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<article xlink="http://www.w3.org/1999/xlink" dtd-version="1.0"><Article><Journal><PublisherName>yemenjmed</PublisherName><JournalTitle>Yemen Journal of Medicine</JournalTitle><PISSN>c</PISSN><EISSN>o</EISSN><Volume-Issue>Volume 4 Issue 1</Volume-Issue><IssueTopic>Multidisciplinary</IssueTopic><IssueLanguage>English</IssueLanguage><Season>January- April 2025</Season><SpecialIssue>N</SpecialIssue><SupplementaryIssue>N</SupplementaryIssue><IssueOA>Y</IssueOA><PubDate><Year>2025</Year><Month>05</Month><Day>22</Day></PubDate><ArticleType>Article</ArticleType><ArticleTitle>The Silent Scream of Skin Cells: A Brief Review of Slow Electrical Signaling in the Epithelium</ArticleTitle><SubTitle/><ArticleLanguage>English</ArticleLanguage><ArticleOA>Y</ArticleOA><FirstPage>95</FirstPage><LastPage>104</LastPage><AuthorList><Author><FirstName>Mostafa Essam</FirstName><LastName>Eissa1</LastName><AuthorLanguage>English</AuthorLanguage><Affiliation/><CorrespondingAuthor>N</CorrespondingAuthor><ORCID/></Author></AuthorList><DOI>10.63475/yjm.v4i1.0039</DOI><Abstract>Epithelial cells, lining the skin and internal organs, play a crucial role as protective barriers and regulators of substance transport. Traditionally, these cells were not considered to employ electrical signaling for communication. However, recent investigations have unveiled that epithelial cells generate slow electrical signals, termed the "silent scream," in response to injury, thus challenging conventional views of intercellular communication. A recent experimental investigation provided compelling evidence for this phenomenon, demonstrating the ability of these cells to transmit electrical signals over considerable distances within the epithelium. The research utilized microelectrode array chips to precisely detect subtle electrical events in keratinocytes and Madin-Darby Canine Kidney (MDCK) cells, revealing spiking activity characterized by slow propagation speeds, distinct from the rapid action potentials of neurons. The mechanisms underlying this novel signaling are explored, focusing on the involvement of mechanosensitive ion channels, calcium signaling, and Adenosine triphosphate (ATP) release. Calcium ions, well-established intracellular messengers, appear to play a central role in this biological phenomenon. Integrating this newly discovered communication mode into the existing understanding of skin cell biology reveals a more intricate picture of how skin senses and responds to its environment. The implications of this finding extend to various facets of skin physiology and pathology, including wound healing, inflammation, and skin aging. In wound healing, where endogenous electric fields guide cell migration and promote repair, this unique type of electrical signaling potentially plays a crucial part. Furthermore, aberrant electrical signaling might contribute to chronic inflammatory conditions, and age-related changes in this signaling could underlie the functional decline observed in aged skin. The potential for other environmental stressors to trigger the epithelial-generated electric signals also warrants investigation. The exploration concludes by discussing potential technological applications, such as bioelectric sensors and enhanced wound healing therapies, and future research directions aimed at further elucidating the molecular mechanisms and functional roles of this non-excitable cell electrophysiology.</Abstract><AbstractLanguage>English</AbstractLanguage><Keywords>Adenosine triphosphate (ATP), Calcium Signaling, Cell Communication, Epithelial Cells, Keratinocytes, Wound Healing.</Keywords><URLs><Abstract>https://yemenjmed.com/admin/abstract?id=147</Abstract></URLs><References><ReferencesarticleTitle>References</ReferencesarticleTitle><ReferencesfirstPage>16</ReferencesfirstPage><ReferenceslastPage>19</ReferenceslastPage><References>SciTechDaily. Scientists Detect Silent and;ldquo;Screamand;rdquo; of Skin Cells for the First Time [Internet]. Monrovia (CA): SciTechDaily; 2025 [cited 2025 Apr 3]. 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