Büyükgüzel, Ender | Büyükgüzel, Kemal | Erdem, Meltem | Adamski, Zbigniew | Adamski, Zbigniew | Marciniak, Pawel | Ziemnicki, Kazimierz

Article | 2013 | Archives of Insect Biochemistry and Physiology83 ( 1 ) , pp.15 - 24

Plant allelochemicals are nonnutritional chemicals that interfere with the biology of herbivores. We posed the hypothesis that ingestion of a glycoalkaloid allelochemical, ?-solanine, impairs biological parameters of greater wax moths Galleria mellonella. To test this idea, we reared wax moths on artificial diets with 0.015, 0.15, or 1.5 mg/100 g diet of ?-solanine. Addition of ?-solanine to the diet affected survival of seventh-instar larvae, pupae, and adults; and female fecundity and fertility. The diet containing the highest ?-solanine concentration led to decreased survivorship, fecundity, and fertility. The diets supplemented . . .with ?-solanine led to increased malondialdehyde and protein carbonyl contents in midgut and fat body and the effect was dose-dependent. Dietary ?-solanine led to increased midgut glutathione S-transferase activity and to decreased fat body glutathione S-transferase activitiy. We infer from these findings that ?-solanine influences life history parameters and antioxidative enzyme activities in the midgut and fat body of G. mellonella. © 2013 Wiley Periodicals, Inc Daha fazlası Daha az

Adamski, Zbigniew | Marciniak, Pawel | Ziemnicki, Kazimierz | Büyükgüzel, Ender | Erdem, Meltem | Büyükgüzel, Kemal | Ventrella, Emanuela

Article | 2014 | ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY87 ( 1 ) , pp.26 - 39

Plants synthesize a broad range of secondary metabolites that act as natural defenses against plant pathogens and herbivores. Among these, potato plants produce glycoalkaloids (GAs). In this study, we analyzed the effects of the dried extract of fresh potato leaves (EPL) on the biological parameters of the lepidopteran, Galleria mellonella (L.) and compared its activity to one of the main EPL components, the GA alpha-solanine. Wax moth larvae were reared from first instar on a diet supplemented with three concentrations of EPL or alpha-solanine. Both EPL and alpha-solanine affected survivorship, fecundity, and fertility of G. mellon . . .ella to approximately the same extent. We evaluated the effect of EPL and alpha-solanine on oxidative stress in midgut and fat body by measuring malondialdehyde (MDA) and protein carbonyl (PCO) contents, both biomarkers of oxidative damage. We evaluated glutathione S-transferase (GST) activity, a detoxifying enzyme acting in prevention of oxidative damage. EPL and alpha-solanine altered MDA and PCO concentrations and GST activity in fat body and midgut. We infer that the influence of EPL on G. mellonella is not enhanced by synergistic effects of the totality of potato leaf components compared to alpha-solanine alone. (C) 2014 Wiley Periodicals, Inc Daha fazlası Daha az

Büyükgüzel, Ender | Erdem, meltem | Tunaz, Hasan | Küçük, Ceyhun | Atılgan, Utku Can | Stanley, David | Büyükgüzel, Kemal

Article | 2017 | Comparative Biochemistry and Physiology -Part A : Molecular and Integrative Physiology204 , pp.121 - 128

We posed the hypothesis that inhibition of eicosanoid biosynthesis leads to increased lipid peroxidation in insects. Here we report that rearing the greater wax moth, Galleria mellonella, on media supplemented with selected inhibitors of eicosanoid biosynthesis throughout the larval, pupal and adult life led to major alterations in selected oxidative and antioxidative parameters of wax moth and its ectoparasitoid, Bracon hebetor. The highest dietary dexamethasone (Dex), esculetin (Esc) and phenidone (Phe) led to increased malondialdehyde (MDA) levels and to elevated catalase (CAT) and glutathione-S-transferase (GST) activities in al . . .l developmental stages of host larvae. Dietary Phe resulted in increased MDA levels, and CAT activity in G. mellonella adults by about 4-fold and about 2-fold, respectively. The Phe effect on GST activity in all stages of the wax moth was expressed in a dose-dependent manner, increased to 140 nmol/mg protein/min in larvae. MDA levels were increased by over 30-fold in adult wasps reared on Dex- and Esc-treated hosts. CAT and GST activities were increased in adult parasitoids reared on Esc-and Phe-treated hosts. GST activity of Dex-treated parasitoid larvae increased from about 4 to over 30 nmol/mg protein/min. Dietary Phe led to increased GST activity, by about 25-fold, in adult wasps. These data indicate that chronic inhibition of eicosanoid biosynthesis leads to increased oxidative stress, strongly supporting our hypothesis. The significance of this work lies in understanding the roles of eicosanoids in insect biology. Aside from other well-known eicosanoids actions, we propose that eicosanoids mediate reductions in oxidative stress. © 2016 Elsevier Inc Daha fazlası Daha az