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Effects of a High-CML Diet on Absorption and Excretion Levels in Healthy Adults

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ClinicalTrials.gov Identifier: NCT03208946
Recruitment Status : Recruiting
First Posted : July 6, 2017
Last Update Posted : July 12, 2017
Sponsor:
Information provided by (Responsible Party):

Study Description
Brief Summary:

The aim of this study is to evaluate the effect of carboxymethyl-lysine (CML) on the levels of absorption and excretion of CML, and in the microbiota of healthy adults. To achieve the objective, a randomized clinical trial will be carried out. Before the intervention, subjects will have a washout period for seven days, then they will be randomly assigned to either a high-CML or to a low-CML diet for 5 days. Both groups will consume the foods provided by the researchers at the research center. Diets for this intervention will be based on an isocaloric diet that will include breakfast, lunch, snacks and dinner.

Blood samples will be taken the first day, the second day of the intervention, and after the five days of the intervention. Urine and fecal samples will be taken the day before the intervention and after the intervention. CML levels will be measured by Liquid chromatography tandem-mass spectrometry in serum and urine samples to evaluate the levels of absorption and excretion. DNA extraction from the fecal sample will be carried out by a commercial kit. Bacterial log10 number of copies will be determined by using q-PCR.


Condition or disease Intervention/treatment
Healthy Other: High-CML diet Other: Low-CML diet

Detailed Description:

Advanced glycation end products (AGEs) are a heterogenous group of compounds form mainly by the Maillard reaction. AGEs can be found endogenously and in some foods. Several AGEs have been characterized, but carboxymethyl-lysine (CML) is one of the most widely studied in foods. Several studies have demonstrated the association between advanced glycation end products and several pathologies. However, few studies have focused on studying the absorption and excretion processes of these glycation products. Therefore, the objective of the study is to evaluate the effect of carboxymethyl-lysine (CML) on the levels of absorption and excretion of CML, and in the microbiota of healthy adults. To achieve the objective, a randomized clinical trial will be carried out, which will consist of a 7-day washout period during which participants will receive general recommendations that allow them to stick to a diet with a low CML content, adherence to these recommendations will be evaluated through three dietary records. At the end of the washing period, participants will be randomly assigned to either a high-CML or to a low-CML diet for 5 days. Participants will receive the 5 corresponding meals (breakfast, lunch, snacks and dinner) during the 5 days of the intervention, these preparations will be elaborated by a catering company with indications and supervision by the research group. Participants will assist to the research center to receive the breakfast, lunch and snacks. After lunch the subjects will receive a package containing a snack for mid-evening and the dinner. Adherence to the diet during the intervention period will be evaluated through a dietary record of foods.

The intervention will be based on an isocaloric diet with a distribution of 55 to 63% carbohydrates, 12 to 15% protein, 25 to 30% lipids and less than 10% saturated fat.

The diet with high content of CML will have twice the amount that the low diet, but with similar amounts of macro and micronutrients.

A blood sample will be taken on the first day of the intervention to measure CML basal levels. In order to evaluate the levels of CML absorption, the serum collection will be performed on the second day and at the end of the intervention. To evaluate the levels of CML excretion 24-hours urine will be collected the day before the intervention and the day after the dietary intervention finished. To evaluate the effects on the microbiota subjects will take a fecal sample the day before and a day after the intervention. Measurement of CML in serum, 24-hour urine and food will be performed by Liquid chromatography tandem-mass spectrometry. DNA extraction from the fecal sample will be carried out by a commercial kit. Bacterial log10 number of copies will be determined by using q-PCR.


Study Design

Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 30 participants
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)
Primary Purpose: Basic Science
Official Title: Effects of a High Carboxymethyl-lysine (CML) Diet on Absorption and Excretion Levels in Healthy Adults
Actual Study Start Date : July 6, 2017
Estimated Primary Completion Date : December 10, 2017
Estimated Study Completion Date : February 15, 2018
Arms and Interventions

Arm Intervention/treatment
Experimental: High-CML diet
An isocaloric, high-CML content diet with a distribution of 55 to 63% carbohydrates, 12 to 15% protein, 25 to 30% lipids and less than 10% saturated fat.
Other: High-CML diet
Participants will be randomly assigned to either a high-CML or to a low-CML diet for 5 days, and they will receive the 5 corresponding meals (breakfast, lunch, snacks and dinner) during the 5 days of the intervention. These preparations will be elaborated by a catering company with indications and supervision by the research group. The intervention will be based on an isocaloric diet with a distribution of 55 to 63% carbohydrates, 12 to 15% protein, 25 to 30% lipids and less than 10% saturated fat and it macro and micronutrients will be similar in both diets. The only difference will be the CML content.
Sham Comparator: Low-CML diet
An isocaloric, low-CML content diet with a distribution of 55 to 63% carbohydrates, 12 to 15% protein, 25 to 30% lipids and less than 10% saturated fat.
Other: Low-CML diet
Participants will be randomly assigned to either a high-CML or to a low-CML diet for 5 days, and they will receive the 5 corresponding meals (breakfast, lunch, snacks and dinner) during the 5 days of the intervention. These preparations will be elaborated by a catering company with indications and supervision by the research group. The intervention will be based on an isocaloric diet with a distribution of 55 to 63% carbohydrates, 12 to 15% protein, 25 to 30% lipids and less than 10% saturated fat and it macro and micronutrients will be similar in both diets. The only difference will be the CML content.


Outcome Measures

Primary Outcome Measures :
  1. Serum levels of Carboxymethyl-lysine [ Time Frame: six days ]
    Changes in serum levels of Carboxymethyl-lysine, a marker of AGEs, will be measured. Carboxymethyl-lysine serum levels will be measured by Liquid chromatography tandem-mass spectrometry.

  2. Urinary levels of Carboxymethyl-lysine [ Time Frame: six days ]
    Changes in urinary levels of Carboxymethyl-lysine, a marker of AGEs, will be measured. Carboxymethyl-lysine urinary levels will be measured by Liquid chromatography tandem-mass spectrometry.


Secondary Outcome Measures :
  1. Bacterial log10 number of copies in fecal samples [ Time Frame: six days ]
    Changes in bacterial log10 number of copies in fecal sample will be measured by qPCR.


Eligibility Criteria

Information from the National Library of Medicine

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Ages Eligible for Study:   19 Years to 35 Years   (Adult)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   Yes
Criteria

Inclusion Criteria:

  • Adults 19 to 35 years old.
  • Subjects with a body mass index (BMI) of 18.5 - 25 kg / m2
  • Clinically healthy subjects, without presenting chronic diseases: diabetes mellitus, renal or cardiovascular disease.
  • Non-smoking subjects.
  • Subjects with low alcohol consumption.
  • Subjects that do not consume food supplements.
  • Subjects without known food allergies.
  • Subjects without lactose intolerance or other foods.
  • Subjects without gastrointestinal problems.
  • Subjects who do not practice 150 minutes or more a week of physical exercise

Exclusion Criteria:

  • Subjects with less than 80% adherence to the diet.
  • Subjects who do not collect their indicated urine samples.
  • Subjects presenting with an allergy, or adverse event during the intervention.
Contacts and Locations

Information from the National Library of Medicine

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.

Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03208946


Contacts
Contact: Claudia Luevano Contreras, PhD 524772674900 ext 4679 claudialc11@gmail.com
Contact: Ma. Eugenia Garay-Sevilla, MD marugaray_2000@yahoo.com

Locations
Mexico
University of Guanajuato Recruiting
León, Guanajuato, Mexico, 37320
Contact: Claudia Luevano Contreras, PhD    524772496700    claudialc11@gmail.com   
Contact: Ma. Eugenia Garay-Sevilla, MD         
Sponsors and Collaborators
Universidad de Guanajuato
Investigators
Principal Investigator: CLAUDIA LUEVANO CONTRERAS, PhD Universidad de Guanajuato
Principal Investigator: Ma. Eugenia Garay-Sevilla, MD Universidad de Guanajuato
More Information

Responsible Party: Claudia Luévano-Contreras, Associate Professor, Universidad de Guanajuato
ClinicalTrials.gov Identifier: NCT03208946     History of Changes
Other Study ID Numbers: CIBIUG-P32-2016
First Posted: July 6, 2017    Key Record Dates
Last Update Posted: July 12, 2017
Last Verified: July 2017
Individual Participant Data (IPD) Sharing Statement:
Plan to Share IPD: No

Studies a U.S. FDA-regulated Drug Product: No
Studies a U.S. FDA-regulated Device Product: No

Keywords provided by Claudia Luévano-Contreras, Universidad de Guanajuato:
Advanced glycation end products
Absorption
Excretion