In a recent study published in the journal Frontiers in Pharmacology, researchers in China identified and analyzed garlic's active components and their targets in atherosclerosis while investigating the underlying pharmacological mechanisms. They found that garlic lowers the expression of ferroptosis-related genes, indicating its potential application in treating atherosclerosis by regulating ferroptosis and reducing lipid peroxidation.
Study: Garlic ameliorates atherosclerosis by regulating ferroptosis pathway: an integrated strategy of network pharmacology, bioinformatic and experimental verification. Image Credit: greanggrai hommalai / Shutterstock
Background
Atherosclerosis is a leading cause of cardiovascular diseases (CVDs) like ischemic heart disease and stroke, with abnormal carotid intimal thickening affecting over a billion people globally. The disease stems from lipid metabolism disorders, leading to plaque formation and potential artery occlusion due to plaque rupture. Emerging evidence sheds light on the role of ferroptosis, a form of regulated cell death linked to lipid peroxidation, in atherosclerosis and other CVDs. While lipid-lowering drugs exist, they carry risks like liver and kidney damage, emphasizing the need for safer treatments.
Garlic, a widely used herbal supplement, is noted for its cardiovascular benefits, particularly in reducing oxidative stress and inflammation, which are critical in atherosclerosis. Its active components, such as allicin, may inhibit lipid peroxidation and ferroptosis. Despite its known benefits, the precise mechanisms of garlic's effects on atherosclerosis remain unclear. Network pharmacology and molecular docking analyses can be employed to investigate garlic's multi-target mechanisms, aiming to develop new, effective drugs for atherosclerosis prevention and treatment. In the present study, researchers investigated the mechanisms by which garlic improves atherosclerosis using a combination of network pharmacology, bioinformatics, molecular docking, and experimental validation.
About the study
The primary pharmacological targets and active components of garlic, together called the garlic-associated drug targets, were obtained from three databases: Traditional Chinese Medicine Systems Pharmacology Database (TCMSP), Traditional Chinese Medicine Information Database (TCM-ID), and Encyclopedia of Traditional Chinese Medicine (ETCM). Potential atherosclerosis gene targets were obtained from the following databases: DisGeNET, GeneCards, and DiGSeE. An intersection analysis of these data was performed to identify potential target genes of garlic for treating atherosclerosis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses of these genes were performed. An interaction network was created among garlic components, therapeutic targets, and major signaling pathways. Gene expression differences in arteries between healthy individuals and those with atherosclerosis were analyzed using various databases. Additionally, molecular docking of garlic's active components with key genes was performed.
Experimental verification involved cell experiments with mouse cells for cytotoxicity, biochemical assays, Oil red O staining, and Western blotting. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was conducted to measure gene expression levels. Further, mouse models were divided into four groups: sham operation group, model group, allicin treatment group, and negative control group. Biochemical assays were performed on serum samples, and histological changes were observed.
Results and discussion
A total of 16 active garlic components and 503 potential targets were identified. Additionally, 3,033 key targets for atherosclerosis were found. By intersecting garlic's targets with atherosclerosis targets, 230 potential therapeutic targets were identified. Pathway enrichment analyses revealed 2017 biological processes, 78 cellular components, and 200 molecular functions. Significant processes included response to oxidative stress and inflammation. Potential targets were found to be enriched in lipid metabolism and atherosclerosis pathways.
Molecular docking studies demonstrated that garlic components like sobrol A, benzaldoxime, allicin, and (+)-L-alliin interact strongly with ferroptosis-related proteins such as GPX4 (glutathione peroxidase), DPP4 (dipeptidyl peptidase 4), and ALOX5 (arachidonate 5-lipoxygenase). In animal models, specifically, apolipoprotein E knockout and C57BL/6 mice, allicin was shown to significantly reduce plaque formation and lipid deposition in the carotid artery. Allicin was also found to improve lipid profiles, given by the lower concentrations of low-density lipoprotein cholesterol (LDL-C), total cholesterol, and triglycerides in the treated group as compared to the untreated group. Allicin was found to mitigate lipid peroxidation and iron death, as shown by reduced levels of malondialdehyde and increased GPX4 in the serum.
In in vitro experiments, Allicin was found to decrease oxidative damage caused by ox-LDL. The protein expression of ferroptosis-related genes DPP4 and ALOX5 was found to reduce with allicin treatment, while GPX4 expression was found to increase. Additionally, allicin was found to lower ALOX5 messenger ribonucleic acid (mRNA) levels and increased GPX4 mRNA levels compared to the ox-LDL group. These findings suggest that garlic, especially allicin, may improve atherosclerosis by regulating ferroptosis, highlighting its potential therapeutic value in CVD management.
Conclusion
In conclusion, the study highlights the potential of garlic and its active compounds, such as sobrol A, allicin, (+)-L-alliin, and benzaldoxime, in treating atherosclerosis by targeting ferroptosis-related mechanisms. The specific gene targets identified in the study provide a basis for designing targeted therapies that could enhance treatment outcomes in the future. The findings warrant further research into garlic-based therapies, which could potentially lead to more effective, natural treatment options for CVDs.
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