Liver and Bone Retinol Levels in Guatemalan Adolescents and Adults (GVAS)

June 17, 2020 updated by: Newcastle University

Niveles de Retinol Hepatico y óseo en cadáveres de Adolescentes y Adultos Guatemaltecos (Liver and Bone Retinol Levels in Guatemalan Adolescents and Adults)

Guatemala has enforced mandatory fortification of sugar with vitamin A (VA) since June 1974 and has led to a highly successful reduction in VA deficiency and associated disease. However, Ribaya-Mercado et al. 2014, estimated the biological impact of sugar fortified with retinyl palmitate that there may be a risk of chronic excess intake of preformed VA associated with programs of mass fortification. A recent food consumption survey in two departments in Guatemala found the average daily sugar intake in children under the age of two who aren´t being breastfed is 30.3 g, which translates into a daily intake of 272 μg of retinol (almost the full estimated average requirement (EAR) for that age group). Since data from the second National Survey on Micronutrients suggest a risk of VA toxicity, it is important to determine the levels of hepatic VA directly in corpses of individuals, of all ages, who have died of non-metabolic causes. Due to this, the investigators propose to assess liver and bone VA levels in combination with gene expression, histopathology and biochemical analyses, to elicit indications of hypervitaminosis A in Guatemala.

Study Overview

Detailed Description

Objectives:

  1. To determine the post mortem concentration of hepatic and bone VA in corpses of adolescent, young and elderly adults as an indicator of exposure to dietary VA
  2. To assess the effect of high VA exposure on key enzymes in liver and bone tissue and to assess the risk of hypervitaminosis A in people exposed to compulsory mass vitamin A fortification program in Guatemala.

Methodology:

Setting and sampling The corpses for this study will be obtained from the National Institute of Forensic Sciences' (INACIF) departmental morgues in 2 hospitals in Guatemala City. The study population will be 150 cadavers sampled for VA tissue concentration; gene expression analysis combined with histopathology.

Sample collection process and duration All samples will be collected during necropsies carried out at the INACIF forensic morgue. During necropsy, the liver will be weighed and the information recorded. A range of up to 10 x 3 g samples of the liver's right lobe will be obtained. Each sample will be properly labelled with previously prepared codes. Liver samples for histopathological analysis will be stored in 10% buffered formalin for 24 hours prior to transfer to ethanol before embedding, sectioning and staining. All samples collected for retinoid analysis will be frozen on dry ice in the morgue, transported as such to the laboratory and subsequently stored at -80˚C. Liver samples for gene expression analysis will be collected in RNAlater solution to protect RNA stability and subsequently stored at -80˚C until shipment to Newcastle University. The hepatic VA analysis will be done in Newcastle University using established High Perfromance Liquid Chromatography (HPLC) methods. Samples for analysis of gene expression will be sent on dry ice to Newcastle for RNA extraction and quantification. Since it is possible to obtain good quality RNA suitable for Quantitative Polymerase Chain Reaction (q-PCR) based analyses from post mortem tissue up to 72 hours after death, tissue samples stored in RNAlater within 24 hours of death will be adequate for gene expression analysis. Furthermore, experience from the investigators human biobank in Newcastle shows that tissue RNA can be extracted successfully after the demise of a patient up to 72 hours after death as long as the tissue has a pH of over 6. Gene expression of key regulatory proteins, such as LRAT and CYP26A1 will be performed in Newcastle. Choice of genes was based on the fact that LRAT may become saturated at very high levels of VA, leading to increasing levels of free circulating VA that can be metabolized to retinoic acid and other metabolites via CYP26A. Histopathological analysis will be carried out by pathologists in Guatemala with digitised slides being sent to the pathologist within Newcastle University - these slides will be analysed by both pathologists independently.

Bone samples will also be obtained during the necropsy carried out at the INACIF forensic morgue. The iliac crest bone will be exposed by making an incision and removing the overlying soft tissue (skin, adipose tissue, connective tissue and muscle). The periosteum and cortical bone shall be removed via osteotomy exposing the spongy bone. Biopsy needles will be used to take samples from the spongy bone for analysis of tissue VA concentrations and gene expression, as previously described, at Newcastle University.

All samples will be shipped to Newcastle University on dry ice.

Study duration According to the information provided by INACIF 18 autopsies were performed between March and May 2013 on children less than one year of age, 24 on children from 1 to 4 years old, 11 on children 5 to 9 years old, 51 on individuals from 10 to 14 years old, 281 on adolescents 15 to 19 years old, and 401 on young adults 20 to 24 years old. According to INACIF's forensic doctor, ~60% of the total number of autopsies carried out in Guatemala are performed in the capital city. The main causes of death in children under the age of 9 were head injuries and other types of trauma. Individuals from 10 to 24 years of age died mainly due to violence: firearms, stabbings, choking and different types of trauma.

Study Type

Observational

Enrollment (Anticipated)

150

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Locations

      • Guatemala City, Guatemala, Zona 11
        • Recruiting
        • Hospital Roosevelt
        • Contact:
        • Contact:
        • Principal Investigator:
          • Francisco Chew, MD
        • Sub-Investigator:
          • Keyla Castellanos, MD
      • Guatemala City, Guatemala, Zona 11
        • Recruiting
        • INCAP
        • Contact:
        • Contact:
        • Principal Investigator:
          • Francisco Chew, MD
        • Sub-Investigator:
          • Keyla Castellanos, MD
      • Guatemala City, Guatemala, Zona 1
        • Recruiting
        • Hospital General San Juan de Dios
        • Contact:
        • Contact:
        • Principal Investigator:
          • Francisco Chew, MD
        • Sub-Investigator:
          • Keyla Castellanos, MD
      • Guatemala City, Guatemala, Zona 3
        • Recruiting
        • Morgue del INACIF
        • Contact:
        • Contact:
        • Principal Investigator:
          • Francisco Chew, MD
        • Sub-Investigator:
          • Keyla Castellanos, MD
    • Tyne And Wear
      • Newcastle Upon Tyne, Tyne And Wear, United Kingdom, NE2 4HH
        • Active, not recruiting
        • Newcastle University

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

10 years and older (ADULT, OLDER_ADULT, CHILD)

Accepts Healthy Volunteers

Yes

Genders Eligible for Study

All

Sampling Method

Non-Probability Sample

Study Population

Guatemalan cadavers, from 2 hospitals in Guatemala City, aged >10 years with a non-metabolic cause of death, within 24 hours of death

Description

Inclusion Criteria:

  • Aged >10 years
  • Non-metabolic cause of death (e.g. accidents, trauma, or violence from firearms, stabbings, cranial and other trauma, asphyxiation etc.)
  • No longer than 24 hours since the time of death
  • Lived in Guatemala (exposure to fortified sugar)

Exclusion Criteria:

  • Aged <10 years
  • Individuals with metabolic or nutritional conditions (diabetes, dyslipidemias, chronic alcoholism, etc.)
  • Longer than 24 hours since the time of death
  • Not Guatemalan resident (Tourist, visitor etc.)

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Cohorts and Interventions

Group / Cohort
Adolescents
Individuals aged 10-19 years
Young Adults
Individuals aged 20-39 years
Elderly Adults
Individuals aged 40+ years

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Liver Vitamin A concentration
Time Frame: Enrolment
Liver Vitamin A concentration
Enrolment
Liver Gene Expression
Time Frame: Enrolment
Gene expression associated with Vitamin A
Enrolment
Liver Histology
Time Frame: Enrolment
Histological changes associated with Vitamin A
Enrolment
Bone Gene Expression
Time Frame: Enrolment
Gene expression associated with Vitamin A
Enrolment

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Bone Vitamin A concentration
Time Frame: Enrolment
Bone Vitamin A concentration
Enrolment

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Investigators

  • Principal Investigator: Francisco Chew, MD, Institute of Nutrition of Central America and Panama
  • Principal Investigator: Erick Boy, MD, PhD, HarvestPlus
  • Study Director: Georg Lietz, PhD, Newcastle University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (ACTUAL)

October 24, 2019

Primary Completion (ANTICIPATED)

July 1, 2020

Study Completion (ANTICIPATED)

July 1, 2020

Study Registration Dates

First Submitted

March 23, 2020

First Submitted That Met QC Criteria

June 17, 2020

First Posted (ACTUAL)

June 18, 2020

Study Record Updates

Last Update Posted (ACTUAL)

June 18, 2020

Last Update Submitted That Met QC Criteria

June 17, 2020

Last Verified

February 1, 2020

More Information

Terms related to this study

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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