MaiJiTong granule attenuates atherosclerosis by reducing ferroptosis via activating STAT6-mediated inhibition of DMT1 and SOCS1/p53 pathways in LDLR-/- mice.

BACKGROUND AND PURPOSE: Atherosclerosis is the primary pathological basis of cardiovascular disease. Ferroptosis is a regulated form of cell death, a process of lipid peroxidation driven by iron, which can initiate and promote atherosclerosis. STAT6 is a signal transducer that shows a potential role in regulating ferroptosis, but, the exact role in ferroptosis during atherogenesis remains unclear. The Traditional Chinese Medicine Maijitong granule (MJT) is used for treating cardiovascular disease and shows a potential inhibitory effect on ferroptosis. However, the antiatherogenic effect and the underlying mechanism remain unclear. In this study, we determined the role of STAT6 in ferroptosis during atherogenesis, investigated the antiatherogenic effect of MJT, and determined whether its antiatherogenic effect was dependent on the inhibition of ferroptosis. METHODS: 8-week-old male LDLR-/- mice were fed a high-fat diet (HFD) at 1st and 10th week, respectively, to assess the preventive and therapeutic effects of MJT on atherosclerosis and ferroptosis. Simultaneously, the anti-ferroptotic effects and mechanism of MJT were determined by evaluating the expression of genes responsible for lipid peroxidation and iron metabolism. Subsequently, we reanalyzed microarray data in the GSE28117 obtained from cells after STAT6 knockdown or overexpression and analyzed the correlation between STAT6 and ferroptosis. Finally, the STAT6-/- mice were fed HFD and injected with AAV-PCSK9 to validate the role of STAT6 in ferroptosis during atherogenesis and revealed the antiatherogenic and anti-ferroptotic effect of MJT. RESULTS: MJT attenuated atherosclerosis by reducing plaque lesion area and enhancing plaque stability in both preventive and therapeutic groups. MJT reduced inflammation via suppressing inflammatory cytokines and inhibited foam cell formation by lowering the LDL level and promoting ABCA1/G1-mediated lipid efflux. MJT ameliorated the ferroptosis by reducing lipid peroxidation and iron dysregulation during atherogenesis. Mechanistically, STAT6 negatively regulated ferroptosis by transcriptionally suppressing SOCS1/p53 and DMT1 pathways. MJT suppressed the DMT1 and SOCS1/p53 via stimulating STAT6 phosphorylation. In addition, STAT6 knockout exacerbated atherosclerosis and ferroptosis, which abolished the antiatherogenic and anti-ferroptotic effects of MJT. CONCLUSION: STAT6 acts as a negative regulator of ferroptosis and atherosclerosis via transcriptionally suppressing DMT1 and SOCS1 expression and MJT attenuates atherosclerosis and ferroptosis by activating the STAT6-mediated inhibition of DMT1 and SOCS1/p53 pathways, which indicated that STAT6 acts a novel promising therapeutic target to ameliorate atherosclerosis by inhibiting ferroptosis and MJT can serve as a new therapy for atherosclerosis treatment.

Anti-atherosclerotic effects of naringenin and quercetin from Folium Artemisiae argyi by attenuating Interleukin-1 beta (IL-1ß)/ matrix metalloproteinase 9 (MMP9): network pharmacology-based analysis and validation.

Effective components and related target genes of Folium Artemisiae argyi were screened from Traditional Chinese Medicines for Systems Pharmacology Database and Analysis Platform. The therapeutic targets of atherosclerosis were searched in the MalaCards and OMIM databases. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis were performed in WebGestalt online and verified according to ClueGo and Pedia apps in Cytoscape. Then, the protein-protein interaction network was analyzed using the STRING database and constructed using Cytoscape. Differential expression of target genes was identified in GSE9128 and GSE71226 by GEO2R. And then, molecular docking was performed using the Molecular Operating Environment. Finally, we validated the protein expression of Interleukin-6 (IL-6)/IL-1ß /MMP9 by qRT-PCR and Western blot in Raw264.7 which was induced by LPS. A total of 232 potential target genes and 8 ingredients of Folium Artemisiae argyi were identified. Quercetin and naringenin are potential candidate bioactive agents in treating atherosclerosis. Vascular endothelial growth factor (VEGFA), MMP9 and IL-1ß could be potential target genes. KEGG analysis demonstrated that the fluid shear stress and atherosclerosis pathway play a crucial role in the anti-atherosclerosis effect of Folium Artemisiae argyi. Gene Expression Omnibus (GEO) validation demonstrated that VEGFA was downregulated, while MMP9 and IL-1ß were upregulated in patients with atherosclerosis. Molecular docking suggested that only MMP9 had a good combination with quercetin. The cell experiment results suggested that naringenin and quercetin have strong anti-inflammation effects, and significantly inhibit the expression of MMP9. Practical ApplicationsArtemisiae argyi is a traditional Chinese herbal medicine that has been widely used for its antibacterial and anti-inflammatory effects. This research demonstrated the bioactive ingredients, potential targets, and molecular mechanism of Folium Artemisiae argyi in treating atherosclerosis. It also suggests a reliable approach in investigating the therapeutic effect of traditional Chinese herbal medicine in treating Atherosclerotic cardiovascular disease (ASCVD).

GLSP and GLSP-derived triterpenes attenuate atherosclerosis and aortic calcification by stimulating ABCA1/G1-mediated macrophage cholesterol efflux and inactivating RUNX2-mediated VSMC osteogenesis.

Background and Purpose: Atherosclerosis is the main pathophysiological foundation of cardiovascular disease, which was caused by inflammation and lipid metabolism disorder, along with vascular calcification. Aortic calcification leads to reduced plaque stability and eventually causes plaque rupture which leads to cardiovascular events. Presently, the drug to treat aortic calcification remains not to be available. Ganoderma lucidum spore powder (GLSP) is from Ganoderma lucidum which is a Traditional Chinese Medicine with the homology of medicine and food. It has multiple pharmacological effects, but no research on aortic calcification during atherosclerosis was performed. This study investigated the effects of GLSP on atherosclerosis and aortic calcification and revealed the underlying mechanism. Methods: In vivo, 8-week-aged male LDLR-/- mice were fed a high-fat diet to induce atherosclerosis along with aortic calcification. Simultaneously, the mice were treated with GLSP at the first week of HFD feeding to determine the protection against early and advanced atherosclerosis. Subsequently, the mice tissues were collected to evaluate the effects of GLSP on atherosclerosis, and aortic calcification, and to reveal the underlying mechanism. In vitro, we determined the major components of GLSP triterpenes by HPLC, and subsequently assessed the protective effects of these main active components on lipid metabolism, inflammation, and calcification in RAW264.7 and HASMC cells. Results: We observed GLSP attenuated plaque area and aortic calcification in the mice with early and advanced atherosclerosis. GLSP reduced the number of foam cells by improving ABCA1/G1-mediated cholesterol efflux in macrophages. In addition, GLSP protected against the aortic endothelium activation. Moreover, GLSP inhibited aortic calcification by inactivating RUNX2-mediated osteogenesis in HASMCs. Furthermore, we determined the major components of GLSP triterpenes, including Ganoderic acid A, Ganoderic acid B, Ganoderic acid C6, Ganoderic acid G, and Ganodermanontriol, and found that these triterpenes promoted ABCA1/G1-mediated cholesterol efflux and inhibited inflammation in macrophage, and inactivated RUNX2-mediated osteogenesis in VSMC. Conclusions: This study demonstrates that GLSP attenuates atherosclerosis and aortic calcification by improving ABCA1/G1-mediated cholesterol efflux and inactivating RUNX2-mediated osteogenesis in LDLR-/- mice. GLSP may be a potential drug candidate for the treatment of atherosclerosis and vascular calcification.

Role of the CCL2-CCR2 axis in cardiovascular disease: Pathogenesis and clinical implications.

The CCL2-CCR2 axis is one of the major chemokine signaling pathways that has received special attention because of its function in the development and progression of cardiovascular disease. Numerous investigations have been performed over the past decades to explore the function of the CCL2-CCR2 signaling axis in cardiovascular disease. Laboratory data on the CCL2-CCR2 axis for cardiovascular disease have shown satisfactory outcomes, yet its clinical translation remains challenging. In this article, we describe the mechanisms of action of the CCL2-CCR2 axis in the development and evolution of cardiovascular diseases including heart failure, atherosclerosis and coronary atherosclerotic heart disease, hypertension and myocardial disease. Laboratory and clinical data on the use of the CCL2-CCR2 pathway as a targeted therapy for cardiovascular diseases are summarized. The potential of the CCL2-CCR2 axis in the treatment of cardiovascular diseases is explored.

Exploring Ganweikang Tablet as a Candidate Drug for NAFLD Through Network Pharmacology Analysis and Experimental Validation.

Nonalcoholic fatty liver disease (NAFLD) is defined as liver disease in which more than 5% of hepatocytes are steatotic with little or no alcohol consumption. NAFLD includes benign nonalcoholic fatty liver (NAFL) and nonalcoholic steatohepatitis (NASH). Importantly, NASH is an advanced progression of NAFL and is characterized by steatosis, hepatocyte ballooning, lobular inflammation, and fibrosis. However, to date, no drugs specifically targeting NAFLD have been approved by the FDA. Therefore, a new drug or strategy for NAFLD treatment is necessary. However, the pathogenesis of NAFLD is complex and no single-target drugs have achieved the desired results. Noticeably, traditional Chinese medicine formulations are a complex system with multiple components, multiple targets, and synergistic effects between components. The Ganweikang tablet is a compound formula based on traditional Chinese medicine theory and clinical experience. In this study, network pharmacology analysis indicates Ganweikang tablet as a candidate for NAFLD treatment. Furthermore, we evaluated the therapeutic effects of Ganweikang tablet on the NAFL and NASH and tried to clarify the underlying molecular mechanisms in animal models and cell experiments. As expected, Ganweikang tablet was found to improve NAFL and NASH by modulating inflammation, apoptosis, and fatty acid oxidation by inhibiting NFκB, caspase-8, and activating PPARα, which not only indicates that Ganweikang tablet as a drug candidate but also provides a theoretical basis of Ganweikang tablet for the treatment of NAFL and NASH.

The Induction of Endothelial Autophagy and Its Role in the Development of Atherosclerosis.

Increasing attention is now being paid to the important role played by autophagic flux in maintaining normal blood vessel walls. Endothelial cell dysfunction initiates the development of atherosclerosis. In the endothelium, a variety of critical triggers ranging from shear stress to circulating blood lipids promote autophagy. Furthermore, emerging evidence links autophagy to a range of important physiological functions such as redox homeostasis, lipid metabolism, and the secretion of vasomodulatory substances that determine the life and death of endothelial cells. Thus, the promotion of autophagy in endothelial cells may have the potential for treating atherosclerosis. This paper reviews the role of endothelial cells in the pathogenesis of atherosclerosis and explores the molecular mechanisms involved in atherosclerosis development.

Calycosin ameliorates atherosclerosis by enhancing autophagy via regulating the interaction between KLF2 and MLKL in apolipoprotein E gene-deleted mice.

BACKGROUND AND PURPOSE: Atherosclerosis is one of the underlying causes of cardiovascular disease. Formation of foam cells and necrotic core in the plaque is a hallmark of atherosclerosis, which results from lipid deposition, apoptosis, and inflammation in macrophages. Macrophage autophagy is a critical anti-atherogenic process and defective autophagy aggravates atherosclerosis by enhancing foam cell formation, apoptosis, and inflammation. Hence, enhancing autophagy can be a strategy for atherosclerosis treatment. Calycosin, a flavonoid from Radix Astragali, displays anti-oxidant and anti-inflammatory activities and therefore is potential to reduce the risk of cardiovascular disease. However, the anti-atherogenic effect of calycosin and the involved mechanism remains unclear. In this study, we assessed the potential benefits of calycosin on autophagy and atherosclerosis, and revealed the underlying mechanism. EXPERIMENTAL APPROACH: In this study, apoE-/- mice were fed high-fat diet for 16 weeks in the presence of calycosin and/or autophagy inhibitor chloroquine, which was followed by determination of atherosclerosis development, autophagy activity, and involved mechanisms. KEY RESULTS: Calycosin protected against atherosclerosis and enhanced plaque stability via promoting autophagy. Calycosin inhibited foam cell formation, inflammation, and apoptosis by enhancing autophagy. MLKL was demonstrated as a new autophagy regulator, which can be negatively regulated by KLF2. Mechanistically, inhibitory effects of calycosin on atherogenesis were via improved autophagy through KLF2-MLKL signalling pathway modulation. CONCLUSIONS AND IMPLICATIONS: This study demonstrated the atheroprotective effect of calycosin was through upregulating KLF2-MLKL-mediated autophagy, which not only proposed novel mechanistic insights into t atherogenesis but also identified calycosin as a potential drug candidate for atherosclerosis treatment.

Metformin attenuates atherosclerosis and plaque vulnerability by upregulating KLF2-mediated autophagy in apoE-/- mice.

Atherosclerosis is a chronic lipid disfunction and inflammatory disease, which is characterized with enriched foam cells and necrotic core underneath the vascular endothelium. Therefore, the inhibition of foam cell formation is a critical step for atherosclerosis treatment. Metformin, a first-line treatment for Type 2 diabetes, is reported to be beneficial to cardiovascular disease. However, the mechanism underlying the antiatherogenic effect of metformin remains unclear. Macrophage autophagy is reported to be a highly anti-atherogenic process that promotes the catabolism of cytosolic lipid to maintain cellular lipid homeostasis. Notably, dysfunctional autophagy in macrophages plays a detrimental role during atherogenesis. Krueppel-like factor 2 (KLF2) is an important transcription factor that functions as a key regulator of the autophagy-lysosome pathway. While the role of KLF2 in foam cell formation during the atherogenesis remains elusive. In this study, we first investigated whether metformin could protect against atherogenesis via enhancing autophagy in high fat diet (HFD)-induced apoE-/- mice. Subsequently, we further determined the molecular mechanism that whether metformin could inhibit foam cell formation by activating KLF2-mediated autophagy. We show that metformin protected against HFD-induced atherosclerosis and enhanced plaque stability in apoE-/- mice. Metformin inhibits foam cell formation and cellular apoptosis partially through enhancing autophagy. Mechanistically, metformin promotes autophagy via modulating KLF2 expression. Taken together, our study demonstrates a novel antiatherogenic mechanism of metformin by upregulating KLF2-mediated autophagy.

Contradictory regulation of macrophages on atherosclerosis based on polarization, death and autophagy.

The main pathological feature of atherosclerosis is lipid metabolism disorder and inflammation. Macrophages, as the most important immune cells in the body, run through the beginning and end of disease development. After macrophages overtake the atherosclerosis-susceptible area apolipoprotein low-density lipoprotein ox-LDL, they transform into foam cells that adhere to blood vessels and recruit a large number of pro-inflammatory factors to initiate the disease. Promoting the outflow of lipids in foam cells and alleviating inflammation have become the basic ideas for the study of atherosclerosis treatment strategies. The polarization of macrophages refers to the estimation of the activation of macrophages at a specific point in space and time. Determining the proportion of different macrophage phenotypes in the plaque can help identify delay or prevent disease development. However, the abnormal polarization of macrophages and the accumulation of lipid also affect the growth state of cells to some extent, thus aggravate the influence on plaque area and stability. Besides, overactive or deficient autophagy of macrophages may also lead to cell death and participate in lipid metabolism and inflammation regression. In this paper, the role of macrophages in atherosclerosis was discussed from three aspects: polarization, death, and autophagy.

Astragalus Flavone Ameliorates Atherosclerosis and Hepatic Steatosis Via Inhibiting Lipid-Disorder and Inflammation in apoE-/- Mice.

Atherosclerosis is a major pathogenic driver of cardiovascular diseases. Foam cell formation plays a key role in atherogenesis, which is affected by lipid disorder and inflammation. Therefore, inhibition of foam cell formation is a therapeutic approach for atherosclerosis treatment. Total flavone of Astragalus membranaceus (TFA) is extracted from A. membranaceus that has protective effect on cardiovascular disease. However, the effect of TFA on atherosclerosis and the underlying mechanism remains unknown. In this study, we determined whether TFA could inhibit atherosclerosis and uncovered the underlying mechanism. In vivo, ApoE deficient mice were treated with TFA and high-fat diet for 16 weeks. Subsequently, atherosclerotic lesions, hepatic steatosis and associated genes expression in vitro and in vivo were determined. We found that TFA reduced atherosclerotic lesion size and enhanced plaque stability, which might be attributed to improved lipid disorder, reduced inflammation and decreased monocyte adhesion. Mechanistically, TFA inhibited hepatic steatosis via regulating the genes responsible for lipid metabolism, by which ameliorating the lipid disorder. Moreover, in macrophage, TFA reduced the expression of scavenger receptors such as CD36 and SRA; and promoted the expression of ATP-binding cassette transporter A1 and G1 (ABCA1/G1). More importantly, TFA reduced miR-33 expression and dampened NFκB activity, by which de-repressing ABCA1/G1 activity and inhibiting the inflammation. Collectively, TFA can attenuate atherosclerosis via dual suppression of miR-33 and NFκB pathway, and partially through inhibition of scavenger receptors in macrophage. In addition, TFA ameliorates the hepatic steatosis and lipid disorder, which in turn contributes to the amelioration of atherosclerosis, suggesting that TFA might be a novel therapeutic approach for inhibition of atherosclerosis and hepatic steatosis.