Neuroprotective effect of corn silk (Zea mays L.) and its isolated compounds in neurodegenerative diseases: a review of pre-clinical studies.

Corn silk (CS), largely known as Stigma maydis, has long been used in traditional medicine and beyond. Some previous studies suggested that CS contains bioactive compounds of interest to treat neurodegenerative diseases. We systematically evaluated the scientific evidence from pre-clinical studies concerning the neuroprotective effect of CS and the compounds found in this plant. We included 20 studies in our analysis out of the 227 studies identified (until January 2024). In vitro, results indicate the beneficial effects of the administration of CS extracts or isolated compounds, such as isoorientin (ISO), by inhibiting acetylcholinesterase and butyrylcholinesterase enzymes, oxidative stress, cytotoxicity, and other mechanisms related to neuronal damage. Four in vivo studies also demonstrated the beneficial effects of ISO, although we detected a considerable risk of bias. CS and its isolated compounds (mainly ISO and maysin) protect against neurodegenerative diseases by interfering with mechanisms such as apoptosis, cellular interactions, and oxidative stress.