Application of Static Magnetic Field in Salivary Gland Cell to Regulate Calcium Ion Influx to Improve Salivation for Treating Xerostomia

Although the effects may be varied upon cell types, field intensity, and exposure time, the static magnetic fields (SMF) has been shown to modulate gene expression, intracellular components, growth, viability, morphology, metabolism, biomolecules synthesis, membranes and channel properties, and even enzymatic activity. SMF can re-arrange the phospholipid bilayer to improve the cell membrane rigidity. Consequently, the Ca2+ influx and other cellular functions will be influenced. Salivation is regulated by the sympathetic and parasympathetic autonomic nervous systems. Neurotransmitter-regulated salivation is achieved by a coordinated sequence of intracellular signaling events. The regulation of intracellular ionised calcium ([Ca2+]i) is critical to the modulation of salivary gland cell function. Therefore, we propose that SMF may be used to treat xerostomia. Removal of salivary tumors, radiation therapy to tumors, and Sjögren's syndrome can cause xerostomia. Hyposalivation may lead to dental caries, oral infections, difficulties with eating, talking, swallowing, and alter taste sensation that strongly affect quality of life. Ca2+-activated K+ (SK) channel, Na+-K+-2Cl- cotransporter (NKCC1), and aquaporin (AQP) are three of the major regulators of [Ca2+]i. In addition to surface channels, tight junction proteins (claudins, occludin, and zonula occludens (ZO-1)) are an essential structure to salivary glands. Gap junction protein conncexins (Cx) also allow cells to exchange cytoplasmic molecules and promote the release of secretory products. The junctional proteins were down-regulated in Sjögren's syndrome patients, which suggests that the cell coupling also regulate salivary fluid secretion. In this project, human salivary acinar cells will be cultured as salivary organoids. The influences of SMF on the surface channels, cell-coupling, calcium ion influx and salivation of salivary cells will be studied. The purpose of this project is demonstrate to the hypothesis of SMF may modulate cell coupling, [Ca2+]i and salivary fluid secretion by using the salivary organoid model. We expect these results can develop a buccal magnetic patch to improve xerostomia.