ObjectiveGlucocerebrosidase gene (GBA) variants that cause Gaucher disease are associated with Parkinson disease (PD) and dementia with Lewy bodies (DLB). To investigate the role of GBA variants in multiple system atrophy (MSA), we analyzed GBA variants in a large case–control series.MethodsWe sequenced coding regions and flanking splice sites of GBA in 969 MSA patients (574 Japanese, 223 European, and 172 North American) and 1509 control subjects (900 Japanese, 315 European, and 294 North American). We focused solely on Gaucher-disease-causing GBA variants.ResultsIn the Japanese series, we found nine carriers among the MSA patients (1.65%) and eight carriers among the control subjects (0.89%). In the European series, we found three carriers among the MSA patients (1.35%) and two carriers among the control subjects (0.63%). In the North American series, we found five carriers among the MSA patients (2.91%) and one carrier among the control subjects (0.34%). Subjecting each series to a Mantel–Haenszel analysis yielded a pooled odds ratio (OR) of 2.44 (95% confidence interval [CI], 1.14–5.21) and a P-value of 0.029 without evidence of significant heterogeneity. Logistic regression analysis yielded similar results, with an adjusted OR of 2.43 (95% CI 1.15–5.37) and a P-value of 0.022. Subtype analysis showed that Gaucher-disease-causing GBA variants are significantly associated with MSA cerebellar subtype (MSA-C) patients (P = 7.3 × 10−3).InterpretationThe findings indicate that, as in PD and DLB, Gaucher-disease-causing GBA variants are associated with MSA.

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IMPORTANCE Multiple system atrophy (MSA) is an intractable neurodegenerative disease characterized by autonomic failure in addition to various combinations of parkinsonism, cerebellar ataxia, and pyramidal dysfunction. It has recently been reported that functionally impaired variants of COQ2, which encodes an essential enzyme in the biosynthetic pathway of coenzyme Q10 (CoQ10), are associated with MSA. However, little is known about the role of CoQ10 in the pathogenesis of MSA. OBJECTIVE To compare the levels of plasma CoQ10 in patients with MSA with those in age-, sex-, and COQ2 genotype-matched controls. DESIGN, SETTING, AND PARTICIPANTS We enrolled 44 Japanese patients with MSA and 39 Japanese controls from September 1, 2012, to December 31, 2015. Patients with MSA were diagnosed on the basis of the second consensus criteria by at least 2 neurologists. Plasma CoQ10 levels were measured by high-performance liquid chromatography with electrochemical detection. Sanger sequencing of COQ2 was performed to determine the COQ2 genotypes. Multiple logistic regression analysis was performed to determine the association between MSA and the plasma CoQ10 level. MAIN OUTCOMES AND MEASURES Plasma CoQ10 levels in patients with MSA were compared with those in controls after adjusting for age, sex, and COQ2 genotype. RESULTS Among 44 patients with MSA (mean [SD] age, 63.7 [8.3] years) and 39 controls (mean [SD] age, 60.3 [13.0] years), the mean (SD) plasma level of CoQ10 in patients with MSA was lower than that in controls (0.51 [0.22] vs 0.72 [0.42] μg/mL; P = .01) (difference between medians: −0.14; 95% CI,-0.25 to-0.03). The mean (SD) plasma levels of CoQ10 in patients with the cerebellar variant of MSA and those with the parkinsonian variant of MSA were 0.58 (0.19) and 0.49 (0.26) μg/mL, respectively. After adjusting for age, sex, and COQ2 genotype, the levels of plasma CoQ10 were significantly associated with MSA (95% CI, 0.10; range, 0.02 to 0.66) (P = .02). CONCLUSIONS AND RELEVANCE Our data showed decreased levels of plasma CoQ10 in patients with MSA regardless of the COQ2 genotype, supporting a hypothesis that supplementation with CoQ10 is beneficial for patients with MSA.

Human insulin-like growth factor-I (IGF-I) was studied by two-dimensional 1H-NMR spectroscopy. Resonance assignments were obtained for all the backbone protons and almost all of the sidechain protons of the total 70 amino acid residues, using sequence-specific assignment procedures. The secondary structure elements of human IGF-I were identified by investigation of the sequential and medium range NOEs as a preliminary step in determining the three-dimensional structure of this protein by means of distance geometry calculations. The typical NOEs of d alpha beta(i,i + 3) and d alpha N(i,i + 3), as well as the successive strong NOEs of dNN connectivities and slowly exchanging amide protons confirmed the presence of three helical segments corresponding to the sequence regions, Ala8-Cys18, Gly42-Cys48, and Leu54-Cys61, and the existence of a beta-turn in the Gly19-Gly22 region. Our results definitely indicate that the secondary structure of human IGF-I in solution is consistent with that of insulin in the crystalline state.

We report a 3-year follow-up of high-dose ubiquinol supplementation in a case of familial multiple system atrophy (MSA) with compound heterozygous nonsense (R387X) and missense (V393A) mutations in COQ2. A high-dose ubiquinol supplementation substantially increased total coenzyme Q10 levels in cerebrospinal fluid as well as in plasma. The patient was at the advanced stage of MSA, and the various scores of clinical rating scales remained stable without changes during the 3 years. The cerebral metabolic ratio of oxygen measured by 15O2 PET, however, increased by approximately 30% after administration of ubiquinol, suggesting that ubiquinol can improve mitochondrial oxidative metabolism in the brain. It also suggests the therapeutic potential of ubiquinol for patients with MSA with COQ2 mutations. Further clinical trials of administration of high-dose ubiquinol to MSA patients are warranted.