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DIE DARM-GEHIRN-ACHSE: AKTUELLE ERKENNTNISSE

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Abstract

Immer mehr wissenschaftliche Studien deuten auf einen Zusammenhang zwischen Magen- Darm-Trakt (GI) und Gehirnfunktion hin - und damit auf einen Zusammenhang mit neurologischen und psychiatrischen Erkrankungen. Darmerkrankungen werden als "Risikofaktor" für die Entwicklung neurologischer Erkrankungen wie Parkinson oder Alzheimer angesehen. Darüber hinaus wird vermutet, dass die "Darm-Hirn-Achse" an einer Reihe von psychiatrischen oder neuroimmunologischen Störungen im Kindes- und Erwachsenenalter beteiligt ist, darunter Autismus, Aufmerksamkeitsdefizit-Hyperaktivitäts- Syndrom (ADHS), Schizophrenie, Depressionen und Multiple Sklerose. Der Darm ist ein komplexes System, das eine grundlegende Rolle bei der Aufnahme und Verteilung von Nährstoffen spielt, die für die verschiedenen Organe eines Organismus notwendig sind, wie beispielsweise Glukose für das Gehirn. Fein reguliert durch das Nervensystem, beherbergt der Verdauungstrakt einen Vertreter, der eine entscheidende Rolle spielt: die Darmflora – auch bekannt als "Mikrobiom" – das so viel wiegt wie das Gehirn selbst! Da der Magen-Darm-Trakt dem Risiko einer Invasion durch Krankheitserreger ausgesetzt ist, spielt ein vierter Protagonist eine Schlüsselrolle: das Immunsystem. Letzteres überwacht den Magen-Darm-Trakt und spielt eine wichtige Rolle bei der Vermittlung von Interaktionen zwischen Darm und Gehirn, zum Guten wie zum Schlechten... Ob Darm oder Gehirn, beide Organe sind vom Rest des Körpers durch Barrieren isoliert, deren einwandfreie Funktion lebenswichtig ist und die den Körper und das Gehirn vor potenziell tödlichen Infektionen schützen. Und doch... Anatomische Wege verbinden sie. Diese Wege tragen auf unterschiedliche Weise zum Dialog zwischen diesen verschiedenen Protagonisten bei, aber auch zu ihrer Verletzlichkeit. So ist der Mensch letztlich ein komplexes Amalgam aus menschlichen Zellen und Bakterienzellen, die bei der Kontrolle der menschlichen Gesundheit eng zusammenarbeiten. Nicht nur, dass die Darmflora in der Lage ist, bestimmte Nährstoffe zu verdauen, die durch den Magen-Darm-Trakt selbst nicht abgebaut werden können. Eine wachsende Zahl wissenschaftlicher Studien legt auch einen Zusammenhang zwischen der Magen-Darm-Funktion (GI) und der Gehirnfunktion nahe - und damit einen Zusammenhang mit bestimmten neurologischen und psychiatrischen Erkrankungen. So wird vermutet, dass die Darm- Hirn-Achse an einer Reihe von psychiatrischen oder neuroimmunologischen Erkrankungen bei Kindern und Erwachsenen beteiligt ist. So entstand das Konzept der "Darm-Hirn-Achse", nach dem es einen ständigen Dialog zwischen Darm und Gehirn gibt. Lebende Tiere sollten daher nicht mehr nur als autarke Inseln betrachtet werden, sondern als eine komplexe Landschaft, in der Mikroben und Wirtszellen mehr oder weniger harmonisch zusammenleben. Dies ist die fabelhafte Geschichte der Darm-Mikrobiota–Hirn– Achse, einem echten Ökosystem, in dem ein fruchtbarer Austausch das neurologische und psychische Gleichgewicht des Menschen beeinflussen könnte und dessen Funktionsgeheimnisse wir diskutieren werden…
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