MiR-543 Regulates the Development of Chronic Obstructive Pulmonary Disease by Targeting Interleukin-33.

BACKGROUND: This main aim of the study was to evaluate the expression and specific role of miR-543 in the progression of chronic obstructive pulmonary disease (COPD), thereby evaluating their diagnostic ability and treatment in COPD patients. METHODS: Real time PCR was carried out to explore the level of miR-543 in the plasma and lung tissues of COPD patients and controls. ELISA was performed to analyze the level of interleukin-33 (IL-33). Dual luciferase was used to validate the target gene of miR-543. RESULTS: First, we showed that the level of miR-543 was increased in the plasma and lung tissues of COPD patients than those of healthy control. Receiver operating characteristic (ROC) analysis indicated that plasma miR-543 could differentiate COPD patients from healthy controls. More importantly, we found that plasma miR-543 was gradually decreased in COPD patients according to FEV1 ≤ 80% (mild), 50% ≤ FEV1 < 80% (moderate), 30% ≤ FEV1 < 50% (moderate), FEV1 < 30% (very severe). Meanwhile, miR-543 was also decreased in COPD patients according to 6MWD ≥ 350 m (mild), 250 m ≤ 6MWD < 349 m (moderate), 150 m ≤ 6MWD < 249 m (severe), and 6MWD ≤ 149 m (very severe). Dual luciferase reporter assay showed that IL-33 was a target gene of miR-543. CONCLUSIONS: In summary, we showed novel data that decreased plasma miR-543 may enhance the progression of COPD via targeting IL-33. Furthermore, plasma miR-543 could be used as a potential non-invasive biomarker for COPD patients, which may shed light on the diagnosis and therapy of COPD.

Nicotine depresses facial stimulation-evoked molecular layer interneuron-Purkinje cell synaptic transmission via α7 nicotinic acetylcholine receptors in mouse cerebellar cortex.

Nicotine modulates cerebellar physiology function by interacting with nicotinic acetylcholine receptors (nAChRs) and is involved in modulation of cerebellar cortical circuitry functions. Here, we investigated the effect of nicotine on sensory stimulation-evoked molecular layer interneuron-Purkinje cell (MLI-PC) synaptic transmission mouse cerebellar cortex using in vivo cell-attached recording technique and pharmacological methods. The results show that micro-application of nicotine to the cerebellar molecular layer significantly decreased sensory stimulation-evoked MLI-PC synaptic transmission in mouse cerebellar cortex. Nicotine-induced depression in sensory stimulation-evoked MLI-PC synaptic transmission was abolished by either a non-selective nAChR blocker, hexamethonium, or the α7-nAChR antagonist methyllycaconitine (MLA), but not the selective α4ß2-nAChR antagonist dihydro-ß-erythroidine. Notably, molecular layer micro-application of nicotine did not significantly affect the number of spontaneous or facial stimulation-evoked action potentials of MLIs. Moreover, nicotine produced significant increases in the amplitude and frequency of miniature inhibitory postsynaptic currents of PCs, which were abolished by MLA in cerebellar slices. These results indicate that micro-application of nicotine to the cerebellar molecular layer depresses facial stimulation-induced MLI-PC synaptic transmission by activating α7 nAChRs, suggesting that cholinergic inputs modulate MLI-PC synapses to process sensory information in the cerebellar cortex of mice in vivo.

The effect of core fucosylation-mediated regulation of multiple signaling pathways on lung pericyte activation and fibrosis.

The main event in the progression of pulmonary fibrosis is the appearance of myofibroblasts. Recent evidence supports pericytes as a major source of myofibroblasts. TGFß/Smad2/3 and PDGF/Erk signaling pathways are important for regulating pericyte activation. Previous studies have demonstrated that PDGFßR and TGFßR are modified by core fucosylation (CF) catalyzed by α-1,6-fucosyltransferase (FUT8). The aim of this study was to compare the effect of inhibiting CF versus the PDGFßR and TGFßR signaling pathways on pericyte activation and lung fibrosis. FUT8shRNA was used to knock down FUT8-mediated CF both in vivo and in isolated lung pericytes. The small molecule receptor antagonists, ST1571 (imatinib) and LY2109761, were used to block the PDGFß/pErk and TGFß/pSmad2/3 signaling pathways, respectively. Pericyte detachment and myofibroblastic transformation were assessed by immunofluorescence and Western blot. Histochemical and immunohistochemical staining were used to evaluate the effect of the intervention on pulmonary fibrosis. Our findings demonstrate that FUT8shRNA significantly blocked pericyte activation and the progression of pulmonary fibrosis, achieving intervention effects superior to the small molecule inhibitors. The PDGFß and TGFß pathways were simultaneously affected by the CF blockade. FUT8 expression was upregulated with the transformation of pericytes into myofibroblasts, and silencing FUT8 expression inhibited this transformation. In addition, there is a causal relationship between CF modification catalyzed by FUT8 and pulmonary fibrosis. Our findings suggest that FUT8 may be a novel therapeutic target for pulmonary fibrosis.

Suppression of SMOC2 reduces bleomycin (BLM)-induced pulmonary fibrosis by inhibition of TGF-ß1/SMADs pathway.

Although the initiation and modulation of lung fibrosis has been widely investigated, the pathogenesis was not well understood. Secreted modular calcium-binding protein 2 (SMOC2) as the secreted protein acidic is enriched in cysteine (SPARC) family of matricellular proteins, which are important in regulating cell-matrix interactions. Here we aimed to calculate the effects and molecular mechanism of SMOC2 on the progression and severity of lung fibrosis in murine bleomycin (BLM)-induced mice. The pulmonary fibrosis was significantly induced by BLM in wild type (WT) C57BL6 mice, as evidenced by the lung sections histology and collagen accumulation using H&E and Masson Trichrome staining. Notably, SMOC2 knockout (SMOC2-/-) mice treated with BLM exhibited the decrease in inflammation accompanied by the reduction of neutrophils, macrophages and lymphocytes in bronchoalveolar lavage fluids (BALF). In addition, the levels of inflammation-associated cytokines and chemokines induced by BLM were also decreased in BALF obtained from SMOC2-/- mice. Meanwhile, SMOC2-/- suppressed the progression of pulmonary fibrosis, as evidenced by the reduction in levels of transforming growth factor-ß1 (TGF-ß1), α-smooth muscle actin (α-SMA), p-SMAD2 and p-SMAD3 in lung tissue samples. Increasing expression of SMOC2 in TGF-ß1 treated cells were further observed in vitro. Of note, up regulation of SMOC2 activated-fibrosis development in MRC-5 cells, along with increase of α-SMA, p-SMAD2 and p-SMAD3 were determined. In contrast, SMOC2 knockdown reduced TGF-ß1-stimulated expressions of α-SMA, p-SMAD2 and p-SMAD3 in cells. The findings above suggested that SMOC2 knockout contributes to inhibit BLM-induced pulmonary fibrosis.

Acrolein-induced autophagy-dependent apoptosis via activation of the lysosomal-mitochondrial pathway in EAhy926 cells.

Acrolein, a highly reactive α,ß-unsaturated aldehyde, is a toxic component of cigarette smoke. As a lipid peroxidation biomarker, acrolein plays an important role in a wide variety of disease states, such as neurodegenerative, Alzheimer's disease, diabetes and atherosclerosis. Endothelial cell injury is one of the initiating factors of atherosclerosis, but the underlying molecular mechanisms remain unclear. Our study primarily focused on acrolein-induced autophagy-dependent apoptosis and the possible molecular mechanism. The results showed that treatment with acrolein increased the number of intracellular GFP-LC3 II punctuates and the expression of autophagosome biomarker LC3-II, with the low dose (25 µM) or at the early stage of treatment (3 h). Following treatment of EAhy926 cells with acrolein for 6 h, lysosomal permeabilization changed, and cathepsin B (CB) was released. Additionally, acrolein induced the collapse of mitochondrial transmembrane potential, and cytochrome c was released. Furthermore, caspase-3 and caspase-9 activation showed that acrolein induced EAhy926 cell apoptosis. Autophagy inhibitor 3MA and CB inhibitor CA-074 Me (CA) attenuated acrolein-induced apoptosis. Collectively, our results suggested that acrolein-induced apoptosis is autophagy-dependent, occurring via injury to lysosomes and mitochondria. This study provides new mechanistic insight toward understanding the pathogenesis of acrolein-related disorders.