Research Progress on the Role and Mechanisms of Traditional Chinese Medicine in Preventing and Treating Radiation-induced Lung Injury via the TGF-β/Smad Signaling Pathway

Radiation-induced lung injury(RILI), a disease primarily characterized by radiation-induced pneumonitis(RP) and radiation-induced pulmonary fibrosis(RPF), is a common complication following thoracic radiotherapy, significantly impairing patients’ quality of life. The transforming growth factor-β(TGF-β)/Smad signaling pathway and its regulated cytokines are closely associated with the occurrence and development of RILI. Various traditional Chinese medicine(TCM) and their active components can inhibit the activation of inflammatory factors, reduce extracellular matrix(ECM) synthesis and collagen deposition by regulating this signaling pathway, thereby alleviating inflammatory infiltration and fibrosis in lung tissue and improving lung function. Research has demonstrated that TCM exerts multiple effects, including immunomodulatory, antioxidant, metabolic regulatory, anti-inflammatory, and anti-fibrosis. Its pharmacological mechanisms in the prevention and treatment of RILI have been extensively studied. However, the specific active components and mechanisms of TCM and its compound formulas in treating RILI remain unclear, and the synergistic effects among multiple pathways urgently need to be addressed. This review summarizes the research progress on the TGF-β/Smad signaling pathway in the prevention and treatment of RILI with TCM, providing a reference for the clinical application and fundamental research of TCM in RILI. It also offers a theoretical basis for promoting the clinical translation of TCM and exploring innovative therapeutic strategies for RILI.