title: Diet and abdominal autofluorescence detected by in vivo fluorescence imaging of living mice.
abstract: We investigated the effect of diet on abdominal autofluorescence detected by in vivo fluorescence imaging (FLI) of living mice. Groups of mice were fed a regular, alfalfa-free, or purified diet, and whole-body FLI was performed without the administration of fluorescent probes. In addition, quantum dots were injected intravenously into mice fed one of the three diets, and FLI was performed 3 and 24 hours later. Intense autofluorescence originating from the animals' intestinal contents was observed in mice fed the regular diet. Intestinal autofluorescence decreased substantially after feeding with the alfalfa-free diet and further after feeding with the purified diet. The decline was rapid and took only 1 to 2 days; however, it may have been affected by an intake of feces. The reticuloendothelial system was clearly delineated using a low dose of quantum dots in mice fed the purified diet. On the other hand, intestinal autofluorescence was visible 24 hours postinjection in mice given the alfalfa-free diet and definitely impaired the image quality in mice fed the regular diet. The use of a low-fluorescence diet, especially a purified diet, rapidly reduces intestinal autofluorescence and is expected to enhance the potential of in vivo FLI.
authors.affiliation: Department of Radiology, Institute of Medical Science, University of Tokyo, Tokyo, Japan. inoueys-tky@umin.ac.jp
authors.forename: Yusuke
authors.initials: Y
authors.lastname: Inoue
authors.forename: Kiyoko
authors.initials: K
authors.lastname: Izawa
authors.forename: Shigeru
authors.initials: S
authors.lastname: Kiryu
authors.forename: Arinobu
authors.initials: A
authors.lastname: Tojo
authors.forename: Kuni
authors.initials: K
authors.lastname: Ohtomo
mesh_terms: D000818:Animals; D004032:Diet; D005243:Feces; D005260:Female; D005453:Fluorescence; D007422:Intestines / Q000033:anatomy & histology*; D051379:Mice; D008807:Mice, Inbred BALB C; D012157:Mononuclear Phagocyte System; D045663:Quantum Dots; D013997:Time Factors; D051598:Whole Body Imaging