Search

Objective V-set and transmembrane domain-containing protein 1 (VSTM1) is negatively correlated with inflammation. However, its effect on atherosclerosis (AS) remains largely unexplored. In this study, we aimed to assess the effect of VSTM1 on the biological function of human peripheral blood mononuclear cells /macrophages stimulated by oxidized low-density lipoprotein (ox-LDL). Methods U937 cells were divided into three groups as follows: control group, pLenti-VSTM1 shRNA group (VSTM1 depletion), and pLenti-VSTM1 group (VSTM1 overexpression). Cellular migration, chemotaxis, apoptosis, and secretion of inflammatory factors of monocytes/macrophages stimulated by ox-LDL were studied. Results Overexpression of VSTM1 decreased the proliferation of U937 cells and induced cellular apoptosis. Depletion of VSTM1 enhanced the invasiveness and chemotaxis, increased the inflammatory response, and reduced the incidence of cell necrosis and apoptosis. Nuclear factor κ of B cells (NF-κB) was activated in VSTM1-depleted U937 cells. Conclusion VSTM1 might play an important role in the activation of monocytes/macrophages and participate in the pathogenesis of AS via regulating NF-κB activity.

BACKGROUND: Many antagonists of histamine (H1) receptor, in addition to antihistamine action, suppress allergic inflammation by inhibiting the formation and secretion of proinflammatory cytokines. The new antiallergic drug benzhydrylpiperazinyl butylmethylxanthine succinate (theoritin), which has an antihistamine activity comparable to the known second generation H1-antihistamines, surpasses them in the ability to suppress the allergic inflammatory reaction, which allows this drug to have additional anti-inflammatory properties associated with the inhibition of the formation of proinflammatory cytokines. AIM: This study aimed to determine the effect of theoritin on the induced release of proinflammatory cytokines interleukin (IL)-6, IL-8, and tumor necrosis factor (TNF)- in cell culture in comparison with the action of the inverse agonist of H1 receptor cetirizine and a known inflammation inhibitor glucocorticosteroid dexamethasone. MATERIALS AND METHODS: U937 cells differentiated toward macrophage-like cells were used. Cytotoxicity of the substances used was assessed in the methyltetrazolium test at different incubation times (up to 24 h). Cells were stimulated with lipopolysaccharide (LPS). The tested compounds (theoritin and cetirizine) were evaluated at concentrations from 0.001 to 100 M and dexamethasone at 10 M was tested when added to cells 1 h before (prophylactic effect) or 1 h after (therapeutic effect) the addition of LPS. The presence of IL-6, IL-8, and TNF in the supernatants was determined by enzyme immunoassay. RESULTS: For cetirizine and theoritin, no cytotoxic action was found in the tested concentrations and time points. Dexamethasone inhibited the formation of IL-6 and TNF to the initial level and IL-8 to 50%60%. Theoritin led to a significant concentration-dependent decrease in the LPS-induced production of IL-6, IL-8, and TNF, and at a concentration of 100 M, the effect of theoritin was comparable with that of dexamethasone at a concentration of 10 M. The prophylactic test scheme for theoritin was more effective in suppressing LPS-induced production of proinflammatory cytokines than the curative one. The described effect of theoritin on LPS-induced production of proinflammatory cytokines exceeded that of the reference drug cetirizine. CONCLUSION: In addition to its antihistaminic action, theoritin, a new antiallergic agent, inhibits LPS-induced production of proinflammatory cytokines, which may be of clinical importance in suppressing allergic inflammation.

In systemic lupus erythematosus (SLE), the clearance of apoptotic cells and microparticles (MPs) is reduced. Some MPs contain molecules that can modulate immune responses. This study aimed to evaluate the presence of miR-126 and miR-146a in plasma MPs of patients with SLE (SLE MPs) and analyse the ability of MPs to modulate some events in the promonocytic U937 cell line. Circulating MPs were isolated from plasma samples of healthy controls (HCs), patients with SLE and other autoimmune diseases (OAD). MPs were analysed for size and cell origin by flow cytometry and content of miR-126 and miR-146a by RT-qPCR. MPs were then added to U937 cell cultures to evaluate changes in cell phenotype, cytokine expression, content of miR-126 and miR-146a, and levels of IRF5. Patients with active SLE (aSLE) showed an increase in concentration of plasma MPs that positively correlated with the SLEDAI (SLE Disease Activity Index) score. CD14+ MPs were significantly more abundant in patients with SLE than HCs. SLE MPs contained decreased levels of miR-146a, but the miR-126 content in aSLE MPs was increased. The miR-126 content in SLE MPs correlated positively with the SLEDAI score. The treatment of U937 cells with MPs from HCs and patients induced reduced expression of HLA-DR, CD18 and CD119, increased frequency of IL-6+ and TNF-α+ cells, accumulation of IL-8 in culture supernatants, increased miR-126 levels and decreased miR-146a content, but no change in the expression of IRF5. These findings suggest that plasma MPs, especially SLE MPs, could modulate some biological events in U937 cells.

The synthesis, physico–chemical characterization and cytotoxicity of four copper(II) coordination complexes, i.e. [Cu(HBPA)Cl2] (1), [Cu(BHA)2] (2), [Cu(HBPA)(BHA)Cl] CH3OH (3) and [Cu(HBPA)2]Cl2·4H2O (4), are reported. HBPA is the tridentate ligand N-(2-hydroxybenzyl)-N-(2-pyridylmethyl)amine and HBHA is the benzohydroxamic acid. The reaction between the HBHA and CuCl2.2H2O has resulted in the new complex (2) and the reaction between complex (1) and HBHA has resulted in the new complex (3). X-ray diffraction studies for complex (3) indicated the effective coordination of HBHA as BHA−. Their cytotoxicity was evaluated against three human tumoral cell lines (Colo-205, NCI-H460 and U937) and PBMC (peripheral blood mononuclear cells), using the MTT cytotoxic assay. The results toward PBMC reveal that the new copper(II) complex (2) presents lower toxicity toward normal cells. Furthermore, complex (2) presents IC50 values lower than cisplatin toward NCI-H460 and the best selectivity index obtained towards NCI-H460 (SI = 2.2) and U937 cell lines (SI = 2.0), as a result of the presence of two molecules of HBHA in its structure. Complex (3) presents IC50 values lower than cisplatin toward NCI-H460, Colo-205 and comparable to cisplatin toward U937. The evaluation of the cell death type promoted by complexes (2) and (4) was investigated toward NCI-H460 revealing better results than the standard drug cisplatin, according to the Annexin V and propidium iodide (PI) labeling experiment. Based on the studies here performed, HBHA seems to be related to lower toxicity toward PBMC and HBPA is improving directly the cytotoxity.

Background The Human T-cell Lymphotropic Virus Type-1 (HTLV-1) is a blood-borne pathogen and etiological agent of Adult T-cell Leukemia/Lymphoma (ATLL) and HTLV-1 Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP). HTLV-1 has currently infected up to 10 million globally with highly endemic areas in Japan, Africa, the Caribbean and South America. We have previously shown that Extracellular Vesicles (EVs) enhance HTLV-1 transmission by promoting cell–cell contact. Results Here, we separated EVs into subpopulations using differential ultracentrifugation (DUC) at speeds of 2 k (2000×g), 10 k (10,000×g), and 100 k (100,000×g) from infected cell supernatants. Proteomic analysis revealed that EVs contain the highest viral/host protein abundance in the 2 k subpopulation (2 k > 10 k > 100 k). The 2 k and 10 k populations contained viral proteins (i.e., p19 and Tax), and autophagy proteins (i.e., LC3 and p62) suggesting presence of autophagosomes as well as core histones. Interestingly, the use of 2 k EVs in an angiogenesis assay (mesenchymal stem cells + endothelial cells) caused deterioration of vascular-like-tubules. Cells commonly associated with the neurovascular unit (i.e., astrocytes, neurons, and macrophages) in the blood–brain barrier (BBB) showed that HTLV-1 EVs may induce expression of cytokines involved in migration (i.e., IL-8; 100 k > 2 k > 10 k) from astrocytes and monocyte-derived macrophages (i.e., IL-8; 2 k > 10 k). Finally, we found that EVs were able to promote cell–cell contact and viral transmission in monocytic cell-derived dendritic cell. The EVs from both 2 k and 10 k increased HTLV-1 spread in a humanized mouse model, as evidenced by an increase in proviral DNA and RNA in the Blood, Lymph Node, and Spleen. Conclusions Altogether, these data suggest that various EV subpopulations induce cytokine expression, tissue damage, and viral spread.

Necrosis is the main mode of cell death, which leads to multiple clinical conditions affecting hundreds of millions of people worldwide. Its molecular mechanisms are poorly understood, hampering therapeutics development. Here, we identify key proteolytic activities essential for necrosis using various biochemical approaches, enzymatic assays, medicinal chemistry, and siRNA library screening. These findings provide strategies to treat and prevent necrosis, including known medicines used for other indications, siRNAs, and establish a platform for the design of new inhibitory molecules. Indeed, inhibitors of these pathways demonstrated protective activity in vitro and in vivo in animal models of traumatic brain injury, acute myocardial infarction, and drug-induced liver toxicity. Consequently, this study may pave the way for the development of novel therapies for the treatment, inhibition, or prevention of a large number of hitherto untreatable diseases.

Atherosclerosis is a progressive inflammatory disease caused by the deposition of lipids in the arterial endothelial cells. Various medications, including rosuvastatin, are recommended to treat the atherosclerosis, in other hand, Cinnamon extract has been shown to treatment atherosclerosis by modulate macrophage activation. According to these properties, we evaluate the synergistic effect of cinnamon and rosuvastatin on the formation of foam cells in the macrophages-derived from U937 cells. To investigate the toxicity of rosuvastatin and cinnamon, MTT assay was employed. The formation of foam cells was evaluated by Oil red O staining. Flow cytometry was employed to determinate CD 163 marker. RQ-PCR was used to determine the expression level of the genes which involved in cholesterol metabolism in foam cells. Data were analyzed using t-student and ANOVA tests. Our finding indicated that, the foam cells formation significantly decreased in the presence of rosuvastatin and cinnamon extraction. Expression of the CD163 on foam cell surface was also increased during exposure to these two agents. The expression level of LXR and PPARγ genes in foam cells in accompany with platelet and ox-LDL was significantly increased (p