The Role of the BDNF Val66Met Polymorphism in Recovery of Aphasia After Stroke

Abstract

This study investigated the effect of the BDNF Val66Met polymorphism on clinical recovery of poststroke aphasia. In contrast to earlier studies describing a reducing effect of this polymorphism on motor function recovery after stroke, the present study does not support a reduction in language recovery for carriers compared to noncarriers with poststroke aphasia.

BDNF genotype and tDCS interaction in aphasia treatment

“…A baseline difference in language performance between carriers of typical or atypical BDNF gene was an unexpected finding as others have not revealed similar results. A study by de Boer et al [ 38 ] found neither baseline nor overall recovery differences in a group of 53 patients with stroke induced aphasia. However, there was one crucial difference between their research and the current study: Baseline examination of the patients in the de Boers et al study occurred within one-month post-stroke and aphasia treatment commenced immediately thereafter.…”

“…If BDNF genotype influences recovery in aphasia, it is possible that its effects are too subtle to be detected so soon after stroke. Specifically, had de Boers et al [ 38 ] followed their patients several years post stroke, it is possible that the effects of BDNF genotype may have been detected. In the current study, the average time post-stroke at enrollment was greater than 3.5 years.…”

Brain-Derived Neurotrophic Factor and Its Potential Therapeutic Role in Stroke Comorbidities

“…In previous studies using rat ischemia models, it was found that when BDNF synthesis was blocked, the beneficial effects on the recovery of skilled reaching were mostly negated [79], while intravenous administration of BDNF significantly enhanced the functional motor recovery of the treated rats, compared to the untreated controls [80,81]. Behavioral and physical therapies, such as aerobic/physical exercise, transcranial direct current stimulation (tDCS), and extremely lowfrequency electromagnetic field therapy (ELF-EMF), were all found to increase the blood and/or brain levels of BDNF [72,77,[82][83][84][85]. In addition, BDNF-mediated learning memory may also be partially involved in the poststroke rehabilitation of motor function and language relearning [86-88].…”

Aerobic Exercise as an Adjuvant to Aphasia Therapy: Theory, Preliminary Findings, and Future Directions

“…However, recent findings suggest that the BDNF Val66Met polymorphism may not negatively impact language recovery soon after a stroke. 49 With regard to individual factors, studies have also shown that those who perform lowest at baseline benefit the most from exercise. For example, Sibley and Beilock 50 demonstrated that individuals with the lowest baseline working memory ability showed the greatest improvements on a working memory task following a single bout of exercise.…”