{
  "$type": "site.standard.document",
  "bskyPostRef": {
    "cid": "bafyreidq7voctjiqnryeia53ekw2utgph3wib5rasi2mgrzqdxiltd6duy",
    "uri": "at://did:plc:2gbt2dlwaqovtnmxkat3tyke/app.bsky.feed.post/3mfplxpi6r532"
  },
  "coverImage": {
    "$type": "blob",
    "ref": {
      "$link": "bafkreigz3klyxi6yy3drzqeejzov5lweaicajg6tu4e7xyj3iysa6dgh2u"
    },
    "mimeType": "image/jpeg",
    "size": 255528
  },
  "path": "/articles/d41586-026-00515-x",
  "publishedAt": "2026-02-25T21:13:55.979Z",
  "site": "https://www.nature.com",
  "tags": [
    "doi:10.1038/d41586-026-00515-x"
  ],
  "textContent": "Nature, Published online: 25 February 2026; doi:10.1038/d41586-026-00515-x\n\nA protein reinforces the blood–brain barrier, which becomes leaky with age.",
  "title": "How an exercise-activated enzyme helps to keep the brain young",
  "updatedAt": "2026-02-25T00:00:00.000Z"
}