title: Preparation of selenium-enriched Bifidobacterium longum and its effect on tumor growth and immune function of tumor-bearing mice.
abstract: In this study, we demonstrated selenium (Se) accumulation in Bifidobacterium longum strain (B. longum) and evaluated the effect of Se-enriched B. longum (Se-B. longum) on tumor growth and immune function in tumor-bearing mice. Analysis using high-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS) revealed that more than 99% of Se in Se-B. longum was organic, the main component of which was selenomethionine (SeMet). In the in vivo experiments, tumor-bearing mice (n=8) were orally administrated with different doses of Se-B. longum alone or combined with cyclophosphamide (CTX). The results showed that the middle and high dose of Se-B. longum significantly inhibited tumor growth. When Se-B. longum and CTX were combined, the antitumor effect was significantly enhanced and the survival time of tumor-bearing mice (n=12) was prolonged. Furthermore, compared with CTX alone, the combination of Se-B. longum and CTX stimulated the activity of natural killer (NK) cells and T lymphocytes, increasing the levels of interleukin-2 (IL-2) and tumor necrosis factor-α (TNF-α), and the leukocyte count of H22 tumor-bearing mice (n=12).
authors.affiliation: Department of Biological Science and Technology and State Key Laboratory of Pharmaceutical Biotechnology, School of Life Sciences, Nanjing University, Nanjing,China E-mail : genxingxu@ nju.edu.cn, jjwang@nju.edu.cn.
authors.forename: Yan
authors.initials: Y
authors.lastname: Yin
authors.forename: Rong-Rong
authors.initials: RR
authors.lastname: Wang
authors.forename: Yan
authors.initials: Y
authors.lastname: Wang
authors.forename: Jian-Jun
authors.initials: JJ
authors.lastname: Wang
authors.forename: Gen-Xing
authors.initials: GX
authors.lastname: Xu
mesh_terms: D000818:Animals; D018906:Antineoplastic Agents, Alkylating / Q000494:pharmacology*; D001644:Bifidobacterium / Q000276:immunology / Q000378:metabolism*; D049109:Cell Proliferation / Q000187:drug effects*; D002851:Chromatography, High Pressure Liquid; D003520:Cyclophosphamide / Q000494:pharmacology*; D007376:Interleukin-2 / Q000276:immunology; D007694:Killer Cells, Natural / Q000187:drug effects* / Q000276:immunology; D013058:Mass Spectrometry; D051379:Mice; D008819:Mice, Nude; D012643:Selenium / Q000378:metabolism / Q000494:pharmacology*; D012645:Selenomethionine / Q000378:metabolism / Q000494:pharmacology*; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D014409:Tumor Necrosis Factor-alpha / Q000187:drug effects / Q000276:immunology; D023041:Xenograft Model Antitumor Assays
chemical_list: D018906:Antineoplastic Agents, Alkylating; D007376:Interleukin-2; D014409:Tumor Necrosis Factor-alpha; D003520:Cyclophosphamide; D012645:Selenomethionine; D012643:Selenium