Cephalic Phase of Insulin Secretion in Obese Women

Abstract

The cephalic phase of reflex insulin secretion was studied in normoglycemic and normoinsulinemic female patients, obese (more than 30% over IBW) and normal subjects. After an overnight fasting, at the sight of breakfast food, the obese group did not present a cephalic response. Their glycemia and insulinemia levels remained at base levels. One minute after visual and olfactory stimulation, a statistically significant rise in immunoreactive insulin levels which was maintained throughout the test, was observed in the control group.

Food-Related Sensory Stimuli are Able to Promote Pancreatic Polypeptide Elevation Without Evident Cephalic Phase Insulin Secretion in Human Obesity

“…Apart from the possibility that a patient may only have occasional brain-mediated insulin release [9,13,18,19], this case may be tentatively explained by the fact that this "responder" woman had a normal baseline insulin level, unlike the majority of the other patients who were hyperinsulinaemic. It cannot be excluded that baseline hyperinsulinaemia may have an inhibitory effect on the insulin oversecretion promoted by brain-mediated stimuli in many obese patients and that different or weak brain responses may occur in different obese populations [14]. This hypothesis may explain the substantial lack of CPIS in our obese patients as has been suggested by others 1141.…”

“…The data concerning CPIS in obese humans are still rather controversial: it has been reported by some authors to be similar to, or higher than, that observed in normal healthy subjects, but others have found it to be absent or even negative (i.e. less than at baseline) [8,9,11,14,15,18,19]. The interest in CPIS in human obesity is due to the basal hyperinsulinaemia frequently found in obese subjects because a superimposed insulin secretion may represent an additional risk factor favouring weight gain, cardiovascular disease, and hypertension [20,21].…”

“…The cephalic phase of insulin secretion (CPIS: i.e. the insulin release promptly induced by neuro-mediated sensory challenges even before the ingestion of food) has been studied in animals [1 -6]and man [7][8][9][10][11][12][13][14][15][16][17][18][19].…”

Autonomic regulation of islet hormone secretion - Implications for health and disease

“…Also combined tease-feeding and ingestion of non-metabolisable sweetener [126] and sham feeding [127] was found to elicit rapid and reliable insulin responses in normal subjects. Moreover, a rapid increase in circulating insulin after oral glucose, before any increase in circulating glucose, has been shown in normal subjects [128]. The cephalic response of insulin secretion is seen in humans within the first 3±4 min, and therefore, when studying this response it is important to sample at an early time after initiation of the stimulus [127].…”

Nutritional implications of cephalic phase thermogenic responses

“…There is evidence that obese people with insulin resistance have a reduced thermogenic response to feeding (Jequier & Schutz, 1988;Osuna, 1986). A study by Bellisle suggests that this may be related to behavioral attitudes (Bellisle, 1989).…”