Article

Curcumin und Multiple Sklerose

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Abstract

Multiple Sklerose (MS) ist eine körpereigene Immunreaktion, die Zellen des zentralen Nervensystems angreift und in zunehmenden Maße schädigt. Die Schäden entstehen wahrscheinlich durch reaktive Sauerstoffspezies und Stickstoffmonoxid. Das Letzere wird von Stickstoffmonoxid-Synthasen (NO) produziert. Im Tiermodell für MS, der experimentellen autoimmunen Encephalomyelitis (EAE), wurde eine erhöhte Expression von Arginase I festgestellt. Hemmung der Arginase verzögert das Auftreten der EAE-Symptome. Da Arginasen und NO um dasselbe Substrat Arginin konkurrieren, könnte die Verdrängung von NO durch Arginase zu einer verringerten Stickstoffmonoxid-Konzentration führen und dann über negative Rückkopplung zu einer verstärkten Produktion von NO. Es ist bekannt, dass die Prävalenz von MS in Gesellschaften, in denen täglich Curcumin verzehrt wird, niedriger ist als in der nördlichen Hemisphäre. Curcuma-Bestandteile hemmen Arginasen in vitro und wechselwirken direkt mit dem Enzym. Daraus könnte ein Ansatz in der MS-Behandlung abgeleitet werden. Curcumin and Multiple Sclerosis In Multiple Sclerosis (MS), the inflammation caused by the patient's own immune system against the central nervous tissue leads to progressive loss of neurological functions. Reactive oxygenated species and nitric oxid, the latter produced by nitric oxid-Synthases (NO) destroy axons and myelin sheets. In experimental autoimmune encephalomyelitis (EAE), an animal model for MS, arginase I expression is upregulated and an inhibition of arginase helps to delay the onset of EAE-symptoms. Since arginases compete with NO for the substrate arginine, a complex network regulates NO activity. The prevalence of MS in societies, where curcumin is part of the daily diet, is lower than in the northern hemisphere. A specific inhibition of arginases by curcuma extract in vitro and evidence for a direct association of compounds therein with arginases suggests a perspective for the treatment of MS.

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