کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
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2200919 | 1099986 | 2011 | 8 صفحه PDF | دانلود رایگان |

Oxidative stress may be involved in the dopaminergic neurodegenerations seen in 6-OHDA-lesioned rats through its production of free radicals and through mitochondrial dysfunction. In this study, we noninvasively demonstrate brain redox alterations in 6-OHDA-lesioned rats using Overhauser-enhanced magnetic resonance imaging (OMRI). The reduction rate of 3-methoxycarbonyl-2,2,5,5-tetramethylpyrrolidine-l-oxyl (methoxycarbonyl-PROXYL), a redox-sensitive contrast agent, was used as an index of the redox status in vivo. The methoxycarbonyl-PROXYL reduction rate, calculated from continuous images, decreased significantly in lesioned hemispheres compared to their corresponding contralateral hemispheres. The reduction rates in cellular fractions obtained from the striatum were estimated by X-band electron spin resonance (ESR) and calculated by assuming first-order kinetics for their time-dependent decreases. When methoxycarbonyl-PROXYL was mixed with cytoplasm fractions, the reduction rates were the same in both hemispheres. However, the ESR signal of methoxycarbonyl-PROXYL in the mitochondrial fraction of the lesioned hemispheres decayed more slowly than that of the corresponding contralateral hemispheres. Concordantly, biochemical assays showed that the activity of mitochondrial complex I also decreased more slowly in lesioned hemispheres. Thus, this method of noninvasively imaging brain redox alterations faithfully reflects changes in mitochondrial complex I activity in 6-OHDA-lesioned rats.
► Using OMRI, we noninvasively demonstrated that brain redox alterations occur in 6-OHDA-lesioned rats.
► Redox alterations were reflected in changes in mitochondrial complex I activity.
► Redox imaging may be useful for noninvasively evaluating the progress of Parkinson’s disease.
Journal: Neurochemistry International - Volume 59, Issue 6, November 2011, Pages 804–811