Cerium oxide nanozyme attenuates periodontal bone destruction by inhibiting ROS-NFκB pathway

Periodontitis, an inflammatory disease of oxidative stress, occurs due to the excess reactive oxygen species (ROS) contributing to cell and tissue damage that in turn leads to alveolar bone resorption...

Oxidized LDL Mediated Upregulation of ADAMTS-4 in Monocytes/Macrophages Involves The ROS-NFκB Pathway

ADAMTS-4 is a protease enzyme which involves in vascular remodeling and atherosclerosis. It was found to be upregulated in macrophages seen in atherosclerotic lesions. The aim of this study was to investigate the expression and regulation of ADAMTS-4 in oxLDL induced human monocytes/macrophages system. PBMCs isolated from human blood(hPBMCs), treated with oxLDL (50μg/ml) were used as the model system for the study. mRNA and protein expressions were studied by qRT-PCR, ELISA, and western blot analysis. ROS production and cell viability were determined by fluorescence imaging and MTT assay respectively. In the presence of oxLDL, monocytes get differentiated into macrophages, which were confirmed by the increased expression of CD-36, b- D glucuronidase activity and by the morphological changes. OxLDL increased the mRNA and protein expression of ADAMTS-4 and TIMP-3 in monocytes/ macrophages. A significant increase in the mRNA and protein expression of TNF-α was also observed in oxLDL treated cells compared to untreated control. In the presence of NAC, the ROS scavenger, the production of NFκB and ADAMTS-4 was decreased significantly. Our study suggests that oxLDL significantly upregulated the expression of ADAMTS-4 in the monocyte/macrophage system. OxLDL mediated upregulation of ADAMTS-4 in hPBMCs involves TNF-α and ROS- NFκB pathway.

Aggregated Mycobacterium tuberculosis Enhances the Inflammatory Response

Mycobacterium tuberculosis (Mtb) bacilli readily aggregate. We previously reported that Mtb aggregates lead to phagocyte death and subsequent efficient replication in the dead infected cells. Here, we examined the transcriptional response of human monocyte derived macrophages to phagocytosis of aggregated Mtb relative to phagocytosis of non-aggregated single or multiple bacilli. Infection with aggregated Mtb led to an early upregulation of pro-inflammatory associated genes and enhanced TNFα signaling via the NFκB pathway. These pathways were significantly more upregulated relative to infection with single or multiple non-aggregated bacilli per cell. Phagocytosis of aggregates led to a decreased phagosome acidification on a per bacillus basis and increased phagocyte cell death, which was not observed when Mtb aggregates were heat killed prior to phagocytosis. Mtb aggregates, observed in a granuloma from a patient, were found surrounding a lesion cavity. These observations suggest that TB aggregation may be a mechanism for pathogenesis. They raise the possibility that aggregated Mtb, if spread from individual to individual, could facilitate increased inflammation, Mtb growth, and macrophage cell death, potentially leading to active disease, cell necrosis, and additional cycles of transmission.

IM-8 Significance of IL-1 pathways in Glioblastoma

Purpose: Previous studies have revealed that macrophages affect the prognosis of glioblastoma. However, there are still many unknown parts about the mechanism. In this study, we conducted an experiment with the aim of elucidating the mechanism by which tumor associated macrophages (TAM) work on tumors in the tumor microenvironment (TME). Method: Experiments were carried out using two glioblastoma cell strains, T98G, and U251. For clinical data, we analyzed it based on databases such as Protein Atlas, Ivy Glioblastoma Atlas, brain TIME database. Results: In 3D culture, we confirmed that IL-1β stimulation promoted glioblastoma cell proliferation and sphere formation. The addition of IL-1β increased mRNA expression of various cytokines such as IL-6 and CXCL8, and increased phosphorylation of STAT3 in arrays. When we administered IL-6 and CXCL8, the growth was significantly increased in cells administered with IL-6 and CXCL8. As a result, we speculated that STAT3 pathway and NFκB pathway via IL-6 and CXCL8 are involved in cell proliferation by IL-1β. In order to confirm these things, western blot was performed, and it was confirmed that phosphorylation of STAT3 and NFκB were increased. In addition, STAT3 inhibitors and NFκB inhibitors suppressed tumor growth. Clinically analysis was carried out based on the database, and it was found that IL-1β and macrophages were related. Furthermore, IL-1β was found in many cases around tumor necrosis. Discussion: This study clarifies some of the effects of IL-1β on glioblastoma. However, there are still many unknown points, and it is necessary to continue to consider them in the future.

Prunetin 4′-O-Phosphate, a Novel Compound, in RAW 264.7 Macrophages Exerts Anti-Inflammatory Activity viaSuppression of MAP Kinases and the NFκB Pathway

Biorenovation, a microbial enzyme-assisted degradation process of precursor compounds, is an effective approach to unraveling the potential bioactive properties of the derived compounds. In this study, we obtained a new compound, prunetin 4′-O-phosphate (P4P), through the biorenovation of prunetin (PRN), and investigated its anti-inflammatory effects in lipopolysaccharide (LPS)-treated RAW 264.7 macrophage cells. The anti-inflammatory effect of P4P was evaluated by measuring the production of prostaglandin-E2 (PGE2), nitric oxide (NO), which is an inflammation-inducing factor, and related cytokines such as tumor necrosis factor-α (TNFα), interleukin-1β (IL1β), and interleukin-6 (IL6). The findings demonstrated that P4P was non-toxic to cells, and its inhibition of the secretion of NO—as well as pro-inflammatory cytokines—was concentration-dependent. A simultaneous reduction in the protein expression level of pro-inflammatory proteins such as cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) was observed. Moreover, the phosphorylation of mitogen-activated protein kinases (MAPKs) such as extracellular signal-regulated kinases (ERKs), c-Jun N-terminal kinase (JNK), p38 MAPK (p38), and nuclear factor kappa B (NFκB) was downregulated. To conclude, we report that biorenovation-based phosphorylation of PRN improved its anti-inflammatory activity. Cell-based in vitro assays further confirmed that P4P could be applied in the development of anti-inflammatory therapeutics.

Trilobatin Alleviates Cognitive Deficits and Pathologies in an Alzheimer’s Disease Mouse Model

Alzheimer’s disease (AD) is the most common neurodegenerative disease nowadays that causes memory impairments. It is characterized by extracellular aggregates of amyloid-beta (Aβ), intracellular aggregates of hyperphosphorylated Tau (p-Tau), and other pathological features. Trilobatin (TLB), a natural flavonoid compound isolated from Lithocarpuspolystachyus Rehd., has emerged as a neuroprotective agent. However, the effects and mechanisms of TLB on Alzheimer’s disease (AD) remain unclear. In this research, different doses of TLB were orally introduced to 3×FAD AD model mice. The pathology, memory performance, and Toll-like receptor 4- (TLR4-) dependent inflammatory pathway protein level were assessed. Here, we show that TLB oral treatment protected 3×FAD AD model mice against the Aβ burden, neuroinflammation, Tau hyperphosphorylation, synaptic degeneration, hippocampal neuronal loss, and memory impairment. The TLR4, a pattern recognition immune receptor, has been implicated in neurodegenerative disease-related neuroinflammation. We found that TLB suppressed glial activation by inhibiting the TLR4-MYD88-NFκB pathway, which leads to the inflammatory factor TNF-α, IL-1β, and IL-6 reduction. Our study shows that TLR4 might be a key target of TLB in AD treatment and suggests a multifaceted target of TLB in halting AD. Taken together, our findings suggest a potential therapeutic effect of TLB in AD treatment.

Irisin Stimulates the Release of CXCL1 From Differentiating Human Subcutaneous and Deep-Neck Derived Adipocytes via Upregulation of NFκB Pathway

Thermogenic brown and beige adipocytes might open up new strategies in combating obesity. Recent studies in rodents and humans have indicated that these adipocytes release cytokines, termed “batokines”. Irisin was discovered as a polypeptide regulator of beige adipocytes released by myocytes, primarily during exercise. We performed global RNA sequencing on adipocytes derived from human subcutaneous and deep-neck precursors, which were differentiated in the presence or absence of irisin. Irisin did not exert an effect on the expression of characteristic thermogenic genes, while upregulated genes belonging to various cytokine signaling pathways. Out of the several upregulated cytokines, CXCL1, the highest upregulated, was released throughout the entire differentiation period, and predominantly by differentiated adipocytes. Deep-neck area tissue biopsies also showed a significant release of CXCL1 during 24 h irisin treatment. Gene expression data indicated upregulation of the NFκB pathway upon irisin treatment, which was validated by an increase of p50 and decrease of IκBα protein level, respectively. Continuous blocking of the NFκB pathway, using a cell permeable inhibitor of NFκB nuclear translocation, significantly reduced CXCL1 release. The released CXCL1 exerted a positive effect on the adhesion of endothelial cells. Together, our findings demonstrate that irisin stimulates the release of a novel adipokine, CXCL1, via upregulation of NFκB pathway in neck area derived adipocytes, which might play an important role in improving tissue vascularization.