RT期刊文章SR电子T1减少大脑胆碱高胱氨酸尿由于remethylation缺陷摩根富林明神经病学神经学乔FD Lippincott Williams &威尔金斯SP 44 OP 49做wnl.0000316391.首页40236 10.1212/01.。71 c3 VO是1 A1 f - g。r A1 y面包师A1。Khiat A1 j - c。Decarie A1 j . Orquin A1 m - s。罗伊A1。Lortie A1 F。拉莫斯A1 n . m . Verhoeven A1大肠Struys A1 h·j·布鲁姆A1 c .手跟前A1 e . Levy A1 g·a·米切尔A1 m·兰伯特年2008 UL //www.ez-admanager.com/content/71/1首页/44.abstract AB目的:调查是否二次转甲基作用通路的障碍是神经机制参与高胱氨酸尿由于remethylation缺陷。方法:12神经疾病患者由于remethylation缺陷被大脑核磁共振光谱成像检查(1 h MRSI)。大脑N-acetylaspartate choline-containing化合物(Cho),肌酸(Cr)以控制量化和比较。代谢物的remethylation周期和肌酸生物合成途径测定血浆和尿液。 Results: MRSI revealed isolated Cho deficiency in all regions examined (mean concentration units ± SD, patients vs controls): frontal white matter (0.051 ± 0.010 vs 0.064 ± 0.010; p = 0.001), lenticular nucleus (0.056 ± 0.011 vs 0.069 ± 0.009; p < 0.001), and thalamus (0.063 ± 0.010 vs 0.071 ± 0.007; p = 0.006). In contrast to controls, the Cho/Cr ratio decreased with age in patients in the three brain regions examined. Low creatine urinary excretion (p < 0.005), normal urine and plasma guanidinoacetate, and a paradoxical increase in plasma S-adenosylmethionine (p < 0.005) concentrations were observed. Conclusion: Patients with homocystinuria due to remethylation defects have an isolated brain choline deficiency, probably secondary to depletion of labile methyl groups produced by the transmethylation pathway. Although biochemical studies suggest mild peripheral creatine deficiency, brain creatine is in the reference range, indicating a possible compartmentation phenomenon. Paradoxical increase of S-adenosylmethionine suggests that secondary inhibition of methylases contributes to the transmethylation defect in these conditions. CblC=combined homocystinuria-methylmalonic aciduria; CblG=methionine synthase deficiency; CBS=cystathionine β-synthase; Cho=water-soluble choline-containing compounds; Cr=creatine; DQ=developmental quotient; Met=plasma methionine; MR=magnetic resonance; MSRI=magnetic resonance spectroscopic imaging; MTHFR=methylene tetrahydrofolate reductase; NA=not available; NAA=N-acetylaspartate; NN=neonatal; NS=not significant; OA=optic atrophy; OMA=oculomotor apraxia; OMIM=Online Mendelian Inheritance in Man; PM=pigmentary maculopathy; Pt=patient; RD=remethylation defect; RP=retinitis pigmentosa; tHcy=plasma total homocysteine; THF=tetrahydrofolate.