Deactivation of androgen receptor with aging shows a link to mitochondrial dysfunction in mice cortical microvessels

Background: Androgens facilitate their effects via binding to the specific androgen receptors (AR) and AR activation supports neurogenesis, cognitive function in aging, and induction of neuroprotective pathways. Conversely, AR inhibition promotes several neurological diseases including dementia. AR-mediated pathophysiology in brain microvasculature with aging is poorly understood. We have identified proteins involved in AR deactivation and mitochondrial dysfunction with aging in mice brain microvessels. Methods: Cortical microvessels (MVs: end-arterioles, capillaries, and venules) were isolated from equal numbers of male and female, young (4–6 months) and old (20–21 months) mice (n = 6/group) and proteomics analysis was performed by liquid chromatography/mass spectrometry. Ingenuity pathway analysis (IPA) was used to identify the differentially expressed proteins (DEPs) involved in AR deactivation and mitochondrial dysfunction in old vs. young mice MVs. In vitro studies established the link between deactivation of AR and mitochondrial dysfunction. Results: We quantified 4746 and 4579 DEPs by proteomics in cortical MVs of young and old mice, respectively. Protein-protein interaction analysis revealed that 205 DEPs (62 upregulated and 143 downregulated) were associated with AR deactivation in both male and female old and young mice. Hierarchical cluster analysis of the top 50 AR deactivation-related DEPs indicated no sex-specific differences between old male and female mice. IPA showed that several AR deactivation-related DEPs were associated with activation of mitochondrial dysfunction, possibly due to deactivation of oxidative phosphorylation (OXPHOS), respiratory electron transport, complex IV assembly, and mitochondrial division signaling pathways. Interactome analysis showed that AR deactivation led to cytochrome c oxidase, cytochrome bc1, ATP1A3, ATP51A, and dynamin-related protein 1 (DRP1) protein inhibition, which established a direct link between AR deactivation and mitochondrial dysfunction. In vitro studies indicated that loss of AR by small molecule, bardoxolone methyl in primary human brain microvascular endothelial cells (hBMECs) significantly decreased the expression of pDRP1 (Ser616 and Ser637), and OXPHOS-related complex I (NDUFB8), complex II (SDHB), and complex III (UQCRC2) proteins. Conversely, the downregulation of DRP1 by shRNA significantly decreased the AR expression in primary hBMECs. Conclusions: Our results suggest that deactivation of AR leads to protein expression profile changes that affect DRP1-dependent mitochondrial biogenesis and OXPHOS, which leads to endothelial dysfunction in the brain microvasculature with aging. NIH: AG075988 (DWB), HL148836 (DWB), AG063345 (DWB), R01AG083567 (IR-G), R01NS136041 (PKC), R01NS114286 (PVGK and RM), and R01AG074489 (PVGK and RM). This abstract was presented at the American Physiology Summit 2025 and is only available in HTML format. There is no downloadable file or PDF version. The Physiology editorial board was not involved in the peer review process.