Complex Evaluation of Surfactant Protein A and D as Biomarkers for the Severity of COPD.

Purpose: Pulmonary surfactant proteins A (SP-A) and D (SP-D) are lectins, involved in host defense and regulation of pulmonary inflammatory response. However, studies on the assessment of COPD progress are limited. Patients and Methods: Pulmonary surfactant proteins were obtained from the COPD mouse model induced by cigarette and lipopolysaccharide, and the specimens of peripheral blood and bronchoalveolar lavage (BALF) in COPD populations. H&E staining and RT-PCR were performed to demonstrate the successfully established of the mouse model. The expression of SP-A and SP-D in mice was detected by Western Blot and immunohistochemistry, while the proteins in human samples were measured by ELISA. Pulmonary function test, inflammatory factors (CRP, WBC, NLR, PCT, EOS, PLT), dyspnea index score (mMRC and CAT), length of hospital stay, incidence of complications and ventilator use were collected to assess airway remodeling and progression of COPD. Results: COPD model mice with emphysema and airway wall thickening were more prone to have decreased SP-A, SP-D and increased TNF-α, TGF-ß, and NF-kb in lung tissue. In humans, SP-A and SP-D decreased in BALF, but increased in serum. The serum SP-A and SP-D were negatively correlated with FVC, FEV1, FEV1/FVC, and positively correlated with CRP, WBC, NLR, mMRC and CAT scores (P < 0.05, respectively). The lower the SP-A and SP-D in BALF, the worse the lung function and the increased probability of complications and ventilator use. Moreover, the same trend emerged in COPD patients grouped according to GOLD severity grade (Gold 1-2 group vs Gold 3-4 group). The worse the patient's condition, the more pronounced the change. Conclusion: This study suggests that SP-A and SP-D may be related to the progression and prognostic evaluation of COPD in terms of airway remodeling, inflammatory response and clinical symptoms, and emphasizes the necessity of future studies of surfactant protein markers in COPD.

The circular RNA TLK1 exacerbates myocardial ischemia/reperfusion injury via targeting miR-214/RIPK1 through TNF signaling pathway.

PURPOSE: Myocardial ischemia/reperfusion injury (IRI) induces cardiomyocytes death and leads to loss of cardiac function. Circular RNAs (circRNA) have gain increasing interests in modulating myocardial IRI. In this study, we aim to investigate the role and exact mechanism of circTLK1 in the pathogenesis of myocardial IRI. METHODS: Myocardial IRI was developed in mice with measuring hemodynamic parameters and the activity of serum myocardial enzymes to evaluate cardiac function. HE and TTC staining were performed to assess infarct area. Expression patterns of circTLK1 and miR-214 were investigated using qRT-PCR assay. Gene expression of circTLK1, miR-214 or RIPK was altered by transfecting with their overexpression or knockdown vectors. The apoptosis of cardimyocytes was assessed by TUNEL staining and Caspase-3 activity analysis. Apoptosis-related markers Bcl-2, Bax, and caspase3, as well as TNF-α signals were determined by western blotting. The interactions of circTLK1/miR-214 and miR-214/RIPK1 were verified using luciferase reporter assay. RNA immunoprecipitation (RIP) was subjected to further definite the direct binding of circTLK1/miR-214. The regulatory network of circTLK1/miR-214/RIPK1 was further validated in vivo. RESULTS: circTLK1 was an up-regulated circRNA found in a myocardial IRI mouse model. Mice with silencing circTLK1 significantly alleviated the impaired cardiac function indexes and decreased infarct area, thus attenuating the pathogenesis of myocardial IRI. Knockdown of circTLK1 dramatically decreased cardiomyocytes apoptosis, which was determined by apoptosis-related proteins. miR-214 was identified as a downstream effector to reverse circTLK1-mediated damage effects in myocardial IRI. miR-214 could directly target RIPK1 via binding to its' 3'-UTR. Overexpression of RIPK1 led to impaired cardiac function indexes, increased infarct area, and cell apoptosis, which abolished the protective effects of miR-214. The TNF signaling pathway was demonstrated to be involved in the circTLK1/miR-214/RIPK1 regulatory network in myocardial IRI. CONCLUSION: Taken together, our study revealed an up-regulated circRNA, circTLK1, could exacerbate myocardial IRI via targeting miR-214/RIPK1-mediated TNF signaling pathway, which may provide therapeutic targets for treatment.

MicroRNA-26b relieves inflammatory response and myocardial remodeling of mice with myocardial infarction by suppression of MAPK pathway through binding to PTGS2.

BACKGROUND: Myocardial infarction (MI) is a common cardiovascular disease caused by myocardial ischemia. Also, microRNA (miRNA) participates in the pathophysiology of many cardiovascular diseases, which can affect stem cell transplantation in the treatment of MI. In this study, our aim is to explore effect of miR-26b on inflammatory response and myocardial remodeling through the MAPK pathway by targeting PTGS2 in mice with MI. METHODS: Microarray data analysis was conducted to screen MI-related differentially expressed gens (DEGs). Relationship between miR-26b and PTGS2 was testified. Cardiac function, inflammatory reaction, infarct size, and myocardial fibrosis were observed. The miR-26b expression and mRNA and protein levels of, PTGS2, ERK, JNK and p38 and Bcl-2/Bax were examined. The effect of miR-26b on cell apoptosis was also analyzed. RESULTS: MiR-26b was predicted to target PTGS2 further to mediate the MAPK pathway, thus affecting MI. MiR-26b negatively targeted PTGS2. MI mice showed decreased cardiac function, as well as increased inflammatory reaction, myocardial injury, area of fibrosis and myocardial cell apoptosis. After injection of miR-26b agomir or NS-398 (PTGS2 inhibitor), inflammatory response of MI mice was attenuated and myocardial remodeling induced by MI was alleviated. CONCLUSION: These findings indicate that miR-26b inhibits PTGS2 to activate the MAPK pathway, so as to reduce inflammatory response and improve myocardial remodeling in mice with MI.

IRAK3 gene silencing prevents cardiac rupture and ventricular remodeling through negative regulation of the NF-κB signaling pathway in a mouse model of acute myocardial infarction.

Cardiac rupture and ventricular remodeling are recognized as the severe complications and major risk factors of acute myocardial infarction (AMI). This study aims to evaluate the regulatory roles of interleukin-1 receptor-associated kinase 3 (IRAK3) and nuclear factor-κB (NF-κB) signaling pathway in cardiac rupture and ventricular remodeling. Microarray analysis was performed to screen AMI-related differentially expressed genes and IRAK3 was identified. The models of AMI were established in male C57BL/6 mice to investigate the functional role of IRAK3. Afterwards, lentivirus recombinant plasmid si-IRAK3 was constructed for IRAK3 silencing. Next, cardiac function parameters were measured in response to IRAK3 silencing. The regulatory effects that IRAK3 had on myocardial infarct size and the content of myocardial interstitial collagen were analyzed. The regulation of IRAK3 silencing on the NF-κB signaling pathway was further assayed. The obtained results indicated that highly expressed IRAK3 and activated NF-κB signaling pathway were observed in myocardial tissues of mouse models of AMI, accompanied by increased expression of matrix metalloproteinase (MMP)-2/9 and tissue inhibitor of metalloproteinase 2 (TIMP-2). Notably, IRAK3 gene silencing inhibited the activation of NF-κB signaling pathway. Furthermore, IRAK3 gene silencing led to the decreased thickness of infarct area and collagen content of myocardial interstitium, alleviated diastolic, and systolic dysfunctions, as well as, facilitated cardiac functions in mice with AMI, corresponding to decreased expression of MMP-2/9 expression and increased expression of TIMP-2. Taken together, silencing of IRAK3 inactivates the NF-κB signaling pathway, and thereby impeding the cardiac rupture and ventricular remodeling, which eventually prevents AMI progression.