Bioenergetic remodeling during cellular differentiation: changes in cytochrome <i>c</i> oxidase regulation do not affect the metabolic phenotype
Bibliographic record
Abstract
Myogenesis induces mitochondrial proliferation, a decrease in reactive oxygen species (ROS) production, and an increased reliance upon oxidative phosphorylation. While muscles typically possess 20%-40% excess capacity of cytochrome c oxidase (COX), undifferentiated myoblasts have only 5%-20% of the mitochondrial content of myotubes and muscles. We used two muscle lines (C2C12, Sol8) and 3T3-L1 pre-adipocytes to examine if changes in COX regulation or activity with differentiation cause a shift in metabolic phenotype (i.e., more oxidative, less glycolytic, less ROS). COX activity in vivo can be suppressed by its inhibitor, nitric oxide, or sub-optimal substrate (cytochrome c) concentrations. Inhibition of nitric oxide synthase via L-NAME had no effect on the respiration of adherent undifferentiated cells, although it did stimulate respiration of myoblasts in suspension. While cytochrome c content increased during differentiation, there was no correlation with respiratory rate or reliance on oxidative metabolism. There was no correlation between COX specific activity and oxidative metabolism between cell type or in relation to differentiation. These studies show that, despite the very low activities of COX, undifferentiated myoblasts and pre-adipocytes possess a reserve of COX capacity and changes in COX with differentiation do not trigger the shift in metabolic phenotype.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.000 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".