{"version":"v1","chain":{"id":"lps-aromatase-paradox","title":"Gut LPS → granulosa TLR4 → follicular aromatase suppression","question":"How could gut barrier dysfunction plausibly impair egg quality despite normal serum hormones?","summary":"LPS translocation activates TLR4 on granulosa cells; locally produced TNF-α and IL-1β suppress FSH-driven CYP19A1, lowering intra-follicular estrogen even when serum estradiol appears normal.","steps":[{"nodeId":"concept:gut-barrier-dysfunction","rationale":"Tight-junction loss permits LPS translocation.","evidence":"established","claimIds":["lps-translocation-via-tlr4-drives-low-grade-endotoxemia"]},{"nodeId":"molecule:lps","rationale":"Circulating LPS reaches the ovarian follicle in low-grade endotoxemia.","evidence":"mechanistic-inference"},{"nodeId":"pathway:tlr4","rationale":"Granulosa cells express TLR4; activation triggers MyD88/NF-κB.","evidence":"established"},{"nodeId":"pathway:nf-kb","rationale":"Local TNF-α and IL-1β are induced inside the follicle.","evidence":"established"},{"nodeId":"article:how-dysbiosis-disrupts-hormonal-health-ovulation-and-egg-qua","rationale":"FSH-stimulated CYP19A1 expression is suppressed; intra-follicular estradiol falls.","evidence":"mechanistic-inference","claimIds":["lps-tlr4-suppresses-granulosa-aromatase","dysbiosis-impairs-egg-quality-via-aromatase-paradox"]}],"competingChains":["primary-ovarian-aging-chain"],"relatedConcepts":["gut-barrier-dysfunction"],"relatedArticles":["how-dysbiosis-disrupts-hormonal-health-ovulation-and-egg-qua"],"evidenceFloor":"hypothesis","lastReviewed":"2026-05-11"}}