Healthy
Conditions
Keywords
Healthy, Colon
Brief summary
Colorectal (CRC) cancer is the third most common cancer in the United States and its incidence is rising in younger populations. Diet seems to affect risk for CRC. Many parts of our diet are processed and modified by the microbes or bacteria in our gut. There are many different types of bacteria in our gut, each one of us has a community of different types and amounts of each type. When we eat flaxseeds, certain types of bacteria will process them - producing compounds that can then affect our body. How much of these compounds are produced by each person depends on the community of bacteria in the gut. Flaxseed and in certain nuts contain lignans, compounds that may have health benefits. Gut bacteria can convert the lignans into biologically active compounds that in animal models prevent the development of colon cancer. The investigators will study how these biologically active compounds affect colon cell-signaling pathways important to colorectal cancer risk. Results from our study will bridge the current knowledge from animal studies and epidemiologic studies and may help to inform approaches for future CRC prevention.
Detailed description
Part 1 (Screening): Potential participants submit a screening questionnaire for eligibility. Eligible participants will come for an orientation for Part 1. If they consent the study coordinator will measure their height and weight and give them all the materials to do the activities for Part 1. 1. Stool sample 2. Days 1-3: take a lignan pill for three days 3. Day 3: 24-hour urine collection. No all participants will be eligible for Part 2. Part 2 (Trial): Eligible participants will come for an orientation and consent. Activities: 1. 3-day food record 2. Stool sample 3. Fasting blood draw. 4. Colon cleanse (at home). 2 months- no study activities Period 1, 1\. Day 0: Stool sample 2. Day 0: 24-h urine collection 3. Take study capsule daily for 2 months. 4. Day 54: Stool sample 5. Day 54: 24-hour urine 6. Day 55: Fasting blood draw 7. Day 60 Sigmoidoscopy with biopsies 2 months- no study activities Period 2 1. Day 0: Stool sample 2. Day 0: 24-h urine collection 3. Take the other study capsule daily for 2 months. 4. Day 54: Stool sample 5. Day 54: 24-hour urine 6. Day 55: Fasting blood draw 7. Day 60 Sigmoidoscopy with biopsies
Interventions
DIETARY_SUPPLEMENTFlaxseed Lignans
We will use a specially formulated dietary lignan supplement (Lignan Research Inc., San Diego, CA) as a source of lignans for the lignan challenge in the screening study and as a daily supplement in the intervention. It is a flaxseed extract that contains SDG (269 mg/g; 50 mg/capsule), pinoresinol diglucoside (160 mg/g), and lesser amounts of caffeic (50 mg/g), ferulic (40 mg/g) and coumaric acids (30 mg/g). Lignan capsules and placebo capsules will be prepared by Lignan Research, Inc., a well-established supplement company that follows GMP.
Sponsors
Texas A&M University
National Cancer Institute (NCI)
Fred Hutchinson Cancer Center
Study design
Allocation
RANDOMIZED
Intervention model
CROSSOVER
Primary purpose
OTHER
Masking
TRIPLE (Subject, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
20 Years to 45 Years
Healthy volunteers
Yes
Inclusion criteria
* healthy * non-smoking men and women * ages 20-45 y * don't eat a lot of vegetables
Exclusion criteria
* chronic medical illness, history of gastrointestinal disorders (e.g., ulcerative colitis, Crohn disease, celiac sprue, HNPCC, familial adenomatous polyposis, pancreatic disease, previous gastrointestinal resection, radiation or chemotherapy) and cancer (other than non-melanoma skin cancer); * pregnancy or lactation; * weight change greater than 4.5 kg within past year; * oral or IV antibiotic use within the past 3 months; * alcohol intake of \>2 drinks/day (2 drinks being equivalent to 720 ml beer, 240 ml wine, or 90 ml spirits); * dietary fiber intake \>15 g/day; * abnormal renal, liver or metabolic test results at baseline; * inability to swallow pills; * contraindications to sigmoidoscopy; * regular use of prescription or over-the-counter medications, including oral contraceptives; * known allergy to nuts, seeds and flaxseed; * intention to relocate out of study area within next 12 months.
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| mRNA expression in colonic mucosal tissue (stroma and epithelial) and exfoliated cells in individuals with low- or high-ENL excretion. | 60 days |
Countries
United States
Outcome results
None listed