Erschienen in:International Journal of Alzheimer's Disease
Sprache:
Englisch
DOI:
10.1155/2012/604141
ISSN:
2090-8024;
2090-0252
Entstehung:
Anmerkungen:
Beschreibung:
<jats:p>The present study was aimed at assessing the capability of A<jats:italic>β</jats:italic>1-40 and A<jats:italic>β</jats:italic>1-42 levels in undiluted plasma (UP), diluted plasma (DP), and cell bound (CB) to distinguish between early stages of Alzheimer's disease (AD), amnesic mild cognitive impairment (MCI), and healthy control (HC). Four blood samples from each participant were collected during one month and the levels of A<jats:italic>β</jats:italic>1-40 and A<jats:italic>β</jats:italic>1-42 were determined by a blinded proprietary ELISA sandwich (Araclon Biotech. Zaragoza, Spain). First striking result was that the amount of A<jats:italic>β</jats:italic>1-40 and A<jats:italic>β</jats:italic>1-42 in UP represented only a small proportion (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mrow><mml:mo>~</mml:mo><mml:mn>15</mml:mn><mml:mo>%</mml:mo></mml:mrow></mml:math>) of the total beta-amyloid pool in blood (<jats:italic>β</jats:italic>APB) described here as the sum of A<jats:italic>β</jats:italic>1-40 and A<jats:italic>β</jats:italic>1-42 in blood where they are free in plasma, bound to plasma proteins, and bound to blood cells. Furthermore, we found that levels of A<jats:italic>β</jats:italic>1-40 and A<jats:italic>β</jats:italic>1-42 in UP, DP, and CB were significantly higher in MCI when compared to HC. On average, the total<jats:italic>β</jats:italic>APB was 1.8 times higher in MCI than in HC (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M2"><mml:mi>P</mml:mi><mml:mo>=</mml:mo><mml:mn>0.03</mml:mn></mml:math>) and allowed to discriminate between MCI and HC with a sensitivity and specificity over 80%. Thus, quantification of several markers of the<jats:italic>β</jats:italic>APB could be useful and reliable in the discrimination between MCI and HC.</jats:p>