Progesterone and allopregnanolone attenuate blood-brain barrier dysfunction following permanent focal ischemia by regulating the expression of matrix metalloproteinases

Exp Neurol. 2010 Nov;226(1):183-90. doi: 10.1016/j.expneurol.2010.08.023. Epub 2010 Sep 15.


Blood-brain barrier (BBB) breakdown after stroke is linked to the up-regulation of metalloproteinases (MMPs) and inflammation. This study examines the effects of progesterone (PROG) and its neuroactive metabolite allopregnanolone (ALLO) on BBB integrity following permanent middle cerebral artery occlusion (pMCAO). Rats underwent pMCAO by electro-coagulation and received intraperitoneal injections of PROG (8 mg/kg), ALLO (8 mg/kg) or vehicle at 1 h post-occlusion and then subcutaneous injections (8 mg/kg) at 6, 24, and 48 h. MMP activation and expression were analyzed by Western blot, immunohistochemistry and gelatin zymography 72 h post-pMCAO. Occludin1, claudin5, tumor necrosis factor-alpha (TNF-α) and Interleukin-6 (IL-6) were analyzed at 72 h post-pMCAO with Western blots. BBB permeability was measured by Evans blue extravasation and infarct size was evaluated by cresyl violet at 72 h after pMCAO. Ischemic injury significantly (p<0.05) increased the expression of MMP-9, MMP-2, TNF-α and IL-6, and reduced the levels of occludin1 and claudin5. These changes were followed by increased infarct size (% contralateral hemisphere) and Evans blue extravasation into the brain indicating compromise of the BBB. PROG and ALLO attenuated BBB disruption and infarct size following pMCAO by reducing MMPs and the inflammatory response and by preventing the degradation of occludin1 and claudin5. We conclude that PROG and ALLO can help to protect BBB disruption following pMCAO.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blood-Brain Barrier / drug effects*
  • Blood-Brain Barrier / enzymology*
  • Blotting, Western
  • Brain Edema / pathology
  • Brain Ischemia / enzymology*
  • Brain Ischemia / pathology*
  • Claudin-5
  • Immunohistochemistry
  • Infarction, Middle Cerebral Artery / pathology
  • Interleukin-6 / biosynthesis
  • Ligation
  • Male
  • Matrix Metalloproteinase 2 / biosynthesis
  • Matrix Metalloproteinase 9 / biosynthesis
  • Matrix Metalloproteinases / biosynthesis*
  • Membrane Proteins / biosynthesis
  • Middle Cerebral Artery / pathology
  • Occludin
  • Permeability
  • Pregnanolone / pharmacology*
  • Progesterone / pharmacology*
  • Rats
  • Rats, Sprague-Dawley
  • Stroke / drug therapy
  • Stroke / pathology
  • Tumor Necrosis Factor-alpha / biosynthesis


  • Claudin-5
  • Cldn5 protein, rat
  • Interleukin-6
  • Membrane Proteins
  • Occludin
  • Ocln protein, rat
  • Tumor Necrosis Factor-alpha
  • Progesterone
  • Pregnanolone
  • Matrix Metalloproteinases
  • Matrix Metalloproteinase 2
  • Matrix Metalloproteinase 9