Combining inhibitory and facilitatory repetitive transcranial magnetic stimulation (rTMS) treatment improves motor function by modulating GABA in acute ischemic stroke patients.
Qing-Mei Chen, Fei-Rong Yao, Hai-Wei Sun, Zhi-Guo Chen, Jun Ke, Juan Liao, Xiu-Ying Cai, Li-Qiang Yu, Zhen-Yan Wu, Zhi Wang, Xi Pan, Hao-Yu Liu, Li Li, Quan-Quan Zhang, Wei-Hua Ling, Qi Fang
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引用次数: 3
Abstract
Background: The combination of inhibitory and facilitatory repetitive transcranial magnetic stimulation (rTMS) can improve motor function of stroke patients with undefined mechanism. It has been demonstrated that rTMS exhibits a neuro-modulatory effect by regulating the major inhibitory neurotransmitter γ-aminobutyric acid (GABA) in other diseases.
Objectives: To evaluate the effect of combined inhibitory and facilitatory rTMS on GABA in the primary motor cortex (M1) for treating motor dysfunction after acute ischemic stroke.
Methods: 44 ischemic stroke patients with motor dysfunction were randomly divided into two groups. The treatment group was stimulated with 10 Hz rTMS at the ipsilesional M1 and 1 Hz rTMS at the contralesional M1. The sham group received bilateral sham stimulation at the motor cortices. The GABA level in the bilateral M1 was measured by proton magnetic resonance spectroscopy (1H-MRS) at 24 hours before and after rTMS stimulation. Motor function was measured using the Fugl-Meyer Assessment (FMA). The clinical assessments were performed before and after rTMS and after 3 months.
Results: The treatment group exhibited a greater improvement in motor function 24 hours after rTMS compared to the sham group. The increased improvement in motor function lasted for at least 3 months after treatment. Following 4 weeks of rTMS, the GABA level in the ipsilesional M1 of the treatment group was significantly decreased compared to the sham group. Furthermore, the change of FMA score for motor function was negatively correlated to the change of the GABA:Cr ratio. Finally, the effect of rTMS on motor function outcome was partially mediated by GABA level change in response to the treatment (27.7%).
Conclusions: Combining inhibitory and facilitatory rTMS can decrease the GABA level in M1, which is correlated to the improvement of motor function. Thus, the GABA level in M1 may be a potential biomarker for treatment strategy decisions regarding rTMS neuromodulatory interventions.
期刊介绍:
This interdisciplinary journal publishes papers relating to the plasticity and response of the nervous system to accidental or experimental injuries and their interventions, transplantation, neurodegenerative disorders and experimental strategies to improve regeneration or functional recovery and rehabilitation. Experimental and clinical research papers adopting fresh conceptual approaches are encouraged. The overriding criteria for publication are novelty, significant experimental or clinical relevance and interest to a multidisciplinary audience. Experiments on un-anesthetized animals should conform with the standards for the use of laboratory animals as established by the Institute of Laboratory Animal Resources, US National Academy of Sciences. Experiments in which paralytic agents are used must be justified. Patient identity should be concealed. All manuscripts are sent out for blind peer review to editorial board members or outside reviewers. Restorative Neurology and Neuroscience is a member of Neuroscience Peer Review Consortium.