Ecotoxicological Effects of Titanium Aluminum Carbide Composites on Biochemical and Metabolic Parameters of Galleria mellonella.

Metal composites have been extensively used in various fields such as automotive industry, medicine and pharmacy. However, the high exposure of these chemicals may have an adverse effect on the living organisms. In this study, the effect of titanium aluminum carbide (Ti3AlC2) on the model organism Galleria mellonella was investigated. The change in the metabolic enzymes such as alanine transferase, aspartate transferase, gamma-glutamyl transferase, lactate dehydrogenase, amylase, creatine kinase, alkaline phosphatase in the hemolymph of G. mellonella which was exposed to Ti3AlC2 was determined. The contents of the bilirubin, albumin, uric acid and the total protein were also measured after the Ti3AlC2 exposure on the model organism. The results of our study clearly indicate that Ti3AlC2 has adverse effects on the model organism G. mellonella.

Effects of Copper Oxide Nanoparticles on Immune and Metabolic Parameters of Galleria mellonella L.

In this study, the effects of dietary CuO nanoparticles (NPs) on metabolic enzyme activity, biochemical parameters, and total (THC) and differential hemocyte counts (DHC) were determined in Galleria mellonella larvae. Using concentrations of 10, 100, 1000 mg/L and the LC10 and LC30 levels of CuO NPs, we determined that the NPs negatively impacted metabolic enzyme activity and biochemical parameters in larval hemolymph. Compared with the control, the greatest increase in THC was observed in larvae fed on diets with 100 mg L-1 of CuO NPs. Plasmatocytes and granulocytes were among the most numerous hemocytes in all treatments. These results suggest that dietary CuO NPs effects the metabolic metabolism and immune system of G. mellonella and provide indirect information regarding the toxic effects of CuO NPs in mammalian immune system given similarities between mammalian blood cells and insect hemocytes.

Inhibition of eicosanoid signaling leads to increased lipid peroxidation in a host/parasitoid system.

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 all 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 140nmol/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 30nmol/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.

Ingestion of the anti-bacterial agent, gemifloxacin mesylate, leads to increased gst activity and peroxidation products in hemolymph of Galleria mellonella l. (lepidoptera: pyralidae).

Gemifloxacin mesylate (GEM) is a synthetic, fourth-generation fluoroquinolone antibacterial antibiotic that has a broad spectrum of activity against bacteria. GEM inhibits DNA synthesis by inhibiting DNA gyrase and topoisomerase IV activities. Recent research into insect nutrition and mass-rearing programs, in which antibiotics are incorporated into the culture media to maintain diet quality, raised a question of whether clinical antibiotics influence the health or biological performance of the insects that ingest these compounds. Because some antibiotics are pro-oxidant compounds, we addressed the question with experiments designed to assess the effects of GEM (mesylate salt) on oxidative stress indicators, using Galleria mellonella larvae. The insects were reared from first-instar larvae to adulthood on artificial diets amended with GEM at 0.001, 0.01, 0.1, or 1.0%. Feeding on the 1% diets led to significantly increased hemolymph contents of the lipid peroxidation product, malondialdehyde and protein oxidation products, protein carbonyl. All GEM concentrations led to increased hemolymph glutathione S-transferase activity. We inferred that although it was not directly lethal to G. mellonella larvae, dietary exposure to GEM exerts measurable oxidative damage, possibly on insects generally. Long-term, multigenerational effects remain unknown.

Reduced Fitness in Adults From Larval, Galleria mellonella (Lepidoptera: Pyralidae) Reared on Media Amended With the Antihelmintic, Mebendazole.

Benzimidazole antihelmintics, including mebendazole, have a broad antiparasitic spectrum. These drugs play a major role in the treatments of parasites of intestines or other organs of vertebrates, humans, and other animals.The impact of mebendazole on the biology of the greater wax moth, Galleria mellonella (L.), was assessed by observation of several developmental parameters as follows: survivorship, developmental time, and adult longevity. Sublethal toxicity was measured through reproductive parameters such as fecundity and hatchability.The larvae were reared on artificial diet from first-instar larvae to the adult stage in the laboratory. The diets contained mebendazole at different concentrations of 0.005, 0.05, 0.5, or 1.0%. Control diet did not containme bendazole and produced seventh-instar larvae in 96.6±1.67% of cases, whereas the addition of mebendazole into diet at 1.0% significantly decreased survivorship of seventh-instar larvae to 79.9±4.08%. The diet with the highest concentration of mebendazole decreased survivorship in the adult stage from 79.9±2.35 to 56.6±4.73%, and shortened the developmental time for adult emergence from 36.7±0.48 to 34.1±0.63 d. All mebendazole concentrations shortened adult longevity and significantly decreased fecundity and hatch ability of G. mellonella. The highest dietary concentration of this antihelmintic significantly decreased the egg number to 28.6±2.89 and hatching rate to 51.7±1.85%. The present study demonstrates that mebendazole exhibits significant adverse effects on greater wax moth, leading to deteriorated life table parameters and decreased adult fitness.

THE EFFECTS OF XANTHOTOXIN ON THE BIOLOGY AND BIOCHEMISTRY OF Galleria mellonella L. (LEPIDOPTERA: PYRALIDAE).

The effects of a dietary plant allelochemical, xanthotoxin (XA), on survivorship, development, male and female adult longevity, fecundity, and hatchability of the greater wax moth Galleria mellonella L. were investigated. Oxidative stress indicators, the lipid peroxidation product, malondialdehyde (MDA), and protein oxidation products, protein carbonyl (PCO) contents, and activities of a detoxification enzyme glutathione S-transferase (GST) activity were determined in wax moth adults. The insect was reared from first-instar larvae on an artificial diets containing XA at 0.001, 0.005, or 0.1% to adult stage in laboratory conditions. Relative to the controls, the diets containing XA concentrations led to decreased survivorship in seventh instar, pupal, and adult stages. Compared to control diet (77.7%), the highest dietary XA concentration decreased survivorship to adulthood to 11.0%. The highest XA concentration (0.1%) reduced female longevity from 10.4 to 5.7 days and decreased egg numbers from 95.0 to 33.5 and hatchability from 82.7 to 35.6%. The lowest XA concentration (0.001%) led to about a sixfold increase in MDA content. XA at high concentrations (0.005 and 0.1%) increased MDA (by threefold) and protein carbonyl (by twofold) contents decreased GST activity. The highest dietary XA concentration decreased GST activity from 0.28 ± 0.025 to 0.16 ± 0.005 µmol/mg protein/min. We infer from these findings that XA-induced oxidative stress led to decreased biological fitness.

Potato leaf extract and its component, α-solanine, exert similar impacts on development and oxidative stress in Galleria mellonella L.

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 α-solanine. Wax moth larvae were reared from first instar on a diet supplemented with three concentrations of EPL or α-solanine. Both EPL and α-solanine affected survivorship, fecundity, and fertility of G. mellonella to approximately the same extent. We evaluated the effect of EPL and α-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 α-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 α-solanine alone.

Effect of boric acid on antioxidant enzyme activity, lipid peroxidation, and ultrastructure of midgut and fat body of Galleria mellonella.

Boric acid is widely used as an insecticide, acaricide, herbicide, and fungicide and also during various industrial processings. Hence, numerous populations are subjects to this toxic compound. Its action on animals is still not fully known and understood. We examined the effect of boric acid on larvae of greater wax moth (Galleria mellonella). The chemical appeared to be toxic for larvae, usually in a concentration-dependent manner. Exposed groups revealed increased lipid peroxidation and altered activity of catalase, superoxide dismutase, glutathione S-transferase, and glutathione peroxidase. We also observed changes of ultrastructure, which were in tune with biochemical assays. We suggest that boric acid has a broad mode of action, which may affect exposed larvae, and even if sublethal, they may lead to disturbances within exposed populations.

The influence of dietary α-solanine on the waxmoth Galleria mellonella L.

Plant allelochemicals are nonnutritional chemicals that interfere with the biology of herbivores. We posed the hypothesis that ingestion of a glycoalkaloid allelochemical, α-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 α-solanine. Addition of α-solanine to the diet affected survival of seventh-instar larvae, pupae, and adults; and female fecundity and fertility. The diet containing the highest α-solanine concentration led to decreased survivorship, fecundity, and fertility. The diets supplemented with α-solanine led to increased malondialdehyde and protein carbonyl contents in midgut and fat body and the effect was dose-dependent. Dietary α-solanine led to increased midgut glutathione S-transferase activity and to decreased fat body glutathione S-transferase activitiy. We infer from these findings that α-solanine influences life history parameters and antioxidative enzyme activities in the midgut and fat body of G. mellonella.

Oxidative and genotoxic effect of piperazine on Galleria mellonella (Lepidoptera: Pyralidae) hemolymph.

Recently, there are many studies suggesting antibacterial, antifungal, and anthelmintic agents as alternative chemicals to insecticides. In this study, the oxidative and genotoxic effect of Piperazine, a clinically important hexahydropyrazine anthelmintic, on Galleria mellonella L. hemolymph tissue by adding artificial diet were investigated. Galleria mellonella larvae were reared until 7th larval stage in artificial diet containing 0.001, 0.01, 0.1, and 1 g piperazine per 100 g of diet. Using hemolymph collected from 7th-instar larvae, the amount of lipid peroxidation final product malondialdehyde (MDA), protein oxidation product protein carbonyl (PCO), and detoxification enzymes glutathione S-transferase (GST) and cytochrome P450 monooxygenase (cyt P450) activity, comet assay were measured. According to the results obtained, when the piperazine high concentrations tested with the control group were compared, statistically significant differences were found in MDA, PCO content, cyt P450, GST activity, and comet assay in the hemolymph of the insect. While MDA content was 0.01 ± 0.0021 nmol/mg protein in the control group, this amount increased approximately 2-fold at the highest concentration (0.0231 ± 0.0050 nmol/mg protein). On the other hand, when the control group and the highest piperazine concentration were compared in the GST and cyt P450 activity, it was determined that there was a statistically significant increase. We obtained similar results in comet assay and micronucleus formation data. This study showed that the tested piperazine concentrations caused significant changes in the detoxification capacity, oxidative stress, and genotoxic markers in the insect's hemolymph tissue.

Eicosanoids mediate cellular immune response and phenoloxidase reaction to viral infection in adult Pimpla turionellae.

Nodulation is the predominant insect cellular immune response to microbial infections. We posed the hypothesis that parasitoid insects in their adulthood express melanotic nodulation reactions to viral challenge and that eicosanoids mediate nodulation reactions and phenoloxidase (PO) activation in response to viral challenge. To test this idea, we injected Pimpla turionellae adults with indomethacin, a nonsteroidal anti-inflammatory drug, immediately prior to intrahemocoelic injection of Bovine herpes simplex virus-1 (BHSV-1). Treating newly emerged adults of P. turionellae with BHSV-1 induced nodulation reactions, and decreased PO activity at high viral doses. Relative to vehicle-treated controls, indomethacin-treated adults produced significantly reduced numbers of nodules following viral infection (down from approximately 21 nodules per adult to less than six nodules per adult). In addition to injection treatments, increasing dietary indomethacin dosages (from 0.01% to 0.1%) were associated with decreasing nodulation (by six-fold) and PO (by about three-fold) reactions to BHSV-1 injection. Wasp adults orally fed with the lowest dietary indomethacin concentration (0.001%) expressed significantly increased PO activity (1.45 unit/min/mg protein) while nodulation reaction was not affected in response to viral challenge compared to control adults. We infer from these findings that cyclooxygenase (COX) products, at least prostaglandins, mediate nodulation response and PO action to viral infection in adults of these highly specialized insects.

Ecotoxicological effects of dietary titanium dioxide nanoparticles on metabolic and biochemical parameters of model organism Galleria mellonella (Lepidoptera: Pyralidae).

Nanoparticles (NPs) are now being used in many industrial activities, such as mining, paint and glass industries. The frequent industrial use of NPs contributes to environmental pollution and may cause cellular and oxidative damage in native organisms. In this study, the toxic effects of titanium dioxide nanoparticles (TiO2 NPs) were investigated using Galleria mellonella larvae as a model insect species. Alterations in cell damage indicators, such as alanine transferase, aspartate transferase, lactate dehydrogenase, non-enzymatic antioxidants and biochemical parameters, were determined in the hemolymph of G. mellonella larvae exposed to TiO2 NPs at different concentrations (5, 50, 250 and 1250 µg/mL) in their diets. TiO2 NPs caused concentration-dependent cellular damage in the hemolymph of G. mellonella larvae and increased the levels of the non-enzymatic antioxidants uric acid and bilirubin. In addition, total protein in hemolymph significantly decreased at the highest concentration (1250 µg/mL) of TiO2 NPs. Level of the urea increased at the highest concentration (1250 µg/mL) of TiO2 NPs, whereas the amount of glucose was not affected. These findings demonstrated that TiO2 NPs caused concentration-dependent toxic effects on G. mellonella larvae.

Eicosanoids mediate hemolymph oxidative and antioxidative response in larvae of Galleria mellonella L.

Antioxidant enzymes play a major role in the defense against pro-oxidative effects of xenobiotics and pro-oxidant plant allelochemicals in insects. We posed the hypothesis that eicosanoids also mediate antioxidant enzymatic defense reactions to pro-oxidant challenge. To test this idea, we reared first-instar larvae of Galleria mellonella (L.) with the lypoxygenase inhibitor, esculetin (0.001%), the phospholipase A(2) inhibitor, dexamethasone (0.001%) and the dual inhibitor of cyclooxygenase and lipoxygenase, phenidone (0.1%) to seventh-instars. Newly ecdysed seventh-instars were then fed on artificial diet containing 0.05% xanthotoxin (XA) for 2 days. Treating seventh-instar larvae of G. mellonella with XA induced lipid peroxidation and protein carbonylation as evident from the increased content of malondialdehyde (MDA) and protein carbonyls respectively, and antioxidative enzymatic response in a dose-dependent manner. High dietary XA concentrations (0.005 and 0.1%) were associated with increasing MDA and carbonyl content (by 3-fold) and antioxidant enzyme activities, superoxide dismutase (SOD) (by 3-fold) and catalase (CAT) (by 4-fold), and glutathione-dependent enzymes, glutathione S-transferase (GST) (by 15-fold) and glutathione peroxidase (GPx) (by 7-fold). Relative to control, eicosanoid biosynthesis inhibitors (EBIs) esculetin, dexamethasone and phenidone also resulted in impaired MDA content and antioxidant enzyme activities. However, carbonyl content did not differ between control- and EBIs-feeding larvae. Finally, MDA and carbonyl content, and antioxidant enzymes SOD, GST and GPx activities exhibited an incremental increase while CAT activity was decreased in the experimental larvae that had been reared on media amended with esculetin, dexamethasone and phenidone and then challenged with our standard XA challenge dose. Two of the markers indicated that significantly higher levels of oxidative stress were produced in the hemolymph tissue of larvae fed diets supplemented with EBIs and then challenged with XA. This oxidative stress was associated with elicited antioxidative responses by increasing SOD, GST and GPx and decreasing CAT activities in hemolymph. We infer from these findings that eicosanoids mediate insect antioxidant enzymatic responses to dietary pro-oxidants.

The Use of Dietary Antifungal Agent Terbinafine in Artificial Diet and Its Effects on Some Biological and Biochemical Parameters of the Model Organism Galleria mellonella (Lepidoptera: Pyralidae).

Diet quality widely affects the survival, development, fecundity, longevity, and hatchability of insects. We used the greater wax moth Galleria mellonella (Linnaeus) to determine the effects of the antifungal, antibiotic terbinafine on some of its' biological parameters. The effects of terbinafine on malondialdehyde (MDA) and protein carbonyl (PCO) contents and the activity of the detoxification enzyme, glutathione S-transferase (GST), in the midgut of seventh-instar larvae of G. mellonella were also investigated. The insects were reared on an artificial diet containing terbinafine at concentrations of 0.001, 0.01, 0.1, and 1 g. The survival rates at all development stages of G. mellonella were significantly decreased at all terbinafine concentrations. The females from a control diet produced 82.9 ± 18.1 eggs; however, this number was significantly reduced to 51.4 ± 9.6 in females given a 0.1 g terbinafine diet. The highest concentration of terbinafine (1 g) completely inhibited egg laying. Terbinafine significantly increased MDA content and GST activity in the midgut tissue of seventh-instar larvae in a dose-dependent manner. Relative to controls, these low dietary concentrations of terbinafine significantly increased midgut PCO content; a 0.1 g terbinafine concentration raised PCO content from 155.19 ± 21.8 to 737.17 ± 36.4 nmol/mg protein. This study shows concentration-dependent effects on the biological traits of the greater wax moth G. mellonella, including the oxidative status and detoxification capacity of the midgut. Low terbinafine concentrations may be possible for use as an antifungal agent in insect-rearing diets.

Drosophila melanogaster Response to Feeding with Neomycin-Based Medium Expressed in Fluctuating Asymmetry.

The fruit fly Drosophila melanogaster is a model species used for a wide range of studies. Contamination of Drosophila cultures with bacterial infection is common and is readily eradicated by antibiotics. Neomycin antibiotics can cause stress to D. melanogaster's larvae and imagoes, which may affect the interpretation of the results of research using culture from neomycin-based medium. In the present study, fluctuating asymmetry (FA), one of the important bioindicators of stress, was measured. Larvae and imagoes of a wild-type D. melanogaster strain were exposed to various concentrations of neomycin. The size of anal papillae and selected wing veins were measured using scanning electron and light microscopy, respectively. Next, the FA was checked. The values obtained for larval anal papillae appeared to be concentration-dependant; the FA indices increased with the concentration of neomycin. The wing FA presented a large but variable correlation, depending on the measured vein. However, the mean length of veins was the highest for the control group, with neomycin-exposed groups showing lower values. The research showed that neomycin may cause sublethal stress in D. melanogaster, which manifests in increased FA indices. This suggests that neomycin can cause physiological and developmental stress in insects, which should be taken into account when interpreting the results of studies using these model organisms.

Evidence of oxidative and antioxidative responses by Galleria mellonella larvae to malathion.

Antioxidant defense components protect insects by scavenging reactive oxygen species, leading to oxidative stress. I therefore investigated the effects of an organophosphorous insecticide, malathion, on superoxide dismutase (SOD) and acetylcholinesterase (AChE) activities as well as glutathione (GSH) and malondialdehyde (MDA) content as oxidative stress biomarkers in whole body of greater wax moth, Galleria mellonella (L.), larvae. Subcellular fractionation also was assayed for SOD and AChE enzymes to assess subcellular toxicity of malathion in this wax moth. The newly hatched larvae were reared on diets containing 0.01, 0.1, 1.0, and 10 ppm malathion. The diet with lowest concentration of malathion did not significantly influence MDA content and AChE activity. Malathion at 1.0 ppm significantly resulted in increased MDA content and decreased AChE activity. I observed a significant increase in SOD activity, whereas total GSH content and AChE activity were significantly lower for 1.0 ppm malathion than the control groups. Highest concentration of dietary malathion significantly decreased SOD and AChE activities, and GSH content in whole body of the insect. Subcellular fractionations showed that activities of microsomal and soluble AChE, and microsomal SOD for high concentrations of malathion (1.0 and 10 ppm) were significantly lower than control. Soluble SOD activities were significantly increased by low malathion concentrations, whereas only the highest malathion concentration resulted in significantly decreased SOD activity. I infer that induction of antioxidant defense mechanisms in response to increased oxidative stress may be a result of AChE inhibition by malathion in G. mellonella larvae.

Oxidative Effects of Gemifloxacin on Some Biological Traits of Drosophila melanogaster (Diptera: Drosophilidae).

In recent times, several studies have been undertaken on the artificial mass-rearing of insects in which clinical antibacterial antibiotics, including gemifloxacin, which is a DNA gyrase and topoisomerases inhibitor, are amended into the diet to control microbial contamination and preserve diet. The findings of these studies have suggested the possibility that these antibiotics influence the biological traits of insects in relation to their oxidative effects. This study investigated the effects of gemifloxacin on Drosophila melanogaster (Meigen) survival rates, development times, and male-female adult longevity. And we also determined the effects of gemifloxacin on lipid peroxidation product, malondialdehyde, protein carbonyl levels, and glutathione S-transferase activity of fruit fly eggs. First instars were fed on artificial diets containing 150, 300, 600, and 900 mg/liter concentrations of gemifloxacin until adult emergence. Our results indicate that sublethal effects of gemifloxacin are likely to significantly impair adult fitness and life-history parameters in D. melanogaster, probably because of its oxidative effects.

The Effect of Neomycin on Survival and Development of Pimpla turionellae L. (Hymenoptera: Ichneumonidae) Reared on a Natural Host.

Understanding the effects of diet on metabolic events is crucial for biological control programs of parasitoid insects. As bioindicators of long-term physiological stress: survivorship of fifth instar larvae, pupation, adult survival, and developmental time for stages of endoparasitoid Pimpla turionellae L. (Hymenoptera: Ichneumonidae) were investigated by rearing the parasitoid on the host, Galleria mellonella L. (Lepidoptera: Pyralidae) pupae were treated with neomycin. First instar larvae of G. mellonella were reared on artificial diets containing 0.005, 0.01, or 0.5 g neomycin (g/100 g of diet) until seventh instar larvae; the pupae from these larvae were used as a host for rearing P. turionellae. In the control group, the pupae from larvae reared on artificial diets without neomycin were used as a host. Survivorship of fifth instar, pupal, and adult stages of P. turionellae L. reared on G. mellonella pupae as a host fed with different concentrations of neomycin were significantly decreased in comparison to the control group. Approximately eighty percent of P. turionellae L. pupae were produced from control host pupae, while other neomycin concentrations significantly decreased the pupation of the parasitoid. Pimpla turionellae L. larvae reared on control host pupae reached fifth instar in about 9.6 ± 0.61 d, while the larvae reared from a host pupae exposed to the highest antibiotic concentration completed their development to the fifth instar in about 7.4 d. These results showed that neomycin, and possibly its metabolites, contaminated P. turionellae L. larvae from a host and affected larval stages of the parasitoid.

Eicosanoids mediate melanotic nodulation reactions to viral infection in larvae of the parasitic wasp, Pimpla turionellae.

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 inhibitor, 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.

Boric acid-induced effects on protein profiles of Galleria mellonella hemolymph and fat body.

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.