想过没有，浑身脂肪的北极熊为何不死于心血管疾病?
科学家找到答案。尽管北极熊体内的脂肪组织比例高达50%，且LDL及甘油三脂水平也很高，但由于北极熊的基因APOB有些改变，能使胆固醇转出血液进入细胞而利用，因而不因体脂过多而患上心血管疾病。论文发表在Cell。
FILE - Taiga the polar bear looks on at the Quebec Aquarium in Quebec City, Quebec, Canada, Dec. 30, 2013
Their diet allows for a body fat build-up for insulation and buoyancy while swimming. But it comes at a cost - very high levels of LDL cholesterol, known as the "bad cholesterol," and triglycerides in the blood. They have levels that would cause cardiovascular disease in humans, but their genetic changes seem to have taken care of the problem.
One important example was a change in the gene APOB, which plays a role in getting cholesterol out of the bloodstream and into cells, thereby lowering heart disease risk.
"This all makes very good sense in a species which is completely reliant on fat for survival," Lorenzen said.
The study was published on Thursday in the journal Cell.
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谷歌今天为纪念英国女化学家霍奇金诞生104周年，画的是她测的青霉素分子模型。她因测定维生素B12的分子结构于1964年获得诺贝尔奖，成为第三位女性诺贝尔奖获得者。但她最重要的工作则是测定胰岛素的结构。
