Naoxintong Capsule inhibits endothelial cell injury by regu-lating the generation and function of circulating exosomes

Cardiovascular disease poses a serious threat to the health of middle-aged and elderly people worldwide. It has been shown that the pre-progression of cardiovascular disease is usually ac-companied by endothelial injury, oxidative stress and inflammatory responses, so attention to the protection of injured endothelium is particularly important for the early control and treatment of vascular disease. Circulating exosomes belong to a type of extracellular vesicles with substance transport and signaling roles that act as regulatory mediators and play a great advantage in various diseases treatment. Naoxintong capsule (NXT) is a Chinese medicine with good clinical efficacy in alleviating the progression of cardiovascular diseases. However, the role of circulating exosomes in the treatment of endothelial injury by NXT remains unexplored. Here, we reported the protective effect of NXT on endothelial damage through circulating exosomes. Our results showed that cir-culating exosomes of serum from NXT-treated rats (NXT-EXO) had effects on damaged endothelial cells (ECs) by attenuating apoptosis, inhibiting inflammation and reducing oxidative stress, whereas circulating exosomes of serum from blank-treated rats (Ctl-EXO) had no significant effect. Thus, this study elucidated that circulating exosome played a key role in the efficacy of NXT in protecting against endothelial injury, which may have important implications for the functional studies of circulating exosomes and the clinical diagnosis and treatment of vascular diseases.