Durmuş, Yonca | Büyükgüzel, Ender | Terzi, Burçin | Tunaz, Hasan | Stanley, David | Büyükgüzel, Kemal

Article | 2008 | Journal of Insect Physiology54 ( 1 ) , pp.17 - 24

Nodulation is the quantitatively predominant insect cellular immune function activated in response to bacterial, fungal and some viral infections. We posed the hypothesis that parasitoid insects express melanotic nodulation reactions to viral challenge and that eicosanoids mediate these reactions. Treating fifth-instar larvae of the ichneumonid endoparasitoid Pimpla turionellae with Bovine Herpes Simplex Virus-1 (BHSV-1) induced nodulation reactions in a challenge dose-dependent manner. Experimental larvae treated with the cyclooxygenase inhibitor, indomethacin, the lipoxygenase inhibitor, esculetin, and the phospholipase A2 inhibit . . .or, dexamethasone, resulted in severely impaired nodulation reactions to our standard BHSV-1 challenge dose. The immunoinhibitory influence of dexamethasone was reversed in larvae reared on culture medium amended with arachidonic acid, the fatty acid precursor of eicosanoid biosynthesis. Larvae that had been reared on media amended with indomethacin, esculetin, or dexamethasone were also compromised in their nodulation reactions to viral challenge. The influence of the orally administered pharmaceutical was expressed in a dose-dependent manner. Finally, wasp larvae reared in the presence of indomethacin and dexamethasone expressed significantly decreased levels of phenoloxidase activity in response to viral challenge. These findings draw attention to the idea that endoparasitoid insects express cellular immune reactions to viral challenge; they also support our hypothesis that eicosanoids mediate nodulation reactions to viral challenge in these highly specialized insects. © 2007 Elsevier Ltd. All rights reserved Daha fazlası Daha az

Durmuş, Yonca | Büyükgüzel, Kemal

Article | 2008 | Journal of Economic Entomology101 ( 3 ) , pp.777 - 783

Inorganic insecticides are commonly used in urban pest management because of their low mammalian toxicity. We tested the effects of sodium tetraborate (ST) on life parameters of greater wax moth, Galleria mellonella (L.) (Lepidoptera: Pyralidae), to determine its sublethal toxicity on the insect. Survival, development, adult longevity, and fecundity of the wax moth were investigated by rearing larvae on artificial diets containing ST at concentrations of 0.005,0.1,0.2, or 0.3%. Larvae reared on medium at the highest concentration of ST (0.3%) had significantly decreased survival to the seventh instar and prolonged time required to r . . .each the seventh instar. This concentration reduced pupa and adult yields to 12.5%, and it also prolonged development by 5 d. ST did not significantly influence adult longevity. Dietary ST led to significant decreases in fecundity and egg viability. Oviposition of survivors at the highest ST concentration (0.3%) was completely inhibited. Lysozyme content was decreased in larval hemolymph and fat body at high dietary ST concentrations. Fat body lysozyme content was significantly increased two-fold for larvae reared on diet at the lowest concentration of ST (0.005%). However, the highest concentration (0.3%) dramatically decreased fat body lysozyme content from 0.12 ± 0.013 to 0.006 ± 0.003 mg/ml in seventh instars. We infer that sublethal levels of dietary ST substantially influence life history parameters and immunocompetence in G. mellonella. © 2008 Entomological Society of America Daha fazlası Daha az

Hyršl, Pavel | Büyükgüzel, Ender | Büyükgüzel, Kemal

Article | 2008 | Acta Biologica Hungarica59 ( 3 ) , pp.281 - 288

The dietary effects of boric acid (BA) on the protein profiles of greater wax moth, Galleria mellonella (L.), were investigated in hemolymph and fat body of final instar (VIIth) and pupae. The insects were reared from first-instar larvae on an artificial diets containing 156, 620, 1250 or 2500 ppm of BA. We detected many undetermined protein fractions (6.5-260 kDa) in addition to well-defined protein fractions such as lipophorins and storage proteins in the tissues by using sodium dodecyl-sulphate polyacrylamide gradient gel electrophoresis. A marked quantitative change in the 45 kDa protein fraction of the hemolymph was observed in . . . the VIIth instar larvae reared on 2500 ppm dietary BA. © 2008 Akadémiai Kiadó Daha fazlası Daha az