Investigating the Effects of Probiotic Yogurt on Reducing the Levels of Environmental Toxins Among School Children in Mwanza, Tanzania (PDTX)

The primary objective of this pilot study is to determine if consumption of a probiotic yogurt causes reduced levels of environmental toxins in a group of school-aged Tanzanian children. The secondary objective is to determine the levels of environmental toxins in Tanzanian children and compare these to literature values of levels believed to negatively affect health and development. The third objective is to analyze the intestinal microbiota of the children and to determine if consumption of a probiotic yogurt has a significant affect on the microbiota composition.

Study Overview

• Status: Completed
• Conditions: C535854; D004786
• Intervention / Treatment: Dietary supplement: Lactobacillus rhamnosus GR-1; Dietary supplement: Pasteurized Whole Milk

Detailed Description

A group of 60 first year students from the Lake Primary School will be recruited for inclusion into the study. After gaining consent from the child's caregiver, each child will be given a participant number and blood, urine and fecal samples will be collected from each child by qualified personnel from NIMR. Children will be randomized into two groups (n=30) to match age, sex and weight, one of which will receive a 100 g probiotic yogurt containing Lactobacillus rhamnosus GR-1 while the other group will receive an equivalent portion of milk. After 30 days of consuming the yogurt or milk, samples will again be collected.

Samples will be shipped back to London, Ontario Canada on dry ice for analysis. Blood and urine will be analyzed via high-resolution sector field inductively coupled plasma mass spectrometry (HR-SF-ICP-MS) to determine levels of toxic heavy metals (Mercury, Lead, Cadmium, Arsenic). This will be carried out by the London Health Sciences Trace Elements laboratory in Canada. Urine will also be analyzed via gas chromatography/ mass spectrometry (GC-MS) to determine levels of pesticides at the Biotron Facility (University of Western Ontario). We will also examine urine via NMR for potential host metabolic changes in response to probiotic instillation.

Bacterial community DNA samples will be extracted and analyzed to determine the gastrointestinal microbiota of the children both before and after administration of the probiotic yogurt to determine the effect of the yogurt on the gut microbiome. Briefly, DNA will be extracted with the Qiagen Stool DNA extraction kit and bacterial community 16S rRNA genes will amplified using barcoded primers specific for a variable region within the gene. The samples will be pooled and sequenced on the Ion Torrent platform (London Regional Genomics Center, Canada). Reads are then processed and analyzed using custom scripts as well as the Quantitative Insights Into Microbial Ecology (QIIME) tool, which is the leading package for microbiota analysis.

• Study Type: Interventional
• Enrollment (Actual): 44
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Tanzania
  • Mwanza, Tanzania
    • National Institute for Medical Research

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 6 years to 10 years (Child)
• Accepts Healthy Volunteers: Yes
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Aged 6-10
• Attends Lake Primary School (Mwanza, Tanzania)

Exclusion Criteria:

• Allergic to milk/ milk products
• Lactose intolerant

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Probiotic; Daily consumption of yogurt supplemented with L. rhamnosus GR-1 at ~10^10 CFU/day	Dietary supplement: Lactobacillus rhamnosus GR-1; Other Names: L. rhamnosus ATCC 55826
Other: Milk; Daily consumption of pasteurized whole milk	Dietary supplement: Pasteurized Whole Milk

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in Body Toxin Levels	Body toxin levels (metals, pesticides) by HR-SF-ICP-MS and GC/MS.	Before and after the 25 day intervention period.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Changes in Microbiota Composition	Stool microbiota composition shifts as determined by 16S rRNA profiling.	Before and after the 25 day intervention period.
Microbes linked to host toxin levels	Microbes, as determined via 16S rRNA sequencing, associated with high toxin levels.	Initial sample collection visit
Changes in host metabolism due to probiotic instillation	Host metabolic shifts as measured by NMR from urine	Before and after the 25 day intervention period.

Collaborators and Investigators

• Sponsor: Western University, Canada
• Collaborators: National Institute for Medical Research, Tanzania

Publications and helpful links

General Publications

• Bisanz JE, Enos MK, Mwanga JR, Changalucha J, Burton JP, Gloor GB, Reid G. Randomized open-label pilot study of the influence of probiotics and the gut microbiome on toxic metal levels in Tanzanian pregnant women and school children. mBio. 2014 Oct 7;5(5):e01580-14. doi: 10.1128/mBio.01580-14.

Study record dates

Study Major Dates

• Study Start: December 1, 2012
• Primary Completion (Actual): December 1, 2012
• Study Completion (Actual): August 1, 2013

Study Registration Dates

• First Submitted: July 4, 2013
• First Submitted That Met QC Criteria: July 17, 2013
• First Posted (Estimate): July 22, 2013

Study Record Updates

• Last Update Posted (Estimate): December 17, 2013
• Last Update Submitted That Met QC Criteria: December 16, 2013
• Last Verified: December 1, 2013

More Information

Terms related to this study

• Keywords: Pesticides; Toxicity; Metals
• Other Study ID Numbers: 102881