Brain-derived neurotrophic factor (Val66Met) polymorphism does not influence recovery from a post-traumatic vegetative state: a blinded retrospective multi-centric study.
Brain-derived neurotrophic factor (BDNF) is a neurotrophin that influences neuronal plasticity throughout life. Emergence from a vegetative state (VS) after a traumatic brain injury (TBI) implies that the brain undergoes plastic changes. A common polymorphism in the BDNF gene--BDNF Val66Met (referred to herein as BDNF(Met))--impairs cognitive function in healthy subjects. The aim of this study was to determine whether the BDNF(Met) polymorphism plays a role in the recovery of consciousness and cognitive functions in patients in a VS after a TBI. Fifty-three patients in a VS 1 month after a TBI were included in the study and genotyped for the BDNF(Met) polymorphism. Scores of levels of cognitive functioning (LCF) at 1, 3, 6, and 12 months post-TBI were retrospectively compared in patients without (Val group), and with (Met group), the BDNF(Met) polymorphism. The BDNF(Met) polymorphism was detected in 20 out of the 53 patients. The mean LCF scores in the Val and Met groups were 1.6±0.5 and 1.4±0.5 at 1 month, 2.3±0.7 and 2.5±1.2 at 3 months, 3.3±1.7 and 3.5±1.7 at 6 months, and 4±1.9 and 3.9±1.8 at 12 months, respectively (p>0.05). The percentages of patients in the Val and Met groups who emerged from the VS were 36.4% and 30% at 3 months, 66.3% and 70% at 6 months, and 70% and 87.5% at 12 months (p>0.05), respectively. These findings provide evidence that the BDNF(Met) polymorphism is not involved in cognitive improvement in patients with a VS following TBI. Future studies should focus on the role of other BDNF polymorphisms in the recovery from a VS.
Unit for Severe Acquired Brain Injuries, Fondazione Istituto "San Raffaele-G. Giglio " Cefalù, Italy. sergiobagnato@gmail.com
Sergio
S
Bagnato
Luigi
L
Minafra
Valentina
V
Bravatà
Cristina
C
Boccagni
Antonino
A
Sant'angelo
Alberto
A
Castiglione
Maria
M
Andriolo
Lucia Francesca
LF
Lucca
Antonio
A
De Tanti
Caterina
C
Pistarini
Rita
R
Formisano
Giuliano
G
Dolce
Cecilia
C
Gelfi
Giuseppe
G
Galardi
D000293:Adolescent; D000328:Adult; D001930:Brain Injuries / Q000150:complications / Q000235:genetics; D019208:Brain-Derived Neurotrophic Factor / Q000235:genetics*; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D018458:Persistent Vegetative State / Q000209:etiology / Q000235:genetics*; D012150:Polymorphism, Restriction Fragment Length; D020641:Polymorphism, Single Nucleotide; D020127:Recovery of Function / Q000235:genetics*; D012189:Retrospective Studies; D055815:Young Adult
D019208:Brain-Derived Neurotrophic Factor