Brain-Derived Neurotrophic Factor Inhibits the Wound-Healing and Cell Proliferative Ability of Human Airway Epithelial Cells in Asthmatic Children

Long noncoding RNA ANRIL up-regulates CCND1 via sponging miR-98-5p to promote TGF-β1-induced human airway smooth muscle cell proliferation, migration, and extracellular matrix deposition

Excessive proliferation and migration of airway smooth muscle cell (ASMC) contribute to asthma pathogenesis. Long noncoding RNAs (lncRNAs) are reported to take part in asthma pathogenesis. This study is targeted at deciphering the role of the lncRNA antisense noncoding RNA in the INK4 locus (ANRIL) in ASMC proliferation, migration and extracellular matrix (ECM) deposition. qRT-PCR was performed to determine ANRIL, miR-98-5p, and cyclin D1 (CCND1) mRNA expression levels in transforming growth factor-β1 (TGF-β1)-treated ASMCs. CCK-8 and Transwell assays were employed to examine ASMC proliferation and migration, respectively. Dual-luciferase reporter gene assay and RNA immunoprecipitation assay were carried out for analyzing the targeted relationship of miR-98-5p with ANRIL or CCND1 mRNA 3'-UTR. The levels of CCND1 and ECM proteins (such as fibronectin, COL3A1, and COL1A2) in ASMCs were detected through Western blot. In this work, we found that ANRIL and CCND1 were up-regulated in TGF-β1-treated ASMCs, whereas miR-98-5p was down-regulated. ANRIL overexpression facilitated the proliferation, ECM deposition and migration of TGF-β1-induced ASMCs, while knocking down ANRIL had the opposite effect. Furthermore, ANRIL targeted miR-98-5p directly, and CCND1 was miR-98-5p's downstream target. ANRIL indirectly increased CCND1 expression in ASMCs via competitively binding to miR-98-5p. MiR-98-5p inhibition or CCND1 overexpression counteracted the inhibiting effect that ANRIL knockdown had on TGF-β1-stimulated ASMC proliferation, migration and ECM deposition. In conclusion, ANRIL indirectly up-regulates CCND1 expression by targeting miR-98-5p to promote ASMC proliferation, migration and ECM deposition, thus facilitating the pathogenesis of asthma.

The melatonergic pathway and its interactions in modulating respiratory system disorders

Melatonin is a key intracellular neuroimmune-endocrine regulator and coordinator of multiple complex and interrelated biological processes. The main functions of melatonin include the regulation of neuroendocrine and antioxidant system activity, blood pressure, rhythms of the sleep-wake cycle, the retardation of ageing processes, as well as reseting and optimizing mitochondria and thereby the cells of the immune system. Melatonin and its agonists have therefore been mooted as a treatment option across a wide array of medical disorders. This article reviews the role of melatonin in the regulation of respiratory system functions under normal and pathological conditions. Melatonin can normalize the structural and functional organization of damaged lung tissues, by a number of mechanisms, including the regulation of signaling molecules, oxidant status, lipid raft function, optimized mitochondrial function and reseting of the immune response over the circadian rhythm. Consequently, melatonin has potential clinical utility for bronchial asthma, chronic obstructive pulmonary disease, lung cancer, lung vascular diseases, as well as pulmonary and viral infections. The integration of melatonin's effects with the alpha 7 nicotinic receptor and the aryl hydrocarbon receptor in the regulation of mitochondrial function are proposed as a wider framework for understanding the role of melatonin across a wide array of diverse pulmonary disorders.