Most cited article - PubMed ID 22085825
Adipokinetic hormone-induced antioxidant response in Spodoptera littoralis
The primary aim of this study was to analyse the influence of honeybee venom on various aspects of Drosophila melanogaster physiology and to assess the efficacy of adipokinetic hormone (AKH) in mitigating venom toxicity. We examined the harmful effects of venom on the thoracic muscles and central nervous system of Drosophila, as well as the potential use of AKH to counteract these effects. The results demonstrated that envenomation altered AKH levels in the Drosophila CNS, promoted cell metabolism, as evidenced by an increase in citrate synthase activity in muscles, and improved relative cell viability in both organs incubated in vitro. Furthermore, venom treatment reduced the activity of two key antioxidative stress enzymes, superoxide dismutase and catalase, and modified the expression of six genes encoding immune system components (Keap1, Relish, Nox, Eiger, Gadd45, and Domeless) in both organs. The venom also disrupted muscle cell ultrastructure, specifically myofibrils, and increased the release of arginine kinase into the incubation medium. Notably, when administered alongside the venom, AKH influenced the majority of these changes. AKH was the most effective in minimising damage to the ultrastructure of muscle cells and preventing the release of arginine kinase from muscles to the medium; however, in other parameters, the effect was modest or minimal. Given that honeybee venom often affects humans, understanding its actions and potential ways to reduce or eliminate them is valuable and could lead to the development of pharmacologically important compounds that may have clinical relevance.
- Keywords
- Adipokinetic hormone, Arginine kinase, Bee venom, Drosophila model, Immune responsible genes, Muscle structure,
- MeSH
- Central Nervous System drug effects metabolism MeSH
- Drosophila melanogaster drug effects metabolism MeSH
- Insect Hormones * pharmacology metabolism MeSH
- Pyrrolidonecarboxylic Acid * analogs & derivatives pharmacology metabolism MeSH
- Oligopeptides * pharmacology metabolism MeSH
- Bee Venoms * toxicity antagonists & inhibitors MeSH
- Bees MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Names of Substances
- adipokinetic hormone MeSH Browser
- Insect Hormones * MeSH
- Pyrrolidonecarboxylic Acid * MeSH
- Oligopeptides * MeSH
- Bee Venoms * MeSH
Insect adipokinetic hormones (AKHs) are neuropeptides with a wide range of actions, including the control of insect energy metabolism. These hormones are also known to be involved in the insect defence system against toxins and pathogens. In this study, our aim was to demonstrate whether the application of external AKHs significantly enhances the efficacy of the entomopathogenic fungus Isaria fumosorosea in a model species (firebug Pyrrhocoris apterus) and pest species (Egyptian cotton leafworm Spodoptera littoralis and pea aphid Acyrthosiphon pisum). It was found that the co-application of Isaria with AKHs significantly enhanced insect mortality in comparison to the application of Isaria alone. The mode of action probably involves an increase in metabolism that is caused by AKHs (evidenced by the production of carbon dioxide), which accelerates the turnover of Isaria toxins produced into the infected insects. However, several species-specific differences probably exist. Intoxication by Isaria elicited the stimulation of Akh gene expression and synthesis of AKHs. Therefore, all interactions between Isaria and AKH actions as well as their impact on insect physiology from a theoretical and practical point of view need to be discussed further.
- Keywords
- AKH, carbon dioxide production, entomopathogen, insect pest, metabolism, mortality,
- Publication type
- Journal Article MeSH
Insects, like other organisms, must deal with a wide variety of potentially challenging environmental factors during the course of their life. An important example of such a challenge is the phenomenon of oxidative stress. This review summarizes the current knowledge on the role of adipokinetic hormones (AKH) as principal stress responsive hormones in insects involved in activation of anti-oxidative stress response pathways. Emphasis is placed on an analysis of oxidative stress experimentally induced by various stressors and monitored by suitable biomarkers, and on detailed characterization of AKH's role in the anti-stress reactions. These reactions are characterized by a significant increase of AKH levels in the insect body, and by effective reversal of the markers-disturbed by the stressors-after co-application of the stressor with AKH. A plausible mechanism of AKH action in the anti-oxidative stress response is discussed as well: this probably involves simultaneous employment of both protein kinase C and cyclic adenosine 3',5'-monophosphate pathways in the presence of extra and intra-cellular Ca(2+) stores, with the possible involvement of the FoxO transcription factors. The role of other insect hormones in the anti-oxidative defense reactions is also discussed.
- Keywords
- AKH gene, FoxO, adipokinetic hormones (AKH), anti-oxidative mechanisms, free radicals, insect endocrine system, insecticide, oxidative stress, signaling pathway,
- MeSH
- Insecta metabolism MeSH
- Insect Hormones metabolism MeSH
- Pyrrolidonecarboxylic Acid analogs & derivatives metabolism MeSH
- Oligopeptides metabolism MeSH
- Oxidative Stress * MeSH
- Signal Transduction MeSH
- Animals MeSH
- Check Tag
- Animals MeSH
- Publication type
- Journal Article MeSH
- Research Support, Non-U.S. Gov't MeSH
- Review MeSH
- Names of Substances
- adipokinetic hormone MeSH Browser
- Insect Hormones MeSH
- Pyrrolidonecarboxylic Acid MeSH
- Oligopeptides MeSH