3D imaging of the mitochondrial redox state of rathearts under normal and fasting conditions  

作　　者：He N.Xu Rong Zhou Lily Moon Min Feng Lin Z.Li 

机构地区：[1]Department of Radiology Universityof PennsyluaniaPhilade lphia,PA 19104,USA [2]Briton Chance Laboratory of Redor Imaging Johnson Research Foundation,Department of Biochemistry and Biophysics University of Pennsyluania Philade lphia,PA 19104,USA [3]Institute of Translational Medicine and Therapeutics Perelman School of Medicine University of Pennsylvania Philadelphia,PA 19104,USA

出　　处：《Journal of Innovative Optical Health Sciences》2014年第2期60-69,共10页创新光学健康科学杂志（英文）

基　　金：supported by the Center of Magnetic Resonance and Optical Imaging(CMROn)--an NIH supported research resource P41RR02305(R.Reddy)。

摘　　要：The heart requires continuous ATP availability that is generated in the mitochondria.Althoughstudies using the cell culture and perfiused organ models have been carried out to investigate thebiochemistry in the mitochondria in response to a change in substrate supply,mitochondrialbioenergetics of heart under normal feed or fasting conditions has not been studied at the tissuelevel with a sub-millimeter spatial resolution either in vivo or er vivo.Oxidation of many food-derived metabolites to generate ATP in the mitochondria is realized through the NADH/NAD+couple acting as a central electron carrier.We employed the Chance redox scanner thelow-temperat ure fluorescence scanner to image the three-dimensional(3D)spatial distribution of themitochondrial redox states in heart tissues of rats under normai feeding or an overnight star-vation for 14.5 h.Multiple consecutive sections of each heart were imaged to map three redoxindices,i.e,NADH,oxidized favoproteins Fp,including flavin adenine dinucleotide(FAD)andthe redox ratio NADH/Fp.The imaging results revealed the micro-heterogeneity and the spatial distribution of these redox indices.The quantitative analysis showed that in the fasted hearts thestandard deviation of both NADH and Fp,ie.,SD NADH and SDFp,significantly decreasedwith a p value of 0.032 and 0.045,respectively,indicating that the hearts become relatively morehomogeneous after fasting.The fasted hearts contained 28.6%less NADH(p=0.038).No sig.nificant change in Fp was foumnd(p=0.4).The NADH/Fp ratio decreased with a marginalP value(0.076).The decreased NADH im the fasted hearts is consistent with the cardiac celsreliance of fatty acids consumption for energy metabolism when glucose becomes scarce.Theexperimental o bservation of N ADH decrease induced by dietary restriction in the heart at tissuelevel has not been reported to our best knowledge.The Chance redox scanner demonstrated thefeasibility of 3D imaging of the mitochondrial redox st ate in the heart and provides a usefil toolto study heart metabolism

关 键 词：Mitochondion metabolism BIOENERGETICS CARDIOMYOCYTE NADH FLAVOPROTEINS Fp FAD caloric restriction food deprivation. 

分 类 号：R54[医药卫生—心血管疾病]