title: Methylene blue treatment delays progression of perfusion-diffusion mismatch to infarct in permanent ischemic stroke.
abstract: Stroke is a leading cause of morbidity and mortality in the world. Low-dose methylene blue (MB), which has been used safely to treat methemoglobinemia and cyanide poisoning in humans, has energy enhancing and antioxidant properties. We tested the hypothesis that methylene blue treatment delays progression of at-risk tissue (ca. perfusion-diffusion mismatch) to infarct in permanent middle cerebral artery occlusion in rats at two MB treatment doses. Serial MRI was used to evaluate MB treatment efficacy. The major findings were: (i) MB significantly prolonged the perfusion-diffusion mismatch, (ii) MB mildly increased the CBF in the hypoperfused tissue, (iii) MB did not change the final infarct volume in permanent ischemic stroke, and (iv) there were no dose-dependent effects on mismatch progression for the 1 and 3mg/kg doses studied. This neuroprotective effect is likely the result of sustained ATP production and increased CBF to tissue at risk. This work has the potential to readily lead to clinical stroke trials given MB's excellent safety profile.
authors.affiliation: Research Imaging Institute, Radiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States.
authors.forename: Pavel
authors.initials: P
authors.lastname: Rodriguez
authors.affiliation: Research Imaging Institute, Radiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States; Department of Anatomy and Embryology, Peking University Health Science Center, Beijing, China.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Jiang
authors.affiliation: Research Imaging Institute, Radiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States.
authors.forename: Shiliang
authors.initials: S
authors.lastname: Huang
authors.affiliation: Research Imaging Institute, Radiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Shen
authors.affiliation: Research Imaging Institute, Radiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States. Electronic address: DuongT@uthscsa.edu.
authors.forename: Timothy Q
authors.initials: TQ
authors.lastname: Duong
mesh_terms: D000818:Animals; D001921:Brain / Q000187:drug effects / Q000473:pathology / Q000503:physiopathology; D002545:Brain Ischemia / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D002560:Cerebrovascular Circulation / Q000187:drug effects / Q000502:physiology; D004195:Disease Models, Animal; D018450:Disease Progression; D004305:Dose-Response Relationship, Drug; D020244:Infarction, Middle Cerebral Artery; D008279:Magnetic Resonance Imaging; D008297:Male; D008751:Methylene Blue / Q000627:therapeutic use*; D018696:Neuroprotective Agents / Q000627:therapeutic use*; D011897:Random Allocation; D017207:Rats, Sprague-Dawley; D016896:Treatment Outcome
chemical_list: D018696:Neuroprotective Agents; D008751:Methylene Blue
keywords: Infarct volume; Ischemic penumbra; MRI; Middle-cerebral artery occlusion; Neuroprotection; Oxidative stress