Induction of Hepatic Insulin‐Like Growth Factor Binding Protein‐1 (IGFBP‐1) in Rats by Dietary n‐6 Polyunsaturated Fatty Acids
Bibliographic record
Abstract
Abstract. The insulin‐like growth factors (IGFs) are mitogenic polypeptides that have been linked to a variety of normal physiological processes as well as neoplasia. Overexpression of several components of the IGF system is associated with hepatocarcinogenesis in humans and rodents. In rat liver, diets rich in n‐6 polyunsaturated fatty acid (PUFA) enhance the development of preneoplastic lesions and tumors. Therefore, the objective of this study was to determine the effect of these dietary fatty acids on the hepatic expression of the various components of the IGF system. The mRNA levels of IGF‐1 and the type 1 receptor were not different in livers of rats fed a diet containing 20% corn oil (CO) compared with those fed 5% CO. Analysis of the IGF binding proteins revealed that insulin‐like growth factor binding protein‐1 (IGFBP‐1) levels were altered by the amount and type of dietary fat. A 2.5‐fold induction of IGFBP‐1 mRNA occurred within 1 week after the animals were fed the 20% corn oil diet compared with those fed 5% CO and was further enhanced to over 6‐fold after 1 month. Furthermore, IGFBP‐1 protein was only detectable in the livers of animals fed the 20% CO diet. Induction of IGFBP‐1 mRNA (4.5‐fold) also occurred in rats fed a high‐fat diet containing safflower (rich in n‐6 PUFAs) compared with those fed a high‐fat diet containing menhaden oil (rich in n‐3 PUFAs). The induction of IGFBP‐1 mRNA was independent of serum insulin levels and the development of insulin resistance. Since IGFBP‐1 mRNA is upregulated in regenerating liver, we reasoned that the induction of IGFBP‐1 mRNA may be associated with an increase in cell proliferation; however, no difference was observed in the hepatic labeling index of rats fed the 20% CO compared with the 5% CO diet. In summary, these studies show a striking induction by dietary n‐6 PUFAs of hepatic IGFBP‐1, a protein that has been implicated in liver cancer development.
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 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.001 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.002 | 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".