Injury Induced Connexin 43 Expression Regulates Endothelial Wound Healing

Sedovy, M. W.; Renton, M. C.; Roberts, K.; Leng, X.; Dennison, C.; Leaf, M.; Lampe, P. D.; Best, A. K.; Isakson, B.; Johnstone, S. R.

doi:10.1101/2025.02.24.639946

bioRxiv · 10.1101/2025.02.24.639946

Injury Induced Connexin 43 Expression Regulates Endothelial Wound Healing

Sedovy, M. W.·Renton, M. C.·Roberts, K.·Leng, X.·Dennison, C.·Leaf, M.·Lampe, P. D.·Best, A. K.·Isakson, B.·Johnstone, S. R.

View original source ↗Export metadata ↓

Abstract

Endothelial cell (EC) injury is a major contributing factor to vascular surgical failure. As such, understanding the mechanisms of endothelial healing is essential to the development of vascular therapeutics and procedures. Gap junctions formed by connexin 43 (Cx43) are implicated in regulating skin wound healing, but their role in endothelial healing is unknown. Secondary analysis of RNAseq data from in vivo injured mouse aortas (GEO: GSE115618), identified significant Cx43 upregulation in EC post-injury. We developed a novel in vivo model of EC injury using mouse carotid artery ligation to test the role of Cx43. We identified that EC immediately adjacent to the wound edge upregulate Cx43 protein expression, predominantly at cell-cell junctions. We show significantly delayed EC healing in a mouse model of inducible EC-specific Cx43 deletion (EC-Cx43 KO) at 24 hr post ligation. Single cell RNAseq analysis of 10,829 cells from 18 hr injured EC-WT and EC-Cx43 KO carotids revealed a Cx43-associated reduction in enrichment of EC pathways associated with migration, proliferation, and ERK/MAPK signaling pathways. Finally, the importance of Cx43 phosphorylation on EC healing was tested in mice with single-point alanine mutations (phospho-null) in known phosphorylation sites that alter Cx43 channel assembly and opening. Mice containing alanine mutations at ERK phosphorylated Cx43 serines (Cx43S255/262/279/282A) reduces healing rates similar to EC-Cx43 KO. These data suggest that EC injury-induced Cx43 upregulation, and subsequent Cx43 gap junction-mediated cell-to-cell communication are required for normal EC migration during wound healing after vascular injury. New and NoteworthyThese findings demonstrate for the first time that mechanical injury to large artery endothelium induces the expression of gap junction protein Cx43. This upregulation improves migratory and proliferative capacity of endothelial cells at the wound edge, facilitating timely wound closure. This phenomenon is dependent on appropriate gap junction function and turnover.

Source connections

Published article ↗

Explore related subjects

physiology Preprint

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

Sedovy, M. W., Renton, M. C., Roberts, K., Leng, X., Dennison, C., Leaf, M., Lampe, P. D., Best, A. K., Isakson, B., Johnstone, S. R.. 2025-03-01. Injury Induced Connexin 43 Expression Regulates Endothelial Wound Healing. https://doi.org/10.1101/2025.02.24.639946

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

28S-rsRNA facilitates PASMC proliferation through PKM2 β-hydroxybutyrylation

Ribosomal RNA-derived small RNAs (rsRNAs) are nucleic acid fragments originating from rRNA, the functions and roles of which in diseases remain incompletely understood. We identified 28S rsRNA-CTC_L20, an rsRNA whose expression is upregulated in hypoxic pulmonary artery smooth muscle cells (PASMCs) and in lung tissues of pulmonary hypertension (PH) models. In hypoxic cells, 28S rsRNA-CTC_L20 promotes PASMC proliferation, and its knockdown mitigates SuHx-induced pulmonary hypertension and vascular remodeling. Mechanistically, 28S rsRNA-CTC_L20 modulates {beta}-hydroxybutyrate (BHB) production by maintaining the stability of ketogenic enzyme mRNAs through its "CTGNNGG" motif. Elevated levels of BHB enhance the {beta}-hydroxybutyrylation modification at K166 of pyruvate kinase M2 (PKM2), increasing its activity and driving glycolysis to sustain proliferation. These results link ketone body metabolism to glycolysis in hypoxic cells and define an rsRNA-BHB-PKM2 {beta}-hydroxybutyrylation axis in PH. They also point to 28S rsRNA-CTC_L20 as a potential target for treating vascular remodeling.

physiology↗

bioRxiv2026

Selective activation of estrogen receptors modulates electrical activity and insulin secretion in human EndoC-βH1 cells

Estrogen receptors (ERs), ER and ER{beta} have important roles in the physiology of the endocrine pancreas in animal models, but the effects of ER activation on insulin-secreting human cells are still poorly understood. Here, we investigated the role of ER and ER{beta} as modulators of electrical activity and insulin secretion in the insulin-secreting human cell line EndoC-{beta}H1. Immunocytochemical analysis revealed a widespread cellular distribution of ER, while ER{beta} was predominantly localized outside the nucleus. We observed that both estradiol (E2) and the ER{beta} agonist diarylpropionitrile (DPN) led to a decrease in insulin secretion in the absence of stimulatory glucose concentrations, without affecting insulin content. Patch-clamp experiments revealed that a 48-hour treatment with either the ER agonist PPT or DPN resulted in depolarization of the resting membrane potential, increased action potential firing frequency, and altered the action potential waveform in EndoC-{beta}H1 cells. PPT increased voltage-dependent Ca2+ channel currents, while DPN reduced K+ and Na+ currents. These results suggest that activation of ER and ER{beta} modulates beta-cell electrical activity through distinct pathways involving ion channels. The effects of E2, PPT, and DPN were not caused by altered expression levels of ion channel genes after 48 hours of treatment. This suggests that these receptors act extranuclearly without affecting gene expression. Together, our findings demonstrate that selective activation of ER and ER{beta} modulates beta-cell excitability through distinct electrophysiological mechanisms and that E2 and DPN reduce basal insulin secretion in human EndoC-{beta}H1 cells. These results support ER and ER{beta} as potential targets for modulating human pancreatic beta-cell function.

physiology↗

bioRxiv2026

Body weight modifies the efficacy of lifespan-extending interventions in ad libitum-fed mice

Geroprotective interventions are often assessed by extension of lifespan in ad libitum-fed mice. Increased lifespan could therefore reflect rescue of adverse phenotypes of unhealthy controls. We analysed body weight and survival for 33,780 mice in the Interventions Testing Program (ITP) to test whether treatment effects varied with body weight. In males, each added standard deviation of attained adult weight made treatment 6% more favourable (HR 0.94), more apparent for interventions that lowered body weight (HR 0.90). Median lifespan increase rose from 6.2% in mice in the lightest quartile to 20.2% in the heaviest pre-dosing weight quartile among those experiments, mainly because control survival declined more steeply with weight than that of the intervention group. The effect of body weight was consistent across 13 of 14 compounds and reflected weight attained during adulthood rather than in early life. Weight-dependence of intervention effects was weak in ITP females, possibly because median survival of controls exceeded that of every sampled non-ITP female control group. Amelioration of weight-associated risk is therefore implicated as a major contributor to lifespan increases relative to heavy, short-lived controls. The geroprotective effects of these interventions may thus be less apparent in metabolically healthier mice or humans.

physiology↗