【分享】研究指肥胖還會造成大腦退化

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很多人知道肥胖會增加患糖尿病、心臟病的危險。美國科學家最新發現，肥胖還會加速大腦退化，這意味著肥胖人群罹患老人癡呆的機率較高。這是科學家首次發現肥胖會對大腦造成損害。

新華網報導，美國加州大學洛杉磯分校神經學家選擇九十四名七十歲以上老人作為研究對象。這些老人身體健康，不存在認知水平下降問題。

研究人員以「身高體重指數」”ＢＭＩ”為標準，將這些人分成正常體重、超重和肥胖３組，再透過掃描實驗對象大腦發現，體重超出正常範圍越多，腦組織退化越嚴重，肥胖人群的腦組織比體重正常者平均少８％。認知能力也因此受到影響。

研究人員說，肥胖加劇了大腦的老化速度，「肥胖人群的大腦看起來比精瘦者老１６年，而超重者則老８年」。

這篇今天看到的新聞讓我想到

昨天才在TIMES上面看到的用降膽固醇藥治療Alzheimer's Disease

大家可以想一想之間的關聯性

A Heart Drug May Hold Off Alzheimer's

In a study of 110 elderly volunteers, aged 65 to 79, who donated their brains for research and whose cognitive functions were monitored over several years prior to their death, scientists led by Dr. Eric Larson of the Group Health Center for Health Studies found that those who had taken statin drugs to lower their cholesterol had fewer nerve-damaging plaques and tangles — protein deposits that form in and around neurons — in their brains than those not taking the medications. Buildup of these protein plaques and tangles are the hallmark of Alzheimer's disease; they inexorably disrupt the critical connections between neurons that govern thought processes and sabotage everything from the storage and retrieval of memories to learning and language skills.

The new findings are the latest and most definitive results linking the popular statin drugs to Alzheimer's. Earlier studies had produced conflicting results: some found that statins reduced the risk of the brain disorder, while others found no effect. Larson's study is the first to directly compare the brains, on autopsy, of statin users and non-users (Alzheimer's can be conclusively diagnosed only after death, when pathologists confirm the presence of the plaques and tangles in the brain). "This data does give us some additional hope that statins may turn out to have a useful relationship in slowing Alzheimer's disease," says William Thies, vice president of medical and scientific relations of the Alzheimer's Association.

How do cholesterol-lowering drugs work on the brain? As experts learn more about Alzheimer's, they believe that it's less a disease of the brain than of the vasculature, or blood vessel system. It turns out that many of the risk factors for Alzheimer's are the same ones for heart disease, and that the build up of protein in the brain is not unlike the gradual accumulation of plaque in the heart vessels. "We are learning that Alzheimer's disease isn't just plaques and tangles appearing through a series of biochemical processes, but that vascular stress may play a role in their development," says Larson. "Anything we can do to lower the vascular risk profile could lower the risk of Alzheimer's." Statins, then, could be inhibiting the development of Alzheimer's by keeping the brain's neural highways free of potentially bottlenecking protein plaques. In addition, says Larson, statins may be working on a more molecular level, by actually blocking the formation of the sticky, fibrous tangles that can jam nerve connections.

To learn more about exactly how statins could be thwarting the Alzheimer's disease process, Larson acknowledges that the first step involves having another, independent group replicate his team's findings. In the meantime, he plans to continue his study by adding more volunteers. Within the next year, Thies expects two more trials to produce results and hopefully solidify the effect statins have on the brain.

肥胖會造成心血管方面的疾病

尤其是plaque(跟膽固醇累積有關)

而文中指出心血管的plaque和大腦老化所堆積的plaque又很相近