Yeshiva大学Albert Einstein医学院研究人员发现一种使人长寿的突变基因——CETP VV,还可以帮助老年人清晰思路,保持记忆。研究结果刊登于12月26日《Neurology》杂志。
由Einstein医学院老龄化研究所Nir Barzilai博士率领的研究小组,对158名95岁及以上的东欧犹太血统老年人和先前证实没有此突变基因的老年人进行标准认知功能测试,发现脑功能很好的老年人中,有此突变基因的老年人是没有此突变基因的老年人的二倍。
接下来,研究人员在124名年龄在75-85岁的犹太血统老年志愿者中验证,发现非痴呆老年人中,具有此突变基因的老年人数量是未有此突变基因老年人数量的5倍。
Barzilai博士及其同事先前发现CETP VV有助于延年益寿,并且能够世代传递。“好”的高密度脂蛋白和“坏”的低密度脂蛋白会聚集为脂蛋白颗粒(lipoprotein particles),胆甾醇酯蛋白影响颗粒大小。CETP VV突变改变了胆甾醇酯蛋白。百岁老人中,具有CETP VV的人数占75%,而且携带CETP VV的老年人明显具有较大的脂蛋白颗粒。
研究人员认为比较大的脂蛋白颗粒很难在血管中停留。因此,携带CETP VV的人群(能够产生较大脂蛋白颗粒)发生心脏病和中风的机率很小,似乎能够解释他们非同寻常长寿的原因。
新研究结果提示CETP VV不仅能够延年益寿,还能够保护大脑认知功能的完整性。CETP VV或者经过抗血管堵塞("anti-clogging")预防心脏病发作和中风,或者经过一种尚未发现的独立的保护机制。
“大脑功能不良,活到100岁也并不是一件幸事,”Barzilai博士说,“我们发现能够帮助延年益寿的同一种基因突变还有助于这些老年人清晰思路。”CETP VV很可能是防止阿尔茨海莫氏症发生的原因。对这些百岁老人研究,也许可以找到他们抵制这些在其他老年人中常见的疾病,为预防/治疗年龄相关疾病提供线索。
英文原文:
Gene tied to longevity also preserves ability to think clearly
December 25, 2006 -- (Bronx, NY) -- A gene variant linked to living a very long life--to 90 and beyond--also serves to help very old people think clearly and retain their memories, according to new research by scientists at the Albert Einstein College of Medicine of Yeshiva University. Their findings are published in the December 26, 2006 issue of Neurology.
Led by Dr. Nir Barzilai, director of the Institute for Aging Research at Einstein, the researchers examined 158 people of Ashkenazi (Eastern European) Jewish descent who were 95 or older. Compared with elderly subjects lacking the gene variant, those who possessed it were twice as likely to have good brain function based on a standard test of cognitive function.
Later the researchers validated their findings independently in a younger group of 124 Ashkenazi Jews between the ages of 75 and 85 who were enrolled in the Einstein Aging Study led by Dr. Richard Lipton. Within this group, those who did not develop dementia at follow up were five times more likely to have the favorable genotype than those who developed dementia.
Dr. Barzilai and his colleagues had previously shown that this gene variant helps people live exceptionally long lives and apparently can be passed from one generation to the next. Known as CETP VV, the gene variant alters the Cholesterol Ester Protein. This protein affects the size of "good" HDL and "bad" LDL cholesterol, which are packaged into lipoprotein particles. Centenarians were three times likelier to possess CETP VV compared with a control group representative of the general population and also had significantly larger HDL and LDL lipoproteins than people in the control group.
Researchers believe that larger cholesterol particles are less likely to lodge themselves in blood vessels. So people with the CETP VV gene (and the larger cholesterol particles they produce) run a lower risk of heart attacks and strokes, which may explain their unusual longevity.
The findings of this new study suggest that CETP VV also protects the cognitive integrity of the brain--either through the same vascular "anti-clogging" benefit that prevents heart attacks and strokes or through an independent protective mechanism that remains to be found.
"Without good brain function, living to age 100 is not an attractive proposition," says Dr. Barzilai. "We've shown that the same gene variant that helps people live to exceptional ages has the added benefit of helping them think clearly for most of their long lives. It's possible that CETP VV's cognitive effect is to protect against the development of Alzheimer's disease. In studying these centenarians, we hope to learn why they're able to resist diseases that affect the general population at a much younger age. This knowledge should greatly aid our efforts to prevent or delay the onset of age-related diseases."