Krug R, Mohwinkel L, Drotleff B, Born J, Hallschmid M. Insulin and Estrogen Independently and Differentially Reduce Macronutrient Intake in Healthy Men. The Journal of clinical endocrinology and metabolism 2018. Insulin and Estrogen Independently and Differentially Reduce Macronutrient Intake in Healthy Men | The Journal of Clinical Endocrinology & Metabolism | Oxford Academic
Context: Insulin administration to the central nervous system inhibits food intake, but this effect has been found to be less pronounced in female compared to 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 pre-treatment 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 2x2 design, two groups of men (each n=16) received a 3-day transdermal estradiol (100 microg/24 h) or placebo pre-treatment 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.
Context: Insulin administration to the central nervous system inhibits food intake, but this effect has been found to be less pronounced in female compared to 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 pre-treatment 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 2x2 design, two groups of men (each n=16) received a 3-day transdermal estradiol (100 microg/24 h) or placebo pre-treatment 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.
