Ameliorative effects of dietary carotenoids on memory deficits in senescence-accelerated mice (SAMP8)

Abstract We previously reported that the dietary ingestion of the red-bell pepper ( Capsicum annuum L.) or tomato ( Lycopersicon esculentum Mill.) ameliorated the age-related alteration of SAMP8. These vegetable abounds in antioxidative carotenoids, capsanthin and lycopene. We examined the effects of feeding red-bell pepper or capsanthin on the age-related disorders in the senescence-accelerated mouse (SAMP8), a murine model of the accelerated decline in learning ability, and the control SAMR1 mouse. SAMP8 mice that received a diet containing 0.1% (w/w) capsanthin showed a much better memory acquisition in passive avoidance tasks compared to those given the control diet. The ingestion of capsanthin showed no effect on the learning ability of the SAMR1 mice. The activity of choline acetyltransferase (ChAT) in the parietal cortex of SAMP8 mice fed the diet containing capsanthin was potentiated compared to that in those fed the common diet. These observations indicate that the amelioratory effect of the red-bell pepper on the learning impairment in SAMP8 mice is mainly due to capsanthin. The ingestion of lycopene (0.02% (w/w) in the diet) also ameliorated the memory deficits in the SAMP8 mice analogous to the feeding of capsanthin.