title: Cerebrospinal Fluid from Sporadic Amyotrophic Lateral Sclerosis Patients Induces Mitochondrial and Lysosomal Dysfunction.
abstract: In our laboratory, we have developed (1) an in vitro model of sporadic Amyotrophic Lateral Sclerosis (sALS) involving exposure of motor neurons to cerebrospinal fluid (CSF) from sALS patients and (2) an in vivo model involving intrathecal injection of sALS-CSF into rat pups. In the current study, we observed that spinal cord extract from the in vivo sALS model displayed elevated reactive oxygen species (ROS) and mitochondrial dysfunction. Quantitative proteomic analysis of sub-cellular fractions from spinal cord of the in vivo sALS model revealed down-regulation of 35 mitochondrial proteins and 4 lysosomal proteins. Many of the down-regulated mitochondrial proteins contribute to alterations in respiratory chain complexes and organellar morphology. Down-regulated lysosomal proteins Hexosaminidase, Sialidase and Aryl sulfatase also displayed lowered enzyme activity, thus validating the mass spectrometry data. Proteomic analysis and validation by western blot indicated that sALS-CSF induced the over-expression of the pro-apoptotic mitochondrial protein BNIP3L. In the in vitro model, sALS-CSF induced neurotoxicity and elevated ROS, while it lowered the mitochondrial membrane potential in rat spinal cord mitochondria in the in vivo model. Ultra structural alterations were evident in mitochondria of cultured motor neurons exposed to ALS-CSF. These observations indicate the first line evidence that sALS-CSF mediated mitochondrial and lysosomal defects collectively contribute to the pathogenesis underlying sALS.
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, India.
authors.forename: Aparna
authors.initials: A
authors.lastname: Sharma
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, India.
authors.forename: Anu Mary
authors.initials: AM
authors.lastname: Varghese
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, India.
authors.forename: Kalyan
authors.initials: K
authors.lastname: Vijaylakshmi
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, India.
authors.forename: Rajendrarao
authors.initials: R
authors.lastname: Sumitha
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, India.
authors.forename: V K
authors.initials: VK
authors.lastname: Prasanna
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, India.
authors.forename: S
authors.initials: S
authors.lastname: Shruthi
authors.affiliation: Department of Neuropathology, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, India.
authors.forename: B K
authors.initials: BK
authors.lastname: Chandrasekhar Sagar
authors.affiliation: Institute of Bioinformatics, Discoverer Building, International Tech Park, Whitefield, Bangalore, 560066, India.
authors.forename: Keshava K
authors.initials: KK
authors.lastname: Datta
authors.affiliation: Institute of Bioinformatics, Discoverer Building, International Tech Park, Whitefield, Bangalore, 560066, India.
authors.forename: Harsha
authors.initials: H
authors.lastname: Gowda
authors.affiliation: Department of Neurology, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, India.
authors.forename: Atchayaram
authors.initials: A
authors.lastname: Nalini
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, India.
authors.forename: Phalguni Anand
authors.initials: PA
authors.lastname: Alladi
authors.affiliation: Department of Neurochemistry, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, India.
authors.forename: Rita
authors.initials: R
authors.lastname: Christopher
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, India.
authors.forename: Talakad N
authors.initials: TN
authors.lastname: Sathyaprabha
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, India.
authors.forename: Trichur R
authors.initials: TR
authors.lastname: Raju
authors.affiliation: Department of Neurochemistry, National Institute of Mental Health and Neurosciences (NIMHANS), Hosur Road, Bangalore, 560029, India. bharath@nimhans.kar.nic.in.
authors.forename: M M
authors.initials: MM
authors.lastname: Srinivas Bharath
mesh_terms: D000328:Adult; D000690:Amyotrophic Lateral Sclerosis / Q000134:cerebrospinal fluid* / Q000378:metabolism; D000818:Animals; D002478:Cells, Cultured; D005260:Female; D006801:Humans; D007278:Injections, Spinal; D008247:Lysosomes / Q000378:metabolism*; D008297:Male; D053078:Membrane Potential, Mitochondrial; D008565:Membrane Proteins / Q000378:metabolism; D008875:Middle Aged; D008928:Mitochondria / Q000502:physiology*; D024101:Mitochondrial Proteins / Q000378:metabolism; D009046:Motor Neurons / Q000378:metabolism / Q000648:ultrastructure; D018384:Oxidative Stress; D020543:Proteome / Q000378:metabolism; D011518:Proto-Oncogene Proteins / Q000378:metabolism; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D014020:Tissue Extracts / Q000494:pharmacology*; D025521:Tumor Suppressor Proteins / Q000378:metabolism
chemical_list: C116838:BNIP3L protein, human; D008565:Membrane Proteins; D024101:Mitochondrial Proteins; D020543:Proteome; D011518:Proto-Oncogene Proteins; D017382:Reactive Oxygen Species; D014020:Tissue Extracts; D025521:Tumor Suppressor Proteins
keywords: Cerebrospinal fluid; Lysosome; Mitochondria; Motor neuron disease; Oxidative stress; Proteomics; Respiratory chain complexes