Seals’ bodies switch fuel usage as they begin diving
By ANISunday, June 6, 2010
WASHINGTON - The Weddell seal’s body switches fuel usage as the animal turns into a diver from a non-diving pup, a new American research shows.
The study, conducted by Baylor University biologists, is the first to show that an animal has the ability to switch what type of fuels they burn in their muscles.
The study appears in the Journal of Experimental Biology.
Dr. Stephen Trumble, assistant professor of biology at Baylor in the College of Arts and Sciences, said: “This is truly a remarkable finding.
“From some of our previous work, we found that certain physiological characteristics in the swimming muscles of these animals change with age like myoglobin, fiber type and some aerobic and anaerobic enzymes. Now, it certainly seems the cellular function also is changing such that the seals oxidize fuels slower and more efficiently. This is key because it allows them to forge longer and survive in one of the harshest environments on the planet.”
The Baylor study looked at 50 Weddell seals as they aged from pups to mature adults. The researchers took muscles biopsies and analysed how the muscles burn fuel.
The study found as the seals mature from a non-diving pup to a mature adult, they gradually switch from using saturated fatty acids in their skeletal muscle for fuel to polyunsaturated fatty acids like omega-3s.
Trumble said researchers noticed a switch beginning when the seal is approximately one-year old.
The researchers believe that this switch may be a cellular trigger to initiate diving because there is a strong link between skeletal muscle lipid composition and lipids in the membrane of the muscle and cellular metabolism.
The long-range implications of the Baylor study could help researchers unlock mysteries related to human conditions as well, Trumble said.
He said: “Another part of this is we know that membrane physiology and its composition are essential for the normal development of the brain, and numerous studies have shown that there is a link between insulin resistance, lipid composition of the skeletal membrane and many diseases involving obesity, hypertension and cardiovascular issues.
“So, if we can discover how these seals switch from utilizing one fuel over another in the muscle then we may provide some insight on why we suffer from specific health related problems.” (ANI)
