The goal of this study is to understand how exogenous kisspeptin affects metabolism by evaluating responses to an oral glucose tolerance test

Assignment: Each study subject will serve as their own control. The order of the visits will be randomized.

Delivery of Interventions:

• Prior to the study visit, subjects will undergo a review of their medical history and screening laboratories.

• During the inpatient study, the subjects will

  • Undergo a 16-hour kisspeptin infusion
  • Undergo an oral glucose tolerance test

Inclusion Criteria:

History:

• over the age of 18,
• normal pubertal development
• stable weight for previous three months,
• normal body mass index (BMI between 18.5-25)
• regular menstrual cycles

Physical examination:

• systolic BP < 140 mm Hg, diastolic < 90 mm Hg

Laboratory studies: (per Massachusetts General Hospital reference ranges)

• normal hemoglobin
• hemoglobin A1C < 6.5%
• blood urea nitrogen, creatinine not elevated
• aspartate aminotransferase, alanine aminotransferase < 3x upper limit of normal

Exclusion Criteria:

• active illicit drug use,
• history of a medication reaction requiring emergency medical care,
• difficulty with blood draws.
• history of chronic disease, except well controlled thyroid disease,
• recent use of prescription medications which interfere with metabolism or reproduction (recent = within 5 half-lives of the drug). Use of levothyroxine or seasonal allergy medications is acceptable,
• history of diabetes in a first degree relative,
• use of contraceptive pills, patches or vaginal rings within last 4 weeks.
• hyperlipidemia by fasting lipid panel
• positive serum pregnancy test (for all women)

From time of study consent until study completion (approximately 5 months).

All participants were asked about new health symptoms at each visit.

This was designed as a pilot study