Effects of oxidative stress on the virulence profile of Prevotella intermedia during experimental infection in gnotobiotic mice.
Prevotella intermedia is a component of the indigenous microbiota but is also responsible for anaerobic infections of the gastrointestinal tract and oral cavity. The aim of the present study was to investigate the influence of oxidative stress on the in vivo pathogenicity of P. intermedia. Germ-free mice were challenged intraperitoneally with parental (wt) or oxidative stress adapted (aero) strains. Bacterial virulence was evaluated by histopathology, hyperaemia and blood analysis [C-reactive protein (CRP), serum albumin and white blood cells (WBCs)], 3 and 10 days after challenge. CRP levels and WBC count were higher in animals challenged with the aero strain, and the albumin level was lower in this group, only 10 days after infection (P<0.05). Body weight gain was significantly reduced whereas hyperaemia and ratios of spleen/organ weight were increased in animals challenged with the aero strain (P<0.05). The liver of animals challenged with the aero strain showed hyperaemia, vasodilatation as well as an increase in the number of inflammatory cells and liver/organ weight ratio (P<0.05). Similar, but more discrete, alterations were observed in the small intestine of animals challenged with the aero strain. Studies on stress responses of this putative pathogen may help to better understand the aggressive potential and virulence markers of anaerobic bacteria.
Santos
Simone G
SG
Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
Diniz
Claúdio G
CG
Departamento de Parasitologia, Microbiologia e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil.
Silva
Vânia L
VL
Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
Martins
Wanderlany A
WA
Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
Cara
Denise C
DC
Departamento de Patologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
Souza
Natalia C
NC
Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
Serufo
José C
JC
Laboratório Micra Biotecnologia, Belo Horizonte, Minas Gerais, Brazil.
Nicoli
Jacques R
JR
Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
Carvalho
Maria Auxiliadora R
MAR
Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
Farias
Luiz M
LM
Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil.
D000818:Animals; D016866:Bacteroidaceae Infections / Q000382:microbiology* / Q000473:pathology; D001774:Blood Chemical Analysis; D001835:Body Weight; D015169:Colony Count, Microbial; D004195:Disease Models, Animal; D005856:Germ-Free Life; D006651:Histocytochemistry; D006940:Hyperemia; D007421:Intestine, Small / Q000473:pathology; D007958:Leukocyte Count; D008099:Liver / Q000473:pathology; D051379:Mice; D018384:Oxidative Stress; D018713:Prevotella intermedia / Q000276:immunology / Q000378:metabolism / Q000472:pathogenicity*; D013154:Spleen / Q000473:pathology; D014774:Virulence