Abstract:AIM: To investigate the protective effect of Jianpi Bushen Yishi Formula on dry age-related macular degeneration(dARMD)induced by sodium iodate in mice and its mechanism.
METHODS: A total of 27 SPF male C57BL/6 mice were randomly divided into blank, model and traditional Chinese medicine groups, with 9 in each group, the structure and morphology of the retina were observed by Hematoxylin-Ehong(HE)staining, and the intracellular reactive oxygen species(ROS)in the retina were observed by fluorescence staining with dihydroethidium(DHE). In addition, malondialdehyde(MDA)and superoxide dismutase(SOD)expression levels in mouse retina were detected by biochemical kit, and expression levels of silent information regulator type 1(SIRT1)and peroxisome proliferator-activated receptor-γ coactivator 1-α(PGC-1α)protein in mouse retina were detected by Western blot.
RESULTS: Retinal structure and morphology of the model group showed a slight or mild decrease in the number of cells in the outer nuclear layer, a localized thinning of the outer nuclear layer, an inconspicuous demarcation between the outer and outer membranes, a slight or mild swelling of retinal pigment epithelial cells, and a slight or mild disturbance in the arrangement of retinal cells; while retinal pigment epithelial cells and photoreceptor layers in the traditional Chinese medicine group were significantly improved. DHE staining fluorescence results showed that the ROS level in the model group was significantly higher than that in the blank group at 14 d after modeling(P<0.01); the ROS level in the traditional Chinese medicine group was significantly lower than that in the model group(P<0.001). ELISA showed that the SOD level of the model group was significantly lower than that of the blank group at 14 d after modeling(P<0.01), and the MDA level was significantly increased(P<0.01)in the model group compared with the blank group; the SOD level was significantly higher(P<0.01), and the MDA level was significantly lower(P<0.01)in the traditional Chinese medicine group compared with the model group. Western blot results showed that the expression of SIRT1 and PGC-1α in the model group was significantly lower compared with that in the blank group(P<0.01), and the expression of SIRT1 and PGC-1α in the traditional Chinese medicine group was significantly higher compared with that in the model group at 7 and 14 d after modeling(P<0.01).
CONCLUSION: The Chinese herbal medicine, which strengthens the spleen, tonifies the kidney and benefits the eyesight, can improve the oxidative stress state of the retina induced by sodium iodate in mice and reduce the damage to the retinal tissues, which may exert the anti-oxidative stress effect through the PGC-1α/SIRT1 signaling pathway.