Ti₃C₂ Two-dimensional Nanomaterials-based Strategy For The Light-controlled Intracellular Calcium Signaling

Ca²⁺is an essential ion in various physiological activities of the body.It can maintain the potential on both sides of the cell membrane in normal nerve conduction function,muscle contraction and relaxation function,and neuromuscular conduction function.Besides,the mechanism of physiological action of some hormones is mediated by calcium ions in target cells.Ca²⁺is a ubiquitous second messenger that controls various cellular functions,and the imbalances of Ca2+with high concentration may cause cell death.The homeostasis of intracellular Ca²⁺are maintained by many Calcium channel proteins,of which temperature-sensitive TRPV1channel protein is of interesting.TRPV1 channel protein is a kind of non-selective cationic channel protein,which rapidly respond to environmental temperature and adjust the Ca²⁺permeability of nerve cells,mediating the temperature sensation.We envisioned that intracellular Ca²⁺could be precisely regulated via the temperature-responsive TRPV1 channel protein.Thus,this thesis proposed a novel strategy to achieve NIR light-controlled cellular calcium signaling via the photothermal effect of a newly developed two-dimensional?2D?nanomaterials Ti3C2.Objective:This thesis aims to optimize the cell membrane-modification on Ti3C22D nanomaterial for increased the affinity to target neural cells and the photothermal effect mediated temperature sensitivity to open or close the TRPV1 channel in nerve cells,enabling the precise control over intracellular calcium signaling.Methods:?1?the content of TRPV1 protein in different types of cells was detected by western blotting assay.?2?cell membranes were purified from different cell types using ultracentrifugation method and the modification method of membrane on Ti3C22D nanomaterial were optimized;?3?the composition,morphology,thickness,surface area and the absorbance of the cell membrane modified nanomaterials were characterized using a series of methods for nanomaterials;?4?the cytotoxicity effect of nanomaterials on cells was detected by CCK8 cytotoxicity method.?5?the intracellular Ca²⁺was probed by a calcium fluorescence indicator?Fluo-8 AM?and the relative calcium concentrations in cells was monitored by a live-cell imaging using a fluorescence microscope.Results:?1?ND7/23 neural cells expressed high level of the TRPV1 protein comparing with other three types of cells;?2?The cell membrane was successfully purified and modified the nanomaterials;?3?The intracellular calcium of cells with nanomaterials treatment were regulated by NIR light;?4?Skeletal muscle cell membrane modified nanomaterials efficient targeted neural cells with limited cytotoxicity;?5?Skeletal muscle cell membrane modified Ti₃C₂ 2D nanomaterials enabled the NIR light photothermal effect for precisely controlled cellular calcium signaling.Conclusion:We achieved the NIR light controlled cellular calcium signaling in neural cells via the selective regulation on TRPV1 channel protein using skeletal muscle cell membrane modified Ti3C2 2D nanomaterials.