İkinci beyin: Bağırsak

Öz

Bağırsak mikrobiyotası konakçılara paralel olarak gelişen ve konakçının fizyolojik ortamına bağlı karmaşık bir ekosistemi temsil etmektedir. Enterik sinir sisteminin 100 milyondan fazla nöron içermesi ve merkezi sinir sisteminden bağımsız işlev  görebilmesi onun ikinci beyin olarak adlandırılmasına da neden olmuştur. Bağırsak mikrobiyotası beyin ve bağırsak arasında bir ilişki oluşturarak insan sağlığı üzerinde önemli bir rol oynar. Hastalıklarla bağırsak mikrobiyotası arasındaki ilişki incelendiğinde bazı hastalıklarda özel bir mikrobiyota olduğu ortaya konmuştur. Bu mikrobiyota sağlıklı bir insanın mikrobiyotasından farklıdır. Obezite, diyabet gibi metabolik hastalıklar ve Parkinson, Alzheimer gibi nörodejeneratif bozukluklarla bağırsak mikrobiyotası arasında bağlantı olduğuna ilişkin güçlü kanıtlar sunulmuştur. Yapılan araştırmalar gastrointestinal sistemde yaşayan faydalı ve zararlı mikroorganizmaların immün sistemi, nöral yolakları ve merkezi sinir sistemini uyardığını ortaya koymaktadır. Bu mikroorganizmalar beyin ve bağırsak için önemli olan gama amino bütirik asit, dopamin ve serotonin gibi nörotransmitter maddeleri üretmektedir. Son yıllarda bağırsak mikrobiyotasına olan ilgi ve bu

doğrultuda yapılan çalışmalar bu bakterilerin çevresel faktörlerden nasıl etkilendiğini ve sinir sistemi üzerinde nasıl etkiler oluşturabildiğini göstermiştir. Çevresel etkenler ve beslenmenin bağırsak mikrobiyotası üzerindeki etkileri de son yıllarda açığa çıkmaya başlamıştır. Bu makalede bağırsak mikrobiyotasının beyin, davranış ve nöropsikiyatrik bozukluklar üzerine etkisi incelenmiştir.

Anahtar Kelimeler

• Alzheimer
• Bağırsak
• Beyin
• Mikrobiota
• Parkinson

Second brain: Gut

Öz

Intestinal microbiota represents a complex ecosystem that develops in parallel with the hosts and depends on the physiological environment of the host. The enteric nervous system containing more than 100 million neurons and its ability to function independently from the central nervous system also caused it to be called the second brain. The gut microbiota plays an important role in human health by creating a relationship between the brain and the gut. When the relationship between diseases and intestinal microbiota is examined, it is revealed that there is a special microbiota in some diseases. This microbiota is different from the microbiota of a healthy person. Strong evidence is provided that there is a link between metabolic diseases such as obesity, diabetes, and neurodegenerative disorders such as Parkinson and Alzheimer's, and intestinal microbiota. Research shows that beneficial and harmful microorganisms living in the gastrointestinal tract stimulate the immune system, neural pathways and central nervous system. These microorganisms produce neurotransmitter substances such as gamma amino butyric acid, dopamine and serotonin, which are important for the brain and intestine. In this article, the effects of intestinal microbiota on brain, behavior and neuropsychiatric disorders were investigated.

Anahtar Kelimeler

• alzheimer
• Brain
• Gut
• Microbiota
• Parkinson

Kaynakça

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