A novel synthetic dibenzocyclooctadiene lignan analog XLYF-104-6 attenuates lipopolysaccharide-induced inflammatory response in RAW264.7 macrophage cells and protects BALB/c mice from sepsis

MicroRNA-181a-5p Regulates Inflammatory Response of Macrophages in Sepsis

The aim of this study was to evaluate the role of miR-181a-5p in sepsis, and to further explore the molecular mechanism. RAW 264.7 cells were stimulated with 1 μg/ml LPS for 4 hours. Firstly, qRT-PCR and ELISA was adopted to evaluate the expression of miR-181a-5p and p ro-inflammatory cytokines in RAW 264.7 macrophages a fter LPS stimulation. Results showed that pro-inflammatory cytokines and miR-181a-5p were significantly increased after LPS treatment. Then, we identified that sirtuin-1 (SIRT1) was a direct target of miR-181a-5p and it was down-regulated in LPS treated RAW264.7 macrophages. Furthermore, the data suggested that the miR-181a-5p inhibitor significantly inhibited LPS enhanced inflammatory cytokines expression and NF-κB pathway activation, and these changes were eliminated by SIRT1 silencing. Moreover, the role of the miR-181a-5p inhibitor on sepsis was studied in vivo. We found that the miR-181a-5p inhibitor significantly decreased the secretion of inflammatory factors, and the levels of creatine (Cr), blood urea nitrogen (BUN), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in a serum for mice with sepsis. However, all the effects were reversed by SIRT1-siRNA. In summary, these results indicated that miR-181a-5p was involved in sepsis through regulating the inflammatory response by targeting SIRT1, suggesting that miR-181a-5p may be a potential target for the treatment of sepsis.

Selenium Pretreatment Alleviated LPS-Induced Immunological Stress Via Upregulation of Several Selenoprotein Encoding Genes in Murine RAW264.7 Cells

This study was conducted to profile selenoprotein encoding genes in mouse RAW264.7 cells upon lipopolysaccharide (LPS) challenge and integrate their roles into immunological regulation in response to selenium (Se) pretreatment. LPS was used to develop immunological stress in macrophages. Cells were pretreated with different levels of Se (0, 0.5, 1.0, 1.5, 2.0 μmol Se/L) for 2 h, followed by LPS (100 ng/mL) stimulation for another 3 h. The mRNA expression of 24 selenoprotein encoding genes and 9 inflammation-related genes were investigated. The results showed that LPS (100 ng/mL) effectively induced immunological stress in RAW264.7 cells with induced inflammation cytokines, IL-6 and TNF-α, mRNA expression, and cellular secretion. LPS increased (P < 0.05) mRNA profiles of 9 inflammation-related genes in cells, while short-time Se pretreatment modestly reversed (P < 0.05) the LPS-induced upregulation of 7 genes (COX-2, ICAM-1, IL-1β, IL-6, IL-10, iNOS, and MCP-1) and further increased (P < 0.05) expression of IFN-β and TNF-α in stressed cells. Meanwhile, LPS decreased (P < 0.05) mRNA levels of 18 selenoprotein encoding genes and upregulated mRNA levels of TXNRD1 and TXNRD3 in cells. Se pretreatment recovered (P < 0.05) expression of 3 selenoprotein encoding genes (GPX1, SELENOH, and SELENOW) in a dose-dependent manner and increased (P < 0.05) expression of another 5 selenoprotein encoding genes (SELENOK, SELENOM, SELENOS, SELENOT, and TXNRD2) only at a high level (2.0 μmol Se/L). Taken together, LPS-induced immunological stress in RAW264.7 cells accompanied with the global downregulation of selenoprotein encoding genes and Se pretreatment alleviated immunological stress via upregulation of a subset of selenoprotein encoding genes.

TMC120 displayed potent cytotoxic effect on human cervical carcinoma through enhancing the polymerization of microtubules

OBJECTIVE

In the post-HAART era, the incidence of some AIDS-defining cancers declined markedly likely reflecting HAART-related improvements in immunity, whereas incidence of some cancers such as cervical cancer has not been affected. Therefore, it is valuable to find whether antiretroviral drugs or prophylactic microbicides could treat or prevent these cancers, especially the cervical cancer.

DESIGN

We screened the anti-HIV drugs, approved or in phase III clinical trials, to identify a potential anticancer drug candidate.

METHODS

We chose cervical HeLa and SiHa cancer cells and focused on studying the antitumor effects in vitro and in vivo. Cell proliferation was measured by MTT assay, the cytotoxic effect was obtained through apoptosis as evidenced by Annexin V flow cytometry assay because of the arresting of cancer cells in G2/M phase of cell cycle. Nude mice xenograft model was performed to detect the antitumor effect in vivo.

RESULTS

TMC120 was identified as a potential anticancer drug candidate. TMC120 displayed potent cytotoxic effect on various human cancer cells, including cervical carcinoma cell line HeLa and SiHa. Further mechanism study showed that TMC120 enhanced the polymerization of microtubules, which was followed by mitotic arrest, as well as abnormal mitotic spindles. TMC120 also substantially retarded the growth rate of the tumor in vivo.

CONCLUSION

TMC120 is a potential chemoprophylactic and therapeutic agent for cervical cancers in a manner similar to paclitaxel, and could be suitable for helping healthy women to prevent HIV infection and cervical cancer.

Dipeptidyl Vinyl Sulfone as a Novel Chemical Tool to Inhibit HMGB1/NLRP3-Inflammasome and Inflamma-miRs in Aβ-Mediated Microglial Inflammation

Rapid microglial activation and associated inflammatory pathways contribute to immune-defense and tissue repair in the central nervous system (CNS). However, persistent activation of these cells will ultimately result in vast production of pro-inflammatory mediators and other neurotoxic factors, which may induce neuronal damage and contribute to chronic neurodegenerative diseases, as Alzheimer's disease (AD). Therefore, small molecules with immunomodulatory effects on microglia may be considered as potential tools to counteract their proinflammatory phenotype and neuroimmune dysregulation in such disorders. Indeed, reducing amyloid-β (Aβ)-induced microglia activation is believed to be effective in treating AD. In this study, we investigated whether dipeptidyl vinyl sulfone (VS) was able to attenuate Aβ-mediated inflammatory response using a mouse microglial (N9) cell line and a solution containing a mixture of Aβ aggregates. We show that low levels of VS are able to prevent cell death while reducing microglia phagocytosis upon Aβ treatment. VS also suppressed Aβ-induced expression of inflammatory mediators in microglia, such as matrix metalloproteinase (MMP)-2 and MMP-9, as well as high-mobility group box protein-1 (HMGB1), nod-like receptor protein 3 (NLRP3)-inflammasome, and interleukin (IL)-1β. Interestingly, increased expression of the two critical inflammation-related microRNAs (miR)-155 and miR-146a in microglia upon Aβ treatment was also prevented by VS coincubation. Taken together, VS emerges as a potential new therapeutic strategy worthy of further investigation in improved cellular and animal models of AD.

A RG-II type polysaccharide purified from Aconitum coreanum alleviates lipopolysaccharide-induced inflammation by inhibiting the NF-κB signal pathway

Korean mondshood root polysaccharides (KMPS) isolated from the root of Aconitum coreanum (Lévl.) Rapaics have shown anti-inflammatory activity, which is strongly influenced by their chemical structures and chain conformations. However, the mechanisms of the anti-inflammatory effect by these polysaccharides have yet to be elucidated. A RG-II polysaccharide (KMPS-2E, Mw 84.8 kDa) was isolated from KMPS and its chemical structure was characterized by FT-IR and NMR spectroscopy, gas chromatography-mass spectrometry and high-performance liquid chromatography. The backbone of KMPS-2E consisted of units of [→6) -β-D-Galp (1→3)-β-L-Rhap-(1→4)-β-D-GalpA-(1→3)-β-D-Galp-(1→] with the side chain →5)-β-D-Arap (1→3, 5)-β-D-Arap (1→ attached to the backbone through O-4 of (1→3,4)-L-Rhap. T-β-D-Galp is attached to the backbone through O-6 of (1→3,6)-β-D-Galp residues and T-β-D-Ara is connected to the end group of each chain. The anti-inflammatory effects of KMPS-2E and the underlying mechanisms using lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and carrageenan-induced hind paw edema were investigated. KMPS-2E (50, 100 and 200 µg/mL) inhibits iNOS, TLR4, phospho-NF-κB-p65 expression, phosphor-IKK, phosphor-IκB-α expression as well as the degradation of IκB-α and the gene expression of inflammatory cytokines (TNF-α, IL-1β, iNOS and IL-6) mediated by the NF-κB signal pathways in macrophages. KMPS-2E also inhibited LPS-induced activation of NF-κB as assayed by electrophorectic mobility shift assay (EMSA) in a dose-dependent manner and it reduced NF-κB DNA binding affinity by 62.1% at 200 µg/mL. In rats, KMPS-2E (200 mg/kg) can significantly inhibit carrageenan-induced paw edema as ibuprofen (200 mg/kg) within 3 h after a single oral dose. The results indicate that KMPS-2E is a promising herb-derived drug against acute inflammation.