Hawkmoths use nectar sugar to reduce oxidative damage from flight
E Levin1, G Lopez-Martinez2, B Fane3
1Department of Entomology, University of Arizona, Tucson, AZ, USA. levineran1@gmail.com.
Science (New York, N.Y.)
|February 18, 2017
Summary
Nectar-feeding moths use sugar to reduce flight muscle damage. They shunt glucose via the pentose phosphate pathway (PPP) to generate antioxidant potential, enabling high metabolic rates and powerful flight.
Area of Science:
- Metabolic physiology
- Insect flight biomechanics
- Biochemistry
Background:
- Nectarivores exhibit high metabolic rates, necessitating efficient energy utilization.
- Intense aerobic activity, like flight, induces oxidative stress in muscles.
- Nectar, a primary food source, offers minimal antioxidant compounds.
Purpose of the Study:
- To investigate if nectar sugar mitigates flight-induced oxidative muscle damage in nectarivores.
- To explore the metabolic pathways involved in antioxidant production from nectar sugar.
Main Methods:
- Comparative analysis of oxidative damage in flight muscles of sugar-fed versus unfed moths.
- Respirometry and stable isotope (δ13C) analyses to track glucose metabolism.
- Assessment of antioxidant potential generated through metabolic shunting.
Main Results:
- Sugar-fed moths displayed significantly lower oxidative damage to flight muscle membranes compared to unfed moths.
- Moths utilize nectar glucose, shunting it to the pentose phosphate pathway (PPP).
- This metabolic process generates antioxidant potential, reducing muscle oxidative stress.
Conclusions:
- Nectar sugar serves as a crucial resource for mitigating exercise-induced oxidative damage in moths.
- The pentose phosphate pathway (PPP) plays a key role in antioxidant generation from nectar.
- Nectar feeding, PPP utilization, and intense exercise are evolutionarily linked, facilitating the development of powerful nectarivorous fliers.
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