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

Study Overview
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Brief Summary
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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.

Detailed Description
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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.

Official Title
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Investigating the Effects of Probiotic Yogurt on Reducing the Levels of Environmental Toxins Among School Children in Mwanza, Tanzania

Conditions
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C535854, D004786

Intervention / Treatment
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* Dietary Supplement: Pasteurized Whole Milk
* Dietary Supplement: Lactobacillus rhamnosus GR-1


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Aged 6-10 Attends Lake Primary School (Mwanza, Tanzania) Exclusion Criteria: Allergic to milk/ milk products Lactose intolerant

Ages Eligible for Study
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Minimum Age: 6 Years
Maximum Age: 10 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Design Details

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


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Probiotic<br>Daily consumption of yogurt supplemented with L. rhamnosus GR-1 at  10^10 CFU/day | Dietary Supplement: Lactobacillus rhamnosus GR-1<br> <br> * Other names: L. rhamnosus ATCC 55826;|
| Other: Milk<br>Daily consumption of pasteurized whole milk | Dietary Supplement: Pasteurized Whole Milk<br> <br> |

What is the study measuring?
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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. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Metals, Pesticides, Toxicity