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Pioselli B, Salomone F, Mazzola G, Amidani D, Sgarbi E, Amadei F, Murgia X, Catinella S, Villetti G, De Luca D, Carnielli V, Civelli M. Pulmonary surfactant: a unique biomaterial with life-saving therapeutic applications. Curr Med Chem 2021; 29:526-590. [PMID: 34525915 DOI: 10.2174/0929867328666210825110421] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2021] [Revised: 06/26/2021] [Accepted: 06/29/2021] [Indexed: 11/22/2022]
Abstract
Pulmonary surfactant is a complex lipoprotein mixture secreted into the alveolar lumen by type 2 pneumocytes, which is composed by tens of different lipids (approximately 90% of its entire mass) and surfactant proteins (approximately 10% of the mass). It is crucially involved in maintaining lung homeostasis by reducing the values of alveolar liquid surface tension close to zero at end-expiration, thereby avoiding the alveolar collapse, and assembling a chemical and physical barrier against inhaled pathogens. A deficient amount of surfactant or its functional inactivation is directly linked to a wide range of lung pathologies, including the neonatal respiratory distress syndrome. This paper reviews the main biophysical concepts of surfactant activity and its inactivation mechanisms, and describes the past, present and future roles of surfactant replacement therapy, focusing on the exogenous surfactant preparations marketed worldwide and new formulations under development. The closing section describes the pulmonary surfactant in the context of drug delivery. Thanks to its peculiar composition, biocompatibility, and alveolar spreading capability, the surfactant may work not only as a shuttle to the branched anatomy of the lung for other drugs but also as a modulator for their release, opening to innovative therapeutic avenues for the treatment of several respiratory diseases.
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Affiliation(s)
| | | | | | | | - Elisa Sgarbi
- Preclinical R&D, Chiesi Farmaceutici, Parma. Italy
| | | | - Xabi Murgia
- Department of Biotechnology, GAIKER Technology Centre, Zamudio. Spain
| | | | | | - Daniele De Luca
- Division of Pediatrics and Neonatal Critical Care, Antoine Béclère Medical Center, APHP, South Paris University Hospitals, Paris, France; Physiopathology and Therapeutic Innovation Unit-U999, South Paris-Saclay University, Paris. France
| | - Virgilio Carnielli
- Division of Neonatology, G Salesi Women and Children's Hospital, Polytechnical University of Marche, Ancona. Italy
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Yuan H, Gao Z, Lu X, Hu F. Role of collectin-11 in innate defence against uropathogenic Escherichia coli infection. Innate Immun 2020; 27:50-60. [PMID: 33241978 PMCID: PMC7780352 DOI: 10.1177/1753425920974766] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022] Open
Abstract
Classical collectins (surfactant protein A and D) play a significant role in innate immunity and host defence in uropathogenic Escherichia coli (UPEC)-induced urinary tract infection (UTI). However, the functions of collectin-11 (CL-11) with respect to UPEC and UTI remain largely unexplored. This study aimed to investigate the effect of CL-11 on UPEC and its role in UTI. We further examined its modulatory effect on inflammatory reactions in proximal tubular epithelial cells (PTECs). The present study provides evidence for the effect of CL-11 on the growth, agglutination, binding, epithelial adhesion and invasion of UPEC. We found increased basal levels of phosphorylated p38 MAPK and human cytokine homologue (keratinocyte-derived chemokine) expression in CL-11 knockdown PTECs. Furthermore, signal regulatory protein α blockade reversed the increased basal levels of inflammation associated with CL-11 knockdown in PTECs. Additionally, CL-11 knockdown effectively inhibited UPEC-induced p38 MAPK phosphorylation and cytokine production in PTECs. These were further inhibited by CD91 blockade. We conclude that CL-11 functions as a mediator of innate immunity via direct antibacterial roles as well as dual modulatory roles in UPEC-induced inflammatory responses during UTI. Thus, the study findings suggest a possible function for CL-11 in defence against UTI.
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Affiliation(s)
- Hai Yuan
- Department of Nephrology, 74731Xiangyang Central Hospital, Affiliated Hospital of 118302Hubei University of Arts and Science, PR China
| | - Zhao Gao
- Department of Nephrology, 74731Xiangyang Central Hospital, Affiliated Hospital of 118302Hubei University of Arts and Science, PR China
| | - Xiaohan Lu
- Department of Nephrology, 74731Xiangyang Central Hospital, Affiliated Hospital of 118302Hubei University of Arts and Science, PR China
| | - Fengqi Hu
- Department of Nephrology, 74731Xiangyang Central Hospital, Affiliated Hospital of 118302Hubei University of Arts and Science, PR China
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3
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King SD, Chen SY. Recent progress on surfactant protein A: cellular function in lung and kidney disease development. Am J Physiol Cell Physiol 2020; 319:C316-C320. [PMID: 32639871 DOI: 10.1152/ajpcell.00195.2020] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Pulmonary surfactant is a heterogeneous active surface complex made up of lipids and proteins. The major glycoprotein in surfactant is surfactant protein A (SP-A), which is released into the alveolar lumen from cytoplasmic lamellar bodies in type II alveolar epithelial cells. SP-A is involved in phospholipid absorption. SP-A together with other surfactant proteins and phospholipids prevent alveolar collapse during respiration by decreasing the surface tension of the air-liquid interface. Additionally, SP-A interacts with pathogens to prevent their propagation and regulate host immune responses. Studies in human and animal models have shown that deficiencies or mutations in surfactant components result in various lung or kidney pathologies, suggesting a role for SP-A in the development of lung and kidney diseases. In this mini-review, we discuss the current understanding of SP-A functions, recent findings of its dysfunction in specific lung and kidney pathologies, and how SP-A has been used as a biomarker to detect the outcome of lung diseases.
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Affiliation(s)
- Skylar D King
- Department of Surgery, University of Missouri School of Medicine, Columbia, Missouri
| | - Shi-You Chen
- Department of Surgery, University of Missouri School of Medicine, Columbia, Missouri.,Department of Molecular Pharmacology and Physiology, University of Missouri School of Medicine, Columbia, Missouri
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Pan Y, Wang J, Xue Y, Zhao J, Li D, Zhang S, Li K, Hou Y, Fan H. GSKJ4 Protects Mice Against Early Sepsis via Reducing Proinflammatory Factors and Up-Regulating MiR-146a. Front Immunol 2018; 9:2272. [PMID: 30337925 PMCID: PMC6179039 DOI: 10.3389/fimmu.2018.02272] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2018] [Accepted: 09/12/2018] [Indexed: 01/04/2023] Open
Abstract
Sepsis, defined as life-threatening organ dysfunction, is one of the most common causes of mortality in intensive care units with limited therapeutic options. However, the mechanism underlying the regulation of epigenetics on sepsis remains largely undefined. Here we showed that JMJD3, the histone lysine demethylase, played a critical role in the epigenetic regulation of innate immunity during early sepsis. Pharmacological inhibition of JMJD3 by GSKJ4 protected mice against early septic death and reduced pro-inflammatory cytokine interleukin-1β (IL-1β) production as well as IL-6, tumor necrosis factor-α (TNF-α), and monocyte chemotactic protein-1 (MCP-1) expression. Interestingly, GSKJ4 up-regulated the transcription of anti-inflammatory microRNA-146a (miR-146a) in peritoneal macrophages from septic mice. Mechanistically, JMJD3 negatively regulated the transcription of miR-146a via its demethylation of H3K27me3 on the promoter of miR-146a. Moreover, the transcription of miR-146a was positively regulated by nuclear factor-κB (NF-κB) p65. Inhibition of NF-κB p65 promoted JMJD3 binding to miR-146a promoter and decreased the tri-methylation level of H3K27, while the inhibition of JMJD3 did not affect the recruitment of NF-κB p65 to miR-146a promoter. These results highlight an epigenetic mechanism by which JMJD3 was inhibited by NF-κB p65 from binding to miR-146a promoter to promote the anti-inflammatory response. Taken together, our findings uncover a key role for JMJD3 in modulating the miR-146a transcription and shed light on the JMJD3 inhibitors could be potential therapeutic agents for early sepsis therapy.
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Affiliation(s)
- Yuchen Pan
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing, China
| | - Jiali Wang
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing, China
| | - Yaxian Xue
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing, China
| | - Jiaojiao Zhao
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing, China
| | - Dan Li
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing, China
| | - Shaolong Zhang
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
| | - Kuanyu Li
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing, China
| | - Yayi Hou
- State Key Laboratory of Pharmaceutical Biotechnology, Division of Immunology, Medical School, Nanjing University, Nanjing, China.,Jiangsu Key Laboratory of Molecular Medicine, Nanjing, China
| | - Hongye Fan
- State Key Laboratory of Natural Medicines, School of Life Science and Technology, China Pharmaceutical University, Nanjing, China
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Bassorgun CI, Sayar EC, Baykara M, Kankavi O. Alteration of surfactant protein A expression in renal cell carcinoma. Biotech Histochem 2018; 93:519-525. [PMID: 29932013 DOI: 10.1080/10520295.2018.1472296] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022] Open
Abstract
Surfactant protein-A (SP-A) belongs to a family of collagen-containing C-type lectins called collectins. SP-A is expressed by renal tubule epithelial cells. We investigated the distribution of SP-A in renal cell carcinomas (RCC) using immunohistochemical techniques and western blotting. We used 35 formalin fixed, paraffin embedded (FFPE) RCC tissue samples. We compared results with clinico-pathological parameters of RCC including age, sex, Fuhrman grade, tumor volume, tumor node metastasis (TNM) and clinical stage. SP-A was localized in the glomerulus and renal tubule epithelium in nontumor tissue and strong SP-A immunoreactivity was observed in tumor tissue. SP-A was expressed in the RCC tumor cells (64%) and nontumor cells (34%) in males and RCC tumor cells (90%) and nontumor cells (30%) in females. There was a significant correlation between SP-A immunoreactivity in tumor cells and gender, age, tumor diameter, Fuhrman grade and tumor diameter. Western blot analysis supported the immunohistochemical findings. We present evidence for involvement of SP-A in RCC and suggest that increased SP-A expression in RCC is associated with favorable prognosis.
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Affiliation(s)
- C I Bassorgun
- a Departments of Pathology, Faculty of Medicine , University of Akdeniz , Antalya , Turkey
| | - E C Sayar
- a Departments of Pathology, Faculty of Medicine , University of Akdeniz , Antalya , Turkey
| | - M Baykara
- b Department of Urology, Faculty of Medicine , University of Akdeniz , Antalya , Turkey
| | - O Kankavi
- c Department of Biochemistry, Faculty of Veterinary Medicine , The University of Mehmet Akif Ersoy , Burdur , Turkey
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Collectins in urinary tract and kidney diseases. Int Urol Nephrol 2017; 50:695-703. [PMID: 29071557 DOI: 10.1007/s11255-017-1728-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2017] [Accepted: 10/16/2017] [Indexed: 10/18/2022]
Abstract
The innate immune system serves as the frontline defense against invading pathogens and initiates an inflammatory response to microorganisms. Collectins are C-type lectins that are structurally characterized by a collagen-like sequence and a carbohydrate recognition domain. Moreover, they are widely expressed throughout the body and are involved in the innate immunity against a variety of pathogens, regulating inflammation, and protecting the lungs from pathogens. Recently, two classical collectins, surfactant protein A (SP-A) and surfactant protein D (SP-D), as well as novel collectin 11, were found present in urinary tract tissues. They are increasingly recognized as key players in activating the humoral arm of innate immunity and host defense in urinary tract and kidney diseases, although their biological features, functions, and mechanisms in this regard remain largely unclear. In this review, we aim to integrate results reported by ourselves and others to summarize and gain a better understanding of the functions of collectins (SP-A, SP-D, and collectin 11) in urinary tract and kidney diseases.
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Liu J, Li G, Xie WJ, Wang L, Zhang R, Huang KS, Zhou QS, Chen DC. Lipopolysaccharide Stimulates Surfactant Protein-A in Human Renal Epithelial HK-2 Cells through Upregulating Toll-like Receptor 4 Dependent MEK1/2-ERK1/2-NF-κB Pathway. Chin Med J (Engl) 2017; 130:1236-1243. [PMID: 28485325 PMCID: PMC5443031 DOI: 10.4103/0366-6999.205853] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2017] [Indexed: 11/05/2022] Open
Abstract
BACKGROUND Surfactant protein-A (SP-A) contributes to the regulation of sepsis-induced acute kidney injury. In a previous study, we demonstrated that the expression of SP-A in the human renal tubular epithelial (HK-2) cells can be stimulated by lipopolysaccharide (LPS). The present study evaluated the possible signal-transducing mechanisms of LPS-induced SP-A biosynthesis in the HK-2 cells. METHODS Tetrazolium salt colorimetry (MTT) assay was used to detect cell viability of HK-2 cells after LPS stimulation on different time points. HK-2 cells were stimulated with 100 ng/ml of LPS for different durations to determine the effects of LPS on SP-A and toll-like receptor 4 (TLR4) messenger RNA (mRNA) expression, as well as phosphorylation of mitogen-activated/extracellular signal-regulated kinase (MEK) 1, extracellular signal-regulated kinase 1/2 (ERK1/2), p38 mitogen-activated protein kinase (p38MAPK), and nuclear factor-kappa B (NF-κB) inhibitor-alpha (IkB-α). Then, HK-2 cells were pretreated with CLI-095, a TLR4 inhibitor, to analyze mRNA and protein levels of SP-A and TLR4 and expression of NF-κB in the cytoplasm and nucleus of HK-2 before LPS exposure. RESULTS HK-2 cells exposed to 100 ng/ml of LPS for 1, 6, and 24 h did not affect cell viability which showed no toxic effect of 100 ng/ml LPS on cells (P = 0.16); however, the biosynthesis of SP-A mRNA and protein in HK-2 cells was significantly increased (P = 0.02). As to the mechanism, LPS enhanced transmembrane receptor TLR4 protein expression. Sequentially, LPS time dependently augmented phosphorylation of MEK1, ERK1/2, and p38MAPK. In addition, levels of phosphorylated IκB-α and nuclear NF-κB were augmented with LPS exposure for 2 h. LPS-induced SP-A and TLR4 mRNA as well as NF-κB expression were significantly inhibited by pretreatment with CLI-095. CONCLUSIONS The present study exhibited that LPS can increase SP-A synthesis in human renal epithelial cells through sequentially activating the TLR4-related MEK1-ERK1/2-NF-κB-dependent pathway.
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Affiliation(s)
- Jiao Liu
- Department of Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, China
| | - Guang Li
- Department of Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, China
| | - Wen-Jie Xie
- Department of Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, China
| | - Lu Wang
- Department of Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, China
| | - Rui Zhang
- Department of Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, China
| | - Ke-Sheng Huang
- Department of Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, China
| | - Qing-Shan Zhou
- Department of Critical Care Medicine, Renmin Hospital of Wuhan University, Wuhan, Hubei 430060, China
| | - De-Chang Chen
- Department of Critical Care Medicine, Ruijin Hospital, Shanghai Jiaotong University, Shanghai 200025, China
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8
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Yang X, Yan J, Feng J. Surfactant protein A is expressed in the central nervous system of rats with experimental autoimmune encephalomyelitis, and suppresses inflammation in human astrocytes and microglia. Mol Med Rep 2017; 15:3555-3565. [PMID: 28393255 PMCID: PMC5436200 DOI: 10.3892/mmr.2017.6441] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2015] [Accepted: 02/13/2017] [Indexed: 12/03/2022] Open
Abstract
The collectin surfactant protein-A (SP-A), a potent host defense molecule, is well recognized for its role in the maintenance of pulmonary homeostasis and the modulation of inflammatory responses. While previous studies have detected SP-A in numerous extrapulmonary tissues, there is still a lack of information regarding its expression in central nervous system (CNS) and potential effects in neuroinflammatory diseases, such as multiple sclerosis (MS). The present study used experimental autoimmune encephalomyelitis (EAE), the most commonly used animal model of MS, to investigate the expression of SP-A in the CNS at different stages of disease progression. In addition, in vitro experiments with lipopolysaccharide (LPS)-stimulated human astrocytes and microglia were performed to investigate the potential role of SP-A in the modulation of CNS inflammatory responses. The results of the present study demonstrated widespread distribution of SP-A in the rat CNS, and also identified specific expression patterns of SP-A at different stages of EAE. In vitro, the current study revealed that treatment of human astrocytes and microglia with LPS promoted SP-A expression in a dose-dependent manner. Furthermore, exogenous SP-A protein significantly decreased Toll-like receptor 4 and nuclear factor-κB expression, and reduced interleukin-1β and tumor necrosis factor-α levels. The results of the current study indicate a potential role for SP-A in the modulation of CNS inflammatory responses.
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Affiliation(s)
- Xue Yang
- Department of Neurology, Shengjing Hospital, Affiliated Hospital of China Medical University. Shenyang, Liaoning 110004, P.R. China
| | - Jun Yan
- Department of Neurology, Shengjing Hospital, Affiliated Hospital of China Medical University. Shenyang, Liaoning 110004, P.R. China
| | - Juan Feng
- Department of Neurology, Shengjing Hospital, Affiliated Hospital of China Medical University. Shenyang, Liaoning 110004, P.R. China
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Vieira F, Kung JW, Bhatti F. Structure, genetics and function of the pulmonary associated surfactant proteins A and D: The extra-pulmonary role of these C type lectins. Ann Anat 2017; 211:184-201. [PMID: 28351530 DOI: 10.1016/j.aanat.2017.03.002] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2016] [Revised: 03/08/2017] [Accepted: 03/09/2017] [Indexed: 10/19/2022]
Abstract
The collectins family encompasses several collagenous Ca2+-dependent defense lectins that are described as pathogen recognition molecules. They play an important role in both adaptive and innate immunity. Surfactant proteins A and D are two of these proteins which were initially discovered in association with surfactant in the pulmonary system. The structure, immune and inflammatory functions, and genetic variations have been well described in relation to their roles, function and pathophysiology in the pulmonary system. Subsequently, these proteins have been discovered in a wide range of other organs and organ systems. The role of these proteins outside the pulmonary system is currently an active area of research. This review intends to provide a current overview of the genetics, structure and extra-pulmonary functions of the surfactant collectin proteins.
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Affiliation(s)
- Frederico Vieira
- Neonatal Perinatal Medicine, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States.
| | - Johannes W Kung
- Neonatal Perinatal Medicine, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States.
| | - Faizah Bhatti
- Neonatal Perinatal Medicine, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States; Department of Ophthalmology, Dean McGee Eye Institute, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States; Oklahoma Center for Neurosciences, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States.
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Zhao YL, Zhang L, Yang YY, Tang Y, Zhou JJ, Feng YY, Cui TL, Liu F, Fu P. Resolvin D1 Protects Lipopolysaccharide-induced Acute Kidney Injury by Down-regulating Nuclear Factor-kappa B Signal and Inhibiting Apoptosis. Chin Med J (Engl) 2017; 129:1100-7. [PMID: 27098797 PMCID: PMC4852679 DOI: 10.4103/0366-6999.180517] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Background: Resolvin D1 (RvD1) is a newly found anti-inflammatory bioactive compound derived from polyunsaturated fatty acids. The current study aimed to explore the protective effect of RvD1 on lipopolysaccharide (LPS)-induced acute kidney injury (AKI) and its possible mechanism. Methods: Both in vivo and in vitro studies were conducted. Male BALB/c mice were randomly divided into control group (saline), LPS group (LPS 5 mg/kg), RvD1 group (RvD1 5 μg/kg + LPS 5 mg/kg), and blockage group (Boc-MLP 5 μg/kg + RvD1 5 μg/kg + LPS 5 mg/kg). Boc-MLP is a RvD1 receptor blocker. The mice were intraperitoneally injected with these drugs and recorded for general condition for 48 h, while the blood and kidneys were harvested at 2, 6, 12, 24, and 48 h time points, respectively (n = 6 in each group at each time point). Human proximal tubule epithelial cells (HK-2) were randomly divided into control group (medium only), LPS group (LPS 5 μg/ml), RvD1 group (RvD1 10 ng/ml + LPS 5 μg/ml), and blockage group (Boc-MLP 10 ng/ml + RvD1 10 ng/ml + LPS 5 μg/ml). The cells were harvested for RNA at 2, 4, 6, 12, and 24 h time points, respectively (n = 6 in each group at each time point). Blood creatinine was tested by using an Abbott i-STAT portable blood gas analyzer. Tumor necrosis factor-α (TNF-α) level was detected by ELISA. Kidney pathology was observed under hematoxylin and eosin (HE) staining and transmission electron microscope (TEM). We hired immune-histological staining, Western blotting, and fluorescence quantitative polymerase chain reaction to detect the expression of RvD1 receptor ALX, nuclear factor-kappa B (NF-κB) signaling pathway as well as caspase-3. Kidney apoptosis was evaluated by TUNEL staining. Results: RvD1 receptor ALX was detected on renal tubular epithelials. Kaplan–Meier analysis indicated that RvD1 improved 48 h animal survival (80%) compared with LPS group (40%) and RvD1 blockage group (60%), while RvD1 also ameliorated kidney pathological injury in HE staining and TEM scan. After LPS stimulation, the mRNA expression of toll-like receptor 4, myeloid differentiation factor 88, and TNF-α in both mice kidneys and HK-2 cells were all up-regulated, while RvD1 substantially inhibited the up-regulation of these genes. Western blotting showed that the phosphorylated-IκB/IκB ratio in LPS group was significantly higher than that in the control group, which was inhibited in the RvD1 group. RvD1 could inhibit the up-regulation of cleaved-caspase-3 protein stimulated by LPS, which was prohibited in RvD1 blockage group. RvD1 group also had a lower proportion of apoptotic nuclei in mice kidney by TUNEL staining compared with LPS group. Conclusion: In LPS-induced AKI, RvD1 could decrease TNF-α level, ameliorate kidney pathological injury, protect kidney function, and improve animal survival by down-regulating NF-κB inflammatory signal as well as inhibiting renal cell apoptosis.
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Affiliation(s)
| | | | | | | | | | | | | | | | - Ping Fu
- Division of Nephrology, West China Hospital, Sichuan University, Chengdu, Sichuan 610041; West China Kidney Research Institute, Sichuan University, Chengdu, Sichuan 610041, China
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11
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Tian S, Li C, Ran R, Chen SY. Surfactant protein A deficiency exacerbates renal interstitial fibrosis following obstructive injury in mice. Biochim Biophys Acta Mol Basis Dis 2016; 1863:509-517. [PMID: 27916681 DOI: 10.1016/j.bbadis.2016.11.032] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2016] [Revised: 11/20/2016] [Accepted: 11/30/2016] [Indexed: 11/20/2022]
Abstract
Renal interstitial fibrosis is an inevitable consequence of virtually every type of chronic kidney disease. The underlying mechanisms, however, are not completely understood. In the present study, we identified surfactant protein A (SP-A) as a novel protein factor involved in the renal fibrosis induced by unilateral ureter obstruction (UUO). UUO induced SP-A expression in mouse kidney epithelium, likely due to the increased acidic stress and inflammation. Interestingly, SP-A deficiency aggravated UUO-prompted kidney structural damage, macrophage accumulation, and tubulointerstitial fibrosis. SP-A deficiency appeared to worsen the fibrosis by enhancing interstitial myofibroblast accumulation. Moreover, SP-A deficiency increased the expression of TGF-β1, the major regulator of kidney fibrosis, particularly in the interstitial cells. Mechanistically, SP-A deficiency increased the expression and release of high mobility group box 1 (HMGB1), a factor regulating TGF-β expression/signaling and implicated in renal fibrosis. SP-A also blocked HMGB1 activities in inducing TGF-β1 expression and myofibroblast transdifferentiation from kidney fibroblasts, demonstrating that SP-A protected kidney by impeding both the expression and fibrogenic function of HMGB1. Since SP-A physically interacted with HMGB1 both in vitro and in kidney tissue in vivo, SP-A may exert its protective role by binding to HMGB1 and thus titrating its activity during UUO-induced renal fibrosis.
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Affiliation(s)
- Shaojiang Tian
- Department of Physiology & Pharmacology, University of Georgia, Athens, GA, USA; Department of Nephrology, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei, China.
| | - Chenxiao Li
- Department of Physiology & Pharmacology, University of Georgia, Athens, GA, USA
| | - Ran Ran
- Department of Physiology & Pharmacology, University of Georgia, Athens, GA, USA; Department of Nephrology, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei, China
| | - Shi-You Chen
- Department of Physiology & Pharmacology, University of Georgia, Athens, GA, USA; Department of Nephrology, Renmin Hospital, Hubei University of Medicine, Shiyan, Hubei, China
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12
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Hu F, Ding G, Zhang Z, Gatto LA, Hawgood S, Poulain FR, Cooney RN, Wang G. Innate immunity of surfactant proteins A and D in urinary tract infection with uropathogenic Escherichia coli. Innate Immun 2015; 22:9-20. [PMID: 26511057 DOI: 10.1177/1753425915609973] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Accepted: 09/14/2015] [Indexed: 12/20/2022] Open
Abstract
To investigate the effects of surfactant proteins A and D (SP-A and SP-D, respectively) in urinary tract infection (UTI), SP-A and SP-D double knockout (SP-A/D KO) and wild type (WT) C57BL/6 female mice were infected with uropathogenic Escherichia coli by intravesical inoculation. Compared with WT mice SP-A/D KO mice showed increased susceptibility to UTI, as evidenced by higher bacterial CFU, more infiltrating neutrophils and severe pathological changes. Keratinocyte-derived chemokine increased in the kidney of WT mice but not in SP-A/D KO mice 24 h post-infection. Compared with control, the level of IL-17 was elevated in the kidney of infected WT and SP-A/D KO mice and the level of IL-17 was higher in the infected SP-A/D KO mice than in infected WT mice 24 and 48 h post-infection. The basal level of p38 MAPK phosphorylation in SP-A/D KO mice was higher than in WT mice. The phosphorylated p38 level was elevated in the kidney of WT mice post infection but not in SP-A/D KO mice. Furthermore, in vitro growth of uropathogenic E. coli was inhibited by SP-A and SP-D. We conclude that SP-A and SP-D function as mediators of innate immunity by inhibiting bacterial growth and modulating renal inflammation in part by regulating p38 MAPK-related pathway in murine UTI.
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Affiliation(s)
- Fengqi Hu
- Department of Surgery, SUNY Upstate Medical University, Syracuse, NY, USA Division of Nephrology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Guohua Ding
- Division of Nephrology, Renmin Hospital of Wuhan University, Wuhan, China
| | - Zhiyong Zhang
- Department of Surgery, SUNY Upstate Medical University, Syracuse, NY, USA
| | - Louis A Gatto
- Department of Biological Sciences, SUNY Cortland, Cortland, NY, USA
| | - Samuel Hawgood
- Department of Pediatrics and the Cardiovascular Research Institute, University of California, San Francisco, CA, USA
| | - Francis R Poulain
- Division of Neonatology, Department of Pediatrics, Children's Hospital, University of California Davis Medical Center, Davis, CA, USA
| | - Robert N Cooney
- Department of Surgery, SUNY Upstate Medical University, Syracuse, NY, USA
| | - Guirong Wang
- Department of Surgery, SUNY Upstate Medical University, Syracuse, NY, USA
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Yang W, Hu B, Wu W, Batra S, Blackburn MR, Alcorn JL, Fallon MB, Zhang J. Alveolar type II epithelial cell dysfunction in rat experimental hepatopulmonary syndrome (HPS). PLoS One 2014; 9:e113451. [PMID: 25419825 PMCID: PMC4242631 DOI: 10.1371/journal.pone.0113451] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Accepted: 10/24/2014] [Indexed: 12/18/2022] Open
Abstract
The hepatopulmonary syndrome (HPS) develops when pulmonary vasodilatation leads to abnormal gas exchange. However, in human HPS, restrictive ventilatory defects are also observed supporting that the alveolar epithelial compartment may also be affected. Alveolar type II epithelial cells (AT2) play a critical role in maintaining the alveolar compartment by producing four surfactant proteins (SPs, SP-A, SP-B, SP-C and SP-D) which also facilitate alveolar repair following injury. However, no studies have evaluated the alveolar epithelial compartment in experimental HPS. In this study, we evaluated the alveolar epithelial compartment and particularly AT2 cells in experimental HPS induced by common bile duct ligation (CBDL). We found a significant reduction in pulmonary SP production associated with increased apoptosis in AT2 cells after CBDL relative to controls. Lung morphology showed decreased mean alveolar chord length and lung volumes in CBDL animals that were not seen in control models supporting a selective reduction of alveolar airspace. Furthermore, we found that administration of TNF-α, the bile acid, chenodeoxycholic acid, and FXR nuclear receptor activation (GW4064) induced apoptosis and impaired SP-B and SP-C production in alveolar epithelial cells in vitro. These results imply that AT2 cell dysfunction occurs in experimental HPS and is associated with alterations in the alveolar epithelial compartment. Our findings support a novel contributing mechanism in experimental HPS that may be relevant to humans and a potential therapeutic target.
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Affiliation(s)
- Wenli Yang
- Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, The University of Texas Health Science Center at Houston, Houston, TX, United States of America
| | - Bingqian Hu
- Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, The University of Texas Health Science Center at Houston, Houston, TX, United States of America
| | - Wei Wu
- Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, The University of Texas Health Science Center at Houston, Houston, TX, United States of America
| | - Sachin Batra
- Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, The University of Texas Health Science Center at Houston, Houston, TX, United States of America
| | - Michael R. Blackburn
- Department of Biochemistry and Molecular Biology, The University of Texas Health Science Center at Houston, Houston, TX, United States of America
| | - Joseph L. Alcorn
- Division of Neonatology, Department of Pediatrics, The University of Texas Health Science Center at Houston, Houston, TX, United States of America
| | - Michael B. Fallon
- Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, The University of Texas Health Science Center at Houston, Houston, TX, United States of America
| | - Junlan Zhang
- Division of Gastroenterology, Hepatology and Nutrition, Department of Internal Medicine, The University of Texas Health Science Center at Houston, Houston, TX, United States of America
- * E-mail:
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