title: L-Arginine supplementation in mice enhances NO production in spleen cells and inhibits Plasmodium yoelii transmission in mosquitoes.
abstract: BACKGROUND
  The life cycle of Plasmodium is complex, requiring invasion of two different hosts, humans and mosquitoes. In humans, initiation of an effective Th1 response during early infection is critical for the control of parasite multiplication. In mosquitoes, inhibition of the development of sexual-stage parasites interrupts the parasite transmission. In this study, we aim to investigate whether dietary supplementation of L-arginine (L-Arg) in mice affects Plasmodium yoelii 17XL (Py17XL) transmission in mosquitoes.
  
  
  METHODS
  BALB/c mice were orally administered with 1.5 mg/g L-Arg daily for 7 days and infected with Py17XL. The mRNA levels of inducible nitric oxide synthase (iNOS) and arginase 1 in spleen cells were determined by real-time RT-PCR. The amount of nitric oxide (NO) released by spleen cells in vitro was determined by the Griess method. The effect of L-Arg supplementation on subsequent development of P. yoelii gametocytes was evaluated by an in vitro ookinete culture assay and mosquito feeding assay.
  
  
  RESULTS
  Pretreatment of mice with L-Arg significantly increased the transcript level of iNOS in spleen cells and the amount of NO synthesized. Dietary L-Arg supplementation also significantly reduced the number of zygotes and ookinetes formed during in vitro culture and the number of oocysts formed on mosquito midguts after blood feeding.
  
  
  CONCLUSIONS
  L-Arg enhances host immunity against blood-stage parasites as well as suppressing subsequent parasite development in mosquitoes. L-Arg as an inexpensive and safe supplement may be used as a novel adjunct treatment against malarial infection.
authors.affiliation: Department of Immunology, College of Basic Medical Sciences, China Medical University, No.77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning, 110122, P. R. China. zhengli@mail.cmu.edu.cn.
authors.forename: Li
authors.initials: L
authors.lastname: Zheng
authors.affiliation: Department of Immunology, College of Basic Medical Sciences, China Medical University, No.77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning, 110122, P. R. China. 66848464@qq.com.
authors.forename: Yanyan
authors.initials: Y
authors.lastname: Pan
authors.affiliation: Department of Immunology, College of Basic Medical Sciences, China Medical University, No.77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning, 110122, P. R. China. 156815643@qq.com.
authors.forename: Yonghui
authors.initials: Y
authors.lastname: Feng
authors.affiliation: Department of Immunology, College of Basic Medical Sciences, China Medical University, No.77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning, 110122, P. R. China. luc2@psu.edu.|Department of Entomology, Pennsylvania State University, University Park, PA, USA. luc2@psu.edu.
authors.forename: Liwang
authors.initials: L
authors.lastname: Cui
authors.affiliation: Department of Immunology, College of Basic Medical Sciences, China Medical University, No.77 Puhe Road, Shenyang North New Area, Shenyang, Liaoning, 110122, P. R. China. ymcao@mail.cmu.edu.cn.
authors.forename: Yaming
authors.initials: Y
authors.lastname: Cao
mesh_terms: D000818:Animals; D000852:Anopheles / Q000469:parasitology / Q000502:physiology*; D001120:Arginine / Q000378:metabolism*; D005260:Female; D006801:Humans; D007303:Insect Vectors / Q000469:parasitology / Q000502:physiology*; D008288:Malaria / Q000378:metabolism* / Q000469:parasitology / Q000635:transmission; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D009569:Nitric Oxide / Q000378:metabolism*; D010967:Plasmodium yoelii / Q000254:growth & development / Q000502:physiology*; D013154:Spleen / Q000378:metabolism*
chemical_list: D009569:Nitric Oxide; D001120:Arginine