Background: There is great interest in developing blood-based biomarkers for Alzheimer’s disease (AD);however, there is no consensus as to what blood fraction is most appropriate for analyzing particular markers. The...Background: There is great interest in developing blood-based biomarkers for Alzheimer’s disease (AD);however, there is no consensus as to what blood fraction is most appropriate for analyzing particular markers. The current study provides empirical evidence regarding how blood-based proteins vary depending on whether they are assayed in serum or plasma. Methods: Weanalyzed concentrations of 100 proteins in matched samples of serum and plasma from 39 Caucasian AD participants from the Texas Alzheimer’s Research and Care Consortium bymultiplex immunoassay. Results: Concentrations of 40 proteins were highly correlated (r2≥ 0.75) between plasma and serum while the remaining proteins were moderately to weakly correlated (r2< 0.75). Discussion: Whether plasma vs. serum is assayed can have a large impact on the observed concentration of some proteins, including several proteins that are of great interest to AD pathophysiology. The current findings may explain the significant discrepancies often times reported in the AD biomarker field.展开更多
Background: Depression is often viewed as a risk factor for the development of Alzheimer's disease (AD), however little is known regarding the underlying biological mechanisms linking these two diseases. Brain-der...Background: Depression is often viewed as a risk factor for the development of Alzheimer's disease (AD), however little is known regarding the underlying biological mechanisms linking these two diseases. Brain-derived neurotrophic factor (BDNF) has been linked to both cognitive impairment and depression in past research;however few studies have ex-amined this relation in a sample of Alzheimer's patients. The present study sought to address this gap in the literature by examining the relation between serum BDNF levels and depression assessed by the Geriatric Depression Scale (GDS) in a group of patients diagnosed with probable Alzheimer's disease. Methods: Participants included 169 individuals diagnosed with Probable AD enrolled in the TARC Longitudinal Research Cohort with available BDNF levels and GDS scores. The participants were divided into Depressed (N = 20) and Not Depressed (N = 149) based on GDS scores. Re-sults: BDNF levels significantly predicted level (High vs. Low) of depression (β = 0.066, SE = 0.031, p = 0.034). BDNF levels for the Depressed group were significantly higher than those observed in the Not Depressed group (p. > 0.036). Conclusions: These findings suggest that an upregulation of BDNF possibly exists among depressed AD patients as a response to the chronic inflammatory processes that occur in depression. This upregulation of BDNF appears to persist at least into early stages of Alzheimer's.展开更多
文摘Background: There is great interest in developing blood-based biomarkers for Alzheimer’s disease (AD);however, there is no consensus as to what blood fraction is most appropriate for analyzing particular markers. The current study provides empirical evidence regarding how blood-based proteins vary depending on whether they are assayed in serum or plasma. Methods: Weanalyzed concentrations of 100 proteins in matched samples of serum and plasma from 39 Caucasian AD participants from the Texas Alzheimer’s Research and Care Consortium bymultiplex immunoassay. Results: Concentrations of 40 proteins were highly correlated (r2≥ 0.75) between plasma and serum while the remaining proteins were moderately to weakly correlated (r2< 0.75). Discussion: Whether plasma vs. serum is assayed can have a large impact on the observed concentration of some proteins, including several proteins that are of great interest to AD pathophysiology. The current findings may explain the significant discrepancies often times reported in the AD biomarker field.
文摘Background: Depression is often viewed as a risk factor for the development of Alzheimer's disease (AD), however little is known regarding the underlying biological mechanisms linking these two diseases. Brain-derived neurotrophic factor (BDNF) has been linked to both cognitive impairment and depression in past research;however few studies have ex-amined this relation in a sample of Alzheimer's patients. The present study sought to address this gap in the literature by examining the relation between serum BDNF levels and depression assessed by the Geriatric Depression Scale (GDS) in a group of patients diagnosed with probable Alzheimer's disease. Methods: Participants included 169 individuals diagnosed with Probable AD enrolled in the TARC Longitudinal Research Cohort with available BDNF levels and GDS scores. The participants were divided into Depressed (N = 20) and Not Depressed (N = 149) based on GDS scores. Re-sults: BDNF levels significantly predicted level (High vs. Low) of depression (β = 0.066, SE = 0.031, p = 0.034). BDNF levels for the Depressed group were significantly higher than those observed in the Not Depressed group (p. > 0.036). Conclusions: These findings suggest that an upregulation of BDNF possibly exists among depressed AD patients as a response to the chronic inflammatory processes that occur in depression. This upregulation of BDNF appears to persist at least into early stages of Alzheimer's.
