Mitohormesis and Regulatory Mechanisms

Yıl 2022, Cilt: 1 Sayı: 1, 21 - 26, 30.12.2022

Elif Şahin , Ahmet Alver

Öz

Hormesis is a process in which exposure to a low dose of a potentially harmful stressor promotes adaptive changes that enable the cell to better tolerate subsequent stress. Mitohormesis is a term used to describe a biological protective response in which the induction of a reduced amount of mitochondrial stress leads to an increase in health and vitality within a cell, tissue or organism. The mitochondrial stress response, activated by a potentially damaging stimulus, requires coordinated communication with the nucleus, known as mitonuclear communication. This communication, caused by the hormetic response in mitochondria, occurs through various signals such as reactive oxygen species (ROS), mitochondrial metabolites, proteotoxic signals, and the release of mitokines. In this paradigm, mild mitochondrial stress triggered by any of a variety of stimuli results in a broad and diverse cytosolic and nuclear response. Although multiple mediators and stress signals have been proposed to activate this protective mechanism, the beneficial consequences of mitohormesis are most likely due to an increase in mitochondrial ROS. Activation of the mitohormetic response has been reported to prolong lifespan in different animal models from worms to mammals. In addition, mitohormesis contributes to the health of the organism, especially by improving the metabolism and immune system.

Anahtar Kelimeler

Mitochondria, PGC1α, ROS, UPRmt

Mitohormesis ve Düzenlenme Mekanizmaları

Öz

Hormesis, düşük dozda potansiyel olarak zararlı bir stres etkenine maruz kalmanın, hücrenin sonraki stresi daha iyi tolere etmesini sağlayan adaptif değişiklikleri teşvik ettiği bir süreçtir. Mitohormesis ise, azaltılmış miktarda mitokondriyal stresin indüklenmesinin bir hücre, doku veya organizma içinde sağlık ve canlılıkta bir artışa yol açtığı biyolojik koruyucu bir yanıtı tanımlamak için kullanılan bir terim olarak karışımıza çıkmaktadır. Potansiyel olarak zarar verici bir uyaran tarafından aktive edilen mitokondriyal stres yanıtı, mitonükleer iletişim olarak bilinen çekirdek ile koordineli bir iletişim gerektirir. Mitokondrideki hormetik yanıtın neden olduğu bu iletişim, reaktif oksijen türleri (ROS), mitokondriyal metabolitler, proteotoksik sinyaller ve mitokinlerin salınımı gibi çeşitli sinyaller aracılığıyla meydana gelir. Bu paradigmada, çeşitli uyaranlardan herhangi biri tarafından tetiklenen hafif mitokondriyal stres, geniş ve çeşitli bir sitozolik ve nükleer tepki ile sonuçlanır. Bu koruyucu mekanizmayı aktive etmek için çoklu aracılar ve stres sinyalleri önerilmiş olsa da, mitohormesisin faydalı sonuçları büyük olasılıkla mitokondriyal ROS'taki bir artıştan dolayı meydana gelmektedir. Mitohormetik yanıtın aktive edilmesinin solucanlardan memelilere kadar farklı hayvan modellerinde yaşam süresini uzattığı belirtilmiştir. Ayrıca mitohormesis, özellikle metabolizmayı ve bağışıklık sistemini geliştirerek organizmanın sağlığını da katkıda bulunmaktadır.

Anahtar Kelimeler

Mitokondri, PGC1α, ROS, UPRmt

Kaynakça

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