Alpha-Klotho-Deficient Female Mice Exhibit Estrogen Metabolic Dysregulation and a Premature Ovarian Insufficiency-Like Phenotype

Mol Cell Endocrinol. 2026 Mar 13:112787. doi: 10.1016/j.mce.2026.112787. Online ahead of print.

ABSTRACT

BACKGROUND: Premature ovarian insufficiency (POI) is characterized by early loss of ovarian function, hypoestrogenism, and infertility. α-Klotho, an aging-suppressor protein, has been implicated in reproductive aging, but its role in POI and ovarian steroidogenesis remains unclear.

METHODS: Systemic α-Klotho KO female mice and age-matched WT were evaluated by ovarian histology, estrous cycle monitoring, serum hormone ELISA, RNA sequencing, qPCR, immunofluorescence, and western blotting to assess ovarian morphology, gonadotropin signaling, and estrogen steroidogenic pathways. α-Klotho was knocked down in KGN cells and primary human granulosa cells (hGCs). Transcriptomic and untargeted metabolomic profiling, together with qPCR, WB, and E2 ELISA tests, were used to assess steroidogenic enzyme expression and metabolic alterations.

RESULTS: α-Kl-deficient female mice exhibited a POI-like phenotype, including reduced ovarian size and weight, broad follicle depletion with increased atresia, persistently diestrus estrous status (10-12 weeks), and markedly decreased serum E2. Serum LH and FSH, ovarian LHR, FSHR and early steroidogenic enzymes was also downregulated in α-Kl KO female mice. While α-Kl knockdown in KGN cells and primary hGCs caused only limited changes in key granulosa-cell steroidogenic markers and did not significantly impair FSH-stimulated E2 accumulation in androgen-supplemented hGCs cultures. KGN transcriptomic and metabolomic analyses mainly indicated inflammatory and broad metabolic reprogramming rather than robust estrogen-biosynthesis pathway disruption.

CONCLUSION: α-Klotho deficiency is associated with severe in vivo ovarian steroidogenic dysfunction and a POI-like phenotype, whereas in vitro granulosa-cell α-KL knockdown shows limited direct effects on E2 steroidogenic machinery, supporting a association with HPO-axis and gonadotropin downregulation.

PMID:41833629 | DOI:10.1016/j.mce.2026.112787