Reduction of TRPC1/TRPC3 mediated Ca2+-signaling protects oxidative stress-induced COPD

• Published in: Cellular signalling Vol. 107; p. 110681
• Main Authors: Shin, Samuel, Gombedza, Farai C., Awuah Boadi, Eugenia, Yiu, Allen J., Roy, Sanjit K., Bandyopadhyay, Bidhan C.
• Format: Journal Article
• Language: English
• Published: Elsevier Inc 01.07.2023
• Subjects: Ca2+ signaling; Lung disease; Oxidative stress; Pulmonary epithelial cells; TRPC channel; Oxidative stress; IP3R; CCh; Fura-2-AM; TRPC channel; 2-APB; LDH; Tg; TRPC; FBS; BCNU; SOCE; Lung disease; Ca2+ signaling; [Ca2+]i; DAPI; DAG; STIM 1; TGFβ1; OAG; PE; Pulmonary epithelial cells; NOX; ROS; GPCR; ROCE; PIP2; COPD; ERK
• ISSN: 0898-6568; 1873-3913; 1873-3913
• DOI: 10.1016/j.cellsig.2023.110681

Oxidative stress is a predisposing factor in Chronic Obstructive Pulmonary Disease (COPD). Specifically, pulmonary epithelial (PE) cells reduce antioxidant capacity during COPD because of the continuous production of reactive oxygen species (ROS). However, the molecular pathogenesis that governs such ROS activity is unclear. Here we show that the dysregulation of intracellular calcium concentration ([Ca2+]i) in PE cells from COPD patients, compared to the healthy PE cells, is associated with the robust functional expressions of Transient Receptor Potential Canonical (TRPC)1 and TRPC3 channels, and Ca2+ entry (SOCE) components, Stromal Interaction Molecule 1 (STIM1) and ORAI1 channels. Additionally, the elevated expression levels of fibrotic, inflammatory, oxidative, and apoptotic markers in cells from COPD patients suggest detrimental pathway activation, thereby reducing the ability of lung remodeling. To further delineate the mechanism, we used human lung epithelial cell line, A549, since the behavior of SOCE and the expression patterns of TRPC1/C3, STIM1, and ORAI1 were much like PE cells. Notably, the knockdown of TRPC1/C3 in A549 cells substantially reduced the SOCE-induced [Ca2+]i rise, and reversed the ROS-mediated oxidative, fibrotic, inflammatory, and apoptotic responses, thus confirming the role of TRPC1/C3 in SOCE driven COPD-like condition. Higher TRPC1/C3, STIM1, and ORAI1 expressions, along with a greater Ca2+ entry, via SOCE in ROS-induced A549 cells, led to the rise in oxidative, fibrotic, inflammatory, and apoptotic gene expression, specifically through the extracellular signal-regulated kinase (ERK) pathway. Abatement of TRPC1 and/or TRPC3 reduced the mobilization of [Ca2+]i and reversed apoptotic gene expression and ERK activation, signifying the involvement of TRPC1/C3. Together these data suggest that TRPC1/C3 and SOCE facilitate the COPD condition through ROS-mediated cell death, thus implicating their likely roles as potential therapeutic targets for COPD. Alterations in Ca2+ signaling modalities in normal pulmonary epithelial cells exhibit COPD through oxidative stress and cellular injury, compromising repair, which was alleviated through inhibition of store-operated calcium entry. Calcium, ROS, Cellular signaling, lung disease. Schematic representation of the proposed mechanism in developing chronic obstructive pulmonary disease (COPD) condition in pulmonary epithelial (PE) cells causing injury in PE cell involving intracellular calcium ([Ca2+]i) mobilization. A. Ca2+ entry in normal PE cells is activated through the GPCR-PLC pathway which yields diacylglycerol (DAG) to activate receptor-operated Ca2+ entry (ROCE), or IP3 to cause store-operated Ca2+ entry (SOCE). SOCE involves Transient Receptor Potential Canonical 1 (TRPC1) and TRPC3, through IP3 receptor (IP3R) and by the activation of ORAI1 channels by STIM1. B. In COPD PE cells a greater and prolonged rise in [Ca2+]i, due to SOCE activation caused by the robust functional expressions of TRPC1, TRPC3, and the SOCE components, STIM1 and ORAI1. Antioxidant capacity in COPD PE cells is substantially reduced due to continuous production of reactive oxygen species (ROS) with the robust expressions of fibrotic, inflammatory, oxidative stress, and apoptotic markers. Functional interaction of TRPC1/C3 with STIM1-Orai1 towards operating SOCE could potentially provide a novel mechanism for the development of COPD condition by compromising the repair and remodeling process. GPCR: G-protein coupled receptor; Gα: G-protein; PLC: Phospholipase C; IP3: Inositol trisphosphate; SERCA: sarco/endoplasmic reticulum Ca2+-ATPase; NOX4: Nicotinamide-adenine dinucleotide phosphate oxidases 4; transforming growth factor beta 1: TGF-β1; Fibronectin: FN1; IL-6: interleukin-6; MCP1: monocyte chemoattractant protein 1; BAX1: BCL2-associated X protein 1; BCL2: B-cell lymphoma 2. [Display omitted] •TRPC1/3 mediates store operated Ca2+ entry (SOCE) in COPD pulmonary epithelial (PE) cells.•COPD evokes oxidative stress induced detrimental pathway activation in PE cells.•Induction of oxidative stress in A549 cells resulting SOCE-induced COPD-like conditions.•TRPC1/3 ablation lowered Ca2+ entry and reversed apoptotic expression and p-ERK activation.