Effect of proanthocyanidins on cognitive improvement in thyroxin-induced aging mice

As the population ages, functional dietary supplements are increasingly used to reduce age-related diseases, especially in the field of cognitive impairment. In this study, a thyroxine (Th)-induced aging model was established, and the effect of proanthocyanidins (Pc) on cognitive impairment of aging mice was evaluated based on cognitive ability, neuroinflammation and immune level. The results showed that Pc significantly reduced AchE activity compared to the Model group, improving learning deficits and spatial memory in aged mice (P < 0.01). Further study showed that Pc could maintain the organism's redox balance, markedly increasing T-AOC, GSH, and SOD levels (P < 0.01) while reducing MPO and MDA levels (P < 0.01). Pc also improved systemic inflammation, raising the levels of the anti-inflammatory cytokine PF4 and significantly lowering pro-inflammatory factors in the blood (P < 0.01). In the DG region of the hippocampus, Pc effectively repaired nerve damage, inhibited the over-activation of microglia and astrocytes, down-regulated GFAP and IBA-1 proteins (P < 0.01), and then reduced neuroinflammation. Additionally, Pc supplementation also significantly increased the levels of WBC, Lymph, Mid, and Gran in aged mice (P < 0.01), aiding in the recovery of leukocyte counts. At the same time, the CD3⁺ level and CD4⁺/CD8⁺ ratio were significantly increased (P < 0.01) to maintain the dynamic balance of lymphocyte subsets in aging mice and enhance the immune capacity of aging mice. The study revealed that Pc, as a dietary supplement, can effectively alleviate cognitive impairment in the elderly population. This provides a new dietary nutrition supplement strategy for the health of the aging population.