MSC Extracellular Vesicles Reverse Ovarian Aging by Silencing Inflammation

Ovarian aging accelerates far faster than most other organ systems, causing fertility decline by the late 30s and complete reproductive cessation by the late 40s. Beyond reproduction, this process drives cardiovascular, skeletal, and neurological deterioration through hormonal loss. Current clinical options remain limited, making the search for ovarian-protective therapies urgent.

This study investigated whether EVs derived from UCMSCs — valued for their low immunogenicity, abundant supply, and strong proliferative capacity — could protect aging ovaries and, if so, how. Researchers isolated UCMSC-EVs via serial ultracentrifugation, confirmed their identity by nanoparticle tracking analysis, transmission electron microscopy, and EV surface markers (CD63, Alix), and characterized their protein cargo using LC-MS/MS proteomics. Two complementary aging models were used: naturally aged female C57BL/6J mice (treated with EVs from weeks 44–56) and D-galactose (D-gal)-induced aging mice, plus in vitro D-gal-treated human granulosa cell lines (SVOG and KGN).

UCMSC-EV treatment markedly improved ovarian histology in both animal models — increasing primordial, primary, secondary, and antral follicle counts, reducing fibrosis on Masson staining, and lowering apoptotic cell populations measured by AM/PI assay. CCK-8 and ROS assays confirmed improved granulosa cell viability and reduced oxidative stress in vitro. RNA sequencing of treated ovarian tissue pointed strongly toward suppression of inflammatory signaling as the dominant mechanism.

Proteomic profiling of UCMSC-EVs by LC-MS/MS revealed high abundance of LGALS3BP, a multifunctional extracellular glycoprotein previously linked to immune regulation and NF-κB modulation. The researchers demonstrated via western blotting that UCMSC-EVs deliver LGALS3BP into injured granulosa cells, reducing nuclear translocation of NF-κB p65 and suppressing downstream pro-inflammatory cytokines. Critically, when LGALS3BP was knocked down in UCMSCs using siRNA prior to EV collection (producing UCMSC-EV^si-LGALS3BP), the anti-inflammatory and regenerative benefits were substantially impaired in both cell cultures and mice — confirming LGALS3BP as the functional payload.

These findings establish a concrete molecular pathway linking MSC-EV cargo to ovarian protection: UCMSC-EVs → LGALS3BP delivery → NF-κB suppression → reduced inflammaging → preserved follicle pool and granulosa cell function. The work supports EV-based, cell-free therapeutics as a promising clinical direction for combating ovarian aging and its systemic downstream consequences, while pointing to LGALS3BP as a potential biomarker or therapeutic target in its own right.