Diurnal Variability in the Regulation of Beta-cell Function and Insulin Sensitivity in Overweight People

Overweight Clinical Trial

— 24Hr  

Official title:

Diurnal Variability in the Regulation of Beta-cell Function and Insulin Sensitivity in Overweight People

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02011581
• Other study ID #: 2011-09110
• Status: Completed
• Phase: N/A
• First received: December 9, 2013
• Last updated: April 28, 2015
• Start date: October 2011
• Est. completion date: March 2014

Study information

• Verified date: April 2015
• Source: Washington University School of Medicine
• Contact: n/a
• Is FDA regulated: No
• Health authority: United States: Institutional Review Board
• Study type: Observational

Clinical Trial Summary

The purpose of this research study is to learn more about how our body produces sugar, breaks down fat for fuel, and makes insulin (the major hormone that controls the production of blood sugar and fat breakdown) during a 24-hour day and how body fat and muscle are involved in these processes.

Description:

The purpose of this study is to determine whether there are diurnal differences in postprandial beta-cell function and hepatic insulin sensitivity and the factors that influence these metabolic functions, including insulin signaling, adipose tissue and systemic inflammation, nicotinamide phosphoribosyltransferase (NAMPT)-mediated nicotinamide adenine dinucleotide(NAD) biosynthesis, and sirtuin (silent mating type information regulation 2 homolog 1 (SIRT1)) in overweight human subjects.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 16
• Est. completion date: March 2014
• Est. primary completion date: December 2013
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Female
• Age group: 18 Years to 55 Years

Eligibility

Inclusion Criteria:

• Females

• 18-55 years old

• BMI between 25.0-29.9 kg/m2

• Must be sedentary (regular exercise <1hour/week or <2 times/week

Exclusion Criteria:

• Regular exercise (>1hour/week or >2 times/week)

• Diabetes

• Severe organ dysfunction

• Smokers

• Severe hypertriglyceridemia (>300 mg/dl)

• Medications that may alter the results of the study

• Pregnant

• Breastfeeding

Study Design

Observational Model: Case Control, Time Perspective: Cross-Sectional

Related Conditions & MeSH terms

• Overweight

Locations

Country	Name	City	State
United States	Washington University School of Medicine	St. Louis	Missouri

Sponsors (1)

Lead Sponsor	Collaborator
Washington University School of Medicine

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Determine postprandial beta-cell function (insulin secretion) after ingesting breakfast and dinner meals.	Postprandial pancreatic beta-cell function will be evaluated by using a mixed meal labelled with stable isotope tracers, in conjunction with stable isotope tracer infusion. Metabolic outcomes from the breakfast meal will be compared with values obtained after dinner.	24 hours	No
Primary	Determine postprandial hepatic insulin sensitivity (suppression of endogenous glucose production) after ingesting breakfast and dinner meals.	Postprandial pancreatic hepatic insulin sensitivity will be evaluated by using a mixed meal labelled with stable isotope tracers, in conjunction with stable isotope tracer infusion. Metabolic outcomes from the breakfast meal will be compared with values obtained after dinner.	24 hours	No
Secondary	Determine whether there is diurnal variability in muscle insulin signaling	This muscle samples will be obtained two times (every 12 hours for 24 hours)to assess NAMPT and NAD+ concentrations, SIRT1 activity, and factors involved in insulin signaling.	24 hours	No
Secondary	Determine whether there is diurnal variability in adipose tissue and systemic inflammation.	Subcutaneous adipose tissue samples will be obtained four times (every 6 hours for 24 hours) to evaluate NAMPT and NAD+ concentrations, SIRT1 activity, and markers of inflammation.	24 hours	No
Secondary	Determine whether there is diurnal variability in NAMPT-mediated NAD+ biosynthesis and SIRT1.	Blood samples will be obtained at regular intervals for 24 hours to evaluate; 1)plasma free fatty acids (FFA), glucose and insulin concentrations, 2)NAMPT and NAD+ concentrations, 3)SIRT1 activity,and 4)systemic markers of inflammation (C-reactive protein and interleukin (IL) -6).	24 hours	No