Trial Review

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Trial registered on ANZCTR


Registration number
ACTRN12612000806864
Ethics application status
Approved
Date submitted
30/07/2012
Date registered
1/08/2012
Date last updated
14/07/2017
Type of registration
Prospectively registered

Titles & IDs
Public title
Pilot study to assess the effect of Brazil nuts on plasma selenium levels
Scientific title
Pilot study to assess the effect of Brazil nuts on plasma selenium levels in four healthy participants over 25 years of age
Secondary ID [1] 280928 0
nil
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
bowel cancer 287019 0
Condition category
Condition code
Cancer 287349 287349 0 0
Bowel - Back passage (rectum) or large bowel (colon)

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Participants will take 6 brazil nuts a day for four weeks.
This four week intervention will be preceded by a 4 week run-in / wash out phase
participants will be advised to exclude any selenium rich foods or green tea during the study

This Pilot study will confirm the amount of Brazil Nuts we will use in the study comparing with green tea. This follow up study (Effects of combining Selenium (Se) and green tea on biomarkers for colorectal cancer prevention in human subjects). will be registered with ANZCTR in the near future'

At the initial interview dietary advice will be given. This will give an understanding of the nature of the volunteers diet and the likely influence of Se to the diet and suitability to become involved in the study
(if intolerant to nuts volunteers will not participate in the study)
We will ask participants not to consume, whenever possible, throughout the study:-
Any selenium supplement
Any selenium enriched foods, such as nuts, sea food (such as tuna or octopus)

The Brazil nut is a large nut that comes from the castanheiro de para tree in Brazil's rainforests. Each serving of about six to eight nuts contains 4 g of protein and 7 grams each of monosaturated and polysaturated fat.
Brazil nuts (Berholletia excelas, family Lecythidaceae) are the richest known food source of selenium, with mean concentrations reported in the literature between 8-83 micrograms Se/g
6 Brazil nuts daily provides 48 micrograms Se/day - 53 micrograms Se/day
Intervention code [1] 285361 0
Prevention
Comparator / control treatment
not applicable
Control group
Uncontrolled

Outcomes
Primary outcome [1] 287420 0
If supplementation of 6 Brazil nuts/day increases plasma Selenium (Se) levels

A blood sample (5mls of whole blood taken on 2 occasions) will be collected at baseline and after intervention, testing for plasma Selenium levels
Timepoint [1] 287420 0
Blood samples collected at commencement of intervention (week 0) and at end of intervention (wk 4)
Secondary outcome [1] 298108 0
The results generated from this pilot study will help determine if 6 Brazil nuts daily is feasible for human consumption, and if this dose of Brazil nuts significanly increases plasma Se levels.
If so, we will conduct the human intenvention study to determine if a combination of Brazil nuts with green tea extract will benefit human health, including colon cancer
prevention.

To assess the results of the Selenium levels after taking the 6 brazil nuts during the intervention period
Timepoint [1] 298108 0
4 weeks

Eligibility
Key inclusion criteria
Healthy, with no active bowel disease, or
With no previous history of adenoma removal
With plasma Se at or below 106 micro g/dL. (to ensure that people with a high background Se status for whatever reason are not included in the study)
Minimum age
25 Years
Maximum age
65 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
Evidence of any active mucosal bowel disease, eg colitis, or of malabsorption
Previous bowel surgery (excluding polypectomy)
Any allergy or intolerance to nuts

Study design
Purpose of the study
Prevention
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Allocation not concealed
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Single group
Other design features
Phase
Not Applicable
Type of endpoint/s
Safety
Statistical methods / analysis

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
6/08/2012
Actual
16/08/2012
Date of last participant enrolment
Anticipated
13/09/2012
Actual
13/09/2012
Date of last data collection
Anticipated
Actual
Sample size
Target
4
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
SA

Funding & Sponsors
Funding source category [1] 285533 0
Government body
Name [1] 285533 0
National Health and Medical Research Council
Country [1] 285533 0
Australia
Primary sponsor type
Hospital
Name
Flinders Medical Centre
Address
1 Flinders Drive
Bedford Park
5042
South Australia
Country
Australia
Secondary sponsor category [1] 284375 0
None
Name [1] 284375 0
Address [1] 284375 0
Country [1] 284375 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 287555 0
Southern Adelaide Clinical Human Research Ethics Committee.
Ethics committee address [1] 287555 0
Flinders Medical Centre,
Flinders Drive
Bedford Park
SA 5042
Ethics committee country [1] 287555 0
Australia
Date submitted for ethics approval [1] 287555 0
20/06/2012
Approval date [1] 287555 0
17/07/2012
Ethics approval number [1] 287555 0
1/12/0278

Summary
Brief summary
Selenium (Se) - an essential trace micronutrient, and green tea - the most common beverage consumed worldwide, have numerous biological properties that may protect against various cancers, including colorectal cancer (CRC). Despite promising results in preclinical settings, current clinical trial data are not convincing enough to allow general recommendation for using Se or green tea as an effective agent for chemoprevention of cancer in humans.

This is a pilot study on the possible effects of Selenium (Se) in preventing bowel cancer in healthy individuals. 3 or 4 of our staff members will take part in this trial, prior to the launch of a full study once results have been gathered from this pilot study.

Who is it for?

This pilot study on Brazil nuts will be performed on 3 or 4 of our staff. They will take 6 Brazil nuts daily (which will provide 48 micrograms Se/day) for 4 weeks. Their blood samples (on 2 occasions) will be collected at the baseline and after intervention. We believe this pilot study will provide important information as to how many Brazil nuts will be required per day to increase plasma Se levels, as we expand the research into an upcoming, full study.

Background Information

There is growing evidence that a combination of dietary agents may synergistically or additively improve the chemopreventive efficacy than any single dietary agent. Our previous studies in mouse CRC model have shown that Se activate apoptosis (Cancer Res. 2008 June 15;68(12):4938-44), whereas green tea up-regulates DNA repair enzyme. Our recent animal studies have further shown that combining Se and green tea is more effective in suppressing colorectal oncogenesis than either Se or green tea alone, and is associated with regulation of genetic and epigenetic biomarkers implicated in colonic carcinogenesis (submitted to Clinical Cancer Research).

Se and green tea are particularly interesting as a combination not only because they can be co-administered in the diet but also because they have potentially complementary mechanisms of action. We now plan to expand our study to human subjects and determine if a combination dietary supplementation of Se and green tea provides greater health benefits than can be achieved from a single dietary agent of Se or green tea by regulating molecular biomarkers.

We have used selenium-enriched milk protein as the Se source in our previous human trials (Br J Nutr 2011 Aug;106(4):572-82). It was our intention to continue using dairy Se product for our upcoming human trial. Unfortunately, the production and supply of selenium-enriched milk protein has been stopped by Tatura Milk Industries (VIC, Australia). We have to seek an alternative Se source from food, and have decided to use Brazil nuts because it is the richest known food source of Se. A previous randomized controlled human trial has shown that 2 Brazil nuts per day (provided 53micrograms Se/day) is as effective for increasing plasma Se status as 100 micrograms Seasselenomethionine during 12 weeks of intervention, reaching maximum plasma Se levels at 6 weeks (Am J ClinNutr 2008;87:379-3840). Se concentration in Brazil nuts (supplied from Charlesworth, Australia) has recently been analysed by National Measurement Institute (Australia Government, VIC), the average Se concentration in Brazil nuts is relatively low (2.7 micrograms Se/g) compared to that of the report by Thomson et al, where the Se concentration is 6.4 micrograms Se/g (Am J ClinNutr 2008;87:379-3840).
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 34367 0
Prof Graeme Young
Address 34367 0
Flinders Centre for Innovation in Cancer
Flinders University
Bedford Park SA
Country 34367 0
Australia
Phone 34367 0
+61 8 8404 2841
Fax 34367 0
Email 34367 0
[email protected]
Contact person for public queries
Name 17614 0
Prof Jane Upton
Address 17614 0
Department of Gastroenterology
Flinders Medical Centre
1 Flinders Drive
Bedford Park
SA 5042
Country 17614 0
Australia
Phone 17614 0
+61 8 82046071
Fax 17614 0
61 8 82046330
Email 17614 0
[email protected]
Contact person for scientific queries
Name 8542 0
Dr Dr Ying HU
Address 8542 0
Department of Gastroenterology
Flinders Medical Centre
1 Flinders Drive
Bedford Park
SA 5042
Country 8542 0
Australia
Phone 8542 0
+61 8 82045170
Fax 8542 0
Email 8542 0
[email protected]

No information has been provided regarding IPD availability


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

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