, AE-PG treatment prevented anxiogenic and metabolic effects induced by CAF, and its effects appear to be mediated by ERK1/2 and PPAR gamma depending on the brain area studied.