Alzheimer’s Diseases: Towards Biomarkers for an Early Diagnosis

Changes in methylation patterns of multiple genes from peripheral blood leucocytes of Alzheimer's disease patients

“…In the present studies, not only the hypomethylation of APP gene but also the significant increase of its gene expression in the leucocytes of AD patients was observed and both were consistent with previous observations in AD patients or aged brain 28 , 29 , 4 . In contrast to hypermethylation, hypomethylation always could activate gene transcription.…”

“…As a limitation in the diagnostic sensitivity and specificity of various tests, there is no single diagnostic test for AD. As recently proposed, diagnosis of AD is still based on the integration of clinical examination, neuropsychological data, radiological and biological analyses with biomarkers for the disease 4 . As for these testings, biomarkers are increasingly used in the research setting to detect onset of the disease and to track progression 5 .…”

“…As for these testings, biomarkers are increasingly used in the research setting to detect onset of the disease and to track progression 5 . During the past years, great efforts have been made to identify reliable biomarkers in body fluids for AD patients, which are suitable for minimal invasion early diagnosis of AD, mainly from cerebrospinal fluid (CSF) and blood 4 . CSF closely reflects the composition of the brain extracellular space and is likely to have the highest yield for biomarkers 6 .…”

“…The CSF collection by lumbar puncture is an invasive, expensive and time-consuming procedure; therefore, the detection of biomarker molecules in blood would be more accessible. Nonetheless, in comparison with CSF biomarkers, discovering reliable biomarkers for AD in peripheral blood has not been successful and has not been a solid diagnostic method 4 . Therefore, exploring some interesting biomarkers and establishing convenient techniques with low cost, rapid and high accuracy which could be used routinely in clinical diagnosis are still important goals for all researchers.…”