Cytochrome c oxidase is regulated by modulations in protein expression and mitochondrial membrane phospholipid composition in estivating African lungfish

2010 ◽  
Vol 298 (3) ◽  
pp. R608-R616 ◽  
Author(s):  
N. T. Frick ◽  
J. S. Bystriansky ◽  
Y. K. Ip ◽  
S. F. Chew ◽  
J. S. Ballantyne
Keyword(s):  
Cytochrome C ◽  
Protein Expression ◽  
Cytochrome C Oxidase ◽  
Mitochondrial Membrane ◽  
Translational Regulation ◽  
Phospholipid Composition ◽  
Liver Mitochondria ◽  
Membrane Phospholipids ◽  
Tissue Specific ◽  
African Lungfish

We examined some of the potential mechanisms lungfish ( Protopterus dolloi ) use to regulate cytochrome c oxidase (CCO), during metabolic depression. CCO activity was reduced by 67% in isolated liver mitochondria of estivating fish. This was likely accomplished, in part, by the 46% reduction in CCO subunit I protein expression in the liver. No change in the mRNA expression levels of CCO subunits I, II, III, and IV were found in the liver, suggesting CCO is under translational regulation; however, in the kidney, messenger limitation may be a factor as the expression of subunits I and II were depressed (∼10-fold) during estivation, suggesting tissue-specific mechanisms of regulation. CCO is influenced by mitochondrial membrane phospholipids, particularly cardiolipin (CL). In P. dolloi , the phospholipid composition of the liver mitochondrial membrane changed during estivation, with a ∼2.3-fold reduction in the amount of CL. Significant positive correlations were found between CCO activity and the amount of CL and phosphatidylethanolamine within the mitochondrial membrane. It appears CCO activity is regulated through multiple mechanisms in P. dolloi , and individual subunits of CCO are regulated independently, and in a tissue-specific manner. It is proposed that altering the amount of CL within the mitochondrial membrane may be a means of regulating CCO activity during metabolical depression in the African lungfish, P. dolloi .

Tissue-Specific Expression of Cytochrome c Oxidase Isoforms and Role in Nonshivering Thermogenesis

1999 ◽  
pp. 621-633
Author(s):  
Bernhard Kadenbach ◽  
Viola Frank ◽  
Dietmar Linder ◽  
Susanne Arnold ◽  
Stefan Exner ◽  
...  
Keyword(s):  
Cytochrome C ◽  
Cytochrome C Oxidase ◽  
Nonshivering Thermogenesis ◽  
Specific Expression ◽  
Tissue Specific ◽  
Tissue Specific Expression

scholarly journals A Comprehensive Review of the Cosmeceutical Benefits of Vanda Species (Orchidaceae)

2015 ◽  
Vol 10 (8) ◽  
pp. 1934578X1501000 ◽  
Author(s):  
Hazrina Hadi ◽  
Syarifah Nazira Said Razali ◽  
Ammar Ihsan Awadh
Keyword(s):  
Cytochrome C ◽  
Protein Expression ◽  
Cytochrome C Oxidase ◽  
Binding Capacity ◽  
Active Agent ◽  
Fold Increase ◽  
Skin Hydration ◽  
Water Evaporation ◽  
Structural Function ◽  
Water Binding

Orchidaceae is the largest family of flowering plants with over 35000 species and 850 genera. About 3300 species of orchids are found in Malaysia and the diversity is highest in the Main, Keledang, Bintang and Tahan Ranges. Apart from being prized for their beauty, orchids have long been used by humans for medicinal purposes. Today the uses of orchids have been expanded to the food and cosmetics industries. Many cosmeceutical companies use orchid extracts as an active ingredient in their products. Previous studies provide riveting insights into the potential uses of orchid extracts as an active agent in cosmetics. This paper describes the cosmeceutical potential of orchids as an anti-aging, and skin moisturizing agent. Orchid extracts from Vanda coerulea and V. teres delay aging caused by reactive oxygen species (ROS) following UV irradiation through their antioxidant and anti-inflammatory activity. These extracts also show anti-aging properties by stimulating cytochrome c oxidase (complex IV), which is part of the electron transport chain in mitochondria. Stimulation of cytochrome c oxidase improves the respiratory function of mitochondria in keratinocytes. The presence of mucilage in orchids enables them to maintain skin hydration. Mucilage functions as a moisturizer and emollient due to its high water binding capacity. Additionally, orchid extracts provide skin hydration by stimulating aquaporin 3 (AQP3) and LEKTI protein expression. The presence of AQP3 leads to a five-fold increase in water permeability, which subsequently increases stratum corneum hydration. Increased LEKTI protein expression mediated by orchid extracts reduces the degradation of desmoglein-1 and enhances the structural function of desmosomes, which play important roles in preventing water evaporation.

scholarly journals Cytochrome c oxidase III as a mechanism for apoptosis in heart failure following myocardial infarction

2009 ◽  
Vol 297 (4) ◽  
pp. C928-C934 ◽  
Author(s):  
Changgong Wu ◽  
Lin Yan ◽  
Christophe Depre ◽  
Sunil K. Dhar ◽  
You-Tang Shen ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Myocardial Infarction ◽  
Heart Failure ◽  
Cytochrome C ◽  
Protein Expression ◽  
Cell Viability ◽  
Cytochrome C Oxidase ◽  
Mitochondrial Gene

Cytochrome c oxidase (COX) is composed of 13 subunits, of which COX I, II, and III are encoded by a mitochondrial gene. COX I and II function as the main catalytic components, but the function of COX III is unclear. Because myocardial ischemia affects mitochondrial oxidative metabolism, we hypothesized that COX activity and expression would be affected during postischemic cardiomyopathy. This hypothesis was tested in a monkey model following myocardial infarction (MI) and subsequent pacing-induced heart failure (HF). In this model, COX I protein expression was decreased threefold after MI and fourfold after HF ( P < 0.05 vs. sham), whereas COX II expression remained unchanged. COX III protein expression increased 5-fold after MI and further increased 10-fold after HF compared with sham ( P < 0.05 vs. sham). The physiological impact of COX III regulation was examined in vitro. Overexpression of COX III in mitochondria of HL-1 cells resulted in an 80% decrease in COX I, 60% decrease in global COX activity, 60% decrease in cell viability, and threefold increase in apoptosis ( P < 0.05). Oxidative stress induced by H2O2 significantly ( P < 0.05) increased COX III expression. H2O2 decreased cell viability by 47 ± 3% upon overexpression of COX III, but only by 12 ± 5% in control conditions ( P < 0.05). We conclude that ischemic stress in vivo and oxidative stress in vitro lead to upregulation of COX III, followed by downregulation of COX I expression, impaired COX oxidative activity, and increased apoptosis. Therefore, upregulation of COX III may contribute to the increased susceptibility to apoptosis following MI and subsequent HF.

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