Mikrobiyota ve Ruh Sağlığı İlişkisi: Bütüncül Bir Bakış

Öz

İnsan bağırsağındaki mikroorganizmalar, mikrobiyota–bağırsak–beyin ekseni aracılığıyla beyin işlevlerini ve ruh sağlığını düzenlemektedir. Bu çift yönlü iletişim ağı; sinirsel (örn. vagus siniri), endokrin (örn. kortizol, serotonin), immün (örn. sitokinler) ve mikrobiyal metabolit (örn. kısa zincirli yağ asitleri) yollarını kapsamaktadır. Son dönem çalışmalar, bağırsak mikrobiyotasındaki dengesizliğin depresyon, anksiyete, otizm spektrum bozuklukları, şizofreni, bipolar bozukluk ve travma sonrası stres bozukluğu gibi psikiyatrik bozuklukların patogenezinde rol oynadığını ortaya koymaktadır. Azalmış mikrobiyal çeşitlilik, yararlı kısa zincirli yağ asidi üreten bakterilerin tükenmesi ve proinflamatuvar taksonların artışı ile karakterize olan değişmiş mikrobiyal profillerin, nöropsikiyatrik semptomatoloji ile tutarlı biçimde ilişkili olduğu saptanmıştır. Çalışmalar, probiyotikler, prebiyotikler ve diyet değişiklikleri gibi mikrobiyota temelli müdahalelerin ruh sağlığı üzerinde etkili olabileceğini göstermekte; bu da "psikobiyotikler" kavramının ortaya çıkmasına yol açmaktadır. Bu derleme, bağırsak mikrobiyotası ile psikiyatrik bozukluklar arasındaki ilişkiyi açıklayan mekanistik temellere dair kapsamlı bir sentez sunmakta ve mikrobiyota temelli stratejilerin terapötik potansiyelini değerlendirmektedir. Ayrıca, kişiye özel psikobiyotik tedaviler, bağırsak mikrobiyotasından türetilmiş biyobelirteçler ve bunların psikiyatrik bakımda pratik uygulamaları gibi yeni gelişmeleri de incelemektedir. Bütüncül bir bakış açısını benimseyen bu çalışma, disiplinler arası etkileşimi güçlendirmeyi ve bağırsak ile beyin arasındaki dinamik ilişkinin temellerine dayalı bütünleşik ruh sağlığı yaklaşımlarının gelişimine katkı sağlamayı amaçlamaktadır.

Anahtar Kelimeler

• mikrobiyota-bağırsak-beyin ekseni
• psikobiyotikler
• psikiyatrik bozukluklar
• ruh sağlığı

Relationship Between Microbiota and Mental Health: A Holistic View

Abstract

The microorganisms in the human intestine regulate brain function and mental health through the microbiota-gut-brain axis. This bidirectional communication network encompasses neural (e.g., vagus nerve), endocrine (e.g., cortisol, serotonin), immune (e.g., cytokines), and microbial metabolite (e.g., short-chain fatty acids) pathways. Recent studies highlight the role of gut dysbiosis in the pathogenesis of psychiatric disorders such as depression, anxiety, autism spectrum disorders, schizophrenia, bipolar disorder, and post-traumatic stress disorder. Altered microbial profiles—marked by reduced microbial diversity, depletion of beneficial short-chain fatty acids-producing bacteria, and increased pro-inflammatory taxa—have been consistently associated with neuropsychiatric symptomatology. Studies have shown that microbiota interventions such as probiotics, prebiotics and dietary changes can affect mental health, giving rise to the concept of 'psychobiotics'. This narrative review presents a comprehensive synthesis of the mechanistic underpinnings linking gut microbiota to psychiatric disorders and evaluates the therapeutic potential of microbiota-based strategies. It also explores new developments such as tailored psychobiotic treatments, biomarkers derived from the gut microbiota, and their practical applications in psychiatric care. By adopting an integrative perspective, this review aims to bridge disciplines and foster the development of holistic mental health care approaches grounded in the dynamic interplay between the gut and the brain.

Keywords

• microbiota-gut-brain axis
• psychobiotics
• psychiatric disorders
• mental health

Kaynakça

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