Anti-inflammatory effect of Yam Glycoprotein on lipopolysaccharide-induced acute lung injury via the NLRP3 and NF-κB/TLR4 signaling pathway

Metabolomic profile of plasma approach to investigate the mechanism of Poria cocos oligosaccharides attenuated LPS-induced acute lung injury in mice

Poria cocos (Schw.) Wolf (PCW) are the dried sclerotia of Poaceae fungus Poria cocos that contain many biological activity ingredients such as polysaccharides and triterpenoids. The carbohydrates from Poria cocos have been proven to possess anti-inflammatory and antioxidant effects. This study aimed to investigate the impact and mechanism of Poria cocos oligosaccharides (PCO) protecting mice against acute lung injury (ALI). We examined the histopathological analysis of lung injury, inflammatory, and edema levels to evaluate the benefits of PCO during ALI. As a result, PCO improved the lipopolysaccharide (LPS) induced lung injury and decreased the inflammatory cytokines of lung tissue. Simultaneously, PCO alleviated lung edema by regulating the expression of aquaporin5 (AQP5) and epithelial Na+ channel protein (ENaC-α). Additionally, untargeted metabolomics was performed on the plasma of ALI mice via HUPLC-Triple-TOF/MS. The results indicated that linoleic acid, linolenic acid, arachidonic acid, carnosine, glutamic acid, and 1-methylhistamine were the biomarkers in ALI mice. Besides, metabolic pathway analysis suggested PCO affected the histidine and fatty acid metabolism, which were closely associated with inflammation and oxidative reaction of the host. Consequently, the effects of PCO inhibiting inflammation and edema might relate to the reducing pro-inflammatory mediators and the reverse of abnormal metabolic pathways.

Antipyretic and Anti-Inflammatory Effects of Rectal Administration of Reduning Injection in Feverish Rats Induced by Lipopolysaccharide

This study aimed to explore the antipyretic and anti-inflammatory effects of rectal administration of Reduning injection in feverish rats induced by lipopolysaccharide (LPS), and observe the temperature changes and inflammatory indexes. The selected rats were randomly divided into 6 groups, with 10 rats in each group, named as normal empty group, model group, intravenous group (2 mL/kg), low-dose enema group (1 mL/kg), middle-dose enema group (2 mL/kg), and high-dose enema group (4 mL/kg). The hourly temperature variations in rats injected with LPS in the abdomen were recorded. Five hours later, blood samples from the abdominal aorta were collected to monitor immunoglobulin M (IgM), immunoglobulin A (IgA), interleukin (IL)-6, and tumor necrosis factor (TNF)-α. At 5 hours, the fever peak induced by LPS appeared, and obvious antipyretic effects were observed; the effect was optimal in the medium dose enema group at 4 hours (p < 0.05); the IgM value in the enema groups, the intravenous group, and normal empty group was significantly lower than that in the model group; the IgA value in each group was higher than that in the model group, but there was no statistical significance (p > 0.05); values of IL-6 and TNF-α in each group were lower than those in the model group, and the difference was statistically significant except for the high-dose enema group (p > 0.05). Low-dose and medium-dose rectal administration of Reduning injection have inhibitory effects on IL-6, TNF-α, and IgM in feverish rats induced by LPS, but there is no obvious difference compared to intravenous administration and it could achieve an anti-inflammatory effect. There is a possibility of enhancing IgA immunity with rectal administration, but there is no obvious difference compared to intravenous administration, and rectal administration has no significant effect on mucosal immunity.

Cytokine Storm in COVID-19: Insight into Pathological Mechanisms and Therapeutic Benefits of Chinese Herbal Medicines

Cytokine storm (CS) is the main driver of SARS-CoV-2-induced acute respiratory distress syndrome (ARDS) in severe coronavirus disease-19 (COVID-19). The pathological mechanisms of CS are quite complex and involve multiple critical molecular targets that turn self-limited and mild COVID-19 into a severe and life-threatening concern. At present, vaccines are strongly recommended as safe and effective treatments for preventing serious illness or death from COVID-19. However, effective treatment options are still lacking for people who are at the most risk or hospitalized with severe disease. Chinese herbal medicines have been shown to improve the clinical outcomes of mild to severe COVID-19 as an adjunct therapy, particular preventing the development of mild to severe ARDS. This review illustrates in detail the pathogenesis of CS-involved ARDS and its associated key molecular targets, cytokines and signalling pathways. The therapeutic targets were identified particularly in relation to the turning points of the development of COVID-19, from mild symptoms to severe ARDS. Preclinical and clinical studies were reviewed for the effects of Chinese herbal medicines together with conventional therapies in reducing ARDS symptoms and addressing critical therapeutic targets associated with CS. Multiple herbal formulations, herbal extracts and single bioactive phytochemicals with or without conventional therapies demonstrated strong anti-CS effects through multiple mechanisms. However, evidence from larger, well-designed clinical trials is lacking and their detailed mechanisms of action are yet to be well elucidated. More research is warranted to further evaluate the therapeutic value of Chinese herbal medicine for CS in COVID-19-induced ARDS.

Exosomes Derived from hucMSCs Primed with IFN-γ Suppress the NF-κB Signal Pathway in LPS-Induced ALI by Modulating the miR-199b-5p/AFTPH Axis

Exosomes (exos) are primarily responsible for the process of mesenchymal stem cells (MSCs) treatment for acute lung injury (ALI), but the mechanism remains unclear, particularly in altered microenvironment. Therefore, this study aimed to investigate the potential mechanism of exos derived from human umbilical cord mesenchymal stem cells (hucMSCs) primed with interferon-gamma (IFN-γ) on ALI and to propose a promising and cell-free strategy. This study extracted exos from hucMSCs supernatant primed and unprimed with IFN-γ marked with IFN-γ-exos and CON-exos, which were identified and traced. IFN-γ-exos administration to ALI models suppressed the NF-κB signaling pathway compared to CON-exos, which were quantified through western blot and immunohistochemical staining. Reverse transcription-quantitative polymerase chain reaction validated miR-199b-5p expression in the IFN-γ-exos and CON-exos treatment groups. Data analysis, a dual-luciferase reporter assay, and cell transfection were conducted to investigate the target binding between miR-199b-5p and Aftiphilin (AFTPH), with AFTPH expression analyzed via cell immunofluorescence and western blot. Co-immunoprecipitation was conducted for the interaction between AFTPH and NF-κB p65. The result revealed that miR-199b-5p was down-regulated in the IFN-γ-exos treatment group, which had a target binding site with AFTPH, and an interaction with NF-κB p65. Consequently, IFN-γ-exos inhibited the NF-κB signaling pathway in ALI in vitro and in vivo through the miR-199b-5p/AFTPH axis. Our results demonstrated new directions of novel and targeted treatment for ALI.

Global research progress of endothelial cells and ALI/ARDS: a bibliometric analysis

Background

Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are severe respiratory conditions with complex pathogenesis, in which endothelial cells (ECs) play a key role. Despite numerous studies on ALI/ARDS and ECs, a bibliometric analysis focusing on the field is lacking. This study aims to fill this gap by employing bibliometric techniques, offering an overarching perspective on the current research landscape, major contributors, and emerging trends within the field of ALI/ARDS and ECs.

Methods

Leveraging the Web of Science Core Collection (WoSCC) database, we conducted a comprehensive search for literature relevant to ALI/ARDS and ECs. Utilizing Python, VOSviewer, and CiteSpace, we performed a bibliometric analysis on the corpus of publications within this field.

Results

This study analyzed 972 articles from 978 research institutions across 40 countries or regions, with a total of 5,277 authors contributing. These papers have been published in 323 different journals, spanning 62 distinct research areas. The first articles in this field were published in 2011, and there has been a general upward trend in annual publications since. The United States, Germany, and China are the principal contributors, with Joe G. N. Garcia from the University of Arizona identified as the leading authority in this field. American Journal of Physiology-Lung Cellular and Molecular Physiology has the highest publication count, while Frontiers in Immunology has been increasingly focusing on this field in recent years. "Cell Biology" stands as the most prolific research area within the field. Finally, this study identifies endothelial glycocalyx, oxidative stress, pyroptosis, TLRs, NF-κB, and NLRP3 as key terms representing research hotspots and emerging frontiers in this field.

Conclusion

This bibliometric analysis provides a comprehensive overview of the research landscape surrounding ALI/ARDS and ECs. It reveals an increasing academic focus on ALI/ARDS and ECs, particularly in the United States, Germany, and China. Our analysis also identifies several emerging trends and research hotspots, such as endothelial glycocalyx, oxidative stress, and pyroptosis, indicating directions for future research. The findings can guide scholars, clinicians, and policymakers in targeting research gaps and setting priorities to advance the field.

Danshensu methyl ester attenuated LPS-induced acute lung injury by inhibiting TLR4/NF-κB pathway

Acute Lung Injury (ALI) manifests as an acute exacerbation of pulmonary inflammation with high mortality. The potential application of Danshensu methyl ester (DME, synthesized in our lab) in ameliorating ALI has not been elucidated. Our results demonstrated that DME led to a remarkable reduction in lung injury. DME promoted a marked increase in antioxidant enzymes, like superoxide dismutase (SOD), and glutathione (GSH), accompanied by a substantial decrease in reactive oxygen species (ROS), myeloperoxidase (MPO), and malondialdehyde (MDA). Moreover, DME decreased the production of IL-1β, TNF-α and IL-6, in vitro and in vivo. TLR4 and MyD88 expression is reduced in the DME-treated cells or tissues, which further leading to a decrease of p-p65 and p-IκBα. Meanwhile, DME effectively facilitated an elevation in cytoplasmic p65 expression. In summary, DME could ameliorate ALI by its antioxidant functionality and anti-inflammation effects through TLR4/NF-κB, which implied that DME may be a viable medicine for lung injury.

Fortunellin ameliorates LPS-induced acute lung injury, inflammation, and collagen deposition by restraining the TLR4/NF-κB/NLRP3 pathway

OBJECTIVE

Acute lung injury (ALI) is the prevalent respiratory disease of acute inflammation with high morbidity and mortality. Fortunellin has anti-inflammation property, but its role in ALI remains elusive. Thus, this study clarified the function of fortunellin on ALI pathogenesis.

METHODS

The ALI mouse model was established by lipopolysaccharide (LPS) induction, and lung tissue damage was evaluated utilizing hematoxylin-eosin (HE) staining. The edema of lung tissue was measured by the lung wet/dry (W/D) ratio. The lung capillary permeability was reflected by the protein content in bronchoalveolar lavage fluid (BALF). Inflammatory cell infiltration was measured by the evaluation of the content of myeloperoxidase (MPO), neutrophils, and leukocytes in BALF. Cell apoptosis was measured by terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. The secretions of inflammatory cytokines were quantified using enzyme-linked immunosorbent assay (ELISA) assays. Lung tissue collagen deposition was evaluated by Masson staining.

RESULTS

Fortunellin attenuated LPS-induced lung tissue damage and reduced the W/D ratio, the content of MPO in lung tissue, the total protein contents in BALF, and the neutrophils and leukocytes number. Besides, fortunellin alleviated LPS-stimulated lung tissue apoptosis, inflammatory response, and collagen deposition. Furthermore, Fortunellin repressed the activity of the Toll-like receptor 4 (TLR4)/nuclear factor kappa-B (NF-κB)/NLR Family Pyrin Domain Containing 3 (NLRP3) pathway in the LPS-stimulated ALI model and LPS-induced RAW264.7 cells. Moreover, fortunellin attenuated LPS-stimulated tissue injury, apoptosis, inflammation, and collagen deposition of the lung via restraining the TLR4/NF-κB/NLRP3 pathway.

CONCLUSION

Fortunellin attenuated LPS-stimulated ALI through repressing the TLR4/NF-κB/NLRP3 pathway. Fortunellin may be a valuable drug for ALI therapy.

Research progress on the structure, derivatives, pharmacological activity, and drug carrier capacity of Chinese yam polysaccharides: A review

Chinese yam is a traditional Chinese medicine that has a long history of medicinal and edible usage in China and is widely utilised in food, medicine, animal husbandry, and other industries. Chinese yam polysaccharides (CYPs) are among the main active components of Chinese yam. In recent decades, CYPs have received considerable attention because of their remarkable biological activities, such as immunomodulatory, antitumour, hypoglycaemic, hypolipidaemic, antioxidative, anti-inflammatory, and bacteriostatic effects. The structure and chemical alterations of polysaccharides are the main factors affecting their biological activities. CYPs are potential drug carriers owing to their excellent biodegradability and biocompatibility. There is a considerable amount of research on CYPs; however, a systematic summary is lacking. This review summarises the structural characteristics, derivative synthesis, biological activities, and their usage as drug carriers, providing a basis for future research, development, and application of CYPs.

Traditional Chinese Medicine formula Wubi Shanyao Pills protects against reproductive aging by activating SIRT1/3 to reduce apoptosis

ETHNOPHARMACOLOGICAL RELEVANCE

The study of male reproductive aging and its associated concerns holds significant importance within the realm of health issues affecting the elderly population. Wubi Shanyao Pills (WSP), a traditional Chinese patent medicine originating from the Tang Dynasty, has been recognized for its ability to enhance male sexual functions while also tonifying the kidney and spleen. Nevertheless, the precise effects and underlying mechanisms through which WSP ameliorates the decline in reproductive function among aging men remain uncertain.

AIM OF THE STUDY

This study elucidated the distinctive impacts of WSP on ameliorating the decline in reproductive function caused by natural aging, as well as its underlying mechanisms.

MATERIALS AND METHODS

Initially, male mice at the age of 15 months were administered WSP orally at doses of 0.375, 0.75, and 1.50 g/kg per day for a duration of 8 consecutive weeks. The impact of WSP on age-related manifestations in naturally aging mice was assessed based on their behavioral performance. The renal function of the mice was evaluated by measuring serum biochemical indicators, including Creatinine (CR), Uric acid (UA), and Blood urea nitrogen (BUN). Additionally, Superoxide dismutase (SOD) and Malonaldehyde (MDA) levels in renal tissue were determined using applied chemistry methods. Then assessed the levels of Nitric oxide (NO), Total nitric oxide synthase (T-NOS), Guanosine cyclase (GC), and Cyclic guanosine monophosphate (cGMP) in the penile tissue, as well as the expression of Endothelial nitric oxide synthase (eNOS) and Guanylate Cyclase Activator (GUCA) protein, in order to investigate the erectile function of the penis. Additionally, the quality of epididymal sperm was examined using an electron microscope. Furthermore, the serum sex hormone level and related protein expression were determined through the utilization of enzyme-linked immunosorbent assay and immunohistochemistry techniques. Pathological alterations and the ultrastructure of the testis were investigated using hematoxylin-eosin staining and transmission electron microscopy. Subsequently, the apoptosis of spermatogenic cells in the testes was assessed employing TUNEL, immunofluorescence, western blotting, and quantitative real-time polymerase chain reaction.

RESULTS

The administration of WSP has been found to enhance the behavioral performance and sexual behavior in aged mice. It's also could increase in serum levels of CR, UA, and BUN, as well as the elevation of SOD activity in kidney tissue, which subsequently leads to a reduction in MDA levels and an improvement in the structural damage caused by aging in the kidney tissue. Consequently, the renal function is enhanced. Additionally, WSP has been observed to elevate the levels of NO, T-NOS, GC, and cGMP in penile tissue, along with an increase in eNOS and GUCA protein expression, indicating an improvement in penile erectile function. The administration of WSP resulted in a decrease in the occurrence of programmed cell death in testicular germ cells, leading to an enhancement in sperm quality and the overall function of testicular spermatogenesis. This improvement can be attributed to the modulation of hormone levels and the regulation of SIRT1/3, p53, FOXO3, Bax, and Caspase-3 expression.

CONCLUSION

Collectively, our findings indicate that the administration of WSP has the potential to impede the occurrence of programmed cell death in testicular cells by modulating the expression of SIRT1/3 and subsequent genes associated with apoptosis. Consequently, this regulatory mechanism facilitates the proliferation of testicular cells and sustains the spermatogenic function of the testes. Consequently, by modulating the levels of sexual hormones in naturally aging mice, WSP ultimately enhances the quality of sperm and reproductive function. Concurrently, it also ameliorates age-related behavioral changes, renal function, and erectile function.

Purification and characterization of a glycoprotein from Sipunculus nudus and its immune-enhancing activity to RAW 264.7 macrophages

Sipunculus nudus, an edible marine invertebrate, has long been used as traditional Chinese medicine in folk remedies. In order to assess the immunoregulatory activity of glycoproteins in Sipunculus nudus and conduct a structure-activity relationship, a glycoprotein (SGP1) with molecular mass of 9.26 kDa was purified from Sipunculus nudus, and its chemical structure as well as immune-enhancing activity was investigated in this study. Structure analysis revealed that SGP1, a protein-dominate glycoprotein with O-glycosidic bonds, contained 92.8 % protein and 3.1 % saccharide. GC-MS result indicated that the saccharide moieties of SGP1 basically consisted of lyxose (Lyx), xylose (Xyl) as well as glucose (Glu) at a molar proportion of 0.87:4.16:1.36. The fourier transform infrared specoscopy (FT-IR) result proved that SGP1 have a typical characteristic of glycoprotein. Besides, circular dichroism (CD) result showed that SGP1 contained 4.1 % α-helix, 42.5 % β-sheet, 21.4 % β-turn, and 32.0 % random coil, indicating it's mainly a β-sheet glycoprotein. The amino acid sequence of SGP1 shared a similarity to the Myohemerythrin (sp|Q5K473|HEMTM) with protein sequence coverage of 28.3 %. Moreover, the activity evaluation results showed that SGP1 exhibited significant immune-enhancing activity to the RAW 264.7 macrophages by promoting macrophages proliferation, enhancing phagocytic capacity, and simultaneously stimulating the secretions of nitric oxide (NO), interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) via NF-κB pathways. In this study, SGP1 as a novel glycoprotein had an obvious immune-enhancing activity to macrophages, and thus could be applied in the functional foods as a potential immunopotentiator for the hypoimmune population.

Scutellaria baicalensis Pith-decayed Root Inhibits Macrophage-related Inflammation Through the NF-κB/NLRP3 Pathway to Alleviate LPS-induced Acute Lung Injury

Acute lung injury (ALI) is one of the representative "lung heat syndromes" in traditional Chinese medicine (TCM). Scutellaria baicalensis is an herbal medicine used in TCM for treating lung diseases, due to its remarkable anti-inflammatory and antiviral effects. When used in TCM, S. baicalensis root is divided into two categories: S. baicalensis pith-not-decayed root (SN) and S. baicalensis pith-decayed root (SD). Compared to SN, SD has a better effect on lung diseases. We constructed a lipopolysaccharide (LPS)-induced acute lung injury (ALI) mouse model to study the pharmacodynamic mechanism of SD. The ethanolic extract of Scutellaria baicalensis pith-decayed root (EESD) significantly affected LPS-induced ALI by reducing alveolar interstitial thickening, pulmonary edema, and other pathological symptoms, decreasing the infiltration of inflammatory cells, especially macrophages, and inhibiting IL-1β, TNF-α, and IL-6 transcription and translation. Furthermore, in the THP-1 macrophage model induced by LPS, EESD inhibited the expression of phosphorylated nuclear factor inhibitory protein alpha (p-IκBα), phosphorylated nuclear factor-κB P65 (p-p65), cleaved-caspase-1, cleaved-IL-1β protein, and the release of inflammatory factors in the NF-κB/NLRP3 pathway, inhibiting macrophage function. In vivo experiments yielded similar results. Therefore, the present study clarified the potential of EESD in the treatment of ALI and revealed its potential pharmacodynamic mechanism by inhibiting the NF-κB/NLRP3 inflammasome pathway and suppressing the pro-inflammatory phenotype activation of lung tissue macrophages.

The anti-inflammatory activity of GABA-enriched Moringa oleifera leaves produced by fermentation with Lactobacillus plantarum LK-1

Introduction

Gamma-aminobutyric acid (GABA), one of the main active components in Moringa oleifera leaves, can be widely used to treat multiple diseases including inflammation.

Methods

In this study, the anti-inflammatory activity and the underlying anti-inflammatory mechanism of the GABA-enriched Moringa oleifera leaves fermentation broth (MLFB) were investigated on lipopolysaccharide (LPS)-induced RAW 264.7 cells model. The key active components changes like total flavonoids, total polyphenols and organic acid in the fermentation broth after fermentation was also analyzed.

Results

ELISA, RT-qPCR and Western blot results indicated that MLFB could dose-dependently inhibit the secretions and intracellular expression levels of pro-inflammatory cytokines like 1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8) and tumor necrosis factor-α (TNF-α). Furthermore, MLFB also suppressed the expressions of prostaglandin E2 (PGE2) and inducible nitric oxide synthase (iNOS). Moreover, the mRNA expressions of the key molecules like Toll-like receptor 4 (TLR-4) and nuclear factor (NF)-κB in the NF-κB signaling pathway were also restrained by MLFB in a dose-dependent manner. Besides, the key active components analysis result showed that the GABA, total polyphenols, and most organic acids like pyruvic acid, lactic acid as well as acetic acid were increased obviously after fermentation. The total flavonoids content in MLFB was still remained to be 32 mg/L though a downtrend was presented after fermentation.

Discussion

Our results indicated that the MLFB could effectively alleviate LPS-induced inflammatory response by inhibiting the secretions of pro-inflammatory cytokines and its underlying mechanism might be associated with the inhibition of TLR-4/NF-κB inflammatory signaling pathway activation. The anti-inflammatory activity of MLFB might related to the relative high contents of GABA as well as other active constituents such as flavonoids, phenolics and organic acids in MLFB. Our study provides the theoretical basis for applying GABA-enriched Moringa oleifera leaves as a functional food ingredient in the precaution and treatment of chronic inflammatory diseases.

Sipeimine attenuates PM2.5-induced lung toxicity via suppression of NLRP3 inflammasome-mediated pyroptosis through activation of the PI3K/AKT pathway

Exposure to fine particulate matter (PM2.5), an environmental pollutant, significantly contributes to the incidence of and risk of mortality associated with respiratory diseases. Sipeimine (Sip) is a steroidal alkaloid in fritillaries that exerts antioxidative and anti-inflammatory effects. However, protective effect of Sip for lung toxicity and its mechanism to date remains poorly understood. In the present study, we investigated the lung-protective effect of Sip via establishing the lung toxicity model of rats with orotracheal instillation of PM2.5 (7.5 mg/kg) suspension. Sprague-Dawley rats were intraperitoneally administered with Sip (15 mg/kg or 30 mg/kg) or vehicle daily for 3 days before instillation of PM2.5 suspension to establish the model of lung toxicity. The results found that Sip significantly improved pathological damage of lung tissue, mitigated inflammatory response, and inhibited lung tissue pyroptosis. We also found that PM2.5 activated the NLRP3 inflammasome as evidenced by the upregulation levels of NLRP3, cleaved-caspase-1, and ASC proteins. Importantly, PM2.5 could trigger pyroptosis by increased levels of pyroptosis-related proteins, including IL-1β, cleaved IL-1β, and GSDMD-N, membrane pore formation, and mitochondrial swelling. As expected, all these deleterious alterations were reversed by Sip pretreatment. These effects of Sip were blocked by the NLRP3 activator nigericin. Moreover, network pharmacology analysis showed that Sip may function via the PI3K/AKT signaling pathway and animal experiment validate the results, which revealed that Sip inhibited NLRP3 inflammasome-mediated pyroptosis by suppressing the phosphorylation of PI3K and AKT. Our findings demonstrated that Sip inhibited NLRP3-mediated cell pyroptosis through activation of the PI3K/AKT pathway in PM2.5-induced lung toxicity, which has a promising application value and development prospect against lung injury in the future.

USP9X promotes lipopolysaccharide-stimulated acute lung injury by deubiquitination of NLRP3

Alveolar epithelial cells (AECs) function as a vital defense barrier avoiding the invasion of exogenous agents and preserving the functional and structural integrity of lung tissues, while damage/breakdown of this airway epithelial barrier is frequently associated with the pathogenesis of acute lung injury (ALI). NOD-like receptor family, pyrindomain-containing 3 (NLRP3) inflammasome activation-associated pyroptosis is involved in the development of ALI. Yet, how the activity of NLRP3 inflammasome is regulated in the context of ALI remains unknown. Herein we hypothesized that USP9X, an important deubiquitinase, participates in modulating the activation of NLRP3 inflammasome, thereby affecting the phenotypes in a lipopolysaccharide (LPS)-stimulated AEC model. Human pulmonary AECs were subjected to LPS/adenosine triphosphate (ATP) treatment to induce NLRP3 inflammasome activation and cell pyroptosis. Knockdown and overexpression of USP9X were applied to validate the function of USP9X. Inhibitors of proteinase and protein synthesis, as well as approach of co-immunoprecipitation coupled with Western blot, were utilized to explore the molecular mechanism. LPS/ATP challenge resulted in pronouncedly increased pyroptosis of AECs, activation of NLRP3 inflammasome and release of interleukin (IL)-1β and IL-18 cytokines, while downregulation of USP9X could reverse these alterations. USP9X was found to have marked impact on NLRP3 protein instead of mRNA level. Furthermore, increased ubiquitination of NLRP3 was observed upon downregulating USP9X. Additionally, the inhibitory effect of USP9X downregulation was reversed by NLRP3 overexpression, while the promoting impact of USP9X overexpression was dampened by NLRP3 inhibitor in terms of cell pyroptosis and cytokine secretion. USP9X modulated the activity of NLRP3 inflammasome and pyroptosis of AECs via its deubiquitination function.

Combination of Houttuynia cordata polysaccharide and Lactiplantibacillus plantarum P101 alleviates acute liver injury by regulating gut microbiota in mice

BACKGROUND

Polysaccharides and probiotics can play an outstanding role in the treatment of liver disease by regulating gut microbiota. Recently, the combined therapeutic effect of probiotics and polysaccharides has attracted the attention of researchers. Houttuynia cordata polysaccharide (HCP) combined with Lactiplantibacillus plantarum P101 was used to prevent carbon tetrachloride (CCl₄ )-induced acute liver injury (ALI) in mice, and its effect on gut microbiota regulation was explored.

RESULTS

Results showed that, in mice, HCP combined with L. plantarum P101 significantly alleviated oxidative stress and inflammatory injury in the liver by activating Nrf2 signals and inhibiting NF-κB signals. The analysis of gut microbiota revealed that the combination of HCP and L. plantarum P101 increased the abundance of beneficial bacteria such as Alloprevotella, Roseburia, and Akkermansia, but reduced that of the pro-inflammatory bacteria Alistipes, Enterorhabdus, Anaerotruncus, and Escherichia-Shigella. Correlation analysis also indicated that the expression of Nrf2 and TLR4/NF-κB was connected to the changes in gut microbiota composition. Houttuynia cordata polysaccharide combined with L. plantarum P101 can regulate the gut microbiota and then mediate the gut-liver axis to activate the antioxidant pathway and inhibit inflammatory responses, thereby alleviating CCl₄ -induced ALI.

CONCLUSION

Our study provided a new perspective on the use of polysaccharides combined with probiotics in the treatment of liver disease. © 2022 Society of Chemical Industry.

Aspirin eugenol ester alleviates lipopolysaccharide-induced acute lung injury in rats while stabilizing serum metabolites levels

Aspirin eugenol ester (AEE) was a novel drug compound with aspirin and eugenol esterified. AEE had various pharmacological activities, such as anti-inflammatory, antipyretic, analgesic, anti-oxidative stress and so on. In this study, it was aimed to investigate the effect of AEE on the acute lung injury (ALI) induced by lipopolysaccharide (LPS) in rats. In vitro experiments evaluated the protective effect of AEE on the LPS-induced A549 cells. The tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) were measured in the cell supernatant. The Wistar rats were randomly divided into five groups (n = 8): control group, model group (LPS group), LPS + AEE group (AEE, 54 mg·kg-1), LPS + AEE group (AEE, 108 mg·kg-1), LPS + AEE group (AEE, 216 mg·kg-1). The lung wet-to-dry weight (W/D) ratio and immune organ index were calculated. WBCs were counted in bronchoalveolar lavage fluid (BALF) and total protein concentration was measured. Hematoxylin-Eosin (HE) staining of lung tissue was performed. Glutathione (GSH), glutathione peroxidase (GPx), catalase (CAT), antioxidant superoxide dismutase (SOD), total antioxidant capacity (T-AOC), lactate dehydrogenase (LDH), C-reactive protein (CRP), myeloperoxidase (MPO), malondialdehyde (MDA), macrophage mobility inhibitory factor (MIF), TNF-α, IL-6, and IL-1β activity were measured. The metabolomic analysis of rat serum was performed by UPLC-QTOF-MS/MS. From the results, compared with LPS group, AEE improved histopathological changes, reduced MDA, CRP, MPO, MDA, and MIF production, decreased WBC count and total protein content in BALF, pro-inflammatory cytokine levels, immune organ index and lung wet-dry weight (W/D), increased antioxidant enzyme activity, in a dose-dependent manner. The results of serum metabolomic analysis showed that the LPS-induced ALI caused metabolic disorders and oxidative stress in rats, while AEE could ameliorate it to some extent. Therefore, AEE could alleviate LPS-induced ALI in rats by regulating abnormal inflammatory responses, slowing down oxidative stress, and modulating energy metabolism.

Carvedilol alleviates lipopolysaccharide (LPS)-induced acute lung injury by inhibiting Ras homolog family member A (RhoA)/ROCK activities

Carvedilol possess multiple functions such as antioxidation and neuroprotection RhoA/ROCK is reported to participate in acute lung injury (ALI). The aim of the present study was to explore the role of carvedilol in LPS-induced ALI. BEAS2B cells were subjected to LPS for the construction of in vitro ALI model. After that, the protective effects of carvedilol were evaluated by Cell Counting Kit-8 (CCK-8). The activities of RhoA/ROCK were then measured to confirm its association with carvedilol by quantitative reverse transcription PCR (RT-qPCR) and Western blot. Then, the cell viability, inflammatory responses, oxidative stress and apoptosis were detected by CCK-8, enzyme linked immunosorbent assay (ELISA), oxidative stress detection kits, and TdT-mediated dUTP Nick-End Labeling (TUNEL) respectively. Inflammation- and apoptosis-related markers were also measured by Western blot. The cell viability reduced by LPS in BEAS2B cells was elevated by carvedilol. Moreover, RhoA/ROCK were found to be suppressed by carvedilol administration. The cell viability, inflammation, oxidative stress and apoptosis of LPS-induced BEAS2B cells were aggravated upon RhoA was overexpressed. Collectively, carvedilol exerts a protective effect against LPS-induced injury that could be ascribed to its anti-inflammatory and antioxidative character through modulating the RhoA/ROCK activities.

Astaxanthin ameliorates lipopolysaccharide-induced acute lung injury via inhibition of inflammatory reactions and modulation of the SOCS3/JAK2/STAT3 signaling pathways in mice

The results showed that astaxanthin had a protective effect on LPS-induced acute lung injury in mice, and its protective mechanism was through activating the SOCS3/JAK2/STAT3 signaling pathway.

Antipharyngitis Effects of Syringa oblata L. Ethanolic Extract in Acute Pharyngitis Rat Model and Anti-Inflammatory Effect of Ir-Idoids in LPS-Induced RAW 264.7 Cells

Acute pharyngitis is an inflammation of the pharyngeal mucous membrane and submucous lymphoid tissues. Unsatisfactory treatment and repeated occurrences might cause chronic pharyngitis and other complications. Syringa oblata L. (S. oblata) is a traditional Chinese medicine that exhibited a significant therapeutic effect on various inflammatory diseases. Its commercial drug Yan Li Xiao (YLX) capsule is used as a cure for the treatment of inflammatory diseases, such as bacillary dysentery, tonsillitis, bronchitis, and acute gastroenteritis. However, studies about S. oblata relieving acute pharyngitis are rare. In this study, high-performance liquid chromatography (HPLC) was used to analyze the chemical profile of S. oblata, and the bioactive phytoconstituents were isolated and identified by nuclear magnetic resonance (NMR) and mass spectrometry. An ammonia-induced acute pharyngitis rat model was established to estimate the protective effect of S. oblata in vivo for the first time. The severity of pharyngitis was observed by appearance index and HE staining. The cytokines expression was performed by ELISA. Crucial proteins expression associated with TLR4/NF-κB/MAPK and NLRP3 inflammasome signaling pathways were analyzed by western blotting and immunohistochemistry. Furthermore, the anti-inflammatory effect of isolated compounds was evaluated by suppressing lipopolysaccharide- (LPS-) induced NO generation and regulating the cytokines levels in RAW 264.7 cells. The results showed that S. oblata exhibited a protective effect in the ammonia-induced acute pharyngitis rat model, and the compounds exert potential anti-inflammatory properties against LPS-activated RAW 254.7 cells.

Identification of key immune genes for sepsis-induced ARDS based on bioinformatics analysis

Regarding the extremely high mortality caused by sepsis-induced acute respiratory distress syndrome (ARDS), it is urgent to develop new biomarkers of sepsis-induced ARDS for treatment. Here, 532 differential expression genes (DEGs) related to sepsis and 433 DEGs related to sepsis-induced ARDS were screened in the GSE32707 dataset. Compared with sepsis samples, sepsis ARDS samples showed a higher infiltration of activated memory CD4 T cells and naive B cells, but a relatively lower infiltration of CD8 T cells. The pink and green modules which are significantly associated with sepsis-induced ARDS were then screened through co-expression network analysis. Differentially up-regulated GYPE and aberrantly down-regulated HSPB1, were subsequently found in the pink module of ARDS. CD81 and RPL22, two differentially low-expressed genes peculiar to ARDS, were identified in the green module. The function of CD81 was verified at the cellular level, and it was found that the up-regulation of CD81 in A549 could alleviate the LPS-induced injury of A549 cells. More importantly, the overexpressed CD81 can also increase the content of CD4⁺ CD25⁺ Foxp3⁺ Treg in Jurkat cells, and after the co-culture of overexpressed CD81 Jurkat cells with LPS treatment A549 cells, the LPS-induced lung epithelial cell damage can be improved. Overall, four new plasma biomarker candidates were found in sepsis-induced ARDS, and we verified that CD81 may play critical roles in the biological and immunological processes of sepsis-induced ARDS.

miR-122-5p downregulation attenuates lipopolysaccharide-induced acute lung injury by targeting IL1RN

MicroRNAs (miRs) and inflammatory cytokines can induce acute lung injury (ALI), which can develop into acute respiratory distress syndrome in severe cases. Previous research has revealed that miR-122-5p participates in the development of ALI, and that its expression is positively associated with ALI. However, the mechanism by which miR-122-5p contributes to ALI remains to be determined. In the current study, TargetScan and dual luciferase reporter gene assays were used to confirm that IL-1 receptor antagonist (IL1RN) was a target of miR-122-5p. Subsequently, by referring to previous literature, a lipopolysaccharide (LPS)-induced ALI cell model was established. A549 cells were transfected with mimic control or miR-122-5p mimics for 24 h, and 10 µg LPS was used to treat the transfected cells for 12 h. The results revealed that miR-122-5p mimics decreased cell viability and promoted apoptosis. Lactate dehydrogenase (LDH) release assays indicated that miR-122-5p mimics increased LDH release. ELISA demonstrated that miR-122-5p mimics promoted TNF-α, IL-1β and IL-6 expression levels. A549 cells were transfected with inhibitor control, miR-122-5p inhibitor, miR-122-5p inhibitor + control-small interfering (si)RNA or miR-122-5p inhibitor + IL1RN-siRNA for 24 h, after which the cells were treated with 10 µg LPS for 12 h. The results revealed that the effects of the miR-122-5p inhibitor were the opposite of those of the miR-122-5p mimic. All the effects of miR-122-5p inhibitor on LPS-treated A549 cells were significantly reversed by IL1RN-siRNA. Overall, the results highlighted miR-122-5p as a potential novel target for the treatment of ALI.

Chimonanthus nitens Oliv. essential oil mitigates lipopolysaccharide-induced acute lung injury in rats

This study aimed to evaluate the effect of Chimonanthus nitens Oliv. essential oil (named CEO) on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in rats. In the present study, 21 compounds were characterized in CEO by gas chromatography-mass spectrometry analysis. Furthermore, animal data suggested that CEO could protect rats against ALI, as evidence by increasing white blood cell count, reducing immune organ index and improving lung histopathological changes in rats subjected to LPS. Reduction of the levels of IL-1β was also shown during CEO-triggering lung protection in rats. Meanwhile, these protective effects of CEO were accompanied by the attenuation of lipid oxidation, and elevation of antioxidant enzymes, suggesting that enhancement of antioxidant defense was linked to its lung protection. Moreover, a combination with CEO and LPS significantly elevated short-chain fatty acids (SCFAs) compared with LPS alone via increasing propionic, i-butyric, butyric and i-valeric acid on LPS-induced ALI in rats. Therefore, our findings indicated that CEO could alleviate LPS-caused ALI in rats by controlling aberrant inflammation, correcting the redox system, and modulating SCFAs in rats.

Glycoproteins From Rabdosia japonica var. glaucocalyx Regulate Macrophage Polarization and Alleviate Lipopolysaccharide-Induced Acute Lung Injury in Mice via TLR4/NF-κB Pathway

Background and Aims:Rabdosia japonica var. glaucocalyx is a traditional Chinese medicine (TCM) for various inflammatory diseases. This present work aimed to investigate the protective effects of R. japonica var. glaucocalyx glycoproteins on lipopolysaccharide (LPS)-induced acute lung injury (ALI) and the potential mechanism.

Methods: Glycoproteins (XPS) were isolated from R. japonica var. glaucocalyx, and homogeneous glycoprotein (XPS5-1) was purified from XPS. ANA-1 cells were used to observe the effect of glycoproteins on the secretion of inflammatory mediators by enzyme-linked immunosorbent assay (ELISA). Flow cytometry assay, immunofluorescence assay, and Western blot analysis were performed to detect macrophage polarization in vitro. The ALI model was induced by LPS via intratracheal instillation, and XPS (20, 40, and 80 mg/kg) was administered intragastrically 2 h later. The mechanisms of XPS against ALI were investigated by Western blot, ELISA, and immunohistochemistry.

Results:In vitro, XPS and XPS5-1 downregulated LPS-induced proinflammatory mediators production including tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), IL-6, and nitric oxide (NO) and upregulated LPS-induced IL-10 secretion. The LPS-stimulated macrophage polarization was also modulated from M1 to M2. In vivo, XPS maintained pulmonary histology with significantly reducing protein concentration and numbers of mononuclear cells in bronchoalveolar lavage fluid (BALF). The level of IL-10 in BALF was upregulated by XPS treatment. The level of cytokines including TNF-α, IL-1β, and IL-6 was downregulated. XPS also decreased infiltration of macrophages and polymorphonuclear leukocytes (PMNs) in lung. XPS suppressed the expression of key proteins in the TLR4/NF-κB signal pathway.

Conclusion: XPS was demonstrated to be a potential agent for treating ALI. Our findings might provide evidence supporting the traditional application of R. japonica var. glaucocalyx in inflammation-linked diseases.

Sepsis-induced acute lung injury in young rats is relieved by calycosin through inactivating the HMGB1/MyD88/NF-κB pathway and NLRP3 inflammasome

PURPOSE

Sepsis is the primary cause for children's death worldwide. Calycosin (CAL) is an astragalus extract with anti-inflammatory, antioxidant and anti-tumor functions. This study aims to probe the role of CAL in alleviating sepsis-induced acute lung injury (ALI).

PATIENTS AND METHODS

Cecal ligation and puncture (CLP) was carried out in young rats to induce sepsis model, which were then treated with CAL. The histopathological changes of the lung were observed, and the dry/wet (W/D) weight ratio of the lung was calculated to analyze pulmonary edema. Apoptosis was determined by the terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling (TUNEL) assay, and the contents of PaO2, PaCO2 and PaO2/FiO2 in the aortic blood of the rats were monitored by blood-gas analysis. In addition, lipopolysaccharide (LPS) was applied to treat Type II alveolar epithelial cells (AEC-II) to establish an in-vitro sepsis model. Cell viability was detected by the (4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, and apoptosis was examined by flow cytometry. The expression of apoptosis-related proteins Bax, Bcl2 and Caspase3, as well as the HMGB1/MyD88/NF-κB axis and NLRP3 inflammasome were measured by Western Blot. The profiles of inflammatory factors (TNF-α, IL-1β, and MCP-1) and oxidative stress markers (MDA, SOD, and CAT) in rat serum and AEC-II cells were also detected.

RESULTS

CLP induced remarkable lung injury in the young rats. The administration of CAL significantly mitigated pathological injuries of rat lung, reduced lung edema and the apoptosis (labeled by TUNEL). In vitro, CAL treatment improved the damage of LPS-treated AEC-II cells. In addition, CAL dampened inflammation and oxidative stress both in vitro and in vivo, repressed the HMGB1/MyD88/NF-κB pathway and NLRP inflammasome activation induced by CLP or LPS. Interestingly, inhibiting HMGB1 (by ethyl pyruvate, EP) enhanced CAL-mediated protective effects against LPS in AEC-II cells.

CONCLUSION

CAL alleviates sepsis-induced ALI in young rats by inhibiting the HMGB1/MyD88/NF-κB pathway and NLRP3 inflammasome activation.

Ginkgolide B Alleviates Learning and Memory Impairment in Rats With Vascular Dementia by Reducing Neuroinflammation via Regulating NF-κB Pathway

Ginkgobalide B (GB) as the main active ingredient of traditional Chinese medicine Ginkgo biloba extract is reported to reduce neuroinflammation, protect neurons and promote cognitive learning ability. To explore that GB can reduce neuroinflammation through regulating nuclear factor-kappaB (NF-κB) signaling pathway and overcome cognitive dysfunction in rats with vascular dementia (VD), we aim at investigating the potential effect of GB on enhancing cognitive function in rats with VD. It was found that GB improved survival of oxygen-glucose deprivation (OGD) treated SH-SY5Y cells by attenuating inflammatory response via Toll-like Receptor 4 (TLR4)/NF-κB pathway. When rats were treated with bilateral common carotid artery occlusion (BCCAO) for 24 h, saline and GB were administered in Sprague-Dawley (SD) rats via a single intraperitoneal injection for consecutive 14 days. The behavioral changes of VD like rats treated with GB were observed through open field test, Morris water maze (MWM) and Y-maze electric maze. Nissl staining and immunofluorescence were used to observe changes of neurons in the hippocampus of rats. Western blot analysis was performed by detecting NF-κB pathway related inflammatory factors. The results found that GB can significantly improve the learning and memory ability of VD rats by reducing TLR4/NF-κB mediated neuroinflammation. In conclusion, GB seemed to be a potential drug for amelioration of learning and memory impairment in rats with VD.

MiR-494-3p alleviates acute lung injury through regulating NLRP3 activation by targeting CMPK2

Acute lung injury (ALI) is a severe respiratory disorder with a high rate of mortality, and is characterized by excessive cell apoptosis and inflammation. MicroRNAs (miRNAs) play pivotal roles in ALI. This study examined the biological function of miR-494-3p in cell apoptosis and inflammatory response in ALI. For this, mice were injected with lipopolysaccharide (LPS) to generate an in-vivo model of ALI (ALI mice), and WI-38 cells were stimulated with lipopolysaccharide (LPS) to generate an in-vitro model of ALI. We found that miR-494-3p was significantly downregulated in the ALI mice and in the in-vitro model. Overexpression of miR-494-3p inhibited inflammation and cell apoptosis in the LPS-induced WI-38 cells, and improved the symptoms of lung injury in the ALI mice. We then identified cytidine/uridine monophosphate kinase 2 (CMPK2) as a novel target of miR-494-3p in the WI-38 cells. Furthermore, miR-494-3p suppressed cell apoptosis and the inflammatory response in LPS-treated WI-38 cells through targeting CMPK2. The NLRP3 inflammasome is reportedly responsible for the activation of inflammatory processes. In our study, CMPK2 was confirmed to activate the NLRP3 inflammasome in LPS-treated WI-38 cells. In conclusion, miR-494-3p attenuates ALI through inhibiting cell apoptosis and the inflammatory response by targeting CMPK2, which suggests the value of miR-494-3p as a target for the treatment for ALI.

Shenling Baizhu Powder Inhibits RV-SA11-Induced Inflammation and Rotavirus Enteritis via TLR4/MyD88/NF-κB Signaling Pathway

Rotavirus enteritis (RVE) is a common acute intestinal infectious disease caused by rotavirus infection. It is an important cause of death in children younger than 5 years worldwide. Shenling baizhu powder (SBP), a classic traditional Chinese formulation, is one of the most popularly prescribed medicines for digestive diseases. Clinical studies have revealed the protective effects of SBP on RVE. However, the potential mechanism is still unclear. In this study, we aimed to evaluate the anti-rotavirus effect of SBP and its mechanism, focusing on the TLR4/MyD88/NF-κB signaling pathway. Our results demonstrated that, based on the inhibition of the virus-induced cytopathic effect in Caco-2 cells, the concentration for 50% of maximal effect (EC50) and selectivity index (SI) of SBP for RV-SA11 in the serum were 5.911% and 11.63, respectively. A total of 219 active compounds with oral bioavailability ≥30% and drug-likeness ≥ 0.18 were selected from the 10 ingredients present in the formulation of SBP, which acted on 471 potential targets. A total of 226 target genes of RVE were obtained from the GeneCards database. The protein-protein interaction (PPI) network showed that there was a close interaction between 44 common targets of SBP and RVE. The results of Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis showed that SBP acted on RVE through various inflammatory pathways and the intestinal immune network. Subsequently, we investigated the effect of SBP on TLR4/MyD88/NF-κB signaling pathway in vitro. After infection with RV- SA11, the expression of TLR4, MyD88, and NF-κB mRNA and protein increased significantly, which could be abolished by SBP treatment. In addition, the IL-1β, TNF-α, IL-6, and IFN-β levels increased markedly in Caco-2 cells infected with RV-SV11. Treatment with SBP partly reversed the changes of IL-1β, TNF-α, and IL-6, while further increased the level of IFN-β. In conclusion, our study revealed that SBP can significantly inhibit rotavirus replication and proliferation in vitro. The antiviral effect may be related to the regulation of the TLR4/MyD88/NF-κB signaling pathway, followed by the down regulation of inflammatory cytokines and up regulation of IFN-β induced by rotavirus.

Angelica Polysaccharide Ameliorates Sepsis-Induced Acute Lung Injury through Inhibiting NLRP3 and NF-κB Signaling Pathways in Mice

Objective. This study aimed to explore the role of angelica polysaccharide (AP) in sepsis-induced acute lung injury (ALI) and its underlying molecular mechanism. Methods. A sepsis model of cecal ligation and puncture (CLP) in male BALB/C mice was used. Then, 24 h after CLP, histopathological changes in lung tissue, lung wet/dry weight ratio, and inflammatory cell infiltration were analyzed. Next, levels of inflammatory cytokines (tumor necrosis factor-α (TNF-α), interleukin (IL)-1β, IL-6, and IL-18), as well as the activity of myeloperoxidase (MPO), malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione (GSH), were measured to assess the role of AP. The protein expression of NF-κB p65, p-NF-κB p65, IκBα, p-IκBα, nucleotide-binding domain- (NOD-) like receptor protein 3 (NLRP3), ASC, and caspase-1 was detected by western blot. In addition, the expression of p-NF-κB p65 and NLRP3 was detected by immunohistochemistry. Results. AP treatment ameliorated CLP-induced lung injury and lung edema, as well as decreased the number of total cells, neutrophils, and macrophages in bronchoalveolar lavage fluid (BALF). AP reduced the levels of TNF-α, IL-1β, IL-6, and IL-18 in BALF, as well as in serum. Moreover, AP decreased MPO activity and MDA content, whereas increased SOD and GSH levels. AP inhibited the expression of p-NF-κB p65, p-IκBα, NLRP3, ASC, and caspase-1, while promoted IκBα expression. Conclusion. This study demonstrated that AP exhibits protective effects against sepsis-induced ALI by inhibiting NLRP3 and NF-κB signaling pathways in mice.

Inflammatory Caspases Drive Pyroptosis in Acute Lung Injury

Acute lung injury (ALI), a critical respiratory disorder that causes diffuse alveolar injury leads to high mortality rates with no effective treatment. ALI is characterized by varying degrees of ventilation/perfusion mismatch, severe hypoxemia, and poor pulmonary compliance. The diffuse injury to cells is one of most important pathological characteristics of ALI. Pyroptosis is a form of programmed cell death distinguished from apoptosis induced by inflammatory caspases, which can release inflammatory cytokines to clear cells infected by pathogens and promote monocytes to reassemble at the site of injury. And pyroptosis not only promotes inflammation in certain cell types, but also regulates many downstream pathways to perform different functions. There is increasing evidence that pyroptosis and its related inflammatory caspases play an important role in the development of acute lung injury. The main modes of activation of pyroptosis is not consistent among different types of cells in lung tissue. Meanwhile, inhibition of inflammasome, the key to initiating pyroptosis is currently the main way to treat acute lung injury. The review summarizes the relationship among inflammatory caspases, pyroptosis and acute lung injury and provides general directions and strategies to conduct further research.

MiR-122-5p protects against acute lung injury via regulation of DUSP4/ERK signaling in pulmonary microvascular endothelial cells

AIMS

The aim of this study was to explore the role of miR-122-5p in acute lung injury.

MATERIALS AND METHODS

Mice were subjected to intratracheal injection of lipopolysaccharide to establish an acute lung injury model. The mice also received miR-122-5p antagonist and mimic via injection to inhibit or overexpress miR-122-5p in the lung tissue, respectively. In an in vitro experiment, we isolated primary mouse lung microvascular endothelial cells and established a cell injury model via lipopolysaccharide treatment.

KEY FINDINGS

Mice injected with an miR-122-5p antagonist exhibited reduced lung injury, inflammation and oxidative stress, while mice injected with a miR-122-5p mimic exhibited exaggerated lung injury, inflammation and oxidative stress. In an in vitro experiment, we found that the miR-122-5p antagonist suppressed lipopolysaccharide-induced inflammation, apoptosis and oxidative stress. Moreover, miR-122-5p regulated the promoter activity of DUSP4, which negatively regulated ERK1/2 signaling. The use of DUSP4 siRNA counteracted the effects of the miR-122-5p antagonist.

SIGNIFICANCE

Taken together, these results show that miR-122-5p protected against acute lung injury via regulation of DUSP4/ERK signaling in pulmonary microvascular endothelial cells. MiR-122-5p antagonism may be a promising treatment method for acute lung injury.