title: Chloroquine treatment increases detection of 5-fluorouracil-induced apoptosis index in vivo.
abstract: Although apoptosis can be readily assessed in vitro with a variety of techniques, the detection of apoptosis in the in vivo setting poses a much more difficult proposition. Apoptosis in an organism is followed almost inevitably by rapid clearance of dying cells via phagocytosis, thus limiting the ability to analyze apoptosis in vivo using classical techniques. To address this issue, we developed a method to enhance in vivo apoptosis detection using pretreatment with chloroquine, an inhibitor of macrophage activity, in Swiss albino mice. This technique resulted in a significant increase in the accumulation of apoptotic cells induced by 5-fluorouracil, as detected by propidium iodide staining in solid and ascitic forms of Ehrlich ascitic tumors and in bone marrow cells. We further validated our technique using DNA fragmentation and endonuclease assays. Our results demonstrated that chloroquine pretreatment can significantly enhance accumulation of apoptotic cells in organisms, and we envision combining this method with modern imaging techniques to optimize in vivo detection of apoptosis.
authors.affiliation: Department of Radiation Oncology, University of Michigan, Ann Arbor, MI 48109, USA. nyati@umich.edu
authors.forename: Mukesh K
authors.initials: MK
authors.lastname: Nyati
authors.forename: Felix Y
authors.initials: FY
authors.lastname: Feng
authors.forename: Vinayak D
authors.initials: VD
authors.lastname: Kanade
authors.forename: Rabindranath
authors.initials: R
authors.lastname: Nayak
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D001854:Bone Marrow Cells / Q000000981:diagnostic imaging / Q000187:drug effects; D002286:Carcinoma, Ehrlich Tumor / Q000000981:diagnostic imaging / Q000188:drug therapy; D002738:Chloroquine / Q000494:pharmacology* / Q000627:therapeutic use; D004357:Drug Synergism; D005472:Fluorouracil / Q000494:pharmacology*; D008297:Male; D051379:Mice; D008856:Microscopy, Fluorescence / Q000379:methods; D011859:Radiography
chemical_list: D002738:Chloroquine; D005472:Fluorouracil