Rosemarie Krug1, Linda Mohwinkel2, Bernhard Drotleff3, Jan Born1,4,5, Manfred Hallschmid1,4,5. 1. Department of Medical Psychology and Behavioral Neurobiology, University of Tübingen, Tübingen, Germany. 2. Department of Neuroendocrinology, University of Lübeck, Lübeck, Germany. 3. Institute of Pharmaceutical Sciences, University of Tübingen, Tübingen, Germany. 4. German Center for Diabetes Research (DZD), München-Neuherberg, Germany. 5. Institute for Diabetes Research and Metabolic Diseases of the Helmholtz Center Munich at the University of Tübingen (IDM), Tübingen, Germany.
Abstract
Context: Insulin administration to the central nervous system inhibits food intake, but this effect has been found to be less pronounced in female compared with male organisms. This sex-specific pattern has been suggested to arise from a modulating influence of estrogen signaling on the insulin effect. Objective: We assessed in healthy young men whether pretreatment with transdermal estradiol interacts with the hypophagic effect of central nervous insulin administration via the intranasal pathway. Design, Setting, Participants, and Intervention: According to a 2×2 design, two groups of men (n = 16 in each group) received a 3-day transdermal estradiol (100 µg/24 h) or placebo pretreatment and on two separate mornings were intranasally administered 160 IU regular human insulin or placebo. Main Outcome Measures: We assessed free-choice ad libitum calorie intake from a rich breakfast buffet and relevant blood parameters in samples collected before and after breakfast. Results: Estrogen treatment induced a 3.5-fold increase in serum estradiol concentrations and suppressed serum testosterone concentrations by 70%. Independent of estradiol administration, intranasal insulin reduced the intake of carbohydrates during breakfast, attenuating in particular the consumption of sweet, palatable foods. Estradiol treatment per se decreased protein consumption. We did not find indicators of eating-related interactions between both hormones. Conclusions: Results indicate that, in an acute setting, estrogen does not interact with central nervous insulin signaling in the control of eating behavior in healthy men. Insulin and estradiol rather exert independent inhibiting effects on macronutrient intake.
RCT Entities:
Context:Insulin administration to the central nervous system inhibits food intake, but this effect has been found to be less pronounced in female compared with male organisms. This sex-specific pattern has been suggested to arise from a modulating influence of estrogen signaling on the insulin effect. Objective: We assessed in healthy young men whether pretreatment with transdermal estradiol interacts with the hypophagic effect of central nervous insulin administration via the intranasal pathway. Design, Setting, Participants, and Intervention: According to a 2×2 design, two groups of men (n = 16 in each group) received a 3-day transdermal estradiol (100 µg/24 h) or placebo pretreatment and on two separate mornings were intranasally administered 160 IU regular humaninsulin or placebo. Main Outcome Measures: We assessed free-choice ad libitum calorie intake from a rich breakfast buffet and relevant blood parameters in samples collected before and after breakfast. Results: Estrogen treatment induced a 3.5-fold increase in serum estradiol concentrations and suppressed serum testosterone concentrations by 70%. Independent of estradiol administration, intranasal insulin reduced the intake of carbohydrates during breakfast, attenuating in particular the consumption of sweet, palatable foods. Estradiol treatment per se decreased protein consumption. We did not find indicators of eating-related interactions between both hormones. Conclusions: Results indicate that, in an acute setting, estrogen does not interact with central nervous insulin signaling in the control of eating behavior in healthy men. Insulin and estradiol rather exert independent inhibiting effects on macronutrient intake.
Authors: Elizabeth Schneider; Maartje S Spetter; Elizabeth Martin; Elizabeth Sapey; Kay Por Yip; Konstantinos N Manolopoulos; Abd A Tahrani; Jason M Thomas; Michelle Lee; Manfred Hallschmid; Pia Rotshtein; Colin T Dourish; Suzanne Higgs Journal: Int J Obes (Lond) Date: 2022-04-09 Impact factor: 5.551