Limosilactobacillus reuteri enhances ovarian function and female fertility.

Limosilactobacillus reuteri Y15 (LRY15)-derived polyunsaturated fatty acids (PUFAs) restore follicular cell-cell junctions and fertility. LRY15, isolated from the intestine of alginate oligosaccharides (AOS)-dosed mice, improves ovarian function and fertility in cisplatin-induced subfertile mice. LRY15 produces PUFAs, whereas deletion of holo-acyl carrier protein synthase (AcpS) in LRY15 reduces PUFA synthesis and weakens its protective effects. Docosahexaenoic acid (DHA) supplementation recapitulates LRY15-mediated improvements in follicle and embryo development. Stereo-seq analysis reveals that LRY15 restores ovarian cell-cell junctions, suggesting junction remodeling as an important cellular process associated with LRY15 treatment. The Fads2-deficient mouse model further validates that LRY15-derived PUFAs restore follicular junction integrity and improve fertility.