The multi-subunit mammalian NADH-ubiquinone oxidoreductase (complex I) is part of the mitochondrial electron transport chain and physiologically serves to reduce ubiquinone with NADH as the electron donor. The three-dimensional structure of this enzyme complex remains to be elucidated and also little is known about the physiological regulation of complex I. The enzyme complex in vitro is known to exist as a mixture of active (A) and de-active (D) forms [Biochim. Biophys. Acta 1364 (1998) 169]. Studies are reported here examining the effect of anoxia and reperfusion on the A/D-equilibrium of complex I in rat hearts ex vivo. Complex I from the freshly isolated rat heart or after prolonged (1 h) normoxic perfusion exists in almost fully active form (87+/-2%). Either 30 min of nitrogen perfusion or global ischemia decreases the portion of active form of complex I to 40+/-2%. Upon re-oxygenation of cardiac tissue, complex I is converted back predominantly to the active form (80-85%). Abrupt alternation of anoxic and normoxic perfusion allows cycling between the two states of the enzyme. The possible role in the physiological regulation of complex I activity is discussed.

Download full-text PDF

Source
http://dx.doi.org/10.1016/s0005-2728(02)00280-3DOI Listing

Publication Analysis

Top Keywords

active form
12
complex
10
nadh-ubiquinone oxidoreductase
8
oxidoreductase complex
8
complex rat
8
rat heart
8
enzyme complex
8
physiological regulation
8
regulation complex
8
normoxic perfusion
8

Similar Publications

The increasing utilization of deep learning models in drug repositioning has proven to be highly efficient and effective. In this study, we employed an integrated deep-learning model followed by traditional drug screening approach to screen a library of FDA-approved drugs, aiming to identify novel inhibitors targeting the TNF-α converting enzyme (TACE). TACE, also known as ADAM17, plays a crucial role in the inflammatory response by converting pro-TNF-α to its active soluble form and cleaving other inflammatory mediators, making it a promising target for therapeutic intervention in diseases such as rheumatoid arthritis.

View Article and Find Full Text PDF

Bactericidal Metal-Organic Gallium Frameworks - Synthesis to Application.

Mol Pharm

December 2024

Department of Biomedical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States.

Gallium, a trace metal not found in its elemental form in nature, has garnered significant interest as a biocide, given its ability to interfere with iron metabolism in bacteria. Consequently, several gallium compounds have been developed and studied for their antimicrobial properties but face challenges of poor solubility and formulation for delivery. Organizing the metal into three-dimensional, hybrid scaffolds, termed metal-organic frameworks (MOFs), is an emerging platform with potential to address many of these limitations.

View Article and Find Full Text PDF

The observed increase in cases of earwax plugs in patients, as well as the variety of methods of their removal using agents with different cerumenolysis activity, emphasize the need to search for the most modern and multifunctional otolaryngological preparations with proven efficacy. Based on the results of the analysis and generalization of literature sources on the treatment and prevention of ear sulfur plugs, presented in specialized publications in the Russian scientific eLibrary and scientific databases MedLine, Web of Science, Scopus, the need to optimize treatment methods and preventive measures has been identified. In this regard, it is recommended to widely use the preparation A-Cerumen Plus as one of the most progressive means.

View Article and Find Full Text PDF

To study the epidemiological characteristics of chronic tonsillitis (ChT), the need for patients to undergo conservative and surgical treatment, and a comparative assessment of the effectiveness of conservative treatment of patients with chronic tonsillitis using Tonsilotren as monotherapy and in complex treatment. The study involved 999 otorhinolaryngologists from the outpatient network of 20 major Russian cities. The data of 74125 patients diagnosed with ChT were analyzed.

View Article and Find Full Text PDF

Neuronal traveling waves form preferred pathways using synaptic plasticity.

J Comput Neurosci

December 2024

Department of Physics, Drexel University, 3141 Chestnut Street, Philadelphia, 19104, PA, USA.

Traveling waves of neuronal spiking activity are commonly observed across the brain, but their intrinsic function is still a matter of investigation. Experiments suggest that they may be valuable in the consolidation of memory or learning, indicating that consideration of traveling waves in the presence of plasticity might be important. A possible outcome of this consideration is that the synaptic pathways, necessary for the propagation of these waves, will be modified by the waves themselves.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!