Exercise Training in Rats Impairs the Replenishment of White Adipose Tissue after Partial Lipectomy

The aim of this study was to evaluate the effect of exercise training on the metabolism of rats following the partial removal of fat pads. Three-month-old male Wistar rats were subjected to the partial removal (L) of retroperitoneal white adipose tissue (RET) and epididymal white adipose tissue (EPI), or a sham operation (Sh). Seven days after surgery, both sets of rats were subdivided into exercised (LE or ShE) (swimming 90 min/day, 5 days/week, 6 weeks) and sedentary (LS or ShS) groups. Partial removal of the fat pads increased the lipogenesis rates in both the RET and EPI and decreased the weight and lypolysis rate of the EPI, while the RET weight was not significantly affected by lipectomy. In both lipectomized and sham-operated groups, exercise training caused a reduction in carcass lipid content, food intake, RET and EPI weights, and RET lipogenesis rate. On the other hand, the exercise training increased the percentage of diet-derived lipid accumulation in both tissues, either in sham and lipectomized rats. These results confirmed that regrowth is not uniform and depends on the particular fat pad that is excised. They also demonstrated that exercise training following the partial removal of fat pads modified adipose tissue metabolism, impaired the replenishment of adipose tissue, and decrease body adiposity.

Hydrogenated Fat Diet Intake during Pregnancy and Lactation Modifies the PAI-1 Gene Expression in White Adipose Tissue of Offspring in Adult Life

We examine whether feeding pregnant and lactating rats hydrogenated fats rich in trans fatty acids modifies the plasma lipid profiles and the expression of adipokines involved with insulin resistance and cardiovascular disease in their 90-day-old offspring. Pregnant and lactating Wistar rats were fed with either a control diet (C group) or one enriched with hydrogenated vegetable fat (T group). Upon weaning, the male pups were sorted into four groups: CC, mothers were receiving C and pups were kept on C; CT, mothers were receiving C and pups were fed with T; TT, mothers were receiving T and pups were kept on T; TC, mothers were receiving T and pups were fed with C. Pups' food intake and body weight were quantified weekly and the pups were killed at day 90 of life by decapitation. Blood and carcass as well as retroperitoneal, epididymal, and subcutaneous white adipose tissues were collected. Food intake and body weight were lower in TC and TT, and metabolic efficiency was reduced in TT. Offspring of TT and TC rats had increased white adipose tissue PAI-1 gene expression. Insulin receptor was higher in TT than other groups. Ingestion of hydrogenated vegetable fat by the mother during gestation and lactation could promote deleterious consequences, even after the withdrawal of the causal factor.