miR-221-5p-Mediated Downregulation of JNK2 Aggravates Acute Lung Injury

Telocyte-derived exosomes promote angiogenesis and alleviate acute respiratory distress syndrome via JAK/STAT-miR-221-E2F2 axis

Acute respiratory distress syndrome (ARDS) is characterized by severe respiratory failure and significant inflammation, leading to vascular and epithelial cell damage. The absence of effective pharmacologic treatments underscores the need for novel therapeutic approaches. Telocytes (TCs), a newly identified type of interstitial cells, have shown potential in tissue repair and angiogenesis, particularly through the release of exosomal microRNAs (miRNAs). Exosomes were isolated from LPS (lipopolysaccharide)-stimulated TCs and characterized using western blotting and nanoparticle tracking analysis. The role of exosomal miR-221 in angiogenesis was assessed through tube formation, migration, and proliferation assays in mouse vascular endothelial cells (MVECs). The JAK/STAT pathway's involvement in miR-221 regulation was determined using western blotting and qRT-PCR. A dual-luciferase assay confirmed E2F2 as a direct target of miR-221. ARDS mouse model was established via LPS instillation, and the therapeutic effects of TCs-derived exosomes were evaluated by histopathological scoring, cytokine analysis, and endothelial barrier integrity assays. Our findings demonstrated that exosomes from LPS-stimulated TCs significantly promoted angiogenesis, proliferation, and migration in MVECs. These effects were mediated by miR-221, which downregulated E2F2 expression, an important regulator of endothelial cell functions. The JAK/STAT pathway played a crucial role in miR-221 production, with pathway inhibition reducing miR-221 levels and attenuating its pro-angiogenic effects. In vivo, TCs-derived exosomes reduced lung inflammation and tissue damage in ARDS mice, effects that were reversed by miR-221 inhibition. These results suggested that TCs-derived exosomes promoted angiogenesis and alleviated ARDS through the JAK/STAT-miR-221-E2F2 axis.

METTL3-mediated m6A Modification Promotes miR-221-3p Expression to Exacerbate Ischemia/Reperfusion-Induced Acute Lung Injury

Ischemia/reperfusion (I/R)-induced acute lung injury (ALI) represents a prevalent pulmonary pathology. The N6-methyladenosine (m6A) RNA modification is integral in regulating numerous biological processes across various human diseases through the modulation of gene expression. Nevertheless, the precise role and underlying molecular mechanisms of m6A modifications in ALI remain inadequately understood. This study aimed to elucidate the impact of RNA methyltransferase 3 (METTL3)-mediated m6A modification of miR-221-3p on the progression of I/R-induced ALI. Our initial findings demonstrated an upregulation of m6A levels and METTL3 expression in I/R-induced ALI in murine models and hypoxia/reoxygenation (H/R)-induced murine lung epithelial (MLE)-12 cells. Inhibition of METTL3 was observed to reverse H/R-induced apoptotic cell death, oxidative stress, and inflammatory cytokine secretion. Furthermore, METTL3 was found to enhance the expression of miR-221-3p in an m6A-dependent manner, thereby contributing to ALI pathogenesis. In addition, miR-221-3p was shown to negatively regulate PTEN expression, while METTL3 facilitated phosphorylated AKT expression via the miR-221-3p/PTEN axis. Functional experiments further revealed that the downregulation of PTEN negated the inhibitory effects of METTL3 knockdown in H/R-treated MLE-12 cells. In conclusion, our study demonstrates that the METTL3-mediated m6A modification of miR-221-3p exacerbates ALI through modulation of the PTEN/AKT pathway. Therapeutic strategies aimed at targeting the METTL3/m6A/miR-221-3p/PTEN/AKT axis may offer a promising approach to mitigate I/R-induced ALI.

Protective role of triiodothyronine in sepsis‑induced cardiomyopathy through phospholamban downregulation

Sepsis is often a cause of mortality in patients admitted to the intensive care unit. Notably, the heart is the organ most susceptible to the impact of sepsis and this condition is referred to as sepsis‑induced cardiomyopathy (SIC). Low triiodothyronine (T3) syndrome frequently occurs in patients with sepsis, and the heart is one of the most important target organs for the action of T3. Phospholamban (PLN) is a key protein associated with Ca2+‑pump‑mediated cardiac diastolic function in the myocardium of mice with SIC, and PLN is negatively regulated by T3. The present study aimed to explore whether T3 can protect cardiac function during sepsis and to investigate the specific molecular mechanism underlying the regulation of PLN by T3. C57BL/6J mice and H9C2 cells were used to establish in vivo and in vitro models, respectively. Myocardial damage was detected via pathological tissue sections, a Cell Counting Kit-8 assay, an apoptosis assay and crystal violet staining. Intracellular calcium levels and reactive oxygen species were detected by Fluo‑4AM and DHE fluorescence. The protein and mRNA expression levels of JNK and c‑Jun were measured by western blotting and reverse transcription‑quantitative PCR to investigate the molecular mechanisms involved. Subsequently, 100 clinical patients were recruited to verify the clinical application value of PLN in SIC. The results revealed a significant negative correlation between PLN and T3 in the animal disease model. Furthermore, the expression levels of genes and proteins in the JNK/c‑Jun signaling pathway and PLN expression levels were decreased, whereas the expression levels of sarcoplasmic reticulum calcium ATPase were increased after T3 treatment. These results indicated that T3 alleviated myocardial injury in SIC by inhibiting PLN expression and its phosphorylation, which may be related to the JNK/c‑Jun signaling pathway. Accordingly, PLN may have clinical diagnostic value in patients with SIC.

Methylprednisolone alleviates lung injury in sepsis by regulating miR-151-5p/USP38 pathway

BACKGROUND

Acute lung injury (ALI) is manifested by increased blood vessel permeability within the lungs and subsequent impairment of alveolar gas exchange. Methylprednisolone (MP) is commonly used as a treatment for ALI to reduce inflammation, yet its molecular mechanism remains unclear. This study aims to explore the underlying mechanisms of MP on ALI in a model induced by lipopolysaccharide (LPS).

MATERIAL AND METHODS

The proliferation, viability, apoptosis, and miR-151-5p expression of alveolar type II epithelial cells (AECII) were detected using the cell EdU assay, Annexin V/PI Apoptosis Kit, counting kit-8 (CCK-8) assay, and RT-qPCR. Western blot analysis was used to detect the Usp38 protein level. IL-6 and TNF-α were measured by ELISA. The combination of miR-151-5p and USP38 was determined by chromatin immunoprecipitation (ChIP)-PCR and dual-luciferase reporter assay.

RESULTS

MP greatly improved pulmonary function in vivo, reduced inflammation, and promoted the proliferation of the alveolar type II epithelial cells (AECII) in vitro. By comparing the alterations of microRNAs in lung tissues between MP treatment and control groups, we found that miR-151-5p exhibited a significant increase after LPS-treated AECII, but decreased after MP treatment. Confirmed by a luciferase reporter assay, USP38, identified as a downstream target of miR-151-5p, was found to increase after MP administration. Inhibition of miR-151-5p or overexpression of USP38 in AECII significantly improved the anti-inflammatory, anti-apoptotic, and proliferation-promotive effects of MP.

CONCLUSION

In summary, our data demonstrated that MP alleviates the inflammation and apoptosis of AECII induced by LPS, and promotes the proliferation of AECII partially via miR-151-5p suppression and subsequent USP38 activation.

The roles of Braun Lipoprotein in inducing tolerance of bovine endometrium infected by Escherichia coli

Escherichia coli (E. coli), a Gram-negative bacterium, is the primary pathogen responsible for endometritis in dairy cattle. The outer membrane components of E. coli, namely lipopolysaccharide (LPS) and bacterial lipoprotein, have the capacity to trigger the host's innate immune response through pattern recognition receptors (PRRs). Tolerance to bacterial cell wall components, including LPS, may play a crucial role as an essential regulatory mechanism during bacterial infection. However, the precise role of Braun lipoprotein (BLP) tolerance in E. coli-induced endometritis in dairy cattle remains unclear. In this study, we aimed to investigate the impact of BLP on the regulation of E. coli infection-induced endometritis in dairy cattle. The presence of BLP was found to diminish the expression and release of proinflammatory cytokines (IL-8 and IL-6), while concurrently promoting the expression and release of the anti-inflammatory cytokine IL-10 in endometrial epithelial cells (EECs). Furthermore, BLP demonstrated the ability to impede the activation of MAPK (ERK and p38) and NF-κB (p65) signaling pathways, while simultaneously enhancing signaling through the STAT3 pathway in EECs. Notably, BLP exhibited a dual role, acting both as an activator of TLR2 and as a regulator of TLR2 activation in LPS- and E. coli-treated EECs. In E. coli-infected endometrial explants, the presence of BLP was noted to decrease the release of proinflammatory cytokines and the expression of HMGB1, while simultaneously enhancing the release of anti-inflammatory cytokines. Collectively, our findings provide evidence that the bacterial component BLP plays a protective role in E. coli-induced endometritis in dairy cattle.

NETs induce ferroptosis of endothelial cells in LPS-ALI through SDC-1/HS and downstream pathways

BACKGROUND

Extracellular neutrophil extracellular traps (NETs) play an important role in acute lung injury (ALI), but their mechanisms are still unclear. The aim of this study is to explore the effects of NETs on endothelial glycocalyx/HGF/cMET pathway and ferroptosis in ALI and elucidate their potential mechanisms.

METHODS

Plasma was collected from healthy and sepsis patients to test for differences in neutrophil elastase (NE) expression of NETs components. In addition, LPS-ALI mice and endothelial cell injury models were established, and NETs were disrupted by siPAD4 (a driver gene for NETs) and sivelestat (an inhibitor of the NETs component) in the mice and by sivelestat in the endothelial cell injury models, and the effects of NETs on the SDC-1/HS/HGF/cMET pathway were studied. To verify the relationship between NETs and ferroptosis, Fer1, a ferroptosis inhibitor, was added as a positive control to observe the effect of NETs on ferroptosis indicators.

RESULTS

The expression level of NE was significantly higher in the plasma of sepsis patients. In ALI mice, intervention in the generation of NETs reduced pulmonary vascular permeability, protected the integrity of SDC-1/HS and promoted the downstream HGF/cMET pathway. In addition, sivelestat also improved the survival rate of mice, decreased the serious degree of ferroptosis. In the endothelial cells, the results were consistent with those of the ALI mice.

CONCLUSION

The study indicates that inhibiting the production of NETs can protect the normal conduction of the SDC-1/HS/HGF/cMET signalling pathway and reduce the severity of ferroptosis.

miR-186-5p improves alveolar epithelial barrier function by targeting the wnt5a/β-catenin signaling pathway in sepsis-acute lung injury

BACKGROUND

Alveolar epithelial barrier dysfunction is one of the pathological features of sepsis-acute lung injury(ALI). However, the molecular mechanisms that regulate the function of alveolar epithelial barrier remain unclear. This study aimed to determine the regulatory role of miR-186-5p in alveolar epithelial barrier function in sepsis-ALI and its underlying molecular mechanism.

METHODS

We established sepsis-ALI models in vivo and in vitro, detected the miR-186-5p and wnt5a/β-catenin expressions, and observed the functional changes of the alveolar epithelial barrier by miR-186-5p overexpression. We used rescue experiments to clarify whether miR-186-5p works through wnt5a/β-catenin.

RESULTS

miR-186-5p expression was decreased, wnt5a expression was increased, and the wnt5a/β-catenin signaling pathway was activated in mouse lung tissues and A549 cells after inflammatory stimulation. miR-186-5p overexpression resulted in wnt5a/β-catenin signaling pathway inhibition, decreased apoptosis in A549 cells, improved alveolar epithelial barrier function, reduced lung tissue injury in ALI mice, decreased IL-6 and TNF-α levels, and increased claudin4 and ZO-1 expression. Using miRNA-related database prediction and dual-luciferase reporter gene analysis, the targeting relationship between miR-186-5p and wnt5a was determined. The protective effect produced by miR-186-5p overexpression on the alveolar barrier was reversed after the application of the wnt5a/β-catenin activator Licl.

CONCLUSION

Our experimental data suggest miR-186-5p targets the wnt5a/β-catenin pathway, thereby regulating alveolar epithelial barrier function. Furthermore, both miR-186-5p and wnt5a/β-catenin are potential therapeutic targets that could impact sepsis-ALI.

Correlation of potential diagnostic biomarkers (circulating miRNA and protein) of bipolar II disorder

OBJECTIVES

We previously identified certain peripheral biomarkers of bipolar II disorder (BD-II) including circulating miRNAs (miR-7-5p, miR-142-3p, miR-221-5p, and miR-370-3p) and proteins (Matrix metallopeptidase 9 (MMP9), phenylalanyl-tRNA synthetase subunit beta (FARSB), peroxiredoxin 2 (PRDX2), carbonic anhydrase 1 (CA-1), and proprotein convertase subtilisin/kexin type 9 (PCSK9)). We try to explore the connection between these biomarkers.

METHODS

We explored correlations between the peripheral levels of above circulating miRNAs and proteins in our previously collected BD-II (N = 96) patients and control (N = 115) groups. We further searched TargetScan and BioGrid websites to identify direct and indirect interactions between these protein-coding genes and circulating miRNAs.

RESULTS

In the BD-II group, we identified significant correlations between the miR-221-5p and CA-1 (rho = -0.323, P = 0.001), FARSB (rho = 0.251, P = 0.014), MMP-9 (rho = 0.313, P = 0.002) and PCSK9 (rho = 0.252, P = 0.014). The miR-370-3p also significantly correlated with FARSB expression (rho = 0.330, P = 0.001) and PCSK9 expression (rho = 0.221, P = 0.031) in the BD-II group. Our findings were in line with the modulating axis identified from TargetScan and BioGrid, miR-221-5p/CA-1/MMP9 and miR-370-3p/FARSB/PCSK9, suggesting their association with BD-II.

CONCLUSION

Our result supported that peripheral candidate miRNA and protein biomarkers may interact in BD-II. We concluded that miR-221-5p/CA-1/MMP9 and miR-370-3p/FARSB/PCSK9 axes might act a critical role in the pathomechanism of BD-II.

[Tea polyphenols ameliorates acute lung injury in septic mice by inhibiting NLRP3 inflammasomes]

OBJECTIVE

To investigate the mechanism of tea polyphenols (TP) for regulating NLRP3 inflammasomes and alleviating acute lung injury in septic mice.

METHODS

Sixty C57BL/6 mice were randomly assigned into sham-operated, cecal ligation and puncture (CLP) and CLP +TP treatment groups, and survival of the mice was recorded after modeling in each group. The lung wet/dry weight ratio and myeloperoxidase (MPO) activity were determined, and lung injury of the mice was evaluated using HE staining and acute lung injury score. The expressions of IL-1β, TNF-α, IL-6, NLRP3, caspase-1 p10, ASC, MPO, and caspase-8 in the lung tissue were detected using ELISA, Western blotting, or immunohistochemical staining. MDA and H2O2 levels in the lungs were detected to evaluate the level of oxidative stress. Immunofluorescence assay was used to investigate the co-localization of NLRP3 and NOX4.

RESULTS

The postoperative mortality rate at 72 h, lung wet/dry weight ratio, MPO level and acute lung injury scores were significantly lower in CLP+TP group than in CLP group (P < 0.05). Treatment with TP significantly reduced the expressions of NLRP3-related inflammatory factors (P < 0.05) and lowered MDA and H2O2 levels in the lung tissue of the septic mice (P < 0.05). Immunofluorescence co-staining showed a lower level of NOX4 and NLRP3 co-localization in CLP+TP group than in CLP group.

CONCLUSION

TP inhibits NLRP3 inflammasome-associated inflammation to alleviate CLP-induced acute lung injury in mice through a regulatory mechanism that inhibits NOX4 expression and reduces oxidative stress in the lung tissue.

Mogroside V alleviates inflammation response by modulating miR-21-5P/SPRY1 axis

Mogroside V (MV) is a natural sweetener extracted from the edible plant Siraitia grosvenorii that possesses anti-inflammatory bioactivity. It has been reported that microRNAs (miRNAs) play an important role in the inflammation response suppression by natural agents. However, whether the anti-inflammation effect of mogroside V is related to miRNAs and the underlying mechanism remains unclear. Our study aimed to identify the key miRNAs important for the anti-inflammation effect of MV and reveal its underlying mechanisms. Our results showed that MV effectively alleviated lung inflammation in ovalbumin-induced (OVA-induced) asthmatic mice. miRNA-seq and mRNA-seq combined analysis identified miR-21-5p as an important miRNA for the inflammation inhibition effect of MV and it predicted SPRY1 to be a target gene of miR-21-5p. We found that MV significantly inhibited the production of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-2 (IL-2), interleukin-6 (IL-6), and nitric oxide (NO), as well as the protein expression of p-P65/P65, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS) in OVA-induced asthmatic mice and LPS-treated RAW 264.7 cells. Moreover, the release of ROS increased in LPS-stimulated RAW 264.7 cells but was mitigated by MV pretreatment. In the meantime, the expression of miR-21-5p was decreased by MV, leading to an increase in the expression of SPRY1 in RAW 264.7 cells. Furthermore, miR-21-5p overexpression or SPRY1 knockdown reversed MV's protective effect on inflammatory responses. Conversely, miR-21-5p inhibition or SPRY1 overexpression enhanced MV's effect on inflammatory responses in LPS-exposed RAW 264.7 cells. Therefore, the significant protective effect of mogroside V on inflammation response is related to the downregulation of miR-21-5p and upregulation of SPRY1 in vitro and in vivo, MiR-21-5p/SPRY1 may be novel therapeutic targets of MV for anti-inflammation treatment.

Expression profile of mRNAs and miRNAs related to mitogen-activated kinases in HaCaT cell culture treated with lipopolysaccharide a and adalimumab

Studies indicate that mitogen-activated protein kinases (MAPKs) exhibit activation and overexpression within psoriatic lesions. This study aimed to investigate alterations in the expression patterns of genes encoding MAPKs and microRNA (miRNA) molecules that potentially regulate their expression in human adult low-calcium high-temperature (HaCaT) keratinocytes when exposed to bacterial lipopolysaccharide A (LPS) and adalimumab. HaCaT cells underwent treatment with 1 µg/mL LPS for 8 hours, followed by treatment with 8 µg/mL adalimumab for 2, 8, or 24 hours. Untreated cells served as controls. The molecular analysis involved microarray, quantitative real-time polymerase chain reaction (RTqPCR), and enzyme-linked immunosorbent assay (ELISA) analyses. Changes in the expression profile of seven mRNAs: dual specificity phosphatase 1 (DUSP1), dual specificity phosphatase 3 (DUSP3), dual specificity phosphatase 4 (DUSP4), mitogen-activated protein kinase 9 (MAPK9), mitogen-activated protein kinase kinase kinase 2 (MAP3K2), mitogen-activated protein kinase kinase 2 (MAP2K2), and MAP kinase-activated protein kinase 2 (MAPKAPK2, also known as MK2) in cell culture exposed to LPS or LPS and the drug compared to the control. It was noted that miR-34a may potentially regulate the activity of DUSP1, DUSP3, and DUSP4, while miR-1275 is implicated in regulating MAPK9 expression. Additionally, miR-382 and miR-3188 are potential regulators of DUSP4 levels, and miR-200-5p is involved in regulating MAPKAPK2 and MAP3K2 levels. Thus, the analysis showed that these mRNA molecules and the proteins and miRNAs they encode appear to be useful molecular markers for monitoring the efficacy of adalimumab therapy.

Gene expression profile of mitogen-activated kinases and microRNAs controlling their expression in HaCaT cell culture treated with lipopolysaccharide A and cyclosporine A

Studies indicate that mitogen-activated protein kinases (MAPKs) are activated and overexpressed in psoriatic lesions. The aim of the study was to assess changes in the expression pattern of genes encoding MAPKs and microRNA (miRNA) molecules potentially regulating their expression in human adult low-calcium high-temperature (HaCaT) keratinocytes exposed to bacterial lipopolysaccharide A (LPS) and cyclosporine A (CsA). HaCaT cells were treated with 1 µg/mL LPS for 8 h, followed by treatment with 100 ng/mL cyclosporine A for 2, 8, or 24 h. Untreated cells served as controls. The molecular analysis consists of microarray, quantitative real-time polymerase chain reaction, and enzyme-linked immunosorbent assay analyses. The statistical analysis of the obtained results was performed using Transcriptome Analysis Console and STATISTICA 13.5 PL with the statistical significance threshold of p < 0.05. Changes in the expression profile of six mRNAs: dual-specificity phosphatase 1 (DUSP1), dual-specificity phosphatase 4 (DUSP4), mitogen-activated protein kinase kinase 2 (MAP2K2), mitogen-activated protein kinase kinase 7 (MAP2K7), mitogen-activated protein kinase kinase kinase 2 (MAP3K2) and mitogen-activated protein kinase 9 (MAPK9) in cell culture exposed to LPS or LPS and the drug compared to the control. We observed that under the LPS and cyclosporine treatment, the expression o/ miR-34a, miR-1275, miR-3188, and miR-382 changed significantly (p < 0.05). We demonstrated a potential relationship between DUSP1 and miR-34a; DUSP4 and miR-34a, miR-382, and miR-3188; MAPK9 and miR-1275, MAP2K7 and mir-200-5p; MAP3K2 and mir-200-5p, which may be the subject of further research in the context of psoriasis.

Signaling pathways and potential therapeutic targets in acute respiratory distress syndrome (ARDS)

Acute respiratory distress syndrome (ARDS) is a common condition associated with critically ill patients, characterized by bilateral chest radiographical opacities with refractory hypoxemia due to noncardiogenic pulmonary edema. Despite significant advances, the mortality of ARDS remains unacceptably high, and there are still no effective targeted pharmacotherapeutic agents. With the outbreak of coronavirus disease 19 worldwide, the mortality of ARDS has increased correspondingly. Comprehending the pathophysiology and the underlying molecular mechanisms of ARDS may thus be essential to developing effective therapeutic strategies and reducing mortality. To facilitate further understanding of its pathogenesis and exploring novel therapeutics, this review provides comprehensive information of ARDS from pathophysiology to molecular mechanisms and presents targeted therapeutics. We first describe the pathogenesis and pathophysiology of ARDS that involve dysregulated inflammation, alveolar-capillary barrier dysfunction, impaired alveolar fluid clearance and oxidative stress. Next, we summarize the molecular mechanisms and signaling pathways related to the above four aspects of ARDS pathophysiology, along with the latest research progress. Finally, we discuss the emerging therapeutic strategies that show exciting promise in ARDS, including several pharmacologic therapies, microRNA-based therapies and mesenchymal stromal cell therapies, highlighting the pathophysiological basis and the influences on signal transduction pathways for their use.

Liver proteomic analysis reveals the key proteins involved in host immune response to sepsis

Background

Sepsis is a serious infection-induced response in the host, which can result in life-threatening organ dysfunction. It is of great importance to unravel the relationship between sepsis and host immune response and its mechanisms of action. Liver is one of the most vulnerable organs in sepsis, however, the specific pathogenesis of septic liver injury has not been well understood at the protein level.

Methods

A total of 12 healthy Sprague-Dawley (SD) male rats aged from 6 to 8 weeks were adaptively housed in individual cages in the specific pathogen free animal room. These lab rats were grouped into two groups: treatment (N = 9) and control (N = 3) groups; only three mice from the treatment group survived and were used for subsequent experiments. A TMT-based proteomic analysis for liver tissue was performed in the septic rat model.

Results

A total of 37,012 unique peptides were identified, and then 6,166 proteins were determined, among which 5,701 were quantifiable. Compared to the healthy control group, the septic rat group exhibited 162 upregulated and 103 downregulated differentially expressed proteins (DEPs). The upregulated and downregulated DEPs were the most significantly enriched into the complement and coagulation cascades and metabolic pathways. Protein-protein interaction (PPI) analysis further revealed that the upregulated and downregulated DEPs each clustered in a PPI network. Several highly connected upregulated and downregulated DEPs were also enriched into the complement and coagulation cascades pathways and metabolic pathways, respectively. The parallel reaction monitoring (PRM) results of the selected DEPs were consistent with the results of the TMT analysis, supporting the proteomic data.

Conclusion

Our findings highlight the roles of complement and coagulation cascades and metabolic pathways that may play vital roles in the host immune response. The DEPs may serve as clinically potential treatment targets for septic liver injury.

Personalized medicine using omics approaches in acute respiratory distress syndrome to identify biological phenotypes

In the last decade, research on acute respiratory distress syndrome (ARDS) has made considerable progress. However, ARDS remains a leading cause of mortality in the intensive care unit. ARDS presents distinct subphenotypes with different clinical and biological features. The pathophysiologic mechanisms of ARDS may contribute to the biological variability and partially explain why some pharmacologic therapies for ARDS have failed to improve patient outcomes. Therefore, identifying ARDS variability and heterogeneity might be a key strategy for finding effective treatments. Research involving studies on biomarkers and genomic, metabolomic, and proteomic technologies is increasing. These new approaches, which are dedicated to the identification and quantitative analysis of components from biological matrixes, may help differentiate between different types of damage and predict clinical outcome and risk. Omics technologies offer a new opportunity for the development of diagnostic tools and personalized therapy in ARDS. This narrative review assesses recent evidence regarding genomics, proteomics, and metabolomics in ARDS research.

Modes of action and diagnostic value of miRNAs in sepsis

Sepsis is a clinical syndrome defined as a dysregulated host response to infection resulting in life-threatening organ dysfunction. Sepsis is a major public health concern associated with one in five deaths worldwide. Sepsis is characterized by unbalanced inflammation and profound and sustained immunosuppression, increasing patient susceptibility to secondary infections and mortality. microRNAs (miRNAs) play a central role in the control of many biological processes, and deregulation of their expression has been linked to the development of oncological, cardiovascular, neurodegenerative and metabolic diseases. In this review, we discuss the role of miRNAs in sepsis pathophysiology. Overall, miRNAs are seen as promising biomarkers, and it has been proposed to develop miRNA-based therapies for sepsis. Yet, the picture is not so straightforward because of the versatile and dynamic features of miRNAs. Clearly, more research is needed to clarify the expression and role of miRNAs in sepsis, and to promote the use of miRNAs for sepsis management.