Sweet-Taste Receptor Signaling Network and Low-Calorie Sweeteners

Abstract

Over the past decades, low-calorie sweeteners (LCSs) have emerged as the main source of sweetening food products and beverages. Evidences suggest mixed effects of LCSs intake. In addition, there is a paucity of data on long-term health outcomes of LCSs intake as well as their usefulness in certain groups of the population (e.g., pregnant women, children, and the elderly). Moreover, available unbiased studies conducted to date are fairly scanty, thereby restraining far-reaching conclusions. LCSs are biomolecules with cognate cellular receptors ubiquitously localized in many organs and tissues of the body. The T1R2-T1R3 receptor heterodimer is one of the widely known receptors of LCSs. Upon activation by LCSs, T1R2-T1R3 signals downstream that result in several cellular responses that characterize the biochemical and physiological effects of LCSs. In the gut, for instance, signaling of LCSs may be mediated via humoral and neural mechanisms (involving the gut-brain axis, gut-adipose tissue axis, gut-adipose tissue-brain triangle, gut-pancreas-adipose tissue or entero-adipo-insular triangle, gut-brain-adipose tissue triangle) influence obesity, overweight, appetite, satiety, cognition, and memory. Several interconnected signaling pathways are important in modulating the physiological outcomes of LCS intake. In this chapter, we discuss the signaling mechanisms of LCSs, and their relationship to metabolism, obesity, weight gain, satiety, appetite, cognition, and memory.