Serum level of brain-derived neurotrophic factor in Parkinson's disease: a meta-analysis

Abstract

Brain-derived neurotrophic factor (BDNF), a critical modulator in the neurodevelopment and maintenance of both central and peripheral nervous systems, is regarded as a potential therapeutic target of Parkinson's disease (PD). However, its association with PD remains unclear and the data are inconsistent. To explore the correlation, studies reporting BDNF levels in PD patients and healthy controls are searched and a sample of 1496 participants are pooled in the meta-analysis, demonstrating significantly decreased serum levels of BDNF in PD patients when compared with the healthy controls (SMD = -1.03; 95% CI [-1.83, -0.23]; P = .012). Meta-regression analysis indicates gender is an important confounding factor (Adj R = 69.20%, p = .004, I res = 90.64%), whereas age (Adj R = 11.91%, P = .95, I res = 96.86%), H-Y stages of PD progression (Adj R = -30.18%, P = .612, I res = 96.62%) and MoCA score assessed cognitive impairment (Adj R = 2.18%, P = .517, I res = 64.41%) show few moderating effects. The research provides evidence of moderate quality that blood levels of BDNF are decreased in PD patients despite various influencing factors, supporting an association between decreased level of peripheral BDNF and PD.

Evaluation of Biochemical and Epigenetic Measures of Peripheral Brain-Derived Neurotrophic Factor (BDNF) as a Biomarker in Huntington’s Disease Patients

“…Other studies have shown that BDNF levels in plasma are different between females and males (Lommatzsch et al, 2005); however, we did not find significant sex differences in plasma BDNF in our cohort, regardless of disease status. We did detect significant positive correlations between both plasma and salivary BDNF and age, which is in contrast to previous studies in the literature that have found either no effect (Jiang et al, 2019) or modest decreased levels of BDNF with age in blood (Lommatzsch et al, 2005;Ziegenhorn et al, 2007). Importantly, however, we did not find that age was a significant covariate in analyzing the differences in BDNF levels between HD patients and controls.…”

Plasma Exosomal Brain-Derived Neurotrophic Factor Correlated with the Postural Instability and Gait Disturbance–Related Motor Symptoms in Patients with Parkinson’s Disease

“…BDNF is presumed to be responsible for the survival and repair of neurons, and low plasma BDNF has been thought to be related to neurodegenerative diseases. However, plasma BDNF was found to be elevated, reduced, or identical in patients with PD compared with controls, as demonstrated by a recent meta-analysis conducted by Jiang et al [10]. This inconsistency was also noted by research on the association between BDNF and AD [27].…”

“…Blood BDNF has also been investigated for its possible role as a biomarker for PD. Blood BDNF was assumed to be lower in patients with PD than in controls because of the nature of neurodegenerative diseases; however, prior research found heterogenicity to be remarkable [10]. Moreover, the blood BDNF level is dynamic and is affected by numerous environmental factors [7].…”

Actions of Brain-Derived Neurotrophin Factor in the Neurogenesis and Neuronal Function, and Its Involvement in the Pathophysiology of Brain Diseases

“…However, a large-scale study in which over 600 individuals were participated concluded that significant decrease of serum BDNF levels were observed in patients with AD, frontotemporal dementia, Lewy body dementia, vascular dementia whereas significant increase was confirmed in PD patients [ 139 ]. On the other hand, the latest study of the meta-analysis indeed supports an association between decreased blood concentration of BDNF and PD [ 140 ].…”