Effects of Supplemental Calcium and Vitamin D on Circulating Biomarkers of Gut Barrier Function in Patients with Colon Adenoma: A Randomized Clinical Trial.

Gut barrier dysfunction promotes chronic inflammation, contributing to several gastrointestinal diseases, including colorectal cancer. Preliminary evidence suggests that vitamin D and calcium could prevent colorectal carcinogenesis, in part, by influencing gut barrier function. However, relevant human data are scarce. We tested the effects of supplemental calcium (1,200 mg/day) and/or vitamin D3 (1,000 IU/day) on circulating concentrations of biomarkers of gut permeability (anti-flagellin and anti-lipopolysaccharide IgA and IgG, measured via ELISA) from baseline to 1 and 3 or 5 years postbaseline among 175 patients with colorectal adenoma in a randomized, double-blinded, placebo-controlled clinical trial. We also assessed factors associated with baseline concentrations of these biomarkers. We found no appreciable effects of supplemental vitamin D3 and/or calcium on individual or aggregate biomarkers of gut permeability. At baseline, a combined permeability score (the summed concentrations of all four biomarkers) was 14% lower among women (P = 0.01) and 10% higher among those who consumed >1 serving per day of red or processed meats relative to those who consumed none (P trend = 0.03). The permeability score was estimated to be 49% higher among participants with a body mass index (BMI) > 35 kg/m2 relative to those with a BMI < 22.5 kg/m2 (P trend = 0.17). Our results suggest that daily supplemental vitamin D3 and/or calcium may not modify circulating concentrations of gut permeability biomarkers within 1 or 3-5 years, but support continued investigation of modifiable factors, such as diet and excess adiposity, that could affect gut permeability. PREVENTION RELEVANCE: Calcium and vitamin D may be involved in regulating and maintaining the integrity of the intestinal mucosal barrier, the dysfunction of which results in exposure of the host to luminal bacteria, endotoxins, and antigens leading to potentially cancer-promoting endotoxemia and chronic colon inflammation. While our results suggest that daily supplementation with these chemopreventive agents does not modify circulating concentrations of gut permeability biomarkers, they support continued investigation of other potential modifiable factors, such as diet and excess adiposity, that could alter gut barrier function, to inform the development of treatable biomarkers of risk for colorectal neoplasms and effective colon cancer preventive strategies.

Markers of Systemic Inflammation and Environmental Enteric Dysfunction Are Not Reduced by Zinc or Multivitamins in Tanzanian Infants: A Randomized, Placebo-Controlled Trial.

OBJECTIVE: To examine whether daily zinc and/or multivitamin supplementation reduce biomarkers of environmental enteric dysfunction (EED), systemic inflammation, or markers of growth in a sample of infants from Dar es Salaam, Tanzania. STUDY DESIGN: Subgroup analysis of infants participating in a randomized, double-blind, placebo-controlled trial received daily oral supplementation of zinc, multivitamins, zinc + multivitamins, or placebo for 18 months starting at 6 weeks of age. EED (anti-flagellin and anti-lipopolysaccharide immunoglobulins), systemic inflammation (C-reactive protein and alpha-1-acid glycoprotein), and growth biomarkers (insulin-like growth factor-1 and insulin-like growth factor binding protein-3) were measured via enzyme-linked immunosorbent assay in a subsample of 590 infants at 6 weeks and 6 months of age. EED biomarkers also were measured in 162 infants at 12 months of age. RESULTS: With the exception of anti-lipopolysaccharide IgG concentrations, which were significantly greater in infants who received multivitamins compared with those who did not (1.41 ± 0.61 vs 1.26 ± 0.65, P = .006), and insulin-like growth factor binding protein-3 concentrations, which were significantly lower in children who received zinc compared with those who did not (981.13 ± 297.59 vs 1019.10 ± 333.01, P = .03), at 6 months of age, we did not observe any significant treatment effects of zinc or multivitamins on EED, systemic inflammation, or growth biomarkers. CONCLUSIONS: Neither zinc nor multivitamin supplementation ameliorated markers of EED or systemic inflammation during infancy. Other interventions should be prioritized for future trials. TRIAL REGISTRATION: Clinicaltrials.gov: NCT00421668.

Etiology of Diarrhea, Nutritional Outcomes, and Novel Intestinal Biomarkers in Tanzanian Infants.

OBJECTIVE: Diarrheal diseases are a leading cause of morbidity and mortality worldwide, but the etiology of diarrhea and its relation to nutritional outcomes in resource-limited settings is poorly defined. We sought to determine the etiology of community-acquired diarrhea in Tanzanian infants and to assess the association with anthropometrics and novel intestinal biomarkers. METHODS: A convenience sample of infants in a trial of zinc and/or multivitamin supplementation in Tanzania was selected. Subjects were enrolled at age 6 weeks and studied for 18 months. Stool samples were obtained from children with acute diarrhea. A novel, polymerase chain reaction-based TaqMan array was used to screen stool for 15 enteropathogens. A subset of subjects had serum gastrointestinal biomarkers measured. RESULTS: One hundred twenty-three subjects with diarrhea were enrolled. The mean ± SD age at stool sample collection was 12.4 ±â€Š3.9 months. Thirty-five enteropathogens were identified in 34 (27.6%) subjects: 11 rotavirus, 9 Cryptosporidium spp, 7 Shigella spp, 3 Campylobacter jejuni/coli, 3 heat stable-enterotoxigenic Escherichia coli, and 2 enteropathogenic E coli. Subjects with any identified enteropathogen had significantly lower weight-for-length z scores (-0.55 ±â€Š1.10 vs 0.03 ±â€Š1.30, P = 0.03) at the final clinic visit than those without an identified pathogen. Fifty of the 123 subjects (40.7%) had serum analyzed for antibodies to lipopolysaccharide (LPS) and flagellin. Subjects with any identified enteropathogen had lower immunoglobulin (IgA) antibodies to LPS (0.75 ±â€Š0.27 vs 1.13 ±â€Š0.77, P = 0.01) and flagellin (0.52 ±â€Š0.16 vs 0.73 ±â€Š0.47, P = 0.02) than those without an identified pathogen. CONCLUSIONS: This quantitative polymerase chain reaction method may allow identification of enteropathogens that place children at higher risk for suboptimal growth. IgA anti-LPS and flagellin antibodies hold promise as emerging intestinal biomarkers.