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Jiang Z, Watts LT, Huang S, Shen Q, Rodriguez P, Chen C, Zhou C, Duong TQ. The Effects of Methylene Blue on Autophagy and Apoptosis in MRI-Defined Normal Tissue, Ischemic Penumbra and Ischemic Core. PLoS One 2015; 10:e0131929. [PMID: 26121129 PMCID: PMC4488003 DOI: 10.1371/journal.pone.0131929] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2014] [Accepted: 06/09/2015] [Indexed: 12/11/2022] Open
Abstract
Methylene blue (MB) USP, which has energy-enhancing and antioxidant properties, is currently used to treat methemoglobinemia and cyanide poisoning in humans. We recently showed that MB administration reduces infarct volume and behavioral deficits in rat models of ischemic stroke and traumatic brain injury. This study reports the underlying molecular mechanisms of MB neuroprotection following transient ischemic stroke in rats. Rats were subjected to transient (60-mins) ischemic stroke. Multimodal MRI during the acute phase and at 24 hrs were used to define three regions of interest (ROIs): i) the perfusion-diffusion mismatch salvaged by reperfusion, ii) the perfusion-diffusion mismatch not salvaged by reperfusion, and iii) the ischemic core. The tissues from these ROIs were extracted for western blot analyses of autophagic and apoptotic markers. The major findings were: 1) MB treatment reduced infarct volume and behavioral deficits, 2) MB improved cerebral blood flow to the perfusion-diffusion mismatch tissue after reperfusion and minimized harmful hyperperfusion 24 hrs after stroke, 3) MB inhibited apoptosis and enhanced autophagy in the perfusion-diffusion mismatch, 4) MB inhibited apoptotic signaling cascades (p53-Bax-Bcl2-Caspase3), and 5) MB enhanced autophagic signaling cascades (p53-AMPK-TSC2-mTOR). MB induced neuroprotection, at least in part, by enhancing autophagy and reducing apoptosis in the perfusion-diffusion mismatch tissue following ischemic stroke.
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Affiliation(s)
- Zhao Jiang
- Department of Anatomy and Embryology, Peking University Health Science Center, Beijing, China
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Lora Talley Watts
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Shiliang Huang
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Qiang Shen
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Pavel Rodriguez
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Chunhua Chen
- Department of Anatomy and Embryology, Peking University Health Science Center, Beijing, China
- Department of Anesthesiology and Critical Care, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America
| | - Changman Zhou
- Department of Anatomy and Embryology, Peking University Health Science Center, Beijing, China
| | - Timothy Q. Duong
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
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Cardiac Arrest Alters Regional Ubiquitin Levels in Association with the Blood–Brain Barrier Breakdown and Neuronal Damages in the Porcine Brain. Mol Neurobiol 2015; 52:1043-53. [DOI: 10.1007/s12035-015-9254-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2015] [Indexed: 01/06/2023]
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53
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Skendelas JP, Muccigrosso M, Eiferman DS, Godbout JP. Chronic Inflammation After TBI and Associated Behavioral Sequelae. CURRENT PHYSICAL MEDICINE AND REHABILITATION REPORTS 2015. [DOI: 10.1007/s40141-015-0091-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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54
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Talley Watts L, Shen Q, Deng S, Chemello J, Duong TQ. Manganese-Enhanced Magnetic Resonance Imaging of Traumatic Brain Injury. J Neurotrauma 2015; 32:1001-10. [PMID: 25531419 DOI: 10.1089/neu.2014.3737] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Calcium dysfunction is involved in secondary traumatic brain injury (TBI). Manganese-enhanced MRI (MEMRI), in which the manganese ion acts as a calcium analog and a MRI contrast agent, was used to study rats subjected to a controlled cortical impact. Comparisons were made with conventional T2 MRI, sensorimotor behavior, and immunohistology. The major findings were: (1) Low-dose manganese (29 mg/kg) yielded excellent contrast with no negative effects on behavior scores relative to vehicle; (2) T1-weighted MEMRI was hyperintense in the impact area at 1-3 h, hypointense on day 2, and markedly hypointense with a hyperintense area surrounding the core on days 7 and/or 14, in contrast to the vehicle group, which did not show a biphasic profile; (3) in the hyperacute phase, the area of hyperintense T1-weighted MEMRI was larger than that of T2 MRI; (4) glial fibrillary acidic protein staining revealed that the MEMRI signal void in the impact core and the hyperintense area surrounding the core on day 7 and/or 14 corresponded to tissue cavitation and reactive gliosis, respectively; (5) T2 MRI showed little contrast in the impact core at 2 h, hyperintense on day 2 (indicative of vasogenic edema), hyperintense in some animals but pseudonormalized in others on day 7 and/or 14; (6) behavioral deficit peaked on day 2. We concluded that MEMRI detected early excitotoxic injury in the hyperacute phase, preceding vasogenic edema. In the subacute phase, MEMRI detected contrast consistent with tissue cavitation and reactive gliosis. MEMRI offers novel contrasts of biological processes that complement conventional MRI in TBI.
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Affiliation(s)
- Lora Talley Watts
- 1 Research Imaging Institute, University of Texas Health Science Center , San Antonio, Texas.,2 Department of Cellular and Structure Biology, University of Texas Health Science Center , San Antonio, Texas.,3 Department of Neurology, University of Texas Health Science Center , San Antonio, Texas
| | - Qiang Shen
- 1 Research Imaging Institute, University of Texas Health Science Center , San Antonio, Texas.,4 Department of Ophthalmology, University of Texas Health Science Center , San Antonio, Texas
| | - Shengwen Deng
- 1 Research Imaging Institute, University of Texas Health Science Center , San Antonio, Texas
| | - Jonathan Chemello
- 1 Research Imaging Institute, University of Texas Health Science Center , San Antonio, Texas
| | - Timothy Q Duong
- 1 Research Imaging Institute, University of Texas Health Science Center , San Antonio, Texas.,4 Department of Ophthalmology, University of Texas Health Science Center , San Antonio, Texas.,5 South Texas Veterans Health Care System , San Antonio, Texas
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55
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Methylene blue protects astrocytes against glucose oxygen deprivation by improving cellular respiration. PLoS One 2015; 10:e0123096. [PMID: 25848957 PMCID: PMC4388695 DOI: 10.1371/journal.pone.0123096] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2014] [Accepted: 02/27/2015] [Indexed: 11/19/2022] Open
Abstract
Astrocytes outnumber neurons and serve many metabolic and trophic functions in the mammalian brain. Preserving astrocytes is critical for normal brain function as well as for protecting the brain against various insults. Our previous studies have indicated that methylene blue (MB) functions as an alternative electron carrier and enhances brain metabolism. In addition, MB has been shown to be protective against neurodegeneration and brain injury. In the current study, we investigated the protective role of MB in astrocytes. Cell viability assays showed that MB treatment significantly protected primary astrocytes from oxygen-glucose deprivation (OGD) & reoxygenation induced cell death. We also studied the effect of MB on cellular oxygen and glucose metabolism in primary astrocytes following OGD-reoxygenation injury. MB treatment significantly increased cellular oxygen consumption, glucose uptake and ATP production in primary astrocytes. In conclusion our study demonstrated that MB protects astrocytes against OGD-reoxygenation injury by improving astrocyte cellular respiration.
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56
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Abstract
Effective traumatic brain injury (TBI) therapeutics remains stubbornly elusive. Efforts in the field have been challenged by the heterogeneity of clinical TBI, with greater complexity among underlying molecular phenotypes than initially conceived. Future research must confront the multitude of factors comprising this heterogeneity, representing a big data challenge befitting the coming informatics age. Proteomics is poised to serve a central role in prescriptive therapeutic development because it offers an efficient endpoint within which to assess post-TBI biochemistry. We examine rationale for multifactor TBI proteomic studies and the particular importance of temporal profiling in defining biochemical sequences and guiding therapeutic development. Finally, we offer perspective on repurposing biofluid proteomics to develop theragnostic assays with which to prescribe, monitor and assess pharmaceutics for improved translation and outcome for patients with TBI.
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Affiliation(s)
- Pavel N. Lizhnyak
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, USA
| | - Andrew K. Ottens
- Department of Anatomy and Neurobiology, Virginia Commonwealth University School of Medicine, Richmond, VA 23298, USA
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57
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Long JA, Watts LT, Chemello J, Huang S, Shen Q, Duong TQ. Multiparametric and longitudinal MRI characterization of mild traumatic brain injury in rats. J Neurotrauma 2015; 32:598-607. [PMID: 25203249 DOI: 10.1089/neu.2014.3563] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
This study reports T2 and diffusion-tensor magnetic resonance imaging (MRI) studies of a mild open-skull, controlled cortical impact injury in rats (n=6) from 3 h to up to 14 d after traumatic brain injury (TBI). Comparison was made with longitudinal behavioral measurements and end-point histology. The impact was applied over the left primary forelimb somatosensory cortex (S1FL). The major findings were: 1) In the S1FL, T2 increased and fractional anisotropy (FA) decreased at 3 h after TBI and gradually returned toward normal by Day 14; 2) in the S1FL, the apparent diffusion coefficient (ADC) increased at 3 h, peaked on Day 2, and gradually returned toward normal at Day 14; 3) in the corpus callosum underneath the S1FL, FA decreased at 3 h to Day 2 but returned to normal at Day 7 and 14, whereas T2 and ADC were normal throughout; 4) heterogeneous hyperintense and hypointense T2 map intensities likely indicated the presence of hemorrhage but were not independently verified; 5) lesion volumes defined by abnormal T2, ADC, and FA showed similar temporal patterns, peaking around Day 2 and returning toward normal on Day 14; 6) the temporal profiles of lesion volumes were consistent with behavioral scores assessed by forelimb placement and forelimb foot fault tests; and 7) at 14 d post-TBI, there was substantial tissue recovery by MRI, which could either reflect true tissue recovery or reabsorption of edema. Histology performed 14 d post-TBI, however, showed a small cavitation and significant neuronal degeneration surrounding the cavitation in S1FL. Thus, the observed improvement of behavioral scores likely involves both functional recovery and functional compensation.
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Affiliation(s)
- Justin Alexander Long
- 1 Research Imaging Institute, University of Texas Health Science Center at San Antonio , San Antonio, Texas
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58
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Prasad KN, Bondy SC. Common biochemical defects linkage between post-traumatic stress disorders, mild traumatic brain injury (TBI) and penetrating TBI. Brain Res 2014; 1599:103-14. [PMID: 25553619 DOI: 10.1016/j.brainres.2014.12.038] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 12/18/2014] [Accepted: 12/19/2014] [Indexed: 12/29/2022]
Abstract
Post-traumatic stress disorder (PTSD) is a complex mental disorder with psychological and emotional components, caused by exposure to single or repeated extreme traumatic events found in war, terrorist attacks, natural or man-caused disasters, and by violent personal assaults and accidents. Mild traumatic brain injury (TBI) occurs when the brain is violently rocked back and forth within the skull following a blow to the head or neck as in contact sports, or when in close proximity to a blast pressure wave following detonation of explosives in the battlefield. Penetrating TBI occurs when an object penetrates the skull and damages the brain, and is caused by vehicle crashes, gunshot wound to the head, and exposure to solid fragments in the proximity of explosions, and other combat-related head injuries. Despite clinical studies and improved understanding of the mechanisms of cellular damage, prevention and treatment strategies for patients with PTSD and TBI remain unsatisfactory. To develop an improved plan for treating and impeding progression of PTSD and TBI, it is important to identify underlying biochemical changes that may play key role in the initiation and progression of these disorders. This review identifies three common biochemical events, namely oxidative stress, chronic inflammation and excitotoxicity that participate in the initiation and progression of these conditions. While these features are separately discussed, in many instances, they overlap. This review also addresses the goal of developing novel treatments and drug regimens, aimed at combating this triad of events common to, and underlying, injury to the brain.
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Affiliation(s)
- Kedar N Prasad
- Antioxidant Research Institute, Premier Micronutrient Corporation, 14 Galli Drive, suite 200, Novato, CA 94949, USA.
| | - Stephen C Bondy
- Center for Occupational and Environmental Health, Department of Medicine, University of California, Irvine, CA 92697-1830, USA.
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Li W, Long JA, Watts LT, Jiang Z, Shen Q, Li Y, Duong TQ. A quantitative MRI method for imaging blood-brain barrier leakage in experimental traumatic brain injury. PLoS One 2014; 9:e114173. [PMID: 25478693 PMCID: PMC4257611 DOI: 10.1371/journal.pone.0114173] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2014] [Accepted: 11/04/2014] [Indexed: 01/21/2023] Open
Abstract
Blood-brain barrier (BBB) disruption is common following traumatic brain injury (TBI). Dynamic contrast enhanced (DCE) MRI can longitudinally measure the transport coefficient Ktrans which reflects BBB permeability. Ktrans measurements however are not widely used in TBI research because it is generally considered to be noisy and possesses low spatial resolution. We improved spatiotemporal resolution and signal sensitivity of Ktrans MRI in rats by using a high-sensitivity surface transceiver coil. To overcome the signal drop off profile of the surface coil, a pre-scan module was used to map the flip angle (B1 field) and magnetization (M0) distributions. A series of T1-weighted gradient echo images were acquired and fitted to the extended Kety model with reversible or irreversible leakage, and the best model was selected using F-statistics. We applied this method to study the rat brain one hour following controlled cortical impact (mild to moderate TBI), and observed clear depiction of the BBB damage around the impact regions, which matched that outlined by Evans Blue extravasation. Unlike the relatively uniform T2 contrast showing cerebral edema, Ktrans shows a pronounced heterogeneous spatial profile in and around the impact regions, displaying a nonlinear relationship with T2. This improved Ktrans MRI method is also compatible with the use of high-sensitivity surface coil and the high-contrast two-coil arterial spin-labeling method for cerebral blood flow measurement, enabling more comprehensive investigation of the pathophysiology in TBI.
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Affiliation(s)
- Wei Li
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- Department of Ophthalmology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- * E-mail: (WL); (TQD)
| | - Justin Alexander Long
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Lora Talley Watts
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- Department of Cellular and Structure Biology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- Department of Neurology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Zhao Jiang
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Qiang Shen
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Yunxia Li
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
| | - Timothy Q. Duong
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- Department of Ophthalmology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- Department of Neurology, University of Texas Health Science Center at San Antonio, San Antonio, Texas, United States of America
- South Texas Veterans Health Care System, Department of Veterans Affairs, San Antonio, Texas, United States of America
- * E-mail: (WL); (TQD)
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60
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Fenn AM, Skendelas JP, Moussa DN, Muccigrosso MM, Popovich PG, Lifshitz J, Eiferman DS, Godbout JP. Methylene blue attenuates traumatic brain injury-associated neuroinflammation and acute depressive-like behavior in mice. J Neurotrauma 2014; 32:127-38. [PMID: 25070744 DOI: 10.1089/neu.2014.3514] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Traumatic brain injury (TBI) is associated with cerebral edema, blood brain barrier breakdown, and neuroinflammation that contribute to the degree of injury severity and functional recovery. Unfortunately, there are no effective proactive treatments for limiting immediate or long-term consequences of TBI. Therefore, the objective of this study was to determine the efficacy of methylene blue (MB), an antioxidant agent, in reducing inflammation and behavioral complications associated with a diffuse brain injury. Here we show that immediate MB infusion (intravenous; 15-30 minutes after TBI) reduced cerebral edema, attenuated microglial activation and reduced neuroinflammation, and improved behavioral recovery after midline fluid percussion injury in mice. Specifically, TBI-associated edema and inflammatory gene expression in the hippocampus were significantly reduced by MB at 1 d post injury. Moreover, MB intervention attenuated TBI-induced inflammatory gene expression (interleukin [IL]-1β, tumor necrosis factor α) in enriched microglia/macrophages 1 d post injury. Cell culture experiments with lipopolysaccharide-activated BV2 microglia confirmed that MB treatment directly reduced IL-1β and increased IL-10 messenger ribonucleic acid in microglia. Last, functional recovery and depressive-like behavior were assessed up to one week after TBI. MB intervention did not prevent TBI-induced reductions in body weight or motor coordination 1-7 d post injury. Nonetheless, MB attenuated the development of acute depressive-like behavior at 7 d post injury. Taken together, immediate intervention with MB was effective in reducing neuroinflammation and improving behavioral recovery after diffuse brain injury. Thus, MB intervention may reduce life-threatening complications of TBI, including edema and neuroinflammation, and protect against the development of neuropsychiatric complications.
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Affiliation(s)
- Ashley M Fenn
- 1 Department of Neuroscience, Ohio State University , Columbus, Ohio
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61
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The antioxidative, non-psychoactive tricyclic phenothiazine reduces brain damage after experimental traumatic brain injury in mice. Neurosci Lett 2014; 584:253-8. [PMID: 25449871 DOI: 10.1016/j.neulet.2014.10.037] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Revised: 10/16/2014] [Accepted: 10/20/2014] [Indexed: 12/23/2022]
Abstract
Oxidative stress due to free radical formation is an important mechanism of secondary brain damage following traumatic brain injury (TBI). Phenothiazine has been found to be a strong antioxidant in eukaryotic cells in vitro and in invertebrates in vivo. The present study was designed to determine the neuroprotective potency of unsubstituted phenothiazine in a paradigm of acute brain injury. Thirty minutes after pneumatic, controlled cortical impact (CCI) injury, C57BI6 mice were randomly assigned to "low dose" (3 mg/kg, LD) or "high dose" (30 mg/kg, HD) s.c. phenothiazine or vehicle treatment. Brain lesion, neurofunctional impairment, body weight, and markers of cerebral inflammation were determined 24h after the insult. Phenothiazine treatment dose-dependently reduced brain lesion volume (LD: -19.8%; HD: -26.1%) and posttraumatic body weight loss. There were no significant differences in the neurological function score and in markers of cerebral inflammation (Iba-1 positive cells, TNFα expression), whereas iNOS expression was significantly lower compared to vehicle-treated animals. Phenothiazine appears to modify in a post-treatment protocol certain aspects of secondary brain damage in vivo at unusually low concentrations, in particular the cortical contusion volume after TBI. The potential role of the reduced iNOS expression is unclear at present.
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62
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Rodriguez P, Jiang Z, Huang S, Shen Q, Duong TQ. Methylene blue treatment delays progression of perfusion-diffusion mismatch to infarct in permanent ischemic stroke. Brain Res 2014; 1588:144-9. [PMID: 25218555 DOI: 10.1016/j.brainres.2014.09.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Revised: 07/12/2014] [Accepted: 09/02/2014] [Indexed: 11/29/2022]
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.
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Affiliation(s)
- Pavel Rodriguez
- Research Imaging Institute, Radiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Zhao Jiang
- 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
| | - Shiliang Huang
- Research Imaging Institute, Radiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Qiang Shen
- Research Imaging Institute, Radiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States
| | - Timothy Q Duong
- Research Imaging Institute, Radiology, University of Texas Health Science Center at San Antonio, San Antonio, TX, United States.
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