title: The S100B protein in biological fluids: more than a lifelong biomarker of brain distress.
abstract: S100B is a calcium-binding protein concentrated in glial cells, although it has also been detected in definite extra-neural cell types. Its biological role is still debated. When secreted, S100B is believed to have paracrine/autocrine trophic effects at physiological concentrations, but toxic effects at higher concentrations. Elevated S100B levels in biological fluids (CSF, blood, urine, saliva, amniotic fluid) are thus regarded as a biomarker of pathological conditions, including perinatal brain distress, acute brain injury, brain tumors, neuroinflammatory/neurodegenerative disorders, psychiatric disorders. In the majority of these conditions, high S100B levels offer an indicator of cell damage when standard diagnostic procedures are still silent. The key question remains as to whether S100B is merely leaked from injured cells or is released in concomitance with both physiological and pathological conditions, participating at high concentrations in the events leading to cell injury. In this respect, S100B levels in biological fluids have been shown to increase in physiological conditions characterized by stressful physical and mental activity, suggesting that it may be physiologically regulated and raised during conditions of stress, with a putatively active role. This possibility makes this protein a candidate not only for a biomarker but also for a potential therapeutic target.
authors.affiliation: Institute of Anatomy and Cell Biology, Università Cattolica Sacro Cuore, Roma, Italy. fabrizio.michetti@rm.unicatt.it
authors.forename: Fabrizio
authors.initials: F
authors.lastname: Michetti
authors.forename: Valentina
authors.initials: V
authors.lastname: Corvino
authors.forename: Maria Concetta
authors.initials: MC
authors.lastname: Geloso
authors.forename: Wanda
authors.initials: W
authors.lastname: Lattanzi
authors.forename: Camilla
authors.initials: C
authors.lastname: Bernardini
authors.forename: Laura
authors.initials: L
authors.lastname: Serpero
authors.forename: Diego
authors.initials: D
authors.lastname: Gazzolo
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D001826:Body Fluids / Q000378:metabolism*; D001921:Brain / Q000378:metabolism*; D001927:Brain Diseases / Q000473:pathology*; D006801:Humans; D001523:Mental Disorders / Q000473:pathology*; D009414:Nerve Growth Factors / Q000378:metabolism*; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins / Q000378:metabolism*
chemical_list: D015415:Biomarkers; D009414:Nerve Growth Factors; D064568:S100 Calcium Binding Protein beta Subunit; D009418:S100 Proteins; C579160:S100B protein, human