Aging is associated with
Alzheimer's disease (AD),
cardiovascular disease and
cancer. Oxidative stress is considered as a major factor that accelerates the aging process. To understand the ability of lactic acid bacteria to ameliorate memory impairment caused by aging, we investigated the effect of Lactobacillus pentosus var. plantarum (C29), which is known to protect against
scopolamine-induced memory impairment, on oxidative stress (
D-galactose)-induced memory impairment in mice.
D-Galactose was subcutaneously injected to 20-week old male C57BL/6J mice for 10 weeks, with
oral administration of C29 for the final 5 weeks. Excessive intake of
D-galactose not only impaired memory, which was indicated by passive avoidance, Y-maze, and Morris water-maze tasks, but also reduced the expression of
brain-derived neurotrophic factor (
BDNF) and hippocampal doublecortin (DCX) and the activation of
cAMP response element-binding protein (CREB). C29 treatment ameliorated
D-galactose-induced memory impairment and reversed the suppression of
BDNF and DCX expression and CREB activation. Moreover, C29 decreased the expression of a senescence marker p16 and
inflammation markers p-p65, p-FOXO3a,
cyclooxygenase (COX)-2, and inducible
NO synthase (iNOS). C29 treatment inhibited
D-galactose-induced expression of M1 polarization
markers tumor necrosis factor-α and
arginase II, and attenuated the
d-galactose-suppressed expression of M2 markers
IL-10,
arginase I and CD206. Taken together, these findings suggest that C29 may ameliorate memory impairment and M1 macrophage-polarized
inflammation caused by aging.