ABSTRACT

Autophagy is a fundamental process of intracellular degradation of damaged organelles and proteins. Autophagy is also a crucial mechanism for adaptation to stress, survival and cellular homeostasis. Paradoxically, autophagy can also promote cell death, but when and how autophagy may have pro- or anti-apoptotic functions is still unknown. Autophagy involves the recruitment and degradation of damaged organelles, protein aggregates, long-lived proteins and pathogens, into double membrane vesicles called autophagosomes which then fuse with the lysosome to form autolysosomes. Alterations in autophagy have been implicated in a wide range of disorders including lung diseases. In this review, we discuss what is currently known about the role of autophagy in the initiation and progression of different pulmonary disorders. Some studies indicate that autophagy could have a deleterious role in the pathogenesis of chronic obstructive pulmonary disease and asthma. In other disorders, such as idiopathic pulmonary fibrosis and cystic fibrosis, impaired autophagy may contribute to pathogenesis.

KEYWORDS

Apoptosis, asthma, autophagy, homeostasis, chronic obstructive pulmonary disease, idiopathic pulmonary fibrosis, cystic fibrosis.

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