Intranasal cerebrolysin improves recognition and spatial learning and memory in d-galactose model of aging in mice. Intranasal cerebrolysin reduces d-galactose-induced increase in malondialdehyde level in the brain of mice model of ageing. Intranasal cerebrolysin reduces d-galactose-induced reduction in antioxidant enzymes activity in the brain of mice model of ageing. Intranasal cerebrolysin reduces d-galactose-induced apoptosis in the brain of mice model of ageing.