Springer Nature is making SARS-CoV-2 and COVID-19 research free. View research | View latest news | Sign up for updates

Metabolism of ecdysteroids in the female tickAmblyomma hebraeum (Ixodoidea, Ixodidae): accumulation of free ecdysone and 20-hydroxyecdysone in the eggs

  • 85 Accesses

  • 12 Citations

Summary

[3H]-20-hydroxyecdysone ([3H]-20E) injected intoAmblyomma hebraeum females 7 days before the beginning of oviposition,viz. at the beginning of vitellogenesis, was converted to 3 polar peaks of unknown nature called 1, 2 and 3, and to apolar conjugates AP1, AP2 and AP3. AP2 have the same retention times as the esters of 20E with long chain fatty acids described inOrnithodoros moubata (Diehl et al. 1985). However, principally unmetabolized 20E was incorporated into the ovaries, and 16% of the injected labelling was recovered in the eggs, 3/4 being free 20E. When 20E was injected during oviposition, it was not converted to the polar products but only to the apolar products. At this time, 76% of the total radiolabel injected accumulated in the egg-batch, principally in the form of free unmetabolized 20E.

After injection of [3H]-ecdysone (3H]-E), the three polar metabolites 1′, 2′ and 3′, probably 20-deoxy homologues of 1, 2 and 3 described above were always produced irrespective of the time of injection. In addition, E was metabolized to 20E and to the apolar conjugates AP1, AP2, and AP3. E, 20E and peak 2′ were incorporated into the ovary within the first day after injection. These 3 compounds were found in freshly laid eggs in variable proportions, the quantity of E decreasing with time while 20E and peak 2′ increased. At the end of oviposition, ca. 60% of the injected radiolabel had been incorporated into the eggs. Apolar products and polar metabolites accumulating in the body were apparently not used as a source of free hormone for the eggs.

Our results with tritiated ecdysteroids confirm our data concerning endogenous ecdysteroids of the eggs ofA. hebraeum (Connat et al. 1985). This species, in contrast to 2 other female ticks,Ornithodoros moubata andBoophilus microplus, incorporates free E and 20E instead of ecdysteroid conjugates into its eggs. The role of these free ecdysteroids remains to be elucidated.

This is a preview of subscription content, log in to check access.

Abbreviations

ES :

ecdysteroids

E :

ecdysone

20E :

20-hydroxyecdysone

HPLC :

high-performance liquid chromatography

RP-18 :

reyerse phase with C18 aliphatic chains grafted on the silica

RIA :

radio-immunoassay

References

  1. Bergamasco R, Horn DHS (1983) Distribution and role of insect hormones in plants. In: Downer GH, Laufer H (eds) Endocrinology of Insects (Invertebrate endocrinology, vol I,) Alan R. Liss, New York, pp 627–654

  2. Bouvier J, Diehl PA, Morici M (1982) Ecdysone metabolism in the tickOrnithodoros moubata (Argasidae, Ixodoidea). Revue Suisse Zool 89:967–976

  3. Bullière D, Bullière F, De Reggi M (1979) Ecdysteroid titers during ovarian and embryonic development inBlaberus craniifer. Wilhelm Roux's Arch 182:255–275

  4. Connat J-L, Diehl PA, Morici M (1984) Metabolism of ecdysteroids during vitellogenesis of the tickOrnithodoros moubata (Ixodoidea, Argasidae): Accumulation of apolar metabolites in the eggs. Gen Comp Endrocrinol 56:100–110

  5. Connat J-L, Diehl PA, Gfeller H, Morici M (1985) Ecdysteroids in females and eggs of the Ixodid tickAmblyomma hebraeum. Internat J Invert Reprod Devel 8:103–116

  6. Connat J-L, Diehl PA (1986) Probable occurrence of ecdysteroid fatty acid esters in different classes of arthropods. Insect Biochem 16:91–97

  7. Connat J-L, Diehl PA, Thompson MJ (1986a) Possible inactivation of ingested ecdysteroids by conjugation with long-chain fatty acids in the female tickOrnithodoros moubata (Acarina: Argasidae). Arch Insect Biochem Physiol 3:235–252

  8. Connat J-L, Lafont R, Diehl PA (1986b) Metabolism of [3H]-ecdysone by isolated tissues of the female ixodid tickAmblyomma hebraeum (Ixodoidea: Ixodidae). Mol Cell Endocrinol 47:257–267

  9. Crosby T, Evershed RP, Lewis D, Wigglesworth K, Rees HH (1986) Identification of ecdysone 22-long chain fatty acyl esters in newly laid eggs of the cattle tickBoophilus microplus. Biochem J 240:131–138

  10. Daig K, Spindler KD (1983a) Uptake and retention of moulting hormones by the integument of crayfishesin vitro: I. Influence of temperature, hormone concentyration and hormone structure. Mol Cell Endrocrinol 31:93–104

  11. Daig K, Spindler KD (1983b) Uptake and retention of moulting hormones by the integument of crayfishesin vitro: II. Influence of metabolic inhibitors and sulphydryl group inhibitors. Mol Cell Endocrinol 32:73–79

  12. Dees WH, Sonenshine DE, Breidling E (1984) Ecdysteroids in the American dog tickDermacentor variabilis (Acari: Ixodidae) during different periods of tick development. J Med Entomol 21:514–523

  13. Delbecque JP, Diehl PA, O'Connor JD (1978a) Presence of ecdysone and ecdysterone in the tickAmblyomma hebraeum Koch. Experientia 34:1379–1380

  14. Delbecque JP, Lanzrein B, Bordereau C, Imboden H, Hirn M, O'Connor JD, Noirot C, Lüscher M (1978b) Ecdysone and ecdysterone in physogastric termite queens and eggs ofMacrotermes bellicosus andMacrotermes subhyalinus. Gen Comp Endocrinol 36:40–47

  15. Diehl PA, Germond JE, Morici M (1982) Correlations between ecdysteroid titers and integument structure in nymphs of the tickAmblyomma hebraeum Koch (Acarine: Ixodidae). Revue Suisse Zool 89:859–868

  16. Diehl PA, Connat J-L, Girault JP, Lafont R (1985) A new class of apolar ecdysteroid conjugates: esters of 20-hydroxy-ecdysone with long-chain fatty acids in ticks. Int J Invert Reprod 8:1–13

  17. Downer GH, Laufer H (1983) Endocrinology of insects (Invertebrate endocrinology, vol I). Alan R. Liss, New York

  18. Hinton HE (1981) Biology of insect eggs, vol I. Pergamon Press, Oxford

  19. Hoffmann J, Lagueux M (1985) Endocrine aspects of embryonic development in insects. In: Kerkut GA, Gilbert LI (eds) Embryogenesis and reproduction (Comprehensive insect physiology, biochemistry and pharmacology, vol I) Pergamon Press, Oxford New York Toronto, pp 435–460

  20. Hoffmann J, Porchet M (1984) Biosynthesis, metabolism and mode of action of invertebrate hormones. Springer, Berlin Heidelberg New York

  21. Hoffmann KH, Bulenda D, Thiry E, Schmid E (1985) Apolar ecdysteroid esters in adult female cricketsGryllus bimaculatus. Life Sci 37:185–192

  22. Isaac RE, Rees HH, Goodwin TW (1981) Isolation of 2-deoxy-20-hydroxyecdysone and 3-epi-2-deoxyecdysone from eggs of the desert locust,Schistocerca gregaria, during embryogenesis. Chem Communic:418–420

  23. Kaplanis JN, Thompson MJ, Dutky SR, Robbins WE (1980) The ecdysteroids from young embryonated eggs of the tobacco hornworm. Steroids 36:321–336

  24. Kubo I, Komatsu S, Asaka Y, De Boer G (1987) Isolation and identification of apolar metabolites of ingested 20-hydroxyecdysone in frass ofHeliothis virescens larvae. J Chem Ecol 13:785–794

  25. Lagueux M, Harry P, Hoffmann JA (1981) Ecdysteroids are bound to vitellin in newly laid eggs ofLocusta. Mol Cell Endocrinol 24:325–338

  26. Lagueux M, Hoffmann JA, Goltzené F, Kappler C, Tsoupras G, Hetru C, Luu B (1984) Ecdysteroids in ovaries and embryos ofLocusta migratoria. In: Hoffmann JA, Porchet M (eds) Biosynthesis, metabolism and mode of action of invertebrate hormones. Springer, Berlin Heidelberg New York

  27. Ma Wei Chun (1972) Dynamics of feeding responses inPieris brassicae Linn as a function of chemosensory input: a behavioral, ultrastructural and electrophysiological study. Meded Landbonwhogesch Wageningen 72-11:1–162

  28. Natori S, Ohtaki F (1976) Uptake of α-ecdysone by the fat body and membrane vesicles of fat body cells ofSarcophaga peregrina larvae. J Insect Physiol 22:227–234

  29. Norval RAI (1977) Studies on the ecology of the tickAmblyomma hebraeum Koch in the Eastern Cape Province of South Africa. II. Survival and development. J Parasitol 63:740–747

  30. Ogiso M, Ohnishi E (1984) Uptake and metabolism of [3H]-ecdysone in cultured ovaries of the silkworm,Bombyx mori. Mol Cell Endocrinol 38:13–19

  31. Ohnishi E (1986) Ovarian ecdysteroids ofBombyx mori: Retrospect and prospect. Zool Sci 3:401–407

  32. Sall C, Tsoupras G, Kappler C, Lagueux M, Zachary D, Luu B, Hoffmann JA (1983) Fate of maternal conjugated ecdysteroids during embryonic development inLocusta migratoria. J Insect Physiol 29:491–507

  33. Schoonhoven LM, Derksen-Koppers I (1973) Effects of secondary plant substances on drinking behaviour in some Heteroptera. Ent Exp Appl 16:141–145

  34. Warren JT, Steiner B, Dorn A, Pak M, Gilbert LI (1986) Metabolism of ecdysteroids during the embryogenesis ofManduca sexta. J Liq Chromat 9:1759–1782

  35. Whitehead DL, Osir EW, Obenchain FD, Thomas LS (1986) Evidence for the presence of ecdysteroids and preliminary characterization of their carrier proteins in the eggs of the brown ear tickRhipicephalus appendiculatus (Neumann). Insect Biochem 16:121–133

  36. Wigglesworth KP, Lewis D, Rees HH (1985) Ecdysteroids titre and metabolism to novel apolar derivatives in adult femaleBoophilus microplus (Ixodidae). Arch Insect Biochem Physiol 2:39–54

  37. Zhu XX, Gfeller H, Lanzrein B (1983) Ecdysteroids during oögenesis in the ovoviviparous cockroachNauphoeta cinerea. J Insect Physiol 29:225–235

Download references

Author information

Additional information

Part of this work was realized for the PhD thesis of E.M. Dotson

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Connat, J.-., Dotson, E.M. & Diehl, P.A. Metabolism of ecdysteroids in the female tickAmblyomma hebraeum (Ixodoidea, Ixodidae): accumulation of free ecdysone and 20-hydroxyecdysone in the eggs. J Comp Physiol B 157, 689–699 (1987). https://doi.org/10.1007/BF00700990

Download citation

Keywords

  • Ester
  • Retention Time
  • Human Physiology
  • Chain Fatty Acid
  • Ecdysone