Recurrent dislocation of binocular crystal lenses in a patient with cystathionine beta-synthase deficiency.
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ABSTRACT: Background
Ectopia lentis is the common ocular manifestation of homocystinuria resulting from cystathionine beta-synthase (CBS) deficiency which has a high risk of thromboembolic complications.Case presentation
The present study reports the case of a teenager with recurrent lens dislocation and glaucoma. He was diagnosed with CBS deficiency according to a high level of serum homocysteine and compound heterozygous mutations at two different positions on the CBS gene. Antiglaucoma eyedrops and a mydriatic successfully controlled the intraocular pressure, while oral pyridoxine and betaine uptake lowered the serum homocysteine level effectively.Conclusions
Children with CBS deficiency may suffer from ectopia lentis, glaucoma and/or amblyopia. We firstly discovered a new mutation of CBS c. 697 T > G which had not been reported before. The patient was pyridoxine responsive and well controlled by medicine.
SUBMITTER: Hua N
PROVIDER: S-EPMC8120774 | biostudies-literature |
REPOSITORIES: biostudies-literature
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2017-12-07 | GSE91000 | GEO
Project description:Accumulation of the homocysteine (Hcy) precursor S-adenosylhomocysteine (AdoHcy) may cause cellular hypomethylation in the setting of hyperhomocysteinemia because of cystathionine β-synthase (CBS) deficiency, an inborn error of metabolism. To test this hypothesis, DNA and protein arginine methylation status were assessed in liver, brain, heart, and kidney obtained from a previously described mouse model of CBS deficiency. Metabolite levels in tissues and serum were determined by high-performance liquid chromatography or liquid chromatography-electrospray ionization-tandem mass spectrometry. Global DNA and protein arginine methylation status were evaluated as the contents of 5-methyldeoxycytidine in DNA and of methylarginines in proteins, respectively. In addition, histone arginine methylation was assessed by Western blotting. CBS-deficient mice exhibited increased (>6-fold) Hcy and AdoHcy levels in all tissues examined compared with control levels. In addition, global DNA methylation status was not affected, but global protein arginine methylation status was decreased (10-35%) in liver and brain. Moreover, asymmetric dimethylation of arginine 3 on histone H4 (H4R3me2a) content was markedly decreased in liver, and no differences were observed for the other histone arginine methylation marks examined. Our results show that CBS-deficient mice present severe accumulation of tissue Hcy and AdoHcy, protein arginine hypomethylation in liver and brain, and decreased H4R3me2a content in liver. Therefore, protein arginine hypomethylation arises as a potential player in the pathophysiology of CBS deficiency.
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