Electric Phenomenon: A Disregarded Tool in Tissue Engineering and Regenerative Medicine

The human body contains endogenous electrical currents due to the flow of ions. Electrical fields generated across cell membranes are involved in cell migration, proliferation, and differentiation, and the repair and regeneration of tissues. Electroactive biomaterials incorporating metals, metalloids, graphene and graphene derivatives, conductive polymers, and piezoelectric polymers have low resistivity. Cell behaviors, such as attachment, migration, proliferation, and differentiation, are enhanced in electroactive biomaterials. The synchronous contractibility of skeletal muscle and cardiac excitable cells can be modulated by applying external electrical fields. Stem cells can be differentiated towards cardiac, skeletal muscle, neurogenic, or osteogenic lineages by applying specific external electrical fields even without the use of differentiation cell culture media. Tissue engineering and regenerative medicine (TERM) are paving the way to the generation of functional and mature biological tissues that closely emulate cellular, biochemical, and mechanical cues. Electrical fields in the human body modulate myriad biological processes, such as synapses, muscle contraction, hearing, and wound healing, which were disregarded in TERM until recently. To preserve and improve tissue electrophysiology, cells can be loaded in electroactive biomaterials and stimulated with exogenous electrical fields. Here, we review how electrical stimulation and electroactive biomaterials can be used to instruct cells to create more mature and functional tissue-engineered constructs. We also highlight the most recent electroactive engineered tissues developed for TERM. Tissue engineering and regenerative medicine (TERM) are paving the way to the generation of functional and mature biological tissues that closely emulate cellular, biochemical, and mechanical cues. Electrical fields in the human body modulate myriad biological processes, such as synapses, muscle contraction, hearing, and wound healing, which were disregarded in TERM until recently. To preserve and improve tissue electrophysiology, cells can be loaded in electroactive biomaterials and stimulated with exogenous electrical fields. Here, we review how electrical stimulation and electroactive biomaterials can be used to instruct cells to create more mature and functional tissue-engineered constructs. We also highlight the most recent electroactive engineered tissues developed for TERM. alteration of the membrane potential (membrane depolarization followed by repolarization) of excitable cells owed to the opening of voltage-gated ion channels. electric fields in the human body that modulate the behavior of cells and tissues. difference of electric potential between two points. ability of a biomaterial to conduct electrical current; is inversely proportional to the resistivity. total opposition to the motion of electrons in response to an alternating current. Impendence comprises a real part: the resistance (R): and an imaginary part: the reactance (X). inertia against the motion of electrons due to inductance (L) and capacitance (C). friction against the motion of electrons in response to a direct current (DC). resistance of a biomaterial to conduct electricity. ability of a biomaterial to store energy in the form of a magnetic and/or electric field. electric fields existing across cell membranes owing to the difference in ion concentration inside and outside the cell. electric current that accumulates in materials upon application of mechanical stress.