Oestradiol Differentially Influences Feeding Behaviour Depending on Diet Composition in Female Rhesus Monkeys

Abstract

In females, cyclical changes in the ovarian hormone oestradiol are known to modulate feeding behaviour. However, what is less clear is how these behavioural effects of oestradiol are modified by the macronutrient content of a diet. Here we present data showing that oestradiol treatment results in both significantly smaller meals and reduced total caloric intake in ovariectomised, socially housed female rhesus macaques when only chow diet is available. Conversely, during a choice dietary condition where both palatable and chow options are available, oestradiol treatment had no observable, attenuating effect on caloric intake. During this choice dietary phase, all animals consumed more of the palatable diet than chow diet; however, oestradiol treatment appeared to further increase preference for the palatable diet. Finally, oestradiol treatment increased snacking behaviour, i.e. consumption of calories outside of empirically defined meals, regardless of diet condition. These findings illustrate how oestradiol differentially influences feeding behaviour depending on the dietary environment and provides a framework in which we can begin to examine the mechanisms underlying these observed changes.

Understanding the control of ingestive behavior in primates

“…However, during this dietary choice condition, estradiol had no effect on food intake compared with the no treatment condition. Indeed, estradiol appeared to increase consumption of the HCD compared with the no treatment condition (Johnson et al, 2013). These data suggest that the palatability and macronutrient content of the diet may engage neural circuitry that desensitizes the suppressive effects of estradiol on food intake.…”

“…Those studies in rodents and humans that have examined estradiol’s effect on dietary preference show no consistent effect of estradiol on the selection of particular diet (for review see (Dye and Blundell, 1997)). However, a recent report in adult female rhesus monkeys examined the effect of estradiol on caloric intake when animals were fed the typical low caloric laboratory diet (LCD) or given a choice between this LCD and a more palatable high caloric diet (HCD) containing fat and sugar (Johnson et al, 2013). Females were ovariectomized and were studied in both dietary conditions under either no hormone replacement or during estradiol treatment that mimicked mid-follicular phase concentrations.…”

Stress-induced alterations in estradiol sensitivity increase risk for obesity in women

“…E2 is typically considered an anorexic hormone [97, 98], as food intake during the follicular phase of the menstrual cycle, wherein E2 levels are high in women, is attenuated in comparison to the luteal phase of the cycle [99–102]. Similarly, E2 replacement in ovariectomized adult rhesus monkeys to serum levels characteristic of the follicular phase significantly reduces meal size and number [98].…”

“…Similarly, E2 replacement in ovariectomized adult rhesus monkeys to serum levels characteristic of the follicular phase significantly reduces meal size and number [98]. However, this anorectic effect of E2 is diet dependent, as it is only seen when animals are fed a LCD [98].…”

“…Similarly, E2 replacement in ovariectomized adult rhesus monkeys to serum levels characteristic of the follicular phase significantly reduces meal size and number [98]. However, this anorectic effect of E2 is diet dependent, as it is only seen when animals are fed a LCD [98]. When female monkeys are maintained in a dietary environment where both a LCD and CDD are available, E2 does not attenuate total caloric intake [98] and increases preference for the CDD [98].…”