title: Adipocytokines and CD34 progenitor cells in Alzheimer's disease.
abstract: BACKGROUND
  Alzheimer's disease (AD) and atherosclerosis share common vascular risk factors such as arterial hypertension and hypercholesterolemia. Adipocytokines and CD34(+) progenitor cells are associated with the progression and prognosis of atherosclerotic diseases. Their role in AD is not adequately elucidated.
  
  
  RESULTS
  In the present study, we measured in 41 patients with early AD and 37 age- and weight-matched healthy controls blood concentrations of adiponectin and leptin by enzyme linked immunoabsorbent assay and of CD34(+) progenitor cells using flow cytometry. We found significantly lower plasma levels of leptin in AD patients compared with the controls, whereas plasma levels of adiponectin did not show any significant differences (AD vs. control (mean ± SD): leptin:8.9 ± 5.6 ng/mL vs.16.3 ± 15.5 ng/mL;P = 0.038; adiponectin:18.5 ± 18.1 µg/mL vs.16.7 ± 8.9 µg/mL;P = 0.641). In contrast, circulating CD34(+) cells were significantly upregulated in AD patients (mean absolute cell count ± SD:253 ± 51 vs. 203 ± 37; P = 0.02) and showed an inverse correlation with plasma levels of leptin (r =  -0.248; P = 0.037). In logistic regression analysis, decreased leptin concentration (P = 0.021) and increased number of CD34(+) cells (P = 0.036) were both significantly associated with the presence of AD. According to multifactorial analysis of covariance, leptin serum levels were a significant independent predictor for the number of CD34(+) cells (P = 0.002).
  
  
  CONCLUSIONS
  Our findings suggest that low plasma levels of leptin and increased numbers of CD34(+) progenitor cells are both associated with AD. In addition, the results of our study provide first evidence that increased leptin plasma levels are associated with a reduced number of CD34(+) progenitor cells in AD patients. These findings point towards a combined involvement of leptin and CD34(+) progenitor cells in the pathogenesis of AD. Thus, plasma levels of leptin and circulating CD34(+) progenitor cells could represent an important molecular link between atherosclerotic diseases and AD. Further studies should clarify the pathophysiological role of both adipocytokines and progenitor cells in AD and possible diagnostic and therapeutic applications.
authors.affiliation: Medizinische Klinik III, Kardiologie und Kreislauferkrankungen, Eberhard-Karls-Universität Tübingen, Tübingen, Germany.
authors.forename: Boris
authors.initials: B
authors.lastname: Bigalke
authors.forename: Brigitte
authors.initials: B
authors.lastname: Schreitmüller
authors.forename: Kateryna
authors.initials: K
authors.lastname: Sopova
authors.forename: Angela
authors.initials: A
authors.lastname: Paul
authors.forename: Elke
authors.initials: E
authors.lastname: Stransky
authors.forename: Meinrad
authors.initials: M
authors.lastname: Gawaz
authors.forename: Konstantinos
authors.initials: K
authors.lastname: Stellos
authors.forename: Christoph
authors.initials: C
authors.lastname: Laske
mesh_terms: D052242:Adiponectin / Q000097:blood*; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000097:blood* / Q000473:pathology; D018952:Antigens, CD34 / Q000097:blood; D002452:Cell Count; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005434:Flow Cytometry; D006412:Hematopoietic Stem Cells / Q000166:cytology* / Q000378:metabolism; D006801:Humans; D020738:Leptin / Q000097:blood*; D016015:Logistic Models; D008297:Male; D008875:Middle Aged
chemical_list: D052242:Adiponectin; D018952:Antigens, CD34; D020738:Leptin