bioRxiv Science⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/2025.04.22.649788

EGFR activation in cholangiocytes promotes extrahepatic bile duct regeneration after injury

Calder, A. N.·Sakaguchi, T.·Peter, M.·Tobias, J.·Frankel, T.·Razumilava, N.
View original source ↗Export metadata ↓

Abstract

Background & AimsThe epidermal growth factor (EGF) receptor family of tyrosine kinases regulates development and homeostasis of digestive organs including the liver and bile ducts. It consists of four receptors, EGF receptor (EGFR) and erythroblastoma oncogene B 2-4 (ERBB2-4), and their corresponding ligands. EGF signaling promotes intrahepatic cholangiocyte proliferation, bipotent cell transdifferentiation into cholangiocytes, bile duct branching, and cholangiocarcinoma (CCA) aggressiveness. The EGF family signaling contribution to extrahepatic bile duct (EHBD) regeneration is not well defined. This work is aimed at determining the fundamental role of the EGF signaling network in the biliary proliferative response to EHBD obstruction. ApproachWe used mouse bile duct ligation to model obstructive EHBD injury, and human and mouse EHBD organoids for in vitro studies. We tested activating and inhibitory paradigms with recombinant EGF family ligands and receptor antagonists. Transcriptomic and immunohistochemistry analyses informed EGF signaling changes and cellular localization at homeostasis and after obstruction. ResultsAt homeostasis, the EHBD expressed EGFR ligands Tgfa, Btc, Hb-egf and Nrg4 in cholangiocytes, and Egf in stromal cells. Erbb2 and Erbb3 were predominant receptors expressed in cholangiocytes and Egfr in stromal cells at baseline. After EHBD obstruction, injury-induced biliary hyperproliferation was associated with increased abundance of Areg, Hb-egf, Tgf and Btc ligands and Egfr receptor in cholangiocytes with resulting epithelial EGFR activation. In biliary organoids, EGFR ligands induced organoid growth, and inhibition of EGFR, but not ERBB2, dampened cholangiocyte proliferation. Accordingly, EGFR inhibition in mice led to a decrease in the biliary proliferative response after EHBD obstruction. ConclusionThe obstruction-induced biliary proliferation is an EGFR-mediated response suggesting context-and receptor-specific EGF signaling network involvement in EHBD regeneration after injury.

Source connections

Explore related subjects

physiologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Calder, A. N., Sakaguchi, T., Peter, M., Tobias, J., Frankel, T., Razumilava, N.. 2025-04-29. EGFR activation in cholangiocytes promotes extrahepatic bile duct regeneration after injury. https://doi.org/10.1101/2025.04.22.649788

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↗