Analysis of mitochondrial MMP‐2 and MMP‐9 in the heart
Bibliographic record
Abstract
Matrix metalloproteinase‐2 (MMP‐2) and MMP‐9 have been reported to be in cardiac mitochondria. However, these studies relied on non‐specific immunological methods or crude mitochondrial fractions contaminated with endoplasmic reticulum (ER). To determine if MMP‐2 and ‐9 are in the mitochondria we isolated purified mitochondria from adult rat hearts via Percoll density gradient centrifugation. To confirm mitochondrial purity, we showed that the ER marker protein disulfide isomerase, present in crude mitochondria, was absent in the Percoll‐purified mitochondrial fraction. We detected 72 kDa MMP‐2 via gelatin zymography and western blotting in crude mitochondrial fractions; MMP‐9 was only detected by western blotting. Purified mitochondria did not exhibit MMP‐2 or ‐9 gelatinolytic activities, but showed both MMP‐2 and MMP‐9 protein in western blots. In conclusion, MMPs are present in cardiac mitochondria, however, they appear to be in a form that may be resistant to activation. Future research will investigate several putative mitochondrial targets of MMPs identified by previous non‐biased degradomic screens. Funding: Canadian Institutes of Health Research
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| 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) | 0.001 | 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 source (direct Gemma or distilled Codex), 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".