Activation of the TLR1/2 pathway induces the shaping of the immune response status of peripheral blood leukocytes

Strong and Long-Lasting Antinociceptive and Anti-inflammatory Conjugate of Naturally Occurring Oleanolic Acid and Aspirin

The conjugate 8 was obtained as a result of condensation of 3-hydroxyiminooleanolic acid morfolide (7) and aspirin in dioxane. Analgesic effect of OAO-ASA (8) for the range of doses 0.3–300.0 mg/kg (p.o.) was performed in mice using a hot-plate test. Anti-inflammatory activity was assessed on carrageenan-induced paw edema in rats for the same range of doses. The conjugate OAO-ASA (8) did not significantly change locomotor activity of mice, therefore sedative properties of the compound should be excluded. The compound 8 proved a simple, proportional, dose-dependent analgesic action and expressed strong anti-inflammatory activity showing a reversed U-shaped, dose-dependent relation with its maximum at 30.0 mg/kg. After its combined administration with morphine (MF, 5.0 mg/kg, s.c.) the lowering of antinociceptive activity was found; however, the interaction with naloxone (NL, 3.0 mg/kg, s.c.) did not affect the antinociceptive effect of OAO-ASA (8), therefore its opioid mechanism of action should be rather excluded. After combined administration with acetylsalicylic acid (ASA, 300.0 mg/kg, p.o.) in hot-plate test, the examined compound 8 enhanced the antinociceptive activity in significant way. It also shows that rather the whole molecule is responsible for the antinociceptive and anti-inflammatory effect of the tested compound 8, however, it cannot be excluded that the summarizing effect is produced by ASA released from the compound 8 and the rest of triterpene derivative. The occurrence of tolerance for triterpenic derivative 8 was not observed, since the analgesic and anti-inflammatory effects after chronic administration of the conjugate OAO-ASA (8) was on the same level as after its single treatment. It seemed that the anti-inflammatory mechanism of action of OAO-ASA (8) is not simple, even its chronic administration lowered both blood concentration of IL-6 and mRNA IL-6 expression. However, the effects of the conjugate OAO-ASA (8) on TNF-α level and mRNA expression were opposite. Moreover, compound 8 did not change unequivocally mRNA TLR1, and TLR3 expression. Concluding, the obtained results regarding the antinociceptive and anti-inflammatory activity of new conjugate of oleanolic acid oxime and acetylsalicylic acid (OAO-ASA 8) are very interesting, but for explanation of its mechanism of action, more detailed studies are necessary.

Flagellin influences the expression of a variety of important cytokines and chemokines without affecting the immune status of umbilical cord mesenchymal stem cells

Multipotent differentiation ability, low expression of co‑stimulatory molecules and immunosuppressive effects render mesenchymal stem cells (MSCs) the best candidate for use in cell‑based therapy. At present, MSCs are widely used in clinical trials, which have, however, failed to demonstrate any long‑term therapeutic benefits of MSCs. Therefore, to improve the therapeutic potential of MSCs, it is important to understand the underlying mechanisms of the rapid disappearance of MSCs after transplantation. Toll‑like receptors (TLRs) have important roles in the induction of the immune response and the regulation of biological functions. The present study employed TLR5 agonist flagellin in order to assess whether the activation of the TLR5 pathway alters the immune status and influences the differentiation ability of MSCs isolated from umbilical cords (UC). Assessment of the proliferation of peripheral blood mononuclear cells co‑cultured with UCMSCs as well as their lactate dehydrogenase release indicated that flagellin stimulation failed to increase the immunogenicity of UCMSCs. Flow cytometric and histological cell differentiation analyses also confirmed that TLR5 activation neither enhanced the expression of co‑stimulatory molecules (CD80, CD86 and human leukocyte antigen‑E), nor influenced the differentiation ability of UCMSCs. However, polymerase chain reaction analysis indicated the induction of pro‑inflammatory molecules by flagellin, which suggested that the induced immune‑associated molecules may mediate biological functions of UCMSCs other than those assessed by the present study. Future studies should focus on the role of TLR5 in regulating other functions of UCMSCs.

Long noncoding RNA SPRY4-IT1 predicts poor patient prognosis and promotes tumorigenesis in gastric cancer

Gastric cancer (GC) is the second common cause of cancer-related death worldwide. Long noncoding RNAs (lncRNAs) are emerging as novel regulators in the cancer paradigm. However, investigation of lncRNAs on GC is still in its infancy. In this study, we focused on lncRNA SPRY4 intronic transcript 1 (SPRY4-IT1) and investigated its expression pattern, clinical significance, biological function, and molecular mechanism in GC. SPRY4-IT1 expression was examined, and its correlation with clinicopathological characteristics and patient prognosis was analyzed. A series of assays were performed to understand the role of SPRY4-IT1 in GC. SPRY4-IT1 expression was elevated in GC tissues and cell lines, and SPRY4-IT1 levels were highly positively correlated with tumor size, invasion depth, distant metastasis, TNM stage, and reduced overall survival (OS) and disease-free survival (DFS). A multivariate analysis showed that SPRY4-IT1 expression is an independent prognostic factor of OS and DFS in patients with GC. Additionally, the results of in vitro assays showed that the suppression of SPRY4-IT1 expression in GC cell line MKN-45 significantly reduced cell proliferation, colony formation, and cell migration/invasion. Moreover, the tumorigenic effects of SPRY4-IT1 were partially mediated by the regulation of certain cyclins and matrix metalloproteinases (MMPs)-related genes. Our data suggest that SPRY4-IT1 plays a critical role in GC tumorigenesis and may represent a novel prognostic marker and potential therapeutic target in patients with GC.

Toll-like receptor 4 agonist, lipopolysaccharide, increases the expression levels of cytokines and chemokines in human peripheral blood mononuclear cells

Toll-like receptors (TLRs) are members of the pattern recognition receptor family and are essential in the innate immune response. In total, 11 TLRs exist in humans, which are expressed in a variety of cells, including peripheral blood cells. TLR4 plays a significant role in the defense against gram-negative pathogens by recognizing the lipopolysaccharide (LPS) molecules in these bacteria. The aim of the present study was to detect the expression level variation of a number of major immune molecules in peripheral blood mononuclear cells (PBMCs) stimulated by LPS, in order to identify candidate genes involved in the biological functions mediated by TLR4. Reverse transcription quantitative polymerase chain reaction (RT-qPCR) analysis and an antibody chip were performed in the current study. The RT-qPCR results revealed a marked enhancement in the expression levels of various molecules, including cytokines, chemokines, growth factors and protein kinases. In addition, the antibody chip identified the increased secretion of crucial proinflammatory molecules in the supernatants collected from LPS-treated PBMCs. In conclusion, a large number of molecules were found to be involved in TLR4-mediated functions.