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ARS Home » Plains Area » Grand Forks, North Dakota » Grand Forks Human Nutrition Research Center » Healthy Body Weight Research » Research » Publications at this Location » Publication #199734
Title: Copper deficiency decreases the protein expression of Complex IV but not Complex I, II, III, or V in mitochondrial respiratory chain in rat heart

Author
item Zeng, Huawei
item Saari, Jack
item Johnson, William

Submitted to: Journal of Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/17/2006
Publication Date: 1/1/2007
Citation: Zeng, H., Saari, J.T., Johnson, W.T. 2007. Copper deficiency decreases complex IV but not complex I, II, III, or V in the mitochondrial respiratory chain in rat heart. Journal of Nutrition. 137:14-18.

Interpretive Summary: Dietary copper (Cu) deficiency has been implicated in a number of conditions including cardiomyopathy, impaired immune function and higher cancer risk. It has been documented that dietary copper deficiency impairs mitochondrial respiratory function. The present study was undertaken to determine the effect of Cu deficiency on each OxPhos complex’s protein expression in rat heart tissue with Western blot analysis. Our data demonstrate that copper deficiency decreases the every tested subunit protein expression of complex IV but not those of complex I, II, III and V in oxidative phosphorylation chain. These data provide new insights into the regulation of protein expression related to mitochondrial respiratory function of the Cu-deficient rat heart. These findings will be useful information for scientists and health-care people who are interested in nutritional copper and cardiovascular health.

Technical Abstract: It has been documented that dietary copper (Cu) deficiency impairs mitochondrial respiratory function which is catalyzed by five membrane-bound multiple protein complexes. However, there are few reports on the simultaneous analysis of Cu effect on the subunit protein expression on all five protein complexes. The present study was undertaken to determine the effect of Cu deficiency on each OxPhos complex’s protein expression in rat heart tissue with Western blot analysis. Male Sprague-Dawley rats were fed diets that were either Cu-adequate (6.0 micro g Cu/g diet n = 5) or Cu-deficient (0.3 micro g Cu/g diet n = 5) for 5 wk. The monoclonal antibody-based Western blot analysis suggested that the protein levels of 39 kDa and 30 kDa subunits in complex I; 70 kDa and 30 kDa subunits in complex II; core I and core II subunits in complex III; alpha and beta subunits of F1 complex in complex V in both high-salt buffer (HSB) and low-salt buffer (LSB) protein fractions from heart tissue of Cu-deficient rats did not differ from those of Cu-adequate rats. However, the protein level of COX I, COX Vb and COX VIb subunits in complex IV in both high-salt buffer (HSB) and low-salt buffer (LSB) protein fractions from heart tissue of Cu-deficient rats was lower than those of Cu-adequate rats. Collectively, these data demonstrate that copper deficiency decreases each tested subunit protein expression of complex IV but not those of complex I, II, III and V in oxidative phosphorylation chain.