KALP BAĞIRSAK EKSENİ

Year 2023, Volume: 14 Issue: 1, 49 - 58, 06.05.2023

Cansu Balıkçı , Gamze Gökçay , Songül Erdoğan , Hasan Erdoğan , Kerem Ural

https://doi.org/10.38137/vftd.1276374

Abstract

Barsak-kalp ekseninde, intestinal epitelyal disfonksiyon, disbiyoz, butirat üreten bakteriler, safra asitleri ve bağırsak mikrobiyotundan türetilen metabolitler gibi çeşitli etkileşimler yer almaktadır. Kalp yetmezliği (KY) bulunan hastalarda, bağırsakta mikrosirkülasyon bozuklukları nedeniyle mukozal malabsorpsiyon, intestinal duvar ödemi ve bariyer disfonksiyonu meydana gelmektedir. Bu durum, perfüzyonun azalması, konjesyonun artması ve sempatik vazokonstriksiyon nedeniyle ortaya çıkmaktadır. İntestinal hasarlı sıkı bağlantı noktaları, intestinal geçirgenliğin artmasına neden olarak toksik, patojenik, immünogenik ve yangısal faktörlerin mukozadan geçerek lokal-sistemik inflamasyona neden olmasına yol açmaktadır. KY ile ilişkili disbiyoz, aşırı bakteriyel üreme, bakteriyel translokasyon ve lipopolisakkarit (LPS), trimetilamin N-oksid (TMAO), p-krezilsülfat (PCS) ve indoksil sülfat (IS) gibi birçok toksik madde oluşumuna neden olmaktadır. Artan intestinal geçirgenlik nedeniyle bu toksik maddeler sistemik dolaşıma ulaşarak, tromboz, trombosit invazyonu, köpük hücre formasyonu ve inflamasyon süreçlerinde rol oynayarak ateroskleroz riskini arttırmaktadır. Bağırsak bariyer bütünlüğünü korumak gibi birçok gastrointestinal etkiye sahip olan kısa zincirli yağ asitlerinden biri olan butirat seviyelerindeki azalma, disbiyozu kötüleştirir ve endotoksinlerin genel dolaşıma ulaşmasına neden olarak köpük hücre formasyonunu teşvik eder ve intestinal bariyer fonksiyonunu bozmaktadır. Bu derleme, mevcut literatür ışığında barsak-kalp eksenindeki fizyo-patolojik süreçler hakkında bilgi sağlamayı amaçlamaktadır.

Keywords

Bağırsak geçirgenliği, Disbiyoz, IS, SCFA, TMAO

GUT-HEART AXIS

Abstract

Many interactions play a role in the gut-heart axis. These include intestinal epithelial dysfunction, dysbiosis, butyrate-producing bacteria, bile acids, and intestinal microbe-derived metabolites. In patients with heart failure (HF), mucosal malabsorption, intestinal wall edema and barrier dysfunction develop as a result of microcirculation disorders in the gut due to decreased perfusion, increased congestion and sympathetically mediated vasoconstriction. Toxic, pathogenic, immunogenic and inflammatory factors, through the increase in intestinal permeability as a result of damaged tight junctions in the intestine, pass through the mucosa and reach the systemic circulation, causing local-systemic inflammation. Many factors that cause dysbiosis by changing the intestinal flora, which are frequently seen in HF, lead to bacterial overgrowth, bacterial translocation and formation of many toxic substances, including lipopolysaccharide (LPS), trimethylamine N-oxide (TMAO), p-cresylsulfate (PCS) and indoxyl sulfate (IS). Depending on the increase in intestinal permeability, these toxic substances reach the systemic circulation; it increases the risk of atherosclerosis by playing a role in thrombosis, platelet invasion, foam cell formation and inflammation processes. Decreased levels of butyrate, one of the short-chain fatty acids that have many effects on the gastrointestinal tract, including maintaining intestinal barrier integrity; It promotes foam cell formation, exacerbates dysbiosis, and plays a role in the disruption of intestinal barrier function, causing endotoxins to reach the general circulation. With this review, it is aimed to inform about the physiopathological processes in the gut-heart axis, in the light of the current literature.

Keywords

Dysbiosis, IS, Intestinal permeability, SCFA, TMAO

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