Changes in lipid and carbohydrate metabolism during starvation in adult Manduca sexta

Ziegler, Rolf

doi:10.1007/bf00262874

Cited by 91 publications

(68 citation statements)

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“…Female M. sexta often mix nectar foraging and oviposition bouts on host plants with nectar-rich flowers [e.g., Datura (48)] and derive a 10-fold fitness benefit in number of eggs matured when they consume nectar as adults (49). The observation that female M. sexta lay more eggs on plants with experimentally enhanced nectar volumes (50) prompted Kessler and Baldwin (51) to suggest that females use nectar as a proxy measure of host-plant quality.…”

Section: Context Dependence Of Female Responses In Binary-choice Assaysmentioning

confidence: 99%

Context- and scale-dependent effects of floral CO ₂ on nectar foraging by Manduca sexta

Goyret

Markwell²,

Raguso³

2008

Proc. Natl. Acad. Sci. U.S.A.

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fragrance ͉ odor ͉ olfaction ͉ pollination ͉ Sphingidae A nthophilous insects use information from a variety of sensory channels to locate flowers and feed from them (1). Thus, a crucial task for studying insect-plant interactions is to identify which components of the environment provide the sensory inputs used by insects, and to what extent context and scale affect their information content (2). Whereas flower colors and patterns (3, 4), whole-flower and nectar odors (5), and even corolla shape and texture are known features used by foraging insects and other nectivorous animals (6, 7), few studies have explicitly addressed the role of flower respiratory carbon dioxide (CO 2 ) as a stimulus involved in plant-pollinator interactions.Our knowledge of how insects use CO 2 as a sensory cue is derived primarily from studies of insects that vector diseases or attack crop plants. For example, many haematophagous insects use CO 2 to locate their animal hosts from a distance (8). Discontinuous CO 2 plumes modulate host-seeking behavior by mosquitoes (9, 10), suggesting that CO 2 acts as a long-range orientation stimulus (11). Tsetse flies and biting midges also use CO 2 as a long-range attractant that can synergize the attractiveness of other host odors (12, 13). However, CO 2 also functions as a close-range feeding stimulus (on the host's skin) for mosquitoes (8). CO 2 synergizes the attractiveness of some human skin odors to female yellow fever mosquitoes (14) and has been suggested to synergize triatomine bug responses to L(ϩ)-lactic acid (15).Some herbivorous insects show similar responses to CO 2 , although typically at closer range to its source than haematophagous insects. CO 2 alone is sufficient to guide Diabrotica virgifera beetle larvae toward corn roots (16), and larvae of noctuid (Helicoverpa armigera) (17) and pyralid (Elasmopalpus lignosellus) (18) moths orient to above-ambient CO 2 sources. Females of the pyralid moth Cactoblastis cactorum search for CO 2 sinks on photosynthetic stem surfaces of Opuntia stricta, as indicators of high carbon fixation activity (19). In this case, CO 2 gradients are used as close-range stimuli, as is true for tephritid flies that oviposit on fruit wounds, which provide a localized source of CO 2 and other olfactory oviposition stimulants (20). Finally, responses to CO 2 may be context-dependent. Tephritid flies respond to CO 2 when presented with a fruit-like visual stimulus (20). Within a certain concentration range, Drosophila melanogaster adults and larvae are repelled by CO 2 , and it has been suggested that these responses depend on the olfactory context (21).It is clear from the studies reviewed above that CO 2 may function alone or in concert with host odors, at a distance or at close range, via several behavioral mechanisms. Recent studies suggest that CO 2 may also contribute to the interactions between flowers and insect pollinators. Floral CO 2 is primarily associated with elevated respiratory activity in thermogenic flowers, including deceptive flowers that mim...

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Section: Context Dependence Of Female Responses In Binary-choice Assaysmentioning

confidence: 99%

Context- and scale-dependent effects of floral CO ₂ on nectar foraging by Manduca sexta

Goyret

Markwell²,

Raguso³

2008

Proc. Natl. Acad. Sci. U.S.A.

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“…According to Dimitrios et al (2003), their short-term impact in the form of psychological, physiological, or environmental stimuli activates an organism to induce neurohormonal regulatory mechanisms, which leads to homeostasis. In turn, animals that have been chronically exposed to stress are characterized by higher susceptibility to pathogens, which represents the effect of reducing the adjustment mechanisms (Kock et al, 1987;Ziegler, 1991).…”

Section: Introductionmentioning

confidence: 99%

The application of mesenchymal progenitor stem cells for the reduction of oxidative stress in animals

Wojtas¹,

Zachwieja²,

Zwyrzykowska³

et al. 2017

Turk J Biol

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IntroductionEvery cell in both humans and livestock is involved in oxidation-reduction reactions. Their main products are oxygen free radicals, molecules having at least one unpaired electron in their structure (Betteridge, 2000;Czajka, 2006;Uttara et al., 2009). Under normal conditions, an organism seeking the balance equilibrium removes reactive compounds using protective substances and enzymes. Disturbances that occur in the accumulation of these are referred to as oxidative stress (Nisar et al., 2013;Konvičná et al., 2015).The organism is exposed to oxidative stress especially when subjected to intense physical and metabolic exertion. In the case of livestock, oxidative stress occurs as the result of continuous improvement and sharp selection in order to increase productivity (Jóźwik et al., 2012). According to Kimothi and Ghosh (2005), interracial mating is an alternative for alleviating the effects of oxidative stress, but research results of another author (Tanaka et al., 2008) did not confirm the above dependence.Metabolic disorders increase the incidence of oxidative stress. In dairy cows, the predisposing factor is dietary mistakes committed in the last few months of lactation and in the dry period (Blowey, 2005). In addition, fat increased mobilization from the subcutaneous tissue in the perinatal period leads to increased production of lipid peroxide and reactive oxygen species (Konvičná et al., 2015), which contributes to a reduction in the antioxidant capacity of an organism in early lactation (Turk et al., 2005). Similar results were observed in sheep and goats (El-Deeb, 2015).The oxidation-antioxidant imbalance may be an effect of 'stressor' activity. According to Dimitrios et al. (2003), their short-term impact in the form of psychological, physiological, or environmental stimuli activates an organism to induce neurohormonal regulatory mechanisms, which leads to homeostasis. In turn, animals that have been chronically exposed to stress are characterized by higher susceptibility to pathogens, which represents the effect of reducing the adjustment mechanisms (Kock et al., 1987;Ziegler, 1991).An innovative method of oxidative stress reducing in animals can be an application of stem cells, which are isolated from bone marrow, peripheral blood, and umbilical cord or adipose tissue. Mesenchymal stem cells (MSCs) have an ability of rapid multiplication, tissue repair, and regeneration. Moreover, MSCs can exhibit an immunosuppressive effect. According to Gala et al. (2010), an important feature of MSCs is their ability to synthesize and secrete cytokines. From the immunological point of view, cytokine proteins produced by leukocytes affect the Abstract: Oxidative stress is the primary cause of lowering of the body's immune status. It arises as a result of intense metabolic processes in humans and animals that involve a decrease in antioxidant enzymes activity at the expense of increased production of free radicals and reactive oxygen species (ROS). Consequently, this leads to oxidation of lipids, protein...

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“…During the larval period (ϳ20 days), the content of TG in the fat body increases from a few micrograms to ϳ80 mg (2). During subsequent development, the lipid reserves are used to sustain the life of the adult insect, which feeds occasionally (2)(3)(4)(5). Due to these metabolic features, M. sexta represents an excellent model for studying the basic mechanisms involved in either the synthesis/deposition of TG in larvae or the mobilization of TG in adult insects (moth).…”

mentioning

confidence: 99%

Activation of the Lipid Droplet Controls the Rate of Lipolysis of Triglycerides in the Insect Fat Body

Patel

Soulages

Hariharasundaram

et al. 2005

Journal of Biological Chemistry

102

127

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The hydrolysis of triglyceride (TG) stored in the lipid droplets of the insect fat body is under hormonal regulation by the adipokinetic hormone (AKH), which triggers a rapid activation cAMP-dependent kinase cascade (protein kinase A (PKA)). The role of phosphorylation on two components of the lipolytic process, the TG-lipase and the lipid droplet, was investigated in fat body adipocytes. The activity of purified TG-lipase determined using in vivo TG-radiolabeled lipid droplets was unaffected by the phosphorylation of the lipase. However, the activity of purified lipase was 2.4-fold higher against lipid droplets isolated from hormone-stimulated fat bodies than against lipid droplets isolated from unstimulated tissue. In vivo stimulation of lipolysis promotes a rapid phosphorylation of a lipid droplet protein with an apparent mass of 42-44 kDa. This protein was identified as "Lipid Storage Droplet Protein 1" (Lsdp1). In vivo phosphorylation of this protein reached a peak ϳ10 min after the injection of AKH. Supporting a role of Lsdp1 in lipolysis, maximum TG-lipase activity was also observed with lipid droplets isolated 10 min after hormonal stimulation. The activation of lipolysis was reconstituted in vitro using purified insect PKA and TG-lipase and lipid droplets. In vitro phosphorylation of lipid droplets catalyzed by PKA enhanced the phosphorylation of Lsdp1 and the lipolytic rate of the lipase, demonstrating a prominent role PKA and protein phosphorylation on the activation of the lipid droplets. AKH-induced changes in the properties of the substrate do not promote a tight association of the lipase with the lipid droplets. It is concluded that the lipolysis in fat body adipocytes is controlled by the activation of the lipid droplet. This activation is achieved by PKA-mediated phosphorylation of the lipid droplet. Lsdp1 is the main target of PKA, suggesting that this protein is a major player in the activation of lipolysis in insects.Insects rely on lipid reserves to survive during physiological non-feeding periods or to meet the energy requirements of developing eggs, flight, and starvation. The fat body is the principal site for storage of both glycogen and lipids. The fat body synthesizes most of the proteins found in the hemolymph while also serving as the main storage site of triglycerides (TG), 1 which constitute Ͼ90% fat body lipids. Therefore, functionally, the fat body accomplishes roles that in vertebrates are carried out by both liver and adipose tissue (1).The tobacco hornworm, Manduca sexta, feeds constantly, and the content of fat body TG increases continuously until the end of the larval development. During the larval period (ϳ20 days), the content of TG in the fat body increases from a few micrograms to ϳ80 mg (2). During subsequent development, the lipid reserves are used to sustain the life of the adult insect, which feeds occasionally (2-5). Due to these metabolic features, M. sexta represents an excellent model for studying the basic mechanisms involved in either the synthesis/deposition o...

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Changes in lipid and carbohydrate metabolism during starvation in adult Manduca sexta

Cited by 91 publications

References 8 publications

Context- and scale-dependent effects of floral CO ₂ on nectar foraging by Manduca sexta

Context- and scale-dependent effects of floral CO ₂ on nectar foraging by Manduca sexta

The application of mesenchymal progenitor stem cells for the reduction of oxidative stress in animals

Activation of the Lipid Droplet Controls the Rate of Lipolysis of Triglycerides in the Insect Fat Body

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Changes in lipid and carbohydrate metabolism during starvation in adult Manduca sexta

Cited by 91 publications

References 8 publications

Context- and scale-dependent effects of floral CO 2 on nectar foraging by Manduca sexta

Context- and scale-dependent effects of floral CO 2 on nectar foraging by Manduca sexta

The application of mesenchymal progenitor stem cells for the reduction of oxidative stress in animals

Activation of the Lipid Droplet Controls the Rate of Lipolysis of Triglycerides in the Insect Fat Body

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Product

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Context- and scale-dependent effects of floral CO ₂ on nectar foraging by Manduca sexta

Context- and scale-dependent effects of floral CO ₂ on nectar foraging by Manduca sexta