PMID- 30296429 OWN - NLM STAT- MEDLINE DCOM- 20200211 LR - 20200211 IS - 1872-6240 (Electronic) IS - 0006-8993 (Linking) VI - 1704 DP - 2019 Feb 1 TI - Plasma levels of brain-derived neurotrophic factor in patients with Parkinson disease: A systematic review and meta-analysis. PG - 127-136 LID - S0006-8993(18)30510-9 [pii] LID - 10.1016/j.brainres.2018.10.006 [doi] AB - BACKGROUND: Brain-derived neurotrophic factor (BDNF) is an abundant neurotrophin in the adult brain. Serum BDNF levels might be used as a proxy for its central expression. Considering conflicting reports, we aimed to answer "How do serum/CSF levels of BDNF change in patients with PD?". METHODS: We conducted a comprehensive search in MEDLINE, EMBASE and SCOPUS databases including 12 eligible studies. Five studies compared BDNF in serum of PD patients versus healthy controls (HC) and 3 studies provided BDNF levels in sera of non-depressed and depressed PD patients (NDPD and DPD). Review Manager and Software version 3.0 were used for meta-analysis and meta-regressions. Mean difference (MD) was used for measurement of effect size. RESULTS: PD patients had reduced serum BDNF levels compared to HC (MD = -2.99 ng/mL). Serum BDNF was highest in DPD patients compared to HC (MD = -4.83 ng/mL), with no difference between DPD and NDPD patients in serum BDNF levels. Among co-variates that were eligible for meta-regression, age, sex, and Hoehn and Yahr (H&Y) motor stage had significant positive associations with the effect size in the difference of serum BDNF between patients and HC. CONCLUSIONS: PD patients had reduced serum BDNF levels compared to HC, regardless of presence of co-morbid depression. PD is at least equally effective in reducing serum BDNF levels as depression. Motor progression predicts serum BDNF downregulation in PD. Acute exercise improves motor function and depressive symptoms in PD probably via BDNF upregulation. The paradoxical rise in serum BDNF in advance PD is probably compensatory in nature. CI - Copyright (c) 2018. Published by Elsevier B.V. FAU - Rahmani, Farzaneh AU - Rahmani F AD - Students Scientific Research Center, Tehran University of Medical Sciences, Tehran, Iran; NeuroImaging Network (NIN), Universal Scientific Education and Research Network (USERN), Tehran, Iran. FAU - Saghazadeh, Amene AU - Saghazadeh A AD - Systematic Review and Meta-analysis Expert Group (SRMEG), Universal Scientific Education and Research Network (USERN), Tehran, Iran. FAU - Rahmani, Maryam AU - Rahmani M AD - Students Scientific Research Center, Tehran University of Medical Sciences, Tehran, Iran. FAU - Teixeira, Antonio L AU - Teixeira AL AD - Department of Psychiatry and Behavioral Sciences, The University of Texas Health Science Center at Houston, Houston, TX, USA; Laboratorio Interdisciplinar de Investigacao Medica, Faculdade de Medicina, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, Brazil. FAU - Rezaei, Nima AU - Rezaei N AD - NeuroImaging Network (NIN), Universal Scientific Education and Research Network (USERN), Boston, USA; Research Center for Immunodeficiencies, Pediatrics Center of Excellence, Children's Medical Center, Tehran University of Medical Sciences, Tehran, Iran; Department of Immunology, School of Medicine, Tehran University of Medical Sciences, Tehran, Iran. FAU - Aghamollaii, Vajiheh AU - Aghamollaii V AD - Department of Neurology, Roozbeh Hospital, Tehran University of Medical Sciences, Roozbeh Hospital, Tehran, Iran. Electronic address: V-aghamollaii@sina.tums.ac.ir. FAU - Ardebili, Hassan Eftekhar AU - Ardebili HE AD - Department of Health Education and Promotion, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Electronic address: eftkhara@tums.ac.ir. LA - eng PT - Journal Article PT - Meta-Analysis PT - Systematic Review DEP - 20181006 PL - Netherlands TA - Brain Res JT - Brain research JID - 0045503 RN - 0 (Brain-Derived Neurotrophic Factor) SB - IM MH - Brain-Derived Neurotrophic Factor/*blood MH - Depressive Disorder/blood/complications MH - Disease Progression MH - Humans MH - Parkinson Disease/*blood/complications OTO - NOTNLM OT - BDNF OT - Brain-derived neurotrophic factor OT - Depression OT - Hoehn and Yahr OT - Parkinson disease OT - Serum EDAT- 2018/10/09 06:00 MHDA- 2020/02/12 06:00 CRDT- 2018/10/09 06:00 PHST- 2018/08/18 00:00 [received] PHST- 2018/10/03 00:00 [revised] PHST- 2018/10/04 00:00 [accepted] PHST- 2018/10/09 06:00 [pubmed] PHST- 2020/02/12 06:00 [medline] PHST- 2018/10/09 06:00 [entrez] AID - S0006-8993(18)30510-9 [pii] AID - 10.1016/j.brainres.2018.10.006 [doi] PST - ppublish SO - Brain Res. 2019 Feb 1;1704:127-136. doi: 10.1016/j.brainres.2018.10.006. Epub 2018 Oct 6.