1.Inhibition of interferon regulatory factor 4 orchestrates T cell dysfunction, extending mouse cardiac allograft survival.
Wenjia YUAN ; Hedong ZHANG ; Longkai PENG ; Chao CHEN ; Chen FENG ; Zhouqi TANG ; Pengcheng CUI ; Yaguang LI ; Tengfang LI ; Xia QIU ; Yan CUI ; Yinqi ZENG ; Jiadi LUO ; Xubiao XIE ; Yong GUO ; Xin JIANG ; Helong DAI
Chinese Medical Journal 2025;138(10):1202-1212
BACKGROUND:
T cell dysfunction, which includes exhaustion, anergy, and senescence, is a distinct T cell differentiation state that occurs after antigen exposure. Although T cell dysfunction has been a cornerstone of cancer immunotherapy, its potential in transplant research, while not yet as extensively explored, is attracting growing interest. Interferon regulatory factor 4 (IRF4) has been shown to play a pivotal role in inducing T cell dysfunction.
METHODS:
A novel ultra-low-dose combination of Trametinib and Rapamycin, targeting IRF4 inhibition, was employed to investigate T cell proliferation, apoptosis, cytokine secretion, expression of T-cell dysfunction-associated molecules, effects of mitogen-activated protein kinase (MAPK) and mammalian target of rapamycin (mTOR) signaling pathways, and allograft survival in both in vitro and BALB/c to C57BL/6 mouse cardiac transplantation models.
RESULTS:
In vitro , blockade of IRF4 in T cells effectively inhibited T cell proliferation, increased apoptosis, and significantly upregulated the expression of programmed cell death protein 1 (PD-1), Helios, CD160, and cytotoxic T lymphocyte-associated antigen (CTLA-4), markers of T cell dysfunction. Furthermore, it suppressed the secretion of pro-inflammatory cytokines interferon (IFN)-γ and interleukin (IL)-17. Combining ultra-low-dose Trametinib (0.1 mg·kg -1 ·day -1 ) and Rapamycin (0.1 mg·kg -1 ·day -1 ) demonstrably extended graft survival, with 4 out of 5 mice exceeding 100 days post-transplantation. Moreover, analysis of grafts at day 7 confirmed sustained IFN regulatory factor 4 (IRF4) inhibition, enhanced PD-1 expression, and suppressed IFN-γ secretion, reinforcing the in vivo efficacy of this IRF4-targeting approach. The combination of Trametinib and Rapamycin synergistically inhibited the MAPK and mTOR signaling network, leading to a more pronounced suppression of IRF4 expression.
CONCLUSIONS
Targeting IRF4, a key regulator of T cell dysfunction, presents a promising avenue for inducing transplant immune tolerance. In this study, we demonstrate that a novel ultra-low-dose combination of Trametinib and Rapamycin synergistically suppresses the MAPK and mTOR signaling network, leading to profound IRF4 inhibition, promoting allograft acceptance, and offering a potential new therapeutic strategy for improved transplant outcomes. However, further research is necessary to elucidate the underlying pharmacological mechanisms and facilitate translation to clinical practice.
Animals
;
Mice
;
Mice, Inbred BALB C
;
Mice, Inbred C57BL
;
Interferon Regulatory Factors/metabolism*
;
Heart Transplantation/methods*
;
T-Lymphocytes/immunology*
;
Sirolimus/therapeutic use*
;
Pyridones/therapeutic use*
;
Graft Survival/drug effects*
;
Pyrimidinones/therapeutic use*
;
Cell Proliferation/drug effects*
;
Apoptosis/drug effects*
;
Male
;
Signal Transduction/drug effects*
2.Feixin Decoction Treats Hypoxic Pulmonary Hypertension by Regulating Pyroptosis in PASMCs via PPARγ/NF-κB/NLRP3 Signaling Pathway
Junlan TAN ; Xianya CAO ; Runxiu ZHENG ; Wen ZHANG ; Chao ZHANG ; Jian YI ; Feiying WANG ; Xia LI ; Jianmin FAN ; Hui LIU ; Lan SONG ; Aiguo DAI
Chinese Journal of Experimental Traditional Medical Formulae 2025;31(18):1-9
ObjectiveTo investigate the mechanism by which Feixin decoction treats hypoxic pulmonary hypertension (HPH) by regulating the peroxisome proliferator-activated receptor gamma (PPARγ)/nuclear factor-kappa B (NF-κB)/NOD-like receptor pyrin domain containing 3 (NLRP3) signaling pathway. MethodsForty-eight male SD rats were randomly allocated into normal, hypoxia, and low-, medium- and high-dose (5.85, 11.7, 23.4 g·kg-1, respectively) Feixin decoction groups, with 8 rats in each group. Except the normal group, the remaining five groups were placed in a hypoxia chamber with an oxygen concentration of (10.0±0.5)% for 8 h per day, 28 days, and administrated with corresponding drugs during the modeling process. After 4 weeks of treatment, echocardiographic parameters [pulmonary artery acceleration time (PAT), pulmonary artery ejection time (PET), right ventricular anterior wall thickness (RVAWd), and tricuspid annular plane systolic excursion (TAPSE)] were measured for each group. The right ventricular systolic pressure (RVSP) was measured by the right heart catheterization method, and the right ventricular hypertrophy index (RVHI) was calculated by weighing the heart. The pathological changes in pulmonary arterioles were observed by hematoxylin-eosin staining. The co-localization of α-smooth muscle actin (α-SMA) with NLRP3, N-terminal gasdermin D (N-GSDMD), and cysteinyl aspartate-specific proteinase-1 (Caspase-1) in pulmonary arteries was detected by immunofluorescence. The protein levels of PPARγ, NF-κB, NLRP3, apoptosis-associated speck-like protein containing a CARD (ASC), N-GSDMD, interleukin-1β (IL-1β), interleukin-18(IL-18), and cleaved Caspase-1 in the lung tissue was determined by Western blot. The ultrastructural changes in pulmonary artery smooth muscle cells (PASMCs) were observed by transmission electron microscopy. ResultsCompared with the normal group, the hypoxia group showed increased RVSP and RVHI (P<0.01), decreased right heart function (P<0.01), increased pulmonary vascular remodeling (P<0.01), increased co-localization of α-SMA with NLRP3, N-GSDMD, and Caspase-1 in pulmonary arterioles (P<0.01), up-regulated protein levels of NF-κB, NLRP3, ASC, N-GSDMD, IL-1β, IL-18, and cleaved Caspase-1 in the lung tissue (P<0.05, P<0.01), a down-regulated protein level of PPARγ (P<0.05, P<0.01), and pyroptosis in PASMCs. Compared with the hypoxia group, Feixin decoction reduced RVSP and RVHI, improved the right heart function and ameliorated pulmonary vascular remodeling (P<0.05, P<0.01), decreased the co-localization of α-SMA with NLRP3, N-GSDMD, and Caspase-1 (P<0.05, P<0.01), down-regulated the protein levels of NF-κB, NLRP3, ASC, N-GSDMD, IL-1β, IL-18, and cleaved Caspase-1 in the lung tissue (P<0.05, P<0.01), up-regulated the protein level of PPARγ (P<0.05, P<0.01), and alleviated pyroptosis in PASMCs. ConclusionFeixin decoction can ameliorate pulmonary vascular remodeling and right heart dysfunction in chronically induced HPH rats by regulating pyroptosis in PASMCs through the PPARγ/NF-κB/NLRP3 pathway.
3.Intestinal metabolites in colitis-associated carcinogenesis: Building a bridge between host and microbiome.
Yating FAN ; Yang LI ; Xiangshuai GU ; Na CHEN ; Ye CHEN ; Chao FANG ; Ziqiang WANG ; Yuan YIN ; Hongxin DENG ; Lei DAI
Chinese Medical Journal 2025;138(16):1961-1972
Microbial-derived metabolites are important mediators of host-microbial interactions. In recent years, the role of intestinal microbial metabolites in colorectal cancer has attracted considerable attention. These metabolites, which can be derived from bacterial metabolism of dietary substrates, modification of host molecules such as bile acids, or directly from bacteria, strongly influence the progression of colitis-associated cancer (CAC) by regulating inflammation and immune response. Here, we review how microbiome metabolites short-chain fatty acids (SCFAs), secondary bile acids, polyamines, microbial tryptophan metabolites, and polyphenols are involved in the tumorigenesis and development of CAC through inflammation and immunity. Given the heated debate on the metabolites of microbiota in maintaining gut homeostasis, serving as tumor molecular markers, and affecting the efficacy of immune checkpoint inhibitors in recent years, strategies for the prevention and treatment of CAC by targeting intestinal microbial metabolites are also discussed in this review.
Humans
;
Gastrointestinal Microbiome/physiology*
;
Animals
;
Carcinogenesis/metabolism*
;
Colitis-Associated Neoplasms/microbiology*
;
Fatty Acids, Volatile/metabolism*
;
Bile Acids and Salts/metabolism*
;
Colitis/microbiology*
4.Circadian and non-circadian regulation of the male reproductive system and reproductive damage: advances in the role and mechanisms of clock genes.
Meng-Chao HE ; Ying-Zhong DAI ; Yi-Meng WANG ; Qin-Ru LI ; Si-Wen LUO ; Xi LING ; Tong WANG ; Jia CAO ; Qing CHEN
Acta Physiologica Sinica 2025;77(4):712-720
Recently, male reproductive health has attracted extensive attention, with the adverse effects of circadian disruption on male fertility gradually gaining recognition. However, the mechanism by which circadian disruption leads to damage to male reproductive system remains unclear. In this review, we first summarized the dual regulatory roles of circadian clock genes on the male reproductive system: (1) circadian regulation of testosterone synthesis via the hypothalamic-pituitary-testicular (HPT) and hypothalamic-pituitary-adrenal (HPA) axes; (2) non-circadian regulation of spermatogenesis. Next, we further listed the possible mechanisms by which circadian disruption impairs male fertility, including interference with the oscillatory function of the reproductive system, i.e., synchronization of the HPT axis, crosstalk between the HPT axis and the HPA axis, as well as direct damage to germ cells by disturbing the non-oscillatory function of the reproductive system. Future research using spatiotemporal omics, epigenomic assays, and neural circuit mapping in studying the male reproductive system may provide new clues to systematically unravel the mechanisms by which circadian disruption affects male reproductive system through circadian clock genes.
Male
;
Humans
;
Animals
;
Circadian Clocks/physiology*
;
Hypothalamo-Hypophyseal System/physiology*
;
Circadian Rhythm/genetics*
;
Spermatogenesis/physiology*
;
Pituitary-Adrenal System/physiology*
;
Testis/physiology*
;
Testosterone/biosynthesis*
;
CLOCK Proteins
;
Infertility, Male/physiopathology*
5.A cephalometric landmark detection method using dual-encoder on X-ray image.
Chao DAI ; Chaolin HUANG ; Minpeng XU ; Yang WANG
Journal of Biomedical Engineering 2025;42(5):883-891
Accurate detection of cephalometric landmarks is crucial for orthodontic diagnosis and treatment planning. Current landmark detection methods are mainly divided into heatmap-based and regression-based approaches. However, these methods often rely on parallel computation of multiple models to improve accuracy, significantly increasing the complexity of training and deployment. This paper presented a novel regression method that can simultaneously detect all cephalometric landmarks in high-resolution X-ray images. By leveraging the encoder module of Transformer, a dual-encoder model was designed to achieve coarse-to-fine localization of cephalometric landmarks. The entire model consisted of three main components: a feature extraction module, a reference encoder module, and a fine-tuning encoder module, responsible for feature extraction and fusion of X-ray images, coarse localization of cephalometric landmarks, and fine localization of landmarks, respectively. The model was fully end-to-end differentiable and could learn the intercorrelation relationships between cephalometric landmarks. Experimental results showed that the successful detection rate (SDR) of our algorithm was superior to other existing methods. It attained the highest 2 mm SDR of 89.51% on test set 1 of the ISBI2015 dataset and 90.68% on the test set of the ISBI2023 dataset. Meanwhile, it reduces memory consumption and enhances the model's popularity and applicability, providing more reliable technical support for orthodontic diagnosis and treatment plan formulation.
Cephalometry/methods*
;
Humans
;
Algorithms
;
Anatomic Landmarks/diagnostic imaging*
;
Image Processing, Computer-Assisted/methods*
;
X-Rays
6.Dimethyloxalylglycine improves functional recovery through inhibiting cell apoptosis and enhancing blood-spinal cord barrier repair after spinal cord injury.
Wen HAN ; Chao-Chao DING ; Jie WEI ; Dan-Dan DAI ; Nan WANG ; Jian-Min REN ; Hai-Lin CHEN ; Ling XIE
Chinese Journal of Traumatology 2025;28(5):361-369
PURPOSE:
The secondary damage of spinal cord injury (SCI) starts from the collapse of the blood spinal cord barrier (BSCB) to chronic and devastating neurological deficits. Thereby, the retention of the integrity and permeability of BSCB is well-recognized as one of the major therapies to promote functional recovery after SCI. Previous studies have demonstrated that activation of hypoxia inducible factor-1α (HIF-1α) provides anti-apoptosis and neuroprotection in SCI. Endogenous HIF-1α, rapidly degraded by prolylhydroxylase, is insufficient for promoting functional recovery. Dimethyloxalylglycine (DMOG), a highly selective inhibitor of prolylhydroxylase, has been reported to have a positive effect on axon regeneration. However, the roles and underlying mechanisms of DMOG in BSCB restoration remain unclear. Herein, we aim to investigate pathological changes of BSCB restoration in rats with SCI treated by DOMG and evaluate the therapeutic effects of DMOG.
METHODS:
The work was performed from 2022 to 2023. In this study, Allen's impact model and human umbilical vein endothelial cells were employed to explore the mechanism of DMOG. In the phenotypic validation experiment, the rats were randomly divided into 3 groups: sham group, SCI group, and SCI + DMOG group (10 rats for each). Histological analysis via Nissl staining, Basso-Beattie-Bresnahan scale, and footprint analysis was used to evaluate the functional recovery after SCI. Western blotting, TUNEL assay, and immunofluorescence staining were employed to exhibit levels of tight junction and adhesion junction of BSCB, HIF-1α, cell apoptosis, and endoplasmic reticulum (ER) stress. The one-way ANOVA test was used for statistical analysis. The difference was considered statistically significant at p < 0.05.
RESULTS:
In this study, we observed the expression of HIF-1α reduced in the SCI model. DMOG treatment remarkably augmented HIF-1α level, alleviated endothelial cells apoptosis and disruption of BSCB, and enhanced functional recovery post-SCI. Besides, the administration of DMOG offset the activation of ER stress induced by SCI, but this phenomenon was blocked by tunicamycin (an ER stress activator). Finally, we disclosed that DMOG maintained the integrity and permeability of BSCB by inhibiting ER stress, and inhibition of HIF-1α erased the protection from DMOG.
CONCLUSIONS
Our findings illustrate that the administration of DMOG alleviates the devastation of BSCB and HIF-1α-induced inhibition of ER stress.
Spinal Cord Injuries/pathology*
;
Animals
;
Apoptosis/drug effects*
;
Amino Acids, Dicarboxylic/therapeutic use*
;
Recovery of Function/drug effects*
;
Rats
;
Rats, Sprague-Dawley
;
Hypoxia-Inducible Factor 1, alpha Subunit/metabolism*
;
Male
;
Spinal Cord/blood supply*
7.Clinical characteristics and outcomes of 11 neonates with venous thrombosis.
Xi-Ge GU ; Li-Ying DAI ; Xiao-Qing SHI ; Wen-Chao ZHANG ; Yong-Li ZHANG
Chinese Journal of Contemporary Pediatrics 2025;27(5):588-594
OBJECTIVES:
To summarize the clinical characteristics, diagnosis, and treatment outcomes of neonatal venous thrombosis.
METHODS:
A retrospective analysis was conducted on the clinical data of 11 neonates with venous thrombosis admitted to the Department of Neonatology of Anhui Children's Hospital from January 2019 to September 2024. The clinical characteristics, diagnostic approaches, treatments, and outcomes were analyzed.
RESULTS:
Among the 11 neonates diagnosed with venous thrombosis, 5 were male, and 6 were preterm infants, with a median gestational age of 35+6 weeks, birth weight of (2 322±1 069) g, and admission temperature of (36.6±0.4)°C. The median age at symptom onset was 6 days. Of the 11 cases, 8 limb venous thromboses and 1 portal vein thrombosis were confirmed by vascular ultrasound, and 2 cases of intracranial venous sinus thrombosis were confirmed by magnetic resonance imaging. Ten cases received low molecular weight heparin for anticoagulation, with a treatment duration of (24±15) days; 2 cases were treated with urokinase thrombolysis, and 4 cases received fresh frozen plasma transfusion. Thrombosis resolved in 7 cases before discharge. Partial resolution occurred in 2 cases before discharge (1 continued outpatient treatment until resolution and 1 resolved during follow-up). One case was transferred to another hospital after 1 day of treatment and was discharged after thrombosis reduction. No adverse reactions such as bleeding were observed. One neonate with cerebral infarction at admission did not receive heparin anticoagulation and was followed up as an outpatient.
CONCLUSIONS
Vascular ultrasound is the most commonly used diagnostic method for neonatal venous thrombosis. Heparin anticoagulation is the recommended treatment. The overall prognosis of neonatal venous thrombosis is favorable.
Humans
;
Male
;
Venous Thrombosis/drug therapy*
;
Infant, Newborn
;
Female
;
Retrospective Studies
8.A Study of Flow Sorting Lymphocyte Subsets to Detect Epstein-Barr Virus Reactivation in Patients with Hematological Malignancies.
Hui-Ying LI ; Shen-Hao LIU ; Fang-Tong LIU ; Kai-Wen TAN ; Zi-Hao WANG ; Han-Yu CAO ; Si-Man HUANG ; Chao-Ling WAN ; Hai-Ping DAI ; Sheng-Li XUE ; Lian BAI
Journal of Experimental Hematology 2025;33(5):1468-1475
OBJECTIVE:
To analyze the Epstein-Barr virus (EBV) load in different lymphocyte subsets, as well as clinical characteristics and outcomes in patients with hematologic malignancies experiencing EBV reactivation.
METHODS:
Peripheral blood samples from patients were collected. B, T, and NK cells were isolated sorting with magnetic beads by flow cytometry. The EBV load in each subset was quantitated by real-time quantitative polymerase chain reaction (RT-qPCR). Clinical data were colleted from electronic medical records. Survival status was followed up through outpatient visits and telephone calls. Statistical analyses were performed using SPSS 25.0.
RESULTS:
A total of 39 patients with hematologic malignancies were included, among whom 35 patients had undergone allogeneic hematopoietic stem cell transplantation (allo-HSCT). The median time to EBV reactivation was 4.8 months (range: 1.7-57.1 months) after allo-HSCT. EBV was detected in B, T, and NK cells in 20 patients, in B and T cells in 11 patients, and only in B cells in 4 patients. In the 35 patients, the median EBV load in B cells was 2.19×104 copies/ml, significantly higher than that in T cells (4.00×103 copies/ml, P <0.01) and NK cells (2.85×102 copies/ml, P <0.01). Rituximab (RTX) was administered for 32 patients, resulting in EBV negativity in 32 patients with a median time of 8 days (range: 2-39 days). Post-treatment analysis of 13 patients showed EBV were all negative in B, T, and NK cells. In the four non-transplant patients, the median time to EBV reactivation was 35 days (range: 1-328 days) after diagnosis of the primary disease. EBV was detected in one or two subsets of B, T, or NK cells, but not simultaneously in all three subsets. These patients received a combination chemotherapy targeting at the primary disease, with 3 patients achieving EBV negativity, and the median time to be negative was 40 days (range: 13-75 days).
CONCLUSION
In hematologic malignancy patients after allo-HSCT, EBV reactivation commonly involves B, T, and NK cells, with a significantly higher viral load in B cells compared to T and NK cells. Rituximab is effective for EBV clearance. In non-transplant patients, EBV reactivation is restricted to one or two lymphocyte subsets, and clearance is slower, highlighting the need for prompt anti-tumor therapy.
Humans
;
Hematologic Neoplasms/virology*
;
Herpesvirus 4, Human/physiology*
;
Epstein-Barr Virus Infections
;
Hematopoietic Stem Cell Transplantation
;
Virus Activation
;
Lymphocyte Subsets/virology*
;
Flow Cytometry
;
Killer Cells, Natural/virology*
;
Male
;
Female
;
B-Lymphocytes/virology*
;
Viral Load
;
Adult
;
T-Lymphocytes/virology*
;
Middle Aged
9.A clinical study of electrocochleography monitoring for residual hearing retention during minimally invasive cochlear implant.
Ruijie WANG ; Jianfen LUO ; Qinglei DAI ; Xiuhua CHAO ; Yifei NI ; Fangxia HU ; Yueran CAO ; Haibo WANG ; Xiaohui ZHOU ; Lei XU
Journal of Clinical Otorhinolaryngology Head and Neck Surgery 2025;39(5):425-432
Objective:To investigate the application value of intraoperative electrocochleography(ECochG) monitoring technique and insertion techniques in cochlear implant(CI) and analyze its relationship with postoperative residual hearing(RH) preservation. Methods:Thirty-one patients(35 ears) who received CI in our hospital from June 2022 to July 2024 were enrolled. The Advanced Bionics Active Insertion Monitoring(AIM) system was used for real-time ECochG monitoring during surgery. Intraoperative cochlear microphonics (CM) waveform changes were recorded and analyzed in relation to postoperative RH preservation. Results:①ECochG recordings were successfully obtained in 34 of 35 ears (97.1%). ②According to Harris classification, there were 7 ears(20.6%) of Type A(rising), 7 ears(20.6%) of Type C(declining), 8 ears(23.5%) of Type CC(fluctuating), and 12 ears(35.3%) of Type D(no response). ③The total CM amplitude decrease was significantly moderately correlated with postoperative low-mid frequency hearing loss(r=0.67, P=0.017). The total CM amplitude decrease was significantly moderately correlated with postoperative low frequency hearing loss(r=0.65, P=0.023). ④For the mean amplitude variation, the Amax was 30.70 μV, the Amin was 8.64 μV, and the Aend was 18.27 μV. ⑤Sixteen cases completed postoperative follow-up, with an average low-mid frequency(125-1 000 Hz) residual hearing loss of 15.25 dB HL and a RH preservation rate of 87.5%. Conclusion:Intraoperative ECochG monitoring can effectively predict postoperative residual hearing changes, effectively guide surgical manipulation, and improve residual hearing preservation rate.
Humans
;
Cochlear Implantation/methods*
;
Audiometry, Evoked Response
;
Cochlear Implants
;
Male
;
Female
;
Adult
;
Middle Aged
;
Monitoring, Intraoperative
;
Adolescent
;
Young Adult
;
Minimally Invasive Surgical Procedures
;
Child
;
Aged
;
Postoperative Period
10.G protein-coupled estrogen receptor alleviates lung injury in mice with exertional heat stroke by inhibiting ferroptosis.
Ziwei HAN ; Jiansong GUO ; Xiaochen WANG ; Zhi DAI ; Chao LIU ; Feihu ZHOU
Chinese Critical Care Medicine 2025;37(3):268-274
OBJECTIVE:
To investigate whether the G protein-coupled estrogen receptor (GPER) can attenuates acute lung injury in mice with exertional heat stroke (EHS) by inhibiting ferroptosis.
METHODS:
Sixty SPF-grade male C57BL/6 mice were randomly divided into four groups: normal control group (control group), EHS model group (EHS group), dimethyl sulfoxide (DMSO) solvent group (EHS+DMSO group), and GPER-specific agonist G1 group (EHS+G1 group), with 15 mice in each group. All mice underwent 14 days of adaptive training at 24-26 centigrade before modeling, and the EHS model was established using a high-temperature treadmill device. After successful modeling, the mice were allowed to cool naturally at room temperature. In the EHS+G1 group, 40 μg/kg of the GPER-specific agonist G1 was slowly injected intraperitoneally immediately after modeling. In the EHS+DMSO group, 40 μg/kg of DMSO was slowly injected intraperitoneally immediately after modeling. The control group received no treatment. Five hours after modeling, abdominal aortic blood was collected, and lung tissues were harvested after euthanasia. The lung coefficient was calculated to evaluate lung injury. Lung histopathological changes were observed under a light microscope after hematoxylin-eosin (HE) staining, and a lung histopathological score was assigned. Enzyme-linked immunosorbent assay (ELISA) was used to detect serum levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), malondialdehyde (MDA), and Fe2+ in lung tissue. Immunofluorescence was used to detect the expression of glutathione peroxidase 4 (GPX4). Real-time polymerase chain reaction (RT-PCR) was used to detect the mRNA expression of GPX4, ferroportin 1 (FPN1), and ferritin heavy chain 1 (FTH1). Western blotting was performed to detect the protein expression of GPX4, FPN1, and FTH1.
RESULTS:
Compared with the control group, the lung coefficient and lung histopathological score were significantly increased in the EHS group. HE staining showed significant thickening and unevenness of the alveolar septa and alveolar walls, partial alveolar collapse, and extensive erythrocyte, inflammatory cell, and plasma-like material extravasation in the alveolar spaces. Serum levels of TNF-α, IL-1β, MDA, and Fe2+ were significantly elevated. Immunofluorescence staining showed a significant decrease in GPX4-positive expression in lung tissue. Western blotting and RT-PCR showed significantly reduced protein and mRNA expression of GPX4, FPN1, and FTH1 in lung tissue. Compared with the EHS group, the EHS+G1 group showed a significant reduction in lung coefficient and lung histopathological score [lung coefficient (mg/g): 3.9±0.1 vs. 4.6±0.3, lung histopathological score: 4.2±0.2 vs. 6.9±0.2, both P < 0.05]. HE staining revealed reduced severity of lung tissue fluid extravasation, inflammatory infiltration, decreased hemorrhage, and less severe alveolar structural damage. Serum levels of TNF-α, IL-1β, MDA, and Fe2+ were significantly reduced [TNF-α (ng/L): 44.3±0.2 vs. 64.6±0.3, IL-1β (ng/L): 69.3±0.4 vs. 97.8±0.2, MDA (nmol/L): 2.8±0.3 vs. 3.6±0.5, Fe2+ (nmol/L): 0.021±0.004 vs. 0.028±0.004, all P < 0.05]. Immunofluorescence staining showed a significant decrease in GPX4-positive expression in lung tissue (fluorescence intensity: 35.53±2.41 vs. 16.45±0.31, P < 0.05). RT-PCR and Western blotting showed significantly increased mRNA and protein expression of GPX4, FPN1, and FTH1 in lung tissue [mRNA expression: GPX4 mRNA (2-ΔΔCt): 0.44±0.05 vs. 0.09±0.01, FPN1 mRNA (2-ΔΔCt): 0.77±0.17 vs. 0.42±0.14, FTH1 mRNA (2-ΔΔCt): 0.75±0.04 vs. 0.58±0.01; protein expression: GPX4/β-actin: 0.96±0.11 vs. 0.24±0.04, FPN1/β-actin: 1.26±0.21 vs. 0.44±0.14, FTH1/β-actin: 0.27±0.12 vs. 0.15±0.07; all P < 0.05]. However, there were no statistically significant differences in any of the above indicators between the EHS+DMSO group and the EHS group.
CONCLUSION
Activation of GPER can attenuate EHS-related lung injury in mice, and its mechanism may be related to the activation of the GPX4 signaling pathway and inhibition of ferroptosis.
Animals
;
Mice, Inbred C57BL
;
Male
;
Mice
;
Heat Stroke/metabolism*
;
Receptors, G-Protein-Coupled
;
Ferroptosis
;
Receptors, Estrogen
;
Acute Lung Injury/metabolism*
;
Tumor Necrosis Factor-alpha/metabolism*
;
Interleukin-1beta/metabolism*
;
Lung Injury
;
Lung/metabolism*

Result Analysis
Print
Save
E-mail