{
  "id": 3529272,
  "title": "Subcellular pharmacology of a novel cell-permeable fluorescent phosphodiesterase inhibitor using advanced fluorescence microscopy",
  "url": "https://urgent.news/2026/08/26/subcellular-pharmacology-of-a-novel-cell-permeable-fluorescent",
  "topic": "health",
  "section": "Health & Medicine",
  "published": "2026-08-26T00:00:00.000Z",
  "source": {
    "name": "bioRxiv",
    "slug": "biorxiv",
    "url": "https://www.biorxiv.org/content/10.64898/2026.08.22.746441v1?rss=1"
  },
  "original_language": "en",
  "account": "Direct observation of drug interaction with its target within living cells has long been a significant challenge. In this work, researchers create a cell-permeable fluorescent analog of the phosphodiesterase 4 (PDE4) inhibitor rolipram, termed MAN193. This novel probe is created by attaching fluorescein diacetate to the inhibitor. Once activated intracellularly, the probe acts as a near-neutral PDE4 antagonist, enabling direct visualization of endogenous PDE4 populations. Advanced fluorescence spectroscopy imaging methods, including molecular brightness analysis and fluorescence anisotropy imaging, are employed to demonstrate the rolipram-displaceable binding of the probe to cytosolic PDE4. This reveals the subcellular distribution of binding sites. Furthermore, the probe is used to visualize untagged PDE4 at focal adhesion complexes in cardiomyocyte-like cells, highlighting its potential to map intracellular drug-target engagement with subcellular resolution. This innovative approach establishes fluorogenic drug conjugation combined with quantitative spectroscopy imaging as a versatile strategy for studying the spatial pharmacology of small molecules in living systems.",
  "summary": "Direct visualisation of drug-target engagement within living cells remains a major challenge. Here we develop a cell-permeable fluorogenic analogue of the phosphodiesterase 4 (PDE4) inhibitor rolipram (MAN193), generated by conjugation to fluorescein diacetate. Following intracellular activation, the probe functions as a near-neutral PDE4 antagonist and enables direct visualisation of endogenous…",
  "key_points": [],
  "editors_take": null,
  "illustration": null,
  "coverage": {
    "outlets": 1,
    "also_reported_by": []
  },
  "ai_generated": true,
  "disclaimer": "Summaries, key points and the editor’s take are written by software from other outlets’ reporting and may contain errors — always check the linked original."
}