Evidence that 5‐lipoxygenase and acetylated cyclooxygenase 2‐derived eicosanoids regulate leukocyte–endothelial adherence in response to aspirin
Bibliographic record
Abstract
(1) Unlike other nonsteroidal anti-inflammatory drugs that inhibit formation of cyclooxygenase (COX)-dependent eicosanoids, acetylation of COX-2 by aspirin switches eicosanoid biosynthesis from prostaglandin E(2) (PGE(2)) to 15-epi-lipoxin A(4) (15-epi-LXA(4) or aspirin-triggered lipoxin, ATL). ATL formation by activated leukocytes (PMN) requires the intervention of 5-lipoxygenase (5-LOX), an enzyme that is involved in leukotriene B(4) (LTB(4)) formation. (2) In the present study, we have examined the role of acetylated COX-2 and 5-LOX in modulating antiadhesive effects of aspirin on adhesion of PMN to endotoxin (LPS)-primed human umbilical endothelial cells (HUVEC). (3) Treating PMN/HUVEC cocultures with aspirin resulted in a concentration-dependent inhibition of cell-to-cell adhesion induced by LPS. Treating HUVEC with selective COX-2 inhibitors, celecoxib and rofecoxib, caused an approximately 70% reversion of antiadhesive effect of aspirin. In contrast, inhibition of neutrophil's 5-LOX pathway with 1 micro M ZD2138, a selective 5-LOX inhibitor, 1 micro M BAY-X-1005, a FLAP inhibitor, or 100 micro M licofelone, a dual COX/5-LOX inhibitor, did not affect antiadhesive properties of aspirin. (4) Exposure to celecoxib (100 micro M) or rofecoxib (10 micro M) completely suppressed ATL formation caused by aspirin without affecting LTB(4) levels. ZD2138, licofelone and BAY-X-1005 inhibited ATL formation as well as LTB(4) generation. (5) Treatment with LXA(4) reduced PMN adhesion to HUVEC and counteracted the proadhesive effect of celecoxib. In contrast, exposure to Boc-1, an LXA(4) antagonist, counteracts the antiadhesive activities of aspirin. Exposure to U75302, an LTB(4) receptor antagonist, enhances the antiadesive effect of aspirin. (6) Reversal of antiadhesive activities of aspirin by celecoxib was associated with increased expression of LFA-1 on PMN and E-selectin on HUVEC. Addition of LXA(4), ZD2138 and U75302 inhibited these changes. (7) The present results support the notion that inhibition of ATL formation is mechanistically linked to the reversal of the antiadhesive activity of aspirin caused by selective COX-1 inhibitors and suggests that the LTB(4)/ATL balance modulates pro- and antiadhesive activity of nonsteroidal anti-inflammatory drugs at the leukocyte-endothelial cell interface.
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 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 | 0.003 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 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 | 0.001 |
| 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".