Hunter syndrome: Long-term idursulfase treatment does not protect patients against DNA oxidation and cytogenetic damage

Mutat Res Genet Toxicol Environ Mutagen. 2018 Nov:835:21-24. doi: 10.1016/j.mrgentox.2018.08.013. Epub 2018 Aug 31.

Abstract

Mucopolysaccharidosis type II (MPS II or Hunter syndrome) is an inborn error of metabolism characterized by the accumulation of glycosaminoglycans (GAG) in lysosomes. Enzyme replacement therapy (ERT) can reduce GAG storage, ameliorate symptoms, and slow disease progression. Oxidative damages may contribute to the MPS II pathophysiology, and treatment with ERT might reduce the effects of oxidative stress. We evaluated levels of DNA damage (including oxidative damage) and chromosome damage in leukocytes of long-term-treated MPS II patients, by applying the buccal micronucleus cytome assay. We observed that, despite long-term ERT, MPS II patients had higher levels of DNA damage and higher frequencies of micronuclei and nuclear buds than did control. These genetic damages are presumably due to oxidation: we also observed increased levels of oxidized guanine species in MPS II patients. Therapy adjuvant to ERT should be considered, in order to decrease oxidative damage and cytogenetic alterations.

Keywords: Comet assay; Enzyme replacement therapy; Genotoxicity; Micronucleus; Mucopolysaccharidosis type II.

MeSH terms

  • Adolescent
  • Adult
  • Case-Control Studies
  • Child
  • Chromosome Aberrations*
  • DNA Damage*
  • Enzyme Replacement Therapy*
  • Glycoproteins / administration & dosage*
  • Glycoproteins / deficiency
  • Humans
  • Leukocytes / drug effects
  • Leukocytes / enzymology
  • Leukocytes / pathology*
  • Male
  • Mucopolysaccharidosis II / drug therapy
  • Mucopolysaccharidosis II / enzymology
  • Mucopolysaccharidosis II / genetics*
  • Mucopolysaccharidosis II / pathology
  • Oxidation-Reduction
  • Oxidative Stress
  • Treatment Outcome
  • Young Adult

Substances

  • Glycoproteins
  • IDS protein, human