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

OBJECTIVE: To investigate the effect of energy intake restriction on postoperative cognitive dysfunction (POCD) after internal fixation of tibial fractures in mice. METHODS: 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. RESULTS: 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-1ß, 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. CONCLUSION: 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.

Enhanced Antitumor Activity of Lidocaine Nanoparticles Encapsulated by a Self-Assembling Peptide.

Although local anesthetics (LAs) such as lidocaine have been traditionally used for pain relief, their antitumor activity has attracted more and more attentions in recent years. However, since nearly all LAs used in clinic are in their hydrochloride forms with small molecular weight and high water-solubility, their fast absorption and clearance greatly limit their antitumor activity in vivo. To better exploit the antitumor activity of LAs, lidocaine nanoparticles (LNPs) are prepared by using a self-assembling peptide to encapsulate the hydrophobic base form of lidocaine. In cultured A375 human melanoma cells, the LNPs show much higher cellular uptake level than the clinic formulation of lidocaine hydrochloride, which leads to enhanced efficacy in inhibiting the proliferation, migration and invasion of the cells, as well as in inducing cell apoptosis. Compared with lidocaine hydrochloride, LNPs can also significantly slow down the release rate of lidocaine. In nude mice, LNPs can effectively inhibit the development of solid tumors from seeded A375 cells and prevent the recurrence of tumors after surgical excision. These results indicate that by using self-assembling peptide to fabricate nanoparticle formulations of local anesthetics, their antitumor activity can be significantly enhanced, suggesting a potential postoperative treatment to prevent tumor recurrence after surgical excision.

Teniposide ameliorates bone cancer nociception in rats via the P2X7 receptor.

Bone pain associated with advanced tumor metastasis is the most severe threat to life quality of patients. Highly efficient and low-toxic therapeutics is of urgent need for this complication. Bone tumor metastasis was established by direct bone inoculation of Walker 256 mammary gland carcinoma cells. Bone nociception was measured by mechanical allodynia, thermal hyperalgesia and spontaneous flinches. P2X7R level was determined by immunoblotting. The inward current was recorded by a patch clamp. The related cytokines were determined by ELISA. Our results showed that teniposide (TN) treatment significantly ameliorated bone nociception associated with tumor inoculation to a comparable extent with P2X7-specific inhibitor, BBG, in rat model. The efficient blockade of inward current generation and pro-inflammatory cytokines secretion were observed upon administration with TN. Our data highlighted the therapeutic potency of TN in this complication associated with tumor metastasis and warrants further clinical investigations.