BDNF CpG methylation and serum levels covary during alcohol withdrawal in patients with alcohol use disorder: A pilot study

ObjectivesBrain-derived neurotrophic factor (BDNF) levels vary in various conditions including alcohol use disorder (AUD). We aimed to identify drivers of these variations.MethodsTwelve patients with AUD were assessed at hospitalisation for alcohol withdrawal and four months later. We looked for associations between the change in serum BDNF levels and (1) length of abstinence, (2) anxiety (Hamilton Anxiety Scale) and depression (Beck-Depression Inventory), (3) one functional BDNF genotype (rs6265) and (4) methylation levels of 12 CpG sites within the BDNF gene (located in exons I, IV and IX).ResultsWhile abstinence remained, serum BDNF level increased. This increase correlated with the variation of methylation levels of the BDNF gene, and more specifically of exon I. We found no significant effect of length of abstinence, rs6265, depression or anxiety on serum BDNF level.ConclusionsEpigenetic regulation of the BDNF gene may be involved in variations of BDNF blood level associated with alcohol abstinence.

Automated summary

This study aimed to identify factors that influence the changes in brain-derived neurotrophic factor (BDNF) levels during alcohol abstinence. The researchers examined the associations between the change in serum BDNF levels and length of abstinence, anxiety and depression scores, a functional BDNF genotype, and methylation levels of 12 CpG sites within the BDNF gene. The results showed that serum BDNF levels increased during abstinence and correlated with the variation in methylation levels of the BDNF gene, particularly exon I. There was no significant effect of abstinence length, genotype, depression, or anxiety on serum BDNF levels. Therefore, epigenetic regulation of the BDNF gene may play a role in the variations of BDNF levels during alcohol abstinence.