Oro-gustatory perception of dietary lipids and calcium signaling in taste bud cells are altered in nutritionally obesity-prone Psammomys obesus.
Since the increasing prevalence of obesity is one of the major health problems of the modern era, understanding the mechanisms of oro-gustatory detection of dietary fat is critical for the prevention and treatment of obesity. We have conducted the present study on Psammomys obesus, the rodent desert gerbil which is a unique polygenic natural animal model of obesity. Our results show that obese animals exhibit a strong preference for lipid solutions in a two-bottle test. Interestingly, the expression of CD36, a lipido-receptor, in taste buds cells (TBC), isolated from circumvallate papillae, was decreased at mRNA level, but remained unaltered at protein level, in obese animals. We further studied the effects of linoleic acid (LA), a long-chain fatty acid, on the increases in free intracellular calcium (Ca(2+)) concentrations, [Ca(2+)]i, in the TBC of P. obesus. LA induced increases in [Ca(2+)]i, largely via CD36, from intracellular pool, followed by the opening of store-operated Ca(2+) (SOC) channels in the TBC of these animals. The action of this fatty acid on the increases in [Ca(2+)]i was higher in obese animals than that in controls. However, the release of Ca(2+) from intracellular stores, studied also by employing thapsigargin, was lower in TBC of obese animals than control rodents. In this study, we show, for the first time, that increased lipid intake and altered Ca(2+) signaling in TBC are associated with obesity in Psammomys obesus.
Physiologie de la Nutrition & Toxicologie, UMR U866 INSERM/Université de Bourgogne/Agro-Sup, Dijon, France.
Souleymane
S
Abdoul-Azize
Feriel
F
Atek-Mebarki
Arezki
A
Bitam
Hassimi
H
Sadou
Elhadj Ahmed
EA
Koceïr
Naim Akhtar
NA
Khan
D000818:Animals; D018955:CD36 Antigens / Q000235:genetics / Q000378:metabolism; D020013:Calcium Signaling / Q000187:drug effects*; D004041:Dietary Fats / Q000494:pharmacology*; D004198:Disease Susceptibility; D005518:Food Preferences / Q000187:drug effects; D005786:Gene Expression Regulation / Q000187:drug effects; D005849:Gerbillinae; D019787:Linoleic Acid / Q000494:pharmacology; D008297:Male; D009765:Obesity / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology*; D013650:Taste Buds / Q000187:drug effects / Q000378:metabolism / Q000473:pathology* / Q000503:physiopathology; D055697:Taste Perception / Q000187:drug effects*; D019284:Thapsigargin / Q000494:pharmacology
D018955:CD36 Antigens; D004041:Dietary Fats; D019284:Thapsigargin; D019787:Linoleic Acid