Dexmedetomidine ameliorates diabetic cardiomyopathy by inhibiting ferroptosis through the Nrf2/GPX4 pathway.

OBJECTIVE: Dexmedetomidine (DEX) has been shown to have anti-apoptotic effects in diabetes mellitus, but its role in mitigating diabetic cardiomyopathy (DCM) through ferroptosis regulation is unclear. METHODS: An in vitro DCM model was established using H9C2 cells induced with high glucose (HG) and treated with DEX at varying doses and a nuclear factor erythroid 2-realated factor 2 (Nrf2) specific inhibitor ML385. Cell viability was evaluated using the MTT method after treatment with DEX or mannitol (MAN), and the dosage of DEX used in subsequent experimentation was determined. The effects of HG-induced high osmotic pressure were assessed using MAN as a control. Cell apoptosis was evaluated using flow cytometry. Protein levels of Bcl2, Bax, nuclear Nrf2, and glutathione peroxidase 4 (GPX4) were measured using Western blot. Superoxide dismutase (SOD) activity, malondialdehyde (MDA) levels, Fe2+ concentration and reactive oxygen species (ROS) levels were measured using corresponding kits and dichlorodihydrofluorescein diacetate, respectively. RESULTS: Treatment with DEX or MAN had no effect on H9C2 cell viability. HG induction reduced H9C2 cell viability, increased cell apoptosis, upregulated levels of Bax, Fe2+, MDA, and ROS, and downregulated Bcl2 protein levels, SOD activity, and protein levels of nuclear Nrf2 and GPX4. DEX inhibited HG-induced H9C2 cell apoptosis, promoted Nrf2 nuclear translocation, and activated the Nrf2/GPX4 pathway. Inhibition of Nrf2 partially reversed the protective effects of DEX against HG-evoked H9C2 cell injury. CONCLUSION: Our findings demonstrate that DEX attenuates HG-induced cardiomyocyte injury by inhibiting ferroptosis through the Nrf2/GPX4 pathway, providing potential therapeutic targets for DCM treatment.

Prediction of the Length of Intensive Care After Cardiac Surgery Under Cardiopulmonary Bypass: Logistic Regression Analysis Based on Troponin I And EuroSCORE II.

AIM: This study is to establish a model for patients undergoing cardiac surgery under cardiopulmonary bypass (CPB) to predict the length of intensive care. METHODS: This is a single center retrospective study. A total of 265 patients admitted to the ICU after CPB from 2016 to 2017 were enrolled in the study. Preoperative indicators, intraoperative parameters, and postoperative data were collected. Each patient was scored for EuroSCORE II before surgery. According to the length of intensive care, all patients were divided into two groups: short stay (< 72 h) and long stay (≥ 72 h). A binary logistic regression analysis was performed to establish a regression model to evaluate the predictive performance of the indicators and the EuroSCORE II scoring system on the length of the intensive care. RESULTS: Both troponin I and EuroSCORE II could predict the length of intensive care of patients undergoing cardiac surgery under CPB. After combing the two factors, the prediction efficiency was higher. Comparing the prediction results with the actual data, it showed that the method had high overall accuracy. CONCLUSIONS: The predictive model based on cTnI and EuroSCORE II can accurately predict the length of intensive care of patients undergoing cardiac surgery under CPB. This predictive model may help to improve ICU resource management.

Prethrombotic state and cardiac events in patients with coronary heart disease during noncardiac surgery.

This study aimed to investigate the significance of the prethrombotic state (PTS) and 4 plasma markers in predicting perisurgical adverse cardiac events in patients with coronary heart disease (CHD) undergoing abdominal surgery. Perioperative adverse effects were recorded in 128 consecutive patients with CHD undergoing elective abdominal surgery. Plasma d-dimer, P-selectin, von Willebrand factor (VWF), and thrombus precursor protein were measured before and after the surgery. Patients with abnormal values in one or more of the 4 PTS markers were identified as having PTS, and data were analyzed by univariate and multivariate logistic regression. Abnormal presurgery levels of the 4 markers were found more frequently in those with adverse perioperative cardiac events than in those without. Multivariate analysis showed the odds ratios for adverse cardiac events to be 64.3 (PTS, P < .001), 25.7 (VWF, P = .003), and 23.5 (P-selectin, P = .04). Preoperative PTS is an independent risk factor for perioperative events in patients with CHD undergoing noncardiac surgery.