Das Mikrobiom des Darms: Dysbiose

Zusammenfassung

Das Mikrobiom des Darms wird gelegentlich auch als das „zweite menschliche Genom“ bezeichnet, da es eine hoch relevante Bedeutung in Gesundheit, aber auch Krankheit hat. Im Darm gibt es eine beeindruckend große Anzahl von Bakterien, die eine enge Beziehung zum Wirt pflegen. In bestimmten Situationen kann es zu einer Dysbiose kommen, was in der Konsequenz eine Schädigung des Wirtes nach sich ziehen kann. In den Bakterien werden zahlreiche Substanzen gebildet, die vom gesunden Körper nach der Aufnahme unkompliziert verstoffwechselt bzw. ausgeschieden werden können. Bei Patienten mit terminaler Nierenfunktionsstörung hingegen kommt es zum einen zu einer Veränderung des Darmmikrobioms und gleichzeitig zu einer Akkumulation von aus dem Darm aufgenommenen Substanzen, die durch das veränderte Mikrobiom produziert und nicht mehr eliminiert werden können. Dies führt zu einer Akkumulation von Urämietoxinen, die auch wesentlich zu dem exzessiven, v. a. kardiovaskulären Mortalitätsrisiko der Patienten beitragen. Eine Strategie zur Hilfe für den betroffenen Patienten mag die Wiederherstellung des Mikrobioms sein. In der vorliegenden Übersicht werden die Veränderungen des Mikrobioms und deren Auswirkungen vorgestellt. Auch Ideen für eine Beeinflussung des Mikrobioms werden diskutiert.

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