Methylation of the PPARg Promoter Region in Pregnancy

Methylation Evaluation of the PPARg Promoter Region (-351 to -260) in Pregnancy

The main objective of this study was to assess whether clinical, anthropometric, and biochemical variables of the mother were associated with changes in the methylation of the PPARg promoter region (-351 to -260). Methodology: This was a matched cohort study with two groups: a) normal weight (NW) pregnant women (n = 21) and their offspring, and b) overweight (OW) pregnant women (n = 20) and their offspring. DNA was extracted from leukocytes (4000-10,000 cells) in the MagnaPure (Roche) using the MagNAPure LC DNA Isolation Kit 1 (Roche, Germany). The treatment of DNA (2 µg) was performed with sodium bisulfite (EZ DNA Methylation-Direct Kit, ZymoResearch). Real-time polymerase chain reaction (qPCR) was performed in a LightCycler 2.0 (Roche) using the SYBR® Advantage® qPCR Premix Kit (Clontech).

Study Overview

• Status: Completed
• Conditions: Body Weight

Detailed Description

Women were recruited in the first trimester of pregnancy not including cases with congenital heart and disabling or autoimmune diseases. Those whose clinical follow-up were lost or, if in the postpartum period, who had to be attended in the obstetric intensive care unit were eliminated from the study.

A clinical visit per month was established. Body weight and height were measured in an overnight fasting status using an adult scale (Seca, Hamburg, Germany). Prepregnancy Body Mass Index (BMI) was calculated as weight in kg divided by height in meters squared based on the prenatal chart or on the self-reported weight of women with no prenatal chart.

Blood pressure was recorded at each visit using a standard sphygmomanometer (Riester Big Ben® Square, Germany). Preeclampsia was diagnosed and classified according to the American College of Obstetricians and Gynecologists (ACOG).

Fasting blood samples (10 ml) were taken at the HMPMP laboratory in an early morning after an overnight fasting. Serum samples were analyzed for glucose and lipid profile (Dimension Rx L Max, Dade Behring, USA). At the end of pregnancy, 1 to 2 ml of neonatal peripheral blood sample for leukocyte DNA extraction was taken.

Dietetic treatment was calculated according to height, weeks of gestation, and weight, considering an energy intake of 30 kcal/kg of ideal weight and a macronutrient distribution of: 55-65% carbohydrates, 10-20% fat, and the remainder as proteins. On each nutritional visit, the Healthy Eating Index for Pregnancy (HEI) was evaluated, and all women were recommended to include methionine-rich foods (beans, eggs, fish, garlic, lentils, onion, and soy) and those containing folic acid and vitamin B12 (beef liver, cereals, whole grains, yeast, etc.) in adequate quantities in their diet. The information was complemented with the Food Frequency Questionnaire (FFQ), and the diet adherence was considered adequate with 80% compliance to the indicated calories, at least in four visits.

This project had no risk to pregnant women and their infants, according to the regulations of the General Health Research Law of Mexico. We followed the Declaration of Helsinki, and all patients were asked to sign the written informed consent.

• Study Type: Observational
• Enrollment (Actual): 41

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 42 years (Adult)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: Female

• Sampling Method: Non-Probability Sample

Study Population

Pregnant women attended at the Maternal-Perinatal Hospital "Mónica Pretelini Sáenz".

Description

Inclusion Criteria: Women attended in the first trimester of pregnancy -

Exclusion Criteria: congenital heart and disabling or autoimmune diseases

-

Study Plan

How is the study designed?

Number of groups / cohorts

2

Cohorts and Interventions

Group / Cohort
Normal weight (NW) pregnant women; Pregnant women with Body Mass Index (BMI) > = 30. Body weight and height were measured in an overnight fasting status using an adult scale (Seca, Hamburg, Germany). Prepregnancy BMI was calculated as weight in kg divided by height in meters squared based on the prenatal chart or on the self-reported weight of women with no prenatal chart. Dietetic treatment was calculated according to height, weeks of gestation, and weight, considering an energy intake of 30 kcal/kg of ideal weight and a macronutrient distribution of: 55-65% carbohydrates, 10-20% fat, and the remainder as proteins.
Overweight (OW) pregnant women; Pregnant women with Body Mass Index (BMI) < 30. Body weight and height were measured in an overnight fasting status using an adult scale (Seca, Hamburg, Germany). Prepregnancy BMI was calculated as weight in kg divided by height in meters squared based on the prenatal chart or on the self-reported weight of women with no prenatal chart. Dietetic treatment was calculated according to height, weeks of gestation, and weight, considering an energy intake of 30 kcal/kg of ideal weight and a macronutrient distribution of: 55-65% carbohydrates, 10-20% fat, and the remainder as proteins.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Evidence of the effect of Body Mass Index (BMI) on the methylation status of the PPAR gamma promoter region (-351 to -260).	The treatment of DNA (2 µg) was performed with sodium bisulfite (EZ DNA Methylation-Direct Kit, ZymoResearch). For the control group, we used purified human methylated and unmethylated DNA (Zymo Research) with specific oligonucleotides. Lymphocyte DNA from healthy donors was used as negative control, and methylated DNA "in vitro" with Sss I enzyme (New England Biolabs) was used as positive control for methylation. The methylated (M3) and unmethylated (U3) primers used were those proposed by Pancione et al.	Pregnant women were followed until delivery.

Collaborators and Investigators

• Sponsor: Materno-Perinatal Hospital of the State of Mexico
• Investigators: Principal Investigator: Hugo Mendieta Zerón, PhD., Asociación Científica Latina A.C.

Study record dates

Study Major Dates

• Study Start: September 1, 2009
• Primary Completion (Actual): August 1, 2010
• Study Completion (Actual): March 1, 2011

Study Registration Dates

• First Submitted: March 11, 2015
• First Submitted That Met QC Criteria: March 17, 2015
• First Posted (Estimate): March 24, 2015

Study Record Updates

• Last Update Posted (Estimate): March 24, 2015
• Last Update Submitted That Met QC Criteria: March 17, 2015
• Last Verified: March 1, 2015

More Information

Terms related to this study

• Keywords: body mass index; pregnancy; PPAR gamma; methylation
• Additional Relevant MeSH Terms: Body Weight
• Other Study ID Numbers: 05-06-2009