Rapid 1α,25(OH)₂D₃ membrane-mediated activation of Ca²⁺/calmodulin-dependent protein kinase II in growth plate chondrocytes requires Pdia3, PLAA and caveolae

Abstract

1α,25-Dihydroxy vitamin D3 [1α,25(OH)2D3] regulates growth zone chondrocytes (GC) via classical steroid hormone receptor-mediated gene transcription and by initiating rapid membrane-mediated signaling pathways. 1α,25(OH)2D3 initiates its membrane effects via its specific membrane-associated receptor (Pdia3) in caveolae. 1α,25(OH)2D3 binding to Pdia3 leads to phospholipase-A2 (PLA2)-activating protein (PLAA) activation, stimulating PLA2, resulting in prostaglandin E2 (PGE2) release and protein kinase C activation. Recently, we reported that 1α,25(OH)2D3 rapidly activates Ca(2+)/calmodulin-dependent protein kinase II (CaMKII) in GC cells. However, the roles of Pdia3, PLAA and caveolae in 1α,25(OH)2D3-dependent rapid activation of CaMKII are not clear. The aim of the present study was to evaluate the roles of Pdia3, PLAA and caveolae in 1α,25(OH)2D3 membrane-stimulated CaMKII activation. Pre-treating chondrocytes from the growth zone of the rat costochondral cartilage with antibodies against PLAA or Pdia3 blocked activation of CaMKII by 1α,25(OH)2D3. PLAA peptide rapidly activated CaMKII in GC cells. Caveolae disruption abolished CaMKII activation in response to 1α,25(OH)2D3 or PLAA peptide treatment. Immunoprecipitation studies showed increased CaM binding to PLAA in response to 1α,25(OH)2D3. The results indicated that Pdia3, PLAA and caveolae are required for rapid 1α,25(OH)2D3 membrane-mediated activation of CaMKII. 1α,25(OH)2D3 signaling via Pdia3 receptor triggered the interaction between PLAA and CaM suggesting that CaM may play a major role linking PLAA to CaMKII in membrane-mediated actions of 1α,25(OH)2D3.

ESWT Enhances Expression of Pdia-3 which is a Key Factor of 1α,25-Dihydroxyvitamin D3 Rapid Membrane Signaling Pathway in Treatment of Early Osteoarthritis Knee

“…Our current study provides the first evidence from immunohistochemistry that shockwave therapy can induce articular cartilages expression of Pdia-3, the critical transcription factor responsible for the matrix formation of chondrocyte. Recent studies reported that 1α,25(OH)2D3 rapidly stimulated membrane signaling via Pdia-3 dependent activation in growth zone chondrocytes and promotes the production of matrix protein [11,13,20,22,42,43]. The present study showed the decrease of cartilage matrix loss and increased aggrecan and collagen II expression in shockwave group.…”

“…It has been investigated action on osteoblasts and growth plate chondrocytes through classic unclear vitamin D receptor (VDR) and Pdia-3. Pdia-3 was demonstrated to a key factor in 1α,25(OH)2D3 induced phospholipase A2 (PLA2) and protein kinase C (PKC) activation and downstream responses of gene transcription [12,13].…”

Phospholipase A2-activating protein is associated with a novel form of leukoencephalopathy

“…Experimentally, activation of PLAA was recently shown to occur via 1a,25(OH) 2 D3 binding to a specific membrane-associated receptor, PDIA3, in caveolae, regulating growth zone chondrocytes (Doroudi et al, 2014). These findings might explain non-neurological features of progressive chest deformities (kyphosis/pectus carinatum) present in affected individuals.…”

Calcitriol, the Bioactive Metabolite of Vitamin D, Increases Ventricular K+ Currents in Isolated Mouse Cardiomyocytes

“…We are, however, inclined to favor a non-genomic action mediated by membrane VDR due to the short time required (15–30 min) and the fact that VDR has been reported to be expressed in the tubular system of ventricular myocytes (Tishkoff et al, 2008), a region where voltage-gated calcium and potassium channels are predominantly localized (Takeuchi et al, 2000; Brette and Orchard, 2003). On the other hand, protein disulfide isomerase family A member 3 (PDIA3) has been proposed as a membrane receptor for calcitriol that mediates some of its non-genomic effects in chondrocytes, osteoblasts and other cell types (Boyan et al, 2003; Doroudi et al, 2014a,b). Intriguingly, both PDIA3 and VDR are located in caveolae in many tissues and cell types, and an interaction between them has been observed, suggesting that VDR and PDIA3 might both be required for some non-genomic actions of calcitriol (Sequeira et al, 2012; Chen et al, 2013).…”