Salviae Miltiorrhizae Radix et Rhizoma in the treatment of pulmonary fibrosis: bioactive compounds and mechanisms

Pulmonary fibrosis (PF) is a severe lung disease characterized by the gradual replacement of lung tissue with fibrotic scar tissue, leading to impaired lung function and potentially fatal outcomes. The aetiology of PF is complex and involves environmental, genetic, autoimmune, and other factors. Currently, the available treatments only delay disease progression and alleviate symptoms, with no effective cure. In traditional Chinese medicine (TCM), Qi deficiency and blood stasis are recognized as pathological factors in PF, with treatment strategies focused on activating blood circulation, removing blood stasis, and tonifying the lungs and Qi. Salviae Miltiorrhizae Radix et Rhizoma (SM), a TCM, is known for its pharmacological effects, particularly in promoting blood circulation and alleviating blood stasis, making it a common therapeutic agent for PF. Research indicates that SM exerts therapeutic effects through anti-inflammatory, antioxidative, and antifibrotic mechanisms. However, a comprehensive review of the primary bioactive compounds in SM and their mechanisms of action in treating PF is lacking. This review explores the content, extraction methods, biological activity, traditional uses, phytochemistry, pharmacology, and pharmacokinetics of SM and its primary bioactive compounds, including lipid-soluble diterpenes, water-soluble phenolic acids, and Salvia miltiorrhiza polysaccharides. Additionally, this review explores the pharmacological actions and mechanisms of these compounds in treating PF. The goal of this review is to enhance the understanding of SM and PF, while providing insights into the potential development of SM as an alternative therapy for PF.