Jun Ding’s research while affiliated with Soochow University and other places

Purpose Ciprofol is a novel intravenous anesthetic that has been increasingly used in clinical anesthesia and sedation. Studies suggested that ciprofol reduced oxidative stress and inflammatory responses to alleviate cerebral ischemia/reperfusion (I/R) injury, but whether ciprofol protects the heart against I/R injury and the mechanisms are unknown. Herein, we assessed the effects of ciprofol on ferroptosis during myocardial I/R injury. Methods Experimental models of myocardial I/R injury in mice (ischemia for 30 min and reperfusion for 24 h) and hypoxia/reoxygenation (H/R) injury in H9c2 cardiomyocytes (hypoxia for 6 h followed by 6 h of reoxygenation) were established. Ciprofol was used prior to ischemia or hypoxia. Echocardiography, myocardial TTC staining, HE staining, DAB-enhanced Perl’s staining, transmission electron microscopy, FerroOrange staining, Liperfluo staining, JC-1 staining, Rhodamine-123 staining, DCFH-DA staining, and Western blot were performed. Cell viability, serum cardiac enzymes, and oxidative- and ferroptosis-related biomarkers were measured. HIF-1α siRNA transfection and the specific inhibitor BAY87-2243 were utilized for mechanistic investigation. Results Ciprofol treatment reduced myocardial infarct area and myocardium damage, alleviated oxidative stress and mitochondrial injury, suppressed Fe²⁺ accumulation and ferroptosis, and improved cardiac function in mice with myocardial I/R injury. Ciprofol also increased cell viability, attenuated mitochondrial damage, and reduced intracellular Fe²⁺ and lipid peroxidation in cardiomyocytes with H/R injury. Ciprofol enhanced the protein expression of HIF-1α and GPX4 and reduced the expression of ACSL4. Specifically, the protective effects of ciprofol against I/R or H/R injury were abolished by downregulating the expression of HIF-1α using siRNA transfection or the inhibitor BAY87-2243. Conclusion Ciprofol ameliorated myocardial I/R injury in mice and H/R injury in cardiomyocytes by inhibiting ferroptosis via the upregulation of HIF-1α expression.

Ischemia-reperfusion (I/R) injury is a serious clinical pathology associated with acute kidney injury (AKI). Ferroptosis is non-apoptotic cell death that is known to contribute to renal I/R injury. Dexmedetomidine (Dex) has been shown to exert anti-inflammatory and organ protective effects. This study aimed to investigate the detailed molecular mechanism of Dex protects kidneys against I/R injury through inhibiting ferroptosis. We established the I/R-induced renal injury model in mice, and OGD/R induced HEK293T cells damage in vitro. RNA-seq analysis was performed for identifying the potential therapeutic targets. RNA-seq analysis for differentially expressed genes (DEGs) reported Acyl-CoA synthetase long-chain family member 4 (ACSL4) related to ferroptosis and inflammation in I/R mice renal, which was validated in rodent renal. Liproxstatin-1, the specific small-molecule inhibitor of ferroptosis, significantly attenuated ferroptosis-mediated renal I/R injury with decreased LPO, MDA, and LDH levels, and increased GSH level. Inhibiting the activity of ACSL4 by the Rosiglitazone (ROSI) resulted in the decreased ferroptosis and inflammation, as well as reduced renal tissue damage, with decreasing LPO, MDA and LDH level, increasing GSH level, reducing COX2 and increasing GPx4 protein expression, and suppressing the TNF-α mRNA and IL-6 mRNA levels. Dex as a α2-adrenergic receptor (α2-AR) agonist performed renal protective effects against I/R-induced injury. Our results also revealed that Dex administration mitigated tissue damage, inhibited ferroptosis, and downregulated inflammation response following renal I/R injury, which were associated with the suppression of ACSL4. In addition, ACSL4 overexpression abolishes Dex-mediated protective effects on OGD/R induced ferroptosis and inflammation in HEK293T cells, and promotion of ACSL4 expression by α2-AR inhibitor significantly reversed the effects on the protective role of Dex. This present study indicated that the Dex attenuates ferroptosis-mediated renal I/R injury and inflammation by inhibiting ACSL4 via α2-AR.

Purpose: Apoptosis induced by excessive endoplasmic reticulum (ER) stress is accompanied by the occurrence and progression of myocardial ischemia/reperfusion (I/R) injury. COX-2 is also known to affect the development of I/R damage in myocardium. However, the interaction between COX-2 and ER stress in aggravating myocardial I/R lesion is not well characterized. Therefore, the purpose of our research was to explore the interaction between COX-2 and ER stress on myocardial apoptosis. Methods: The left anterior descending (LAD) coronary artery was ligatured with a 6-0# suture for 0.5 hours and subsequently subjected to reperfusion for 3 hours to simulate myocardial I/R in mice. Oxygen glucose deprivation/reoxygenation (OGD/R) was performed on H9c2 cells to construct an in vitro model of this experiment. NS398 (COX-2 specific inhibitor) and Salubrinal (Sal, ER stress inhibitor) were administered to assess the function of COX-2 and ER stress in myocardial I/R impairment. CCK-8 assay was used to evaluate the viability of H9c2 cells under different treatment conditions. TUNEL and Hoechst staining were used to detect the occurrence of apoptosis. Infarct area/area at risk and Hematoxylin-eosin stained sections were assessed after I/R. Protein expressions of glucose-regulated protein 78 (GRP78), COX-2, phosphorylation of eukaryotic translation initiation factor 2 alpha (p-eIF2α), CCAAT/enhancer-binding protein homologous protein (CHOP), and Cleaved caspase 3 in the myocardium were examined using Western blotting. Changes in Cleaved caspase 3 expression in myocardial slices were measured by immunohistochemistry. Results: Sal or NS398 partly reduced I/R-induced damage as testified by the apparent decrease in infarct size after I/R and reduced cell viability following OGD/R. Sal distinctly increased p-eIF2α, but caused decreased expression of COX-2, Cleaved caspase 3, and ER stress-associated proteins after I/R, suggesting that Sal effectively inhibited ER stress, apoptosis, and COX-2. Pretreatment with NS398 blocked I/R or OGD/R-induced upregulation of COX-2, Cleaved caspase 3, and ER stress-related marker proteins. Conclusions: Interaction of COX-2 and ER stress regulates apoptosis and contributes to Myocardial lesion induced by I/R.