The lesions also include severe alterations to the blood–brain barrier (BBB), which increase its permeability to several substances including blood components and exogenous fluorescent dyes, and the concomitant degradation of some of its constituents such as endothelial cells, tight junction proteins and the basement membrane. We studied here the role of matrix metalloproteinases (MMPs)-2 and -9, also called gelatinases A and B, in the degradation of the BBB in the striatal lesions induced by the
systemic administration of 3-NPA to Sprague-Dawley rats. Methods: 3-NPA was intraperitoneally EPZ6438 administered at a dose of 20 mg/kg once a day for 3 days. MMPs were studied by means of immunohistochemistry and in situ zymography. Results: In 3-NPA-treated rats, MMP-9 was present in most of the degraded blood vessels in the injured striatum, while it was absent in vessels from non-injured tissue. In the same animals, MMP-2 staining was barely detected close to degraded blood vessels. The combination of MMP-9 immunostaining, in situ zymography and inhibitory
studies of MMP-9 confirmed that net gelatinolytic activity detected in the degraded striatal blood vessels could be attributed almost exclusively to the active form of MMP-9. Conclusion: Our results highlight the prominent role of MMP-9 in BBB disruption Selleckchem Tamoxifen in the striatal injured areas of this experimental model of Huntington’s disease. “
“Whether or not the oral intake
of metals such as aluminium (Al) and zinc (Zn) is a risk for Alzheimer’s disease (AD) has been a matter of controversy. Lack of AD pathology in patients with Al encephalopathy indicates Al does not cause AD. On the other hand, some epidemiological studies have suggested high Al increases the occurrence of AD. Our purpose is to test very if high Al in drinking water is a risk factor for AD. We administered Al and Zn in drinking water to Tg2576, a transgenic mouse model for amyloid β-protein (Aβ) deposition with the Aβ precursor protein (AβPP) mutations (K670N/M671L), and Tg2576/tau(P301L), a model for Aβ and tau deposition. Deionized water was given to the control Tg2576 and Tg2576/tau. After administration for 4–10 months of approximately 100 mg/kg body weight Al or Zn per day, we were not able to find by quantitative immunohistochemical analyses differences in the deposition of Aβ and tau between the treated and untreated groups. Nor did the Al or Zn treatment affect the amount of soluble Aβ and Aβ*56, an Aβ oligomer, measured by ELISA or immunoblot. The oral intake of excess Al or Zn does not accelerate AD pathology in the transgenic mouse models for Aβ and tau accumulation. Such results do not seem to support the notion that excessive oral intake of Al or Zn is a risk factor for AD.