Abstract
BACKGROUND: This study aimed to investigate the cognitive and neuroanatomical effects of chronic high fructose corn syrup (HFCS) consumption in aged male rats under different dietary intake levels. MATERIALS AND METHODS: Thirty-three 15-month-old male Sprague Dawley rats were divided into three groups: a control group (fed 20 g chow/day, n = 11), a pellet-resticted (Per)+HFCS group (11% HFCS solution and fed 10 g chow/day, n = 11), and HFCS group (11% HFCS solution and 20 g chow/day, n = 11). The HFCS groups received an 11% weight/volume HFCS solution for 16 weeks. This study assessed long-term spatial memory retention using an eight-arm radial maze and short-term working memory using a Ymaze. Motor coordination was evaluated through a locomotor activity test. Total brain and hippocampal volumes were analyzed using the ImageJ program. RESULTS: Per+HFCS rats consumed more HFCS and gained more weight than the other groups (p < 0.05). No significant differences were found among groups in locomotor activity or Y-maze performance (p > 0.05). Similarly, there were no significant differences in working memory errors (WME) or reference memory errors (RME) at 48, 72, 96, 120, or 144 hours in the spatial memory assessments of aged rats (p > 0.05). However, the HFCS group completed the eight-arm radial maze faster at 48 hours (p = 0.0467; 95% CI [0.87, 1.18]). No significant differences were observed in hippocampal or total brain volumes between groups (p > 0.05). CONCLUSION: These findings indicate that 11% HFCS consumption at different levels of food intake did not adversely affect learning, memory, or hippocampal and total brain volumes in aged rats. Chronic HFCS intake in late life, regardless of food intake, appeared to have no significant impact on neurocognitive performance. Future studies should further investigate how varying HFCS concentrations influence cognitive function and brain structure in aging models, independent of circadian feeding patterns or total caloric load. CLINICAL TRIAL NUMBER: Not applicable.