Effects of oxidative stress on the virulence profile of Prevotella intermedia during experimental infection in gnotobiotic mice

• Published in: Journal of medical microbiology Vol. 56; no. 3; pp. 289 - 297
• Main Authors: Santos, Simone G, Diniz, Claudio G, Silva, Vania L, Martins, Wanderlany A, Cara, Denise C, Souza, Natalia C, Serufo, Jose C, Nicoli, Jacques R, Carvalho, Maria Auxiliadora R, Farias, Luiz M
• Format: Journal Article
• Language: English
• Published: Reading Soc General Microbiol 01.03.2007; Society for General Microbiology
• Subjects: Animals; Bacteroidaceae Infections - microbiology; Bacteroidaceae Infections - pathology; Biological and medical sciences; Blood Chemical Analysis; Body Weight; Colony Count, Microbial; Disease Models, Animal; Fundamental and applied biological sciences. Psychology; Germ-Free Life; Histocytochemistry; Hyperemia; Infectious diseases; Intestine, Small - pathology; Leukocyte Count; Liver - pathology; Medical sciences; Mice; Microbiology; Oxidative Stress; Prevotella intermedia; Prevotella intermedia - immunology; Prevotella intermedia - metabolism; Prevotella intermedia - pathogenicity; Spleen - pathology; Virulence; Oxidative stress; Vertebrata; Gnotobiotic animal; Mammalia; Microbiology; Prevotella intermedia; Mouse; Virulence; Rodentia; Bacteria; Bacteroidaceae
• ISSN: 0022-2615; 1473-5644
• DOI: 10.1099/jmm.0.46748-0

1 Departamento de Microbiologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil 2 Departamento de Parasitologia, Microbiologia e Imunologia, Instituto de Ciências Biológicas, Universidade Federal de Juiz de Fora, Juiz de Fora, Minas Gerais, Brazil 3 Departamento de Parasitologia, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil 4 Departamento de Patologia Geral, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Belo Horizonte, Minas Gerais, Brazil 5 Laboratório Micra Biotecnologia, Belo Horizonte, Minas Gerais, Brazil Correspondence Luiz M. Farias macedo{at}icb.ufmg.br Received 30 May 2006 Accepted 30 October 2006 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. Abbreviations: aero strain, oxidative stress adapted strain; CRP, C-reactive protein; RBC, red blood cell; WBC, white blood cell; wt strain, parental strain.