Adiponectin Resistance Develops in Rat Soleus Muscle in Response to High-Fat Diets
Bibliographic record
Abstract
High-fat diets have been shown to induce insulin resistance (IR). High-fat diets have also been shown to produce skeletal muscle resistance to leptin, a recognized insulin-sensitizing cytokine. Similar to leptin, adiponectin (Ad) is a stimulatory cytokine, known to enhance fatty acid (FA) oxidation. However, it is unknown if Ad resistance develops in skeletal muscle following high-fat feeding, and if Ad resistance is a precursor to the ensuing diet-induced IR. The purpose of this study was to determine whether Ad's stimulatory effects on muscle glucose and lipid metabolism would be reduced after exposure to different high-fat diets, and if this Ad resistance was independent of the development of IR. Rats were fed a control (12% kcal fat, CON), high-unsaturated fat (60% kcal safflower oil, SAFF) or high-saturated fat diet (60% kcal lard, LARD) for 4 weeks. Following the dietary intervention, glucose uptake and lipid oxidation and esterification was measured in the presence and absence of Ad (2.5ug/ml) in resting, isolated soleus muscle. All 3 groups had similar rates of basal glucose uptake, but LARD rats showed significantly reduced rates of insulin-stimulated glucose uptake compared to CON and SAFF (+68%, vs.+172%,+184% p=0.001). Ad had no effect on basal or insulin-stimulated glucose uptake in any of the diet treatments. With respect to lipid metabolism, the CON group had a significantly lower basal FA oxidation rate (34.4±2.8 nmol/g vs. 49.8±3.5 SAFF, 46.4±3.4 LARD, p<0.03), and triglyceride esterification (TG) (47.6±3.3 nmol/g vs. 67.9±5.8 SAFF, 66.8±3.4 LARD, p<0.01), compared to both high fat groups, suggesting a diet-induced adaptation by the SAFF and LARD group to the higher fat availability. Ad significantly increased FA oxidation within CON rats (+28%, p=0.03), but had no stimulatory effect on FA oxidation in either high-fat group. Additionally, the FA oxidation: TG esterification ratio in the CON group (0.93±0.1) was greater than both SAFF and LARD (0.56±0.05, 0.68±0.07, p<0.04) when all groups were exposed to Ad. Therefore, we conclude that Ad's ability to stimulate FA oxidation and repartition FA away from storage is blunted in soleus muscle of rats fed either a high saturated or unsaturated fat diet for 4 weeks. In contrast, only rats fed a high saturated fat diet developed IR. We hypothesize that as a result of high-fat feeding, skeletal muscle may become Ad resistant. However, it is unclear whether Ad resistance necessarily leads to IR. Further studies are warranted to determine the long-term effect of polyunsaturated fat on insulin sensitivity.
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) | 0.000 | 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) | 0.001 | 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".