Objective To explore the role and mechanism of peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) in remifentanil (REM) resistance to hepatic ischemia-reperfusion injury (HIRI). Methods Forty SD rats were randomly divided into sham surgery group, HIRI group, HIRI+REM group, HIRI+PGC-1α inhibitor SR-18292 (HIRI+SR-18292) group and HIRI+REM+SR-18292 group, 8 rats in each group. HIRI rat models were constructed using non-invasive arterial clip occlusion method, and REM or SR-18292 were intravenously injected before surgery. The liver function indicators and liver tissue adenosine triphosphate (ATP) levels in the serum of rats were detected by assay kits. The activity levels of mitochondrial respiratory chain complexes Ⅲ and Ⅳ (COX-Ⅲ, COX-Ⅳ) in rat liver tissue were assessed by colorimetric methods. The pathological changes in rat liver tissue were observed by hematoxylin-eosin staining. Reactive oxygen species (ROS) and oxidative stress-related indicators in rat liver tissue were measured using the fluorescent probe (DCFH-DA) method and colorimetric methods. The mitochondrial DNA (mtDNA) copies and the expression levels of PGC-1α, nuclear respiratory factor-1 (NRF-1) and mitochondrial transcription factor A (TFAM) messenger RNA (mRNA) in rat liver tissue were quantified by real-time fluorescent quantitative polymerase chain reaction (RT-qPCR). And the protein expression levels of PGC-1α, NRF-1 and TFAM in rat liver tissue were assessed by Western blotting. Results Compared with the sham group, rats in the HIRI group showed increased pathological scores and hepatic cell necrosis in liver tissue, elevated levels of alanine aminotransferase (ALT) and aspartate aminotransferase (AST) in serum, and increased levels of ROS and malondialdehyde (MDA) in liver tissue. Additionally, there was a decrease in ATP content and the activity levels of superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), COX-Ⅲ and COX-Ⅳ in liver tissue, as well as a decrease in mtDNA copies and the expression levels of PGC-1α, NRF-1 and TFAM mRNA and protein (all P<0.05). Compared with the HIRI group, rats in the HIRI+REM group exhibited decreased pathological scores and hepatic cell necrosis, reduced levels of serum ALT and AST, and decreased levels of ROS and MDA in liver tissue. There was also an increase in ATP content and the activity levels of SOD, GSH-Px, COX-Ⅲ and COX-Ⅳ in liver tissue, as well as an increase in mtDNA copies and the expression levels of PGC-1α, NRF-1 and TFAM mRNA and protein (all P<0.05). In contrast, rats in the HIRI+SR-18292 group showed increased pathological scores and hepatic cell necrosis, elevated levels of serum ALT and AST, and increased levels of ROS and MDA in liver tissue. There was a decrease in ATP content and the activity levels of SOD, GSH-Px, COX-Ⅲ and COX-Ⅳ in liver tissue, as well as a decrease in mtDNA copies and the expression levels of PGC-1α, NRF-1 and TFAM mRNA and protein (all P<0.05). Compared with the HIRI+REM group, rats in the HIRI+REM+SR-18292 group had increased pathological scores and hepatic cell necrosis, elevated levels of serum ALT and AST, and increased levels of ROS and MDA in liver tissue. There was a decrease in ATP content and the activity levels of SOD, GSH-Px, COX-Ⅲ and COX-Ⅳ in liver tissue, as well as a decrease in mtDNA copies and the expression levels of PGC-1α, NRF-1 and TFAM mRNA and protein (all P<0.05). Conclusions PGC-1α plays a role in regulating the process of REM resistance to HIRI by promoting mitochondrial biogenesis and reducing the levels of oxidative stress.

[This corrects the article DOI: 10.1016/j.jpha.2023.08.006.].

Objective : To investigate the mechanisms of bromodomain-containing protein 4(BRD4) in TGF-β1-induced epithelial-mesenchymal transition in alveolar type II epithelial cells. Methods : MLE-12 cells were stimulated with different concentrations(5 ng/ml, 10 ng/ml) of TGF-β1 for 48 h to establish an EMT cell model. The cells were pretreated with 50 nmol/L BRD4 inhibitor JQ-1, 100 μmol/L high mobility group box 1 protein(HMGB1)inhibitor glycyrrhizin acid(GA), and 3 μg/ml rHMGB1. The experimental groups were divided as follows: control group, TGF-β1 group, JQ-1 group, JQ-1+TGF-β1 group, GA group, GA+TGF-β1 group, and JQ-1+TGF-β1+rHMGB1 group. The effect of JQ-1 on cell viability was examined using cell counting kit-8(CCK-8). The protein expression levels of CDH1, ZO-1, Vimentin, α-SMA, BRD4, HMGB1, TGF-β1, Smad2/3 and p-Smad2/3 were detected by Western blot. The cell migration ability was detected by a scratch test. Results : Compared with the control group, the levels of Vimentin and α-SMA in the TGF-β1 group increased, and the levels of CDH1 and ZO-1 protein decreased, suggesting that the EMT model was successfully established. In this model, the expression of BRD4 and HMGB1 significantly increased. Different concentrations of JQ-1 could inhibit the cell viability of MLE-12 in a concentration-dependent manner. Both JQ-1 and GA could effectively alleviate TGF-β1-induced EMT, and reduce the increase in HMGB1 expression and the activation of TGF-β1/Smad2/3 pathway caused by TGF-β1. Moreover, rHMGB1 treatment could reduce the effects of JQ-1 on EMT and the TGF-β1/Smad2/3 pathway. Additionally, both JQ-1 and glycyrrhizin could effectively decrease TGF-β1-induced cell migration, whereas rHMGB1 could alleviate the inhibitory effect of JQ-1 on the rate of cell migration. Conclusion BRD4 can regulate epithelial-mesenchymal transition in alveolar type II epithelial cells via HMGB1/TGF-β1/Smad2/3 signaling cascade, and BRD4 may be a potential target for inhibition of pulmonary fibrosis.

A major impedance to neuronal regeneration after peripheral nerve injury(PNI)is the activation of various programmed cell death mechanisms in the dorsal root ganglion.Ferroptosis is a form of pro-grammed cell death distinguished by imbalance in iron and thiol metabolism,leading to lethal lipid peroxidation.However,the molecular mechanisms of ferroptosis in the context of PNI and nerve regeneration remain unclear.Ferroportin(Fpn),the only known mammalian nonheme iron export protein,plays a pivotal part in inhibiting ferroptosis by maintaining intracellular iron homeostasis.Here,we explored in vitro and in vivo the involvement of Fpn in neuronal ferroptosis.We first delineated that reactive oxygen species at the injury site induces neuronal ferroptosis by increasing intracellular iron via accelerated UBA52-driven ubiquitination and degradation of Fpn,and stimulation of lipid peroxidation.Early administration of the potent arterial vasodilator,hydralazine(HYD),decreases the ubiquitination of Fpn after PNI by binding to UBA52,leading to suppression of neuronal cell death and significant ac-celeration of axon regeneration and motor function recovery.HYD targeting of ferroptosis is a promising strategy for clinical management of PNI.

Objective:To explore the prospective associations between physical activity and incident ischemic stroke in adults.Methods:Data of China Kadoorie Biobank study in Tongxiang of Zhejiang were used. After excluding participants with cancers, strokes, heart diseases and diabetes at baseline study, a total of 53 916 participants aged 30-79 years were included in the final analysis. The participants were divided into 5 groups according to the quintiles of their physical activity level. Cox proportional hazard regression models was used to calculate the hazard ratios ( HR) for the analysis on the association between baseline physical activity level and risk for ischemic stroke. Results:The total physical activity level in the participants was (30.63±15.25) metabolic equivalent (MET)-h/d, and it was higher in men [(31.04±15.48) MET-h/d] than that in women [(30.33±15.07) MET-h/d] ( P<0.001). In 595 526 person-years of the follow-up (average 11.4 years), a total of 1 138 men and 1 082 women were newly diagnosed with ischemic stroke. Compared to participants with the lowest physical activity level (<16.17 MET-h/d), after adjusting for socio-demographic factors, lifestyle, BMI, waist circumference, and SBP, the HRs for the risk for ischemic stroke in those with moderate low physical activity level (16.17-24.94 MET-h/d), moderate physical activity level (24.95-35.63 MET-h/d), moderate high physical activity level (35.64-43.86 MET-h/d) and the highest physical activity level (≥43.87 MET-h/d) were 0.93 (95% CI: 0.83-1.04), 0.87 (95% CI: 0.76-0.98), 0.82 (95% CI: 0.71-0.95) and 0.76 (95% CI: 0.64-0.89), respectively. Conclusion:Improving physical activity level has an effect on reducing the risk for ischemic stroke.

Background Silicosis is an occupational disease mainly characterized by pulmonary progressive fibrosis induced by the accumulation of free silica (SiO₂) in the lungs due to long-term exposure to SiO₂ dust. It has been shown that neutrophil extracellular traps (NETs) are increased in the lung tissues of silicotic mice after 28 d SiO₂ exposure, but it is unclear how the levels of NETs change throughout entire progression of silicosis in mice. Objective To observe the levels of NETs and pathological changes in the lungs of silicotic mice after different duration of SiO₂ exposure, and to confirm the possible role and significance of NETsin the development of SiO₂-induced pulmonary fibrosis. Methods A total of 28 SPF male C57BL/6J mice were randomly divided into a control group, and a model group, and the model group was subdivided into, a 2 d model group, a 7 d model group, and a 28 d model group, with 7 mice in each group. The mice in the model groups were given intratracheal instillation with 10 mg SiO₂ suspension (50 μL), and the mice in the control group were received same volume of saline. Mice were sacrificed and samples were collected at designed time points. The pathological changes of lung tissues of mice were observed after hematoxylin-eosin (HE) and Van Gieson (VG) staining. Immunofluorescence was used to observe the NETs markers citrullination histone H3 (CitH3) and myeloperoxidase (MPO) in bronchoalveolar lavage fluid (BALF), and the percentage of NETs-positive cells was calculated. PicoGreen fluorescent dye kit was used to detect the content of extracelluar DNA (ex-DNA) in mouse BALF, and the expression levels of fibrosis-related proteins α-smooth muscle actin (α-SMA) and fibronectin (FN) and NETs marker CitH3 in lung tissues of mice were detected by Western blot (WB). Results Compared with the control group, inflammatory cells accumulation, alveolar wall thickening, and collagen deposition were obviously observed in the lungs of the silicosis model groups, and a large number of silicone nodules were recorded in the lung tissues in the 28 d group. Compared with the control group, the expressions of α-SMA and FN in the lung tissue of the 28 d group were significantly increased (P<0.05). The percentages of NETs in BALF increased significantly in the 2 d and the 7 d model group, then decreased in the 28 d model group (P<0.05). Compared with the control group (7.434±0.258) ng·mL⁻¹, the ex-DNA levels in BALF of mice in the 2 d [(35.110±6.331) ng·mL⁻¹], the 7 d [(39.491±6.948) ng·mL⁻¹], and the 28 d [(23.360±4.809) ng·mL⁻¹] model groups were increased (P<0.05), and the increase of ex-DNA in the 2 d and the 7 d model groups were statistically significant (P<0.05). In comparison with the control group, the protein level of CitH3 was significantly increased in the lung tissues of mice in the 7 d model group (P<0.05). Conclusion The content of NETs increases significantly and reaches a peak in the early inflammatory stage of silicosis, and decreases as the disease progresses to the fibrotic stage, suggesting that NETs may play a role in early stage of silicosis.

Diabetic kidney disease(DKD)is the main microvascular complication of diabetes mellitus and a common cause of end stage renal disease.Ferroptosis is involved in the pathogenesis of DKD,therefore drugs targeting iron death may affect the progression of DKD.This article reviews the research progress of inhibiting ferroptosis in the treatment of DKD.

Diabetic kidney disease(DKD)is not only the main microvascular complication of diabetes mellitus,but also a common cause of end stage renal disease.Oxidative stress and nuclear factor E2-related factor 2(Nrf2)/kelch like epichlorohydrin related protein 1/antioxidant response element pathway damage may be involved in the occurrence and development of DKD.This article reviews the research progress of targeted activation of Nrf2 pathway and DKD treatment.

Objective : To explore the regulatory role of microRNA⁃455 ⁃3p ( miR⁃455 ⁃3p) in lymphangiogenesis of rat silicosis model , and to investigate the effect of miR⁃455 ⁃3p targeted regulation of vascular endothelial growth factor C (VEGF⁃C) on the tubular structure formation of human lymphatic endothelial cells ( HLECs) . Methods: The rats were randomly divided into the silicosis model group and the normal control group. The silicosis model group were injected with silicon dioxide (SiO2 )dust suspension , and the control group was injected with the same amount of normal saline. HE , Masson and immunohistochemistry staining were used to observe the pathological changes and lymphangiogenesis of lung tissue. The expression levels of miR⁃455 ⁃3p and VEGF⁃C in lung tissues of rats were detected by Quantitative real⁃time PCR ( RT⁃qPCR) and Western blot; The miR⁃455 ⁃3p inhibitors and negative controls ( NC) were transfected into HLECs , and the expression levels of miR⁃455 ⁃3p and VEGF⁃C in cells were detected by RT⁃qPCR and Western blot. The migration ability of HLECs was detected by scratch test , the ability of tubular structure formation was detected by matrigel tube formation test , and dual luciferase experiments were used to verify the targeting relationship between miR⁃455 ⁃3p and VEGF⁃C. Results : Compared with the normal control group , in the silicosis model group , a large number of inflammatory cells gathered and collagen gradually deposited in the pulmonary interstitium , and there was lymphatic hyperplasia in the lung. The expression of miR⁃455 ⁃3p in the lung tissue was lower than that in the control group , and the expression of VEGF⁃C was higher than that in the control group ; After transfection with HLECs , compared with the NC group , the expression of miR⁃455 ⁃3p in the cells of the Inhibitors group decreased , the expression of VEGF⁃C increased , and the ability of cell migration and tubular structure formation increased(P < 0. 05) ; VEGF⁃C was confirmed as a target gene of miR⁃455 ⁃3p by the dual luciferase experiments. Conclusion miR⁃455 ⁃3p can affect the tubular structure formation ability of HLECs and regulate lymphangiogenesis by targeting the expression of VEGF⁃C.

Objective:To observe the occurrence of epithelial-mesenchymal transition (EMT) in cervical cancer cell line Siha irradiated by X-rays with clinical conventional fraction radiotherapy model and investigate the role of exosomes in this process.Methods:Siha cells were irradiated by 6 MV-X rays with 50 Gy in 25 fractions. EMT was evaluated by cell morphology, EMT biomarkers and cell migration and invasion ability. Exosomes released from cells were detected by transmission electron microscopy and nanoparticle tracking analysis (NTA), and its function in EMT was explored by using an exosome inhibitor GW4869 (10 μmol/L).Results:After irradiation, EMT phenomenon was induced in the survived Siha cells, including the incidence of mesenchymal phenotype, upregulation of epithelial marker E-cadherin ( t=9.66, P<0.05), downregulation of mesenchymal marker N-cadherin ( t=41.61, P<0.05), and increase of cell migration and invasion abilities ( t=6.11, 13.22; P<0.05). Meanwhile, the secretion of exosomes was also increased after irradiation ( t=7.51, P<0.05). When the cells were pre-treated with GW4869, radiation-induced exosome secretion was reduced ( t=7.28, P<0.05), so that radiation-induced EMT was reversed. Conclusions:Ionizing radiation with clinical conventional fraction radiotherapy model promotes EMT of cervical cancer cells through increasing the secretion of exosomes.