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Electrical stimulation of existing three-dimensional bioprinted tissues to alter tissue activities is typically associated with wired delivery, invasive electrode placement, and potential cell damage, minimizing its efficacy in cardiac modulation. Here, we report an optoelectronically active scaffold based on printed gelatin methacryloyl embedded with micro-solar cells, seeded with cardiomyocytes to form light-stimulable tissues. This enables untethered, noninvasive, and damage-free optoelectronic stimulation–induced modulation of cardiac beating behaviors without needing wires or genetic modifications to the tissue solely with light. Pulsed light stimulation of human cardiomyocytes showed that the optoelectronically active scaffold could increase their beating rates (>40%), maintain high cell viability under light stimulation (>96%), and negligibly affect the electrocardiogram morphology. The seeded scaffolds, termed optoelectronically active tissues, were able to successfully accelerate heart beating in vivo in rats. Our work demonstrates a viable wireless, printable, and optically controllable tissue, suggesting a transformative step in future therapy of electrically active tissues/organs.
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This content will become publicly available on December 1, 2025
Bioelectric stimulation controls tissue shape and size
Abstract Epithelial tissues sheath organs and electro-mechanically regulate ion and water transport to regulate development, homeostasis, and hydrostatic organ pressure. Here, we demonstrate how external electrical stimulation allows us to control these processes in living tissues. Specifically, we electrically stimulate hollow, 3D kidneyoids and gut organoids and find that physiological-strength electrical stimulation of ∼ 5 - 10 V/cm powerfully inflates hollow tissues; a process we call electro-inflation. Electro-inflation is mediated by increased ion flux through ion channels/transporters and triggers subsequent osmotic water flow into the lumen, generating hydrostatic pressure that competes against cytoskeletal tension. Our computational studies suggest that electro-inflation is strongly driven by field-induced ion crowding on the outer surface of the tissue. Electrically stimulated tissues also break symmetry in 3D resulting from electrotaxis and affecting tissue shape. The ability of electrical cues to regulate tissue size and shape emphasizes the role and importance of the electrical micro-environment for living tissues.
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- Award ID(s):
- 2046977
- PAR ID:
- 10583751
- Editor(s):
- Anonymous
- Publisher / Repository:
- Nature Communications
- Date Published:
- Journal Name:
- Nature Communications
- Edition / Version:
- 1
- Volume:
- 15
- Issue:
- 1
- ISSN:
- 2041-1723
- Page Range / eLocation ID:
- 20-30
- Subject(s) / Keyword(s):
- Bioelectricity, organoids, electroinflation, hydrostatic pressure
- Format(s):
- Medium: X Size: 10MB Other: PDF
- Size(s):
- 10MB
- Sponsoring Org:
- National Science Foundation
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