title: Apoptosis as the adaptation mechanism in survival of Trichinella spiralis in the host.
abstract: The study evaluates the role of apoptosis-inducing factor (AIF) in the process of striated muscle cell transformation after occupation by Trichinella spiralis. Its relationship with other apoptosis-related factors [apoptotic protease-activating factor 1, Bcl-2 associated protein X (BAX), Bcl-2, caspase 3, survivin, poly (ADP-ribose) polymerase-1 (PARP-1), and endothelial and inducible (iNOS) nitric oxide synthase] was evaluated by immunohistochemistry. In the context of low BAX and caspase 3 expression and strong distribution of AIF in the sarcoplasm and nucleus at the very early stage of infection, we suppose that AIF-mediated signaling is involved in the apoptosis activation in the area of Trichinella occupation. In the time course of nurse cell formation, survivin and caspase 3 migrated into the enlarged nuclei with strong PARP-1 expression. In the end of encapsulation of Trichinella, expression of all proapoptotic factors ceased and only survivin in the nuclei and Bcl-2 positivity in the cytoplasm persisted in the formed nurse cell. The expression of sarcoplasmic iNOS was absent during the process of muscle cell de-differentiation and reappeared within the nurse cell. It seems that upregulation and downregulation of factors of apoptosis in the skeletal muscle cell represents an adaptive mechanism providing a comfortable niche for the parasite.
authors.affiliation: Department of Pathology, Faculty of Medicine, Comenius University in Bratislava, Bratislava, Slovakia. pavel.babal@fmed.uniba.sk
authors.forename: Pavel
authors.initials: P
authors.lastname: Babal
authors.forename: Rosica
authors.initials: R
authors.lastname: Milcheva
authors.forename: Svetlozara
authors.initials: S
authors.lastname: Petkova
authors.forename: Pavol
authors.initials: P
authors.lastname: Janega
authors.forename: Zuzana
authors.initials: Z
authors.lastname: Hurnikova
mesh_terms: D000222:Adaptation, Physiological; D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D051033:Apoptosis Inducing Factor / Q000235:genetics / Q000378:metabolism; D053477:Apoptotic Protease-Activating Factor 1 / Q000235:genetics / Q000378:metabolism; D053148:Caspase 3 / Q000235:genetics / Q000378:metabolism; D002467:Cell Nucleus / Q000378:metabolism / Q000469:parasitology / Q000648:ultrastructure; D004789:Enzyme Activation; D005786:Gene Expression Regulation; D006790:Host-Parasite Interactions; D007150:Immunohistochemistry; D007814:Larva / Q000502:physiology*; D051379:Mice; D008807:Mice, Inbred BALB C; D008928:Mitochondria / Q000201:enzymology* / Q000469:parasitology / Q000648:ultrastructure; D032342:Muscle Cells / Q000378:metabolism* / Q000469:parasitology / Q000648:ultrastructure; D052247:Nitric Oxide Synthase Type II / Q000235:genetics / Q000378:metabolism; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases / Q000235:genetics / Q000378:metabolism; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000235:genetics / Q000378:metabolism; D015398:Signal Transduction; D017160:Trichinella spiralis / Q000502:physiology*; D014235:Trichinellosis / Q000378:metabolism / Q000469:parasitology; D051028:bcl-2-Associated X Protein / Q000235:genetics / Q000378:metabolism
chemical_list: D051033:Apoptosis Inducing Factor; D053477:Apoptotic Protease-Activating Factor 1; D019253:Proto-Oncogene Proteins c-bcl-2; D051028:bcl-2-Associated X Protein; C496319:NOS2 protein, human; D052247:Nitric Oxide Synthase Type II; C499321:Parp1 protein, mouse; D000071137:Poly (ADP-Ribose) Polymerase-1; D011065:Poly(ADP-ribose) Polymerases; D053148:Caspase 3