Altered mitochondrial membrane lipid profile in the hipoccampus of chronic ovarian hormone-deprived rats and its putative association with mitochondrial dysfunction

ZÁRATE SANDRA; ASTIZ MARIANA; MERINO FLORENCIA; REINÉS ANALÍA; SEILICOVICH ADRIANA

Mar del Plata

Congreso; XXX Reunión Anual de la Sociedad Argentina de Investigación en Neurociencias; 2015

SAN

Functional mitochondria are key for a healthy brain and their dysfunction is involved in age-related disorders. Ovarian hormone loss during reproductive senescence is associated with mitochondrial dysfunction, brain energetic deficits and increased risk of neurodegeneration. Also, mitochondria functional integrity is highly dependent on their membrane lipid composition, mainly cardiolipin content and the nature of its acyl chains, parameters that are also affected during aging. The aim of this work was to study the putative association between previously shown mitochondrial dysfunction and their membrane lipid profile induced by chronic ovarian hormone deprivation in the hipoccampus, a highly hormone-responsive area primarily affected during aging. We analyzed membrane fatty acid composition and phospholipid content in hippoccampal mitochondria from long-term ovariectomized or sham-operated Wistar rats. Mitochondria from OVX rats showed higher levels of polyunsaturated fatty acids with similar cholesterol levels. Interestingly, they also showed lower cardiolipin content containing a higher proportion of saturated acyl side-chains, indicating abnormal cardiolipin molecular species and suggesting alterations in its remodeling.Our results indicate that OVX rat mitochondria exhibit a lipid membrane composition comparable to an aging phenotype. This lipid profile could account for mitochondrial dysfunction in the hipoccampus of chronic ovarian hormone-deprived animals.