title: In vivo optical imaging of motor neuron autophagy in a mouse model of amyotrophic lateral sclerosis.
abstract: Autophagy is involved in the pathological process of motor neuron death in amyotrophic lateral sclerosis (ALS). We have generated a novel double transgenic (DTg) mouse line by mating a green fluorescent protein (GFP)-fused microtubule-associated protein 1 light chain 3 (LC3) transgenic (LC3-Tg) mouse and a G93A mutant human Cu/Zn superoxide dismutase (mSOD1) transgenic (mSOD1-Tg) mouse. In vivo imaging of autophagy with these novel DTg mice was conducted at 10 (presymptomatic), 17 (early symptomatic) and 19 (late symptomatic) weeks of age. Fluorescence imaging analysis revealed a strong fluorescent signal in vivo over the T₃-S₁ level at 17 and 19 weeks of age only in the DTg mice. Ex vivo autophagy imaging of spinal cord sections (20 μm) also showed a progressive increase of the fluorescence signal from 17 to 19 weeks in DTg mice in the anterior horn at the L₄-₅ level, and the fluorescence signals were clearly observed in the gray matter of the spinal cord with a progressive increase of the signal and decreases in large motor neurons. Protein gel blot analysis revealed maximum LC3-I and LC3-II expressions at 19 weeks, consistent with the results from the in vivo autophagy imaging experiment. This method could also be applied as a unique tool for clarifying the role of autophagy, and to monitor the pathologic processes involving autophagy not only in ALS, but also other neurological diseases.
authors.affiliation: Department of Neurology, Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama University, Okayama, Japan.
authors.forename: Fengfeng
authors.initials: F
authors.lastname: Tian
authors.forename: Nobutoshi
authors.initials: N
authors.lastname: Morimoto
authors.forename: WenTao
authors.initials: W
authors.lastname: Liu
authors.forename: Yasuyuki
authors.initials: Y
authors.lastname: Ohta
authors.forename: Kentaro
authors.initials: K
authors.lastname: Deguchi
authors.forename: Kazunori
authors.initials: K
authors.lastname: Miyazaki
authors.forename: Koji
authors.initials: K
authors.lastname: Abe
mesh_terms: D000690:Amyotrophic Lateral Sclerosis / Q000175:diagnosis* / Q000473:pathology*; D000818:Animals; D001253:Astrocytes / Q000378:metabolism / Q000473:pathology; D001343:Autophagy; D002452:Cell Count; D003952:Diagnostic Imaging / Q000379:methods*; D004195:Disease Models, Animal; D005455:Fluorescent Antibody Technique; D049452:Green Fluorescent Proteins / Q000378:metabolism; D006801:Humans; D051379:Mice; D008822:Mice, Transgenic; D008869:Microtubule-Associated Proteins / Q000378:metabolism; D009046:Motor Neurons / Q000473:pathology*; D055620:Optical Phenomena; D010588:Phagosomes / Q000378:metabolism; D011993:Recombinant Fusion Proteins / Q000378:metabolism
chemical_list: C480860:Map1lc3b protein, mouse; D008869:Microtubule-Associated Proteins; D011993:Recombinant Fusion Proteins; D049452:Green Fluorescent Proteins