) Live and intact cornea maintains an electric potential difference across the epithelium, the transepithelial potential difference (TEP). The compromised epithelial barrier in corneal wounds collapses the transepithelial potential at the wound site, resulting in naturally occurring endogenous electric fields that point towards the wound center from adjacent intact tissues. These naturally occurring wound electric fields (wEFs) provide powerful signals that stimulate and guide cells to migrate into the wound to initiate healing. We demonstrated that these electrical signals could override other directional cues, such as injury stimulation, free edge and mechanical forces, in guiding migration of corneal epithelial sheets and large groups of cells. Our long term goal is to elucidate the molecular mechanisms that generate and regulate the wound electric fields, i.e. to discover the ?molecular generators?, and to use this knowledge to develop new therapeutic strategies to collectively mobilize cells (tissues) to heal chronic wounds and non-healing wounds. Our previous research has identified key ionic mechanisms and ?molecular generators? that produce and regulate wEFs. Importantly, we demonstrated in three diabetic models that wEFs are defective and this correlates very well with impaired healing. Using high throughput screens, we also identified novel molecular mechanisms directing the responses of human corneal epithelial cells (CECs) to physiological electric fields. In this application, we will dissect the defective electrical signaling and impaired responses of epithelial cells in diabetic cornea. We therefore propose a comprehensive study to (1) elucidate ionic mechanisms underlying defective electrical signaling in diabetic corneal wounds, and to build a mathematical model that simulates wound electric fields; (2) determine how high glucose and oxygen uptake regulate electrogenic machinery, and how these mechanisms are impaired in diabetic cornea. Through completion of these aims, our goal is Aim (3) to electrically facilitate healing of diabetic wounds by correcting defects in generation of electrical signals.

Public Health Relevance

Injuries to cornea that break the epithelial barrier produce naturally occurring wound electric fields which provide a powerful signal to mobilize and guide migration of corneal epithelial cells into the wound to cause healing. Our research has identified the ?molecular generators? that produce and regulate the wound electric currents. Importantly, we discovered that the wound electrical signal is defective in diabetic cornea and correlates with impaired healing. In this proposal, we will investigate how this mechanism goes awry in diabetic cornea and aim to develop a strategy to correct the defect to achieve better healing of diabetic wounds.

Agency
National Institute of Health (NIH)
Institute
National Eye Institute (NEI)
Type
Research Project (R01)
Project #
3R01EY019101-09S1
Application #
9928754
Study Section
Program Officer
Mckie, George Ann
Project Start
2009-12-01
Project End
2020-02-29
Budget Start
2019-05-14
Budget End
2020-02-29
Support Year
9
Fiscal Year
2019
Total Cost
Indirect Cost
Name
University of California Davis
Department
Dermatology
Type
Schools of Medicine
DUNS #
047120084
City
Davis
State
CA
Country
United States
Zip Code
95618
Tai, Guangping; Tai, Michael; Zhao, Min (2018) Electrically stimulated cell migration and its contribution to wound healing. Burns Trauma 6:20
Sun, Xiaoyan; Qi, Hongsheng; Zhang, Xiuzhen et al. (2018) Src activation decouples cell division orientation from cell geometry in mammalian cells. Biomaterials 170:82-94
Sun, Yao-Hui; Sun, Yuxin; Zhu, Kan et al. (2018) Electric fields accelerate cell polarization and bypass myosin action in motility initiation. J Cell Physiol 233:2378-2385
Feng, Jun-Feng; Liu, Jing; Zhang, Lei et al. (2017) Electrical Guidance of Human Stem Cells in the Rat Brain. Stem Cell Reports 9:177-189
Zhang, Yan; Xu, Guoqing; Lee, Rachel M et al. (2017) Collective cell migration has distinct directionality and speed dynamics. Cell Mol Life Sci 74:3841-3850
Nakajima, Ken-Ichi; Zhao, Min (2016) Concerted action of KCNJ15/Kir4.2 and intracellular polyamines in sensing physiological electric fields for galvanotaxis. Channels (Austin) 10:264-6
Zhu, Kan; Sun, Yaohui; Miu, Anh et al. (2016) cAMP and cGMP Play an Essential Role in Galvanotaxis of Cell Fragments. J Cell Physiol 231:1291-300
Shen, Yunyun; Pfluger, Trisha; Ferreira, Fernando et al. (2016) Diabetic cornea wounds produce significantly weaker electric signals that may contribute to impaired healing. Sci Rep 6:26525
Sun, Yao-Hui; Sun, Yuxin; Zhu, Kan et al. (2016) An Experimental Model for Simultaneous Study of Migration of Cell Fragments, Single Cells, and Cell Sheets. Methods Mol Biol 1407:251-72
Gao, Runchi; Zhao, Siwei; Jiang, Xupin et al. (2015) A large-scale screen reveals genes that mediate electrotaxis in Dictyostelium discoideum. Sci Signal 8:ra50

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