Abstract:Objective: To explore the effect of hyperbaric oxygen (HBO) on apoptosis in hippocampus of rats with sepsis-related encephalopathy (SAE) by regulating the Toll-like receptor 4 (TLR4)/nuclear factor (NF)-κB pathway. Methods: 45 rats were randomly divided into control group, SAE group and SAE+HBO group (n=15). The SAE model was constructed by intraperitoneal injection of LPS (15 mg/kg, 3 days). Rats in SAE+HBO group received HBO intervention daily. The cranial nerve function, hippocampal neuron damage, apoptosis, and inflammatory response levels in each group were tested and compared. TLR4 and NF-κB transcription and translation levels in the hippocampus were detected. Results: The above indicators of the three groups of rats were significantly different (P<0.05). The escape latency (44.06±5.12 s), IL-1β (76.25±8.06 pg/mL), IL-6 (91.37±10.74 pg/mL), hippocampal neuron damage and apoptosis (6.17±0.78 cells/field of view), TLR4 and NF-κB mRNA and protein levels in SAE group were significantly higher than those of the control group, and the number of crossing platforms (2.94±0.35 times) was significantly lower than that of the control group (P<0.05). The escape latency (35.86±3.06 s), IL-1β (48.68±5.21 pg/mL), IL-6 (64.47±7.06 pg/mL), hippocampal neuron damage and apoptosis (3.42±0.52 cells/field of view), TLR4 and NF-κB mRNA and protein levels in the SAE+HBO group were significantly lower than those in the SAE group, and the number of crossing platforms (4.98±0.66 times) was significantly higher than in the SAE group (P<0.05). Conclusion: HBO may alleviate the damage and apoptosis of hippocampal neurons caused by SAE by inhibiting the TLR4 /NF-κB pathway, thereby protecting nerve function.
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