Kreatin Sentez ve Transport Bozuklukları
Özet
Serebral kreatin eksikliği sendromları; zihinsel yetersizlik, otizm, konuşma geriliği ve epilepsi gibi ciddi nörolojik belirtilerle seyreden tedavi edilebilir metabolik hastalıklardır. Bu sendromlar, kreatin sentezinde görevli GAMT ve AGAT enzim eksiklikleri veya kreatin taşıyıcısı olan SLC6A8 genindeki defektler nedeniyle ortaya çıkar. Erken teşhis, klinik belirtilerin görüldüğü vakalarda beyin gelişimi ve bilişsel fonksiyonların korunması açısından kritik öneme sahiptir. Tanıda beyin MRS ve biyokimyasal analizler kullanılırken, tedavi süreci takviyeler ve diyet düzenlemeleriyle multidisipliner bir yaklaşımla yürütülmektedir.
Cerebral creatine deficiency syndromes are treatable metabolic disorders characterized by serious neurological symptoms such as intellectual disability, autism, speech delay, and epilepsy. These syndromes arise due to deficiencies in the GAMT and AGAT enzymes responsible for creatine synthesis or defects in the SLC6A8 gene that functions as the creatine transporter. Early diagnosis is critical for protecting brain development and cognitive functions in cases where clinical symptoms appear. While brain MRS and biochemical analyses are used for diagnosis, the treatment process is managed through supplements and dietary adjustments tailored to the individual.
Referanslar
Lim YT, Mankad K, Kinali M, Tan AP. Neuroimaging Spectrum of Inherited Neurotransmitter Disorders. Neuropediatrics. 2020 Feb;51(1):6-21.
van Karnebeek C, Stockler-Ipsiroglu S. Congenital disorders of creatine synthesis and transport.In: Up To Date Genetic diseases in children [online]. Available at:www.uptodate.com/contents/congenital-disorders-of-creatine-synthesis-and-transport. Accessed May, 2021.
Mercimek-Mahmutoglu S, Salomons GS. Creatine deficiency syndromes. In: GeneReview Creatine Deficiency Syndromes [Internet], Pagron RA, Adam MP, Ardinger HH, et al (Eds), University of Washington, Seattle 2015.
Nyhan WL, Hoffmann GF. Disorders of Creatine Synthesis or Transport. Nyhan WL, Hoffmann GF Editors. Atlas of Inherited Metabolic Diseases Fourth Ed. Taylor & Francis Group. Boca Raton 2020. p 787-792
Stockler-Ipsiroglu S, Mercimek-Mahmutoglu S, Salomons GS. Creatine deficiency syndromes. Saudubray J M, Baumgartner MR, Walter J (Eds). Inborn Metabolic Diseases: Diagnosis and Treatment, 6th ed., Springer, Berlin 2016.
Stockler S, Isbrandt D, Hanefeld F, Schmidt B, von Figura K. Guanidinoacetate methyltransferase deficiency: the first inborn error of creatine metabolism in man. Am J Hum Genet. 1996 May;58(5):914-22.
Bianchi MC, Tosetti M, Fornai F, et al. Reversible brain creatine deficiency in two sisters with normal blood creatine level. Ann Neurol. 2000 Apr;47(4):511-3.
Salomons GS, van Dooren SJ, Verhoeven NM et al. X-linked creatine-transporter gene (SLC6A8) defect: a new creatine-deficiency syndrome. Am J Hum Genet. 2001 Jun;68(6):1497-500.
Lion-François L, Cheillan D, Pitelet G et al. High frequency of creatine deficiency syndromes in patients with unexplained mental retardation. Neurology. 2006 Nov 14;67(9):1713-4.
Hanna-El-Daher L, Braissant O. Creatine synthesis and exchanges between brain cells: What can be learned from human creatine deficiencies and various experimental models? Amino Acids. 2016 Aug;48(8):1877-95.
Dunbar M, Jaggumantri S, Sargent M, Stockler-Ipsiroglu S, van Karnebeek CD. Treatment of X-linked creatine transporter (SLC6A8) deficiency: systematic review of the literature and three new cases. Mol Genet Metab. 2014 Aug;112(4):259-74
van de Kamp JM, Betsalel OT, Mercimek-Mahmutoglu S, Abdulhoul L et al. Phenotype and genotype in 101 males with X-linked creatine transporter deficiency. J Med Genet. 2013a;50:463–72.
Khaikin Y, Sidky S, Abdenur J et al. Treatment outcome of twenty-two patients with guanidinoacetate methyltransferase deficiency: An international retrospective cohort study. Eur J Paediatr Neurol. 2018 May;22(3):369-379.
Stockler-Ipsiroglu S, van Karnebeek C, Longo N et al. Guanidinoacetate methyltransferase (GAMT) deficiency: outcomes in 48 individuals and recommendations for diagnosis, treatment and monitoring. Mol Genet Metab. 2014;111:16–25.
Mercimek-Mahmutoglu S, Ndika J, Kanhai W et al. Thirteen new patients with guanidinoacetate methyltransferase deficiency and functional characterization of nineteen novel missense variants in the GAMT gene. Hum Mutat. 2014a;35:462–9.
Battini R, Leuzzi V, Carducci C, et al. Creatine depletion in a new case with AGAT deficiency: clinical and genetic study in a large pedigree. Mol Genet Metab 2002; 77:326.
Betsalel OT, Pop A, Rosenberg EH et al.Detection of vari- ants in SLC6A8 and functional analysis of unclassified missense variants. Mol Genet Metab 2012; 105:596–601
van de Kamp JM, Errami A, Howidi M et al. Genotype- phenotype correlation of contiguous gene deletions of SLC6A8, BCAP31 and ABCD1. Clin Genet 2015; 87:141–147
Farr CV, El-Kasaby A, Freissmuth M, Sucic S. The Creatine Transporter Unfolded: A Knotty Premise in the Cerebral Creatine Deficiency Syndrome. Front Synaptic Neurosci. 2020 Oct 23;12:588954.
Mercimek-Mahmutoglu S, Stoeckler-Ipsiroglu S, Adami A et al. GAMT deficiency: features, treatment, and outcome in an inborn error of creatine synthesis. Neurology. 2006;67:480–4.
Mercimek-Mahmutoglu S, Ndika J, Kanhai W et al. Thirteen new patients with guanidinoacetate methyltransferase deficiency and functional characterization of nineteen novel missense variants in the GAMT gene. Hum Mutat. 2014 Apr;35(4):462-9.
van de Kamp JM, Jakobs C, Gibson KM, Salomons GS. New insights into creatine transporter deficiency: the importance of recycling creatine in the brain. J Inherit Metab Dis. 2013b;36:155–6.
Yıldız Y, Göçmen R, Yaramış A, Coşkun T, Haliloğlu G. Creatine Transporter Deficiency Presenting as Autism Spectrum Disorder. Pediatrics. 2020 Nov;146(5):e20193460.
Anselm IA, Coulter DL, Darras BT. Cardiac manifestations in a child with a novel mutation in creatine transporter gene SLC6A8. Neurology. 2008;70:1642–4.
Puusepp H, Kall K, Salomons GS et al. The screening of SLC6A8 deficiency among Estonian families with X-linked mental retardation. J Inherit Metab Dis. 2010;33 Suppl 3:S5–11.
Reichold M, Klootwijk ED, Reinders J, et al. Glycine Amidinotransferase (GATM), Renal Fanconi Syndrome, and Kidney Failure. J Am Soc Nephrol. 2018;29(7):1849-1858.
Joncquel-Chevalier Curt M, Voicu PM, Fontaine M et al. Creatine biosynthesis and transport in health and disease. Biochimie. 2015 Dec;119:146-65.
Verhoeven NM, Schor DS, Roos B et al. Diagnostic enzyme assay that uses stable-isotope-labeled substrates to detect L-arginine:glycine amidinotransferase deficiency. Clin Chem. 2003 May;49(5):803-5.
Item CB, Stockler-Ipsiroglu S, Stromberger C et al. Arginine:glycine amidinotransferase deficiency: the third inborn error of creatine metabolism in humans. Am J Hum Genet. 2001 Nov;69(5):1127-33.
Pasquali M, Schwarz E, Jensen M et al. Feasibility of newborn screening for guanidinoacetate methyltransferase (GAMT) deficiency. J Inherit Metab Dis. 2014 Mar;37(2):231-6.
Sinclair GB, van Karnebeek CDM, Ester M et al. A three-tier algorithm for guanidinoacetate methyltransferase (GAMT) deficiency newborn screening. Mol Genet Metab. 2016 Jul;118(3):173
Mercimek-Mahmutoglu S, Dunbar M, Friesen A, et al. Evaluation of two year treatment outcome and limited impact of arginine restriction in a patient with GAMT deficiency. Mol Genet Metabol 2012;105:155e8.
Mercimek-Mahmutoglu S, Salomons GS, Chan A. Case study for the evaluation of current treatment recommendations of guanidinoacetate methyltransferase deficiency: ineffectiveness of sodium benzoate. Pediatr Neurol 2014;51:133e7.
Battini R, Alessandrì MG, Casalini C, et al. Fifteen-year follow-up of Italian families affected by arginine glycine amidinotransferase deficiency. Orphanet J Rare Dis 2017; 12:21.
Ndika JD, Johnston K, Barkovich JA, et al. Developmental progress and creatine restoration upon long-term creatine supplementation of a patient with arginine:glycine amidinotransferase deficiency. Mol Genet Metab 2012; 106:48.
Bianchi MC, Tosetti M, Battini R, et al. Treatment monitoring of brain creatine deficiency syndromes: a 1H- and 31P-MR spectroscopy study. AJNR Am J Neuroradiol 2007; 28:548.
Mercimek-Mahmutoglu S, Connolly MB, Poskitt KJ, et al. Treatment of intractable epilepsy in a female with SLC6A8 deficiency. Mol Genet Metab 2010; 101:409.
Valayannopoulos V, Boddaert N, Chabli A, et al. Treatment by oral creatine, L-arginine and L-glycine in six severely affected patients with creatine transporter defect. J Inherit Metab Dis 2012; 35:151.
van de Kamp JM, Pouwels PJ, Aarsen FK, et al. Long-term follow-up and treatment in nine boys with X-linked creatine transporter defect. J Inherit Metab Dis 2012; 35:141.