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Amyloidosis comprises a group of chronic disease characterized by the deposition in different organs of an insoluble and fibrilar protein known as amyloid. AA-amyloidosis is commonly found in mammalian, including mice, and has been associated with inflammatory chronic diseases, such as leprosy, tuberculosis and rheumatoid arthritis, due to persistent high plasma concentration of SAA, a conserved protein. Leishmanasis are chronic diseases; however, the amyloidosis associated to them is rarely reported in the human being. Nevertheless, the association of leishmaniasis and amyloidosis has been described in the animal model during the course of infection. Mice experimentally infected by Leishmania amanozensis may present, after six months of infection, amyloid deposition in the liver, the spleen and less frequently in the ovaries. Macroscopically, these organs presented a whitish yellow-coloration diffusely distributed in the organ parenchyma. Histologicaly, the amyloid deposition is observed mainly among hepatocytes, in marginal zone of the spleen or in the renal glomerular tufts. Proteins are found in all cells and carry out a variety of important cellular functions. Folding and unfolding are crucial ways of regulating biological activity and targeting proteins to different cellular locations. Failure to fold correctly, or to remain correctly folded, will therefore give rise to the malfunctioning of living systems and hence to disease (Dobson, 2003). The largest group of misfolding diseases, which include numerous neurodegenerative disorders and the amyloidosis, originates from the conversion of specific proteins from their soluble functional states into stable, highly ordered, filamentous protein aggregates, known as amyloid fibrils (Uversky, 2003) In accordance to Xue et al. (2010), the time course of amyloidogenesis and the cellular responses to the presence of amyloid fibrils depends on the extent of fibril fragmentation and that length, width and surface area of amyloid fibrils may play important roles in the mechanism of amyloid deposition. The term amyloid was coined by the pathologist Virchow, in 1854, to describe an extracellular material found in the liver during the necroscopic exam. This term was used |
