Shear Stress in Autophagy and Its Possible Mechanisms in the Process of Atherosclerosis

Elevated circulating LncRNA NORAD fosters endothelial cell growth and averts ferroptosis by modulating the miR-106a/CCND1 axis in CAD patients

Atherosclerosis is a leading cause of cardiovascular diseases, characterized by endothelial dysfunction and lipid accumulation. Long non-coding RNAs (lncRNAs) are emerging as key regulators of endothelial cell behavior. This study aimed to investigate the role of lncRNA NORAD in endothelial cell proliferation and as a potential therapeutic target for atherosclerosis. A total of 75 CAD patients and 76 controls were recruited, and plasma NORAD levels were measured using qRT-PCR. HUVECs were transfected with si-NORAD to evaluate its effects on cell cycle, proliferation, migration, and apoptosis. Plasma NORAD levels were significantly elevated in CAD patients. The NORAD-miRNA-mRNA ceRNA regulatory network was constructed based on GEO database, and G1/S-specific cyclin-D1 (CCND1) was identified as one of the hub factors. NORAD deficiency suppressed cell migration and induced G1 cell cycle arrest in HUVECs by downregulating CCND1 in vitro. NORAD upregulated CCND1 in HUVECs via sponging miR-106a that inhibited cell migration. The dual-luciferase assay confirmed the direct targeting of miR-106a by NORAD, and overexpression of miR-106a inhibited HUVEC proliferation and migration. Si-NORAD transfection resulted in induced early apoptosis, increased intracellular ROS levels, decreased GSH levels, and reduced mitochondrial membrane potential. Additionally, si-NORAD decreased the expression of GPX4, FTH1, KEAP1, NCOA4, and Nrf2, while increasing Xct levels, confirming the involvement of ferroptosis. Our findings reveal that NORAD plays a critical role in endothelial cell proliferation, migration, and apoptosis, and its silencing induces ferroptosis. The regulatory network involving NORAD, miR-106a, and their target genes provides a potential therapeutic avenue for atherosclerosis.

Effects of vitamin D signaling in cardiovascular disease: centrality of macrophage polarization

Among the leading causes of natural death are cardiovascular diseases, cancer, and respiratory diseases. Factors causing illness include genetic predisposition, aging, stress, chronic inflammation, environmental factors, declining autophagy, and endocrine abnormalities including insufficient vitamin D levels. Inconclusive clinical outcomes of vitamin D supplements in cardiovascular diseases demonstrate the need to identify cause-effect relationships without bias. We employed a spectral clustering methodology capable of analyzing large diverse datasets for examining the role of vitamin D's genomic and non-genomic signaling in disease in this study. The results of this investigation showed the following: (1) vitamin D regulates multiple reciprocal feedback loops including p53, macrophage autophagy, nitric oxide, and redox-signaling; (2) these regulatory schemes are involved in over 2,000 diseases. Furthermore, the balance between genomic and non-genomic signaling by vitamin D affects autophagy regulation of macrophage polarization in tissue homeostasis. These findings provide a deeper understanding of how interactions between genomic and non-genomic signaling affect vitamin D pharmacology and offer opportunities for increasing the efficacy of vitamin D-centered treatment of cardiovascular disease and healthy lifespans.

Hypoxia Affects Autophagy in Human Umbilical Vein Endothelial Cells via the IRE1 Unfolded Protein Response

OBJECTIVE

The purpose of this study was to investigate the role of the unfolded protein response, specifically the inositol-requiring enzyme 1 (IRE1) signaling pathway, in hypoxia-induced autophagy in human umbilical venous endothelial cells (HUVECs).

METHODS

The expression of IRE1 and autophagy relative protein in HUVECs with hypoxia was explored by Western blotting, qRT-PCR and confocal microscopy. Further, we evaluated the biological effects of HUVECs by tube formation assay and wound healing assay in vitro. Finally, we examined the function of IRE1 in local blood vessels through animal models.

RESULTS

Hypoxia activated the IRE1 signaling pathway and induced autophagy in a time-dependent manner in HUVECs and further influenced the biological effects of HUVECs. Intraperitoneal injection of IRE1 inhibitors inhibited local vascular autophagy levels and lipid accumulation in model animals.

CONCLUSION

Hypoxia can induce autophagy and activate the IRE1 signaling pathway in HUVECs and the IRE1 signaling pathway is involved in autophagy in hypoxic conditions.

Roles of autophagy-related genes in the therapeutic effects of Xuanfei Pingchuan capsules on chronic obstructive pulmonary disease based on transcriptome sequencing analysis

Objective: Autophagy plays an important role in the occurrence and development of chronic obstructive pulmonary disease (COPD). We evaluated the effect of Xuanfei Pingchuan capsule (XFPC) on autophagy-related genes of COPD by a bioinformatics analysis and experimental verification. Methods: The best treatment duration was screened by CCK8 assays. HBE cells were divided into three groups: blank, CSE and XFPC. After intervened by XFPC, HBE cells were collected and sent to Shenzhen Huada Gene Company for transcriptome sequencing. Subsequently, differential expression analyses, target gene prediction, and function enrichment analyses were carried out. Expression changes were verified in HBE cells by real-time Quantitative PCR (RT-qPCR) and western blotting (WB). Results: The result of differential expression analysis displayed that 125 target genes of HBE cells were mainly related to mitogen-activated protein kinase (MKK) binding, interleukin 33 binding, 1-Pyrroline-5-carboxylate dehydrogenase activity, and the mitogen-activated protein kinase (MAPK) signal pathway. Among the target genes, the core genes related to autophagy obtained by maximum neighborhood component algorithm were CSF1, AREG, MAPK9, MAP3K7, and AKT3. RT-qPCR and WB methods were used to verify the result, it showed similar expression changes in CSF1, MAPK9, MAP3K7, and AKT3 in bronchial epithelial cells to those in the bioinformatics analysis. Conclusion: Through transcriptome sequencing and validation analysis, we predicted that CSF1, MAPK9, MAP3K7, and AKT3 may be the potential autophagy-related genes that play an important role in the pathogenesis of COPD. XFPC may regulate autophagy by down-regulating the expression of CSF1, MAPK9, MAP3K7, and AKT3, thus achieving the purpose of treating chronic obstructive pulmonary disease.

Apoptotic Cell Death in Bicuspid-Aortic-Valve-Associated Aortopathy

The bicuspid aortic valve (BAV) is the most common cardiovascular congenital abnormality and is frequently associated with proximal aortopathy. We analyzed the tissues of patients with bicuspid and tricuspid aortic valve (TAV) regarding the protein expression of the receptor for advanced glycation products (RAGE) and its ligands, the advanced glycation end products (AGE), as well as the S100 calcium-binding protein A6 (S100A6). Since S100A6 overexpression attenuates cardiomyocyte apoptosis, we investigated the diverse pathways of apoptosis and autophagic cell death in the human ascending aortic specimen of 57 and 49 patients with BAV and TAV morphology, respectively, to identify differences and explanations for the higher risk of patients with BAV for severe cardiovascular diseases. We found significantly increased levels of RAGE, AGE and S100A6 in the aortic tissue of bicuspid patients which may promote apoptosis via the upregulation of caspase-3 activity. Although increased caspase-3 activity was not detected in BAV patients, increased protein expression of the 48 kDa fragment of vimentin was detected. mTOR as a downstream protein of Akt was significantly higher in patients with BAV, whereas Bcl-2 was increased in patients with TAV, assuming a better protection against apoptosis. The autophagy-related proteins p62 and ERK1/2 were increased in patients with BAV, assuming that cells in bicuspid tissue are more likely to undergo apoptotic cell death leading to changes in the wall and finally to aortopathies. We provide first-hand evidence of increased apoptotic cell death in the aortic tissue of BAV patients which may thus provide an explanation for the increased risk of structural aortic wall deficiency possibly underlying aortic aneurysm formation or acute dissection.

Low shear stress induces inflammatory response via CX3CR1/NF-κB signal pathway in human umbilical vein endothelial cells

Low shear stress (LSS) has been reported to induce atherosclerosis. However, the molecular mechanisms underlying inflammation induced by LSS are still poorly understood. The objective of our study is the comprehensive identification of molecular circuitry involved in low shear stress-induced inflammation in human umbilical vein endothelial cells (HUVECs) through protein profiling and cell function experiment. In this study, Western blotting analyses revealed a significant increase in the expression of CX3CR1, nucleusP65, intercellular adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and Interleukin-6 (IL-6), while the expression of cytosolic P65 and IκB has significantly decreased in HUVECs treated with low shear stress. CX3CR1 Sh-RNA was use to reveal its effect on LSS-induced inflammation. Further, specific NF-κB P65 inhibitors pyrrolidinedithiocarbamate (PDTC) were used to reveal the downstream NF-κB P65 exclusively involved in LSS-induced inflammation in HUVECs, this effect can be abrogated by CX3CR1 sh-RNA and NF-κB inhibitors. Monocyte adhesion assay and scratch test revealed low shear stress to promotes adhesion of monocytes and migration of cells, this effect can be abrogated by CX3CR1 sh-RNA and NF-κB inhibitors. LSS was involved in the expression of adhesion molecules and chemokines, which are important for the initiation of endothelial inflammation-related atherosclerosis. Therefore, the cell signaling pathways activated by LSS in endothelial cells may represent therapeutic targets of atherosclerosis.

Cholesterol efflux regulator ABCA1 exerts protective role against high shear stress-induced injury of HBMECs via regulating PI3K/Akt/eNOS signaling

Background

In brain, microvascular endothelial cells are exposed to various forces, including shear stress (SS). However, little is known about the effects of high shear stress (HSS) on human brain microvascular endothelial cells (HBMECs) and the underlying mechanism. The cholesterol efflux regulator ATP-binding cassette subfamily A member 1 (ABCA1) has been demonstrated to exert protective effect on HBMECs. However, whether ABCA1 is involved in the mechanism underneath the effect of HSS on HBMECs remains obscure. In the present study, a series of experiments were performed to better understand the effect of HSS on cellular processes of HBMECs and the possible involvement of ABCA1 and PI3K/Akt/eNOS in the underlying mechanisms.

Results

HBMECs were subjected to physiological SS (PSS) or high SS (HSS). Cell migration was evaluated using Transwell assay. Apoptotic HBMECs were detected by flow cytometry or caspase3/7 activity. IL-1β, IL-6, MCP-1 and TNF-α levels were measured by ELISA. RT-qPCR and western blotting were used for mRNA and protein expression detection, respectively. ROS and NO levels were detected using specific detection kits. Compared to PSS, HBMECs exhibited decreased cell viability and migration and increased cell apoptosis, increased levels of inflammatory cytokines, and improved ROS and NO productions after HSS treatment. Moreover, HSS downregulated ABCA1 but upregulated the cholesterol efflux-related proteins MMP9, AQP4, and CYP46 and activated PI3K/Akt/eNOS pathway. Overexpression of ABCA1 in HBMECS inhibited PI3K/Akt/eNOS pathway and counteracted the deleterious effects of HSS. Contrary effects were observed by ABCA1 silencing. Inhibiting PI3K/Akt/eNOS pathway mimicked ABCA1 effects, suggesting that ABCA1 protects HBMECs from HSS via PI3K/Akt/eNOS signaling.

Conclusion

These results advanced our understanding on the mechanisms of HSS on HBMECs and potentiated ABCA1/PI3K/Akt/eNOS pathway as therapeutic target for cerebrovascular diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12868-022-00748-2.

Therapeutic potential of traditional Chinese medicine in atherosclerosis: A review

Atherosclerosis is the onset of endothelial cell damage and is characterized by abnormal accumulation of fibrinogen and lipid in large and middle arteries. Recent researches indicate that traditional Chinese medicine including Notoginseng Radix et Rhizoma, Astragali Radix, Salviae Miltiorrhizae Radix et Rhizoma, Ginseng Radix et Rhizoma, Fructus Crataegi, Glycyrrhizae Radix et Rhizoma, Polygoni Multiflori Radix, Fructus Lycii, and Coptidis Rhizoma have therapeutic effects on atherosclerosis. Furthermore, the pharmacological roles of these kinds of traditional Chinese medicine in atherosclerosis refer to endothelial function influences, cell proliferation and migration, platelet aggregation, thrombus formation, oxidative stress, inflammation, angiogenesis, apoptosis, autophagy, lipid metabolism, and the gut microbiome. Traditional Chinese medicine may serve as potential and effective anti-atherosclerosis drugs. However, a critical study has shown that Notoginseng Radix et Rhizoma may also have toxic effects including pustules, fever, and elevate circulating neutrophil count. Further high-quality studies are still required to determine the clinical safety and efficacy of traditional Chinese medicine and its active ingredients.

Exposure of human cerebral microvascular endothelial cells hCMEC/D3 to laminar shear stress induces vascular protective responses

Endothelial cells (ECs) are constantly submitted in vivo to hemodynamical forces derived from the blood circulation, including shear stress (SS). ECs are able to detect SS and consequently adapt their phenotype, thus affecting many endothelial functions. If a plethora of shear stress-regulated molecular networks have been described in peripheral ECs, less is known about the molecular responses of microvascular brain ECs which constitute the blood-brain barrier (BBB). In this work, we investigated the response of human cerebral microvascular ECs to laminar physiological shear stress using the well characterized hCMEC/D3 cell line. Interestingly, we showed that hCMEC/D3 cells responded to shear stress by aligning perpendicularly to the flow direction, contrary to peripheral endothelial cells which aligned in the flow direction. Whole proteomic profiles were compared between hCMEC/D3 cells cultured either in static condition or under 5 or 10 dyn.cm-2 SS for 3 days. 3592 proteins were identified and expression levels were significantly affected for 3% of them upon both SS conditions. Pathway analyses were performed which revealed that most proteins overexpressed by SS refer to the antioxidant defense, probably mediated by activation of the NRF2 transcriptional factor. Regarding down-regulated proteins, most of them participate to the pro-inflammatory response, cell motility and proliferation. These findings confirm the induction of EC quiescence by laminar physiological SS and reveal a strong protective effect of SS on hCMEC/D3 cells, suggesting a similar effect on the BBB. Our results also showed that SS did not significantly increase expression levels nor did it affect the localization of junctional proteins and did not afect either the functional activity of several ABC transporters (P-glycoprotein and MRPs). This work provides new insights on the response of microvascular brain ECs to SS and on the importance of SS for optimizing in vitro BBB models.

Microvascular system of hip joint constituents with special reference to ultrastructural findings and early arteriosclerosis

This study aimed to examine the ultrastructure of the arteries of the synovium, acetabular labrum, and ligamentum teres of the hip joint using light, scanning electron, and transmission electron microscopes to identify features of early arteriosclerosis. Tissues collected from three patients (under 40 years of age) with osteonecrosis of the femoral head were immersed in 8 N HCl at 60 °C for 20 min to digest collagen fibers for scanning electron microscopy. Tortuous arterioles and arteries were noted in the joint components, including the synovium, acetabular labrum, and ligamentum teres. The ultrastructure of the arterioles appeared normal; however, intimal thickening was found in most arteries. The thickened intima had abundant elastic fibers and many smooth muscle cells (which were of a synthetic phenotype because they had a few actin filaments and well-developed rough endoplasmic reticulum). This study illustrates that arteriosclerotic changes are present in tortuous arteries in the synovium, acetabular labrum, and ligamentum teres of the hip joint even from a relatively young age and suggests that meandering blood vessels may be the preferred foci of arteriosclerosis.

LncRNA MEG3 restrained pulmonary fibrosis induced by NiO NPs via regulating hedgehog signaling pathway-mediated autophagy

Long noncoding RNA maternally expressed gene 3 (lncRNA MEG3) was down-regulated in pulmonary fibrosis of rats induced by Nickel oxide nanoparticles (NiO NPs), while the downstream regulatory mechanisms of MEG3 remain unclear. This study aimed to investigate the relationship among MEG3, Hedgehog (Hh) signaling pathway and autophagy in pulmonary fibrosis caused by NiO NPs. The pulmonary fibrosis model in rats was constructed by intratracheal instillation of 0.015, 0.06, and 0.24 mg/kg NiO NPs twice a week for 9 weeks. Collagen deposition model was established by treating A549 cells with 25, 50, and 100 μg/mL NiO NPs for 24 h. Our results indicated that NiO NPs activated Hh pathway, down-regulated the expression of MEG3, and reduced autophagy activity in vivo and in vitro. Meanwhile, the autophagy process was promoted by Hh pathway inhibitor (CDG-0449), while the collagen formation in A549 cells was reduced by autophagy activator (Rapamycin). Furthermore, the overexpressed MEG3 inhibited the activation of Hh pathway, resulting in autophagy activity enhancement along with collagen formation reduction. In summary, lncRNA MEG3 can restrain pulmonary fibrosis induced by NiO NPs via regulating hedgehog signaling pathway-mediated autophagy, which may serve as a potential therapeutic strategy for pulmonary fibrosis.

Preoperative Morphological Prediction of Early Reoperation Risk After Primary Repair in Tetralogy of Fallot: A Contemporary Analysis of 83 Cases

This study was conducted to investigate the pulmonary artery (PA) variations in tetralogy of Fallot (TOF) and preoperative morphological predictors for early reoperation. Eighty-three TOF patients and 20 children with normal PA were included. The TOF group was divided into two subsets according to whether or not reoperation was performed within 3 years postoperatively. Clinical information was obtained, along with computed tomography (CT)-based three-dimensional geometry of the PA. Morphological measurements of the length of the main PA branches, the angles between them, and the cross-sectional area of each segment of the PAs were acquired using computer software. Logistic regression and receiver operating characteristic curves were applied to analysis. The TOF group showed a significantly smaller PA size and irregular PA shape, with lower Nakata and McGoon indices, than the control group. The median bifurcation angle (angle-γ) was greater than 100° in the TOF group, as compared to 66.70° in the control group (P < 0.000). Residual obstruction of the infundibulum or PAs was the main reason for early reoperation in this series. The development of the main PA and left PA was poorer in the reoperation subset than in the non-reoperation subset (P ≤ 0.01). The preoperative angle-γ in the reoperation subset was larger than that in the non-reoperation subset (median, 117.8° vs. 112.0°, P = 0.026). Higher weight (OR = 0.372) and McGoon index (OR = 0.122) were protective factors, while larger angle-γ (> 114.8°, OR = 5.040) and angle-γ normalized by body surface area (BSA) (γ/BSA > 297.9, OR = 18.860) were risk factors. This study provides an intuitive perspective of PA anatomical variations in TOF. Larger preoperative PA bifurcation angle and γ/BSA were morphological risk predictors of postoperative reoperation in patients with TOF.

Dendrobium catenatum Lindl. Water Extracts Attenuate Atherosclerosis

Objectives

Dendrobium catenatum Lindl. (DH) is a Chinese herbal medicine, which is often used to make tea to improve immunity in China. Rumor has it that DH has a protective effect against cardiovascular disease. However, it is not clear how DH can prevent cardiovascular disease, such as atherosclerosis (AS). Therefore, the purpose of this study is to study whether DH can prevent AS and the underlying mechanisms.

Methods

Zebrafish larvae were fed with high-cholesterol diet (HCD) to establish a zebrafish AS model. Then, we used DH water extracts (DHWE) to pretreat AS zebrafish. The plaque formation was detected by HE, EVG, and oil red O staining. Neutrophil and macrophage counts were calculated to evaluate the inflammation level. Reactive oxygen species (ROS) activity, malondialdehyde (MDA) content, and superoxide dismutase (SOD) activity in zebrafish were measured to reflect oxidative stress. The cholesterol accumulation and the levels of lipid, triglyceride (TG), and total cholesterol (TC) were measured to reflect lipid metabolism disorder. Then, parallel flow chamber was utilized to establish a low shear stress- (LSS-) induced endothelial cell (EC) dysfunction model. EA.hy926 cells were exposed to LSS (3 dyn/cm²) for 30 min and treated with DHWE. The levels of ROS, SOD, MDA, glutathione (GSH), and glutathiol (GSSG) in EA.hy926 cells were analysed to determine oxidative stress. The release of nitric oxide (NO), endothelin-1 (ET-1), and epoprostenol (PGI₂) in EA.hy926 cells was measured to reflect EC dysfunction. The mRNA expression of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in EA.hy926 cells was detected to reflect EC dysfunction inflammation.

Results

The results showed that DHWE significantly reduced cholesterol accumulation and macrophage infiltration in early AS. Finally, DHWE significantly alleviate the lipid metabolism disorder, oxidative stress, and inflammation to reduce the plaque formation of AS zebrafish larval model. Meanwhile, we also found that DHWE significantly improved LSS-induced EC dysfunction and oxidative stress in vitro.

Conclusion

Our results indicate that DHWE could be used as a prevention method to prevent AS.

Enhanced Autophagy in GAB1-Deficient Vascular Endothelial Cells Is Responsible for Atherosclerosis Progression

Autophagy is a host machinery that controls cellular health. Dysfunction of autophagy is responsible for the pathogenesis of many human diseases that include atherosclerosis obliterans (ASO). Physiologically, host autophagy removes aging organelles and delays the formation of atherosclerotic plaque. However, in ischemia event, dysregulated autophagy can be induced to trigger autosis, leading to an inevitable cellular death. Grb2-associated binder 1 (GAB1) is a docking/scaffolding adaptor protein that regulates many cell processes including autophagy. Our study first reported that the protein expression of GAB1 significantly decreased in ASO. Mechanically, our results showed that inhibition of Akt (protein kinase B), the upstream of mTOR (mechanistic target of rapamycin), significantly enhanced autophagy by demonstrating the downregulation of p62/Sequestosome 1 expression and the upregulation of the ratio of LC3II/LC3I. Conversely, we found that the inhibition of ERK1/2 (extracellular signal-regulated kinases1/2), p38, and JNK (c-Jun N-terminal kinase) signaling pathway, respectively, significantly inhibited autophagy by demonstrating the upregulation of p62 expression and the downregulation of the ratio of LC3II/LC3I. Further, we demonstrated that knockdown of GAB1 significantly increased autophagy in HUVECs (human umbilical vein endothelial cells) via activation of MAPK (mitogen-activated protein kinase) pathways that include ERK1/2, p38, and JNK. Moreover, we found that knockdown of GAB1 profoundly inhibited HUVEC proliferation, migration, and tube formation. Taken together, this study first suggests that GAB1 is a key regulator of autophagy in HUVECs. Targeting GAB1 may serve as a potential strategy for the atherosclerosis treatment.

A Novel Promising Frontier for Human Health: The Beneficial Effects of Nutraceuticals in Cardiovascular Diseases

Cardiovascular diseases (CVDs) such as hypertension, atherosclerosis, myocardial infarction, and diabetes are a significant public health problem worldwide. Although several novel pharmacological treatments to reduce the progression of CVDs have been discovered during the last 20 years, the better way to contain the onset of CVDs remains prevention. In this regard, nutraceuticals seem to own a great potential in maintaining human health, exerting important protective cardiovascular effects. In the last years, there has been increased focus on identifying natural compounds with cardiovascular health-promoting effects and also to characterize the molecular mechanisms involved. Although many review articles have focused on the individual natural compound impact on cardiovascular diseases, the aim of this manuscript was to examine the role of the most studied nutraceuticals, such as resveratrol, cocoa, quercetin, curcumin, brassica, berberine and Spirulina platensis, on different CVDs.

Laminar flow inhibits the Hippo/YAP pathway via autophagy and SIRT1-mediated deacetylation against atherosclerosis

Atherosclerosis is a multifactorial disease of the vasculature, and shear stress is a crucial regulator of its process. Disturbed flow promotes atherosclerotic effects, while laminar flow has a protective action on the endothelium. Hippo/YAP is a major cascade that senses various mechanical cues and mediates the expression of pro-inflammatory genes. However, the mechanism modulating the transcription factor YAP in response to different patterns of blood flow remains unclear. In this study, we provide evidence that shear stress modulates YAP activity via autophagy in endothelial cells. Laminar flow promoted the expression of the autophagic markers BECLIN 1 and LC3II/LC3I. Autophagy blockade using a chemical inhibitor repressed YAP degradation under laminar flow. Conversely, the induction of autophagy under disturbed flow partially antagonized the nuclear import and transcriptional activation of YAP. In parallel, laminar flow led to the increased expression of SIRT1 protein, a NAD⁺-dependent deacetylase. Further investigation showed that SIRT1-mediated YAP deacetylation. The forced expression of SIRT1 under disturbed flow effectively attenuated YAP activation and nuclear accumulation, thereby downregulating the expression of pro-inflammatory genes. In atheroprone vessels of mice receiving rapamycin to induce autophagy, the enhanced expression of SIRT1 was observed together with YAP repression. Altogether, these results show that endothelial autophagy and SIRT1 expression induced by laminar flow contribute to the inhibition of Hippo/YAP signaling and interrupt atherosclerotic plaque formation.

Inhibitory Effects of Ginsenoside Rb1 on Early Atherosclerosis in ApoE-/- Mice via Inhibition of Apoptosis and Enhancing Autophagy

Inflammation is a major contributing factor to the progression of atherosclerosis. Ginsenoside Rb1 (Rb1), an active saponin of Panax notoginseng, has been found to exert beneficial effects on inflammation and oxidative stress. This study investigated the ability of Rb1 to inhibit the formation of atherosclerotic plaques and the potential mechanisms. In this study, the effects of Rb1 on the development of atherosclerosis were investigated in ApoE-/- deficient mice fed with a western diet. Mice were intragastrically administrated with Rb1 (10 mg/kg) for 8 weeks. This study is that ginsenoside Rb1 exerted an inhibitory effect on early atherosclerosis in ApoE-/- mice via decreasing body weight and food intake daily, upregulating the lipid levels of serum plasma, including those of TC, TG and LDL-C and HDL-C and reducing the atherosclerotic plaque area, suppressing inflammatory cytokines (levels of IL-1β, IL-6 and TNF-α) in the serum of ApoE-/- mice, changing the expression levels of BCL-2, BAX, cleaved caspase-3 and cleaved caspase-9 and weakening apoptosis associated with anti-inflammatory activity. Hence, all these effects against atherosclerosis were tightly associated with regulation of necrosis or apoptosis associated with anti-inflammatory activity. Additionally, the results found that ginsenoside Rb1 increased autophagy flux to inhibit apoptosis via acceleration of autophagy by promoting transformation of LC3 from type I to type II in high-fat diet-induced atherosclerosis in ApoE-/- mice. This finding, along with those of the previous study, provides evidence that Rb1 promotes the process of autophagy to protect against atherosclerosis via regulating BCL-2 family-related apoptosis. These results indicate that Rb1 exhibits therapeutic effects in atherosclerosis by reversing the imbalance between apoptosis and autophagy.