Synergistic Effects of Guan-Xin-Er-Hao and Hydroxysafflor Yellow A on Atherosclerosis in ApoE-/- Mice: Unveiling Antioxidant and Anti-Inflammatory Mechanisms

Background: The Guan-Xin-Er-Hao (GXII) decoction, a traditional Chinese medicine, contains hydroxysafflor yellow A (HSYA) as its main active compound for treating coronary heart disease. Objectives: This study aimed to assess the therapeutic efficacy of HSYA compared to GXII and elucidate its molecular mechanisms in combating atherosclerosis. Materials and Methods: Guan-Xin-Er-Hao (GXII) was analyzed using HPLC-MS, which identified three main absorbable components: Hydroxysafflor Yellow A (HSYA), Ferulic Acid and Tanshinol. Among them, HSYA demonstrated the most pronounced effects in the in vitro experiments, leading to its selection for subsequent in vivo studies due to its high content and superior bioavailability within GXII. ApoE−/− mice were fed a high-fat diet for eight weeks and treated orally with GXII or HSYA. Atherosclerotic plaque areas and plasma lipid levels served as indicators of anti-atherosclerotic activity. Oxidative stress markers (malondialdehyde, superoxide dismutase, glutathione peroxidase, catalase) and inflammatory mediators (tumor necrosis factor-α, vascular cell adhesion molecule-1, interleukin-1β) were evaluated using enzyme-linked immunosorbent assays, western blotting and reverse transcription-polymerase chain reaction. Results: The Contribution Rate (CR) analysis indicated that HSYA significantly influenced serum lipid levels, oxidative stress markers and inflammatory protein/mRNA levels, with HSYA demonstrating a CR exceeding 90% relative to GXII. These findings underscore HSYA's predominant role within GXII in exerting anti-atherosclerotic effects through mitigation of oxidative stress and inflammation. Conclusion: The synergistic actions of GXII and HSYA reveal a promising therapeutic approach for atherosclerosis, offering valuable insights into their antioxidant and anti-inflammatory mechanisms in ApoE−/− mice.