Starvation Effect on Androgen Metabolism in Healthy Young Women.

The first aim of this study is to investigate the energy homeostasis and the steroid metabolism of healthy, young and normal weight women aged 16-35 years, before and after a 48 hours fasting period. Furthermore, second aim of this study is the comparison of their steroid profiles with PCOS women in search for specific differences.

In fact it might be therefore hypothesized that the energy metabolism in PCOS women functions like under (glucose) starvation conditions. In a pilot experiment performed in a healthy young women of normal weight, the investigators observed that short term starvation over 48 hours changed her steroid profile from normal to PCOS-like with elevated testosterone with elevated testosterone, DHT and androsterone/etiocholanolone ratio. It has been suggested that during normal fasting and feeding metabolic signals such as AMP/NAD+ and acetyl-CoA translate the energy state into specific metabolic programs. The investigators suggest that androgen biosynthesis might be one of these programs. Therefore, becoming hyperandrogenic during short term starvation might be normal, and the regulation between energy balance and androgen biosynthesis might be visible in healthy subjects, thereby hinting pathways leading to PCOS and better treatment options.

In this study the investigators will recruit 20 healthy, normal weight women aged 16-35 years with regular cycle and without drug treatment, including hormonal contraception. Characteristics of the participant and written informed consent with the study will be collected. The study will start 14-21 days after the last menstrual period of the participant. Twenty-four hours prior the first study visit the participant will collect a 24 hours urine sample and a spot urine.

On day one of the study, the participant will come early morning for the first visit to the Inselspital Bern. The participant will be informed again and the exact study protocol will be explained to make sure the participant is willing to fulfil the study requirements. The investigators will draw blood, perform a pregnancy test and collect the 24 hours urine as well as a spot urine. At this point the starvation period will start (=intake to a maximum of 500-800 kcal/d for 24 hours, depends on the weight of the participant). A dietary plan is provided by Mrs. T. Zürcher, Pediatric Dietician, Childrens' Hosp. Inselspital Berne.

This regimen is selected on the basis that the human body switches into a state of "hunger" and starts to burn fat instead of glucose after about 12 hours. During a 48 hours fasting period the metabolism changes dramatically. During this state hormonal and chemical changes will be investigated in blood and urine samples. During the starvation the participants have to stick strictly to the dietary restriction regimen, which they will monitor themselves. If the participants fails to do so, they will be excluded from continuation of the study and cannot participate a second time. Fasting state and thus compliance are visible in the measured lab data (e.g. ketone bodies).