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From the cell biology to the development of new chemotherapeutic approaches against trypanosomatids: dreams and reality.

De Souza W - Kinetoplastid Biol Dis (2002)

Bottom Line: These organisms are also of biological interest since they are able to change the morphology according to the environment where they live, through a process of reversible cell transformation, and possess structures and organelles that are not found in mammalian cells.In addition, the present knowledge of structures and organelles such as the nucleus, the plasma membrane, the sub-pellicular microtubules, the flagellum, the kinetoplast-mitochondrion complex, the peroxisome (glycosome), the acidocalcisome and the structures and organelles involved in the endocytic pathway, is reviewed from a cell biology perspective.The possible use of available data for the development of new anti parasite drugs is also discussed.

View Article: PubMed Central - HTML - PubMed

Affiliation: Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofisica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, CCSBloco G, 21941900, Rio de JaneiroRJ, Brasil. wsouza@biof.ufrj.br

ABSTRACT
Members of the Trypanosomatidae family comprise a large number of species that are causative agents of important diseases such as sleeping sickness, Chagas' disease and Leishmaniasis. These organisms are also of biological interest since they are able to change the morphology according to the environment where they live, through a process of reversible cell transformation, and possess structures and organelles that are not found in mammalian cells. This review analyses the process of transformation, which takes place during the life cycle of Trypanosoma cruzi in the vertebrate and invertebrate hosts. Special attention is given to the interaction of the parasite with vertebrate cells. In addition, the present knowledge of structures and organelles such as the nucleus, the plasma membrane, the sub-pellicular microtubules, the flagellum, the kinetoplast-mitochondrion complex, the peroxisome (glycosome), the acidocalcisome and the structures and organelles involved in the endocytic pathway, is reviewed from a cell biology perspective. The possible use of available data for the development of new anti parasite drugs is also discussed.

No MeSH data available.


Related in: MedlinePlus

a: View of a triatomine after blood meal (courtesy of P Azambuja and E Garcia). b: Schematic view of the development of Trypanosma cruzi within the invertebrate host.
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Figure 3: a: View of a triatomine after blood meal (courtesy of P Azambuja and E Garcia). b: Schematic view of the development of Trypanosma cruzi within the invertebrate host.

Mentions: The biological cycle of T. cruzi starts when the invertebrate host feeds on the vertebrate host by sucking blood (Fig. 3). The invertebrate hosts are Hemiptera and Reduvidae such as Rhodinus prolixus, Triatoma infestans, and Panstrongylus megistus. During feeding, the trypomastigote forms in the blood of the infected vertebrate host are ingested by the insect. It has been assumed that in the stomach of the insect most of the bloodstream trypomastigotes transform into epimastigotes and some rounded forms. In the intestine the epimastigotes divide repeatedly by a process of binary fission and can attach to the intestinal cells by hemidesmosomes [7]. In the rectum a certain proportion of the epimastigotes transform into metacyclic trypomastigotes which are eliminated with the feces and are able to infect the vertebrate host [7-9]. It has been shown that the trypomastigote form can transform into a rounded form possessing a free flagellum. This form, which appears in the stomach, is able to transform into either short epimastigotes, which start a process of multiplication in the intestine, or into long epimastigotes that move to the more posterior region of the digestive tract of the bug. Apparently these long epimastigotes are unable to divide. Some days after the ingestion of infected blood, spheromastigotes, which are able to transform into trypomastigotes, are found in the rectum. Relying on the information available up to the present moment it seems that both, epimastigotes and the spheromastigotes, are able to transform into trypomastigotes. Based on these observations it is possible to develop alternatives for the control of T. cruzi transmission by inhibiting either the adhesion of the parasites to the intestinal cells, or the transformation of noninfective epimastigote into infective trypomastigote forms.


From the cell biology to the development of new chemotherapeutic approaches against trypanosomatids: dreams and reality.

De Souza W - Kinetoplastid Biol Dis (2002)

a: View of a triatomine after blood meal (courtesy of P Azambuja and E Garcia). b: Schematic view of the development of Trypanosma cruzi within the invertebrate host.
© Copyright Policy
Related In: Results  -  Collection

Show All Figures
getmorefigures.php?uid=PMC119324&req=5

Figure 3: a: View of a triatomine after blood meal (courtesy of P Azambuja and E Garcia). b: Schematic view of the development of Trypanosma cruzi within the invertebrate host.
Mentions: The biological cycle of T. cruzi starts when the invertebrate host feeds on the vertebrate host by sucking blood (Fig. 3). The invertebrate hosts are Hemiptera and Reduvidae such as Rhodinus prolixus, Triatoma infestans, and Panstrongylus megistus. During feeding, the trypomastigote forms in the blood of the infected vertebrate host are ingested by the insect. It has been assumed that in the stomach of the insect most of the bloodstream trypomastigotes transform into epimastigotes and some rounded forms. In the intestine the epimastigotes divide repeatedly by a process of binary fission and can attach to the intestinal cells by hemidesmosomes [7]. In the rectum a certain proportion of the epimastigotes transform into metacyclic trypomastigotes which are eliminated with the feces and are able to infect the vertebrate host [7-9]. It has been shown that the trypomastigote form can transform into a rounded form possessing a free flagellum. This form, which appears in the stomach, is able to transform into either short epimastigotes, which start a process of multiplication in the intestine, or into long epimastigotes that move to the more posterior region of the digestive tract of the bug. Apparently these long epimastigotes are unable to divide. Some days after the ingestion of infected blood, spheromastigotes, which are able to transform into trypomastigotes, are found in the rectum. Relying on the information available up to the present moment it seems that both, epimastigotes and the spheromastigotes, are able to transform into trypomastigotes. Based on these observations it is possible to develop alternatives for the control of T. cruzi transmission by inhibiting either the adhesion of the parasites to the intestinal cells, or the transformation of noninfective epimastigote into infective trypomastigote forms.

Bottom Line: These organisms are also of biological interest since they are able to change the morphology according to the environment where they live, through a process of reversible cell transformation, and possess structures and organelles that are not found in mammalian cells.In addition, the present knowledge of structures and organelles such as the nucleus, the plasma membrane, the sub-pellicular microtubules, the flagellum, the kinetoplast-mitochondrion complex, the peroxisome (glycosome), the acidocalcisome and the structures and organelles involved in the endocytic pathway, is reviewed from a cell biology perspective.The possible use of available data for the development of new anti parasite drugs is also discussed.

View Article: PubMed Central - HTML - PubMed

Affiliation: Laboratório de Ultraestrutura Celular Hertha Meyer, Instituto de Biofisica Carlos Chagas Filho, Universidade Federal do Rio de Janeiro, CCSBloco G, 21941900, Rio de JaneiroRJ, Brasil. wsouza@biof.ufrj.br

ABSTRACT
Members of the Trypanosomatidae family comprise a large number of species that are causative agents of important diseases such as sleeping sickness, Chagas' disease and Leishmaniasis. These organisms are also of biological interest since they are able to change the morphology according to the environment where they live, through a process of reversible cell transformation, and possess structures and organelles that are not found in mammalian cells. This review analyses the process of transformation, which takes place during the life cycle of Trypanosoma cruzi in the vertebrate and invertebrate hosts. Special attention is given to the interaction of the parasite with vertebrate cells. In addition, the present knowledge of structures and organelles such as the nucleus, the plasma membrane, the sub-pellicular microtubules, the flagellum, the kinetoplast-mitochondrion complex, the peroxisome (glycosome), the acidocalcisome and the structures and organelles involved in the endocytic pathway, is reviewed from a cell biology perspective. The possible use of available data for the development of new anti parasite drugs is also discussed.

No MeSH data available.


Related in: MedlinePlus