Soy Protein Intake and the Metabolic Syndrome

Metabolic Syndrome X Clinical Trial

— SOY  

Official title:

Soy Protein Intake and the Metabolic Syndrome: Reducing Inflammation to Improve Insulin Resistance and Glucose Homeostasis

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT01694056
• Other study ID #: NL39991.081.12
• Status: Completed
• Phase: N/A
• First received: September 4, 2012
• Last updated: January 3, 2013
• Start date: September 2012
• Est. completion date: December 2012

Study information

• Verified date: January 2013
• Source: Wageningen University
• Contact: n/a
• Is FDA regulated: No
• Health authority: Netherlands: The Central Committee on Research Involving Human Subjects (CCMO)
• Study type: Interventional

Clinical Trial Summary

Soy protein has a high biological value, and contains several potential health-related nutritional factors, i.e. its amino acids pattern, biological active peptides and non-protein compounds such as isoflavones. In the field of obesity and blood lipids soy protein is well-studied and appreciated; it improves circulating blood lipids and is associated with weight reduction. The effect of soy on insulin resistance, glucose homeostasis and the metabolic syndrome is less frequently studied. However, several molecular mechanisms of action of soy protein make it a promising approach.

Description:

Objective: The primary objective of the present study is to evaluate the effect of a high soy protein diet on insulin resistance and glycemic control in participants with characteristics of the metabolic syndrome. Secondly, the present study will evaluate whether reduced low-grade inflammation is a possible mechanism underlying the improvement in insulin resistance and glucose homeostasis. Finally, it will be assessed whether soy protein has beneficial effects on components of the metabolic syndrome, such as cardio-metabolic risk factors, blood lipid profile, blood pressure and endothelial function, fat storage in the liver and gene-expression in subcutaneous abdominal adipose tissue.

Study design: Single-blind, cross-over strictly-controlled dietary intervention.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 15
• Est. completion date: December 2012
• Est. primary completion date: December 2012
• Accepts healthy volunteers: Accepts Healthy Volunteers
• Gender: Female
• Age group: 45 Years to 70 Years

Eligibility

Inclusion Criteria:

• Women

• 45-70 years

• No menstrual cycle for =1 year

• Stable body weight for =6 months (no weight gain/loss > 3 kg)

• Stable exercise habits during the last 6 months, and not participating in any vigorous exercise program

• Central obesity: waist circumference =80 cm

Plus any one of the following four factors:

• Raised triglyceride level: =1.7 mmol/L;

• Reduced high-density lipoprotein (HDL) cholesterol: <1.29 mmol/L

• Raised blood pressure: systolic blood pressure =135 mmHg or diastolic BP =85 mmHg or use of blood pressure lowering medication

• Raised fasting plasma glucose = 5.6 mmol/L

Exclusion Criteria:

• (Undiagnosed) Diabetes - but not impaired fasting glucose (IFG) and/or impaired glucose tolerance (IGT) as evaluated by an oral glucose tolerance test at screening

• Active hearth disease, i.e. history of myocardial infarction, stroke or angina pectoris

• Active or a history of thyroid disease

• Cancer or other malignancies in the past 5 years

• Two sided ovariectomy

• Drug use knowing to interfere with objectives of the study

• oral corticosteroids, lipid-lowering drugs (statins)

• anti-conceptive use (such as the pill or IUD)

• hormone replacement therapy

• long-term antibiotics use

• Habitual intake of soy foods (>1 soy food per week)

• Isoflavone supplements

• Vegetarian

• Following, or have recently followed a (weight-loss) diet

• Allergic to soy or dairy products

• Smoking

• Consuming more than 14 glasses of alcohol per week

• Donated or intended to donate blood 2 months before till two months after the study

• Participation in another biomedical study within 1 month before the first screening visit

• Not willing to be informed if deviations are found in blood samples

• Contraindications to MRI scanning

Study Design

Allocation: Randomized, Endpoint Classification: Efficacy Study, Intervention Model: Crossover Assignment, Masking: Single Blind (Investigator), Primary Purpose: Prevention

Related Conditions & MeSH terms

• Metabolic Syndrome X
• Syndrome

Intervention

Other:
• Soy protein diet
4 weeks high protein diet (20 en%) with 25gr of soy protein per day
• Control diet
4 weeks high mixed protein diet (20 en%)

Locations

Country	Name	City	State
Netherlands	Wageningen University	Wageningen

Sponsors (2)

Lead Sponsor	Collaborator
Wageningen University	Alpro Foundation

Country where clinical trial is conducted

Netherlands, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Insulin sensitivity	Insulin sensitivity is measured with an intravenous glucose tolerance test (IVGTT).	4 weeks	No
Secondary	Adipose tissue gene expression	Adipose tissue samples will be collected for subsequent gene expression analysis.	4 weeks	No
Secondary	Blood lipids	Circulating triglycerides, free fatty acids (FFA), and HDL and total cholesterol will be measured in fasted blood samples, LDL will be calculated.	4 weeks	No
Secondary	Inflammation markers and adipokines	For low-grade inflammation interleukins, tumor necrosis factor-a, C-reactive protein and adipokines will be measured in fasting blood samples. Furthermore, peripheral blood mononuclear cells (PBMC's) will be collected to measure expression of genes involved in lipid handling and inflammation.	4 weeks	No
Secondary	Cardio-metabolic risk factors	Blood pressure and macro vascular regional arterial stiffness will be assessed by Pulse Wave Analysis (PWA). Besides PWA, we will also measure markers for endothelial function in fasting blood samples.	4 weeks	No
Secondary	Hepatic lipid content	Hepatic lipid content The lipid content in liver will be quantified by proton magnetic resonance spectroscopy (1H -MRS)	4 weeks	No