High maternal intake of polyunsaturated fatty acids during pregnancy in mice alters offsprings' aggressive behavior, immobility in the swim test, locomotor activity and brain protein kinase C activity

Populations in Western countries consume an excess of polyunsaturated fatty acids (PUFA), even during pregnancy. Since (n-6) PUFA is critical for brai n development, we studied whether a high maternal consumption of this fatty acid alters offsprings' affective-like behaviors and (n-6) PUFA-induced pr otein kinase C (PKC) activity in the brain. Three different strains of preg nant mice were fed isocaloric diets containing either 16% (control) or 43% (high) energy derived from fat high in (n-6) PUFA (corn oil: Balb/c and CD- I mice, or soybean oil: C3H mice) throughout gestation. From birth onward d ams and offspring were fed a nonpurified diet containing 12% energy from a variety of fats. Two- to 12-month-old female and male offspring of darns ex posed to a high (n-6) PUFA diet during pregnancy were significantly more ac tive in an open field, more aggressive in the resident-intruder test and sp ent less time immobile in the swim test than offspring of dams exposed to a control (n-6) PUFA diet. Significantly greater PKC activity in the hypotha lamus and moderately less PKC activity in the whole brain (P = 0.10) were s een in the 2-month-old female and male high (n-6) PUFA offspring compared t o controls. Our findings indicate that in utero exposure to a high (n-6) PU FA diet subsequently increases locomotor activity and aggression, and reduc es immobility in the swim test. The mechanism mediating these effects may b e linked to an increased PKC activity in the hypothalamus.