Chini, Eduardo N.

Renal water reabsorption is classically regulated by vasopressin V2 receptor (V2R) signaling through cyclic AMP and protein kinase A, driving apical accumulation of aquaporin-2 (AQP2). However, collecting duct water handling is also modulated by vasopressin-independent mechanisms. Here, we examined intracellular soluble urate as a vasopressin-independent regulator of AQP2 trafficking. Intracellular urate accumulation in collecting duct cells was mediated by enhanced apical urate uptake via GLUT9b and reduced apical urate efflux through ABCG2, triggering phosphodiesterase-4 activation, reduced cAMP, and downstream AMP-activated protein kinase (AMPK) activation. The resulting AQP2 accumulation at the apical membrane was independent of V2R signaling, required ongoing endocytosis, and was associated with features of postendocytic apical trafficking of internalized AQP2. In vivo ABCG2 inhibition with probenecid increased apical AQP2 abundance and markedly attenuated tolvaptan-induced polyuria in both wild-type and Pkd1 RC/RC autosomal dominant polycystic kidney disease (ADPKD) mice in a uricase-independent manner while preserving tolvaptan’s ADPKD-modifying efficacy. In a phase II trial with tolvaptan-treated patients with ADPKD, probenecid reduced urine volume and nocturia frequency. Together, these findings support a vasopressin-independent urate/AMPK/AQP2 pathway that regulates renal water handling and, in a preclinical ADPKD model, can uncouple cyst growth attenuation from the dose-limiting aquaretic effects of V2R antagonism.

BACKGROUND: Atherothrombosis, which underlies most acute coronary syndromes and is driven by intraplaque thrombosis, preferentially occurs in regions of disturbed blood flow (d-flow). Although LATS1/2 (large tumor suppressor kinases 1 and 2) are known regulators of endothelial mechanotransduction, the mechanisms by which d-flow connects endothelial senescence, proliferation, and intraplaque thrombosis remain poorly understood. METHODS: We investigated endothelial cell (EC)-specific roles of Lats1/2 using inducible EC-specific knockout mice in a partial carotid ligation model. Spatial multiomics of human and mouse plaques was performed using imaging mass cytometry, COMET sequential immunofluorescence, and spatial metabolomics. RESULTS: Tamoxifen-induced deletion of both Lats1 and Lats2 (homozygous) in ECs caused fatal edema and increased vascular permeability. In contrast, Lats1 het ( ± ) / Lats2 homo ( −/−) -EC-specific knockout mice survived and developed spontaneous atherothrombotic plaques with neovascularization. Spatial proteomics revealed that LATS1/2 loss induced a senescence-associated stemness phenotype driven by CD38 upregulation. Spatial metabolomics showed sulfite and taurine accumulation, indicating SUOX (sulfite oxidase) deficiency. CD38 suppressed SUOX, demonstrated a switch into the reverse mode of mitochondrial complex V, increased succinate dehydrogenase activity, and promoted ATP consumption. Despite ATP depletion, glutamate metabolism and the citric acid cycle flux increased, sustaining EC proliferation under energetic stress. This senescence-associated stemness state promoted both proliferation and senescence, leading to fragile, leaky neovessels and intraplaque thrombotic lesions. Pharmacological CD38 inhibition attenuated these phenotypes. Similar EC states were observed in human plaques. CONCLUSIONS: Loss of Lats1/2 in ECs induces a CD38-associated senescence-associated stemness-like phenotype that promotes intraplaque thrombosis through mitochondrial metabolic reprogramming, including changes consistent with reverse-mode operation of mitochondrial complex V. These findings define a mechanistic link between disturbed flow, endothelial metabolic reprogramming, and intraplaque thrombosis and hemorrhage.

Importance and Objective: Aging is a complex biological process uniquely shaped in women by hormonal transitions, particularly across the menopause transition. While chronological age alone fails to capture individual health variability, emerging molecular biomarkers offer tools to quantify biological aging and understand mechanisms underlying age-related decline. This review synthesizes the current landscape of aging biomarkers, including senescence-associated secretory phenotype factors, epigenetic clocks, clonal hematopoiesis of indeterminate potential, and telomere length, with a particular emphasis on their relevance to menopause. Methods: This narrative review synthesizes human studies, translational research, and foundational basic science identified through PubMed searches through June 2025, examining aging biomarkers in general populations, among women in the menopause transition, and in relation to vasomotor symptoms and hormone therapy. Discussion and Conclusion: Evidence demonstrates that changes in biological aging biomarkers are observed across multiple molecular systems during midlife, including the menopause transition, reflecting broader age-related biological remodeling. Postmenopausal status, particularly following early or surgical menopause, has been associated with biological aging phenotypes, including elevated senescence-associated secretory phenotype factors, epigenetic age acceleration, clonal hematopoiesis, and shorter leukocyte telomere length, likely reflecting a combination of chronological aging, hormonal changes, and individual biological vulnerability. While severe vasomotor symptoms have been linked to higher epigenetic age, hormone therapy may favorably influence certain senescence markers and biological age discrepancy. Despite these advances, significant limitations constrain clinical translation, as current biomarkers capture overlapping biological processes and lack validated thresholds to define biological aging, especially in women. Future research requires large, longitudinal studies across diverse populations to establish clinically meaningful thresholds and sex-specific calibration. Advancing precision health strategies for women requires a better understanding of how reproductive and hormonal factors modify biomarker trajectories to improve risk prediction and to facilitate the development of targeted interventions for age-related diseases.