miR-26a-5p mediates TLR signaling pathway by targeting CTGF in LPS-induced alveolar macrophage

Expression analysis of mTOR-associated lncRNAs in multiple sclerosis

mTOR has been shown to be involved in the regulation of immune responses and differentiation of immune cells. This protein is a candidate molecule for unraveling the molecular mechanisms of autoimmune disorders such as multiple sclerosis (MS). We designed the current study to assess expression of MTOR, and four associated long non-coding RNAs (lncRNAs), namely SNHG1, SNHG3, SHNG5 and DANCR in the peripheral blood of patients with MS compared with healthy controls. Analysis of real-time PCR results has shown down-regulation of SNHG5 and DANCR in MS patients compared with controls. Sex of study participants had no significant effect on expression of either genes and the interaction of sex and disease on expression levels of all studied genes were insignificant. There was a significant negative correlation between expression levels of MTOR gene and disease duration. No other significant correlations were detected between genes expressions and clinical/demographic data. SNHG5 and DANCR transcript levels had AUC values of 0.88 and 0.68 in separation of patients with MS from healthy controls, respectively. Taken together, our study suggests participation of two mTOR-related lncRNAs, i.e. SNHG5 and DANCR in the pathophysiology of MS.

Interaction between non-coding RNAs and Toll-like receptors

Toll-like receptors (TLRs) are a large group of pattern recognition receptors which are involved in the regulation of innate immune responses. Based on the interplay between TLRs and adapter molecules, two distinctive signaling cascades, namely the MyD88-dependent and TRIF-dependent pathways have been recognized. TLRs are involved in the development of a wide variety of diseases including cancer and autoimmune disorders. A large body of evidence has shown interaction between two classes of non-coding RNAs, namely microRNAs (miRNAs) and long noncoding RNAs (lncRNAs). These interactions have prominent roles in the pathogenesis of several disorders including infectious disorders, autoimmune conditions and neoplastic disorders. This review aims at description of the interaction between these non-coding RNAs and TLRs.

A Comprehensive miRNome Analysis of Macrophages Isolated from db/db Mice and Selected miRNAs Involved in Metabolic Syndrome-Associated Cardiac Remodeling

Cardiac macrophages are known from various activities, therefore we presume that microRNAs (miRNAs) produced or released by macrophages in cardiac tissue have impact on myocardial remodeling in individuals with metabolic syndrome (MetS). We aim to assess the cardiac macrophage miRNA profile by selecting those miRNA molecules that potentially exhibit regulatory functions in MetS-related cardiac remodeling. Cardiac tissue macrophages from control and db/db mice (an animal model of MetS) were counted and sorted with flow cytometry, which yielded two populations: CD45+CD11b+CD64+Ly6Chi and CD45+CD11b+CD64+Ly6Clow. Total RNA was then isolated, and miRNA expression profiles were evaluated with Next Generation Sequencing. We successfully sequenced 1400 miRNAs in both macrophage populations: CD45+CD11b+CD64+Ly6Chi and CD45+CD11b+CD64+Ly6Clow. Among the 1400 miRNAs, about 150 showed different expression levels in control and db/db mice and between these two subpopulations. At least 15 miRNAs are possibly associated with MetS pathology in cardiac tissue due to direct or indirect regulation of the expression of miRNAs for proteins involved in angiogenesis, fibrosis, or inflammation. In this paper, for the first time we describe the miRNA transcription profile in two distinct macrophage populations in MetS-affected cardiac tissue. Although the results are preliminary, the presented data provide a foundation for further studies on intercellular cross-talk/molecular mechanism(s) involved in the regulation of MetS-related cardiac remodeling.

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.