Plasma BDNF and Cytokines Correlated with Protein Biomarkers for Bipolar II Disorder

Abstract

We have previously identified five candidate proteins (matrix metallopeptidase 9 (MMP9), phenylalanyl-TRNA synthetase subunit beta (FARSB), peroxiredoxin 2 (PRDX2), carbonic anhydrase 1 (CA-1), and proprotein convertase subtilisin/kexin Type 9 (PCSK9)) as potential biomarkers for bipolar II disorder (BD-II). These candidate proteins have been associated with neuroprotective factors (BDNF) and inflammatory factors (cytokines, C-reactive protein (CRP), and tumor necrosis factor-α (TNF-α)). However, the correlations between these proteins with plasma BDNF and inflammatory factors remain unknown. We recruited a total of 185 patients with BD-II and 186 healthy controls. Plasma levels of candidate proteins, BDNF, cytokines (TNF-α, CRP, and interleukin-8 (IL-8)) were assessed from each participant. The correlations between levels of candidate proteins, BDNF, and cytokines were analyzed. In the BD-II group, we found that the level of FARSB was positively correlated with the BDNF level (r = 0.397, p < 0.001) and IL-8 (r = 0.320, p < 0.001). The CA-1 level positively correlated with IL-8 (r = 0.318, p < 0.001). In the control group, we found that the FARSB level positively correlated with the BDNF level (r = 0.648, p < 0.001). The CA-1 level positively correlated with TNF-α (r = 0.231, p = 0.002), while the MMP-9 level positively correlated with the CRP level (r = 0.227, p = 0.002). Our results may help in clarifying the underlying mechanism of these candidate proteins for BD-II.

Levels of Matrix Metalloproteinase 9 Are Elevated in Persons With Schizophrenia or Bipolar Disorder: The Role of Modifiable Factors

“…There are fewer studies looking at MMP-9 blood levels in persons with bipolar disorder than in schizophrenia, and these studies have inconsistent findings. In bipolar disorder, no differences in MMP-9 serum levels were found in a study of mood-stabilized persons with bipolar disorder compared with control participants ( 36 ) or in another small bipolar disorder sample ( 37 ), but elevated MMP-9 levels were reported in persons with acute bipolar depression ( 38 ) and in those with bipolar disorder, all of whom had bipolar II disorder ( 39 ). It is of note that in our study the odds ratios of MMP-9 levels associated with bipolar disorder were substantially lower than those in individuals with schizophrenia.…”

Brain Derived Neurotrophic Factor (BDNF) as a Biological Factor in a Personalized Approach that Affects the Effectiveness of the Treatment of Patients with Substance Dependence

“…Полиморфизм rs6265 гена BDNF связан с повышенным риском развития и тяжестью протекания аффективного биполярного расстройства [42], большой депрессии [43], шизофрении [44], различных тревожных расстройств [45], ранней деменции [46]. В исследовании с общей выборкой из 796 пациентов с большим депрессивным расстройством установлено, что полиморфизм в гене BDNF связан с увеличением суицидального поведения при назначении селективных ингибиторов обратного захвата серотонина [43].…”