Kinectics of the pulmonary phase of Schistosoma mansoni in mice treated with dexamethasone

Hermeto, Marco Victor; Bicalho, Rosilene Siray; Melo, Alan Lane de; Pereira, Leógenes Horácio

doi:10.1590/S0036-46651990000300004

Abstracts

In the experimental schistosomiasis mansoni glucocorticoids cause a reduction in the worm burden when administered in the week of infection or, the longest, at the next week. In order to determinate the probable(s) site(s) of reduction of the worm burden, mice were infected with cercariae of LE strain of S. mansoni and dexamethasone was administered daily (50 mg/kg, subcutaneously) starting 1 hour before infection until the eighth day. Mice were sacrificed daily starting on the third day after infection until the ninth day, and schistosomula from lungs were collected. Six weeks after infection, the remaining mice were sacrificed and perfused for adult worm recovery. Analysis of the results showed that the non-treated mice presented larger numbers of lung larvae than the treated ones, and this difference was also found later in the worm burden in the portal system. This difference may reflect the early death of larvae in treated animals, before or after reaching the lungs.

Schistosoma mansoni; Schistosomiasis; Dexamethasone; Glucocorticoids

Na esquistossomose mansoni experimental, os glicocorticóides causam uma redução na carga de vermes quando administrados na semana da infecção, ou, no mais tardar, na semana seguinte. A fim de determinar o(s) provável(is) sí-tio(s) de redução da carga de vermes, camundongos foram infectados com cercárias da cepa LE de S. mansoni e dexametasona foi administrada diariamente (50 mg/kg, subcutaneamente), iniciando 1 hora antes da infecção e prosseguindo até o 8º dia. Os camundongos foram sacrificados diariamente, do 3º ao 9º dia pós-infecção, e os esquistossômulos foram coletados. Os camundongos remanescentes foram sacrificados seis semanas após a infecção e perfundidos para recuperação dos vermes adultos. A análise dos resultados mostrou que os camundongos não tratados apresentavam números maiores de larvas pulmonares que os tratados, sendo que esta diferença foi também encontrada mais tarde na carga de vermes do sistema porta. Esta diferença pode representar a morte precoce das larvas nos animais tratados, no período pele-pulmão de seu desenvolvimento.

ORIGINAL ARTICLES

Kinectics of the pulmonary phase of Schistosoma mansoni in mice treated with dexamethasone

Cinética da fase pulmonar do Schistosoma mansoni em camundongos tratados com dexametasona

Marco Victor Hermeto; Rosilene Siray Bicalho; Alan Lane de Melo; Leógenes Horácio Pereira

Grupo Interdepartamental de Estudos Sobre Esquistossomose (GIDE), Universidade Federal de Minas Gerais, Caixa Postal 2486, CEP 30161 Belo Horizonte, MG, Brasil

SUMMARY

In the experimental schistosomiasis mansoni glucocorticoids cause a reduction in the worm burden when administered in the week of infection or, the longest, at the next week. In order to determinate the probable(s) site(s) of reduction of the worm burden, mice were infected with cercariae of LE strain of S. mansoni and dexamethasone was administered daily (50 mg/kg, subcutaneously) starting 1 hour before infection until the eighth day. Mice were sacrificed daily starting on the third day after infection until the ninth day, and schistosomula from lungs were collected. Six weeks after infection, the remaining mice were sacrificed and perfused for adult worm recovery. Analysis of the results showed that the non-treated mice presented larger numbers of lung larvae than the treated ones, and this difference was also found later in the worm burden in the portal system. This difference may reflect the early death of larvae in treated animals, before or after reaching the lungs.

Key words: Schistosoma mansoni; Schistosomiasis; Dexamethasone; Glucocorticoids.

RESUMO

Na esquistossomose mansoni experimental, os glicocorticóides causam uma redução na carga de vermes quando administrados na semana da infecção, ou, no mais tardar, na semana seguinte. A fim de determinar o(s) provável(is) sí-tio(s) de redução da carga de vermes, camundongos foram infectados com cercárias da cepa LE de S. mansoni e dexametasona foi administrada diariamente (50 mg/kg, subcutaneamente), iniciando 1 hora antes da infecção e prosseguindo até o 8º dia. Os camundongos foram sacrificados diariamente, do 3º ao 9º dia pós-infecção, e os esquistossômulos foram coletados. Os camundongos remanescentes foram sacrificados seis semanas após a infecção e perfundidos para recuperação dos vermes adultos. A análise dos resultados mostrou que os camundongos não tratados apresentavam números maiores de larvas pulmonares que os tratados, sendo que esta diferença foi também encontrada mais tarde na carga de vermes do sistema porta. Esta diferença pode representar a morte precoce das larvas nos animais tratados, no período pele-pulmão de seu desenvolvimento.

Full text available only in PDF format.

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Recebido para publicação em 18/09/1989.

This work was supported, in part, by CNPq, FINEP, CPq/UFMG (Brazil) and Parasitic Diseases Programme W.H.O. (Switzerland).

1. BARBOSA, M.A.; PELLEGRINO, J.; COELHO, P.M.Z. & SAMPAIO, I.B.M. Quantitative aspects of the migration and evolutive asynchronism of Schistosoma mansoni in mice. Rev. Inst. Med. trop. S. Paulo, 20: 121-132, 1978.
2. COKER, C.M. Effects of cortisone on immunity to Schistosoma mansoni in mice. Proc. Soc. exp. Biol. (N. Y.), 96: 1-3, 1957.
3. DOENHOFF, M.J. & LONG, E. Factors affecting the acquisition of resistance against Schistosoma mansoni in the mouse. IV. The inhability of T-cell deprived mice to reinfection, and other in vivo studies on the mechanisms of resistance. Parasitology, 78: 171-183, 1978.
4. HARRISON, R.A. & DOENHOFF, M.J. Retarded development of Schistosoma mansoni in immunosuppressed mice. Parasitology, 86: 429-438, 1983.
5. HERMETO, M.V.; BICALHO, R.S.; MELO, A.L. & PEREIRA, L.H. Schistosoma mansoni: transformaçăo da cercária em esquistossômulo sob imunossupressăo do hospedeiro. In: CONGRESSO DA SOCIEDADE BRASILEIRA DE MEDICINA TROPICAL, 25, Florianópolis, 1989. Anais. Florianópolis, 1989. p. 175.
6. KASS, E.H. & FINLAND, M. Adrenocortical hormones in infection and immunity. Ann. Rev. Microbiol., 7: 361-388, 1953.
7. LEWERT, R.M. & LEE, L. Studies on the passage of helminth larvae through host tissues. I. Histochemical studies of extracelular changes caused by penetrating larvae. II. Enzymatic activity of larvae in vitro and in vivo. J. infect. Dis., 95: 13-51, 1954.
8. LEWERT, R.M. & MANDLOWITZ, S. Innate immunity to Schistosoma mansoni relative to state of connective tissue. Ann. N. Y. Acad. Sci., 113: 54-62, 1963.
9. PELLEGRINO, J. & SIQUEIRA, A.F. Técnica de perfusăo para colheita de Schistosoma mansoni em cobaias experimentalmente infestadas. Rev. bras. Malar., 8: 589-597, 1956.
10. TORPIER, G.; HIM, M.; NIRDE, P.; de REGGI, M. & CAPRON, A. Detection of ecdysteroids in human trematode Schistosoma mansoni. Parasitology, 84: 123-130, 1982.
11. WEINMANN, C.J. & HUNTER, G.W. Studies on schistosomiasis. XIV. Effects of cortisone upon the Schistosoma mansoni burden in mice. J. Parasit., 45 (suppl.): 17, 1959.
12. WEINMANN, C.J. & HUNTER, G.W. Studies on schistosomiasis. XIV. Effects of cortisone upon the Schistosoma mansoni burden in mice. Exp. Parasit., 9: 239-242, 1960.

Publication Dates

Publication in this collection
13 Sept 2006
Date of issue
June 1990

History

Received
18 Sept 1989

This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.

[1] 1. BARBOSA, M.A.; PELLEGRINO, J.; COELHO, P.M.Z. & SAMPAIO, I.B.M. Quantitative aspects of the migration and evolutive asynchronism of Schistosoma mansoni in mice. Rev. Inst. Med. trop. S. Paulo, 20: 121-132, 1978.

[2] 2. COKER, C.M. Effects of cortisone on immunity to Schistosoma mansoni in mice. Proc. Soc. exp. Biol. (N. Y.), 96: 1-3, 1957.

[3] 3. DOENHOFF, M.J. & LONG, E. Factors affecting the acquisition of resistance against Schistosoma mansoni in the mouse. IV. The inhability of T-cell deprived mice to reinfection, and other in vivo studies on the mechanisms of resistance. Parasitology, 78: 171-183, 1978.

[4] 4. HARRISON, R.A. & DOENHOFF, M.J. Retarded development of Schistosoma mansoni in immunosuppressed mice. Parasitology, 86: 429-438, 1983.

[5] 5. HERMETO, M.V.; BICALHO, R.S.; MELO, A.L. & PEREIRA, L.H. Schistosoma mansoni: transformaçăo da cercária em esquistossômulo sob imunossupressăo do hospedeiro. In: CONGRESSO DA SOCIEDADE BRASILEIRA DE MEDICINA TROPICAL, 25, Florianópolis, 1989. Anais. Florianópolis, 1989. p. 175.

[6] 6. KASS, E.H. & FINLAND, M. Adrenocortical hormones in infection and immunity. Ann. Rev. Microbiol., 7: 361-388, 1953.

[7] 7. LEWERT, R.M. & LEE, L. Studies on the passage of helminth larvae through host tissues. I. Histochemical studies of extracelular changes caused by penetrating larvae. II. Enzymatic activity of larvae in vitro and in vivo. J. infect. Dis., 95: 13-51, 1954.

[8] 8. LEWERT, R.M. & MANDLOWITZ, S. Innate immunity to Schistosoma mansoni relative to state of connective tissue. Ann. N. Y. Acad. Sci., 113: 54-62, 1963.

[9] 9. PELLEGRINO, J. & SIQUEIRA, A.F. Técnica de perfusăo para colheita de Schistosoma mansoni em cobaias experimentalmente infestadas. Rev. bras. Malar., 8: 589-597, 1956.

[10] 10. TORPIER, G.; HIM, M.; NIRDE, P.; de REGGI, M. & CAPRON, A. Detection of ecdysteroids in human trematode Schistosoma mansoni. Parasitology, 84: 123-130, 1982.

[11] 11. WEINMANN, C.J. & HUNTER, G.W. Studies on schistosomiasis. XIV. Effects of cortisone upon the Schistosoma mansoni burden in mice. J. Parasit., 45 (suppl.): 17, 1959.

[12] 12. WEINMANN, C.J. & HUNTER, G.W. Studies on schistosomiasis. XIV. Effects of cortisone upon the Schistosoma mansoni burden in mice. Exp. Parasit., 9: 239-242, 1960.

Brasil

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Kinectics of the pulmonary phase of Schistosoma mansoni in mice treated with dexamethasone

Cinética da fase pulmonar do Schistosoma mansoni em camundongos tratados com dexametasona

Abstracts

Publication Dates

History