IL-6 knockout alleviates inflammatory response and improve acute lung injury via regulating macrophage polarization in sepsis

Abstract BackgroundSepsis is a fatal disease with a high rate of morbidity and mortality, during which acute lung injury is the earliest and most serious complication. Macrophage plays a crucial role in the initiation and progress of sepsis. This study meant to explore the effect of IL-6 knockout in CLP induced sepsis.MethodsIn this study, cecal ligation and puncture (CLP) was performed on wildtype and interleukin 6 (IL-6) knockout C57 mice. General condition and death rate of sepsis mice were observed. organ samples (lungs, livers, kidneys and hearts) and serum were collected for histology observation and inflammatory cytokine detection. Lung tissue injury detection were conducted via lung injury score, wet/dry ration and protein concentrations measurement of Bronchoalveolar lavage fluid (BALF). In in vivo studies, RAW264.7 macrophages were transfected with IL-6 specific siRNA and treated with LPS. After exposed to IL-6 specific siRNA and LPS, expression of inflammatory cytokines interleukin 1 (IL-1), tumor necrosis factor- (TNF-), IL-6 and interleukin 10 (IL-10) were detected by RT-qPCR, concentration of IL-1 and TNF- in culture supernatant were detected by ELISA and M1 and M2 markers were detected by western blot and flow cytometry.ResultsWe constructed CLP induced sepsis models and found that inhibition of IL-6 could improve general condition and death rate of sepsis mice. Mice in IL-6 knockout group display improved tissue damage, especially in the lung tissue. IL-6 knockout relieved inflammatory cytokines storm in both serum and bronchoalveolar lavage fluid while polarized macrophage to an anti-inflammatory M2 phenotype. In cell model, inhibition of IL-6 could alleviate LPS induced expression of inflammatory cytokines IL-1, TNF-, and IL-6 in macrophages. Western blot and Flow cytometry results indicated that expression of M1 markers (iNOS and CD86) in LPS stimulated macrophages were significantly declined while M2 (Arg-1 and CD206) were enhanced when expression of IL-6 was blocked.Conclusion Inhibition of IL-6 alleviated LPS induced inflammation and exerted protective effect in sepsis via regulating macrophage function and polarization.

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IL-6 knockout alleviates inflammatory response and improve acute lung injury via regulating macrophage polarization in sepsis

10.21203/rs.3.rs-618570/v1 ◽

2021 ◽

Author(s):

Jinxin Zhang ◽

Kuo Shen ◽

Jiangang Xie ◽

Shanshou Liu ◽

Xiaozhi Bai ◽

...

Keyword(s):

Flow Cytometry ◽

Acute Lung Injury ◽

Lung Injury ◽

Western Blot ◽

Bronchoalveolar Lavage ◽

Inflammatory Cytokines ◽

Death Rate ◽

Bronchoalveolar Lavage Fluid ◽

Lavage Fluid ◽

Tnf Α

Abstract Background Sepsis is a fatal disease with a high rate of morbidity and mortality, during which acute lung injury is the earliest and most serious complication. Macrophage plays a crucial role in the initiation and progress of sepsis. This study meant to explore the effect of IL-6 knockout in CLP induced sepsis. Methods In this study, cecal ligation and puncture (CLP) was performed on wildtype and interleukin 6 (IL-6) knockout C57 mice. General condition and death rate of sepsis mice were observed. organ samples (lungs, livers, kidneys and hearts) and serum were collected for histology observation and inflammatory cytokine detection. Lung tissue injury detection were conducted via lung injury score, wet/dry ration and protein concentrations measurement of Bronchoalveolar lavage fluid (BALF). In in vivo studies, RAW264.7 macrophages were transfected with IL-6 specific siRNA and treated with LPS. After exposed to IL-6 specific siRNA and LPS, expression of inflammatory cytokines interleukin 1 (IL-1), tumor necrosis factor-α (TNF-α), IL-6 and interleukin 10 (IL-10) were detected by RT-qPCR, concentration of IL-1 and TNF-α in culture supernatant were detected by ELISA and M1 and M2 markers were detected by western blot and flow cytometry. Results We constructed CLP induced sepsis models and found that inhibition of IL-6 could improve general condition and death rate of sepsis mice. Mice in IL-6 knockout group display improved tissue damage, especially in the lung tissue. IL-6 knockout relieved inflammatory cytokines storm in both serum and bronchoalveolar lavage fluid while polarized macrophage to an anti-inflammatory M2 phenotype. In cell model, inhibition of IL-6 could alleviate LPS induced expression of inflammatory cytokines IL-1, TNF-α, and IL-6 in macrophages. Western blot and Flow cytometry results indicated that expression of M1 markers (iNOS and CD86) in LPS stimulated macrophages were significantly declined while M2 (Arg-1 and CD206) were enhanced when expression of IL-6 was blocked. Conclusion Inhibition of IL-6 alleviated LPS induced inflammation and exerted protective effect in sepsis via regulating macrophage function and polarization.

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Optimization Of An LC-MS Approach For The Identification Of Acute Lung Injury (ALI) Metabolites In Bronchoalveolar Lavage Fluid (BALF)

10.1164/ajrccm-conference.2012.185.1_meetingabstracts.a2125 ◽

2012 ◽

Author(s):

Kathleen A. Stringer ◽

Charles Evans ◽

Chunhai Ruan ◽

Alla Karnovsky ◽

Theodore Standiford

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Bronchoalveolar Lavage ◽

Bronchoalveolar Lavage Fluid ◽

Lavage Fluid

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Metabolomic profile perturbations of serum, lung, bronchoalveolar lavage fluid, spleen and feces in LPS-induced acute lung injury rats based on HPLC-ESI-QTOF-MS

Analytical and Bioanalytical Chemistry ◽

10.1007/s00216-019-02357-1 ◽

2020 ◽

Vol 412 (5) ◽

pp. 1215-1234 ◽

Cited By ~ 2

Author(s):

Tianyang Wang ◽

Song Lin ◽

Ran Liu ◽

Hua Li ◽

Zihan Liu ◽

...

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Bronchoalveolar Lavage ◽

Bronchoalveolar Lavage Fluid ◽

Lavage Fluid ◽

Metabolomic Profile

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A rise of MMP-2 and MMP-9 in bronchoalveolar lavage fluid is associated with acute lung injury after cardiopulmonary bypass in a swine model

Perfusion ◽

10.1191/0267659103pf662oa ◽

2003 ◽

Vol 18 (2) ◽

pp. 107-113 ◽

Cited By ~ 12

Author(s):

Wolfgang Eichler ◽

J F Matthias Bechtel ◽

Jan Schumacher ◽

Johanna A Wermelt ◽

Karl-Friedrich Klotz ◽

...

Keyword(s):

Acute Lung Injury ◽

Cardiopulmonary Bypass ◽

Lung Injury ◽

Bronchoalveolar Lavage ◽

Bronchoalveolar Lavage Fluid ◽

Lavage Fluid ◽

Swine Model ◽

Tissue Samples ◽

Pulmonary Capillary ◽

A Prospective Study

Postoperative acute lung injury (ALI) contributes to the morbidity and mortality following cardiopulmonary bypass (CPB). To determine whether the presence of matrix metalloproteinases (MMPs) is associated with ALI after CPB, MMP-2 and MMP-9 activities in bronchoalveolar lavage fluid (BALF) were compared with parameters indicating impaired gas exchange. In a prospective study, 17 minipigs were subjected to CPB for 60 min. Before and at five and 180 min after CPB, MMP-2 and MMP-9 were assayed in BALF and the arterial-alveolar gradient of oxygen tension (AaDO2), the pulmonary capillary wedge pressure (PCWP) and the water content of lung tissue samples (Wt) were evaluated and compared with baseline values. MMP-2 and MMP-9 increased significantly 5 minutes (2.1- and 6.2-fold, respectively) and 180 minutes (3.4- and 14.3-fold, respectively) post-CPB. AaDO2 and Wt, but not PCWP, increased significantly 180 minutes after CPB and only AaDO2, but not PCWP or Wt, was significantly correlated with MMP-2 (r/0.66, p/0.006) and MMP-9 (r/0.62, p/0.01). In conclusion, high levels of MMP-2 and MMP-9 in the pulmonary compartment are associated with ALI after CPB.

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Dynamic mechanical consequences of deep inflation in mice depend on type and degree of lung injury

Journal of Applied Physiology ◽

10.1152/japplphysiol.00270.2003 ◽

2004 ◽

Vol 96 (1) ◽

pp. 293-300 ◽

Cited By ~ 50

Author(s):

Gilman Allen ◽

Jason H. T. Bates

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Bronchoalveolar Lavage ◽

Bronchoalveolar Lavage Fluid ◽

Fluid Pressure ◽

Lavage Fluid ◽

Forced Oscillations ◽

Positive End Expiratory Pressure ◽

Reduced Pressure ◽

Volume Curve

In a previous study (Allen G, Lundblad LK, Parsons P, and Bates JH. J Appl Physiol 93: 1709-1715 , 2002), our laboratory used deep inflations (DI) in mice to show that recruitment of closed lung units can be a very transient phenomenon in lung injury. The purpose of this study was to investigate how this transience of lung recruitment depends on the nature and degree of acute lung injury. Mice were administered 50 μl of either saline ( n = 8), 0.01 M ( n = 9) or 0.025 M ( n = 8) hydrochloric acid, or 50 μg ( n = 10) or 150 μg ( n = 6) of LPS and were mechanically ventilated 24-48 h later. At various levels of positive end-expiratory pressure, two DIs were delivered, and forced oscillations were used to obtain a measure of lung stiffness ( H) periodically over 7 min. After LPS exposure, pressure-volume curve hysteresis and recovery in H after DI were no different from saline-exposed controls despite 500 times more neutrophils in bronchoalveolar lavage fluid. Pressure-volume hysteresis and recovery in H were increased in acid-exposed mice ( P < 0.001) and were correlated with bronchoalveolar lavage fluid protein content ( R = 0.81). Positive end-expiratory pressure reduced recovery in H in all groups ( P < 0.01) but reduced pressure-volume hysteresis in the acid-injured groups only ( P < 0.001). We conclude that the effects of DIs in acute lung injury depend on the degree of lung injury but only to the extent that this injury reflects a disruption of the air-liquid interface.

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Increased claudin-3, -4 and -18 levels in bronchoalveolar lavage fluid reflect severity of acute lung injury

Respirology ◽

10.1111/resp.12034 ◽

2013 ◽

Vol 18 (4) ◽

pp. 643-651 ◽

Cited By ~ 11

Author(s):

Wenting Jin ◽

Linyi Rong ◽

Yinkun Liu ◽

Yuanlin Song ◽

Yan Li ◽

...

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Bronchoalveolar Lavage ◽

Bronchoalveolar Lavage Fluid ◽

Lavage Fluid

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A Metabolomic Approach to the Pathogenesis of Ventilator-induced Lung Injury

Anesthesiology ◽

10.1097/aln.0000000000000074 ◽

2014 ◽

Vol 120 (3) ◽

pp. 694-702 ◽

Cited By ~ 15

Author(s):

José L. Izquierdo-García ◽

Shama Naz ◽

Nicolás Nin ◽

Yeny Rojas ◽

Marcela Erazo ◽

...

Keyword(s):

Lung Injury ◽

Bronchoalveolar Lavage ◽

Tidal Volume ◽

Lung Tissue ◽

Metabolic Profiling ◽

Metabolic Profile ◽

Bronchoalveolar Lavage Fluid ◽

Lavage Fluid ◽

Positive End Expiratory Pressure ◽

Ventilator Induced Lung Injury

Abstract Background: Global metabolic profiling using quantitative nuclear magnetic resonance spectroscopy (MRS) and mass spectrometry (MS) is useful for biomarker discovery. The objective of this study was to discover biomarkers of acute lung injury induced by mechanical ventilation (ventilator-induced lung injury [VILI]), by using MRS and MS. Methods: Male Sprague–Dawley rats were subjected to two ventilatory strategies for 2.5 h: tidal volume 9 ml/kg, positive end-expiratory pressure 5 cm H2O (control, n = 14); and tidal volume 25 ml/kg and positive end-expiratory pressure 0 cm H2O (VILI, n = 10). Lung tissue, bronchoalveolar lavage fluid, and serum spectra were obtained by high-resolution magic angle spinning and 1H-MRS. Serum spectra were acquired by high-performance liquid chromatography coupled to quadupole-time of flight MS. Principal component and partial least squares analyses were performed. Results: Metabolic profiling discriminated characteristics between control and VILI animals. As compared with the controls, animals with VILI showed by MRS higher concentrations of lactate and lower concentration of glucose and glycine in lung tissue, accompanied by increased levels of glucose, lactate, acetate, 3-hydroxybutyrate, and creatine in bronchoalveolar lavage fluid. In serum, increased levels of phosphatidylcholine, oleamide, sphinganine, hexadecenal and lysine, and decreased levels of lyso-phosphatidylcholine and sphingosine were identified by MS. Conclusions: This pilot study suggests that VILI is characterized by a particular metabolic profile that can be identified by MRS and MS. The metabolic profile, though preliminary and pending confirmation in larger data sets, suggests alterations in energy and membrane lipids. SUPPLEMENTAL DIGITAL CONTENT IS AVAILABLE IN THE TEXT

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Hypothermia Induced by Adenosine5′-Monophosphate Attenuates Acute Lung Injury Induced by LPS in Rats

Mediators of Inflammation ◽

10.1155/2012/459617 ◽

2012 ◽

Vol 2012 ◽

pp. 1-7 ◽

Cited By ~ 7

Author(s):

Zhimin Miao ◽

Shulai Lu ◽

Na Du ◽

Weiting Guo ◽

Jidong Zhang ◽

...

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Bronchoalveolar Lavage ◽

Inflammatory Cytokine ◽

Bronchoalveolar Lavage Fluid ◽

Lavage Fluid ◽

Acute Injury ◽

Pathological Changes ◽

Inflammatory Reactions ◽

Cytokine Levels

We have built a rat’s model to investigate whether the hypothermia induced by adenosine 5′-monophosphate (5′-AMP) (AIH) could attenuate acute lung injury induced by LPS in rats. We detected the inflammatory cytokine levels in the plasma and bronchoalveolar lavage fluid samples, and we analyzed the pathological changes in the lungs. We have found that AIH can effectively inhibit acute inflammatory reactions and protect the lung from acute injury induced by LPS in rats.

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