Diagnostic values of soluble triggering receptor expressed on myeloid cells (sTREM-1) and interferon-inducible protein-10 (IP-10) for severe mycoplasma pneumoniae pneumonia in children.

OBJECTIVE: Early diagnosis of Severity Mycoplasma Pneumoniae Pneumonia (SMPP) has been a worldwide concern in clinical practice. Two cytokines, soluble Triggering Receptor Expressed on Myeloid cells (sTREM-1) and Interferon-Inducible Protein-10 (IP-10), were proved to be implicated in bacterial infection diseases. However, the diagnostic value of sTREM-1 and IP-10 in MPP was poorly known. This study aimed to investigate the diagnostic value of sTREM-1 and IP-10 for SMPP. METHODS: In this prospective study, the authors enrolled 44 children with MPP, along with their clinical information. Blood samples were collected, and cytokine levels of sTREM-1 and IP-10 were detected with ELISA assay. RESULTS: Serum levels of sTREM-1 and IP-10 were positively correlated with the severity of MPP. In addition, sTREM-1 and IP-10 have significant potential in the diagnosis of SMPP with an Area Under Curve (AUC) of 0.8564 (p-value = 0.0001, 95% CI 0.7461 to 0.9668) and 0.8086 (p-value = 0.0002, 95% CI 0.6918 to 0.9254) respectively. Notably, the combined diagnostic value of sTREM-1 and IP-10 is up to 0.911 in children with SMPP (p-value < 0.001, 95% CI 0.830 to 0.993). CONCLUSIONS: Serum cytokine levels of sTREM-1 and IP-10 have a great potential diagnostic value in children with SMPP.

p14ARF ameliorates inflammation and airway remodeling in nitric acid aerosol inhalation-induced bronchiolitis obliterans.

BACKGROUND: To investigate the protective effect of p14ARF in a nitric acid (NA) aerosol inhalation-induced bronchiolitis obliterans (BO) mouse model and its potential regulatory mechanism. METHODS: A BO mouse model was established by NA aerosol inhalation. The expressions of p14ARF, phosphatidylinositol-3-kinase (PI3K), and protein kinase B (AKT) were detected by quantitative reverse transcription PCR (qRT-PCR) and western blot (WB). Hematoxylin (HE) staining, Masson staining, and periodic acid-Schiff (PAS) staining observed pulmonary histological changes. TdT-mediated dUTP nick end labeling (TUNEL) staining detected pulmonary cell apoptosis, and enzyme-linked immunosorbent assay (ELISA) measured matrix metalloproteinase-2 (MMP-2), MMP-9, tissue inhibitor of metalloproteinase-1 (TIMP-1), interleukon-6 (IL-6), and transforminh growth factor-ß (TGF-ß) levels in lung tissue and bronchoalveolar lavage fluid (BALF). RESULTS: The expressions of p14ARF, PI3K, and AKT showed a time gradient change, with a decrease trend (*P < 0.05 and **P < 0.01). Severe inflammatory infiltration and tracheal fibrosis were found in lung tissue in the modeling group (BO group) compared with the control group (Con group). The pH, PaO2, and PaO2/FiO2 values significantly reduced, while the PaCO2 value and the number of TUNEL-positive cells increased in BO group (P < 0.05). In addition, MMP-2, MMP-9, IL-6, and TGF-ß levels remarkably increased, with an increase in the number of white blood cells, neutrophils, and lymphocytes in BO group (P < 0.05). Furthermore, p14ARF up-regulation reversed the trend of the aforementioned indexes in BO mice. CONCLUSIONS: p14ARF ameliorated the inflammatory response and airway remodeling in a BO mouse model via the PI3K/AKT pathway.

Sphingosine Kinase-1 (SPHK1) promotes inflammation in infantile pneumonia by regulating NLRP3 inflammasome and SIRT1 expression.

BACKGROUND: Infantile pneumonia is an acute inflammatory disorder of the lung caused by mycoplasma pneumonia. SPHK1 (sphingosine kinase-1) signaling pathway is involved in the process of inflammatory diseases. However, whether SphK1 regulates inflammatory responses in infantile pneumonia remains unclear. In this study, we investigated the role of SPHK1 in infantile pneumonia and its underlying mechanisms. METHODS: Serum samples of 12 patients with infantile pneumonia and healthy controls were obtained from Hunan Children's Hospital. To induce pneumonia, mice were administrated with LPS (lipopolysaccharide) into the lung. RAW264.7 cells were used as an in vitro macrophage model stimulated with LPS or PBS for 4 h. RESULTS: SPHK1 mRNA level and protein level in the LPS-treated mice and patients with infantile pneumonia were significantly increased. SPHK1 promoted inflammation and lung injury in mice with infantile pneumonia. The knockdown of SPHK1 expression inhibited inflammation and restrained lung injury in mice with infantile pneumonia. SPHK1 overexpression also exacerbated inflammation in RAW264.7 cells stimulated by LPS, and SPHK1 silencing reduced inflammatory responses. We further showed that SPHK1 induced NLRP3 (NLR Family Pyrin Domain Containing 3) activity by inhibiting SIRT1 expression. CONCLUSION: Our study demonstrated that SPHK1 promotes inflammation of infantile pneumonia by modulating NLRP3 inflammasome via the regulation of SIRT1 expression and mitochondrial permeability transition.

Twist2 Reduced NLRP3-Induced Inflammation of Infantile Pneumonia via Regulation of Mitochondrial Permeability Transition by FOXO1.

BACKGROUND: Infantile pneumonia is an acute inflammatory lesion of the lung caused by mycoplasma pneumonia. Indeed, Twist2 signaling pathway controls inflammatory reaction, oxidative stress, and other biological reaction. However, the regulation of Twist2 on the inflammation in infantile pneumonia remains unclear. This study explained that the function and mechanism of Twist2 in infantile pneumonia. METHODS: The subjects included the serum samples of 12 patients with infantile pneumonia and normal healthy volunteers from Hunan Children's Hospital. Besides, mice were given with lipopolysaccharide (LPS) into the lung. Moreover, RAW264.7 macrophages were stimulated with LPS for 4 h and added to the culture medium. RESULTS: In present study, in serum of patients with infantile pneumonia or lung tissue of mice model with infantile pneumonia, TWIST2 expression was lessened. Apart from that, TWIST2 protein could reduce the inflammatory reaction in mice model with infantile pneumonia, resulting in an inhibition in lung injury. Conversely, over-expression of TWIST2 also decreased inflammatory reaction in macrophages model via the regulation of FOXO1/NLRP3 pathway. Downregulation of TWIST2 promoted the inflammation in macrophages model by the regulation of FOXO1/NLRP3 pathway. CONCLUSION: According to the findings, present study have identified that the TWIST2 could reduce the inflammation of infantile pneumonia by NLRP3 inflammasome through the regulation of mitochondrial permeability transition and the induction of FOXO1 expression.

MiR-140 suppresses airway inflammation and inhibits bronchial epithelial cell apoptosis in asthma by targeting GSK3ß.

AIM OF THE STUDY: Asthma is a common and complex chronic inflammatory disease induced by genetic and environmental factors that affects the airways of the lungs. MicroRNAs (miRNAs) are key regulators of various cellular processes and have been shown to be critically involved in asthma progression. The objective of our study was to clarify the function and molecular mechanism of miR-140 in the progression of asthma. MATERIALS AND METHODS: MiR-140 expression was evaluated using RT-qPCR. Pathological changes in the lung tissue were confirmed using HE and PAS staining. The levels of IL-5, TGF-ß1, and IL-13 in the serum or bronchioalveolar lavage fluid were detected with an ELISA. Cellular apoptosis was measured using a TUNEL assay. The levels of Bax, Bcl-2, Cleaved caspase-3, and glycogen synthase kinase-3ß (GSK-3ß) were verified with a western blot. GSK3ß expression was also confirmed by immunohistochemistry. The binding ability between miR-140 and GSK3ß was confirmed using a luciferase reporter assay, RNA immunoprecipitation (RIP) assay and Pull-down assay. RESULTS: MiR-140 was markedly downregulated in asthmatic mice. Additionally, miR-140 weakened airway inflammation and bronchial epithelial cell apoptosis in asthmatic mice. Further experiments revealed that miR-140 negatively regulated GSK3ß expression and could bind to GSK3ß in asthma. Finally, rescue assays demonstrated that GSK3ß overexpression rescued the effects of miR-140 on asthma progression. CONCLUSION: MiR-140 targeted GSK3ß to suppress airway inflammation and inhibit bronchial epithelial cell apoptosis in asthma.

LncRNA NEAT1 regulates MMP-16 by targeting miR-200a/b to aggravate inflammation in asthma.

Asthma is a common respiratory disease which is characterized by persistent airway inflammation. Abnormal expression of long non-coding RNAs (lncRNAs) is observed in asthma. However, whether lncRNA nuclear-enriched abundant transcript 1 (NEAT1) regulates asthmatic inflammation and its mechanism still needs to be further investigated. The expression levels of inflammatory factors (tumour necrosis factor (TNF)-α, interleukin (IL)-4, IL-13, and IL-10) were detected using reverse transcription quantitative real-time PCR (RT-qPCR) and enzyme-linked immunosorbent assay (ELISA). MTT and flow cytometry assays were employed to determine cell proliferation and apoptosis, respectively. Dual luciferase reporter assay was performed to verify the relationship between miR-200a/b and MMP-16 or NEAT1. NEAT1 silencing markedly reduced TNF-α, IL-4, and IL-13 levels, while elevated IL-10 expression, suppressed cell proliferation, and promoted cell apoptosis. However, NEAT1 overexpression elicited the opposite effects on cell proliferation and inflammation cytokines secretion. What is more, NEAT1 negatively regulated miR-200a/b expression, and MMP16 was a target gene of miR-200a/b. miR-200a/b overexpression suppressed inflammation, cell proliferation, and enhanced cell apoptosis through regulation of MMP16. Moreover, MMP-16 overexpression or miR-200a/b inhibition abolished the regulatory effect of sh-NEAT1 on cell inflammation and apoptosis in BEAS-2B cells. NEAT1 acted as the role of sponge for miR-200a/b to regulate MMP-16 expression, thereby promoting asthma progression, suggesting that NEAT1 might have great potential as therapeutic target for asthma.

Elevation of miR-21, through targeting MKK3, may be involved in ischemia pretreatment protection from ischemia-reperfusion induced kidney injury.

BACKGROUND: Ischemia-reperfusion (IR) causes acute kidney injury (AKI), and ischemia pretreatment may exert protection. Mitogen-activated protein kinase kinase 3 (MKK3), which is involved in the signal transduction pathway in IR-induced injury, is a potential target of miR-21. We aimed to verify the targeting regulation of miR-21 on MKK3 and to explore the effects of miR-21-mediated MKK3 expression changes in AKI. METHODS: Vectors containing the MKK3 3'UTR and mutated MKK3-3U-M were constructed and co-transfected with nonsense miR, miR-21-5p mimics or inhibitor in HEK293 cells. Gene expressions were detected by dual luciferase reporter assay. The effects of miR-21 on mRNA and protein of MKK3 were investigated in HK-2 cells. Male C57BL/6J mice were treated with ischemic preconditioning (IPC) and IR. Kidney functions were assessed through monitoring serum creatinine (Scr) and blood urea nitrogen (BUN). Pathological changes were observed and scored with histological samples of kidney. Expression levels of miR-21, MKK3, interleukin (IL)-6, tumor necrosis factor (TNF)-α before and after IPC and IR were examined by real-time polymerase chain reaction and/or immunohistochemistry. RESULTS: miR-21 regulated the expression of MKK3 via 3'UTR. Following IR, MKK3, IL-6 and TNF-α levels were increased. Scr, BUN and pathological injuries were aggravated, and miR-21 expression was increased. IPC increased miR-21 levels ahead of IR and inhibited the increases in MKK3, IL-6 and TNF-α levels and the aggravation of Scr, BUN and pathological injuries. CONCLUSIONS: miR-21 targets MKK3 in vivo and in vitro, inhibiting the downstream factors IL-6 and TNF-α. Therefore, miR-21 might be involved in protection of IPC against IR of the kidney.