OR29-08 Testosterone produces different metabolic actions at low and high concentrations via extranuclear monomeric or nuclear dimeric androgen receptors

Disclosure: J.B. Kharlyngdoh: None. C.M. Gorvin: None. S. Siebel: None. R. Kibbey: None. F. Mauvais-Jarvis: None.

We previously showed that dihydrotestosterone (DHT) potentiates glucose-stimulated insulin secretion (GSIS) from mouse and human β cells through an extranuclear androgen receptor (AR) that amplifies GLP-1 insulinotropic action (Navarro et al. 2016). DHT activates a membrane AR to enhances GLP-1 receptor (GLP1-R)-mediated cAMP production at the plasma membrane and endosomes, via direct AR-GLP1-R interaction and AR activation of the bicarbonate sensor (HCO3^-) and soluble isoform of adenylate cyclase (sAC) (Xu et al. 2023). Here, using confocal microscopy and subcellular fractionation, we observed that AR and sAC are localized in the mitochondria of INS-1 832/3 β cells, suggesting a direct role of AR in mitochondrial localized sAC activation and cAMP production. We observe that DHT enhances mitochondrial cAMP production and increase GSIS from INS-1 cells in the presence of a phosphodiesterase inhibitor that prevents cAMP degradation. Using immunoprecipitation (IP)-based proteomics in INS-1 cells, DHT triggered AR interaction with 1) mitochondrial pyruvate dehydrogenase (PDH) to increase CO2 production and conversion to HCO3^- to activate sAC, and 2) mitochondrial ribosomal proteins involved in mitochondrial translation. Additionally, combining NanoBiT luciferase, phosphoproteomics, transcriptomics and fluxomics, we observe that 1) at low DHT concentrations corresponding to a hypogonadal male (max 0.1nM), DHT signals via extranuclear monomeric AR to increase Src and Akt phosphorylation and to increase glycolysis fluxes; 2) at higher DHT concentrations corresponding to a eugonadal male (0.3nM to 10nM), DHT increases AR dimerization and nuclear (and mitochondrial) gene transcription. Additionally, DHT dose dependently increases PDH flux and activity as well as TCA intermediates at 0.1nM and 10nM suggesting involvement of both monomeric and dimeric AR. In summary, depending on its concentration, testosterone activates either a monomeric or a dimeric AR that are distinct functional entities and regulate different signaling pathways and metabolic responses in male pancreatic β cells. References: Navarro et al. Extranuclear actions of the androgen receptor enhance glucose-stimulated insulin secretion in the male. Cell Metabol. 2016; 23:837-851. Xu et al. Architecture of androgen receptor pathways amplifying glucagon-like peptide-1 insulinotropic action in male pancreatic beta cells. Cell Rep. 42, 112529 (2023).

Presentation: Monday, July 14, 2025