Parecoxib reduced ventilation induced lung injury in acute respiratory distress syndrome

Ventilator-induced lung injury in rat models: are they all equal in the race?

Risk of ventilator-induced lung injury (VILI) is an inevitable and precarious accompaniment of ventilator treatment in critically ill patients worldwide. It can both instigate and aggravate acute respiratory distress syndrome (ARDS) where the only prevention or treatment so far has been empirical approach of what is considered to be lung protective ventilator settings in an attempt to shield the lung tissues against the mechanical stress that unavoidably follows ventilator treatment. The weakened state of the patients limits clinical drug research and pushes for drug discovery in animal models. Mice and rats are often the choice of small animal model, representing about 95% of all laboratory animal studies, as their physiology can mimic that which is found in humans. Mice have been a more popular choice for ventilator studies but due to technical issues, there is some advantage gained in using rats as they are substantially larger. Inducing VILI and ARDS in these models can prove challenging and often the acute nature of the injury used to produce similar tissue damage as in humans does not necessarily fully reflect clinical reality. The aim of this review was to analyse and summarize methods of recent publications in the field, describing what approaches have been utilized to simulate these conditions, possibly identifying a common track enabling comparison of results between studies. However, the study shows a high variety of methods employed by researchers causing comparisons of results difficult and perhaps implying that a more standardized approach should be used.

Parecoxib sodium attenuates acute lung injury following burns by regulating M1/M2 macrophage polarization through the TLR4/NF-κB pathway

High temperature-induced burn injury often leads to an excessive inflammatory cascade resulting in multiple organ dysfunction syndrome, such as acute lung injury (ALI), in addition to skin tissue damage. As a specific COX2 inhibitor, parecoxib sodium suppresses the inflammatory response during burn injury. The effect of parecoxib sodium on ALI induced by burn injury and the associated molecular mechanism still need to be investigated. The role of parecoxib sodium in burn injury-induced ALI through the TLR4/NF-κB pathway was explored in the present study. A burn-induced ALI mouse model was constructed, and M1/M2 macrophages in lung tissue and markers involved in the TLR4/NF-κB signalling pathway were evaluated in bronchoalveolar lavage fluid (BALF) and MH-S mouse alveolar macrophages in vitro. The results indicated that parecoxib sodium attenuated lung injury after burn injury, decreased iNOS and TNF-α expression, increased IL-10 expression in BALF, and regulated the CD86-and CD206-mediated polarization of M1/M2 macrophages in lung tissue along with MH-S mouse alveolar macrophages. The effect of parecoxib sodium might be reversed by a TLR4 agonist. Overall, the results suggested that parecoxib sodium can regulate the polarization of M1/M2 macrophages through the TLR4/NF-κB pathway to attenuate ALI induced by skin burns.

Remission of organ failure in patients with predicted severe acute pancreatitis treated by somatostation, octreotide and cyclooxygenase-2 inhibitors

BACKGROUND

/Objectives: Persistent organ failure (OF) in severe acute pancreatitis (SAP) is caused by activation of cytokine cascades, resulting in inflammatory injury. Anti-inflammation may be helpful in OF remission in early SAP. To assess the efficacy of anti-inflammatory regimens for OF prevention and remission in patients with predicted SAP and display clinical doctors' acceptance of these strategies, we conducted this retrospective study in the real world.

METHODS

Clinical data of patients with predicted SAP from 2010 to 2017 were retrospectively reviewed. Cases were divided into conventional support (C), C+ somatostatin/octreotide (C + S/O), and C + S/O + Cyclooxygenase-2-inhibitors (C + S/O + COX-2-I). The occurrence of SAP, OF, changes of proportion for three strategies, length of hospital stay, meperidine injection, and cytokine levels were compared. The constituent ratios of the three schemes over eight years were evaluated.

RESULTS

A total of 580 cases (C = 124, C + S/O = 290, C + S/O + COX-2-I = 166) were included. The occurrences of SAP in the C + S/O (28.3 %) and C + S/O + COX-2-I (18.1 %) groups were significantly lower than that in C group (60.5 %, P < 0.001), mainly by reducing persistent respiratory failure (P < 0.001) and renal failure (P = 0.002). C + S/O and C + S/O + COX-2-I regimens significantly decreased new onset OF and enhanced OF amelioration within 48 h when compared with C treatment (P < 0.001) in patients with OF score <2 and ≥ 2 on admission, respectively. C + S/O and C + S/O + COX-2-I as compared with C group significantly decrease OF occurrences in a multivariate logistic regression analysis (P < 0.05).

CONCLUSIONS

Somatostatin or its analogs and cyclooxygenase-2 inhibitors are promising for OF prevention and remission in patients with predicted SAP. The acceptance of combined strategies in the real world has increased, and the occurrence of SAP has decreased annually.

Future directions in ventilator-induced lung injury associated cognitive impairment: a new sight

Mechanical ventilation is a widely used short-term life support technique, but an accompanying adverse consequence can be pulmonary damage which is called ventilator-induced lung injury (VILI). Mechanical ventilation can potentially affect the central nervous system and lead to long-term cognitive impairment. In recent years, many studies revealed that VILI, as a common lung injury, may be involved in the central pathogenesis of cognitive impairment by inducing hypoxia, inflammation, and changes in neural pathways. In addition, VILI has received attention in affecting the treatment of cognitive impairment and provides new insights into individualized therapy. The combination of lung protective ventilation and drug therapy can overcome the inevitable problems of poor prognosis from a new perspective. In this review, we summarized VILI and non-VILI factors as risk factors for cognitive impairment and concluded the latest mechanisms. Moreover, we retrospectively explored the role of improving VILI in cognitive impairment treatment. This work contributes to a better understanding of the pathogenesis of VILI-induced cognitive impairment and may provide future direction for the treatment and prognosis of cognitive impairment.

Pulmonary endothelium-targeted nanoassembly of indomethacin and superoxide dismutase relieves lung inflammation

Lung inflammation is an essential inducer of various diseases and is closely related to pulmonary-endothelium dysfunction. Herein, we propose a pulmonary endothelium-targeted codelivery system of anti-inflammatory indomethacin (IND) and antioxidant superoxide dismutase (SOD) by assembling the biopharmaceutical SOD onto the "vector" of rod-like pure IND crystals, followed by coating with anti-ICAM-1 antibody (Ab) for targeting endothelial cells. The codelivery system has a 237 nm diameter in length and extremely high drug loading of 39% IND and 2.3% SOD. Pharmacokinetics and biodistribution studies demonstrate the extended blood circulation and the strong pulmonary accumulation of the system after intravenous injection in the lipopolysaccharide (LPS)-induced inflammatory murine model. Particularly, the system allows a robust capacity to target pulmonary endothelium mostly due to the rod-shape and Ab coating effect. In vitro, the preparation shows the synergistic anti-inflammatory and antioxidant effects in LPS-activated endothelial cells. In vivo, the preparation exhibits superior pharmacodynamic efficacy revealed by significantly downregulating the inflammatory/oxidative stress markers, such as TNF-α, IL-6, COX-2, and reactive oxygen species (ROS), in the lungs. In conclusion, the codelivery system based on rod-like pure crystals could well target the pulmonary endothelium and effectively alleviate lung inflammation. The study offers a promising approach to combat pulmonary endothelium-associated diseases.

Significance of Pulmonary Endothelial Injury and the Role of Cyclooxygenase-2 and Prostanoid Signaling

The endothelium plays a key role in the dynamic balance of hemodynamic, humoral and inflammatory processes in the human body. Its central importance and the resulting therapeutic concepts are the subject of ongoing research efforts and form the basis for the treatment of numerous diseases. The pulmonary endothelium is an essential component for the gas exchange in humans. Pulmonary endothelial dysfunction has serious consequences for the oxygenation and the gas exchange in humans with the potential of consecutive multiple organ failure. Therefore, in this review, the dysfunction of the pulmonary endothel due to viral, bacterial, and fungal infections, ventilator-related injury, and aspiration is presented in a medical context. Selected aspects of the interaction of endothelial cells with primarily alveolar macrophages are reviewed in more detail. Elucidation of underlying causes and mechanisms of damage and repair may lead to new therapeutic approaches. Specific emphasis is placed on the processes leading to the induction of cyclooxygenase-2 and downstream prostanoid-based signaling pathways associated with this enzyme.

Parecoxib ameliorates renal toxicity and injury in sepsis-induced mouse model and LPS-induced HK-2 cells

Parecoxib is a selective COX-2-specific inhibitor, which has been demonstrated to inhibit sepsis-induced systemic inflammation, but its role in sepsis-induced acute kidney injury has not been studied. This study was designed to investigate the effects of Parecoxib on sepsis-induced acute kidney injury. In this study, the mice sepsis model was established using an internationally recognized cecal ligation and puncture (CLP). Hematoxylin-eosin staining was performed to examine kidney injury. Biochemical kit was used to detect the expression of BUN and Cre in serum, and ELISA was used to detect the expression of inflammatory factors in renal tissue. Tunel staining was used to detect tissue apoptosis. Furthermore, CCK-8 assay was used to detect the cell viability of HK-2 cells and RT-qPCR was used to detect the expression of LPS-induced inflammatory factors in HK-2 cells.TUNEL staining was used to detect the level of cell apoptosis. Finally, the expressions of COX-2, p-NF-kB P65, p-IKKβ, NF-kB P65, IKKβ, Kim1, NGAL, iNOS, VEGF, VEGFR2, CD31 and apoptosis-related proteins in renal tissues and HK-2 cells were detected by Western blot. We discovered that parecoxib could alleviate renal pathological changes, reduce renal function injury, and inhibit renal pathology to inhibit the release of inflammatory factors in renal tissue. Parecoxib inhibited sepsis induced microvascular damage and apoptosis in renal tissue. Parecoxib reduced the inflammation and apoptosis of renal tubular epithelial cells induced by LPS. Our data suggest that Parecoxib ameliorates sepsis-induced kidney injury, and may have potential as a novel therapeutic method for treating sepsis-induced kidney injury.

Mining the key genes for ventilator-induced lung injury using co-expression network analysis

Mechanical ventilation is extensively adopted in general anesthesia and respiratory failure management, but it can also induce ventilator-induced lung injury (VILI). Therefore, it is of great urgency to explore the mechanisms involved in the VILI pathogenesis, which might contribute to its future prevention and treatment. Four microarray datasets from the GEO database were selected in our investigation, and were subjected to the Weighted Gene Co-Expression Network Analysis (WGCNA) to identify the VILI-correlated gene modules. The limma package in R software was used to identify the differentially expressed genes (DEGs) between the VILI and control groups. WGCNA was constructed by merging the GSE9314, GSE9368, GSE11434 and GSE11662 datasets. A total of 49 co-expression network modules were determined as associated with VILI. The intersected genes between hub genes screened from DEGs for VILI and those identified using WGCNA were as follows: Tlr2, Hmox1, Serpine1, Mmp9, Il6, Il1b, Ptgs2, Fos and Atf3, which were determined to be key genes for VILI. Those key genes were validated by GSE86229 and quantitative PCR (qPCR) experiment to have significantly statistical difference in their expression between the VILI and control groups. In a nutshell, nine key genes with expression differences in VILI were screened by WGCNA by integrating multiple datasets.

Paracoxib Alleviates Ventilator-Induced Lung Injury Through Functional Modulation of Lung-Recruited CD11bloLy6Chi Monocytes

OBJECTIVE

Lung-recruited Ly6Chi monocytes had been shown to be involved in ventilator-induced lung injury (VILI). Our present study aimed to investigate whether the cyclooxygenase-2 (COX-2) inhibition modulates the function of lung-recruited Ly6Chi monocytes in a mouse model of VILI.

METHODS

Mice were exposed to lipopolysaccharide (LPS; 20 ng) intraperitoneally prior to injurious mechanical ventilation (Vt = 30 mL/kg, PEEP = 0 cmH2O). A subgroup of mice was treated with intravenous parecoxib (30 mg/kg), a COX-2 inhibitor, 1 h prior to ventilation. Control mice received saline and were not ventilated. At the end of the experiment, blood gas analysis was performed and lung tissue was collected for histological assessment. Flow cytometry was employed to quantify the different populations of lung monocytes/macrophages and their function. Isolated Ly6Chi cells were used to measure the intracellular concentrations of reactive oxygen species (ROS) and nitric oxide (NO) by fluorescent probes, and cytokine production by cytometric bead array.

RESULTS

Exposure to LPS and injurious ventilation was associated with severe lung histological damage, oxygenation impairment, and pulmonary edema; all of which were largely attenuated following the treatment of parecoxib. Furthermore, flow cytometry analysis revealed that parecoxib caused a reduction in the number of the lung-recruited CD11bloLy6Chi monocytes while there was no effect on tissue-resident CD64+ alveolar macrophages. In addition, the production of oxidative stress products (ROS, NO), MHC-II expression, and inflammatory cytokines in response to LPS and VILI in CD11bloLy6Chi monocytes was ameliorated by parecoxib.

CONCLUSION

Parecoxib-induced alleviation of oxidative stress and inflammation in lung-recruited Ly6Chi monocytes may partly explain the beneficial action of COX-2 inhibition in VILI.

Effects of Human Interleukin-10 on Ventilator-Associated Lung Injury in Rats

Ventilator-induced lung injury (VILI) is one of the most serious complications of mechanical ventilation (MV) and can increase the mortality of patients with acute respiratory distress syndrome (ARDS). This work aimed to test the hypothesis that the anti-inflammatory properties of human interleukin-10 (hIL-10) can reduce VILI. Thirty-six healthy male Sprague-Dawley rats were randomly assigned into three groups (n = 12) as follows: a control group, a VILI group, and a hIL-10 group. Lung function was evaluated by oxygenation index and pulmonary edema, and morphological changes associated with lung injury were assessed by HE staining and quantitative histological lung injury score. Malondialdehyde (MDA) and Superoxide dismutase (SOD) were measured, and the levels of various inflammatory cytokines were assessed in BALF and plasma. The oxygenation index in the VILI group decreased significantly relative to the control group and improved substantially in the hIL-10 group (P < 0.01). Compared to the control group, MDA production was stimulated (P < 0.01), and SOD activity rapidly declined (P < 0.01) in the VILI group. After hIL-10, MDA content was lower than that seen in the VILI group (P < 0.01), and SOD activity was enhanced (P < 0.01). The VILI group had the highest cytokine levels, compared to either the hIL-10 group or the control group (P < 0.05). High tidal volume MV can induce VILI. hIL-10 may regulate the inflammatory response in the lung tissue, improve lung tissue oxygenation, and inhibit oxidative stress, therefore reducing VILI in rats. These experiments reveal a potential new treatment option for VILI.

Cyclooxygenase-2 Activity Regulates Recruitment of VEGF-Secreting Ly6Chigh Monocytes in Ventilator-Induced Lung Injury

Mechanical ventilation is usually required for saving lives in critically ill patients; however, it can cause ventilator-induced lung injury (VILI). As VEGF-secreting Ly6C^high monocytes are involved in VILI pathogenesis, we investigated whether cyclooxygenase-2 (COX-2) activity regulates the recruitment of VEGF-secreting Ly6C^high monocytes during VILI. The clinically relevant two-hit mouse model of VILI, which involves the intravenous injection of lipopolysaccharide prior to high tidal volume (HTV)-mechanical ventilation, was used in this study. To investigate the role of COX-2 in the recruitment of VEGF-secreting Ly6C^high monocytes during VILI, celecoxib, which is a clinical COX-2 inhibitor, was administered 1 h prior to HTV-mechanical ventilation. Pulmonary vascular permeability and leakage, inflammatory leukocyte infiltration, and lung oxygenation levels were measured to assess the severity of VILI. HTV-mechanical ventilation significantly increased the recruitment of COX-2-expressing Ly6C^high, but not Ly6C^low, monocytes. Celecoxib significantly diminished the recruitment of Ly6C^high monocytes, attenuated the levels of VEGF and total protein in bronchoalveolar lavage fluid, and restored pulmonary oxygenation during VILI. Our findings demonstrate that COX-2 activity is important in the recruitment of VEGF-secreting Ly6C^high monocytes, which are involved in VILI pathogenesis, and indicate that the suppression of COX-2 activity might be a useful strategy in mitigating VILI.

Epigallocatechin gallate attenuates mitochondrial DNA-induced inflammatory damage in the development of ventilator-induced lung injury

OBJECTIVE

We aim to investigate the role of mitochondrial DNA (mtDNA), a novel endogenous pro-inflammatory cytokine, in the development of ventilator-induced lung injury (VILI). Moreover, the protective effect of epigallocatechin gallate (EGCG) on VILI through inhibiting local mtDNA release was examined.

METHODS

From March 2015 to March 2016, bronchoalveolar lavage fluid (BALF) from 36 patients with VILI and well-matched 36 patients without VILI after major surgery were consecutively collected. The expression levels of mtDNA and inflammatory cytokines in BALF were tested. SD rats were divided into five groups: control, low tidal volume (7 ml/kg) group, high tidal volume (HTV, 40 ml/kg) group, HTV+low dose EGCG and HTV+high dose EGCG groups. BALF were collected to examine the expression levels of mtDNA and several inflammatory cytokines and the lung tissue was harvested for pathological examinations. In addition, cyclic stretch cell culture was used and culture media was collected to analyze expressions of inflammatory cytokines. Administration of mtDNA in a rat model and in vitro cell culturing were used to confirm its pro-inflammatory properties in the development of inflammatory lung injury.

RESULTS

A Significant elevation of mtDNA was detected in BALF from patients with VILI (581 ± 193 vs. 311 ± 137, p < 0.05) and also in rats ventilated with HTV. EGCG could significantly inhibit HTV-induced local mtDNA release and attenuate the level of inflammatory lung injuries (reduced infiltration of local inflammatory cells, lower lung wet/dry ratio and expression levels of inflammatory cytokines). The beneficial effects of EGCG on preventing inflammatory lung injuries were in a concentration-dependent manner. Meanwhile, higher expression levels of mtDNA and inflammatory cytokines were observed in the media of cyclic stretched cell culture compared to those in the control group (p < 0.05). Furthermore, intra-tracheal administration of mtDNA in rats could lead to a marked increase of local inflammatory cytokines and subsequent inflammatory lung injuries (p < 0.05). And by adding mtDNA into the cell culture, higher level of inflammatory cytokines in the media was detected (p < 0.05). EGCG also showed preventive effects on inflammatory responses on a concentration-dependent manner (p < 0.05).

CONCLUSION

The increased expression level of mtDNA and subsequent inflammatory cytokines overproduction may play an important role in the development of VILI. EGCG may be a potential novel therapeutic candidate for protection against VILI by inhibiting the local release of mtDNA.