Skin commensals shape the clock-ferroptosis axis to preserve barrier function in psoriasis.

Lactobacillus plantarum and its metabolite indole-3-lactic acid restore skin barrier function by modulating the clock-ferroptosis axis in psoriasis.

• Why it matters: Psoriasis involves disrupted skin microbiota and impaired barrier function, but the mechanisms linking microbiota to barrier repair remain unclear, limiting targeted therapies.
• What they did: The study identified reduced Lactobacillus in psoriatic skin and demonstrated that topical L. plantarum alleviates lesions by producing ILA, which restores keratinocyte circadian rhythms and inhibits ferroptosis.
• The result: This work reveals that skin microbiota influence barrier repair via circadian and ferroptosis pathways, suggesting L. plantarum and ILA as promising treatments for psoriasis.