Prenatal, but not Postnatal, Curcumin Administration Rescues Neuromorphological and Cognitive Alterations in Ts65Dn Down Syndrome Mice

Abstract

The cognitive dysfunction in Down syndrome (DS) is partially caused by deficient neurogenesis during fetal stages. Curcumin enhances neurogenesis and learning and memory. We aimed to test the ability of curcumin to rescue the neuromorphological and cognitive alterations of the Ts65Dn (TS) mouse model of DS when administered prenatally or during early postnatal stages, and to evaluate whether these effects were maintained several weeks after the treatment. To evaluate the effects of prenatal curcumin administration, 65 pregnant TS females were subcutaneously treated with curcumin (300mg/kg) or vehicle from ED (Embryonic Day) 10 to PD (Postnatal Day) 2. All the analyses were performed on their TS and Control (CO) male and female progeny. At PD2, the changes in neurogenesis, cellularity, and brain weight were analyzed in 30 TS and CO pups. The long-term effects of prenatal curcumin were evaluated in another cohort of 44 TS and CO mice between PD30 and PD45. The neuromorphological effects of the early postnatal administration of curcumin were assessed on PD15 in 30 male and female TS and CO pups treated with curcumin (300mg/kg) or vehicle from PD2 to PD15. The long-term neuromorphological and cognitive effects were assessed from PD60 to PD90 in 45 mice. Data was compared by ANOVAs. Prenatal administration of curcumin increased the brain weight (+45%, P< 0.001), the density of BrdU (bromodeoxyuridine)- (+150%, P< 0.001) and DAPI (4',6-diamidino-2-phenylindole)- (+38%, P=0.005) positive cells, and produced a long-term improvement of cognition in TS (+35%, P=0.007) mice with respect to vehicle-treated mice. Postnatal administration of curcumin did not rescue any of the short- or long-term altered phenotypes of TS mice. The beneficial effects of prenatal curcumin administration to TS mice suggest that it could be a therapeutic strategy to treat DS cognitive disabilities.