OBJECTIVES: To investigate the mechanism through which N-acetylneuraminic acid (Neu5Ac) exacerbates hypoxia/reoxygenation (H/R) injury in rat cardiomyocytes (H9C2 cells). METHODS: H9C2 cells were cultured in hypoxia and glucose deprivation for 8 h followed by reoxygenation for different durations to determine the optimal reoxygenation time. Under the optimal H/R protocol, the cells were treated with 0, 5, 10, 20, 30, 40, 50, and 60 mmol/L Neu5Ac during reoxygenation to explore the optimal drug concentration. The cells were then subjected to H/R injury followed by treatment with Neu5Ac, Fer-1 (a ferroptosis inhibitor), or both. The changes in SOD activity, intracellular Fe²⁺ and lipid ROS levels in the cells were evaluated, and the cellular expressions of Nrf2, GPX4, HO-1, FSP1, and xCT proteins were detected using Western blotting. RESULTS: Following hypoxia and glucose deprivation for 8 h, the cells with reoxygenation for 6 h, as compared with other time lengths of reoxygenation except for 9 h, showed the lowest expression levels of Nrf2, GPX4, HO-1, and FSP1 proteins (P<0.001). Neu5Ac treatment of dose-dependently decreased the viability of the cells with H/R injury with an IC₅₀ of 30.07 mmol/L. Reoxygenation for 3 h with normal glucose supplementation and a Neu5Ac concentration of 30 mmol/L were selected as the optimal conditions in the subsequent experiments. The results showed that Neu5Ac could significantly increase SOD activity, Fe²⁺ and lipid ROS levels and reduce Nrf2, GPX4, HO-1, and FSP1 protein expressions in H9C2 cells with H/R injury, but its effects were significantly attenuated by treatment with Fer-1. CONCLUSIONS Neu5Ac exacerbates ferroptosis of myocardial cells with H/R injury by inhibiting the Nrf2 axis to promote the production of ROS and lipid ROS.
Ferroptosis/drug effects* ; Myocytes, Cardiac/cytology* ; Animals ; NF-E2-Related Factor 2/metabolism* ; Rats ; N-Acetylneuraminic Acid/pharmacology* ; Cell Hypoxia ; Reactive Oxygen Species/metabolism* ; Cell Line ; Myocardial Reperfusion Injury/metabolism*

Objective:To explore the effect of Bian-stone warming and ironing therapy on gastrointestinal blood flow in patients with severe cerebrovascular disease undergoing therapeutic hypothermia.Methods:From January 2023 to October 2024, 92 patients with severe cerebrovascular disease in the Neurosurgical Intensive Care Unit of Xuanwu Hospital of Capital Medical University were selected for the study using convenience sampling method. The patients were divided into a control group and an experimental group of 46 cases each according to the randomized numerical table method. Control group was given routine nursing, and experimental group carried out Bian-stone warming and ironing therapy on the basis of control group. Peak systolic velocity (PSV), end-diastolic velocity (EDV), and time-averaged mean velocity (TAMV) of the superior mesenteric artery of the two groups of patients were monitored before and after five days of intervention, respectively, and the situation of gastric retention and bowel sounds were recorded and compared between the groups.Results:PSV was higher in experimental group than in control group after intervention, and the difference was statistically significant ( P<0.05). The difference in EDV between the two groups was not statistically significant ( P>0.05). TAMV of experimental group was higher than that of control group after intervention, and the difference in TAVM before and after intervention of experimental group was smaller than that of control group, and the differences were all statistically significant ( P<0.05). The number of cases of gastric retention and weakened or disappeared bowel sounds in experimental group was less than that in control group after intervention, and the differences were all statistically significant ( P<0.05) . Conclusions:Bian-stone warming and ironing therapy improves gastrointestinal blood flow rate and reduces feeding intolerance in patients with severe cerebrovascular disease undergoing therapeutic hypothermia.

Objective:To explore the effect of Bian-stone warming and ironing therapy on gastrointestinal blood flow in patients with severe cerebrovascular disease undergoing therapeutic hypothermia.Methods:From January 2023 to October 2024, 92 patients with severe cerebrovascular disease in the Neurosurgical Intensive Care Unit of Xuanwu Hospital of Capital Medical University were selected for the study using convenience sampling method. The patients were divided into a control group and an experimental group of 46 cases each according to the randomized numerical table method. Control group was given routine nursing, and experimental group carried out Bian-stone warming and ironing therapy on the basis of control group. Peak systolic velocity (PSV), end-diastolic velocity (EDV), and time-averaged mean velocity (TAMV) of the superior mesenteric artery of the two groups of patients were monitored before and after five days of intervention, respectively, and the situation of gastric retention and bowel sounds were recorded and compared between the groups.Results:PSV was higher in experimental group than in control group after intervention, and the difference was statistically significant ( P<0.05). The difference in EDV between the two groups was not statistically significant ( P>0.05). TAMV of experimental group was higher than that of control group after intervention, and the difference in TAVM before and after intervention of experimental group was smaller than that of control group, and the differences were all statistically significant ( P<0.05). The number of cases of gastric retention and weakened or disappeared bowel sounds in experimental group was less than that in control group after intervention, and the differences were all statistically significant ( P<0.05) . Conclusions:Bian-stone warming and ironing therapy improves gastrointestinal blood flow rate and reduces feeding intolerance in patients with severe cerebrovascular disease undergoing therapeutic hypothermia.