Résumé
In the heart, the cardiac function is regulated by the autonomic nervous system (ANS) that extends through the myocardium and establishes junctions at the sinus node and ventricular levels. The ANS exerts a trophic action during the development and under cardiac pathologies. Increase or decrease of the neuronal activity directly affects myocardial function and its structure through remodelling processes. These attacks can be associated with diabetes, sympathetic hyper-innervation or infection of the stellate ganglia, the major sympathetic ganglion for cardiac regulation.
The neuro-cardiac junction is poorly understood, also due to a lack of pertinent models. The main objective of this project is the development of a neuro-cardiac organ-on-chip to investigate the impact of neurons on cardiomyocytes and further understand the neuro-cardiac junction.
We use microfluidic devices with separated cell compartments and microchannels to cultivate neurons and cardiomyocytes and allow the neuronal extensions reaching the cardiomyocytes. At first, rat PC12 cells, which recapitulate characteristics of sympathetic neurons, are cultivated with human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs). A functional and structural characterization of the neuro-cardiac organ-on-chip using immunofluorescence, fluorescent confocal microscopy and video-edge capture.
PC12 cells are able to differentiate and project from neural compartment to cardiac compartment to create connection with hiPSC-CMs. We confirmed the presence of specialized structures between the two cell types that allow neuromodulation. The specific stimulation of neuronal cell impact directly cardiac activity such as calcium kinetics without modulating the cardiac contractility.
By using innovative approaches, we developed a neuro-cardiac organ-on-a-chip that recapitulate both structural and functional properties of the neuro-cardiac junction. This work may contribute to a better understanding of the interaction between the ANS and heart.