Investigating the Role of 2-Phenylpropenal in Felbamate-Induced Idiosyncratic Drug Reactions
Bibliographic record
Abstract
Felbamate (2-phenyl-1,3-propanediol dicarbamate, FBM) can cause aplastic anemia and hepatotoxicity. The mechanism of FBM-induced toxicities is unknown; however, it has been proposed that 2-phenylpropenal, a reactive metabolite of FBM, is responsible. The pathway leading to this metabolite involves hydrolysis of FBM to 2-phenyl-1,3-propandiol monocarbamate (MCF), oxidation to 3-carbamoyl-2-phenylpropionaldehyde (CBMA), and spontaneous loss of carbon dioxide and ammonia. We made a polyclonal antibody against 2-phenylpropenal bound to protein and confirmed its specificity using ELISA. We attempted to develop an animal model of FBM-induced aplastic anemia and/or hepatotoxicity, and we also used the antibody to try to detect covalent binding of 2-phenylpropenal using immunoblotting. However, none of the animals developed evidence of bone marrow or liver toxicity, and we were unable to detect covalent binding, possibly because significantly less 2-phenylpropenal is formed in rodents than in humans. As this type of idiosyncratic drug reaction is believed to be immune-mediated, we also studied the potential of FBM and its metabolites to stimulate an immune response using the reporter antigen popliteal lymph node assay in female Balb/c mice. We found that neither FBM nor MCF induced an immune response in popliteal lymph nodes (PLNs). However, CBMA treatment appeared immunogenic, causing footpad inflammation, hardening, scab formation, and an increase in thickness. The PLN cell count in CBMA-treated mice increased 8-fold as compared to control, FBM-, or MCF-treated mice. Immunohistochemical analysis of the CBMA-exposed PLNs revealed germinal center formation, indicating B cell proliferation, later confirmed by flow cytometry. Most of the cells expressing the activation surface marker CD54 were B cells. We also found that CBMA treatment caused an increase in the production of IgM and IgG1 antibodies as well as IL-4 and IFN-gamma cytokines. Our findings indicate that 2-phenylpropenal is a very potent immunogen, supporting its possible involvement in the FBM-induced hepatotoxicity and aplastic anemia.
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 | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.001 |
| 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".