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Dietary alpha-ketoglutarate partially prevents age-related decline in locomotor activity and cold tolerance in Drosophila melanogaster

  • Maria M. Bayliak EMAIL logo , Maria P. Lylyk and Oksana M. Sorochynska
Published/Copyright: April 28, 2017
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Biologia
From the journal Biologia Volume 72 Issue 4

Abstract

Alpha-ketoglutarate (AKG), a key intermediate in the Krebs cycle and metabolism of amino acids, is one of dietary supplements studied actively during last decade. In this work, we examined the ability of dietary AKG to prevent age-related functional decline in D. melanogaster. For that, some metabolic processes and physiological functions, such as climbing activity and cold resistance, were studied in young (2 days post-eclosion) and middle-aged (24 days) D. melanogaster w1118 adults maintained on AKG-supplemented diet. Both locomotor activity and cold resistance measured as chill coma recovery time (CCRT) impaired in middle-aged flies compared with young ones. Diet with 10 mM AKG improved climbing activity in middle-aged flies of both sexes. A positive impact of AKG on CCRT was found in young flies of both sexes and in middle-aged females. AKG-containing diet did not affect cold hardening in young flies, whereas middle-aged flies fed on AKG were more resistant to repeated cold treatments than control ones. Two-day old flies reared on AKG had higher free amino acid level, including that of proline. At 24-day age, AKG-fed females but not males had higher levels of free amino acids and glucose, and higher total antioxidant capacity than control ones. We conclude that both the enhancement of antioxidant capacity and synthesis of amino acids can contribute to AKG-promoted reduction in CCRT. However, since dietary AKG enhanced locomotor activity and resistance to repeated cold stresses in middle-aged both males and females, mechanisms of beneficial effects of AKG seem to be more complicated, that is discussed.

Key words: amino acids; total antioxidant capacity; glucose; functional senescence; stress resistance

Acknowledgements

We are grateful to Bloomington Stock Center (Indiana University, USA) for providing D. melanogaster strain, Ms. U. Dzaman for English editing of the manuscript, O. Semchyshyn, O. Manyuch, and H. Shmihel for technical assistance.

  1. Conflict of interest: The authors have declared that there is no conflict of interest.

Abbreviations

ABTS

2,2’-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt

AKG

alpha-ketoglutarate

CCRT

chill coma recovery time

ROS

reactive oxygen species

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Received: 2016-10-12
Accepted: 2017-1-25
Published Online: 2017-4-28
Published in Print: 2017-4-25

© 2017 Institute of Zoology, Slovak Academy of Sciences

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https://doi.org/10.1515/biolog-2017-0042
Keywords for this article
amino acids; total antioxidant capacity; glucose; functional senescence; stress resistance

Articles in the same Issue

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  2. Occurrence of Anaplasma phagocytophilum in three sympatric tick species in the South Moravia, Czech Republic
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  7. Botany
  8. Transcriptome analysis in leaves of rice (Oryza sativa) under high manganese stress
  9. Botany
  10. Type II metacaspase protein localization and gene transcription during programmed cell semi-death of sieve elements in developing caryopsis of Tritium aestivum
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  12. Environmental factors determining the distribution pattern of leeches (Clitellata: Hirudinida) in large river systems: A case study of the Oder River system
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  16. Bioassessment of streams based on macroinvertebrates — can sampling of some substrate types be excluded?
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