MiR-802 alleviates lipopolysaccharide-induced acute lung injury by targeting Peli2

Advances in acute respiratory distress syndrome: focusing on heterogeneity, pathophysiology, and therapeutic strategies

In recent years, the incidence of acute respiratory distress syndrome (ARDS) has been gradually increasing. Despite advances in supportive care, ARDS remains a significant cause of morbidity and mortality in critically ill patients. ARDS is characterized by acute hypoxaemic respiratory failure with diffuse pulmonary inflammation and bilateral edema due to excessive alveolocapillary permeability in patients with non-cardiogenic pulmonary diseases. Over the past seven decades, our understanding of the pathology and clinical characteristics of ARDS has evolved significantly, yet it remains an area of active research and discovery. ARDS is highly heterogeneous, including diverse pathological causes, clinical presentations, and treatment responses, presenting a significant challenge for clinicians and researchers. In this review, we comprehensively discuss the latest advancements in ARDS research, focusing on its heterogeneity, pathophysiological mechanisms, and emerging therapeutic approaches, such as cellular therapy, immunotherapy, and targeted therapy. Moreover, we also examine the pathological characteristics of COVID-19-related ARDS and discuss the corresponding therapeutic approaches. In the face of challenges posed by ARDS heterogeneity, recent advancements offer hope for improved patient outcomes. Further research is essential to translate these findings into effective clinical interventions and personalized treatment approaches for ARDS, ultimately leading to better outcomes for patients suffering from ARDS.

Genetic analysis of diagnostic and therapeutic potential for ferroptosis in postoperative sepsis

BACKGROUND

Ferroptosis is a new form of iron-dependent cell death that is closely associated with sepsis. However, few studies have investigated the diagnostic and therapeutic potential for ferroptosis-related genes (FRGs) among postoperative sepsis.

METHODS

The GSE131761 dataset was used to identify differentially expressed FRGs (DE-FRGs). KEGG and GO analyses were subsequently performed. LASSO and SVM-RFE methods were applied for identifying genetic biomarkers for sepsis. Gene set enrichment analysis (GSEA) and gene set variation analysis (GSVA) were applied for exploring the biological properties of the DEGs. CIBERSORT was applied to analyse immune cell infiltration. DGldb was employed for predicting potential target drugs for the DEGs. Competing endogenous RNA (ceRNA) networks were constructed to analyse the regulatory patterns of the DEGs. The expression of hub genes was validated based on GSE26440 dataset. The bioinformatics analysis was carried out with R software (version 4.1.2). Blood from sepsis patients and healthy controls was collected and the expression of hub genes was experimentally verified by real-time quantitative polymerase chain reaction (RT-qPCR).

RESULTS

38 sepsis-associated DE-FRGs were assessed via Gene Expression Omnibus (GEO) and Ferroptosis database (FerrDb), and the gene function analysis showed that they were closely related to inflammatory response and autophagy regulation. Subsequently, SVM-RFE and LASSO methods determined 7 marker genes. GSEA suggested that these marker genes may be involved in regulating several biological pathways. Furthermore, 52 gene-targeted drugs were identified in this study, the vast majority of which were associated with MAPK14. CIBERSORT analysis suggested that SLC38A1, MGST1, and MAPK14 may be involved in immune microenvironment alterations. We revealed the potential complex regulatory relationship by constructing a ceRNA network based on marker genes. Finally, 6 genes were validated in the validation set, with 5 of them further confirmed through RT-qPCR.

CONCLUSION

Seven genes associated with ferroptosis are screened from postoperative sepsis samples. The expression of these genes has high diagnostic validity for sepsis and may serve as potential diagnostic biomarkers. This study gives an entrance point to uncover the underlying mechanisms of sepsis.

Immunohistochemical and molecular study for differential diagnosis between freshwater and saltwater drowning

The postmortem identification of drowning in the field of forensic medicine is difficult due to unspecific autopsy findings, and usually, it is a "diagnosis of exclusion". A model of drowning in salt and fresh water was established to discuss the postmortem changes after drowning and the differences between saltwater drowning (SWD) and freshwater drowning (FWD). The organs (brain and 'lung) of 30 rats were extracted at three-time points (0 h, 24 h, and 48 h) after drowning. The histopathological, immunohistochemical,l, and molecular changes in the lung and brain of rats at different time points were investigated. Results show no significant difference in pathological findings between fresh and saltwater drowning. Casp3, JNK, and ERK all showed a rise in their postmortem expression in a time-dependent way; the expression of these three genes is much greater in cases of saltwater drowning compared to cases of freshwater drowning. So, it is concluded that after 24 h and 48 h from death, potent cellular oxidative stress occurred and caused the upregulation of the studied genes.

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.

Circulating exosomes from brain death and cardiac death donors have distinct molecular and immunologic properties: A pilot study

BACKGROUND AND AIMS

Comparison of donation after brain death (DBD) and donation after cardiac death (DCD) lung tissue before transplantation have demonstrated activation of pro-inflammatory cytokine pathway in DBD donors. The molecular and immunological properties of circulating exosomes from DBD and DCD donors were not previously described.

METHODS

We collected plasma from 18 deceased donors (12 DBD and six DCD). Cytokines were analyzed by 30-Plex luminex Panels. Exosomes were analyzed for liver self-antigen (SAg), Transcription Factors and HLA class II (HLA-DR/DQ) using western blot. C57BL/6 animals were immunized with isolated exosomes to determine strength and magnitude of immune responses. Interferon (IFN)-γ and tumor necrosis factor-α producing cells were quantified by ELISPOT, specific antibodies to HLA class II antigens were measured by ELISA RESULTS: We demonstrate increased plasma levels of IFNγ, EGF, EOTAXIN, IP-10, MCP-1, RANTES, MIP-β, VEGF, and interleukins - 6/8 in DBD plasma versus DCD. MiRNA isolated from exosome of DBD donors demonstrated significant increase in miR-421, which has been reported to correlate with higher level of Interleukin-6. Higher levels of liver SAg Collagen III (p = .008), pro-inflammatory transcription factors (NF-κB, p < .05; HIF1α, p = .021), CIITA (p = .011), and HLA class II (HLA-DR, p = .0003 and HLA-DQ, p = .013) were detected in exosomes from DBD versus DCD plasma. The circulating exosomes isolated from DBD donors were immunogenic in mice and led to the development of Abs to HLA-DR/DQ.

CONCLUSIONS

This study provides potential new mechanisms by which DBD organs release exosomes that can activate immune pathways leading to cytokine release and allo-immune response.

Impact of intestinal microenvironments in obesity and bariatric surgery on shaping macrophages

Obesity is associated with alterations in tissue composition, systemic cellular metabolism, and low-grade chronic inflammation. Macrophages are heterogenous innate immune cells ubiquitously localized throughout the body and are key components of tissue homeostasis, inflammation, wound healing, and various disease states. Macrophages are highly plastic and can switch their phenotypic polarization and change function in response to their local environments. Here, we discuss how obesity alters the intestinal microenvironment and potential key factors that can influence intestinal macrophages as well as macrophages in other organs, including adipose tissue and hematopoietic organs. As bariatric surgery can induce metabolic adaptation systemically, we discuss the potential mechanisms through which bariatric surgery reshapes macrophages in obesity.

A genome-wide landscape of mRNAs, lncRNAs, circRNAs and miRNAs during intramuscular adipogenesis in cattle

Background

Intramuscular preadipocyte differentiation plays a critical role in bovine intramuscular fat (IMF) deposition. However, the roles of different RNAs, including mRNAs, circRNAs, lncRNAs and miRNAs, in regulating the adipogenic differentiation of intramuscular preadipocytes remain largely unclear.

Results

In the present study, a whole transcriptome sequencing and analysis, including the analysis of mRNAs, circRNAs, lncRNAs and miRNAs, during different differentiation stages (0, 3, 6, and 9 d) of intramuscular preadipocytes from Qinchuan cattle was performed. All samples were prepared with 3 biological replicates. Here, a total of 27,153 mRNAs, 14,070 circRNAs, 7035 lncRNAs, and 427 miRNAs were annotated. Among them, we identified 4848 differentially expressed mRNAs (DEMs), 181 DE circRNAs (DECs), 501 DE lncRNAs (DELs) and 77 DE miRNAs (DEmiRs) between 0 d and other differentiation days (3, 6, and 9 d). GO and KEGG functional enrichment analyses showed that these differentially expressed genes were mainly enriched in cell differentiation, fat metabolism and adipogenesis-related pathways. Furthermore, weighted gene coexpression network analysis (WGCNA) and co-expression network analysis screened out multiple important mRNAs, circRNAs and lncRNAs related to intramuscular adipogenesis. Based on the competing endogenous RNA (ceRNA) regulatory mechanism, we finally identified 24 potential ceRNA networks and 31 potential key genes, including FOXO1/miR-330/circRNA2018/MSTRG.20301, GPAM/miR-27b/ciRNA489 and SESN3/miR-433/circRNA2627MSTRG.20342.

Conclusions

This study provides new insights into the differential expression patterns of different transcript types (i.e., mRNAs, circRNAs, lncRNAs and miRNAs) in intramuscular preadipocyte differentiation. Our findings provide data support for studying the molecular mechanism of key mRNAs and noncoding RNAs in IMF deposition, and provide new candidate markers for the molecular breeding of beef cattle.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-022-08911-z.

Expression of MicroRNAs in Sepsis-Related Organ Dysfunction: A Systematic Review

Sepsis is a critical condition characterized by increased levels of pro-inflammatory cytokines and proliferating cells such as neutrophils and macrophages in response to microbial pathogens. Such processes lead to an abnormal inflammatory response and multi-organ failure. MicroRNAs (miRNA) are single-stranded non-coding RNAs with the function of gene regulation. This means that miRNAs are involved in multiple intracellular pathways and thus contribute to or inhibit inflammation. As a result, their variable expression in different tissues and organs may play a key role in regulating the pathophysiological events of sepsis. Thanks to this property, miRNAs may serve as potential diagnostic and prognostic biomarkers in such life-threatening events. In this narrative review, we collect the results of recent studies on the expression of miRNAs in heart, blood, lung, liver, brain, and kidney during sepsis and the molecular processes in which they are involved. In reviewing the literature, we find at least 122 miRNAs and signaling pathways involved in sepsis-related organ dysfunction. This may help clinicians to detect, prevent, and treat sepsis-related organ failures early, although further studies are needed to deepen the knowledge of their potential contribution.

microRNA-145-5p attenuates acute lung injury via targeting ETS2

The protective effect of microRNA (miR)-145-5p in acute lung injury (ALI) has been discovered previously. Thus, in this study, we attempted to further investigate the mechanism of miR-145-5p in ALI through the downstream E26 transformation-specific proto-oncogene 2 (ETS2)/transforming growth factor β1 (TGF-β1)/Smad pathway. A lipopolysaccharide (LPS)-induced ALI rat model was established. The expression of miR-145-5p in ALI rat lung tissues was up-regulated. Afterward, pathological damage in the lung tissue, the wet/dry (W/D) ratio, apoptosis, and serum inflammatory factor contents were observed. miR-145-5p, ETS2, TGF-β1, Smad2/3, and phosphorylated Smad2/3 levels were measured in rats. miR-145-5p expression was down-regulated, ETS2 expression was up-regulated, and the TGF-β1/Smad pathway was activated in LPS-exposed rats. Overexpression of miR-145-5p inactivated the TGF-β1/Smad pathway and attenuated ALI, as reflected by relieved pathological damage, a decreased W/D ratio, reduced apoptosis, and suppressed inflammatory response. In contrast, loss of miR-145-5p or elevated ETS2 levels worsened ALI and activated the TGF-β1/Smad pathway. Moreover, elevation of ETS2 diminished miR-145-5p-mediated protection against ALI. Evidently, miR-145-5p negatively regulates ETS2 expression and inactivates the TGF-β1/Smad pathway to ameliorate ALI in rats.

MicroRNAs: Important Regulatory Molecules in Acute Lung Injury/Acute Respiratory Distress Syndrome

Acute lung injury (ALI)/acute respiratory distress syndrome (ARDS) is an overactivated inflammatory response caused by direct or indirect injuries that destroy lung parenchymal cells and dramatically reduce lung function. Although some research progress has been made in recent years, the pathogenesis of ALI/ARDS remains unclear due to its heterogeneity and etiology. MicroRNAs (miRNAs), a type of small noncoding RNA, play a vital role in various diseases. In ALI/ARDS, miRNAs can regulate inflammatory and immune responses by targeting specific molecules. Regulation of miRNA expression can reduce damage and promote the recovery of ALI/ARDS. Consequently, miRNAs are considered as potential diagnostic indicators and therapeutic targets of ALI/ARDS. Given that inflammation plays an important role in the pathogenesis of ALI/ARDS, we review the miRNAs involved in the inflammatory process of ALI/ARDS to provide new ideas for the pathogenesis, clinical diagnosis, and treatment of ALI/ARDS.

Extracellular citrate serves as a DAMP to activate macrophages and promote LPS-induced lung injury in mice

Citrate has a prominent role as a substrate in cellular energy metabolism. Recently, citrate has been shown to drive inflammation. However, the role of citrate in lipopolysaccharide (LPS)-induced acute lung injury (ALI) remains unclear. Here, we aimed to clarify whether extracellular citrate aggravated the LPS-induced ALI and the potential mechanism. Our findings demonstrated that extracellular citrate aggravated the pathological lung injury induced by LPS in mice, characterized by up-regulation of pro-inflammatory factors and over-activation of NACHT, LRR, and PYD domains-containing protein 3 (NLRP3) inflammasome in the lungs. In vitro, we found that citrate treatment significantly augmented the expression of NLRP3 and pro-IL-1β and enhanced the translocation of NF-κB/p65 into the nucleus. Furthermore, extracellular citrate plus adenosine-triphosphate (ATP) significantly increased the production of reactive oxygen species (ROS) in primary murine macrophages. Inhibiting the production of ROS with a ROS scavenger N-acetyl-L-cysteine (NAC) attenuated the activation of NLRP3 inflammasome. Altogether, we conclude that extracellular citrate may serve as a damage-associated molecular pattern (DAMP) and aggravates LPS-induced ALI by activating the NLRP3 inflammasome.

miR-128-3p reduced acute lung injury induced by sepsis via targeting PEL12

Objective

Acute lung injury (ALI) caused by sepsis is clinically a syndrome, which is featured by damage to the alveolar epithelium and endothelium. In this study, we employed mice models of cecal ligation and puncture (CLP) and primary mice pulmonary microvascular endothelial cells (MPVECs) in vitro to investigate the effect of miR-128-3p in ALI caused by sepsis.

Methods

miR-128-3p agomir or randomized control were injected into adult male C57BL/6 mice 1 week before the CLP surgery. We used miR-128-3p agomir or scrambled control to transfect MPVECs and then employed lipopolysaccharide (LPS) stimulation on the cells. Pellino homolog 2 (PELI2) was predicted to be a direct target of miR-128-3p via luciferase reporter assay. MPVECs were cotransfected with lentiviral vector that expressed PELI2 (or empty vector) as well as miR-128-3p-mimics 1 day before LPS stimulation in rescue experiment. Transcriptional activity of caspase-3, cell apoptosis rate, and the expression levels of miR-128-3p, interleukin-1β (IL-1β), interleukin-6 (IL-6), and PELI2 were analyzed.

Results

Compared with the sham group, the lung of mice in the CLP group showed pulmonary morphological abnormalities, and the expression of IL-6 and IL-1β, caspase-3 activity, and apoptosis rate were significantly upregulated in the CLP group. Inflammatory factor levels and apoptosis rate were also significantly induced by LPS stimulation on MPVECs. Upregulation of miR-128-3p effectively inhibited sepsis-induced ALI, apoptosis as well as inflammation. miR-128-3p also played a role in antiapoptosis and anti-inflammation in MPVECs with LPS treatment. PEL12 upregulation in MPVECs alleviated miR-128-3p-induced caspase-3 activity inhibition and pro-inflammatory factor production.

Conclusions

miR-128-3p enabled to alleviate sepsis-induced ALI by inhibiting PEL12 expression, indicating a novel treatment strategy of miR-128-3p for sepsis-induced ALI.

Long non-coding RNA NEAT1 promotes lipopolysaccharide-induced acute lung injury by regulating miR-424-5p/MAPK14 axis

BACKGROUND

Many long non-coding RNAs (lncRNAs) have been suggested to play critical roles in acute lung injury (ALI) pathogenesis, including lncRNA nuclear enriched abundant transcript 1 (NEAT1).

OBJECTIVE

We aimed to further elucidate the functions and molecular mechanism of NEAT1 in ALI.

METHODS

Human pulmonary alveolar epithelial cells (HPAEpiCs) stimulated by lipopolysaccharide (LPS) were served as a cellular model of ALI. Cell viability and cell apoptosis were determined by cell counting kit-8 (CCK-8) assay and flow cytometry, respectively. The expression of NEAT1, microRNA-424-5p (miR-424-5p), and mitogen-activated protein kinase 14 (MAPK14) was measured by quantitative real-time polymerase chain reaction (qRT-PCR) or western blot analysis. Caspase activity was determined by caspase activity kit. The inflammatory responses were evaluated using enzyme-linked immunosorbent assay (ELISA). The oxidative stress factors were analyzed by corresponding kits.

RESULTS

NEAT1 was upregulated in LPS-stimulated HPAEpiCs. NEAT1 knockdown weakened LPS-induced injury by inhibiting apoptosis, inflammation and oxidative stress in HPAEpiCs. Moreover, miR-424-5p was a direct target of NEAT1, and its knockdown reversed the effects caused by NEAT1 knockdown in LPS-induced HPAEpiCs. Furthermore, MAPK14 was a downstream target of miR-424-5p, and its overexpression attenuated the effects of miR-424-5p on reduction of LPS-induced injury in HPAEpiCs. Besides, NEAT1 acted as a sponge of miR-424-5p to regulate MAPK14 expression.

CONCLUSION

NEAT1 knockdown alleviated LPS-induced injury of HPAEpiCs by regulating miR-424-5p/MAPK14 axis, which provided a potential therapeutic target for the treatment of ALI.

miR‑26a‑5p alleviates lipopolysaccharide‑induced acute lung injury by targeting the connective tissue growth factor

The aim of the present study was to investigate the regulatory functions of microRNA (miR)‑26a‑5p on lipopolysaccharide (LPS)‑induced acute lung injury (ALI) and its molecular mechanisms. The role of miR‑26a‑5p on an ALI mouse model was evaluated by examining the histological changes, wet/dry (W/D) ratio, myeloperoxidase (MPO) activity, malondialdehyde (MDA) expression levels in lung tissues and the survival of ALI mice. Moreover, the protein concentration and the number of neutrophils and lymphocytes in bronchoalveolar lavage fluid (BALF) was analyzed. To explore the effect of miR‑26a‑5p on inflammatory responses and apoptosis, the expression levels of tumour necrosis factor‑α (TNF‑α), interleukin (IL)‑1β and IL‑6 and apoptosis were measured by ELISA, terminal deoxynucleotidyl transferase‑mediated dUTP nick end labelling staining and flow cytometry in BALF, A549 cells and lung tissues. B‑cell lymphoma‑2 (Bcl‑2), Bax and cleaved caspase‑3 in lung tissues were measured by western blotting and reverse transcription‑quantitative PCR. Connective tissue growth factor (CTGF) was predicted as a direct target of miR‑26a‑5p using dual luciferase reporter assay. The present study sought to determine whether CTGF overexpression reversed the effect of miR‑26a‑5p on apoptosis and inflammatory responses in LPS‑induced A549 cells. The data revealed that miR‑26a‑5p overexpression ameliorated LPS‑induced ALI, which was implicated by fewer histopathological changes, W/D ratio, apoptosis in lung tissues and the survival of ALI mice. Moreover, miR‑26a‑5p overexpression alleviated LPS‑induced inflammatory responses in ALI mice via the reduction of total protein, neutrophil and lymphocyte counts and the expression levels of TNF‑α, IL‑1β, IL‑6, MDA and MPO activity in BALF. Similarly, miR‑26a‑5p overexpression decreased apoptosis and the expression of TNF‑α, IL‑1β and IL‑6 in LPS‑induced A549 cells. CTGF was a direct target of miR‑26a‑5p. CTGF overexpression reversed the effect of miR‑26a‑5p on cell apoptosis and inflammatory responses in LPS‑induced A549 cells. The present study demonstrated that miR‑26a‑5p could attenuate lung inflammation and apoptosis in LPS‑induced ALI by targeting CTGF.

Hypertrophic Adipocyte-Derived Exosomal miR-802-5p Contributes to Insulin Resistance in Cardiac Myocytes Through Targeting HSP60

OBJECTIVE

This study aimed to elucidate the mechanism by which hypertrophic adipocytes regulate insulin signaling in cardiac myocytes.

METHODS

Palmitate was used to induce hypertrophic 3T3-L1 adipocytes. Exosomes were purified from normal control or hypertrophic 3T3-L1 adipocyte-associated conditioned medium. Exosome-exposed neonatal rat ventricular myocytes were stimulated with insulin to investigate the effects of exosomes on insulin signaling. Small interfering RNA techniques were used to downregulate protein levels, and their efficiency was evaluated by Western blot.

RESULTS

Hypertrophic adipocyte-derived exosomes highly expressed miR-802-5p. Insulin sensitivity of neonatal rat ventricular myocytes was negatively regulated by miR-802-5p. TargetScan and luciferase reporter assays revealed that heat shock protein 60 (HSP60) was a direct target of miR-802-5p. HSP60 silencing was found to induce insulin resistance and to mitigate the insulin-sensitizing effects of adiponectin. In addition, HSP60 depletion significantly increased the expression levels of C/EBP-homologous protein and enhanced oxidative stress, accompanied by the increases in the phosphorylation of JNK and IRS-1 Ser307. Moreover, the effects of HSP60 knockdown on C/EBP-homologous protein and oxidative stress were abolished by the inhibition of either miR-802-5p or endocytosis.

CONCLUSIONS

Hypertrophic adipocyte-derived exosomal miR-802-5p caused cardiac insulin resistance through downregulating HSP60. These findings provide a novel mechanism by which epicardial adipose tissue impairs cardiac function.

Pulmonary Neutrophilic Inflammation and Noncommunicable Diseases: Pathophysiology, Redox Mechanisms, Biomarkers, and Therapeutics

Significance: Pulmonary neurophilic inflammation (PNI) is the homing and activation of neutrophil with damage to the microvasculature. This process is involved in pulmonary damage in patients exposed to airborne pollutants (exogenous stressors) and also to systemic inflammation/oxidative stress (endogenous stressors) associated with noncommunicable diseases (NCDs). Recent Advances: PNI is an important trigger of the early onset and progression of NCD in susceptible patients exposed to airborne pollutants. Irritation of the lung microvasculature by exogenous and endogenous stressors causes PNI. Circulating endogenous stressors in NCD can cause PNI. Critical Issues: Air pollution-triggered PNI causes increased circulating endogenous stressors that can trigger NCD in susceptible patients. Systemic inflammation/oxidative stress associated with NCD can cause PNI. Inflammation/end-oxidation products of macromolecules are also potential biomarkers and therapeutic targets for NCD-triggered PNI- and PNI-triggered NCD. Future Directions: Understanding the molecular mechanism of PNI triggered by exogenous or endogenous stressors will help explain the early onset of NCD in susceptible patients exposed to air pollution. It can also help undercover biomarkers and mechanism-based therapeutic targets in air pollutant-triggered PNI, PNI-triggered NCD, and NCD-triggered PNI.

Inhibition of miR-103a-3p suppresses lipopolysaccharide-induced sepsis and liver injury by regulating FBXW7 expression

Inflammation, apoptosis, and oxidative stress are involved in septic liver dysfunction. Herein, the role of miR‐103a‐3p/FBXW7 axis in lipopolysaccharides (LPS)‐induced septic liver injury was investigated in mice. Hematoxylin‐eosin staining was used to evaluate LPS‐induced liver injury. Quantitative real‐time polymerase chain reaction was performed to determine the expression of microRNA (miR) and messenger RNA, and western blot analysis was conducted to examine the protein levels. Dual‐luciferase reporter assay was used to confirm the binding between miR‐103a‐3p and FBXW7. Both annexin V‐fluoresceine isothiocyanate/propidium iodide staining and caspase‐3 activity were employed to determine cell apoptosis. First, miR‐103a‐3p was upregulated in the septic serum of mice and patients with sepsis, and miR‐103a‐3p was elevated in the septic liver of LPS‐induced mice. Then, interfering miR‐103a‐3p significantly decreased apoptosis by suppressing Bax expression and upregulating Bcl‐2 levels in LPS‐induced AML12 and LO2 cells, and septic liver of mice. Furthermore, inhibition of miR‐103a‐3p repressed LPS‐induced inflammation by downregulating the expression of tumor necrosis factor, interleukin 1β, and interleukin 6 in vitro and in vivo. Meanwhile, interfering miR‐103a‐3p obviously attenuated LPS‐induced overactivation of oxidation via promoting expression of antioxidative enzymes, including catalase, superoxide dismutase, and glutathione in vitro and in vivo. Moreover, FBXW7 was a target of miR‐103a‐3p, and overexpression of FBXW7 significantly ameliorated LPS‐induced septic liver injury in mice. Finally, knockdown of FBXW7 markedly reversed anti‐miR‐103a‐3p‐mediated suppression of septic liver injury in mice. In conclusion, interfering miR‐103a‐3p or overexpression of FBXW7 improved LPS‐induced septic liver injury by suppressing apoptosis, inflammation, and oxidative reaction.