Subject(s)
Hallucinations/physiopathology , Pulvinar/physiopathology , Schizophrenia/physiopathology , Self-Control , Volition/physiology , Adult , Female , Hallucinations/diagnostic imaging , Hallucinations/etiology , Humans , Magnetic Resonance Imaging , Pulvinar/diagnostic imaging , Schizophrenia/complications , Schizophrenia/diagnostic imaging , Young AdultABSTRACT
Recent studies demonstrate that brain-derived neurotrophic factor (BDNF) might be associated with nicotine addiction, and circulating BDNF is a biomarker of memory and general cognitive function. Moreover, studies suggest that a functional polymorphism of the BDNF Val66Met may mediate hippocampal-dependent cognitive functions. We aimed to explore the relationships between smoking, cognitive performance and BDNF in a normal Chinese Han population. We recruited 628 male healthy subjects, inducing 322 smokers and 306 nonsmokers, and genotyped them the BDNF Val66Met polymorphism. Of these, we assessed 114 smokers and 98 nonsmokers on the repeatable battery for the assessment of neuropsychological status (RBANS), and 103 smokers and 89 nonsmokers on serum BDNF levels. Smokers scored lower than the nonsmokers on RBANS total score (p = 0.002), immediate memory (p = 0.003) and delayed memory (p = 0.021). BDNF levels among the smokers who were Val allele carriers were correlated with the degree of cognitive impairments, especially attention, as well as with the carbon monoxide concentrations. Our findings suggest that smoking is associated with cognitive impairment in a male Chinese Han population. The association between higher BDNF levels and cognitive impairment, mainly attention in smokers appears to be dependent on the BDNF Val66Met polymorphism.
Subject(s)
Brain-Derived Neurotrophic Factor/genetics , Cognition/drug effects , Smoking/adverse effects , Adult , Aged , Alleles , Asian People/genetics , Brain-Derived Neurotrophic Factor/metabolism , Cognition/physiology , Cognition Disorders/genetics , Cognition Disorders/physiopathology , Cognitive Dysfunction/genetics , Cognitive Dysfunction/physiopathology , Gene Frequency/genetics , Genetic Predisposition to Disease , Genotype , Humans , Male , Memory/drug effects , Middle Aged , Polymorphism, Single Nucleotide/genetics , Smoking/genetics , Smoking/metabolism , Tobacco Smoking/adverse effects , Tobacco Smoking/genetics , Tobacco Use Disorder/geneticsABSTRACT
OBJECTIVE: Recent evidence suggests the role of brain-derived neurotrophic factor (BDNF) in the pathophysiology of suicidal behavior. Because schizophrenia patients usually have high suicide rates and numerous studies have suggested that BDNF may contribute to the psychopathology of schizophrenia, we hypothesized that the functional polymorphism of BDNF (Val66Met) was associated with suicide attempts in patients with schizophrenia in a Chinese Han population. METHOD: This polymorphism was genotyped in 825 chronic schizophrenia patients with (n = 123) and without (n = 702) suicide attempts and 445 healthy controls without a history of suicide attempts using a case-control design. The schizophrenia symptoms were assessed by the Positive and Negative Syndrome Scale. RESULTS: There were no significant differences in BDNF Val66Met genotype and allele distributions between the patients and healthy controls. However, we found the Val allele (p = .023) and the Val/Val genotypes (p = .058) to be associated with a history of suicide attempts. Moreover, some clinical characteristics, including age and cigarettes smoked each day, interacted with the BDNF gene variant and appeared to play an important role in suicide attempts among schizophrenia patients. CONCLUSIONS: The BDNF Val66Met polymorphism itself and its interaction with some clinical variables may influence suicide attempts among schizophrenia patients. (PsycINFO Database Record
