کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9881328 1535698 2005 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Defects in activation of nitric oxide synthases occur during delayed angiogenesis in aging
موضوعات مرتبط
علوم زیستی و بیوفناوری بیوشیمی، ژنتیک و زیست شناسی مولکولی سالمندی
پیش نمایش صفحه اول مقاله
Defects in activation of nitric oxide synthases occur during delayed angiogenesis in aging
چکیده انگلیسی
Angiogenesis, the formation of new vessels from pre-existing vasculature, is impaired in aging. This is due, in part, to a lack of regulatory molecules such as nitric oxide (NO). We wished to test the hypothesis that there are deficits in the pathways that mediate NO production during angiogenesis (as defined by fibrovascular invasion into a polyvinyl alcohol (PVA) sponge implant), in aged mice in comparison to young mice. Sponges were implanted subcutaneously in young (6-8 months old, n = 11) and aged (23-25 months old, n = 13) mice and sampled at 14 and 19 days. Sections from the implants were stained with antibodies against vascular endothelial growth factor receptor 2 (VEGFR-2), Akt, phosphorylated Akt (p-Akt), endothelial nitric oxide synthase (eNOS), phosphorylated eNOS (p-eNOS), inducible NOS (iNOS), and 3-nitrotyrosine (3-NT, a marker for nitrosylated proteins). Expression of VEGFR-2 was similar in the sponges of young and aged mice. Moreover, there were no significant differences in levels of Akt or its phosphorylated form in sponges from young and aged mice at 14 and 19 d. In marked contrast, levels of eNOS, p-eNOS and iNOS were significantly decreased in sponges from aged mice relative to young mice (p < 0.02 for eNOS, p-eNOS and < 0.01 for iNOS between young and aged mice). Concomitantly, there was diminished expression of 3-NT in the sponges from aged mice (p < 0.05). Our data indicate that defects in the activation of nitric oxide synthases result in decreased NO production in aged tissues relative to young tissues. We propose that the subsequent lack of NO contributes to impaired angiogenesis in aging.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Mechanisms of Ageing and Development - Volume 126, Issue 4, April 2005, Pages 467-473
نویسندگان
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