Improvement in Human Immune Function with Changes in Intestinal Microbiota by Salacia reticulata Extract Ingestion: A Randomized Placebo-Controlled Trial

• Published in: PloS one Vol. 10; no. 12; p. e0142909
• Main Authors: Oda, Yuriko, Ueda, Fumitaka, Utsuyama, Masanori, Kamei, Asuka, Kakinuma, Chihaya, Abe, Keiko, Hirokawa, Katsuiku
• Format: Journal Article
• Language: English
• Published: United States Public Library of Science 02.12.2015; Public Library of Science (PLoS)
• Subjects: Age; Animals; Bacteria; Biomarkers - metabolism; Blood; Blood cells; Cell proliferation; Clinical trials; Dendritic cells; Double-Blind Method; Eating; Epithelial cells; Gastrointestinal Microbiome - drug effects; Gene expression; Gene Expression Profiling; Genes; High-Throughput Nucleotide Sequencing - methods; Humans; Immune response; Immune system; Immunology; Ingestion; Intestinal microflora; Intestinal Mucosa - drug effects; Intestinal Mucosa - immunology; Intestinal Mucosa - metabolism; Intestinal Mucosa - microbiology; Intestine; Laboratories; Life sciences; Lymphocytes T; Male; Medical research; Methods; Microbiota; Microbiota (Symbiotic organisms); Middle Aged; Older people; Pharmaceuticals; Plant Extracts - pharmacology; Polyphenols; Prebiotics; R&D; Rats; Research & development; Rodents; Salacia; Salacia - chemistry; Sugar; Japan; California
• ISSN: 1932-6203; 1932-6203
• DOI: 10.1371/journal.pone.0142909

Plants belonging to the genus Salacia in the Hippocrateaceae family are known to inhibit sugar absorption. In a previous study, administration of Salacia reticulata extract in rats altered the intestinal microbiota and increased expression of immune-relevant genes in small intestinal epithelial cells. This study aimed to investigate the effect of S. reticulata extract in human subjects by examining the gene expression profiles of blood cells, immunological indices, and intestinal microbiota. The results revealed an improvement in T-cell proliferation activity and some other immunological indices. In addition, the intestinal microbiota changed, with an increase in Bifidobacterium and a decrease in Clostridium bacteria. The expression levels of many immune-relevant genes were altered in blood cells. We concluded that S. reticulata extract ingestion in humans improved immune functions and changed the intestinal microbiota. UMIN Clinical Trials Registry UMIN000011732.