Integrated metabolomics and network pharmacology to reveal the mechanisms of hydroxysafflor yellow A against acute traumatic brain injury

Abstract

Traumatic brain injury (TBI) has become a leading cause of mortality, morbidity and disability worldwide. Hydroxysafflor yellow A (HSYA) is effective in treating TBI, but the potential mechanisms require further exploration. We aimed to reveal the mechanisms of HSYA against acute TBI by an integrated strategy combining metabolomics with network pharmacology. A controlled cortical impact (CCI) rat model was established, and neurological functions were evaluated. Metabolomics of brain tissues was used to identify differential metabolites, and the metabolic pathways were enriched by MetaboAnalyst. Then, network pharmacology was applied to dig out the potential targets against TBI induced by HSYA. The integrated network of metabolomics and network pharmacology was constructed based on Cytoscape. Finally, the obtained key targets were verified by molecular docking. HSYA alleviated the neurological deficits of TBI. Fifteen potentially significant metabolites were found to be involved in the therapeutic effects of HSYA against acute TBI. Most of these metabolites were regulated to recover after HSYA treatment. We found 10 hub genes according to network pharmacology, which was partly consistent with the metabolomics findings. Further integrated analysis focused on 4 key targets, including NOS1, ACHE, PTGS2 and XDH, as well as their related core metabolites and pathways. Molecular docking showed high affinities between key targets and HSYA. Region-specific metabolic alterations in the cortex and hippocampus were illuminated. This study reveals the complicated mechanisms of HSYA against acute TBI. Our work provides a novel paradigm to identify the potential mechanisms of pharmacological effects derived from a natural compound.

Keywords: Hydroxysafflor yellow A; Mechanisms; Metabolomics; Network pharmacology; Traumatic brain injury.

Graphical abstract

Fig. 1

The schematic flowchart of the integrated strategy. The mechanisms of HSYA against TBI were analyzed by metabolomics of brain tissues (Part 1). Hub genes were extracted by network pharmacology (Part 2). Key metabolites and targets were identified and linked based on Part 1 and 2. These key targets were further verified by molecular docking (Part 3).

Fig. 2

Neurobehavioral scores (A) and body weight changes (B) on day 0, 1 and 3 after injury. All data are expressed as mean ± SD, n = 10, **p < 0.01.

Fig. 3

PLS-DA score plots of HSYA on CCI rats in the cortex (A) and hippocampus (B) on day 1 and 3 after injury.

Fig. 4

The differential metabolites in CCI rats treated by HSYA. (A and B) Venn diagrams of the potential metabolites associated with CCI and HSYA treatment on day 1 and 3. (C and D) The heat maps and fold change dumbbell charts of potential metabolites. Data were calculated by the Pearson correlation method after mean centering and unit variance scaling.

Fig. 5

The metabolic pathways of significant metabolites in the cortex and hippocampus. Node size is based on impact values, node color is based on -log₁₀(p) values. The pathways enriched in BATMAN-TCM are colored by names. The pathways marked in red are statistically different with a p-value < 0.05 in the BATMAN-TCM analysis. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)

Fig. 6

Network pharmacology analysis of HSYA treating TBI. (A) The PPI network of HSYA treatment on TBI. Node color reflects its degree. The nodes with red borders represent the hub genes. (B) The KEGG pathways enrichment analysis by ClueGO. All pathways have a p-value of < 0.05. (C) The GO enrichment analysis of potential targets by ClueGO. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)

Fig. 7

The compound-reaction-enzyme-gene networks of the key metabolites and targets. The red hexagons, grey diamonds, green round rectangle and purple circles represent the active compounds, reactions, proteins and genes, respectively. The key metabolites, proteins and genes were magnified. The pathways with a blue background are significantly regulated in the cortex. The pathways with a red background are significantly regulated in both the cortex and hippocampus. (For interpretation of the references to color in this figure legend, the reader is referred to the web version of this article.)

Fig. 8

The 3D interaction diagrams of HSYA and the key targets.

Fig. 9

The interaction network based on metabolomics and network pharmacology. The first and the second arrow near metabolites from left to right denote changes in CCI vs. sham and HSYA vs. CCI groups, respectively.