title: Chitotriosidase - a putative biomarker for sporadic amyotrophic lateral sclerosis.
abstract: BACKGROUND
  Potential biomarkers to aid diagnosis and therapy need to be identified for Amyotrophic Lateral Sclerosis, a progressive motor neuronal degenerative disorder. The present study was designed to identify the factor(s) which are differentially expressed in the cerebrospinal fluid (CSF) of patients with sporadic amyotrophic lateral sclerosis (SALS; ALS-CSF), and could be associated with the pathogenesis of this disease.
  
  
  RESULTS
  Quantitative mass spectrometry of ALS-CSF and control-CSF (from orthopaedic surgical patients undergoing spinal anaesthesia) samples showed upregulation of 31 proteins in the ALS-CSF, amongst which a ten-fold increase in the levels of chitotriosidase-1 (CHIT-1) was seen compared to the controls. A seventeen-fold increase in the CHIT-1 levels was detected by ELISA, while a ten-fold elevated enzyme activity was also observed. Both these results confirmed the finding of LC-MS/MS. CHIT-1 was found to be expressed by the Iba-1 immunopositive microglia.
  
  
  CONCLUSIONS
  Elevated CHIT-1 levels in the ALS-CSF suggest a definitive role for the enzyme in the disease pathogenesis. Its synthesis and release from microglia into the CSF may be an aligned event of neurodegeneration. Thus, high levels of CHIT-1 signify enhanced microglial activity which may exacerbate the process of neurodegeneration. In view of the multifold increase observed in ALS-CSF, it can serve as a potential CSF biomarker for the diagnosis of SALS.
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Post Box no.: 2900, Bangalore 560 029, India.
authors.forename: Anu Mary
authors.initials: AM
authors.lastname: Varghese
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Post Box no.: 2900, Bangalore 560 029, India.
authors.forename: Aparna
authors.initials: A
authors.lastname: Sharma
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Post Box no.: 2900, Bangalore 560 029, India.
authors.forename: Poojashree
authors.initials: P
authors.lastname: Mishra
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Post Box no.: 2900, Bangalore 560 029, India.
authors.forename: Kalyan
authors.initials: K
authors.lastname: Vijayalakshmi
authors.affiliation: Institute of Bioinformatics, Discoverer Building, International Tech Park, Whitefield, Bangalore 560 066, India.
authors.forename: Hindalahalli Chandregowda
authors.initials: HC
authors.lastname: Harsha
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Post Box no.: 2900, Bangalore 560 029, India.
authors.forename: Talakad N
authors.initials: TN
authors.lastname: Sathyaprabha
authors.affiliation: Department of Neurochemistry, National Institute of Mental Health and Neuro Sciences, Hosur Road, Bangalore 560 029, India.
authors.forename: Srinivas Mm
authors.initials: SM
authors.lastname: Bharath
authors.affiliation: Department of Neurology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Bangalore 560 029, India.
authors.forename: Atchayaram
authors.initials: A
authors.lastname: Nalini
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Post Box no.: 2900, Bangalore 560 029, India.
authors.forename: Phalguni Anand
authors.initials: PA
authors.lastname: Alladi
authors.affiliation: Department of Neurophysiology, National Institute of Mental Health and Neuro Sciences, Hosur Road, Post Box no.: 2900, Bangalore 560 029, India.
authors.forename: Trichur R
authors.initials: TR
authors.lastname: Raju