Putaminal y‐Aminobutyric Acid Modulates Motor Response to Dopaminergic Therapy in Parkinson's Disease

Abstract

Background: Motor response to dopaminergic therapy is a characteristic of patients with Parkinson's disease (PD). Whether nondopaminergic neurotransmitters contribute to treatment response is uncertain.Objectives: The aim of this study is to determine whether putaminal y-aminobutyric acid (GABA) levels are associated with dopaminergic motor response. Methods: We assessed putaminal GABA levels in 19 PD patients and 13 healthy controls (HCs) utilizing ultra-high field proton magnetic resonance spectroscopy. Motor performance was evaluated using the Movement Disorder Society-Unified Parkinson's Disease Rating Scale, Part III, in the ON and OFF states. Statistical analysis comprised group comparisons, correlation analysis, and multiple linear regression. Results: In PD, GABA levels were significantly higher compared to HCs (1.50 AE 0.26 mM vs. 1.26 AE 0.31 mM, P = 0.022). Furthermore, GABA levels were independent predictors of absolute and relative dopaminergic treatment response. Conclusions: Our findings indicate that elevated putaminal GABA levels are associated with worse dopaminergic response in PD, emphasizing the essential role of nondopaminergic neurotransmitters in motor response.

Meta-analysis and Open-source Database for In Vivo Brain Magnetic Resonance Spectroscopy in Health and Disease

“…Studies that investigated clinical groups and included a healthy control group were included in the clinical population analysis. There were 180 publications [141,142,157,305,306,308,[310][311][312]317,321,322,328,160,[329][330][331][332][333]335,337,[339][340][341]161,342,345,[350][351][352][353][354][359][360][361]162,362,364,365,[368][369][370][371][372][373][374]163,377,378,…”

“…These age ranges allowed for the greatest number of studies to be included in each of the categories while leaving a gap (e.g., 46-49 years of age) to set groups apart. There were 8 [141][142][143][144][145][146][147], 19 [148,149,[158][159][160][161][162][163][164][165][166][150][151][152][153][154][155][156][157] [183,205,[360][361][362][363][364][365][366][367][368][369]207,[370][371][372][373][374][375][376][377][378]…”

Quantification of the neurochemical profile of the human putamen using STEAM MRS in a cohort of elderly subjects at 3 T and 7 T: Ruminations on the correction strategy for the tissue voxel composition

“…MRS spectra were acquired from the putamen of 15 healthy subjects (age 53 to 80 years, mean 67.7 ± 8.3 years, six females and nine males) in the framework of a case-control Parkinson's disease study [4]. Due to the limited range of φ GM in the MRS voxels of that study, five more age-matched subjects (three VOIs each) were measured.…”

“…Proton magnetic resonance spectroscopy (1H-MRS) enables the quantification of metabolite concentrations in vivo. It has proven to be a valuable tool for the assessment of several pathologies and disorders of the human brain, such as tumours [1], Alzheimer's disease [2,3] and Parkinson's disease [4,5], as well as for the study of healthy ageing [6,7]. Although the added value of 1H-MRS is greatly enhanced if the metabolite concentration is provided in absolute units (e.g.…”

“…The primary goal of this study is to quantify the neurochemical profile of the human putamen in vivo using pre-existing experimental spectra from healthy control subjects. The data were acquired in a case-control study on Parkinson's disease using an ultra-short TE, singlevoxel stimulated echo acquisition mode (STEAM) [23,24] sequence at 3 Tesla (T) and 7 T [4]. The putamen was chosen due to its central role in the pathophysiology of Parkinson's disease.…”