Endocrine and Neural Control of Eating in Women
Condition: Normal Body Weight; Obesity
MeSH terms: Body Weight
Study type: Observational

Summary: 
      The purpose of this study is to better understand how female sex hormones influence the food
      intake in the gut system through the release of satiety hormones as well as through central
      regulative mechanisms in the brain that subsequently contribute to the control of eating in
      healthy women at different stages of the ovarian cycle.
    

Detailed description: 
      Obesity and the associated severe consequences for health, i.e. cardiovascular diseases or
      Diabetes Type 2 reach the world-wide level of an epidemic with excessive eating as major
      cause of this development. Study results of veterinary physiology as well as in women let
      assume that steroid hormones, such as estrogen or progesterone are highly involved in the
      regulation of eating behavior and the female body weight. This connection is underpinned with
      the fact that prevalence of adiposity is increased in women in comparison to men in the
      United States, Switzerland and further countries. A better understanding of the underlying
      regulatory mechanisms, which in turn influence the food intake in the gut system through the
      release of satiety hormones as well as through central regulative mechanisms in the brain,
      provides important foundation in long-term development of new prophylactic and therapeutic
      options in reduction and prevention of obesity. This gets even more important, as current
      therapeutic options - beside bariatric surgery - could only show limited success.

      Satiety is a process in the brain that leads to a meal being ended, whereby the ingested food
      causes a reflexive negative feedback mechanism. This mechanism is both fundamentally and
      specifically in the acute situation strongly influenced through subjective parameters, e.g.
      eating desires, socio-cultural factors, current social circumstances and individual relation
      towards eating. Furthermore, food intake is also influenced by genetic factors, whereas e.g.
      TaqIA1 allele is known to be associated with obesity. According to current knowledge,
      regulation takes place on peripheral as well as on central level, whereas not only steroid
      hormones but also satiety hormones - especially cholecystokinin (CCK) and glucagon-like
      peptide-1 (GLP-1) - are involved on both levels.

      The current study aims to examine the connection of steroid hormones, gastrointestinal
      satiety hormones and neuronal activity in the brain through fMRI. Through the obtained data,
      the interaction between defined hormone constellations, gastrointestinal satiety hormones and
      the activation of specific brain areas in obese and normal-weight women should be evaluated.
      The study design involves the comparison of subjective, hedonic evaluation of different
      flavoured liquids with different caloric content each through a rating scale as well as
      objective peripheral (release of CCK and GLP-1) and central (activation of involved brain
      centres through fMRI) regulation processes in fasted and fed condition of each woman in the
      two study groups (obese and normal-weighted) in late follicular compared with the luteal
      phase of ovarian cycle.
    

Observational model: Case-Control
Time perspective: Cross-Sectional
Sampling method: Probability Sample
Study population: 
        Normal-weight and obese women with regular menstrual cycles.
      
Biospecimen description: 
      Whole blood to determine hormonal parameters (gut hormones and reproductive hormones) and the
      presence of the gene TaqIA1.
    
Keywords: Obesity; Menstrual Cycle; Gonadal Steroid Hormones; Satiety Response; Glucagon-Like Peptide 1; Cholecystokinin; Magnetic Resonance Imaging