title: Hematopoietic response of rats exposed to the impact of an acute psychophysiological stressor on responsiveness to an in vivo challenge with Listeria monocytogenes: modulation by Chlorella vulgaris prophylactic treatment.
abstract: In this study, we investigated the hematopoietic response of rats pretreated with CV and exposed to the impact of acute escapable, inescapable or psychogenical stress on responsiveness to an in vivo challenge with Listeria monocytogenes. No consistent changes were observed after exposure to escapable footshock. Conversely, the impact of uncontrollable stress (inescapable and psychogenical) was manifested by an early onset and increased severity and duration of myelossuppression produced by the infection. Small size CFU-GM colonies and increased numbers of clusters were observed, concurrently to a greater expansion in the more mature population of bone marrow granulocytes. No differences were observed between the responses of both uncontrollable stress regimens. CV prevented the myelossuppression caused by stress/infection due to increased numbers of CFU-GM in the bone marrow. Colonies of cells tightly packed, with a very condensed nucleus; in association with a greater expansion in the more immature population of bone marrow granulocytes were observed. Investigation of the production of colony-stimulating factors revealed increased colony-stimulating activity (CSA) in the serum of normal and infected/stressed rats treated with the algae. CV treatment restored/enhanced the changes produced by stress/infection in total and differential bone marrow and peripheral cells counts. Further studies demonstrated that INF-gamma is significantly reduced, whereas IL-10 is significantly increased after exposure to uncontrollable stress. Treatment with CV significantly increased INF-gamma levels and diminished the levels of IL-10. Uncontrollable stress reduced the protection afforded by CV to a lethal dose of L. monocytogenes, with survival rates being reduced from (50%) in infected rats to 20% in infected/stressed rats. All together, our results suggest Chlorella treatment as an effective tool for the prophylaxis of post-stress myelossupression, including the detrimental effect of stress on the course and outcome of infections.
authors.affiliation: Departamento de Farmacologia and Hemocentro, Faculdade de Ciências Médicas, Universidade Estadual de Campinas (UNICAMP), C.P. 6111, CEP 13083-970, Campinas, SP, Brazil; Laboratório de Farmacologia Aplicada e Toxicologia, Escola de Medicina Veterinária, Universidade de São Paulo (USP), São Paulo, SP, Brazil.
authors.forename: Julia
authors.initials: J
authors.lastname: Souza Queiroz
authors.affiliation: Departamento de Farmacologia and Hemocentro, Faculdade de Ciências Médicas, Universidade Estadual de Campinas (UNICAMP), C.P. 6111, CEP 13083-970, Campinas, SP, Brazil.
authors.forename: Cristiane Okuda
authors.initials: CO
authors.lastname: Torello
authors.affiliation: Laboratório de Farmacologia Aplicada e Toxicologia, Escola de Medicina Veterinária, Universidade de São Paulo (USP), São Paulo, SP, Brazil.
authors.forename: João
authors.initials: J
authors.lastname: Palermo-Neto
authors.affiliation: Laboratório de Farmacologia e Toxicologia Celular, Faculdade de Farmácia, Universidade Federal de Goiás (UFG), Goiânia, GO, Brazil.
authors.forename: Marize C
authors.initials: MC
authors.lastname: Valadares
authors.affiliation: Departamento de Farmacologia and Hemocentro, Faculdade de Ciências Médicas, Universidade Estadual de Campinas (UNICAMP), C.P. 6111, CEP 13083-970, Campinas, SP, Brazil. Electronic address: mlsq@fcm.unicamp.br.
authors.forename: Mary L S
authors.initials: MLS
authors.lastname: Queiroz
mesh_terms: D000208:Acute Disease; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D001854:Bone Marrow Cells / Q000166:cytology / Q000378:metabolism; D048408:Chlorella vulgaris / Q000276:immunology; D003115:Colony-Stimulating Factors / Q000097:blood / Q000378:metabolism; D004597:Electroshock / Q000009:adverse effects / Q000379:methods; D004924:Escape Reaction / Q000502:physiology; D006098:Granulocytes / Q000166:cytology / Q000378:metabolism; D006413:Hematopoietic System / Q000503:physiopathology*; D016753:Interleukin-10 / Q000097:blood / Q000378:metabolism; D007377:Interleukin-3 / Q000097:blood / Q000378:metabolism; D008089:Listeria monocytogenes / Q000254:growth & development / Q000276:immunology; D008088:Listeriosis / Q000382:microbiology / Q000503:physiopathology*; D008297:Male; D051381:Rats; D017208:Rats, Wistar; D013315:Stress, Psychological / Q000209:etiology / Q000503:physiopathology*; D016019:Survival Analysis; D013997:Time Factors
chemical_list: D003115:Colony-Stimulating Factors; D007377:Interleukin-3; D016753:Interleukin-10