Abstract 175: Doxorubicin and Acute Exercise Training Impair Diastolic Before Systolic Function in a Murine Model of Cancer
Bibliographic record
Abstract
Introduction: Cardiotoxicity often occurs in cancer patients treated with doxorubicin (DOX). DOX induces cardiomyocyte death, due in part to DOX-mediated DNA damage, myofiber degeneration, ischemia-related metabolic alterations, and activation of apoptotic pathways. While exercise is often recommended for cancer patients, it remains unclear whether the metabolic stress of exercise with DOX treatment benefits or impairs cardiac performance. Purpose: To test the hypothesis that acute exercise training performed with DOX therapy offsets cardiotoxicity. Methods: B16F10 melanoma cells (3x10 5 ) were injected into 6-8 week old male C57BL/6 mice (n= 48). A 4 mg/kg cumulative dose of DOX (IP) was administered over 2 weeks and exercise (EX) consisted of treadmill walking (45 min/d, 10 m/min, 5 days/week, 2 weeks). Four groups were tested: 1) Sedentary (SED) +Vehicle, 2) SED +DOX, 3) EX+Vehicle, 4) EX+DOX. Echocardiography [LV systolic (EF, %) and diastolic (E/A ratio) function] and tissue harvest were performed 48 hours after EX. Results: Tumor volume was attenuated in DOX and lowest in EX+DOX (p<0.05). Body weight (BW), heart weight (HT), HT/BW, and HT/Tibia were attenuated in DOX (p<0.05) and were lowest in EX+DOX. LV fibrosis increased with DOX (p<0.05) and was greatest in EX+DOX (SED+Vehicle 2 ± 0.3%, SED+DOX 4 ± 0.5%, EX+Vehicle 3 ± 0.3%, and EX+DOX 6 ± 0.4%; p<0.05). Cardiomyocyte area and β myosin heavy chain gene expression were similar between groups. Diastolic function was reduced with DOX and EX+DOX (both p<0.05), but systolic function was similar between groups. DOX induced significant alterations the expression profiles of genes in the mTOR signaling pathway, with similar expression patterns in SED+DOX and EX+DOX. Insulin improved in vitro cardiomyocyte cell survival (p<0.05) to a greater extent than IGF-1 treatment during DOX. Neither insulin nor IGF-1 impacted cardiomyocyte proliferation during DOX. Conclusion: While the addition of EX to DOX treatment more effectively inhibited tumor growth, EX did not alleviate DOX mediated LV diastolic impairment, and actually increased LV fibrosis. Acute, short term exercise appears to impair LV function in DOX-treated mice. Exercise-induced reductions in insulin secretion may underlie this effect.
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) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.002 |
| Insufficient payload (model declined to judge) | 0.004 | 0.001 |
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".