Title: miR-140-3p regulation of TNF-α-induced CD38 expression in human airway smooth muscle cells.
Authors: Jude, Joseph A; Dileepan, Mythili; Subramanian, Subbaya; Solway, Julian; Panettieri Jr, Reynold A; Walseth, Timothy F; Kannan, Mathur S
Published In Am J Physiol Lung Cell Mol Physiol, (2012 Sep)
Abstract: CD38, a membrane protein expressed in airway smooth muscle (ASM) cells, plays a role in cellular Ca(2+) dynamics and ASM contractility. In human ASM (HASM) cells, TNF-α induces CD38 expression through activation of MAPKs, NF-κB, and AP-1, and its expression is differentially elevated in cells from asthmatic patients compared with cells from nonasthmatic subjects. The CD38 3'-untranslated region (UTR) has targets for miR-140-3p. We hypothesized that miR-140-3p regulates CD38 expression in HASM cells by altering CD38 mRNA stability. Basal and TNF-α-induced expression of miR-140-3p was determined in nonasthmatic ASM (NAASM) and asthmatic ASM (AASM) cells. NAASM and AASM cells were transfected with control, miR-140-3p mimic, or miR-140-3p antagomirs, and CD38 expression and CD38 mRNA stability were determined. Luciferase reporter assays were used to determine miR-140-3p binding to the CD38 3'-UTR. Activation of p38, ERK, and JNK MAPKs, NF-κB, and AP-1 was determined in miR-140-3p mimic-transfected NAASM. TNF-α attenuated miR-140-3p expression in NAASM and AASM cells, but at a greater magnitude in AASM cells. CD38 mRNA expression was attenuated by miR-140-3p mimic at comparable magnitude in NAASM and AASM cells. Mutated miR-140-3p target on the CD38 3'-UTR reversed the inhibition of luciferase activity by miR-140-3p mimic. CD38 mRNA stability was unaltered by miR-140-3p mimic in NAASM or AASM cells following arrest of transcription. TNF-α-induced activation of p38 MAPK and NF-κB was attenuated by miR-140-3p mimic. The findings indicate that miR-140-3p modulates CD38 expression in HASM cells through direct binding to the CD38 3'-UTR and indirect mechanisms involving activation of p38 MAPK and NF-κB. Furthermore, indirect mechanisms appear to play a major role in the regulation of CD38 expression.
PubMed ID: 22773691
MeSH Terms: 3' Untranslated Regions/genetics; ADP-ribosyl Cyclase 1/genetics; ADP-ribosyl Cyclase 1/metabolism*; Asthma/metabolism; Asthma/pathology; Cells, Cultured; Down-Regulation; Gene Expression; Humans; MAP Kinase Signaling System; Membrane Glycoproteins/genetics; Membrane Glycoproteins/metabolism*; MicroRNAs/genetics; MicroRNAs/metabolism*; Myocytes, Smooth Muscle/metabolism*; NF-kappa B/metabolism; RNA Interference*; Respiratory System/metabolism; Respiratory System/pathology*; Tumor Necrosis Factor-alpha/physiology*; p38 Mitogen-Activated Protein Kinases/metabolism