Genetic association study reveals impact of interleukin 10 polymorphisms on cognitive functions in schizophrenia.

AIM: Cognitive deficits are the core factors impacting quality of life among patients diagnosed with schizophrenia. Effective method of treatment for this domain of symptoms remains lacking. Recent evidence suggests the link between impaired cognition and aberrant inflammatory response. Severity of symptoms might be linked to individual genetic predispositions and single-nucleotide polymorphisms (SNPs) in genes encoding interleukins and their receptors. Current genetic association studies include anti-inflammatory interleukins, such as IL10. Functional polymorphisms of IL10 (rs1800871, rs18008729) have been indicated to affect information processing in schizophrenia. MATERIALS AND METHODS: In this study, we analyzed the potential impact of 27 functional SNPs in 8 cytokine genes on cognitive parameters measured by Wisconsin card-sorting test (WCST) in schizophrenia group (n = 150) and healthy controls (n = 152). RESULTS: We found significant associations of two functional polymorphisms of IL10 (rs1800871, rs1800872) and WCST results. Allele A carriers in rs1800871 performed significantly better in Percent of Conceptual Level Responses (CLR%). Allele A carriers in rs1800871 and allele T carriers in rs1800872 obtained better results in Completed Categories (CC). The impact of illness duration was observed, with better performance of recent-onset patients. CONCLUSIONS: Results of this study indicate that genetic variants of inflammatory response are associated with cognitive deficits in schizophrenia. The role of cytokines in schizophrenia need to be investigated in the aspect of pro-/anti-inflammatory imbalance. Altered inflammatory response promote chronic mild inflammation in the brain and aberrant synaptic plasticity.

A Lack of Correlation between Brain-Derived Neurotrophic Factor Serum Level and Verbal Memory Performance in Healthy Polish Population.

Brain derived neurotrophic factor (BDNF) is considered to be connected with memory and learning through the processes of long term synaptic potentiation and synaptic plasticity. The aim of the study was to examine the relationship between precursor BDNF (proBNDF) and mature BDNF (mBDNF) serum levels and performance on Rey Auditory-Verbal Learning Test (RAVLT) in 150 healthy volunteers. In addition, we have verified the relationships between serum concentration of both forms of BDNF and RAVLT with sociodemographic and lifestyle factors.We found no strong evidence for the correlation of proBDNF and mBDNF serum levels with performance on RAVLT in healthy Polish population in early and middle adulthood. We observed the mBDNF serum concentration to be higher in women compared with men. Moreover, we revealed higher mBDNF level to be connected with lower body mass index (BMI). In turn, the results of RAVLT correlated with sociodemographic and lifestyle factors, such as: age, education, gender, BMI and smoking.

BDNF gene polymorphisms and haplotypes in relation to cognitive performance in Polish healthy subjects.

The brain derived neurotrophic factor (BDNF) is a neurotrophin that plays an important role in the cell survival, axonal and dendritic growth, and synaptic plasticity. BDNF gene polymorphisms, 'functional Val66Met mainly, were shown to influence human brain structure and cognition. The aim of the study was to assess the relationship between twelve BDNF gene variants and their haplotypes and cognitive performance measured using the Wisconsin Card Sorting Test (WCST), the Trail Making Test (TMT), the Stroop Test which are to a large extent connected with prefrontal cortex activity. Our sample consisted of 460 healthy participants from Polish population. We detected possible association between five BDNF polymorphisms (rs11030101, rs10835210, rs2049046, rs2030324, rs2883187) and TMT_A. Additionally, one haplotype block made from eleven BDNF variants (rs2883187, rs1401635, rs2049046, rs2030324, rs11030101, rs10835210, rs1013402, rs1401635, rs1013402), as significant linkage disequilibrium appeared. We discovered possible relationships of CACCGCGTACG and CACCGCGTACG haplotypes with TMT_A and TMT_B performance respectively. Our results confirmed the involvement of BDNF in the regulation of psychomotor speed, working memory and executive function in healthy subjects measured by a task engaging visuoperceptual abilities.