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Shi L, Liu Y, Wang J, Chang C, Zhu X, Wei L, Chen X, Zhang Z. Selenomethionine attenuates Klebsiella pneumoniae-induced jejunal injury in rabbits by inhibiting the TLR4/NF-κB pathway. Microb Pathog 2025; 203:107510. [PMID: 40147555 DOI: 10.1016/j.micpath.2025.107510] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Revised: 03/22/2025] [Accepted: 03/24/2025] [Indexed: 03/29/2025]
Abstract
Klebsiella pneumoniae (KP) infection often causes diarrhoea and intestinal barrier damage in young rabbits. The objective of this study was to explore whether selenomethionine (SeMet) can attenuate the jejunal injury caused by KP in rabbits. Therefore, we investigated the protective effect of SeMet by performing haematoxylin-eosin (HE), alcian blue periodic acid Schiff (AB-PAS), proliferating nuclear antigen (PCNA), TUNEL and immunofluorescence staining. In addition, the concentrations of Interleukin-1β (IL-1β), Interleukin-6 (IL-6), Tumor necrosisfactor-α (TNF-α) and Interleukin-10 (IL-10) in the jejunal tissue were detected by enzyme-linked immunosorbent assay (ELISA). The results showed that after KP infection, the productivity of rabbits decreased, and the mucosal barrier of the jejunum was damaged. Moreover, KP induced jejunal inflammation, activated the TLR4/NF-κB signalling pathway, and promoted the expression of the IL-1β, IL-6, and TNF-α. In addition, KP increased the apoptotic response of intestinal cells and upregulated the expression of caspase-3 and caspase-9. SeMet pretreatment significantly decreased the degree of intestinal epithelial cell apoptosis. Therefore, we showed that SeMet can reduce inflammation and enhance intestinal barrier function to improve the production performance of rabbits infected with KP.
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Affiliation(s)
- Lihui Shi
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China
| | - Yumei Liu
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China
| | - Jianing Wang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China
| | - Chenhao Chang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China
| | - Xuemin Zhu
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China
| | - Lan Wei
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China
| | - Xiaoguang Chen
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China
| | - Ziqiang Zhang
- College of Animal Science and Technology, Henan University of Science and Technology, Luoyang, China.
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Shi M, Liu K, Li X, Zeng XL, Liu XJ. Melatonin ameliorates PM2.5-induced airway inflammation and apoptosis by PERK/eIF2α/ATF4/CHOP in chronic obstructive pulmonary disease mice. Toxicol Appl Pharmacol 2025; 499:117314. [PMID: 40154578 DOI: 10.1016/j.taap.2025.117314] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2025] [Revised: 03/05/2025] [Accepted: 03/25/2025] [Indexed: 04/01/2025]
Abstract
Fine particulate matter (PM2.5) has been reported to exacerbate chronic airway inflammation, contributing to progression and acute exacerbation of chronic obstructive pulmonary disease (COPD). Persistent activated endoplasmic reticulum (ER) stress-related PERK/eIF2α/ATF4/CHOP pathway is critical in driving inflammation and cell death in a variety of inflammatory diseases. Melatonin (MEL) is well-recognized for its broad biological activities, such as anti-oxidative and anti-inflammatory effects However, the exact role of ER stress-related pathway and MEL in PM2.5-induced airway inflammation and apoptosis in COPD has not yet been elucidated. Therefore, we constructed the COPD mice model by cigarette smoke (CS) exposure to evaluate the mechanism by which PM2.5 exacerbate the development of COPD and the protective role of MEL. Results indicated that PM2.5 significantly impair lung function, disrupt emphysema, exacerbate inflammation and apoptosis and intensify the PERK/eIF2α/ATF4/CHOP pathway in COPD mice. Moreover, these changes caused by PM2.5 could be mitigated by MEL. In vitro, PM2.5 exposure notably reduced cell viability and triggered inflammation and apoptosis in BEAS-2B cells induced by cigarette smoke extract (CSE). These effects were reversed by the ER stress inhibitor 4-phenylbutyric acid (4-PBA), with MEL demonstrating similar effect. These findings demonstrate that PM2.5 aggravates airway inflammation and apoptosis via activating ER stress-related PERK/eIF2α/ATF4/CHOP pathways in COPD, which could be significantly restored by MEL.
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Affiliation(s)
- Meng Shi
- The First school of Clinical Medicine, Lanzhou University, Lanzhou 730000, China
| | - Kai Liu
- The First school of Clinical Medicine, Lanzhou University, Lanzhou 730000, China
| | - Xin Li
- The First school of Clinical Medicine, Lanzhou University, Lanzhou 730000, China
| | - Xiao-Li Zeng
- The First school of Clinical Medicine, Lanzhou University, Lanzhou 730000, China; The First Hospital of Lanzhou University, Lanzhou 730000, China
| | - Xiao-Ju Liu
- The First school of Clinical Medicine, Lanzhou University, Lanzhou 730000, China; The First Hospital of Lanzhou University, Lanzhou 730000, China.
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Ortiz-Placín C, Salido GM, González A. Melatonin Interplay in Physiology and Disease-The Fountain of Eternal Youth Revisited. Biomolecules 2025; 15:682. [PMID: 40427575 PMCID: PMC12109172 DOI: 10.3390/biom15050682] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2025] [Revised: 05/04/2025] [Accepted: 05/06/2025] [Indexed: 05/29/2025] Open
Abstract
Melatonin (N-acetyl-5-methoxytryptamine) is a hormone associated with the regulation of biological rhythms. The indoleamine is secreted by the pineal gland during the night, following a circadian rhythm. The highest plasmatic levels are reached during the night, whereas the lowest levels are achieved during the day. In addition to the pineal gland, other organs and tissues also produce melatonin, like, for example, the retina, Harderian glands, gut, ovaries, testes, skin, leukocytes, or bone marrow. The list of organs is extensive, including the cerebellum, airway epithelium, liver, kidney, adrenals, thymus, thyroid, pancreas, carotid body, placenta, and endometrium. At all these locations, the availability of melatonin is intended for local use. Interestingly, a decline of the circadian amplitude of the melatonin secretion occurs in old subjects in comparison to that found in younger subjects. Moreover, genetic and environmental factors are the primary causes of diseases, and oxidative stress is a key contributor to most pathologies. Numerous studies exist that show interesting effects of melatonin in different models of disease. Impairment in its secretion might have deleterious consequences for cellular physiology. In this regard, melatonin is a natural compound that is a carrier of a not yet completely known potential that deserves consideration. Thus, melatonin has emerged as a helpful ally that could be considered as a guard with powerful tools to orchestrate homeostasis in the body, majorly based on its antioxidant effects. In this review, we provide an overview of the widespread actions of melatonin against diseases preferentially affecting the elderly.
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Affiliation(s)
| | | | - Antonio González
- Institute of Molecular Pathology Biomarkers, University of Extremadura, Avenida de las Ciencias s/n, E-10003 Caceres, Spain; (C.O.-P.); (G.M.S.)
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Luo T, Chen W, Huang D, Liu X, Xi J, Fu Z, Chen J, Du Y, Cai R, Yu Q, Liu D, Du J, Liu L, Cai S, Dong H. Preclinical models of immune checkpoint inhibitors-related interstitial pneumonia for anti-PD1 tumor immunotherapy. Immunobiology 2025; 230:152884. [PMID: 39985972 DOI: 10.1016/j.imbio.2025.152884] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2024] [Revised: 02/11/2025] [Accepted: 02/13/2025] [Indexed: 02/24/2025]
Abstract
Immune-related adverse reactions (irAEs) are common adverse reactions after immune checkpoint inhibitor treatment, impacting the universality and continued use of immunotherapy. Currently, preclinical models to investigate the mechanisms underlying these adverse effects are inadequate. This study aims to develop both in vitro and in vivo models of irAEs to advance basic research on these adverse reactions. For vitro models, we designed two co-culture systems: "Lung epithelial cells-PBMC" conditional co-culture model and "organoid-PBMCs" co-culture model. These involve culturing spheroids, patient-derived organoids and isolating, expanding, and co-culturing peripheral blood mononuclear cells (PBMCs). For vivo model, PD1 humanized mice were used to establish a lung carcinoma in situ model in offspring, with blocked immune checkpoints to induce systemic inflammatory responses. Mice without PD-1 blockade served as the control group. In both organoid and "lung epithelial cell-PBMC" models, compared with the control group, the PBMC+anti-PD1 group exhibited inflammatory injury, demonstrated by the worst activity, increased collagen deposition, elevated mRNA levels of αSMA and Vimentin, higher Fibronectin expression, and higher inflammatory factors (IL6, IL1β, MPO) in the culture supernatant (p < 0.05). In vivo model also showed pulmonary inflammation, with slower weight gain of the affected mice, more obvious pulmonary interstitial thickening(Masson staining and α-SMA immunofluorescence staining), and increased immune cells and IL17A in alveolar lavage fluid and serum. This study successfully developed preclinical models of irAEs using organoid technology, conditioned co-culture and humanized mouse models, effectively reproducing inflammatory injury and offering valuable tools for irAE research.
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Affiliation(s)
- Tingyue Luo
- Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Weisheng Chen
- Department of General Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Danhui Huang
- Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Xiguang Liu
- Thoracic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Junjie Xi
- Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Zeyu Fu
- Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Junwei Chen
- Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Yuhan Du
- Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Ruijun Cai
- Thoracic Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Qi Yu
- Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Dongyu Liu
- Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Jiangzhou Du
- Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China
| | - Laiyu Liu
- Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China.
| | - Shaoxi Cai
- Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China.
| | - Hangming Dong
- Chronic Airways Diseases Laboratory, Department of Respiratory and Critical Care Medicine, Nanfang Hospital, Southern Medical University, Guangzhou, Guangdong, China.
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Zhang M, Zhan M, Song X. Echinacoside attenuates Klebsiella pneumoniae-induced pneumonia via inhibition of the TLR4/NF-κB signaling. APMIS 2025; 133:e13507. [PMID: 39757690 DOI: 10.1111/apm.13507] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2024] [Accepted: 12/03/2024] [Indexed: 01/07/2025]
Abstract
The Gram-negative bacterium Klebsiella pneumoniae (K. pneumoniae) is one major causative agent of community- and hospital-acquired pneumonia. Echinacoside (ECH) is a phenylethanoid glycoside isolated from Cistanche deserticola that possesses anti-inflammatory activity. Our research aimed to confirm whether ECH alleviates K. pneumoniae-induced pneumonia and explore the underlying regulatory mechanisms. BEAS-2B cells and BALB/c mice were infected by K. pneumoniae to establish the cellular and animal models, respectively, followed by ECH treatment. Inflammatory cytokine levels were detected by RT-qPCR and ELISA. The lung wet/dry (W/D) weight ratio and the myeloperoxidase (MPO) activity in lung tissues were examined. The pulmonary histopathologic changes were observed through hematoxylin and eosin (H&E) staining. The levels of TLR4/NF-κB pathway-associated molecules were estimated through western blotting, immunohistochemical, and immunohistochemical staining. K. pneumoniae infection caused lung histopathologic damage, enhanced MPO activity, elevated lung W/D weight ratio, and upregulated inflammatory cytokine levels in mice and promoted inflammatory cytokine expression in BEAS-2B cells, which were reversed by ECH treatment. K. pneumoniae infection-induced upregulation in TLR4, phosphorylated (p)-p65, and p-IκBα levels, and downregulation in IκBα levels in BEAS-2B cells and pneumonia mice were overturned by ECH treatment. ECH ameliorates K. pneumoniae-induced pneumonia through suppressing the TLR4/NF-κB pathway.
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Affiliation(s)
- Mi Zhang
- Department of Respiratory, Yichang Central People's Hospital, Yichang, China
| | - Ming Zhan
- Department of Respiratory, Yichang Central People's Hospital, Yichang, China
| | - Xinyu Song
- Department of Respiratory, Yichang Central People's Hospital, Yichang, China
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Xu F, Wu Q, Yang L, Sun H, Li J, An Z, Li H, Wu H, Song J, Chen W, Wu W. Modification of gut and airway microbiota on ozone-induced airway inflammation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 954:176604. [PMID: 39353487 DOI: 10.1016/j.scitotenv.2024.176604] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2024] [Revised: 09/06/2024] [Accepted: 09/27/2024] [Indexed: 10/04/2024]
Abstract
Ground-level ozone (O3) has been shown to induce airway inflammation, the underlying mechanisms remain unclear. The aim of this study was to determine whether gut and airway microbiota dysbiosis, and airway metabolic alterations were associated with O3-induced airway inflammation. Thirty-six 8-week-old male C57BL/6 N mice were divided into 2 groups: sterile water group and broad-spectrum antibiotics group (Abx). Each group was further divided into two subgroups, filtered air group (Air) and O3 group (O3), with 9 mice in each subgroup. Mice in the Air and O3 groups were exposed to filtered air or 1 ppm O3, 4 h/d for 5 consecutive days, respectively. Mice in Abx + Air and Abx + O3 groups were exposed to filtered air or O3, respectively, after drinking broad-spectrum Abx. 24 h after the final O3 exposure, mouse feces and bronchoalveolar lavage fluids (BALF) were collected and subjected to measurements of airway oxidative stress and inflammation biomarkers, 16S rRNA sequencing and metabolite profiling. Hematoxylin-eosin staining of lung tissues was applied to examine the pathological changes of lung tissue. The results showed that O3 exposure resulted in airway oxidative stress and inflammation, as well as gut and airway microbiota dysbiosis, and airway metabolism alteration. Abx pre-treatment markedly changed gut and airway microbiota and promoted O3-induced metabolic disorder and airway inflammation. Spearman correlation analyses indicated that inter-related gut and airway microbiota dysbiosis and airway metabolic disorder were associated with O3-induced airway inflammation. Together, inhaled O3 causes airway inflammation, which may implicate gut and airway microbiota dysbiosis and airway metabolic alterations.
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Affiliation(s)
- Fei Xu
- School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Qiong Wu
- School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Lin Yang
- School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Han Sun
- School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Juan Li
- School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Zhen An
- School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Huijun Li
- School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Hui Wu
- School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Jie Song
- School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China
| | - Wen Chen
- Department of Toxicology, School of Public Health, Sun Yat-sen University, Guangzhou, Guangdong 510080, China
| | - Weidong Wu
- School of Public Health, Xinxiang Medical University, Xinxiang, Henan Province 453003, China.
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Ding H, Chen XC, Wan L, Zhang YY, Rui XH, He T, Liu J, Shang ZB. Klebsiella pneumoniae alters zebrafish circadian rhythm via inflammatory pathways and is dependent on light cues. Heliyon 2024; 10:e30829. [PMID: 38770281 PMCID: PMC11103479 DOI: 10.1016/j.heliyon.2024.e30829] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 05/02/2024] [Accepted: 05/06/2024] [Indexed: 05/22/2024] Open
Abstract
Klebsiella pneumoniae is an opportunistic pathogen causing severe infections. The circadian rhythm is the internal rhythm mechanism of an organism and plays an important role in coping with changes in the 24-h circadian rhythm. Disruption of the circadian rhythm can lead to immune, behavioral, mental, and other related disorders. Whether K. pneumoniae can disrupt the circadian rhythm after infection remains unclear. Here, we examined the effects of K. pneumoniae NTUH-K2044 infection on biological rhythm and inflammation in zebrafish using behavioral assays, quantitative real-time reverse transcription PCR, neutrophil and macrophage transgenic fish, and drug treatment. The results showed that K. pneumoniae infection decreased the motor activity of zebrafish and reduced the circadian rhythm amplitude, phase, and period. The expression of core circadian rhythm-associated genes increased under light-dark conditions, whereas they were downregulated under continuous darkness. Analysis of Klebsiella pneumoniae-mediated inflammation using Tg(mpx:EGFP) and Tg(mpeg:EGFP) transgenic zebrafish, expressing fluorescent neutrophils and macrophages, respectively, showed increased induction of inflammatory cells, upregulated expression of inflammatory factor genes, and stronger inflammatory responses under light-dark conditions. These effects were reversed by the anti-inflammatory drug G6PDi-1, and the expression of clock genes following K. pneumoniae treatment was disrupted. We determined the relationship among K. pneumoniae, inflammation, and the circadian rhythm, providing a theoretical reference for studying circadian rhythm disorders caused by inflammation.
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Affiliation(s)
- Hui Ding
- Department of Laboratory Medicine, Affiliated Wuxi Fifth Hospital of Jiangnan University, Wuxi, 214005, China
| | - Xiao-chun Chen
- Department of Laboratory Medicine, Taizhou Second People's Hospital, Taizhou, 225411, China
| | - Lin Wan
- Department of Laboratory Medicine, Jiangnan University Medical Center, Wuxi, 214000, China
| | - Ying-ying Zhang
- Department of Laboratory Medicine, Affiliated Wuxi Fifth Hospital of Jiangnan University, Wuxi, 214005, China
| | - Xiao-hong Rui
- Department of Laboratory Medicine, Affiliated Wuxi Fifth Hospital of Jiangnan University, Wuxi, 214005, China
| | - Tian He
- Department of Laboratory Medicine, Affiliated Wuxi Fifth Hospital of Jiangnan University, Wuxi, 214005, China
| | - Jun Liu
- Department of Laboratory Medicine, Affiliated Wuxi Fifth Hospital of Jiangnan University, Wuxi, 214005, China
| | - Zhong-bo Shang
- Department of Laboratory Medicine, Wuxi Huishan District People's Hospital, Wuxi, 214000, China
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Jiang W, Liu J, Zhao X, Yang W. Melatonin-induced upregulation of telomerase activity interferes with macrophage mitochondrial metabolism and suppresses NLRP3 inflammasome activation in the treatment of Pneumonia. Heliyon 2024; 10:e29681. [PMID: 38665558 PMCID: PMC11044047 DOI: 10.1016/j.heliyon.2024.e29681] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2023] [Revised: 04/10/2024] [Accepted: 04/12/2024] [Indexed: 04/28/2024] Open
Abstract
Objective This study aims to investigate the effects of melatonin-induced upregulation of telomerase activity on mitochondrial metabolism and NLRP3 inflammasome activation in macrophages, with the ultimate goal of elucidating potential therapeutic implications for pneumonia treatment. Materials and methods Macrophages were treated with melatonin to assess its impact on telomerase activity. Mitochondrial function was evaluated through the measurement of reactive oxygen species (ROS) levels and cellular energy production. NLRP3 inflammasome activation was assessed by examining the production of inflammatory cytokines, such as interleukin-1β (IL-1β). The expression levels of key proteins involved in mitochondrial metabolism and NLRP3 inflammasome signaling were also analyzed. Results Our findings demonstrated that melatonin treatment significantly upregulated telomerase activity in macrophages. This was associated with a reduction in ROS levels and enhanced cellular energy production, indicating improved mitochondrial function. Moreover, melatonin treatment suppressed NLRP3 inflammasome activation, resulting in reduced secretion of IL-1β. The expression levels of proteins involved in mitochondrial metabolism and NLRP3 inflammasome signaling were modulated by melatonin. Conclusion These results suggest that melatonin-induced upregulation of telomerase activity can interfere with mitochondrial metabolism and inhibit NLRP3 inflammasome activation in macrophages. This indicates a potential therapeutic role for melatonin in the treatment of pneumonia. Understanding the molecular mechanisms underlying these effects may lead to the development of novel therapeutic strategies targeting mitochondria and NLRP3 inflammasome activation for the management of pneumonia. Further investigations are warranted to fully uncover the therapeutic potential of melatonin and its implications for pneumonia treatment.
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Affiliation(s)
- Wei Jiang
- Department of Infectious Diseases, Tianjin First Central Hospital, Tianjin, 300192, China
| | - Jun Liu
- Department of Infectious Diseases, Tianjin First Central Hospital, Tianjin, 300192, China
| | - Xuequn Zhao
- Department of Infectious Diseases, Tianjin First Central Hospital, Tianjin, 300192, China
| | - Wenjie Yang
- Department of Infectious Diseases, Tianjin First Central Hospital, Tianjin, 300192, China
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Xu Y, Zhang C, Cai D, Zhu R, Cao Y. Exosomal miR-155-5p drives widespread macrophage M1 polarization in hypervirulent Klebsiella pneumoniae-induced acute lung injury via the MSK1/p38-MAPK axis. Cell Mol Biol Lett 2023; 28:92. [PMID: 37953267 PMCID: PMC10641976 DOI: 10.1186/s11658-023-00505-1] [Citation(s) in RCA: 30] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2023] [Accepted: 10/24/2023] [Indexed: 11/14/2023] Open
Abstract
BACKGROUND Hypervirulent Klebsiella pneumoniae (hvKp) infection-induced sepsis-associated acute lung injury (ALI) has emerged as a significant clinical challenge. Increasing evidence suggests that activated inflammatory macrophages contribute to tissue damage in sepsis. However, the underlying causes of widespread macrophage activation remain unclear. METHODS BALB/c mice were intravenously injected with inactivated hvKp (iHvKp) to observe lung tissue damage, inflammation, and M1 macrophage polarization. In vitro, activated RAW264.7 macrophage-derived exosomes (iHvKp-exo) were isolated and their role in ALI formation was investigated. RT-PCR was conducted to identify changes in exosomal miRNA. Bioinformatics analysis and dual-luciferase reporter assays were performed to validate MSK1 as a direct target of miR-155-5p. Further in vivo and in vitro experiments were conducted to explore the specific mechanisms involved. RESULTS iHvKp successfully induced ALI in vivo and upregulated the expression of miR-155-5p. In vivo, injection of iHvKp-exo induced inflammatory tissue damage and macrophage M1 polarization. In vitro, iHvKp-exo was found to promote macrophage inflammatory response and M1 polarization through the activation of the p38-MAPK pathway. RT-PCR revealed exposure time-dependent increased levels of miR-155-5p in iHvKp-exo. Dual-luciferase reporter assays confirmed the functional role of miR-155-5p in mediating iHvKp-exo effects by targeting MSK1. Additionally, inhibition of miR-155-5p reduced M1 polarization of lung macrophages in vivo, resulting in decreased lung injury and inflammation induced by iHvKp-exo or iHvKp. CONCLUSIONS The aforementioned results indicate that exosomal miR-155-5p drives widespread macrophage inflammation and M1 polarization in hvKp-induced ALI through the MSK1/p38-MAPK Axis.
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Affiliation(s)
- Yihan Xu
- Department of Clinical Laboratory, Fujian Medical University Union Hospital, Fuzhou, 350001, People's Republic of China
| | - Chunying Zhang
- Department of Clinical Laboratory, Fujian Medical University Union Hospital, Fuzhou, 350001, People's Republic of China
| | - Danni Cai
- Central Laboratory, Fujian Medical University Union Hospital, Fuzhou, 350001, People's Republic of China
| | - Rongping Zhu
- Department of Clinical Laboratory, Fujian Medical University Union Hospital, Fuzhou, 350001, People's Republic of China
| | - Yingping Cao
- Department of Clinical Laboratory, Fujian Medical University Union Hospital, Fuzhou, 350001, People's Republic of China.
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10
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Hu R, Wan L, Liu X, Lu J, Hu X, Zhang X, Zhang M. K. pneumoniae and M. smegmatis infect epithelial cells via different strategies. J Thorac Dis 2023; 15:4396-4412. [PMID: 37691650 PMCID: PMC10482649 DOI: 10.21037/jtd-23-493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2023] [Accepted: 07/07/2023] [Indexed: 09/12/2023]
Abstract
Background As the first line of defense, epithelial cells play a vital role in the initiation and control of both innate and adaptive immunity, which participate in the development of disease. Despite its therapeutic significance, little is understood about the specific interaction between pathogenic microorganisms and lung epithelial cells. Methods In this study, we performed a head-to-head comparison of the virulence and infection mechanisms of Klebsiella pneumoniae (K. pneumoniae) and Mycobacterium smegmatis (M. smegmatis), which represent Gram-negative/positive respiratory pathogens, respectively, in lung epithelial cell models for the first time. Results Through scanning electron microscopy combined with bacterial infection experiments, we confirmed the ability of K. pneumoniae and M. smegmatis strains to form biofilm and cord factor out of the cell wall. M. smegmatis has stronger adhesion and intracellular retention ability, while K. pneumoniae is more likely to induce acute infection. These pathogens could stay and proliferate in lung epithelial cells and stimulate the secretion of specific cytokines and chemokines through a gene transcription regulator. M. smegmatis infection can promote crosstalk among epithelial cells and other immune cells in the lung from a very early stage by prompting the secretion of pro-inflammatory cytokines. Meanwhile, there were significant correlations between K. pneumonia infection and higher levels of interleukin-15 (IL-15), interleukin-1Rα (IL-1Rα), fibroblast growth factor (FGF) basic, and granulocyte colony-stimulating factor (G-CSF). At the same time, K. pneumonia infection also led to changes in the expression of cytoskeletal proteins in epithelial cells. Conclusions Our results emphasized the immunoprotection and immunomodulation of lung epithelial cells against exogenous pathogenic microorganisms, indicating that different pathogens damaged the host through different strategies and induced varying innate immune responses. At the same time, they provided important clues and key immune factors for dealing with complicated pulmonary infections.
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Affiliation(s)
- Renjing Hu
- Department of Laboratory Medicine, Jiangnan University Medical Center, Wuxi, China
| | - Lin Wan
- Department of Laboratory Medicine, Jiangnan University Medical Center, Wuxi, China
| | - Xiaoyun Liu
- Center Laboratory, The Affiliated Hospital of Xuzhou Medical University, Xuzhou, China
| | - Jie Lu
- Department of Laboratory Medicine, Jiangnan University Medical Center, Wuxi, China
| | - Xichi Hu
- Department of Laboratory Medicine, Jiangnan University Medical Center, Wuxi, China
| | - Xiaoli Zhang
- Department of Dermatology, Jiangnan University Medical Center, Wuxi, China
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11
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Wang X, Bi C, Xin X, Zhang M, Fu H, Lan L, Wang M, Yan Z. Pyroptosis, apoptosis, and autophagy are involved in infection induced by two clinical Klebsiella pneumoniae isolates with different virulence. Front Cell Infect Microbiol 2023; 13:1165609. [PMID: 37223846 PMCID: PMC10200925 DOI: 10.3389/fcimb.2023.1165609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Accepted: 04/18/2023] [Indexed: 05/25/2023] Open
Abstract
Klebsiella pneumoniae can cause widespread infections and is an important factor of hospital- and community-acquired pneumonia. The emergence of hypervirulent K. pneumoniae poses a serious clinical therapeutic challenge and is associated with a high mortality. The goal of this work was to investigate the influence of K. pneumoniae infection on host cells, particularly pyroptosis, apoptosis, and autophagy in the context of host-pathogen interactions to better understand the pathogenic mechanism of K. pneumoniae. Two clinical K. pneumoniae isolates, one classical K. pneumoniae isolate and one hypervirulent K. pneumoniae isolate, were used to infect RAW264.7 cells to establish an in vitro infection model. We first examined the phagocytosis of macrophages infected with K. pneumoniae. Lactate dehydrogenase (LDH) release test, and calcein-AM/PI double staining was conducted to determine the viability of macrophages. The inflammatory response was evaluated by measuring the pro-inflammatory cytokines and reactive oxygen species (ROS) production. The occurrence of pyroptosis, apoptosis, and autophagy was assessed by detecting the mRNA and protein levels of the corresponding biochemical markers. In addition, mouse pneumonia models were constructed by intratracheal instillation of K. pneumoniae for in vivo validation experiments. As for results, hypervirulent K. pneumoniae was much more resistant to macrophage-mediated phagocytosis but caused more severe cellular damage and lung tissues damage compared with classical K. pneumoniae. Moreover, we found increased expression of NLRP3, ASC, caspase-1, and GSDMD associated with pyroptosis in macrophages and lung tissues, and the levels were much higher following hypervirulent K. pneumoniae challenge. Both strains induced apoptosis in vitro and in vivo; the higher apoptosis proportion was observed in infection caused by hypervirulent K. pneumoniae. Furthermore, classical K. pneumoniae strongly triggered autophagy, while hypervirulent K. pneumoniae weakly activated this process. These findings provide novel insights into the pathogenesis of K. pneumoniae and may form the foundation for the future design of treatments for K. pneumoniae infection.
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Affiliation(s)
- Xueting Wang
- Institute of Medical Faculty, Qingdao University, Qingdao, China
| | - Chunxia Bi
- Department of Clinical Laboratory, Qingdao Municipal Hospital, Qingdao, China
| | - Xiaoni Xin
- Department of Clinical Laboratory, Qingdao Municipal Hospital, Qingdao, China
| | - Mengmeng Zhang
- Department of Clinical Laboratory, Shandong Provincial Second People’s Hospital, Jinan, China
| | - Hengxia Fu
- Department of Clinical Laboratory, Linyi Central Hospital, Linyi, China
| | - Lei Lan
- Department of Blood Transfusion, Qingdao Women and Children’s Hospital, Qingdao, China
| | - Mengyuan Wang
- Department of Clinical Laboratory, Jinan Children’s Hospital, Jinan, China
| | - Zhiyong Yan
- College of Basic Medicine, Medical Faculty of Qingdao University, Qingdao, China
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