title: Higher TNF-α, IGF-1, and Leptin Levels are Found in Tasters than Non-Tasters.
abstract: Taste perception is controlled by taste cells that are present in the tongue that produce and secrete various metabolic hormones. Recent studies have demonstrated that taste receptors in tongue, gut, and pancreas are associated with local hormone secretion. The aim of this study was to determine whether there is a link between taste sensitivity and levels of circulating metabolic hormones in humans and whether taste sensitivity is potentially related to peripheral metabolic regulation. Thirty-one subjects were recruited and separated into tasters and non-tasters based on their phenol thiocarbamide (PTC) bitter taste test results. Fasting plasma and saliva were collected and levels of hormones and cytokines were assayed. We observed significant differences in both hormone levels and hormone-body mass index (BMI) correlation between tasters and non-tasters. Tasters had higher plasma levels of leptin (p = 0.05), tumor necrosis factor-α (TNF-α) (p = 0.04), and insulin-like growth factor 1 (IGF-1) (p = 0.03). There was also a trend toward increased IGF-1 levels in the saliva of tasters (p = 0.06). We found a positive correlation between plasma levels of glucose and BMI (R = 0.4999, p = 0.04) exclusively in non-tasters. In contrast, plasma C-peptide levels were found to be positively correlated to BMI (R = 0.5563, p = 0.03) in tasters. Saliva TNF-α levels were negatively correlated with BMI in tasters (R = -0.5908, p = 0.03). Our findings demonstrate that there are differences in circulating levels of leptin, TNF-α, and IGF-1 between tasters and non-tasters. These findings indicate that in addition to the regulation of food consumption, taste perception also appears to be tightly linked to circulating metabolic hormone levels. People with different taste sensitivity may respond differently to the nutrient stimulation. Further work investigating the link between taste perception and peripheral metabolic control could potentially lead to the development of novel therapies for obesity or Type 2 diabetes.
authors.affiliation: Metabolism Unit, National Institute on Aging, National Institutes of Health , Baltimore, MD , USA.
authors.forename: Rui
authors.initials: R
authors.lastname: Wang
authors.affiliation: Department of Internal Medicine, Onze Lieve Vrouwe Gasthuis , Amsterdam , Netherlands.
authors.forename: Nika M A
authors.initials: NM
authors.lastname: van Keeken
authors.affiliation: Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health , Baltimore, MD , USA.
authors.forename: Sana
authors.initials: S
authors.lastname: Siddiqui
authors.affiliation: Teaching Hospital, Onze Lieve Vrouwe Gasthuis , Amsterdam , Netherlands.
authors.forename: Lea M
authors.initials: LM
authors.lastname: Dijksman
authors.affiliation: Receptor Pharmacology Unit, National Institute on Aging, National Institutes of Health , Baltimore, MD , USA ; VIB Department of Molecular Genetics, University of Antwerp , Antwerp , Belgium.
authors.forename: Stuart
authors.initials: S
authors.lastname: Maudsley
authors.affiliation: Better Immune System Foundation , Amsterdam , Netherlands.
authors.forename: Diana
authors.initials: D
authors.lastname: Derval
authors.affiliation: Department of Internal Medicine, Onze Lieve Vrouwe Gasthuis , Amsterdam , Netherlands.
authors.forename: P Sytze
authors.initials: PS
authors.lastname: van Dam
authors.affiliation: Metabolism Unit, National Institute on Aging, National Institutes of Health , Baltimore, MD , USA.
authors.forename: Bronwen
authors.initials: B
authors.lastname: Martin
keywords: BMI; IGF-1; TNF-α; leptin; taste