Energy intake restriction significantly improves POCD after internal fixation of tibial fractures in mice

To investigate the effect of energy intake restriction on postoperative cognitive dysfunction (POCD) after internal fixation of tibial fractures in mice.

Thirty mice were divided into model groups of internal fixation of tibial fractures with 0%, 20%, 30% and 40% energy intake restriction and sham operation group (n = 6). Novel object recognition task and elevated plus maze test were used to assess the ability of recognition memory and anxiety-related behavior before and one week after surgery. The blood samples were collected from mice on days 1, 3 and 7 after surgery, and the mice were euthanized on the 8th day after surgery. RT-PCR and Western blot were employed to detect the expression of AMPK-SIRT1 pathway-related genes and proteins in the hippocampus. ELISA was used to detect the levels of inflammatory factors in the peripheral blood of mice. Hematoxylin-eosin (H&E) staining and immunofluorescence (IF) staining were used to detect the proliferation, differentiation and injury of hippocampal cells.

The results showed that 20% and 30% energy intake restriction significantly improved the POCD after internal fixation of tibial fractures in mice. Significantly, 30% energy intake restriction reduced the expression of AP-1, NF-κB, CD45, IBA-1, and inflammatory factors IL-1β, IL-6, IL-8 and TNF-α, and increased the expression of AMPK and SIRT1 after the operation. H&E and IF staining showed that 30% energy intake restriction reduced postoperative hippocampal neuronal damage.

Energy intake restriction can significantly improve POCD after internal fixation of tibial fractures in mice and may provide a new treatment paradigm for POCD patients.