Impact of the controlled release of a connexin 43 peptide on corneal wound closure in an STZ model of type I diabetes.
The alpha-carboxy terminus 1 (αCT1) peptide is a synthetically produced mimetic modified from the DDLEI C-terminus sequence of connexin 43 (Cx43). Previous research using various wound healing models have found promising therapeutic effects when applying the drug, resulting in increased wound healing rates and reduced scarring. Previous data suggested a rapid metabolism rate in vitro, creating an interest in long term release. Using a streptozotocin (STZ) type I diabetic rat model with a surgically induced corneal injury, we delivered αCT1 both directly, in a pluronic gel solution, and in a sustained system, using polymeric alginate-poly-l-ornithine (A-PLO) microcapsules (MC). Fluorescent staining of wound area over a 5 day period indicated a significant increase in wound closure rates for both αCT1 and αCT1 MC treated groups, withαCT1 MC groups showing the most rapid wound closure overall. Analysis of inflammatory reaction to the treatment groups indicated significantly lower levels of both Interferon Inducible T-Cell Alpha Chemoattractant (ITAC) and Tumor Necrosis Factor Alpha (TNFα) markers using confocal quantification and ELISA assays. Additional analysis examining genes selected from the EMT pathway using RT-PCR and Western blotting suggested αCT1 modification of Transforming Growth Factor Beta 2 (TGFβ2), Keratin 8 (Krt8), Estrogen Receptor 1 (Esr1), and Glucose Transporter 4 (Glut4) over a 14 day period. Combined, this data indicated a possible suppression of the inflammatory response by αCT1, leading to increased wound healing rates.
University of South Carolina School of Medicine, Columbia, South Carolina, United States of America.
Keith
K
Moore
FirstString Research Inc., Mount Pleasant, South Carolina, United States of America ; Medical University of South Carolina, Charleston, South Carolina, United States of America.
Gautam
G
Ghatnekar
Virginia Polytechnic and State University Carilion, Roanoke, Virginia, United States of America.
Robert G
RG
Gourdie
University of South Carolina School of Medicine, Columbia, South Carolina, United States of America.
Jay D
JD
Potts
D000818:Animals; D015415:Biomarkers / Q000032:analysis; D015153:Blotting, Western; D002214:Capsules; D018031:Connexin 43 / Q000378:metabolism*; D003316:Corneal Diseases / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D003692:Delayed-Action Preparations; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D003922:Diabetes Mellitus, Type 1 / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D004797:Enzyme-Linked Immunosorbent Assay; D058750:Epithelial-Mesenchymal Transition; D051275:Glucose Transporter Type 4 / Q000235:genetics / Q000378:metabolism; D007249:Inflammation / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D008297:Male; D010446:Peptide Fragments / Q000494:pharmacology*; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D017207:Rats, Sprague-Dawley; D060888:Real-Time Polymerase Chain Reaction; D020133:Reverse Transcriptase Polymerase Chain Reaction; D014945:Wound Healing
D015415:Biomarkers; D002214:Capsules; D018031:Connexin 43; D003692:Delayed-Action Preparations; D051275:Glucose Transporter Type 4; D010446:Peptide Fragments; D012333:RNA, Messenger; C495694:Slc2a4 protein, rat