Immune System and Intestinal Mıcrobiota

Yıl 2017, - Mikrobiyota, 7 - 16, 15.11.2017

Şefik Şanal Alkan

Öz

Recent developments in the fi eld of metagenomics (study of the total DNA that can be extracted from an environment) have not only changed our understanding of entire living world but also our view on our bodie’s cellular composition and the role of the immune system in health and disease. We now know that our life depend on mutualistic partnerships (symbiosis) with the microbial communities that colonize in our bodies (called microbiota- the collective microbial community inhabiting a specifi c environment). As a host, we learn to recognize, restrain our mikcrobiota which we encounter before and after birth. Microbiome (which is the collective genomic content of a microbiota such as bacteria, fungi, and other single-celled microorganisms) infl uences our functions and behaviors. The composition and function of microbiomes are critical for animals and plants- thus, each considered as single ecological unit now called holobiont. The holobiont (the host and the microbiota) use tools shaped by millions of years of co-evolution to maintain a constant dialog and a mutualistic relationship. Under normal conditions, the commensal microbiota protects against colonization by pathogens. However, as with any relationship, things can go wrong. Small imbalances introduced by the host (the immune system), or ever mutating microbes can disturb the dynamic equilibrium between host and commensals. In such circumstances (called dysbiosis), microbiota can exert pathological effects that lead to infl ammatory diseases, obesity, diabetes etc. Althought anatomical sites of a host other than the gut are also colonized by unique microbiota, in this short review, I will focus on the interactions of gut mictobiota and the host immune response in health and diseaseri artacaktır. 2020 ve sonrasına yönelik Malezya’da sağlık reformu yapılması ile ilintili baskılar artmaktadır.

Anahtar Kelimeler

İmmune system, intestinal microbiota, symbiosis

İmmün Sistem ve Barsak Mikrobiyotası

Öz

Çevremizdeki tüm kalıtsal nesnenin belirlenmesi demek olan metagenomik (çevresel tümkalıt) alanındaki yeni bulgular bizim dünya görüşümüzü değiştirmekle kalmadı. Artık kendi vücudumuzu minicanlıları da içeren karışık hücresel bilesimi olarak görüyoruz. Ayrıca, bagisiklik sistemimizi hem sağlıkta hem de hastalık durumlarındaki rolünü yeniden düşünmek zorundayız. Simdi iyice anladık ki, yaşamımız, vücudumuzun çeşitli bölgelerine konuşlanmış ve adina mikrobiyota denilen mikrop topluluklarıyla olan karşılıklı işbirliğine, ortak yasama (simbiyoz) bağlı. Biz, konak (ev sahibi) olarak, doğumdan önce ve sonra vücudumuz katılan ortakçı minicanlıları tanır, onlara yerlerini gösterir, sınırlarını belirtiriz. Vücudumuzdaki bakteri, fungus ve diğer tek hücreli mikrobiyotanın içerdiği tüm genetik madde demek olan mikrobiom, bizim işlevlerimizi etkiler. Tüm hayvanlarda ve bitkilerde mikrobiomun içeriği ve işlevi çok önemli. Bu yüzden bir canlının kendi hücreliyle birlikte taşıdığı mikrobiom, o çevre için benzersiz/biricik bir öge sayılır ki biz buna holobiont diyoruz. Holobiont (konak ve konakçıları), kendi içinde iletişimi ve herkese yarar sağlayan işbirliğini sürdürebilmek için, miyomlarca yıllık birlikte evrilmenin şekillendirdiği /orya çıkardığı araçları kullanır. Normal koşullarda, mikrobiyota, hastalık yapıcı (patojen) minicanlıların vücuda yerleşmeni engeller. Ancak, her ilişkide olabileceği gibi, yanlışlıklar olabilir, isler ters gidebilir. Ya konağın bagisiklik sistemindeki bir aksaklık, ya da minicanlının, kalıtımındaki sik görülen değişiklikler, konak-konakçılar (ortakçılar) arasındaki devingen/haraketli dengeyi bozabilir. Boyle bir dengesizlik (dysbiosis) durumunda mikrobiyotadaki bircok minicanlı hastalık yapıcı etkide bulunabilir ki bunun sonucunda, yangısal (infl ammatory) hastalıklar, aşırı şişmanlık, ya da seker hastaligi oryaya çıkabilir. Bir konağın bağırsak dışındaki mikrobiyotası da önemlidir ama biz bu kısa derlemede, göreceli öneminden ötürü, sağlıktahastalıkta, bağırsak mikrobiyotası ile bagisiklik dizgesi arasındaki ilişkiye odaklanacağız.

Anahtar Kelimeler

İmmün sistem, bağırsak mikrobiyotası, simbiyoz

Kaynakça

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