Remote ischemic preconditioning with but not without metabolic support protects the neonatal porcine heart against ischemia-reperfusion injury
Bibliographic record
Abstract
Purpose: While remote ischemic preconditioning (rIPC) protects the mature heart against ischemia-reperfusion (IR) injury, the effect of rIPC on the neonatal heart is not known. The neonatal heart relies almost solely on carbohydrate metabolism, which is modified by rIPC in the mature heart. Glucose-insulin (GI) infusion provides myocardial substrate supplementation, which may compensate for adverse metabolic effects induced by rIPC in the immature heart. We hypothesized that rIPC combined with GI improves cardiac function and reduces infarcts size compared to control or rIPC alone after IR injury in neonatal piglet in-vivo. Methods: 32 newborn (1-4 days old) piglets were randomized into 4 groups: control, rIPC, GI and GI+rIPC. GI and GI+rIPC groups received insulin in 20% glucose at a rate corresponding to 100 mU/kg/h continuously from 40 minutes prior to ischemia. rIPC and GI+rIPC groups underwent four cycles of 5 minutes limb ischemia followed by 5 minutes reperfusion. Myocardial IR injury was induced by 40 minutes occlusion of the left anterior descending artery followed by 2 hours reperfusion. Left ventricular pressure was measured using 3F Millar Mikro-Tip catheters. Metabolomic assessment of lactate and intermediary metabolites was performed using microdialysis samples analyzed by mass spectrometry. Infarct size was measured using triphenyltetrazolium chloride staining. Results: Systolic recovery (dP/dtmax as % of baseline) after 2h reperfusion was improved in GI+rIPC (86.8±5.8%) compared to control (68.6±4.9%, p<0.05) and rIPC (53.9±8.8%, p<0.01) but not different from GI (83.6±8.2%, ns). Lactate levels (% of baseline) 30 minutes into reperfusion were lower in GI+rIPC (91.5±4.9%) compared to control (182.1±9.1%, p<0.01) and rIPC (235.1±31.1%, p<0.01). Succinate accumulation occurred in all groups as response to IR injury, but this accumulation was strongly accentuated in the rIPC group. Infarct size relative to area at risk was 12.7±1.1% in GI+rIPC compared to 16.4±1.5% in control (p=0.06), 18.1±0.8% in rIPC (p<0.01) and 24.1±2.1% in GI. Conclusion: rIPC+GI, but neither rIPC nor GI alone protects the neonatal porcine heart against IR injury in-vivo. rIPC alone appears to have detrimental metabolic and functional effects that are compensated by simultaneous metabolic support with GI infusion.
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) | 0.001 | 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) | 0.002 | 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".