IntroductionAlzheimer disease (AD) is neurodegenerative disease, characterized by the gradual deterioration of memory and other cognitive functions. Increase in age is a major risk factor for this disease and the prevalence of AD has increased worldwide as the elderly population of the world is increasing (1). The neuropathological hallmarks of AD brains are amyloid beta fibrils in senile plaques, neurofibrillary tangles, and neuronal loss (2). The etiopathogenesis of AD is multifactorial and it is suggested that oxidative stress has a significant role in the beginning and progression of this disease, yet the sources of free radicals and the mechanisms disrupting the redox balance remain elusive (3-5).D-Galactose is a reducing sugar found in the body. When it is present at higher levels than normal, it can be converted to galactitol by galactose oxidase, resulting in the generation of oxygen-derived free radicals (6). Chronic systemic exposure to D-galactose induces aging-related changes such as corruption of spatial learning, memory loss, neurodegeneration, and diminishing activities of antioxidant enzymes and increased production of free radicals (7-9).Capparis spinosa L. is a long-lasting shrubby plant that belongs to the family Capparidaceae and grows naturally throughout the world, especially widely in the Mediterranean basin. It has been used since ancient times for aromatic properties in cooking, and besides its use as flavoring, C. spinosa has also been used as a traditional herbal medicine for its antihypertensive, poultice, tonic, and diuretic characteristics (10). This plant has been investigated for several pharmacological effects. The bud extract of C. spinosa inhibits the replication of herpes simplex virus type 2 and upregulates the expression of proinflammatory cytokines (11). It was demonstrated that the methanol extracts of C. spinosa flowering buds have antiallergic effectiveness (12), and the lyophilized extract of C. spinosa buds shows in vitro antioxidant effectiveness Background/aim: To determine the phenolic acid levels and DNA damage protection potential of Capparis spinosa L. seed extract and to investigate the effect of the extract on cognitive impairment and oxidative stress in an Alzheimer disease mice model.
Materials and methods:Thirty BALB/c mice divided into 5 groups (control, D-galactose, D-galactose + C. spinosa 50, D-galactose + C. spinosa 100, D-galactose + C. spinosa 200) were used. Mice were administered an injection of D-galactose (100 mg/kg, subcutaneous) and orally administered C. spinosa (50, 100, or 200 mg/kg) daily for 8 weeks.Results: Syringic acid was detected and the total amount was 204.629 µg/g. Addition of 0.05 mg/mL C. spinosa extract provided significant protection against the damage of DNA bands. C. spinosa attenuated D-galactose-induced learning dysfunctions in mice and significantly increased memory retention. Malondialdehyde (MDA) levels increased and superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activities decreased in the D-...