Plasma carnitine in fasting neonatal and adult northern elephant seals

1992 ◽  
Vol 263 (3) ◽  
pp. E570-E574
Author(s):  
S. H. Adams ◽  
D. P. Costa ◽  
S. C. Winter
Keyword(s):  
Fatty Acid ◽  
Acid Oxidation ◽  
Mirounga Angustirostris ◽  
Elephant Seals ◽  
Plasma Carnitine ◽  
Adult Females ◽  
Naturally Occurring ◽  
Northern Elephant Seals ◽  
Free Fatty Acid Oxidation ◽  
The Impact

Maintenance of adequate body carnitine stores is a requisite for fasting mammals, whose energy is derived mainly from free fatty acid oxidation. The impact of longterm fasting on carnitine status is unclear, and there have been no reports of carnitine during naturally occurring fasts. Total (TC), free (FC), and acylated (AC) plasma carnitine levels were determined in 10 weaned and 11 adult northern elephant seals (Mirounga angustirostris) during natural fasts lasting from 1 to 3 mo. In pups, TC declined little and AC increased only slightly [P greater than 0.05, analysis of variance (ANOVA)] through 11 wk of fasting. Plasma FC dropped by 53 and 26% from week 1 values at 10 and 11 wk fasting, respectively (P = 0.014, ANOVA). The AC/FC ratio did not approach 1.0 until 7 wk of fasting. TC was 38.6 +/- 1.4 microM and 47.6 +/- 4.1 microM in adult females and males, respectively. Adult AC/FC ratios were 0.71 +/- 0.10 (females) and 0.08 +/- 0.04 (males). Plasma TC status is not negatively affected by extended fasting in adult and weaned northern elephant seals. These data support the hypothesis that fasting northern elephant seals defend plasma TC and maintain an attenuated AC/FC ratio well into their prolonged natural fast.

Characterization of blubber fatty acid signatures in northern elephant seals (Mirounga angustirostris) over the postweaning fast

2013 ◽  
Vol 183 (8) ◽  
pp. 1065-1074 ◽  
Author(s):  
Dawn P. Noren ◽  
Suzanne M. Budge ◽  
Sara J. Iverson ◽  
Michael E. Goebel ◽  
Daniel P. Costa ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Mirounga Angustirostris ◽  
Elephant Seals ◽  
Northern Elephant Seals

scholarly journals The rise and fall of dialects in northern elephant seals

2018 ◽  
Vol 285 (1892) ◽  
pp. 20182176 ◽  
Author(s):  
Caroline Casey ◽  
Colleen Reichmuth ◽  
Daniel P. Costa ◽  
Burney Le Boeuf
Keyword(s):  
Mammalian Species ◽  
Structural Complexity ◽  
Mirounga Angustirostris ◽  
Geographical Differences ◽  
Migration Patterns ◽  
Elephant Seals ◽  
The North ◽  
Vocal Behaviour ◽  
Northern Elephant Seals ◽  
The North Pacific

Vocal dialects are fundamental to our understanding of the transmission of social behaviours between individuals and populations, however few accounts trace this phenomenon among mammals over time. Northern elephant seals ( Mirounga angustirostris ) provide a rare opportunity to examine the trajectory of dialects in a long-lived mammalian species. Dialects were first documented in the temporal patterns of the stereotyped vocal displays produced by breeding males at four sites in the North Pacific in 1968 and 1969, as the population recovered from extreme exploitation. We evaluated the longevity of these geographical differences by comparing these early recordings to calls recently recorded at these same locations. While the presence of vocal dialects in the original recordings was re-confirmed, geographical differences in vocal behaviour were not found at these breeding rookeries nearly 50 years later. Moreover, the calls of contemporary males displayed more structural complexity after approximately four generations, with substantial between-individual variation and call features not present in the historical data. In the absence of measurable genetic variation in this species—owing to an extreme population bottleneck—a combination of migration patterns and cultural mutation are proposed as factors influencing the fall of dialects and the dramatic increase in call diversity.

scholarly journals Acetylation and succinylation contribute to maturational alterations in energy metabolism in the newborn heart

2016 ◽  
Vol 311 (2) ◽  
pp. H347-H363 ◽  
Author(s):  
Arata Fukushima ◽  
Osama Abo Alrob ◽  
Liyan Zhang ◽  
Cory S. Wagg ◽  
Tariq Altamimi ◽  
...  
Keyword(s):  
Fatty Acid ◽  
Energy Metabolism ◽  
Fatty Acid Oxidation ◽  
Glucose Oxidation ◽  
Acid Oxidation ◽  
Amino Acid Synthesis ◽  
Oxidation Rates ◽  
Cardiac Energy Metabolism ◽  
Cardiac Energy ◽  
The Impact

Dramatic maturational changes in cardiac energy metabolism occur in the newborn period, with a shift from glycolysis to fatty acid oxidation. Acetylation and succinylation of lysyl residues are novel posttranslational modifications involved in the control of cardiac energy metabolism. We investigated the impact of changes in protein acetylation/succinylation on the maturational changes in energy metabolism of 1-, 7-, and 21-day-old rabbit hearts. Cardiac fatty acid β-oxidation rates increased in 21-day vs. 1- and 7-day-old hearts, whereas glycolysis and glucose oxidation rates decreased in 21-day-old hearts. The fatty acid oxidation enzymes, long-chain acyl-CoA dehydrogenase (LCAD) and β-hydroxyacyl-CoA dehydrogenase (β-HAD), were hyperacetylated with maturation, positively correlated with their activities and fatty acid β-oxidation rates. This alteration was associated with increased expression of the mitochondrial acetyltransferase, general control of amino acid synthesis 5 like 1 (GCN5L1), since silencing GCN5L1 mRNA in H9c2 cells significantly reduced acetylation and activity of LCAD and β-HAD. An increase in mitochondrial ATP production rates with maturation was associated with the decreased acetylation of peroxisome proliferator-activated receptor-γ coactivator-1α, a transcriptional regulator for mitochondrial biogenesis. In addition, hypoxia-inducible factor-1α, hexokinase, and phosphoglycerate mutase expression declined postbirth, whereas acetylation of these glycolytic enzymes increased. Phosphorylation rather than acetylation of pyruvate dehydrogenase (PDH) increased in 21-day-old hearts, accounting for the low glucose oxidation postbirth. A maturational increase was also observed in succinylation of PDH and LCAD. Collectively, our data are the first suggesting that acetylation and succinylation of the key metabolic enzymes in newborn hearts play a crucial role in cardiac energy metabolism with maturation. Listen to this article’s corresponding podcast at http://ajpheart.podbean.com/e/acetylation-control-of-energy-metabolism-in-newborn-hearts/ .

Effect of maternal canine starvation on fetal and neonatal liver metabolism

1981 ◽  
Vol 240 (2) ◽  
pp. E88-E94
Author(s):  
E. L. Miettinen
Keyword(s):  
Fatty Acid ◽  
Free Fatty Acid ◽  
Glucose Concentration ◽  
Acid Oxidation ◽  
Hepatic Glycogen ◽  
Uridine Diphosphate ◽  
Nadh Ratio ◽  
Free Fatty Acid Oxidation ◽  
Diphosphate Glucose ◽  
Neonatal Liver

Heptic glycolytic and gluconeogenic intermediates from fasted newborns of five control and five 3-day starved canine mothers (MCS) were studied at 0, 3, 6, 9, and 24 h of age. MCS did not affect fetal hepatic glycogen concentration; however, a significant increase in uridine diphosphate glucose (UDPG) (0.186 vs. 0.106 mumol/g), fructose 6-phosphate (0.084 vs. 0.034), pyruvate (0.321 vs. 0.126), and citrate (0.190 vs. 0.140) concentrations occurred. At 3 h, the intrahepatic glucose concentration among the MCS newborns declined (3.09 vs. 6.34) and remained lower than the controls for up to 9 h. UDPG concentration, however, remained elevated throughout the 24 h. In addition intrahepatic pyruvate was significantly elevated in the MCS group. Elevated phosphoenolpyruvate concentrations were observed between 3 and 6 h. Malate levels were lower than controls between 6 and 9 h and alpha-ketoglutarate was significantly higher between 6 and 24 h. Calculated cytoplasmic NAD/NADH ratio was elevated throughout the 24 h. Hepatic triglycerides were higher than controls up to 9 h. A decline in hepatic triglycerides was observed between 9 and 24 h. The results suggest increased glycolysis and suppressed gluconeogenesis in the MCS puppies, probably because of increased triglyceride synthesis and decreased free fatty acid oxidation resulting in a lack of cytoplasmic NADH.

The effect of rehabilitation of northern elephant seals (Mirounga angustirostris) on antimicrobial resistance of commensal Escherichia coli

2009 ◽  
Vol 133 (3) ◽  
pp. 264-271 ◽  
Author(s):  
Robyn A. Stoddard ◽  
E. Rob Atwill ◽  
Patricia A. Conrad ◽  
Barbara A. Byrne ◽  
Spencer Jang ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Mirounga Angustirostris ◽  
Elephant Seals ◽  
Northern Elephant Seals

scholarly journals Weight Reduction and the Impaired Plasma-Derived Free Fatty Acid Oxidation in Type 2 Diabetic Subjects1

2001 ◽  
Vol 86 (4) ◽  
pp. 1638-1644
Author(s):  
E. E. Blaak ◽  
B. H. R. Wolffenbuttel ◽  
W. H. M. Saris ◽  
M. M. A. L. Pelsers ◽  
A. J. M. Wagenmakers
Keyword(s):  
Fatty Acid ◽  
Free Fatty Acid ◽  
Fatty Acid Oxidation ◽  
Weight Reduction ◽  
Acid Oxidation ◽  
Free Fatty Acid Oxidation ◽  
Type 2 Diabetic

scholarly journals Rival assessment among northern elephant seals: evidence of associative learning during male–male contests

2015 ◽  
Vol 2 (8) ◽  
pp. 150228 ◽  
Author(s):  
Caroline Casey ◽  
Isabelle Charrier ◽  
Nicolas Mathevon ◽  
Colleen Reichmuth
Keyword(s):  
Communication Strategy ◽  
Social Knowledge ◽  
Mirounga Angustirostris ◽  
Alternative Communication ◽  
Elephant Seals ◽  
Acoustic Signatures ◽  
Dominance Relationships ◽  
Northern Elephant Seals ◽  
Rival Assessment ◽  
Male Contests

Specialized signals emitted by competing males often convey honest information about fighting ability. It is generally believed that receivers use these signals to directly assess their opponents. Here, we demonstrate an alternative communication strategy used by males in a breeding system where the costs of conflict are extreme. We evaluated the acoustic displays of breeding male northern elephant seals ( Mirounga angustirostris ), and found that social knowledge gained through prior experience with signallers was sufficient to maintain structured dominance relationships. Using sound analysis and playback experiments with both natural and modified signals, we determined that males do not rely on encoded information about size or dominance status, but rather learn to recognize individual acoustic signatures produced by their rivals. Further, we show that behavioural responses to competitors' calls are modulated by relative position in the hierarchy: the highest ranking (alpha) males defend their harems from all opponents, whereas mid-ranking (beta) males respond differentially to familiar challengers based on the outcome of previous competitive interactions. Our findings demonstrate that social knowledge of rivals alone can regulate dominance relationships among competing males within large, spatially dynamic social groups, and illustrate the importance of combining descriptive and experimental methods when deciphering the biological relevance of animal signals.

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