Cystatin SN Binds to Phytic Acid and Predicts Non-heme Iron Bioavailability

NCT03030703 | Completed

• 1 other identifier: SPPhyticAcidTrial
• Study Type: interventional
• Target: 7
• Locations: 1 country
• Sites: 1

Brief Summary

Phytic acid is a known inhibitor of iron bioavailability, although long term studies have suggested possibly exaggerated findings compared to single meal studies, pointing to phytic acid adaptation over time. Salivary proline-rich proteins have been found to reduce tannin-iron chelation, but studies have not explored changes in salivary proteins that may result in phytic acid adaptation. The primary objectives of this study are: 1) To determine whether phytic acid impacts iron bioavailability or status when consumed over time 2) to test whether salivary protein production may impact iron bioavailability with phytic acid supplementation, and 3) to explore in vitro phytic acid salivary binding. Secondary objectives included assessment of the reliability of astringency as a measure of salivary protein production and iron absorption. The study was conducted in an iron absorption study of 7 women, aged 18-35 years old, to determine iron bioavailability with supplementation of 350 mg phytic acid before and after regular, three times daily supplementation for four weeks. Direct iron absorption was measured using area under the curve. Iron status was measured by changes in hemoglobin and ferritin, and was adjusted by participant c-reactive protein levels. Salivary samples were collected before and after supplement consumption during meal challenges, and analyzed on HPLC and by ELISA. Astringency testing was conducted at the end of each meal challenge. In vitro saliva-phytic acid modeling was explored on HPLC, MALDI-TOF, and ELISA. Iron absorption and status markers were analyzed by ANOVA, and mixed-modeling followed by pairwise comparison by least significant differences. Pearson's correlations were used to correlated salivary proteins and astringency with iron bioavailability. The present study will provide important information regarding the approximate influence of phytic acid consumption on iron bioavailability and storage over time in regards to salivary proteins. It will also give context to the role of salivary proteins with phytic acid consumption over time. Data will also help to delineate possible physiological mechanisms underlying phytic acid adaptation and possible ways to detect individuals who better adapt than others.

Conditions

Iron-deficiency; Iron Deficiency Anemia

Keywords

Phytic acid; Cystatin; Salivary proline-rich protein; antinutrient

Outcome Measures

Primary Outcomes (3)

• Change in baseline to endline area under the curve after meal challenge at weeks 0 and 4 of intervention

  Change in area under the curve will be measured after administration of test meal including ferrous sulfate and condensed tannin supplementation at weeks 0 and 4

  Baseline and 4 weeks

• Change in baseline to endline hemoglobin and serum ferritin at weeks 0 and 4 of intervention

  Change in ferritin and hemoglobin will be measured before administration of test meals at weeks 0 and 4

  Baseline and 4 weeks

• Change in salivary proteins at weeks 0 and 4 of intervention

  HPLC determination of salivary proteins will be analyzed from saliva collected before and after test meals at weeks 0 and 4 of the intervention

  Baseline and 4 weeks

Study Arms (1)

350 mg phytic acid

EXPERIMENTAL

350 mg phytic acid (inositol hexaphosphate) at week 0 (before supplementation) and at week 4 (after supplementation)

Dietary Supplement: phytic acid

Interventions

phytic acid DIETARY_SUPPLEMENT

350 mg phytic acid (inositol hexaphosphate) three times daily for four weeks

Also known as: inositol hexaphosphate

350 mg phytic acid

Eligibility Criteria

• Age: 18 Years - 35 Years
• Sex: female
• Healthy Volunteers: Yes
• Age Groups: Adult (18-64)

You may qualify if:

• Female, 18-35 years' old
• Non-obese BMI (18-29.9)
• Signed informed consent

You may not qualify if:

• Oral disease
• Gastrointestinal disease
• Tobacco user
• Heavy alcohol user
• Pregnancy (assessed by pregnancy test)
• Lactation
• Medications affecting iron bioavailability
• Vitamin or mineral supplementation (other than vitamin B12)

Sponsors & Collaborators

• Kansas State University: lead
• United States Department of Agriculture Foreign Agricultural Service: collaborator
• American Academy of Nurse Practitioners: collaborator

Study Sites (1)

Physical Activity and Nutrition Research Consortium

Manhattan, Kansas, 66502, United States

Location

MeSH Terms

Conditions

Anemia, Iron-Deficiency

Interventions

Phytic Acid

Condition Hierarchy (Ancestors)

Anemia, Hypochromic; Anemia; Hematologic Diseases; Hemic and Lymphatic Diseases; Iron Deficiencies; Iron Metabolism Disorders; Metabolic Diseases; Nutritional and Metabolic Diseases

Intervention Hierarchy (Ancestors)

Inositol Phosphates; Inositol; Sugar Alcohols; Alcohols; Organic Chemicals; Carbohydrates; Sugar Phosphates

Study Officials

• Brian L Lindshield, Ph.D.

  Kansas State University

  PRINCIPAL INVESTIGATOR

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: NA
• Masking: NONE
• Purpose: PREVENTION
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Ph.D., Associate Professor

Study Record Dates

• First Submitted: January 23, 2017
• First Posted: January 25, 2017
• Study Start: November 11, 2016
• Primary Completion: December 10, 2016
• Study Completion: December 10, 2016
• Last Updated: January 25, 2017

Record last verified: 2017-01

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)