With respect to β-carotene (BC), confusing results in rodents and human subjects have been reported on its potential protective/promoting effects on lung cancer ( Reference Krinsky 3 – Reference Omenn, Goodman and Thornquist 5 ) as well as on adiposity ( Reference Serra, Bonet and Puigserver 6 ), which can be related to species-specific differences in its metabolism. Knowledge of nutrients or food components able to influence energy balance, by altering energy expenditure, as well as through effects on the biology of adipose tissue, is potentially useful in designing functional foods or diets to help body weight control. The worldwide increase in obesity prevalence and its associated medical complications has awoken great interest in the identification of the main factors involved in body weight control and in the identification of strategies for its prevention and treatment ( Reference Flier 1, Reference Zimmet, Alberti and Shaw 2 ). In conclusion, RA, but not BC, may have in the ferret comparable effects with those described in rodents, whereas differences concerning BC and RA treatments may be attributable to the different BC metabolism in the present animal model with a lower conversion of BC to RA compared with rodents. RA treatment resulted in a slight decrease in adiposity, decreased cell lipid accumulation and increased UCP1 content, suggesting that the effects of BC on thermogenic capacity are not through RA. To ascertain whether BC effects could be mediated by retinoic acid (RA), 1 week supplementation with RA (0♲5 and 25 mg/kg per d) was also studied. BC supplementation resulted in higher body weight (the high dose), induced depot- and dose-dependent hypertrophy of white adipocytes, decreased the amount of brown-like multilocular adipocytes in the retroperitoneal depot and decreased UCP1 content in different fat depots.
#Duplicate detector ferret windows 10 keygen#
We studied the effects of 6-month supplementation with BC (0♸ and 3♲ mg/kg per d) on adipose tissue morphology and uncoupling protein-1 (UCP1) content. Here, we aimed to characterise in the ferret whether the mentioned changes in body weight could be explained by changes in adipose tissue thermogenic capacity.
These results were some way unexpected considering the condition of BC as a vitamin A precursor and the previous data in rodents showing these compounds as thermogenic activators. We previously described that the intake of pharmacological doses of β-carotene (BC) resulted in higher body weight gain in the ferret ( Mustela putorius furo), an animal model that resembles human subjects in terms of intestinal BC absorption and metabolism.
0 kommentar(er)
