In contrast to humans, extensive fat reserves do not make brown bears sick, report Viennese researchers. Generous amounts of “good cholesterol” (HDL) and “antioxidants” protect you from harmful effects if you equip yourself with rich energy reserves for hibernation. Petz’s metabolic strategies could possibly be used to combat arteriosclerosis in people, they explain in the specialist magazine “Scientific Reports”.
A team led by Sylvain Giroud from the Research Institute for Wildlife Science and Ecology at the University of Veterinary Medicine, Vienna examined the cholesterol metabolism and blood values of free-living European brown bears (Ursus arctos), which had devoured large reserves of fat in order not to starve to death during hibernation. During this time, their fat metabolism changed radically, the researchers explain in a broadcast. However, various counter-mechanisms kept the animals healthy despite high blood lipid levels.
New strategies possible
For example, an enzyme in the bear’s body that stabilizes HDL cholesterol becomes hyperactive. It is considered good cholesterol because, unlike LDL cholesterol, it does not cause hardening of the arteries (atherosclerosis). In addition, the animals have more “antioxidants” in their blood. They protect the body from harmful substances (free oxygen radicals), which occur more frequently when the fat content is excessive and which damage the muscles and promote inflammation.
These protective measures allow the bears to eat masses of fat that would make people sick. In these, among other things, arteriosclerosis would be triggered, and deposits and inflammatory processes would develop on the inner wall of the coronary vessels, carotid arteries and the leg arteries. This can lead to circulatory disorders in the legs (intermittent claudication) and medical emergencies such as heart attacks and strokes. With the findings from the brown bear metabolism, new strategies against arteriosclerosis in humans could perhaps be developed, the researchers write. (apa)
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