Rutaecarpine, Isolated from Evodia rutaecarpa, Inhibits Epithelial-Mesenchymal Transition and Cellular Senescence in a Mouse Model of Pulmonary Fibrosis

Cellular senescence, a type of cytostasis, is the irreversible inhibition of the natural cell division in proliferating cells, resulting from various cellular stresses, including telomere shortening, DNA damage, mitochondrial dysfunctions, and pro-inflammatory responses. While cellular senescence can facilitate beneficial physiological processes such as tissue repair and wound healing, senescent cells also contribute to pathophysiological processes of age-related diseases, including fibrotic lung diseases. The cellular senescence model and co-culture system were established to explore the underlying mechanisms associated with cellular senescence and fibrosis. Rutaecarpine is a bioactive alkaloid isolated from Evodia rutaecarpa (Rutaceae), a traditional herbal medicine. Rutaecarpine enhanced the promotor activity of E-cadherin, reduced TGF-β-induced reorganization of the actin cytoskeleton, and finally inhibited epithelial-mesenchymal transition. Rutaecarpine also attenuated fibrotic and senescence features in bleomycin-induced lung fibrosis model. Here, we suggest the relevance between senescence and fibrosis, and a potential therapeutic approach of targeting senescence to attenuate lung fibrosis development.