Hiperhomosisteinemi ve karaciğer yağlanması: Eski ikilemin “yumurta mı tavuk mu?” karaciğere uygulanması
İletişim:Engin ALTINTAŞ Mersin Üniversitesi Tıp Fakültesi Zeytinlibahçe Cad. Eskiotogar Yanı İç Hastalıkları A.D. 33079 Mersin, Türkiye • Tel: + 90 324 337 43 00 Fax: + 90 324 336 71 17 • E-mail: enginaltintas@mersin.edu.tr
Hyperhomocysteinemia and liver steatosis: Modification of “the chicken or the egg?” dilemma to the liver
Homocysteine (Hcy) is a sulfur-containing amino acid that is formed as an intermediary in methionine metabolism (1). Extensive evidence shows that elevated plasma Hcy concentration, a reflection of impaired cellular metabolism, can be considered as an independent risk factor for atherothrombotic vascular disease (2). This condition has been observed in 20% to 30% of patients with premature arteriosclerosis and in 21% of the general population above a certain age (3,4). Three enzymes utilize Hcy as a substrate: methionine synthase (MS) and betaine-homocysteine methyltransferase (BHMT), which convert Hcy back to methionine, and cystathionine β-synthase (CBS), the first enzyme in the transsulfuration pathway (1) (Figure 1)
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