Atherosclerosis is a chronic inflammatory disease that threatens human health and lives by causing vascular stenosis and plaque rupture. Various animal models have been employed for elucidating the pathogenesis, drug development and treatment validation studies for atherosclerosis. To the best of our knowledge, the species used for atherosclerosis research include mice, rats, hamsters, rabbits, pigs, dogs, non‑human primates and birds, among which the most commonly used ones are mice and rabbits. Notably, apolipoprotein E knockout (KO) or low‑density lipoprotein receptor KO mice have been the most widely used animal models for atherosclerosis research since the late 20th century. Although the aforementioned animal models can form atherosclerotic lesions, they cannot completely simulate those in humans with respect to lesion location, lesion composition, lipoprotein composition and physiological structure. Hence, an appropriate animal model needs to be selected according to the research purpose. Additionally, it is necessary for atherosclerosis research to include quantitative analysis results of atherosclerotic lesion size and plaque composition. Laboratory animals can provide not only experimental tissues for in vivo studies but also cells needed for in vitro experiments. The present review first summarizes the common animal models and their practical applications, followed by focus on mouse and rabbit models and elucidating the methods to quantify atherosclerotic lesions. Finally, the methods of culturing endothelial cells, macrophages and smooth muscle cells were elucidated in detail and the experiments involved in atherosclerosis research were discussed.

The present study aimed to identify potential biomarkers for atherosclerosis via analysis of gene expression profiles. The microarray dataset no. GSE20129 was downloaded from the Gene Expression Omnibus database. A total of 118 samples from the peripheral blood of female patients was used, including 47 atherosclerotic and 71 non‑atherosclerotic patients. The differentially expressed genes (DEGs) in the atherosclerosis samples were identified using the Limma package. Gene ontology term and Kyoto Encyclopedia of Genes and Genomes pathway analyses for DEGs were performed using the Database for Annotation, Visualization and Integrated Discovery tool. The recursive feature elimination (RFE) algorithm was applied for feature selection via iterative classification, and support vector machine classifier was used for the validation of prediction accuracy. A total of 430 DEGs in the atherosclerosis samples were identified, including 149 up‑ and 281 downregulated genes. Subsequently, the RFE algorithm was used to identify 11 biomarkers, whose receiver operating characteristic curves had an area under curve of 0.92, indicating that the identified 11 biomarkers were representative. The present study indicated that APH1B, JAM3, FBLN2, CSAD and PSTPIP2 may have important roles in the progression of atherosclerosis in females and may be potential biomarkers for early diagnosis and prognosis as well as treatment targets for this disease.

Previous studies have demonstrated that regulatory T cells (Tregs) are pivotal in the regulation of T cell‑mediated immune responses in atherosclerosis, a chronic autoimmune‑like disease. In the authors' previous studies, it was demonstrated that amygdalin ameliorated atherosclerosis by the regulation of Tregs in apolipoprotein E‑deficient (ApoE‑/‑) mice. Therefore, the aim of the present study was to investigate the therapeutic effect of amygdalin on low‑density lipoprotein (LDL) receptor deficient (LDLR‑/‑) mice, and to examine its immune regulatory function by the stimulation of Tregs. To establish an atherosclerosis mouse model, the LDLR‑/‑ mice were fed a high fat and high cholesterol diet then the total plasma cholesterol, triglyceride, LDL and chemokines levels were measured by an ELISA. Following sacrificing the mice, the upper sections of the aorta were stained by hematoxylin and eosin, and Oil red O to assess the plaque area. Then western blotting and reverse transcription polymerase chain reactions were performed to analysis the expression levels of cluster of differentiation 68, monocyte chemoattractant protein‑1, matrix metalloproteinase (MMP)‑2, MMP‑9 and forkhead box P3 (Foxp3). To further confirm the activation of FOXP3 by amygdalin, lentiviruses carrying Foxp3 shRNA were injected into the mice, and the serum cytokines levels were measured by ELISA. Following feeding of the mice with a high‑fat/high‑cholesterol diet, the LDLR‑/‑ mice demonstrated comparatively higher levels of triglyceride, total cholesterol and LDL, compared with levels in the amygdalin‑treated mice. By comparing the vessel area, lumen area, plaque area, and percentage aortic plaque coverage, the effects of amygdalin on pre‑existing lesions were assessed. In addition, the levels of CD68, monocyte chemoattractant protein‑1, MMP‑2 and MMP‑9 were analyzed, and analysis of the expression of interleukin (IL)‑1β, IL‑6 and tumor necrosis factor (TNF)‑α indicated that the mice treated with amygdalin had decreased expression of pro‑inflammatory cytokines. The mRNA and protein levels of Foxp3 were also quantified, and the mice treated with amygdalin demonstrated an increased number of Tregs. The knockdown of Foxp3mRNA resulted in the increased secretion of IL‑1β, IL‑6 and TNF‑α. Therefore, the data indicated that amygdalin regulated the formation of atherosclerosis and stabilized the plaque by suppressing inflammatory responses and promoting the immune‑modulation function of Tregs. Taken together, the results demonstrated the therapeutic effect of amygdalin on atherosclerosis.

Transforming growth factor (TGF)‑β1 is reported to be associated with the occurrence of atherosclerosis, although the mechanism remains unclear. Therefore, the present study aimed to investigate the involvement of TGF‑β1 signaling in atherosclerosis. A total of 56 patients with atherosclerosis and 44 healthy volunteers were involved in this study. Serum expression of TGF‑β1 and long non‑coding RNA‑ATB was detected by ELISA and quantitative polymerase chain reaction (qPCR). Receiver operating characteristic curve analysis was performed to analyze the diagnostic value of serum TGF‑β1 and lncRNA‑ATB for atherosclerosis. A human umbilical vein endothelial cell (HUVEC) line overexpressing lncRNA‑ATB was constructed. The effects of TGF‑β1 treatment and lncRNA‑ATB overexpression on HUVEC cell proliferation and viability was detected with Cell Counting Kit‑8 and MTT assays, respectively. Expression of TGF‑β1 and pro‑apoptotic Caspase‑3 in lncRNA‑ATB‑overexpressing HUVECs was detected by western blotting. In addition, the expression of lncRNA‑ATB in TGF‑β1‑treated HUVECs was detected by qPCR. It was demonstrated that serum TGF‑β1 and lncRNA‑ATB expression was significantly higher in atherosclerosis patients, compared with controls, and could be used to effectively distinguish patients from healthy individuals. TGF‑β1 treatment and lncRNA‑ATB overexpression reduced HUVEC viability and proliferation. TGF‑β1 treatment increased the expression of lncRNA‑ATB in HUVECs, while lncRNA‑ATB overexpression had no significant effect on TGF‑β1 expression. LncRNA‑ATB silencing with small interfering RNA significantly reduced the effects of TGF‑β1 treatment on the proliferation and viability of HUVECs. Furthermore, LncRNA‑ATB overexpression upregulated the expression of caspase‑3 in HUVECs. Therefore, it was concluded that TGF‑β1 may have upregulated the expression of lncRNA‑ATB to promote atherosclerosis, and lncRNA‑ATB may serve as a potential therapeutic target for atherosclerosis. However, the mechanism remains to be further investigated.

The formation of atherosclerosis is recognized to be caused by multiple factors including pathogenesis in monocytes during inflammation. The current study provided evidence that monocytic junctions were significantly altered in patients with atherosclerosis, which suggested an association between cell junctions and atherosclerosis. Claudin‑1, occludin‑1 and ZO‑1 were significantly enhanced in atherosclerosis, indicating that the tight junction pathway was activated during the pathogenesis of atherosclerosis. In addition, the gene expression of 5 connexin members involved in the gap junction pathway were quantified, indicating that connexin 43 and 46 were significantly up‑regulated in atherosclerosis. Furthermore, inflammatory factors including endoglin and SMAD were observed, suggesting that immune regulative factors were down‑regulated in this pathway. Silicon‑based analysis additionally identified that connexins and tight junctions were altered in association with monocytic inflammation regulations, endoglin pathway. The results imply that reduced expression of the immune regulation pathway in monocytes is correlated with the generation of gap junctions and tight junctions which serve important roles in atherosclerosis.

Fibroblast growth factor‑21 (FGF‑21) is a pleiotropic protein predominantly secreted in the liver, adipose tissue and pancreas. It has been reported that the metabolic hormone effects of FGF‑21 on energy metabolism are essential for human vascular endothelial cells. The aim of the present study was to investigate the therapeutic effects and the underlying primary mechanism of FGF‑21 on atherosclerosis in a rat model induced by vitamin D3 and a high fat diet. The rats with atherosclerosis were randomly divided into vehicle (PBS; negative control), FGF‑21 (6 mg/kg/d) and atorvastatin (6 mg/kg/d; positive control) groups (n=40 in each group). The rats with atherosclerosis received continuous drug or PBS administration via intravenous injection for a treatment period of 30 days, following which all animals were sacrificed. The expression levels of FGF‑21 were determined prior to and following treatment with the drug or PBS. Alterations in ultrastructure and histopathology in vascular endothelial cells were examined, and the expression of nuclear transcription factor kappa B (NF‑κB) and levels of blood lipids in the thoracic aorta tissues were also determined. The results showed that typical atheromatous plaques formed, and the mRNA and protein expression levels of FGF‑21 were lower in the vascular endothelial cells of the rats with atherosclerosis, compared with the normal rats. FGF‑21 significantly reduced blood lipids and glucose in the rats with atherosclerosis, compared with those in the PBS and atorvastatin groups (P<0.01). The expression levels of Rho kinase and NF‑κB were significantly lower in the FGF‑21 group, compared with the normal control group (P<0.01). Statistically significant differences were found in atheromatous plaques and inflammatory factors in the FGF‑21 group, compared with the PBS and atorvastatin groups (P<0.01). In conclusion, FGF‑21 significantly downregulated the levels of blood lipids, Rho kinase and NF‑κB, which contributed to atherosclerosis therapy in the model rats and indicated the potential mechanisms against atherosclerosis in the model rats.

Dendritic cells (DCs) are specialized antigen‑presenting cells which are important in immune diseases, in particular atherosclerosis, a chronic inflammatory disease, however their role in atherosclerosis‑associated immunity is unclear. To evaluate the role of DCs in atherosclerosis, exogenous bone marrow‑derived DCs were transferred into ApoE‑/‑ mice in the present study. The extent of disease was measured in the aorta and was compared with mice treated with phosphate‑buffered saline (PBS) or left untreated and fed a western diet. Mice receiving exogenous DCs demonstrated significantly larger atherosclerotic lesions compared with the mice treated with PBS, with increasing numbers of mature DCs in circulation and enhanced DC infiltration into plaque lesions, in addition to activation of circulating inflammatory components and atherosclerotic lesions. Furthermore, it was demonstrated that exogenous DCs upregulated the expression of Toll‑like receptor 4 (TLR4) on DCs, which may be an important mechanism to activate DCs and aggravate atherosclerosis. Therefore the present study concluded that exogenous DCs may induce maturation of endogenous DCs via upregulation of TLR4, further increasing the inflammatory response and accelerating atherosclerosis.

Hyperlipidemia is a major risk of atherosclerosis; however, systemic inflammatory diseases such as rheumatoid arthritis, psoriasis, systemic lupus erythematosus and systemic sclerosis are also known risks for the development of atherosclerosis. Periodontitis, a local and systemic inflammatory condition, has also been reported as a risk for atherosclerosis, but the specific link between periodontitis and atherosclerosis remains somewhat controversial. We previously reported that ligature‑induced periodontitis exacerbates atherosclerosis in hyperlipidemic Apolipoprotein E‑deficient (ApoE‑/‑) mice. To understand whether hyperlipidemia is necessary for the development and exacerbation of atherosclerosis associated with periodontitis, the present study created ligature‑induced periodontitis in both wild‑type (WT) and ApoE‑/‑ mice. Subsequently, the status of local, systemic and vascular inflammation, serum lipid contents and arterial lipid deposition were examined with histological analysis, µCT, en face analysis, serum lipid and cytokine measurements, reverse transcription‑quantitative PCR and immunohistochemical analysis. Ligature placement induced severe periodontitis in both WT and ApoE‑/‑ mice at the local level as demonstrated by gingival inflammation, alveolar bone loss, increased osteoclastic activities and inflammation in alveolar bone. Systemic inflammation was also induced by ligature placement in both WT and ApoE‑/‑ mice, albeit more so in ApoE‑/‑ mice. The serum cholesterol levels were not altered by the ligature in both WT and ApoE‑/‑ mice. However, the vascular inflammation and arterial lipid deposition were induced by ligature‑induced periodontitis only in ApoE‑/‑ mice, but not in WT mice. The present study indicated that the coupling of systemic inflammation and hyperlipidemia was necessary for the development and exacerbation of atherosclerosis induced by ligature‑induced periodontitis in mice.

The contractile to synthetic phenotypic switching of vascular smooth muscle cells (VSMCs) in response to fibroblast growth factor (FGF) has been previously described. However, the role of the inflammatory response induced by FGF signaling in VSMCs and its occurrence in atherosclerosis remains unclear. In the present study, FGF signaling promoted a contractile to secretory phenotypic transition in VSMCs. VSMCs (primary human aortic smooth muscle cells) treated with FGF exhibited a decrease in the protein expression levels of factors involved in contractility and the secretion of various chemokines was increased, as assessed by reverse transcription‑quantitative PCR and ELISA. Additionally, inhibition of FGF signaling by silencing FGF receptor substrate 2 (FRS2) decreased the protein expression levels of various chemokines. Furthermore, VSMCs in the medial layers of arteries from apolipoprotein E‑deficient mice and human atherosclerotic samples exhibited an increase in FGF signaling that was identified to be associated with an increase in the protein expression levels of pro‑inflammatory molecules, including C‑C motif chemokine ligand 2, C‑X‑C motif chemokine ligand (CXCL) 9, CXCL10 and CXCL11, compared with wild‑type mice and healthy control samples, respectively. The present results suggested that FGF signaling induced dedifferentiation of contractile VSMCs and the transition to a secretory phenotype, which may be involved in the progression of atherosclerosis. Collectively, the present results suggested that the FGF signaling pathway may represent a novel target for the treatment of atherosclerosis.

The present study aimed to investigate protein expression levels of intra‑ and extracranial atherosclerosis in rabbits following administration of a high‑fat diet. Rabbits were randomly divided into control (group A; n=9) and high‑fat diet (group B; n=9) groups. At week 12, tissues were sectioned from the common carotid artery (CCA) and middle cerebral artery (MCA). Pathological analysis was performed. Differential protein expression levels were examined by 2‑D gel electrophoresis (2‑DE) and mass spectrometry (MS) analysis and validated by western blotting. Serum lipid levels, the intima‑media thickness (IMT) and degree of atherosclerosis of the CCA and MCA were increased at week 12 in the high‑fat diet group compared with rabbits that received a normal diet. 2‑DE and MS analysis of the protein extracted from CCA and MCA detected >439 different proteins; the expression of 25 proteins was altered, and 8 proteins [albumin A chain, tropomyosin α‑1 chain (TPM1), heat shock protein 70 (HSP70), α‑smooth muscle actin, β‑galactose binding agglutinin, TPM4 isoform 2, cell keratin 9, single octylic acid glyceride β‑2) demonstrated significant alterations in expression levels. Due to limited antibody sources, only three differentially expressed proteins (TPM1, HSP70 and α‑smooth muscle actin) were examined by western blotting. The results of our previous study demonstrated that hyperlipidemia affected the IMT of intracranial and extracranial cerebral arteries. In the present study, protein expression levels of TPM1 and α‑smooth muscle actin from extracranial cerebral arteries were significantly increased compared with intracranial cerebral arteries; however, protein expression levels of HSP70 from intracranial cerebral arteries was increased compared with extracranial cerebral arteries. The differences may be closely associated with cell proliferation and metastasis, and oxidoreduction, in intra‑ and extracranial cerebral atherosclerosis. HSP70 may have protective properties against atherosclerosis via underlying anti‑inflammatory mechanisms, furthermore, differential protein expression levels (TPM1, HSP70 and α‑smooth muscle actin) between intra‑ and extracranial cerebral arteries may facilitate the identification of novel biological markers for the diagnosis and treatment of cerebral arteriosclerosis.

The transplantation of mesenchymal stem cells (MSCs) has been a reported method for alleviating atherosclerosis (AS). Because the availability of bone marrow‑derived MSCs (BM‑MSCs) is limited, the authors used this study to explore the use of a new type of MSC, human induced pluripotent stem cell‑derived MSCs (iPSC‑MSCs), to evaluate whether these cells could alleviate AS. iPSC‑MSCs were intravenously administered to ApoE knock out mice fed on a high‑fat diet (HFD) for 12 weeks. It was reported that systematically administering iPSC‑MSCs clearly reduced the size of plaques. In addition, the numbers of macrophages and lipids in plaques were lower in the HFD + iPSC‑MSCs group than in the HFD group. Furthermore, iPSC‑MSCs attenuated AS‑associated inflammation by decreasing the levels of inflammatory cytokines, such as tumor necrosis factor‑α and interleukin‑6, in serum. In addition, the expression of Notch1 was higher in the HFD group, and injecting iPSC‑MSCs reversed this effect. In conclusion, the current study provides the first evidence indicating that iPSC‑MSCs may be a new optional MSC‑based strategy for treating AS.

Atherosclerosis‑induced cardiovascular diseases (CVDs) are accompanied by substantial morbidity and mortality. The loss and injury of endothelial cells is the primary cause of atherosclerosis. Rosuvastatin is an alternative agent used to reduce the risk of cardiovascular disease. Subsequently, the present study aimed to investigate the protective effects of rosuvastatin on oxidized‑low‑density lipoprotein (ox‑LDL)‑induced human umbilical vein endothelial cell (HUVEC) injury. The viability of ox‑LDL‑cultured HUVECs with or without rosuvastatin (0.01, 0.1 and 1 µmol/l) pretreatment, and pretreatment at different time points (3, 6, 12 and 24 h) was determined using an MTT assay. Morphological changes and the extent of apoptosis were detected; the anti‑oxidase activity, including superoxide dismutase (SOD) and catalase (CAT), was examined, and the contents of malondiahdehyde (MDA) and nitric oxide (NO) were measured. The phosphorylation levels of endothelial nitric oxide synthase (eNOS), protein kinase B (Akt) and phosphoinositide 3 kinase (PI3K) were detected using western blot analysis. The results demonstrated that pretreatment with 0.01‑1 µmol/l rosuvastatin decreased cell apoptosis caused by ox‑LDL. Notably, pretreatment with 1 µmol/l rosuvastatin for >12 h increased cell viability. Additionally, DAPI staining revealed that rosuvastatin inhibited HUVEC apoptosis. Rosuvastatin treatment also resulted in increased SOD and CAT activities and decreased MDA content in ox‑LDL‑stimulated HUVECs. Furthermore, pretreatment with 0.01‑1 µmol/l rosuvastatin significantly increased` the NO content compared with HUVECs treated with ox‑LDL alone. Western blot analyses demonstrated that rosuvastatin upregulated the phosphorylation of eNOS, Akt and PI3K. These findings indicated that rosuvastatin could protect HUVECs against ox‑LDL‑induced injury through its anti‑oxidant effect and its ability to upregulate the expression of vascular endotheliocyte‑protecting factors.

The present study aimed to determine the effects of Tianxiangdan Granule on nuclear factor (NF)-κB p65 and p38 mitogen‑activated protein kinase (MAPK) inflammatory signaling pathways, and explored the possible mechanism underlying the effects of Tianxiangdan Granule on prevention and treatment of atherosclerosis. A total of 48 apolipoprotein E‑/‑ mice (age, 8 weeks) were selected and divided into two groups: The normal control group (n=12) and the modeling group (n=36). In the modeling group, mice were fed a high‑fat diet and were maintained in an artificial climate box, in order to stimulate the climate and eating habit characteristics of Xinjiang. Every morning, ApoE‑/‑ mice in the modeling group were placed in the artificial climate box at 10:00 am and were taken out at 09:00 pm and placed back in the room temperature environment. The temperature of the artificial climate box was set at 6±2˚C, relative humidity was controlled at 25‑32.8% and the light‑dark cycle was 12 h/day. The purpose of this method was to establish the Huizhuo Tanzu type atherosclerosis model. Following successful generation of the model, mice in the modeling group were randomly divided into three groups: Model group (n=10), Tianxiangdan group (n=10) and atorvastatin group (n=10). After 12 weeks, mice were sacrificed and the serum levels of interleukin (IL)‑1β and tumor necrosis factor (TNF)‑α in each group were detected. Furthermore, the expression levels of NF‑κB p65 and p38 MAPK in aortic tissue were detected. The results indicated that the concentrations of IL‑1β and TNF‑α were significantly higher in mice in the model group compared with in the normal control group (P<0.01), whereas the concentrations of IL‑1β and TNF‑α were lower in the Tianxiangdan and atorvastatin groups compared with in the model group (P<0.01). Furthermore, the protein expression levels of phosphorylated (p)‑NF‑κB p65 and p‑p38 MAPK protein were higher in aortic tissues from the model group compared with in the normal control group (P<0.01), p‑NF‑κB p65 and p‑p38 MAPK protein expression was reduced in the atorvastatin and Tianxiangdan groups compared with in the model group. The present study indicated that the mechanism underlying the effects of Tianxiangdan Granule on the prevention and treatment of atherosclerosis may be as follows: Tianxiangdan Granule may decrease the expression of the inflammatory cytokines IL‑1β and TNF‑α, and suppress activation of the NF‑κB p65 and p38 MAPK signaling pathways.

Hepatic steatosis, an indicator of atherosclerosis (AS), is always accompanied by inflammatory responses and disturbances in lipid metabolism. The present study investigated the protective effect of urantide, a urotensin II (UII) receptor antagonist, on the liver of rats with AS with hepatic steatosis by regulating the MAPK pathway. AS was induced in rats via an intraperitoneal injection of vitamin D3 and the administration of a high‑fat diet. Urantide treatment was then administered to the rats. Pathology, liver index, lipid levels and liver function were measured to determine liver injury. The expression levels of UII and G protein‑coupled receptor 14 (GPR14) were determined using immunohistochemistry, reverse transcription‑quantitative PCR and western blotting. The expression levels of MAPK‑related proteins in hepatocytes from each group were quantified using western blotting and immunofluorescence staining. Rats with AS had typical pathological changes associated with AS and hepatic steatosis, which were significantly improved by urantide treatment. Blood lipid levels, body weight, liver index and liver function were recovered in rats with AS after urantide treatment. Urantide downregulated the expression levels of UII and GPR14 in the livers of rats with AS; concurrently, the phosphorylation of Erk1/2 and JNK was significantly decreased. Moreover, no significant changes were observed in the phosphorylation of p38 MAPK in AS rat livers. In conclusion, urantide inhibits the activation of Erk1/2 and JNK by blocking the binding of UII and GPR14, thereby alleviating hepatic steatosis in rats with AS, ultimately restoring lipid metabolism in the liver and alleviating AS lesions.

Aberrant proliferation and apoptosis of vascular smooth muscle cells (VSMCs) serve a dominant role in the pathogenesis of atherosclerosis (AS). Long non‑coding (lnc)RNA H19 is reported to accelerate the progression of AS by inhibiting the apoptosis of VSMCs, whereas p53 is identified as promoting VSMC apoptosis. The present study aimed to explore the effects of H19/p53 on the pathogenesis of AS. Apolipoprotein E knockout (ApoE‑/‑) mice fed a high‑fat diet were used as in vivo AS models. Reverse transcription‑quantitative PCR and western blot were used to detect mRNA and protein expression levels, respectively. VSMC proliferation and apoptosis were respectively assessed by CCK‑8 and flow cytometry. Compared with the control group, mouse weight and plaque area were all increased in the AS model group, as was the expression of H19. Knockdown of H19 reduced the proliferation and induced apoptosis of VSMCs, and increased the expression of p53, cleaved caspase3 (c‑caspase3) and p53 upregulated modulator of apoptosis, as well as enhancing the interaction between Bax and p53 proteins. Downregulation of H19 reduced the plaque area and promoted the expression of c‑caspase3 in mouse aortic tissues in vivo, as well as enhancing the effects of simvastatin, a drug used for AS treatment. Results from the present study indicated that knockdown of H19 may prevent AS deterioration through increased p53‑mediated VSMC apoptosis.

Atherosclerosis is a chronic inflammatory disease, and it is a global clinical problem. The development of new and effective therapeutic targets for atherosclerosis is necessary. A number of microRNAs (miRNAs) have been demonstrated to serve a crucial role in atherosclerosis. However, the role of miRNA (miR)‑217 in atherosclerosis remains unclear. Therefore, the aim of the present study was to investigate the role and mechanism of miR‑217 in atherosclerosis. The level of miR‑217 was detected in the blood of patients with atherosclerosis using reverse transcription‑quantitative PCR. THP‑1 acute monocytic leukemia cells were treated with oxidized low‑density lipoprotein (ox‑LDL) to develop an atherosclerotic cell model of macrophages. The relationship between miR‑217 and sirtuin 1 (SIRT1) was determined by TargetScan and dual luciferase reporter assay. Cell apoptosis was measured by flow cytometry. Production of pro‑inflammatory factors and triglyceride (TG) and total cholesterol (TC) levels were also determined. The results demonstrated that miR‑217 was significantly upregulated in atherosclerosis. SIRT1 was demonstrated to be a direct target of miR‑217 and was downregulated in atherosclerosis. Downregulation of miR‑217 significantly inhibited ox‑LDL‑induced TG and TC level increase, cell apoptosis and the upregulation of the pro‑inflammatory factors tumor necrosis factor α, interleukin (IL)‑6 and IL‑1β. Additionally, the SIRT1/AMP‑activated protein kinase α/NF‑κB pathway was at least partially involved in modulating the effects of miR‑217 inhibition on THP‑1 cells treated with ox‑LDL. In addition, the effects of miR‑217 downregulation on ox‑LDL‑treated THP‑1 cells were eliminated by SIRT1 silencing. In conclusion, the results of the present study indicated that miR‑217 downregulation may relieve atherosclerosis through the inhibition of macrophage apoptosis and inflammatory response by targeting SIRT1.

Visceral adipose tissue-derived serine protease inhibitor (vaspin) is a novel adipokine with potential insulin-sensitizing properties, which was initially detected in the visceral adipose tissue of genetically obese rats. Previous studies have demonstrated that vaspin exerts a protective effect on arteries undergoing atherosclerosis in vitro, and it has been shown to exert anti-inflammatory and antimigratory effects on vascular smooth muscle cells. Vaspin promotes proliferation and inhibits apoptosis in endothelial cells, and decreases proliferation of the arterial intima under diabetic conditions. In addition, macrophage apoptosis is an important characteristic of atherosclerotic plaque development. In vivo experiments were performed by histological analysis, including Oil Red O, hematoxylin and eosin and Masson's trichrome staining. Mice were injected with lentivirus via the tail vein and tissues were obtained for histological analysis. Cell apoptosis was determined by flow cytometry of Annexin-V/propidium iodide dual staining and terminal deoxynucleotidyl transferase deoxyuridine triphosphate nick end labeling assay. Total proteins were extracted and protein expression levels were detected by western blot analysis. The present study aimed to investigate whether vaspin was able to protect against atherosclerotic development in vivo, and to explore the underlying mechanisms of the potential antiatherogenic effects. The results of the current study indicated that vaspin inhibited the progression of atherosclerotic plaques in apoE(‑/‑) mice by inhibiting endoplasmic reticulum stress-induced macrophage apoptosis.

Atherosclerosis is a leading cause of mortality worldwide. Artery tertiary lymphoid organ (ATLO) neogenesis is affected by abdominal aorta atherosclerosis, which may lead to an immune response. The present study obtained microarray data to investigate the gene expression differences underlying the potential pathogenesis of atherosclerosis and to elucidate the mechanisms underlying ATLO development. Microarray studies of the aorta, plaques, adventitia, blood, spleen, renal lymph nodes and ATLO were downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) were identified in aorta clusters and ATLO clusters. Kyoto Encyclopedia of Genes and Genomes enrichment and Gene Ontology (GO) analyses were conducted to predict the biological functions of DEGs. The results demonstrated that interleukin 7 receptor (Il7r), C‑X‑C motif chemokine ligand (Cxcl)16, Cxcl13, Cxcl12, C‑C motif chemokine receptor 2, C‑C motif chemokine ligand (Ccl)8, Ccl5 and Ccl12 may function through pathways associated with 'cytokine‑cytokine receptor interaction' and 'chemokine signaling pathway' in ATLO. Gene expression alterations were validated by reverse transcription‑quantitative polymerase chain reaction. Il7r appeared to be the central gene involved in these events, and chemokines and/or chemokine receptors were visualized by GO enrichment. A protein‑protein interaction network was constructed, which suggested that Il7r had a core function in all clusters. Taken together, the results indicated that Il7r upregulation may serve an important role in ATLO development via 'cytokine‑cytokine receptor interaction' and 'chemokine signaling pathway'. This may provide novel perspectives for understanding ATLO development and the regulation of the immune response in atherosclerosis.

The present study aimed to investigate the effects of saikosaponin on oxidized low‑density lipoprotein (ox‑LDL)‑induced human umbilical vein endothelial cell (HUVEC) injury and apoptosis, and examine the involvement of the mitogen‑activated protein kinase (MAPK) signaling pathway. The viability and apoptosis of HUVECs were detected using an MTT assay and flow cytometry. ELISA analysis was applied to measure the levels of tumor necrosis factor (TNF)‑α and interleukin (IL)‑6 cytokines. Nuclear factor (NF)‑κB p65 nuclear translocation was observed using immunofluorescence staining. The levels of intercellular adhesion molecule 1 and vascular cell adhesion molecule‑1 were detected using reverse transcription‑polymerase chain reaction analysis. The phosphorylation of B‑cell lymphoma 2 (Bcl‑2), Bcl‑2‑associated X protein (Bax), caspase‑3 p38, c‑Jun N‑terminal kinase (JNK) and extracellular signal‑regulated kinase (ERK)1/2 were detected using western blot analysis. The results revealed that saikosaponin increased the viability of the HUVECs and decreased the early‑stage apoptotic rate of the HUVECs induced by ox‑LDL. The expression levels of inflammatory cytokines in the injured vascular endothelial cells were decreased, the expression levels of adhesion molecules were reduced, the activity of superoxide dismutase was increased, and malondialdehyde content was decreased. Therefore, the inflammatory response and oxidative stress were inhibited. Simultaneously, the levels of Bcl‑2 increased, the levels of Bax and caspase‑3 decreased, and the nuclear translocation of NF‑κB p65 was significantly inhibited. The protein levels of phosphorylated p38 and JNK were reduced, whereas that of ERK1/2 remained unaffected. It was concluded that the MAPK signaling pathway mediated HUVEC injury induced by ox‑LDL. However, saikosaponin inhibited the HUVEC injury induced by ox‑LDL through inhibiting the ERK1/2 and p38 MAPK signaling pathways, and possibly also through the JNK and p38 MAPK signaling pathway.

Aging is the major risk factor for diseases of the cardiovascular system, such as coronary atherosclerotic heart disease, but little is known about the relationship between atherosclerosis (AS) and age‑related declines in vascular structure and function. Here, we used histological analyses in combination with molecular biology techniques to show that lipid deposition in endothelial cell was accompanied by aging and growth arrest. Endothelial cell senescence is sufficient to cause AS; however, we found that salidroside reduced intracellular lipid deposition, slowed the progression of endothelial cell senescence and inhibited the expression of the senescence‑related molecules and phosphorylated the retinoblastoma (Rb) protein. Further study confirmed that salidroside increased the percent of S phase cells in oxidized low‑density lipoprotein (ox‑LDL)‑treated endothelial cells. Collectively, vascular endothelial cell function declined with age and AS, and our data suggested that salidroside prevented ox‑LDL‑treated endothelial cell senescence by promoting cell cycle progression from G0/G1 phase to S phase via Rb phosphorylation. We demonstrated for the first time the complex interactions between AS and endothelial cell senescence, and we believe that salidroside represents a promising therapy for senescence‑related AS.