Molecular mechanisms of paraquat-induced acute lung injury: a current review

Edaravone: A Possible Treatment for Acute Lung Injury

Despite technological advances in science and medicine, acute lung injury (ALI) is still associated with high mortality rates in the ICU. Therefore, finding novel drugs and treatment approaches is crucial to preventing ALI. Drug repurposing is a common practice in clinical research, primarily for drugs that have previously received approval for use in patients, to investigate novel uses of drugs and therapies. One such medication is edaravone, which is a highly effective free-radical scavenger that also has anti-inflammatory, anti-apoptotic, antioxidant, and anti-fibrotic effects. Both basic and clinical studies have shown that edaravone can treat different types of lung injury through its distinct properties. Edaravone exhibits significant protective benefits and holds promising clinical treatment potential for ALI caused by diverse factors, thereby offering a novel approach to treating ALI. This study aims to provide new insights and treatment options for ALI by reviewing both basic and clinical research on the use of edaravone. The focus is on evaluating the effectiveness of edaravone in treating ALI caused by various factors.

The preventive effectiveness of Crocus sativus extract in treating lung injuries caused by inhaled paraquat in rats

ETHNOPHARMACOLOGICAL RELEVANCE

The herbicide paraquat (PQ) is highly toxic, capable of inducing severe lung inflammation and oxidative stress, resulting in lung fibrosis and respiratory failure. Previous research has demonstrated a range of pharmacological effects associated with Crocus sativus. L (Cs) through its anti-inflammatory, antioxidant and immunomodulatory properties. Pharmacological studies support the widespread use of Cs in traditional medicine to treat respiratory disorders such as coughs and asthma.

AIM OF STUDY

This study aimed to investigate the preventive impact of Cs extract and pioglitazone (Pio) on lung inflammation, oxidative stress, pathological alterations, and tracheal reactivity induced by inhaled PQ in rats as compared to dexamethasone (Dexa).

METHODS

The control (Ctrl) group of rats was administered with saline aerosol, while the remaining six groups received PQ aerosol eight times every other day. The six PQ exposure groups were treated daily during the exposure period to PQ with either; saline alone, low dose Cs, High dose Cs, Pio alone, Pio combined with low dose Cs, or Dexa of 16 days.

RESULTS

In the PQ group, the levels of superoxide dismutase (SOD), catalase (CAT), and thiol in the bronchoalveolar lavage fluid (BALF) were declined whereas, the levels of MDA, total and differential WBC, and lung tissue levels of tumor necrosis factor (TNF-α) and Interleukin 10 (IL-10), tracheal responsiveness (TR) to methacholine and lung pathological changes were enhanced. The measured variables showed significant improvement in all treated groups, except for a few variables in Cs (L). The combined Cs (L) + Pio showed higher effects than Cs (L) and Pio alone. For all comparisons, p values were <0.05 to <0.001.

CONCLUSIONS

The results showed preventive effect of Cs comparable to that of Dexa and the potential additive preventive capabilities of the Cs and Pio indicate that the involvement of the PPARγ receptor is implicated in the effects induced by Cs.

Prognostic Value of the Average Lung CT Number in Patients with Acute Paraquat Poisoning

Objective

The chest computed tomography (CT) examination is an important clinical examination in the diagnosis and monitoring of paraquat- (PQ-) induced lung injury. The aim of this study was to explore the prognostic value of the average lung CT number acquired by quantitative CT techniques in patients with acute paraquat poisoning in the early stages of the disease.

Methods

46 patients who suffered from acute PQ poisoning in the emergency department of the Nanjing Drum Tower Hospital from January 2015 to June 2020 were enrolled in the present study. The patients were divided into survival group (n = 21) and nonsurvival group (n = 25). Clinical data were collected from subjects who met the inclusion criteria, including general information, personal disease history, and laboratory test indicators. The average lung CT numbers of each patient were obtained by quantitative CT techniques. Receiver operating characteristic (ROC) analysis was conducted to assess the prognostic value of average lung CT number in patients with acute paraquat poisoning.

Results

The average CT numbers of the middle-lung, lower-lung, and whole lung fields in the nonsurvival group were significantly higher than those of the survival group (p < 0.0001). However, the upper-lung field was not significantly different between the two groups (p = 0.7765). The AUCs of different levels ranged from 0.554 to 0.977, among which the lower-lung field presented the largest AUC of 0.977 (95% CI: 0.943∼1; cut-off value: -702Hu; sensitivity 96%; specificity, 90.5%; YI: 0.865), followed by the whole lung field 0.914 (95% CI: 0.830∼0.999; cut-off value: -727Hu; sensitivity 76%; specificity, 95.2%; YI: 0.712) and the middle-lung field 0.87 (95% CI: 0.768∼0.971; cut-off value: -779Hu; sensitivity 80%; specificity, 85.7%; YI: 0.657).

Conclusion

The present study indicated that the average lung CT number could be used to evaluate the relationship between the severity of PQ-induced lung injury and prognosis, especially in the lower-lung field. However, further research is needed to draw a clear conclusion.

A systematic review of the research progress of traditional Chinese medicine against pulmonary fibrosis: from a pharmacological perspective

Pulmonary fibrosis is a chronic progressive interstitial lung disease caused by a variety of etiologies. The disease can eventually lead to irreversible damage to the lung tissue structure, severely affecting respiratory function and posing a serious threat to human health. Currently, glucocorticoids and immunosuppressants are the main drugs used in the clinical treatment of pulmonary fibrosis, but their efficacy is limited and they can cause serious adverse effects. Traditional Chinese medicines have important research value and potential for clinical application in anti-pulmonary fibrosis. In recent years, more and more scientific researches have been conducted on the use of traditional Chinese medicine to improve or reduce pulmonary fibrosis, and some important breakthroughs have been made. This review paper systematically summarized the research progress of pharmacological mechanism of traditional Chinese medicines and their active compounds in improving or reducing pulmonary fibrosis. We conducted a systematic search in several main scientific databases, including PubMed, Web of Science, and Google Scholar, using keywords such as idiopathic pulmonary fibrosis, pulmonary fibrosis, interstitial pneumonia, natural products, herbal medicine, and therapeutic methods. Ultimately, 252 articles were included and systematically evaluated in this analysis. The anti-fibrotic mechanisms of these traditional Chinese medicine studies can be roughly categorized into 5 main aspects, including inhibition of epithelial-mesenchymal transition, anti-inflammatory and antioxidant effects, improvement of extracellular matrix deposition, mediation of apoptosis and autophagy, and inhibition of endoplasmic reticulum stress. The purpose of this article is to provide pharmaceutical researchers with information on the progress of scientific research on improving or reducing Pulmonary fibrosis with traditional Chinese medicine, and to provide reference for further pharmacological research.

Nitric oxide-mediated the therapeutic properties of induced pluripotent stem cell for paraquat-induced acute lung injury

The mortality rate associated with acute lung injury (ALI) and its severe form, acute respiratory distress syndrome, is high. Induced pluripotent stem cell (iPSC) therapy is a potential treatment method for ALI, but its therapeutic efficacy is limited in injured lungs. Nitric oxide (NO) has various physiological actions. The current study investigated the effect of iPSCs pretreated with NO donors in paraquat (PQ)-induced ALI mouse model. Male C57BL/6 mice were intraperitoneally injected with PQ, followed by infusion of phosphate-buffered saline, iPSCs, L-arginine pretreated iPSCs, or Nitro-L-arginine methylester (L-NAME) pretreated iPSCs through the tail veins. Histopathological changes, pulmonary microvascular permeability, and inflammatory cytokine levels were analyzed after 3 or 28 d. The effects on iPSC proliferation, migration, and adhesion were evaluated in vitro. More L-arginine-pretreated iPSCs were selectively trafficked into the injured pulmonary tissue of mice with LPS-induced ALI, drastically diminishing the histopathologic changes and inflammatory cytokine levels (IL-1β and IL-6). There was also markedly improved pulmonary microvascular permeability and pulmonary function. The NO inhibitor abolished the protective effects of iPSCs. In addition, the ability of L-arginine to promote the proliferation and migration of iPSCs was decreased by L-NAME pretreatment, suggesting that NO might mediate the therapeutic benefits of iPSC. The improvement of the iPSC physiological changes by the endogenous gaseous molecule NO reduces lung injury severity. L-Arginine represents a pharmacologically important strategy for enhancing the therapeutic potential of iPSCs.

Evaluation of nano-curcumin against inhaled paraquat-induced lung injury in rats

BACKGROUND

Acute lung injury (ALI) remains a significant source of morbidity and mortality in critically ill patients and currently there is no efficient therapy for this condition. The aim of this research was to evaluate the protective activity of nano-curcumin (nano-CU) as a natural anti-inflammatory and antioxidant agent, against inhaled paraquat (PQ)-induced lung injury.

METHODS

One group of rats was exposed to saline (control group, Ctrl) and six groups to PQ aerosol (54 mg/m³ on alternate days 8 times, each time for 30 min) treated with drinking water alone (group PQ), 2 and 8 mg/kg nano-CU (nano + CU(L) and nano + CU(H)), 5 mg/kg pioglitazone (PIO), nano-CU(L) + PIO or 0.03 mg/kg dexamethasone (Dexa) for 16 days after PQ exposure period. PIO and Dexa were intraperitoneal (ip) injected and nano-CU was administered orally (po), (6 rats in each group).

RESULTS

In the PQ group, total and differential WBC counts, malondialdehyde (MDA) in the bronchoalveolar lavage fluid (BALF), interferon gamma (INF-γ) and interleukin 10 (IL-10) levels in the lung tissues, lung pathological changes, and tracheal responsiveness were increased but the BALF thiol, catalase (CAT) and superoxide dismutase (SOD) levels were reduced. In treated groups with nano-CU(H) and PIO + nano-CU(L), all measured variables, in Dexa and nano-CU(L) treated groups, most variables and in the PIO group only a few variables were improved. The improvement of most variables in the PIO + nano-CU(L) group was significantly higher than in the PIO and nano-CU(L) groups alone.

CONCLUSIONS

Nano-CU ameliorated lung damage induced by inhaled PQ similar to dexa and a synergic effect between nano-CU and PIO was observed, suggesting, a possible PPAR-γ receptor-mediated effect of curcumin.

HIF-1α promotes paraquat induced acute lung injury and implicates a role NF-κB and Rac2 activity

Paraquat (PQ) is a bipyridine herbicide and oral exposure is the main way of PQ exposure with a very high mortality. At present, it is believed that large number of oxygen free radicals are generated and cause lipid peroxidation of tissue and organ cell membranes after PQ is absorbed. PQ exposure could cause multiple organ dysfunction, among which acute lung injury is the most common and most serious. However, its specific mechanism is still unclear. In this study, the C57BL/6J mouse (alveolar epithelial cell-specific knockout HIF-1α) model of acute lung injury (40 mg/kg PQ) at several time pointes and a model of acute type II alveolar epithelial cell (A549, 800 μM PQ) injury constructed. The oxidative stress (ROS, MDA) and inflammatory response (IL-1β, IL-6, TNF-α) were significantly inhibited in the alveolar epithelial cell-specific knockout of HIF-1α mice and siRNA technology to inhibit HIF-1α in alveolar epithelial cells. Further proteomic analysis showed that the expression of Rac2 protein, which is closely related to oxidative stress, was significantly increased after PQ exposure. And the inhibition of Rac2 expression in vitro significantly alleviated PQ-induced oxidative stress and inflammatory response. The expression of Rac2 protein was regulated by HIF-1α. The above suggests that HIF-1α may promote oxidative stress and inflammatory response in alveolar epithelial cells by regulating the expression of Rac2, and then participate in the promotion of PQ exposure-induced acute lung injury.

Cannabinoid Analogue WIN 55212-2 Protects Paraquat-Induced Lung Injury and Enhances Macrophage M2 Polarization

WIN 55212-2 is an endocannabinoids analogue that has been reported to have anti-inflammatory and anti-fibrosis effects on different models. In this study, we investigated the protective effects of WIN 55212-2 on paraquat (PQ)-induced poison on mice especially on lung injury. Mice were administrated with different dose of PQ and thereafter treated with 0.2 mg/kg or 1 mg/kg WIN 55212-2. The survival of mice was recorded during 4 weeks of observation. Twenty-eight days after PQ treatment, the cell population and inflammatory factors IL-6, IL-10, and TNF-α were measured in bronchoalveolar lavage fluid (BALF). Pulmonary fibrosis was evaluated by Masson staining. Our results showed that WIN 55212-2 treatment reduced PQ-induced mortality of mice in a dose dependent manner. It decreased the number of inflammation-associated cells, as well as the level of pro-inflammatory factors in BALF (P < 0.05). WIN 55212-2 increased M2 cells in BALF (P < 0.05), improved the lung histology, reduced fibrosis formation, and decreased TGF-β, α-SMA and PDGFRa expression. The protective effects of WIN 55212-2 on PQ-induced lung injury and fibrosis were associated with an increase inM2 cells and increased expressions of IL-10, CD163, and CD206, suggesting that polarization of M2 macrophages may be involved in WIN 55212-2 protective effects on PQ-induced lung injury.

Risk factors and optimal predictive scoring system of mortality for children with acute paraquat poisoning

BACKGROUND

There is no suitable scoring system that can be used to predict mortality in children with acute paraquat intoxication (APP).

AIM

To optimize a predictive scoring system for mortality in children with APP.

METHODS

A total of 113 children with APP from January 1, 2010 to January 1, 2020 were enrolled in this study. These patients were divided into survivors and non-survivors. We compared the clinical characteristics between the two groups and analyzed the independent prognostic risk factors. The survival rates of patients with different values of the pediatric critical illness score (PCIS) were assessed using kaplan-meier survival analysis. The best scoring system was established by using the area under the receiver operating characteristic curve analysis.

RESULTS

The overall mortality rate was 23.4%. All non-survivors died within 20 days; 48.1% (13/27) died within 3 days, and 70.3% (19/27) died within 7 days. Compared to survivors, the non-survivors were older, had higher white blood cell count, alanine aminotransferase (ALT), aspartate aminotransferase, serum creatinine, blood urea nitrogen, glucose, and pediatric early warning score, and had lower platelet count, albumin, Serum sodium (Na⁺) and PCIS. ALT and PCIS were the independent prognostic risk factors for children with APP. The survival rate of children classified as extremely critical patients (100%) was lower than that of children classified as critical (60%) or noncritical (6.7%) patients. The specificity of ALT was high (96.51%), but the sensitivity was low (59.26%). The sensitivity and specificity of ALT combined with PCIS were high, 92.59% and 87.21%, respectively. The difference in mortality was significantly higher for ALT combined with PCIS (area under the receiver operating characteristic: 0.937; 95%CI: 0.875-0.974; P < 0.05).

CONCLUSION

In our study, ALT and PCIS were independent prognostic risk factors for children with APP. ALT combined with PCIS is an optimal predictive mortality scoring system for children with APP.

Pulmonary histopathology in fatal paraquat poisoning

Paraquat is a potent herbicide widely used in the Indian agriculture industry. Human fatality due to paraquat poisoning is not uncommon in this country. The primary effect of paraquat is on the lungs, and the resultant pulmonary damage leads to the patient's demise. There is a high mortality rate in paraquat poisoning as the treatment is usually supportive with no known antidote. There are limited human studies that have observed the histopathological changes in lungs in paraquat poisoning. The authors have discussed the time-related histopathological changes in lungs in paraquat poisoning on autopsy subjects. The role of anticoagulants and fibrinolytic agents in the treatment of this poisoning has also been discussed.

Resolvin D1, therapeutic target in acute respiratory distress syndrome

Acute lung injury (ALI), or its more severe form, acute respiratory distress syndrome (ARDS), is a disease with high mortality and is a serious challenge facing the World Health Organization because there is no specific treatment. The excessive and prolonged immune response is the hallmark of this disorder, so modulating and regulating inflammation plays an important role in its prevention and treatment. Resolvin D1 (RvD1) as a specialized pro-resolving mediator has the potential to suppress the expression of inflammatory cytokines and to facilitate the production of antioxidant proteins by stimulating lipoxin A4 receptor/formyl peptide receptor 2 (ALX/FPR2). These changes limit the invasion of immune cells into the lung tissue, inhibit coagulation, and enhance cell protection against oxidative stress (OS). In particular, this biomolecule reduces the generation of reactive oxygen species (ROS) by blocking the activation of inflammatory transcription factors, especially nuclear factor-κB (NF-κB), and accelerating the synthesis of antioxidant compounds such as heme oxygenase 1 (HO-1) and superoxide dismutase (SOD). Therefore, the destruction and dysfunction of important cell components such as cytoplasmic membrane, mitochondria, Na+/k + adenosine triphosphatase (ATPase) and proteins involved in the phagocytic activity of scavenger macrophages are attenuated. Numerous studies on the effect of RvD1 over inflammation using animal models revealed that Rvs have both anti-inflammatory and pro-resolving capabilities and therefore, might have potential therapeutic value in treating ALI. Here, we review the current knowledge on the classification, biosynthesis, receptors, mechanisms of action, and role of Rvs in ALI/ARDS.

Evaluation of the hepatoprotective effects of curcumin and nanocurcumin against paraquat-induced liver injury in rats: Modulation of oxidative stress and Nrf2 pathway

Paraquat (PQ) is a widely used herbicide all over the world, which is highly toxic for animals and humans. Its cytotoxicity is based on reactive radical generation. The aim of this study is to evaluate and compare the hepatoprotective effects of curcumin and nanocurcumin against liver damage caused by sub-acute exposure with PQ via modulation of oxidative stress and genes expression of nuclear factor erythroid 2-related factor 2 (Nrf2) pathway. Rats were exposed to PQ (5 mg/kg/day, orally) + curcumin or nanocurcumin (100 mg/kg/day, orally) for 7 days. Then rats were anesthetized and serum and liver samples were collected. Next, serum enzymatic activities, liver histopathology, oxidative stress, and expression of genes involved in Nrf2 signaling pathway were assessed by biochemical and enzyme-linked immunosorbent assay methods, hematoxylin and eosin staining, and real-time polymerase chain reaction analysis. PQ significantly increased malondialdehyde, alanine transaminase, aspartate aminotransferase, alkaline phosphatase levels, and Kelch-like ECH-associated protein 1 gene expression and also decreased total antioxidant capacity, total thiol group levels, Glutathione S-transferases, heme oxygenase 1, Nrf2, and NAD(P)H:quinone oxidoreductase 1 genes expression, causing histological damages to liver tissue. These changes were significantly modulated by curcumin and nanocurcumin treatments. Our findings showed that nanocurcumin had better hepatoprotective effect than curcumin in liver damage after PQ exposure most likely through modulation of oxidative stress and genes expression of Nrf2 pathway.

Thal protects against paraquat-induced lung injury through a microRNA-141/HDAC6/IκBα-NF-κB axis in rat and cell models

The protective functions of thalidomide in paraquat (PQ)-induced injury have been reported. But the mechanisms remain largely unknown. In this research, a PQ-treated rat model was established and further treated with thalidomide. Oedema and pathological changes, oxidative stress, inflammation, fibrosis and cell apoptosis in rat lungs were detected. A PQ-treated RLE-6TN cell model was constructed, and the viability and apoptosis rate of cells were measured. Differentially expressed microRNAs (miRNAs) after thalidomide administration were screened out. Binding relationship between miR-141 and histone deacetylase 6 (HDAC6) was validated. Altered expression of miR-141 and HDAC6 was introduced to identify their involvements in thalidomide-mediated events. Consequently, thalidomide administration alone exerted no damage to rat lungs; in addition it reduced PQ-induced oedema. The oxidative stress, inflammation and cell apoptosis in rat lungs were reduced by thalidomide. In RLE-6TN cells, thalidomide increased cell viability and decreased apoptosis. miR-141 was responsible for thalidomide-mediated protective events by targeting HDAC6. Overexpression of HDAC6 blocked the protection of thalidomide against PQ-induced injury via activating the IkBα-NF-κB signalling pathway. Collectively, this study evidenced that thalidomide protects lung tissues from PQ-induced injury through a miR-141/HDAC6/IkBα-NF-κB axis.

Modeling paraquat-induced lung fibrosis in C. elegans reveals KRIT1 as a key regulator of collagen gene transcription

Paraquat poisoning causes lung fibrosis, which often results in long-term pulmonary dysfunction. Lung fibrosis has been attributed to collagens accumulation, but the underlying regulatory pathway remains unclear. Here we use the genetically tractable C. elegans as a model to study collagen gene transcription in response to paraquat. We find that paraquat robustly up-regulates collagen gene transcription, which is dependent on KRI-1, a poorly studied protein homologous to human KRIT1/CCM1. KRI-1 knockdown prevents paraquat from activating the oxidative stress response transcription factor SKN-1/Nrf2, resulting in reduced collagen transcription and increased paraquat sensitivity. Using human lung fibroblasts (MRC-5), we confirm that both KRIT1 and Nrf2 are required for collagen transcription in response to paraquat. Nrf2 hyper-activation by KEAP1 knockdown bypasses KRIT1 to up-regulate collagen transcription. Our findings on the regulation of collagen gene transcription by paraquat could suggest potential strategies to treat pulmonary fibrosis caused by paraquat poisoning.

Role of epithelial-to-mesenchymal transition in the pulmonary fibrosis induced by paraquat in rats

BACKGROUND

This study aims to explore the characteristics of the epithelial-to-mesenchymal transition (EMT) process and its underlying molecular mechanisms in the period of paraquat (PQ)-induced pulmonary fibrosis (PF).

METHODS

Picrosirius red staining and collagen volume fraction were utilized to evaluate the pathological changes of PQ-induced PF in rats. Immunohistochemistry, Western blot, and real-time reverse transcriptase-polymerase chain reaction (RT-PCR) were used to measure the protein and gene expression of EMT markers, EMT-associated transcription factors, and regulators of EMT-related pathways, respectively.

RESULTS

The collagen deposition in the alveolar septum and increased PF markers were characteristics of pathological changes in PQ-induced PF, reached a peak on day 14 after PQ poisoning, and then decreased on day 21. The protein and gene expression of the fibrosis marker, EMT markers, transcription factors, and regulators of EMT-related signaling pathways significantly increased at different time points after PQ poisoning compared with corresponding controls (P<0.05), and most of them reached a peak on day 14, followed by a decrease on day 21. The gene expression of EMT markers was significantly correlated with PF markers, transcription factors, and regulators of EMT-related signaling pathways (P<0.05). The mRNA expression of transcription factors was significantly correlated with that of TGF-β1 and Smad2 (P<0.05 or P<0.01), instead of Wnt2 and β-catenin (P>0.05).

CONCLUSIONS

EMT process plays a role in the PQ-induced PF, in which most PF and EMT markers have a peak phenomenon, and its underlying molecular mechanisms might be determined by further studies.

Analysis of microRNA expression profiling during paraquat-induced injury of murine lung alveolar epithelial cells

Paraquat (PQ) as a non-selective heterocyclic herbicide, has been applied worldwide for over a few decades. But PQ is very harmful to humans and rodents. The lung is the main target organ of PQ poisoning. It is an important event that lung epithelial cells are injured during PQ-induced acute lung injury and pulmonary fibrosis. As a regulator of mRNA expression, microRNA (miRNA) may play an important role in the progress. Our study was to investigate the mechanisms of PQ-induced injury of pulmonary epithelial cells through analyzing the profiling of miRNAs and their target genes. As a result, 11 differentially expressed miRNAs were screened, including 1 upregulated miRNA and 10 downregulated miRNAs in PQ-treated murine lung alveolar epithelial cells (MLE-12 cells). The bioinformatic analyses suggested that the target genes of these miRNAs were involved in mitochondrial apoptosis pathway and DNA methylation, and participated in the regulation of PI3K-Akt, mTOR, RAS, TNF, MAPK and other signal pathways which related to oxidative stress and apoptosis. This indicated that miRNAs were an important regulator of oxidative stress and apoptosis during PQ-induced injury of murine lung alveolar epithelial cells. The findings would deepen our understanding of the mechanisms of PQ-induced pulmonary injury and might provide new treatment targets for this disease.

Klotho Alleviates Lung Injury Caused by Paraquat via Suppressing ROS/P38 MAPK-Regulated Inflammatory Responses and Apoptosis

Acute lung injury (ALI) induced by paraquat (PQ) progresses rapidly with high mortality; however, there is no effective treatment, and the specific mechanism is not well understood. The antiaging protein klotho (KL) has multiple functions and exerts significant influences on various pathophysiological processes. This work evaluated the impact of KL on PQ-induced ALI and investigated its underlying mechanisms. As for in vivo research, C57BL/6 mice were treated with PQ (30 mg/kg) intraperitoneal (IP) injection to create a toxicity model of ALI (PQ group). The mice were divided into control group, KL group, PQ group, and PQ+KL group. For in vitro experiment, A549 cells were incubated with or without KL and then treated in the presence or absence of PQ for 24 h. In vivo result indicated that KL reduced the mortality, reduced IL-1β and IL-6 in the bronchoalveolar lavage fluid (BALF), attenuated ALI, and decreased apoptosis in situ. In vitro result revealed that KL significantly improved cell viability, reduced the levels of IL-1β and IL-6 in culture supernatants, suppressed cell apoptosis, inhibited caspase-3 activation, and enhanced mitochondrial membrane potential (ΔΨm) after PQ treatment. Besides, KL effectively abated reactive oxygen species (ROS) production, improved GSH content, and lowered lipid peroxidation in PQ-exposed A549 cells. Further experiments indicated that phosphorylated JNK and P38 MAPK was increased after PQ treatment; however, KL pretreatment could significantly lower the phosphorylation of P38 MAPK. Suppression of P38 MAPK improved cell viability, alleviated inflammatory response, and reduced apoptosis-related signals; however, it had no obvious effect on the production of ROS. Treatment with N-acetylcysteine (NAC), a classic ROS scavenger, could suppress ROS production and P38 MAPK activation. These findings suggested that KL could alleviate PQ-caused ALI via inhibiting ROS/P38 MAPK signaling-regulated inflammatory responses and mitochondria-dependent apoptosis.

Ghrelin ameliorates A549 cell apoptosis caused by paraquat via p38-MAPK regulated mitochondrial apoptotic pathway

Paraquat has relatively strong detrimental effects on humans and animals and can cause acute lung injury with high mortality. Ghrelin is a brain-gut peptide which plays important roles in regulating various physiological processes. This study investigated whether ghrelin could inhibit paraquat-induced lung injuries and attempted to elucidate the possible molecular mechanisms. A549 cells were preincubated with different concentrations of ghrelin and then treated with 200 μM of PQ for 24 h. Then cell survival, apoptosis, cellular oxidative stress and lipid peroxidation of A549 cells were detected after different treatments. Subsequently, we analyzed the mitochondrial membrane potential (ΔΨm) and measured caspase-3 activation in A549 cells. In addition, we investigated the activation of the MAPKs pathway and the function of p38-MAPK within mitochondrial apoptosis. Our study indicated that ghrelin administration improved cell viability and reduced apoptosis of PQ-treated A549 cells dose-dependently. Ghrelin treatment reduced the elevation of ROS and MDA, while improved GSH content in A549 cells after paraquat exposure. Moreover, we found that ghrelin dose-dependently increased ΔΨm and decreased caspase-3 activity. The phosphorylated p38 MAPK and JNK levels elevated following PQ exposure, while the phosphorylation of p38 MAPK decreased following ghrelin pretreatment. p38 MAPK siRNA or SB203580 pretreatment ameliorated PQ-caused cell injury and apoptosis related signals, however, the intracellular ROS production was not affected. N-Acetylcysteine (NAC), a classic antioxidant pretreatment decreased the phosphorylated p38 MAPK level and intracellular ROS production, alleviated cell injury, and inhibited apoptosis. The results showed that p38-MAPK pathway plays an important role in PQ-caused alveolar epithelial cell insult, and ghrelin might attenuate PQ-induced cell injury by inhibiting ROS-induced p38-MAPK modulated mitochondrial apoptotic pathway.

Retrospective study of clinical features and prognosis of edaravone in the treatment of paraquat poisoning

To observe whether edaravone can protect organs and inhibit pulmonary fibrosis in patients with paraquat poisoning and to provide a method for clinical intervention for paraquat poisoning.Forty-four cases of paraquat poisoning were collected from March 2011 to December 2017 in our hospital. Eighteen cases from March 2011 to November 2013 did not receive edaravone treatment and were considered the control group, and 26 cases from January 2014 to December 2017 were treated with edaravone and were considered the observation group. Injuries to the central nervous system, heart, liver, kidney, and digestive system were evaluated on at 24 hours, 3 days, and 7 days after hospitalization. The expression of serum inflammatory factors (interleukin [IL]-6, IL-10, tumor necrosis factor-α [TNF-α]) and oxidative stress correlation (superoxide dismutase [SOD] and malondialdehyde [MDA]) were assayed at 24 hours, 3 days, and 7 days after being hospitalized. After 7, 14, and 30 days, the changes in pathological lung characteristics in the 2 groups were assessed, and survival rates were calculated.Edaravone significantly increased the serum levels of SOD and obviously markedly reduce the serum levels of IL-6, IL-10, TNF-α, and MDA in patients poisoned with paraquat (P < .05). Edaravone significantly protected the liver (P = .021), cardiovascular (P = .031), and renal (P = .028) organs of patients from paraquat poisoning-induced injury after 7 days but had no significant protection or improvement on respiratory and digestive tract damage. Edaravone delayed the occurrence of pulmonary fibrosis and increase the survival time of patients at 7 and 14 days (P < .05). However, the 1-month follow-up found that edaravone did not reduce pulmonary fibrosis (77.8% vs 73.1%, P = .615) and did not increase the survival rate of the patients (61.1% vs 65.3%, P = .853).Edaravone is beneficial for protecting the kidneys and liver from paraquat poisoning through reducing oxidative stress and inhibiting inflammatory response. It can also inhibit the pulmonary fibrosis process and prolong the survival time of the patients. However, no significant improvements were seen in the probability of pulmonary fibrosis and the survival rate.

Inhibition of mesenchymal stromal cells' chemotactic effect to ameliorate paraquat-induced pulmonary fibrosis

BACKGROUND

Paraquat (PQ) poisoning is one of the leading causes of suicide attempts in China signature by acute onset of respiratory distress with massive matrix production resulting in progressive pulmonary fibrosis. There is no specific antidote and mortality remains high without effective treatment available. The cellular mechanisms underlying PQ-induced pulmonary fibrosis remain largely unknown.

OBJECTIVES

To determine the origin of mesenchymal stem cells (MSCs) migrated to the lung after PQ exposure and their roles in PQ-induced pulmonary fibrosis, to further explore the possible mechanisms involved in these processes, and to help finding novel therapies.

METHODS

We used a combination of lineage tracking techniques to investigate the contributions of several cells of MSCs, marked by Nestin or CXCL12, and traced their co-expression of α-smooth muscle actin (α-SMA), a marker for fibrosis, or their co-location with matrix production, marked by collagen-1 production (Col1-GFP) following PQ exposure. Then, we used a CXCL12flox/flox; Prx1-Cre mice and a pharmacologic agent AMD3100 to selectively deplete chemotactic mechanism of the MSCs, and tested pro-fibrotic pathways, fibrotic processes and survival of mice after PQ exposure.

RESULTS

Our results showed that after paraquat exposure, the residential Nestin + MSCs were quickly expanded and contributed to extracellular matrix production. Moreover, when we used a CXCL12flox/flox; Prx1-Cre mice to selectively deplete chemotactic mechanism of the MSC, we found that PQ exposure in these mice failed to activate pro-fibrotic pathways including TGF-β, Wnt and EGFR signaling. Furthermore, when the chemotactic effect of MSCs via CXCL12 was blocked by a pharmacologic agent, AMD3100, it alleviated the development of the fibrotic process and improved survival rate in mice exposed to PQ.

CONCLUSION

Collectively, our data suggest paraquat intoxication rapidly activated Nestin + MSCs and that blocking chemotactic effects of MSCs by perivascular CXCL12 inhibition may effectively protect pulmonary injury following paraquat exposure. Our results revealed a novel mechanism for post-PQ lung injury and indicated a novel therapeutic option to attenuate fibrosis induced by paraquat.

Apigenin reverses lung injury and immunotoxicity in paraquat-treated mice

Paraquat (PQ) induces acute lung injury (ALI) and immunotoxicity. Apigenin exerts anti-oxidant and anti-inflammatory properties. The purpose of this study was to investigate the possible protective effects of apigenin on PQ-induced ALI and immunotoxicity in mice. Female C57BL/6 mice received a single injection of PQ (50 mg/kg). Apigenin was given for 7 consecutive days starting 5 days before PQ exposure. The toxicity markers were evaluated in terms of weight loss, lung histopathology, oxidative stress, inflammation, and T cell functions after PQ exposure. Poisoned mice exhibited severe lung tissue lesions, inflammatory cell infiltration and the release of pro-inflammatory cytokines IL-6 and TNF-α. PQ administration increased the lung wet/dry ratios and lipid peroxidation by the increase of MDA levels and decreased anti-oxidase activity including SOD, GSH-PX, and CAT. While such effect on lung was reversed by apigenin. Importantly, PQ-induced immunotoxicity was also observed in a decrease of spleen weight, inhibition of T cell proliferation and T-cell secreting IL-2 from splenocytes. Further mechanism analysis found that PQ administration could decrease total splenocytes, CD4⁺ and CD8⁺ T cells, SOD, GSH-PX, and CAT activity, and increased the levels of MDA and the concentrations of pro-inflammatory cytokines IL-6 and TNF-α compared to control mice. However, apigenin treatment reversed PQ-induced immunotoxicity. In summary, all results suggest that apigenin has beneficial effects on PQ-induced ALI and immunotoxicity possibly, and it could be related, at least in part, to its ability in modulating inflammation and oxidative stress, although in-depth studies might be needed to fully understand the mechanism of action.

A review of current studies on cellular and molecular mechanisms underlying pulmonary fibrosis induced by chemicals

Several studies showed that the inflammatory and fibrotic responses induced by polyhexamethylene guanidine phosphate (PHMG-p) were similar to those observed for idiopathic pulmonary fibrosis in South Korea in 2011. "Omic" technologies can be used to understand the mechanisms underlying chemical-induced diseases. Studies to determine the toxicity of chemicals may facilitate understanding of the mechanisms underlying the development of pulmonary fibrosis at a molecular level; thus, such studies may provide information about the toxic characteristics of various substances. In this review, we have outlined the cellular and molecular mechanisms underlying idiopathic pulmonary fibrosis and described pulmonary fibrosis induced by various chemicals, including bleomycin, paraquat, and PHMG-p, based on the results of studies performed to date.

β-Nitrostyrene derivatives attenuate LPS-mediated acute lung injury via the inhibition of neutrophil-platelet interactions and NET release

Acute lung injury (ALI) and the acute respiratory distress syndrome (ARDS) are high-mortality and life-threatening diseases that are associated with neutrophil activation and accumulation within lung tissue. Emerging evidence indicates that neutrophil-platelet aggregates (NPAs) at sites of injury increase acute inflammation and contribute to the development of ALI. Although numerous studies have increased our understanding of the pathophysiology of ALI, there is still a lack of innovative and useful treatments that reduce mortality, emphasizing that there is an urgent need for novel treatment strategies. In this study, a new series of small compounds of β-nitrostyrene derivatives (BNSDs) were synthesized, and their anti-inflammatory bioactivities on neutrophils and platelets were evaluated. The new small compound C7 modulates neutrophil function by inhibiting superoxide generation and elastase release. Compound C7 elicits protective effects on LPS-induced paw edema and acute lung injury via the inhibition of neutrophil accumulation, proinflammatory mediator release, platelet aggregation, myeloperoxidase activity, and neutrophil extracellular trap (NET) release. NET formation was identified as the bridge for the critical interactions between neutrophils and platelets by confocal microscopy and flow cytometry. This research provides new insights for elucidating the complicated regulation of neutrophils and platelets in ALI and sheds further light on future drug development strategies for ALI/ARDS and acute inflammatory diseases.

Hypoxia-inducible factor-1α regulates epithelial-to-mesenchymal transition in paraquat-induced pulmonary fibrosis by activating lysyl oxidase

Pulmonary fibrosis (PF) is one of the most prevalent causes of death following paraquat (PQ) poisoning. As demonstrated in previous studies by the present authors, epithelial-to-mesenchymal transition (EMT) is associated with PQ-induced PF. In addition, hypoxia-inducible factor-1α (HIF-1α) and lysyl oxidase (LOX) promote EMT following PQ poisoning. However, the association between HIF-1α- and LOX-mediated regulation of EMT remains unclear. The present study investigated the association between HIF-1α and LOX with regard to PQ-induced EMT. A549 and RLE-6TN cells were treated with PQ, and HIF-1α and LOX expression was silenced with short interfering RNAs. Changes in the expression of HIF-1α, LOX, β-catenin and EMT-related makers were detected using real-time quantitative polymerase chain reaction, immunofluorescence, and western blotting. HIF-1α and LOX were associated with PQ-induced EMT, and their expression levels were significantly increased (P<0.05). LOX expression was significantly decreased following PQ poisoning when HIF-1α expression was inhibited (P<0.05). However, the level of HIF-1α did not change significantly when LOX was silenced. The expression level of β-catenin and the degree of EMT were significantly decreased following HIF-1α and LOX silencing in both cell lines (P<0.05). The association between HIF-1α and LOX in regulating EMT during PQ-induced PF may be unidirectional. HIF-1α may regulate PQ-induced EMT through the LOX/β-catenin pathway.

Prognostic comparison of goal-oriented hemoperfusion and routine hemoperfusion combined with continuous venovenous hemofiltration for paraquat poisoning

Objective

To investigate the impact of goal-oriented hemoperfusion (HP) with monitoring of the paraquat concentration on the prognosis of patients with acute paraquat poisoning.

Methods

This prospective observational study involved patients with acute paraquat poisoning admitted from March 2012 to September 2015. The patients received either goal-oriented or routine HP. All other treatments were the same between the two groups. The primary endpoint was 28-day mortality after poisoning. The secondary endpoints were the incidence of organ dysfunction within 7 days and 7-day mortality.

Results

Eighty-four patients were enrolled (49 in the control group and 35 in the goal-oriented group). The two groups were similar in terms of clinical characteristics. There was no significant difference in the incidence of organ dysfunction between the two groups within 1 week of admission. Mortality on day 7 was significantly lower in the goal-oriented than control group, but there was no difference on day 28. However, 28-day mortality was significantly lower in the goal-oriented group among patients with an oral dose of ≤50 ml.

Conclusions

HP with monitoring of the urine paraquat concentration as goal-oriented therapy can reduce the early mortality of paraquat poisoning.

Tissue metabolic changes for effects of pirfenidone in rats of acute paraquat poisoning by GC-MS

We developed a metabolomic method to evaluate the effect of pirfenidone on rats with acute paraquat (PQ) poisoning, through the analysis of various tissues (lung, liver, kidney, and heart), by gas chromatography–mass spectrometry (GC-MS). Thirty-eight rats were randomly divided into a control group, an acute PQ (20 mg kg−1) poisoning group, a pirfenidone (20 mg kg−1) treatment group, and a pirfenidone (40 mg kg−1) treatment group. Partial least squares-discriminate analysis (PLS-DA) revealed metabolic alterations in rat tissue samples from the two pirfenidone treatment groups after acute PQ poisoning. The PLS-DA 3D score chart showed that the rats in the acute PQ poisoning group were clearly distinguished from the rats in the control group. Also, the two pirfenidone treatment groups were distinguished from the acute PQ poisoning group and control group. Additionally, the pirfenidone (40 mg kg−1) treatment group was separated farther than the pirfenidone (20 mg kg−1) treatment group from the acute PQ poisoning group. Evaluation of the pathological changes in the rat tissues revealed that treatment with pirfenidone appeared to decrease pulmonary fibrosis in the acute PQ poisoning rats. The results indicate that pirfenidone induced beneficial metabolic alterations in the tissues of rats with acute PQ poisoning. Rats with acute PQ poisoning exhibited a certain reduction in biochemical indicators after treatment with pirfenidone, indicating that pirfenidone could protect liver and kidney function. Accordingly, the developed metabolomic approach proved to be useful to elucidate the effect of pirfenidone in rats of acute PQ poisoning.

Hypokalemia is a biochemical signal of poor prognosis for acute paraquat poisoning within 4 hours

Anecdotal reports have suggested that hypokalemia is an independent predictor of mortality in patients with acute paraquat poisoning. However, the clinical significance of hypokalemia has not been systematically investigated in the early stage of paraquat poisoning. This study aimed to evaluate whether initial hypokalemia is a good predictor of mortality in patients with acute paraquat poisoning within 4 h. We retrospectively analyzed patients who were admitted to the emergency department after paraquat poisoning between September 2012 and January 2015. Demographic, clinical, and laboratory data were recorded, and the prognostic significance of hypokalemia was analyzed. A total of 120 patients were included. The 60-day mortality was 71.7 %. Serum potassium concentrations were significantly lower in non-survivors (3.1 ± 0.5 mmol/L) than in survivors (3.8 ± 0.3 mmol/L, P < 0.001). Independent predictors of death were amount of paraquat ingested (hazard ratio 1.005; 95 % confidence interval 1.002-1.007), serum potassium (0.498, 0.277-0.897), bicarbonate (0.934, 0.876-0.995), and white blood cell count (1.032, 1.001-1.065). For receiver operating characteristic curve analysis, serum potassium had an area under the curve of 0.852 (95 % confidence interval 0.784-0.920, P < 0.001), and the best cutoff value was 3.5 mmol/L (sensitivity, 88.2 %; specificity, 75.6 % in predicting survivors). Kaplan-Meier analysis showed that decreased serum potassium concentrations were associated with an increase in 60-day mortality (P < 0.001). Hypokalemia may be a reliable predictor in evaluating prognosis in paraquat poisoning within 4 h. The mechanism is not clear, and further studies verifying the precise mechanism of hypokalemia are required.

Prognostic value of hematological parameters in patients with paraquat poisoning

Paraquat (PQ) is a non-selective contact herbicide, and acute PQ poisoning has a high mortality. The aim of the present study is to evaluate the prognostic value of hematological parameters in patients with acute PQ poisoning. We retrospectively reviewed the records of patients with acute PQ poisoning from January 2010 to December 2015 at the First Affiliated Hospital, Anhui Medical University (Hefei, China). A total of 202 patients were included in the study, and the 30-day mortality was 51.98%. Leukocyte, neutrophil counts and neutrophil-lymphocyte ratio (NLR) were significantly higher in non-survivors than in survivors. In the receiver operating characteristic (ROC) curve analysis, the NLR had an area of 0.916(95%CI, 0.877–0.954) and the optimal cut-off value was 10.57 (sensitivity, 86.70%; specificity, 83.51%; Youden’s index, 0.702). The leukocyte counts had an area of 0.849(95%CI, 0.796–0.902) and the optimal cut-off value was 13.15 × 10³/mm³ (sensitivity, 77.10%; specificity, 83.50%; Youden’s index, 0.606). The neutrophil counts had an area of 0.878(95%CI, 0.830–0.925) and the optimal cut-off value was 10.10 × 10³/mm³ (sensitivity, 83.80%; specificity, 79.38%; Youden’s index, 0.632). NLR, leukocyte and neutrophil counts are associated with the 30-day mortality, which may be useful and simple parameters in predicting the prognosis of PQ poisoning.

Acute paraquat exposure determines dose-dependent oxidative injury of multiple organs and metabolic dysfunction in rats: impact on exercise tolerance

This study investigated the pathological morphofunctional adaptations related to the imbalance of exercise tolerance triggered by paraquat (PQ) exposure in rats. The rats were randomized into four groups with eight animals each: (a) SAL (control): 0.5 ml of 0.9% NaCl solution; (b) PQ10: PQ 10 mg/kg; (c) PQ20: PQ 20 mg/kg; and (d) PQ30: PQ 30 mg/kg. Each group received a single injection of PQ. After 72 hours, the animals were subjected to an incremental aerobic running test until fatigue in order to determine exercise tolerance, blood glucose and lactate levels. After the next 24 h, lung, liver and skeletal muscle were collected for biometric, biochemical and morphological analyses. The animals exposed to PQ exhibited a significant anticipation of anaerobic metabolism during the incremental aerobic running test, a reduction in exercise tolerance and blood glucose levels as well as increased blood lactate levels during exercise compared to control animals. PQ exposure increased serum transaminase levels and reduced the glycogen contents in liver tissue and skeletal muscles. In the lung, the liver and the skeletal muscle, PQ exposure also increased the contents of malondialdehyde, protein carbonyl, 8-hydroxy-2'-deoxyguanosine, superoxide dismutase and catalase, as well as a structural remodelling compared to the control group. All these changes were dose-dependent. Reduced exercise tolerance after PQ exposure was potentially influenced by pathological remodelling of multiple organs, in which glycogen depletion in the liver and skeletal muscle and the imbalance of glucose metabolism coexist with the induction of lipid, protein and DNA oxidation, a destructive process not counteracted by the upregulation of endogenous antioxidant enzymes.

Matrine Attenuates COX-2 and ICAM-1 Expressions in Human Lung Epithelial Cells and Prevents Acute Lung Injury in LPS-Induced Mice

Matrine is isolated from Sophora flavescens and shows anti-inflammatory effects in macrophages. Here we evaluated matrine's suppressive effects on cyclooxygenase 2 (COX-2) and intercellular adhesion molecule-1 (ICAM-1) expressions in lipopolysaccharide- (LPS-) stimulated human lung epithelial A549 cells. Additionally, BALB/c mice were given various matrine doses by intraperitoneal injection, and then lung injury was induced via intratracheal instillation of LPS. In LPS-stimulated A549 cells, matrine inhibited the productions of interleukin-8 (IL-8), monocyte chemotactic protein-1, and IL-6 and decreased COX-2 expression. Matrine treatment also decreased ICAM-1 protein expression and suppressed the adhesion of neutrophil-like cells to inflammatory A549 cells. In vitro results demonstrated that matrine significantly inhibited mitogen-activated protein kinase phosphorylation and decreased nuclear transcription factor kappa-B subunit p65 protein translocation into the nucleus. In vivo data indicated that matrine significantly inhibited neutrophil infiltration and suppressed productions of tumor necrosis factor-α and IL-6 in mouse bronchoalveolar lavage fluid and serum. Analysis of lung tissue showed that matrine decreased the gene expression of proinflammatory cytokines, chemokines, COX-2, and ICAM-1. Our findings suggest that matrine improved lung injury in mice and decreased the inflammatory response in human lung epithelial cells.

Paraquat induce pulmonary epithelial-mesenchymal transition through transforming growth factor-β1-dependent mechanism

Pulmonary fibrosis is prevalent in Paraquat (PQ) poisoning. Transforming growth factor β1 (TGF-β1)-induced epithelial-mesenchymal transition (EMT) of Type II alveolar epithelial cells (AT2) contributed to the pulmonary fibrosis in some pulmonary disease. In this study, we investigated whether PQ could induce EMT in AT2 through transforming growth factor β1 (TGF-β1) signal pathway in vitro. Morphological and phenotypic characterizations were evaluated on AT2 cell lines A549 cells in the presence of PQ with or without TGF-β1 inhibitors SB431542 for 5 days. As a result, PQ induced the transition of A549 cells from epithelial morphology to fibroblast-like morphology, associated with the acquisition of migratory properties. Phenotypically, PQ induced-EMT was characterized by loss of epithelial cell markers including E-cadherin and zonula occludens (ZO-1), while up-expressions of mesenchymal cell markers including α-smooth muscle actin (α-SMA) and vimentin, concurrent with increased type I collagen (Col I). SB431542 suppressed PQ-induced EMT via inhibiting expressions of phospho-Smad2 and phospho-Smad3. These findings conclusively demonstrated that the cultured A549 cells underwent EMT in the presence of PQ, and suggested that TGF-β1 played a central role in PQ-induced EMT.

Artificial sweetener neohesperidin dihydrochalcone showed antioxidative, anti-inflammatory and anti-apoptosis effects against paraquat-induced liver injury in mice

The present study evaluated the protective effect of artificial sweetener neohesperidin dihydrochalcone (NHDC) against paraquat (PQ)-induced acute liver injury in mice. A single dose of PQ (75mg/kg body weight, i.p.) induced acute liver toxicity with the evidences of increased liver damage biomarkers, aspartate transaminase (AST) and alanine transaminase (ALT) activities in serum. Consistently, PQ decreased the antioxidant capacity by reducing glutathione peroxidase (GP-X), glutathione-S-transferase (GST) and catalase (CAT) activities, glutathione (GSH) level and total antioxidant capacity (T-AOC), as well as increasing reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) levels. Histopathological examination revealed that PQ induced numerous changes in the liver tissues. Immunochemical staining assay indicated the upregulation of cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) expressions. However, NHDC ameliorates PQ-induced hepatic toxicity in mice by reversing these parameters. Additionally, NHDC significantly inhibited PQ-induced nuclear factor-kappa B (NF-κB) expression and mitochondrial-driven apoptotic signaling. TUNEL assay confirmed that PQ-induced apoptosis was relieved by NHDC. In conclusion, these findings suggested that NHDC showed potent antioxidant, anti-inflammatory and anti-apoptotic effects against PQ-induced acute liver damage.

Fluorofenidone-loaded PLGA microspheres for targeted treatment of paraquat-induced acute lung injury in rats

Lung-targeting fluorofenidone (AKF) loaded PLGA microspheres (AKF-MS) for the treatment of paraquat (PQ)-induced acute lung injury in rats, were constructed by a solvent evaporation method.