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      Saponins from Aralia taibaiensis Attenuate D-Galactose-Induced Aging in Rats by Activating FOXO3a and Nrf2 Pathways

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          Reactive oxygen species (ROS) are closely related to the aging process. In our previous studies, we found that the saponins from Aralia taibaiensis have potent antioxidant activity, suggesting the potential protective activity on the aging. However, the protective effect of the saponins and the possible underlying molecular mechanism remain unknown. In the present study, we employed a D-galactose-induced aging rat model to investigate the protective effect of the saponins. We found that D-galactose treatment induced obvious aging-related changes such as the decreased thymus and spleen coefficients, the increased advanced glycation end products (AGEs) level, senescence-associated β -galactosidase (SA β -gal) activity, and malondialdehyde (MDA) level. Further results showed that Forkhead box O3a (FOXO3a), nuclear factor-erythroid 2-related factor 2 (Nrf2), and their targeted antioxidants such as superoxide dismutase 2 (SOD2), catalase (CAT), glutathione reductase (GR), glutathione (GSH), glutamate-cysteine ligase (GCL), and heme oxygenase 1 (HO-1) were all inhibited in the aging rats induced by D-galactose treatment. Saponins supplementation showed effective protection on these changes. These results demonstrate that saponins from Aralia taibaiensis attenuate the D-galactose-induced rat aging. By activating FOXO3a and Nrf2 pathways, saponins increase their downstream multiple antioxidants expression and function, at least in part contributing to the protection on the D-galactose-induced aging in rats.

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                Author and article information

                Oxid Med Cell Longev
                Oxid Med Cell Longev
                Oxidative Medicine and Cellular Longevity
                Hindawi Publishing Corporation
                22 January 2014
                : 2014
                1Department of Geriatrics, The Second Affiliated Hospital of Medicine School, The Xi'an Jiaotong University, Xi'an 710004, China
                2Department of Toxicology, The Key Laboratory of Free Radical Biology and Medicine of Shaanxi Province, The Center of Prevention and Treatment on ROS-Induced Injury of FMMU, School of Preventive Medicine, The Fourth Military Medical University, Xi'an 710032, China
                3School of Life Science, Shaanxi Normal University, Xi'an 710062, China
                Author notes
                *Jin-Gang Li: jingang@ 123456snnu.edu.cn and

                Academic Editor: Antonio Ayala

                Copyright © 2014 Ying-Na Li et al.

                This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

                Research Article

                Molecular medicine


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