Abstract

Cerebral ischemia–reperfusion injury (CIRI) is a cerebrovascular disorder with high rates of incidence, disability, and death. It has been identified that Salvia miltiorrhiza and safflower have a protective effect in CIRI. However, the synergistic mechanisms of their multiple active components remain to be elucidated. In this study, we investigated the protective mechanisms of the combination of Tanshinone IIA, salvianic acid A, salvianolic acid B, and hydroxy safflower yellow A in CIRI, based on the TGF-β1/Smad3 signaling pathway. Sprague-Dawley (SD) rats were used to establish the rat middle cerebral artery occlusion/reperfusion (MCAO/R) model using the suture method. Drugs were administered intraperitoneally once daily for 7 consecutive days. Neurological function scores and the volume of brain infarction were evaluated using TTC staining, and the pathological changes in brain tissue were examined using Nissl staining. ELISA kits were used to detect the concentrations of IL-1β, IL-6, and ICAM-1 in serum. At the same time, RT-qPCR, Western blot, and immunohistochemistry were employed to evaluate the mRNA and protein expression of TGF-β1, Smad3, and IL-1β in brain tissue. Following treatment, particularly in the medium-dose group, our findings indicated that neurological deficits and cerebral infarct volume were significantly reduced. Nissl staining revealed improved neuronal morphology and survival in rats with MCAO/R. The levels of pro-inflammatory cytokines (IL-1β, IL-6, and ICAM-1) in serum were significantly decreased. Furthermore, TGF-β1 and Smad3 expression in rat brains were upregulated, while IL-1β expression was downregulated. Taken together, these results indicate that the combination of Tanshinone IIA, salvianic acid A, salvianolic acid B, and hydroxyl safflower yellow A may exhibit a neuroprotective effect on cerebral I/R injury in rats by activating the TGF-β1/Smad3 signaling pathway and subsequently inhibiting the inflammatory response.