The Effect Of Catalpol And Its Mechanism On Neuroplasticity During Development And Aging

In this study, we attempt to investigate: (1) the changes and adjusting machnism of synaptic plasticity and spatial learning ability during development. (2) the effect of catalpol on cognitive and behavioral defect and presynaptic proteins and a potential mechanism during aging. (3) the effect and mechanism of catapal and training on neuroplasticity during development.We investigate the changes in the protein amount of caveolin-1, and the correlation with synaptophysin levels in various brain regions (the hippocampus, cortex and cerebellum) obtained from different age rats (1-, 4-, 22-24month rats). In the hippocampus, a concomitant decrease in caveolin-1 and synaptophysin protein levels has been observed, while in the cortex caveolin-1 and synaptophysin increased in parallel in 22-24month old rats. And in the cerebellum, there is no obvious difference in caveolin-1 and synaptophysin levels among three groups. Hippocampal synaptophysin levels are related to cognitive ability. Our results suggest caveolin-1 may play an important role on the modulating synaptic plasticity throughout life and down-regulated caveolin-1 in the hippocampus may contribute to the decrease of synaptic plasticity in physiological aging process.Behavioral tests (Y-maze and open-field test) are used to estimate the the cognitive and behavioral ability of 3 groups SD male rats (1-, 4-, 22-24 moths). We have reported a time-dependent effect of catalpol in the spatial learning and memory on Y maze. The application of catalpol reduced both the number of errors in learning and memory retention after ten days treatment, thus prevented the impairment of spatial learning, and increased memory. However, 5 days treatment only had effect on spatial memory not on learning. These results demonstrate the ability of catalpol to reverse memory deficits and further confirmed the therapeutic potential of catalpol in the treatment of cognitive deficits in aging. The evaluation of the different behavioral measures obtained in the open-field test provides clear evidence that application of catalpol induce obviously behavioral alteration. Catalpol-treated animals have displayed high scores of locomotor. And shorten entering center time that reflects exploratory motivation. These novel finding represents direct demonstration of catalpol preventing behavioral deficits of aged rats.The hippocampal levels of GAP-43 and synaptophysin in 3 groups of 4 months (young group), 22-24 months (aged group) and catalpol-treated 22-24 months (catalpol-treated group) rats are evaluated by western blotting. Results clearly show a significant decrease in synaptophysin (46.6%) and GAP-43 (61.4%) levels in the aged group against the young animals and an increase (45.0% and 31.8% respectively) in the catalpol-treated aged rats in comparison with the untreated aged group. By immunohistochemistry, furthermore, we have found that catalpol selectively enhance synaptophysin-IR within the neurons in dentate gyrus layer, while it does not affect synaptophysin-IR in CA1 and CA3 subregions of the...