Sea Hare Hydrolysate-Induced Reduction of Human Non-Small Cell Lung Cancer Cell Growth through Regulation of Macrophage Polarization and Non-Apoptotic Regulated Cell Death Pathways.

Sea hare-derived compounds induce macrophage activation and reduce asthmatic parameters in mouse models of allergic asthma. These findings led us to study the role of sea hare hydrolysates (SHH) in cancer pathophysiology. SHH treatment-induced M1 macrophage activation in RAW264.7 cells, peritoneal macrophages, and THP-1 cells, as did lipopolysaccharide (LPS) (+ INF-γ), whereas SHH reduced interleukin (IL)-4 (+IL-13)-induced M2 macrophage polarization. In addition, SHH treatment inhibited the actions of M1 and M2 macrophages, which have anticancer and pro-cancer effects, respectively, in non-small cell lung cancer cells (A549 and HCC-366) and tumor-associated macrophages (TAMs). Furthermore, SHH induced G2/M phase arrest and cell death in A549 cells. SHH also downregulated STAT3 activation in macrophages and A549 cells, and the down-regulation was recovered by colivelin, a STAT3 activator. SHH-induced reduction of M2 polarization and tumor growth was blocked by colivelin treatment. SHH-induced cell death did not occur in the manner of apoptotic signaling pathways, while the death pattern was mediated through pyroptosis/necroptosis, which causes membrane rupture, formation of vacuoles and bleb, activation of caspase-1, and secretion of IL-1ß in SHH-treated A549 cells. However, a combination of SHH and colivelin blocked caspase-1 activation. Z-YVAD-FMK and necrostatin-1, pyrotosis and necroptosis inhibitors, attenuated SHH's effect on the cell viability of A549 cells. Taken together, SHH showed anticancer effects through a cytotoxic effect on A549 cells and a regulatory effect on macrophages in A549 cells. In addition, the SHH-induced anticancer effects were mediated by non-apoptotic regulated cell death pathways under STAT3 inhibition. These results suggest that SHH may be offered as a potential remedy for cancer immunotherapy.

Evaluation of antioxidant activities of various solvent extract from Sargassum serratifolium and its major antioxidant components.

Sargassum serratifolium has been known to contain a high level of meroterpenoids as antioxidant components. We investigated antioxidant activities and active components in various solvent extracts from S. serratifolium. Ethyl acetate, ethanol, and methanol extracts showed relatively strong DPPH, ABTs, and superoxide radical scavenging activities. Hexane and ethyl acetate extract showed the strongest hydroxyl radical and reactive oxygen species (ROS), respectively, scavenging activities. Sargahydroquinoic acid (SHQA), sargachromanol (SCM) and sargaquinoic acid (SQA) were main antioxidant components in S. serratifolium. Ethanol extract showed the highest levels of SHQA, SCM, and SQA which comprised to be 227 ±â€¯6.31 mg/g. SHQA and SCM exhibited stronger antioxidant capacities than SQA based on lower IC50 values in ROS, DPPH, ABTs, and superoxide radical scavenging assays. The result showed that ethanol is the most efficient extracting solvent for the active components from S. serratifolium and the plant has the potential as a natural antioxidant.

6,6'-Bieckol suppresses inflammatory responses by down-regulating nuclear factor-κB activation via Akt, JNK, and p38 MAPK in LPS-stimulated microglial cells.

OBJECTIVE: Microglial activation has been implicated in many neurological disorders for its inflammatory and neurotrophic effects. In this study, we investigated the pharmaceutical properties of 6,6'-bieckol on the regulation of nuclear factor-κB (NF-κB) activation responsible to the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX)-2 using lipopolysaccharide (LPS)-stimulated BV2 and murine primary microglial cells. Meterials and methods: The levels of nitric oxide (NO), prostaglandin E2 (PGE)2, and pro-inflammatory cytokines were measured by Griess assay and enzyme-linked immunosorbent assay. The levels of iNOS, COX-2, mitogen-activated protein kinases (MAPKs), and Akt were measured using Western blot. Nuclear translocation and transcriptional activation of NF-κB were determined by immunofluorescence and reporter gene assay, respectively. RESULTS: We found that 6,6'-bieckol decreased the expression of iNOS and COX-2 as well as pro-inflammatory cytokines in LPS-stimulated BV2 and primary microglial cells in a dose-dependent manner. 6,6'-Bieckol inhibited activation of NF-κB by preventing the degradation of inhibitor κB (IκB)-α and led to prevent the nuclear translocation of NF-κB/p65 subunit. Moreover, 6,6'-bieckol inhibited the phosphorylation of Akt, JNK, and p38 MAPK. DISCUSSION AND CONCLUSION: These results indicate that the anti-inflammatory effect of 6,6'-bieckol on LPS-stimulated microglial cells is mainly regulated by the inhibition of IκB-α/NF-κB and JNK/p38 MAPK/Akt pathways, supporting biochemical characteristics of the compound for therapeutic agent against neuroinflammatory diseases caused by microglial activation.

Phlorofucofuroeckol B suppresses inflammatory responses by down-regulating nuclear factor κB activation via Akt, ERK, and JNK in LPS-stimulated microglial cells.

Microglial activation has been implicated in many neurological disorders for its inflammatory and neurotrophic effects. In this study, we investigated the effects of phlorofucofuroeckol B (PFF-B) isolated from Ecklonia stolonifera, on the production of inflammatory mediators in lipopolysaccharide (LPS)-stimulated microglia. PFF-B decreased secretion of pro-inflammatory cytokines including tumor necrosis factor α, interleukin (IL)-1ß, and IL-6 and the expression of pro-inflammatory proteins such as cyclooxygenase-2 and inducible nitric oxide synthase in LPS-stimulated BV-2 cells. Profoundly, PFF-B inhibited activation of nuclear factor kappaB (NF-κB) by preventing the degradation of inhibitor κB-α (IκB-α), which led to prevent the nuclear translocation of p65 NF-κB subunit. Moreover, PFF-B inhibited the phosphorylation of Akt, ERK, and JNK. These results indicate that the anti-inflammatory effect of PFF-B on LPS-stimulated microglial cells is mainly regulated by the inhibition of IκB-α/NF-κB and Akt/ERK/JNK pathways. Our study suggests that PFF-B can be considered as a therapeutic agent against neuroinflammation by inhibiting microglial activation.

Hexane fraction from Sargassum fulvellum inhibits lipopolysaccharide-induced inducible nitric oxide synthase expression in RAW 264.7 cells via NF-κB pathways.

Sargassum fulvellum (Turner) C. Agardh has been used to treat various inflammatory diseases, including lump, dropsy, swollen and painful scrotum, and urination problems for several centuries with no side effects. This study aims to investigate the anti-inflammatory effect of the hexane fraction of S. fulvellum (HFS) in lipopolysaccharide (LPS)-stimulated RAW 264.7 cells and phorbol 12-myristate 13-acetate (PMA)-induced mouse-ear edema. The anti-inflammatory activity of HFS in LPS-stimulated RAW 264.7 cells was investigated by assessing the inhibition of nitric oxide (NO) and pro-inflammatory cytokine production during Griess reaction and enzyme-linked immunosorbent assay (ELISA), respectively. The molecular mechanisms that underlie the anti-inflammatory action of HFS were investigated by analyzing the activation of transcription factor and its upstream signaling proteins. Additionally, an in vivo study of the anti-inflammatory effect of HFS was carried out using PMA-induced mouse-ear edema. HFS inhibited LPS-induced NO production in a dose-dependent manner and suppressed the expression of inducible NO synthase (iNOS) in the RAW 264.7 cells. Further, HFS reduced the production of pro-inflammatory cytokines in the LPS-stimulated RAW 264.7 cells. HFS significantly inhibited LPS-induced nuclear factor kappa B (NF-κB) transcriptional activity and NF-κB translocation into the nucleus by preventing degradation of inhibitor κB-α. Moreover, HFS inhibited the activation of Akt and mitogen-activated protein kinases (MAPKs) in the LPS-stimulated RAW 264.7 cells. Furthermore, HFS suppressed PMA-induced mouse-ear edema. The above data indicate that the anti-inflammatory effects of HFS on LPS-stimulated cells are associated with the suppression of NF-κB through the inhibition of MAPKs and Akt phosphorylation.