Browsing by Author "Eiler, William J.A."

Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Ghrelin is not Related to Hunger or Calories Consumed at Breakfast in Lean and Obese Women
    (Office of the Vice Chancellor for Research, 2015-04-17) Morgan, Rachel C.; Acton, Anthony J.; Armstrong, Cheryl L.H.; Eiler, William J.A.; Case, K. Rose; Soeurt, Christina M.; Dzemidzic, Mario; Kareken, David A.; Considine, Robert V.
    Background: The mechanisms that result in greater caloric intake in obese individuals are incompletely understood. Ghrelin administration increases ad lib food intake in humans. We investigated the relationship of ghrelin to calorie consumption and hunger at breakfast on two separate occasions in lean and obese women. Methods: 23 lean (BMI 22.3±0.5 kg/m2, 26.5±1.0 yr) and 25 obese (BMI 36.9±0.7 kg/m2, 27.8±1.1 yr) women participated in a noncontiguous 2 day study. The minimum and maximum days between visits were 6 and 43 days. Participants were given the same breakfast on both days (turkey sausage, French toast with margarine/syrup, fruit cup, coffee, tea, diet soda, or water) with portions adjusted to provide 20% of the daily energy requirement for weight maintenance. Subjects were instructed to eat until full. Hunger was evaluated on a Satiety Labeled Intensity Magnitude Scale (SLIM) before and after the meal. Anchors were “greatest imaginable fullness” at 0 and “greatest imaginable hunger” at 100. Blood samples were collected over 120 minutes for measurement of active ghrelin. Results: Lean subjects consumed an equivalent number of calories on both days (380.0±14.6 vs 378.2±14.9 kcal), as did the obese (419.4±16.2 vs 428.8±15.4 kcal). On average for both days, obese consumed significantly more breakfast calories than lean (424.1±11.1 vs 379.1±10.3 kcal; P<0.01), but the same percentage of calories provided (85.7±1.8 vs 86.1±1.7 %kcal). Lean subjects rated hunger before breakfast the same on both days (69.2±1.6 vs 71.7±1.4), as did the obese (69.8±1.6 vs 69.6±1.8), and there was no difference between the groups. Lean subjects rated hunger after breakfast the same on both days (27.8±1.9 vs 30.3±2.4), as did the obese (25.0±1.7 vs 24.3±1.8). The reduction in hunger score following breakfast was significant for both groups (P<0.0001), with the obese reporting significantly less hunger/more fullness after breakfast than the lean (P=0.02). Fasting ghrelin was significantly greater in the lean than obese women (549.9±58.9 vs 231.0±29.1 pg/ml; P<0.0001). Ghrelin was significantly reduced at 60 min following breakfast in the lean (375.8±49.2 pg/ml; P=0.028) but not the obese (212.2±26.4 pg/ml). Ghrelin was not related to hunger score prior to breakfast, and there was no relationship between reduction in ghrelin and hunger score in the lean or obese. Conclusion: Caloric intake (as a percentage provided) and hunger scores before breakfast on two occasions were the same for both lean and obese women. Fasting ghrelin was significantly different between lean and obese women but did not predict hunger score or calories consumed. Our findings do not support a role for ghrelin in driving food intake at breakfast.
  • Thumbnail Image
    Item
    Pairing Neutral Cues with Alcohol Intoxication: New Findings in Executive and Attention Networks
    (Springer, 2018-09) Oberlin, Brandon G.; Dzemidzic, Mario; Eiler, William J.A.; Carron, Claire R.; Soeurt, Christina M.; Plawecki, Martin H.; Grahame, Nicholas J.; O’Connor, Sean J.; Kareken, David A.; Psychiatry, School of Medicine
    Rationale: Alcohol-associated stimuli capture attention, yet drinkers differ in the precise stimuli that become paired with intoxication. Objectives: Extending our prior work to examine the influence of alcoholism risk factors, we paired abstract visual stimuli with intravenous alcohol delivered covertly and examined brain responses to these Pavlovian conditioned stimuli in fMRI when subjects were not intoxicated. Methods: Sixty healthy drinkers performed task-irrelevant alcohol conditioning that presented geometric shapes as conditioned stimuli. Shapes were paired with a rapidly rising alcohol limb (CS+) using intravenous alcohol infusion targeting a final peak breath alcohol concentration of 0.045 g/dL or saline (CS−) infusion at matched rates. On day two, subjects performed monetary delay discounting outside the scanner to assess delay tolerance and then underwent event-related fMRI while performing the same task with CS+, CS−, and an irrelevant symbol. Results: CS+ elicited stronger activation than CS− in frontoparietal executive/attention and orbitofrontal reward-associated networks. Risk factors including family history, recent drinking, sex, and age of drinking onset did not relate to the [CS+ > CS−] activation. Delay-tolerant choice and [CS+ > CS−] activation in right inferior parietal cortex were positively related. Conclusions: Networks governing executive attention and reward showed enhanced responses to stimuli experimentally paired with intoxication, with the right parietal cortex implicated in both alcohol cue pairing and intertemporal choice. While different from our previous study results in 14 men, we believe this paradigm in a large sample of male and female drinkers offers novel insights into Pavlovian processes less affected by idiosyncratic drug associations.