The Acute Salivary Ghrelin Response to a Psychosocial Stress Is Enhanced in Symptomatic Patients with Bulimia Nervosa: A Pilot Study

Abstract

Background: Stress is a precipitating factor for both binge eating and bulimia nervosa (BN); however, the biological mechanisms through which it may trigger binge eating are poorly understood. There is evidence that the adrenal hormone cortisol and the gastric peptide ghrelin might be involved in stress-induced food ingestion. We hypothesized that symptomatic patients with BN might disclose deranged responses of ghrelin and/or cortisol to stressors and that this could be related to their binge-eating behaviour. Methods: Here we investigated salivary cortisol and ghrelin responses to the Trier Social Stress Test (TSST) in 10 women with acute BN and 10 age-matched healthy females. Eating-related psychopathology and behaviours were assessed by self-report measures. Results: No significant differences emerged between bulimic patients and healthy controls in the pre-stress salivary levels of both cortisol and ghrelin. The BN patients displayed normal cortisol but enhanced ghrelin responses to TSST. No significant correlations emerged between stress-induced salivary hormone changes and self-report measures of binge eating. Conclusion: To our knowledge, this is the first study showing deranged salivary ghrelin reactivity to a psychosocial stressor in symptomatic patients with BN. The extent to which this could contribute to the binge-eating behaviour of BN subjects awaits clarification.

Investigation on Serum Hormonal Parameters (Ghrelin, Corticosterone, Insulin, T3 and T4) in Chronic Mild Stress Rat Model of Depression

“…Investigations on major depression cases show constant level for ghrelin [2] . Findings of present study for ghrelin levels of depressed (CMS) animals (Table 2) are in agreement with Chuang and Zigman [17] , Asakawa et al [19] , Kristenssson et al [20] and Monteleone et al [24] reports witch indicate that ghrelin can increase in chronic psychological or environmental stress, and various protocols for depression induce.…”

“…Another evidence for regulatory role of ghrelin in stressful condition is that ghrelin elevation occures along with epinephrine raises induced with stress [23] . Monteleone et al [24] reported considerable increase in salivary ghrelin following social stress protocol. Investigations on major depression cases show constant level for ghrelin [2] .…”

Ghrelin Levels After a Cold Pressor Stress Test in Obese Women With Binge Eating Disorder

“…In recent studies, both intravenous ghrelin infusions (51) and fasting ghrelin levels (52) were positively correlated with neural responses elicited by pictures of palatable food shown to healthy volunteers during functional magnetic resonance imaging, particularly in brain regions implicated in areas that control appetitive behavior. These studies support the notion that, in accordance with the affect-regulation model, the ghrelin rise we observed after stress exposure could lead to increased food intake as an attempt to replace negative emotions with the rewarding, positive feelings of pleasure achieved by the ingestion of food (33). …”

“…In a recent study, there was a significantly longer and greater salivary ghrelin increase in patients with BN compared with controls after the TSST (33), although it is unclear to what extent salivary ghrelin reflects circulating ghrelin. In the same study, the authors did not observe differences in cortisol levels after TSST in patients with BN compared with controls (33). In a previous study from our group, we found a trend for increased cortisol levels and hunger ratings after CPT in BED compared with non-BED (22).…”

“…Ghrelin levels have recently been reported in BED, with lower fasting ghrelin (29,30) and a smaller postprandial decline in BED than in non-BED obese individuals (30,31). Ghrelin levels were activated after acute psychological stress in a recent study of rats (32) and in women with and without BN (33) and the night eating syndrome (34), although other reports in humans are inconsistent (35). …”