Mechanism of efferocytosis in atherosclerosis.

Atherosclerosis (AS) is a chronic inflammatory vascular disease that occurs in the intima of large and medium-sized arteries with the immune system's involvement. It is a common pathological basis for high morbidity and mortality of cardiovascular diseases. Abnormal proliferation of apoptotic cells and necrotic cells leads to AS plaque expansion, necrotic core formation, and rupture. In the early stage of AS, macrophages exert an efferocytosis effect to engulf and degrade apoptotic, dead, damaged, or senescent cells by efferocytosis, thus enabling the regulation of the organism. In the early stage of AS, macrophages rely on this effect to slow down the process of AS. However, in the advanced stage of AS, the efferocytosis of macrophages within the plaque is impaired, which leads to the inability of macrophages to promptly remove the apoptotic cells (ACs) from the organism promptly, causing exacerbation of AS. Moreover, upregulation of CD47 expression in AS plaques also protects ACs from phagocytosis by macrophages, resulting in a large amount of residual ACs in the plaque, further expanding the necrotic core. In this review, we discussed the molecular mechanisms involved in the process of efferocytosis and how efferocytosis is impaired and regulated during AS, hoping to provide new insights for treating AS.

Progress in Research on CNPY2 in Diseases.

Canopy FGF signaling regulator 2 (CNPY2) is a novel angiogenic growth factor. In recent years, increasing evidence highlights that CNPY2 has important functions in health and disease. Many new blood vessels need to be formed to meet the nutrient supply in the process of tumor growth. CNPY2 can participate in the development of tumors by promoting angiogenesis. CNPY2 also enhances neurite outgrowth in neurologic diseases and promotes cell proliferation and tissue repair, thereby improving cardiac function in cardiovascular diseases. Regrettably, there are few studies on CNPY2 in various diseases. At the same time, its biological function and molecular mechanism in the process and development of disease are still unclear. This paper reviews the recent studies on CNPY2 in cervical cancer, renal cell carcinoma, prostate cancer, colorectal cancer, lung cancer, gastric cancer, hepatocellular carcinoma, cerebral ischemia-reperfusion injury, spinal cord ischemia-reperfusion injury, Parkinson's disease, ischemic heart disease, myocardial ischemiareperfusion injury, myocardial infarction, heart failure, and non-alcoholic fatty liver disease. The biological function and molecular mechanism of CNPY2 in these diseases have been summarized in this paper. Many drugs that play protective roles in tumors, cardiovascular diseases, non-alcoholic fatty liver disease, and neurologic diseases by targeting CNPY2, have also been summarized in this paper. In addition, the paper also details the biological functions and roles of canopy FGF signaling regulator 1 (CNPY1), canopy FGF signaling regulator 3 (CNPY3), canopy FGF signaling regulator 4 (CNPY4), and canopy FGF signaling regulator 5 (CNPY5). The mechanism and function of CNPY2 should be continued to study in order to accelerate disease prevention in the future.

STK25: a viable therapeutic target for cancer treatments?

Serine/threonine protein kinase 25 (STK25) is a critical regulator of ectopic lipid storage, glucose and insulin homeostasis, fibrosis, and meta-inflammation. More and more studies have revealed a strong correlation between STK25 and human diseases. On the one hand, STK25 can affect glucose and fatty acid metabolism in normal cells or tumors. On the other hand, STK25 participates in autophagy, cell polarity, cell apoptosis, and cell migration by activating various signaling pathways. This article reviews the composition and function of STK25, the energy metabolism and potential drugs that may target STK25, and the research progress of STK25 in the occurrence and development of tumors, to provide a reference for the clinical treatment of tumors.

Salusins: advance in cardiovascular disease research.

Salusins are discovered in 2003 and divided into salusin-α and salusin-ß, which are bioactive peptides with hemodynamic and mitotic activity and mainly distributed in plasma, urine, endocrine glands and kidneys. A large number of studies have shown that salusins can regulate lipid metabolism, inflammatory response and vascular proliferation. Despite the profound and diverse physiological properties of salusins, the exact mechanism of their cardiovascular effects remains to be determined. The potential mechanisms of action of salusins in cardiovascular-related diseases such as atherosclerosis, hypertension, heart failure, myocardial infarction and myocarditis, and their use as biomarkers of cardiovascular disease are discussed. This review aims to provide a new strategy for the diagnosis and prevention of clinical cardiovascular diseases.

[Repair impact of vibration exercise with different frequencies on articular cartilage of rats with early knee osteoarthritis and its JNK/NF-κB, SOX9 mechanisms].

Objective: To investigate the repair effect and JNK/NF-κB,SOX9 mechanisms of vibration exercise with different frequencies on articular cartilage in rats with early knee osteoarthritis. Methods: Forty-eight adult male SD rats were randomly divided into six groups(n=8):model control group(MC),high frequency vibration group 1 (GP1,60 Hz),high frequency vibration 2 group (GP2,40 Hz),medium frequency vibration group (ZP,20 Hz),minor frequency group(DP,10 Hz)and normal control group(NC). Except for NC group,the rats in each group were made into early knee osteoarthritis model after six weeks of knee joint cavity injection of papain solution and 2% mixture l-cysteine on the 1st,4 th and 7th day. Each exercise group was subjected vibration to 40 minutes a day with amplitude of 2～5 mm and 5 days a week. Four weeks later, the articular cartilage of the lateral femoral condyle of the both back leg knee joints were detected by HE staining,serine O staining and Mankin scores for morphological observation. The expression levels of JNK,NF-κB p65 and Sox9 mRNA in articular cartilage of the medial femoral condyle were detected by RT-qPCR,and the protein expressions of JNK,NF-κB p65 and Sox9 were detected by Western blot. Results: Compared with the NC group,the Mankin score in other groups was significantly higher (P＜0.01). Compared with the MC group,the Mankin score of each vibration group was significantly lower(P＜0.05),the mRNA and protein expressions of JNK and NF-κB p65 in each vibration training group were significantly lower (P＜0.01),the expressions of Sox9 mRNA and protein in vibration training group were increased significantly (P＜0.01). Compared with the higher frequency group,the Mankin score,the mRNA and protein expressions of JNK and NF-κB p65 of lower frequency group were significantly lower (P＜0.05 or P＜0.01). But the expressions of Sox9 mRNA and protein were significantly higher (P＜ 0.05 or P＜0.01). Conclusion: Vibration exercise of different frequencies may present varying degrees of cartilage repair impact in rats with early knee osteoarthritis,and the cartilage repair by low-frequency vibration training is better than that by high-frequency vibration. This can be one of the mechanisms on controlling collagen synthesis by down-regulating JNK/NF-κB expression and increasing SOX9 activity of OA articular cartilage.

[Effect of needle knife on mTOR/Atg/ULK1/Beclin-1 axis and chondrocyte autophagy in rats with knee osteoarthritis].

OBJECTIVE: To observe the effect of needle knife on chondrocyte autophagy and expressions of autophagy-related protein and mammalian target of rapamycin (mTOR) in rats with knee osteoarthritis (KOA), and to explore the possible mechanism of needle knife for KOA. METHODS: A total of 42 SD rats were randomly divided into a normal group, a model group and a needle knife group, 14 rats in each group. Except for the normal group, the other two groups were injected with the mixture of papain and L-cysteine into the left hind knee joint to establish the KOA model. After modeling, the rats in the needle knife group were treated with needle knife at strip or nodule around the quadriceps femoris and medial and lateral collateral ligament on the affected side, once a week for 3 times (3 weeks). The changes of left knee circumference in each group were observed; the chondrocytes and ultrastructure of left knee joint were observed by HE staining and electron microscope; the mRNA and protein expressions of autophagy-related genes (Atg5, Atg12, Atg4a), Unc-51 like autophagy activated kinase 1 (ULK1), autophagy gene Beclin-1 and mTOR in left knee cartilage were detected by real-time fluorescence quantitative PCR and Western blot. RESULTS: After modeling, the left knee circumferences in the model group and the needle knife group were increased compared with those before modeling and in the normal group (P<0.05); after intervention, the left knee circumference in the needle knife group was smaller than that in the model group and after modeling (P<0.05). Compared with the normal group, the number of chondrocytes was decreased, and a few cells swelled, nuclei shrank, mitochondria swelled and autophagosomes decreased in the model group; compared with the model group, the number of chondrocytes was increased , and most cell structures returned to normal, and autophagosomes was increased. Compared with the normal group, the mRNA and protein expressions of Atg5, Atg12, Atg4a, Beclin-1 and ULK1 in the knee cartilage in the model group were decreased (P<0.05); compared with the model group, the expressions of the above indexes in the needle knife group were increased (P<0.05). Compared with the normal group, the mRNA and protein expressions of mTOR in the knee cartilage in the model group were increased (P<0.05); compared with the model group, the expressions of the above indexes in the needle knife group were decreased (P<0.05). CONCLUSION: The needle knife intervention could improve knee cartilage injury in rats with KOA, and its mechanism may be related to reducing the expression of mTOR and up-regulating the expressions of Atg5, Atg12, Atg4a, ULK1 and Beclin-1, so as to promote chondrocyte autophagy and delay the aging and degeneration of chondrocytes.

MicroRNA-182 Promotes Lipoprotein Lipase Expression and Atherogenesisby Targeting Histone Deacetylase 9 in Apolipoprotein E-Knockout Mice.

BACKGROUND: Lipoprotein lipase (LPL) expressed in macrophages plays an important role in promoting the development of atherosclerosis or atherogenesis. MicroRNA-182 (miR-182) is involved in the regulation of lipid metabolism and inflammation. However, it remains unclear how miR-182 regulates LPL and atherogenesis.Methods and Results:Using bioinformatics analyses and a dual-luciferase reporter assay, we identified histone deacetylase 9 (HDAC9) as a target gene of miR-182. Moreover, miR-182 upregulated LPL expression by directly targetingHDAC9in THP-1 macrophages. Hematoxylin-eosin (H&E), Oil Red O and Masson's trichrome staining showed that apolipoprotein E (ApoE)-knockout (KO) mice treated with miR-182 exhibited more severe atherosclerotic plaques. Treatment with miR-182 increased CD68 and LPL expression in atherosclerotic lesions in ApoE-KO mice, as indicated by double immunofluorescence staining in the aortic sinus. Increased miR-182-induced increases in LPL expression in ApoE-KO mice was confirmed by real-time quantitative polymerase chain reaction and western blotting analyses. Treatment with miR-182 also increased plasma concentrations of proinflammatory cytokines and lipids in ApoE-KO mice. CONCLUSIONS: The results of the present study suggest that miR-182 upregulates LPL expression, promotes lipid accumulation in atherosclerotic lesions, and increases proinflammatory cytokine secretion, likely through targetingHDAC9, leading to an acceleration of atherogenesis in ApoE-KO mice.

[Different sources of mesenchymal stem cells for the treatment of cartilage repair in knee joint].

As propose of organ repair stem cell therapy technology, articular cartilage cannot be repaired by itself has become one of the research hotspots, repair of articular cartilage with mesenchymal stem cells has shown obvious advantages for the treatment. The scholars have made a preliminary study on the role of mesenchymal stem cells from different sources in the repair of knee articular cartilage, and with the combination of transplantation and cartilage tissue engineering, these technologies improved the human cartilage repair effect of bone marrow, adipose, synovium, cord blood derived stem cells, which achieved good clinical curative effect. Due to the different sources, the dominant and recessive factors, each stem cell will have certain advantages and disadvantages. At present, the clinical research is still in the experimental stage, there is no definite conclusion on which kind of stem cell or technology is more suitable for human cartilage repair. This requires the validation of large-scale or combining with new processing technology clinical trials and the long-term clinical effect, it also provides for the basis for further clinical research.

Synthesis and antioxidant activity of curcumin analogs.

Numerous biological activities including antioxidant, antitumor, anti-inflammation, and antivirus of the natural product curcumin were reported. However, the clinical application of it was significantly limited by its instability, poor solubility, less body absorbing, and low bioavailability. This review focuses on the structure modification and antioxidant activity evaluation of curcumin. To study the structure-activity relationship (SAR), five series of curcumin analogs were synthesized and their antioxidant activity were evaluated in vitro. The results showed that electron-donating groups, especially the phenolic hydroxyl group are an essential component to improve the antioxidant activity.

MicroRNA-186 promotes macrophage lipid accumulation and secretion of pro-inflammatory cytokines by targeting cystathionine γ-lyase in THP-1 macrophages.

BACKGROUND AND AIMS: Several studies suggest that cardiomyocyte-enriched miR-186 is involved in cardiac injury and myocardial infarction, and also plays an important role in atherosclerotic diseases, but the underlying mechanism is unknown. Cystathionine-γ-lyase (CSE) is the predominant enzyme to produce H2S in the cardiovascular system. Here, miR-186 was identified to bind to the 3'UTR of CSE. In this study, we aimed at exploring whether miR-186 affects lipid accumulation and secretion of pro-inflammatory cytokines by targeting CSE and its underlying mechanism in human THP-1 macrophages and peripheral blood monocyte-derived macrophages (PBMDM). PBMDM just as a control group for the comparison with the THP-1 macrophages. METHODS: MiR-186 target genes, CSE 3'UTR sequence and free energy were predicted and analyzed by bioinformatics analyses and dual-luciferase reporter assays. The expression of CSE mRNA and protein were measured by real-time quantitative PCR and western blot analyses. The lipid accumulation in THP-1 macrophages was detected by high performance liquid chromatography (HPLC). The effects of miR-186 on secretion of IL-6, IL-1ß and TNF-α were examined by ELISA. Endogenous H2S was detected by spectrophotometry. Using small interfering RNA (siRNA) approach to decrease the expression of CSE protein and mRNA. RESULTS: We found that miR-186 directly inhibited CSE protein and mRNA expression through targeting CSE 3'UTR by bioinformatics analyses and dual-luciferase reporter assays. HPLC assays showed that miR-186 increased the lipid accumulation in human THP-1 macrophages. We also showed that miR-186 enhanced secretion of pro-inflammatory cytokines in human THP-1 macrophages. Using siRNA approach, we found that CSE siRNA could inhibit the miR-186 inhibitor-induced decrease in the expression of LPL protein and mRNA in human THP-1 macrophages, which was accompanied a decrease in the level of H2S. CONCLUSIONS: MicroRNA-186 promotes macrophage lipid accumulation and pro-inflammatory cytokine secretion by targeting cystathionine γ-lyase in THP-1 macrophages.

Cystathionine γ-lyase(CSE)/hydrogen sulfide system is regulated by miR-216a and influences cholesterol efflux in macrophages via the PI3K/AKT/ABCA1 pathway.

This study was designed to evaluate whether CSE/H2S system, which is regulated by miR-216a, regulated ABCA1-mediated cholesterol efflux and cholesterol contents in THP-1 macrophages-derived foam cells. Our qPCR and western blotting results showed that CSE/H2S significantly up-regulated the expression of ATP-binding cassette transporter A1 (ABCA1) mRNA and protein via PI3K/AKT pathway in foam cells derived from human THP-1 macrophages. The miR-216a directly targeted 3' untranslated region of CSE. It significantly reduced CSE and ABCA1 expression, and also decreased the phosphorylation of PI3K and AKT. Additionally, cholesterol efflux decreased, and cholesterol levels increased in THP-1 macrophage-derived foam cells in response to treatment with miR-216a. Our study demonstrates that CSE/H2S system is regulated by miR-216a, and regulates ABCA1-mediated cholesterol efflux and cholesterol levels through the PI3K/AKT pathway.

MicroRNA-590 Inhibits Lipoprotein Lipase Expression and Prevents Atherosclerosis in apoE Knockout Mice.

Recent studies have suggested that miR-590 may play critical roles in cardiovascular disease. This study was designed to determine the effects of miR-590 on lipoprotein lipase (LPL) expression and development of atherosclerosis in apolipoprotein E knockout (apoE-/-) mice and explore the potential mechanisms. En face analysis of the whole aorta revealed that miR-590 significantly decreased aortic atherosclerotic plaque size and lipid content in apoE-/- mice. Double immunofluorescence staining in cross-sections of the proximal aorta showed that miR-590 agomir reduced CD68 and LPL expression in macrophages in atherosclerotic lesions. MiR-590 agomir down-regulated LPL mRNA and protein expression as analyzed by RT-qPCR and western blotting analyses, respectively. Consistently, miR-590 decreased the expression of CD36 and scavenger receptor A1 (SRA1) mRNA and protein. High-performance liquid chromatography (HPLC)analysis confirmed that treatment with miR-590 agomir reduced lipid levels either in plasma orinabdominal cavity macrophages of apoE-/- mice. ELISA analysis showed that miR-590 agomir decreased plasma levels of pro-inflammatory cytokines, such as tumor necrosis factor-alpha (TNF-α), monocyte chemotactic protein-1 (MCP-1), interleukin-1ß (IL-1ß)and interleukin-6 (IL-6). In contrast, treatment with miR-590 antagomir prevented or reversed these effects. Taken together, these results reveal a novel mechanism of miR-590 effects, and may provide new insights into the development of strategies for attenuating lipid accumulation and pro-inflammatory cytokine secretion.

MicroRNA-590 attenuates lipid accumulation and pro-inflammatory cytokine secretion by targeting lipoprotein lipase gene in human THP-1 macrophages.

BACKGROUND: Accumulating evidence suggests that microRNA-590 (miR-590) has protective effects on cardiovascular diseases, but the mechanism is unknown. Interestingly, previous studies from our laboratory and others have shown that macrophage-derived lipoprotein lipase (LPL) might accelerate atherosclerosis by promoting lipid accumulation and inflammatory response. However, the regulation of LPL at the post-transcriptional level by microRNAs has not been fully understood. In this study, we explored whether miR-590 affects the expression of LPL and its potential subsequent effects on lipid accumulation and pro-inflammatory cytokine secretion in human THP-1 macrophages. METHODS AND RESULTS: Using bioinformatics analyses and dual-luciferase reporter assays, we found that miR-590 directly inhibited LPL protein and mRNA expression by targeting LPL 3'UTR. LPL Activity Assays showed that miR-590 reduced LPL activity in the culture media. Oil Red O staining and high-performance liquid chromatography assays showed that miR-590 had inhibitory effects on the lipid accumulation in human THP-1 macrophages. We also illustrated that miR-590 alleviated pro-inflammatory cytokine secretion in human THP-1 macrophages as measured by ELISA. With the method of small interfering RNA, we found that LPL siRNA can inhibit the miR-590 inhibitor-induced increase in lipid accumulation and secretion of pro-inflammatory cytokines in oxLDL-treated human THP-1 macrophages. CONCLUSIONS: MiR-590 attenuates lipid accumulation and pro-inflammatory cytokine secretion by targeting LPL gene in human THP-1 macrophages. Therefore, targeting miR-590 may offer a promising strategy to treat atherosclerotic cardiovascular diseases.

NO-1886 ameliorates glycogen metabolism in insulin-resistant HepG2 cells by GSK-3ß signalling.

OBJECTIVES: The aim of the study was to elucidate the possible role and mechanism of NO-1886 (ibrolipim, a lipoprotein lipase activator) in ameliorating insulin resistance induced by high palmitate. METHODS: HepG2 cells were cultured in RPMI 1640 medium and were treated with palmitate to induce insulin resistance. Free fatty acids (FFAs), glucose, glycogen, cell viability and mRNA and protein levels were analysed separately. KEY FINDINGS: We found that HepG2 cells treated with 0.5 mm palmitate for 48 h led to a significant decrease of insulin-induced glucose consumption (from 2.89 ± 0.85 mm in the control to 0.57 ± 0.44 mm in palmitate). Insulin resistance (IR) of HepG2 cells was induced by 0.5 mm palmitate for 48 h. NO-1886 stimulated glucose consumption, glycogen synthesis and FFA absorption in insulin-resistant HepG2 cells. Maximum stimulation effects were observed with 10 µm NO-1886 for 24 h. Compared with the dimethyl sulfoxide-treated group, 2.5 µm NO-1886 or higher could induce the mRNA expression of lipoprotein lipase. Meanwhile, NO-1886 increased the protein content of P-GSK-3ßser(9) and decreased the protein level of GSK-3ß in insulin-resistant HepG2 cells, but NO-1886 didn't change the protein levels of PI3-Kp85 and Akt2. CONCLUSION: Lipoprotein lipase activator NO-1886 could increase glycogen synthesis in HepG2 cells and could ameliorate the insulin resistance, which was associated with GSK-3 signalling.