title: Tumor necrosis factor alpha (TNF-alpha) levels in the brain and cerebrospinal fluid after meningitis induced by Streptococcus pneumoniae.
abstract: Bacterial meningitis due to Streptococcus pneumoniae is associated with a significant mortality rate and persisting neurologic sequelae including sensory-motor deficits, seizures, and impairments of learning and memory. The presence of proliferating bacteria within the subarachnoid and ventricular space compartments triggers an intense inflammatory host response at killing the invading microorganism. Proinflammatory mediators released in the process include tumor necrosis factor alpha (TNF-alpha), interleukin (IL)-1beta, IL-6. TNF-alpha have several effects, including cytotoxicity, antiviral activity, transcription factor activation, and immune response regulation. Thus, the aim of this study was to verify the levels of the TNF-alpha after pneumococcal meningitis in male Wistar rats. The animals underwent a magna cistern tap receiving either 10 microL sterile saline as a placebo or an equivalent volume of a S. pneumoniae suspension at the concentration 5 x 10(9)cfu/mL. The animals were killed at 0, 6, 12, 24, 48 and 96 h after induction. The brain was removed and hippocampus, cortex, prefrontal and cerebrospinal fluid (CSF) were isolated and used for the determination of TNF-alpha levels. We found an increase in TNF-alpha levels at 6h after induction of the meningitis in the hippocampus (p<0.01), frontal cortex (p<0.05), and cerebrospinal fluid (p<0.001).There was no alteration in the cortex. Our data suggest that TNF-alpha is involved in the pathophysiology of the pneumococcal meningitis and could be investigated as a putative biomarker for brain damage in the first hours.
authors.affiliation: Laboratório de Fisiopatologia Experimental and Instituto Nacional de Ciência e Tecnologia Translacional em Medicina, Programa de Pós-Graduação em Ciências da Saúde, Unidade Acadêmica de Ciências da Saúde, Universidade do Extremo Sul Catarinense, Criciúma, SC, Brazil. tba@unesc.net
authors.forename: Tatiana
authors.initials: T
authors.lastname: Barichello
authors.forename: Ivonete
authors.initials: I
authors.lastname: dos Santos
authors.forename: Geovana D
authors.initials: GD
authors.lastname: Savi
authors.forename: Anelise F
authors.initials: AF
authors.lastname: Florentino
authors.forename: Cintia
authors.initials: C
authors.lastname: Silvestre
authors.forename: Clarissa M
authors.initials: CM
authors.lastname: Comim
authors.forename: Gustavo
authors.initials: G
authors.lastname: Feier
authors.forename: Daniela
authors.initials: D
authors.lastname: Sachs
authors.forename: Mauro M
authors.initials: MM
authors.lastname: Teixeira
authors.forename: Antonio L
authors.initials: AL
authors.lastname: Teixeira
authors.forename: João
authors.initials: J
authors.lastname: Quevedo
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000032:analysis / Q000134:cerebrospinal fluid; D001921:Brain / Q000276:immunology* / Q000503:physiopathology; D002555:Cerebrospinal Fluid / Q000276:immunology / Q000378:metabolism / Q000382:microbiology; D003937:Diagnosis, Differential; D004195:Disease Models, Animal; D005625:Frontal Lobe / Q000276:immunology / Q000503:physiopathology; D006624:Hippocampus / Q000276:immunology / Q000503:physiopathology; D008297:Male; D008578:Meninges / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D008586:Meningitis, Pneumococcal / Q000134:cerebrospinal fluid* / Q000276:immunology* / Q000503:physiopathology; D011237:Predictive Value of Tests; D051381:Rats; D013290:Streptococcal Infections / Q000134:cerebrospinal fluid* / Q000276:immunology* / Q000503:physiopathology; D014409:Tumor Necrosis Factor-alpha / Q000032:analysis / Q000134:cerebrospinal fluid*; D015854:Up-Regulation / Q000276:immunology
chemical_list: D015415:Biomarkers; D014409:Tumor Necrosis Factor-alpha