• Asian-Australasian Journal of Animal Sciences
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• v.32 no.8
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• pp.1112-1121
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• 2019

Objective: Gram-negative bacteria lipopolysaccharide (LPS) has been reported to be associated with uterine impairment, embryonic resorption, ovarian dysfunction, and follicle retardation. Here, we aimed to investigate the toxic effects of LPS on the maturation ability and parthenogenetic developmental competence of bovine oocytes. Methods: First, we developed an in vitro model to study the response of bovine cumulusoocyte complexes (COCs) to LPS stress. After incubating germinal vesicle COCs in $10{\mu}g/mL$ of LPS, we analyzed the following three aspects: the expression levels of the LPS receptor toll-like receptor 4 (TLR4) in COCs, activities of intracellular signaling protein p38 mitogen-activated protein kinase (p38 MAPK) and nuclear factor-kappa B (NF-${\kappa}B$); and the concentrations of interleukin (IL)-$1{\beta}$, tumor necrosis factor (TNF)-${\alpha}$, and IL-6. Furthermore, we determined the effects of LPS on the maturation ability and parthenogenetic developmental competence of bovine oocytes. Results: The results revealed that LPS treatment significantly elevated TLR4 mRNA and protein expression levels in COCs. Exposure of COCs to LPS also resulted in a marked increase in activity of the intracellular signaling protein p-p38 MAPK and NF-${\kappa}B$. Furthermore, oocytes cultured in maturation medium containing LPS had significantly higher concentrations of the proinflammatory cytokines IL-$1{\beta}$, TNF-${\alpha}$, and IL-6. LPS exposure significantly decreased the first polar body extrusion rate. The cytoplasmic maturation, characterized by polar body extrusion and distribution of peripheral cortical granules, was significantly impaired in LPS-treated oocytes. Moreover, LPS exposure significantly increased intracellular reactive oxygen species levels and the relative mRNA abundance of the antioxidants thioredoxin (Trx), Trx2, and peroxiredoxin 1 in oocytes. Moreover, the early apoptotic rate and the release of cytochrome C were significantly increased in response to LPS. The cleavage, morula, and blastocyst formation rates were significantly lower in parthenogenetically activated oocytes exposed to LPS, while the incidence of apoptotic nuclei in blastocysts was significantly increased. Conclusion: Together, these results provide an underlying mechanism by which LPS impairs maturation potential in bovine oocytes.

• Biomolecules & Therapeutics
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• v.32 no.1
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• pp.104-114
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• 2024

Licochalcone C (LCC; PubChem CID:9840805), a chalcone compound originating from the root of Glycyrrhiza inflata, has shown anticancer activity against skin cancer, esophageal squamous cell carcinoma, and oral squamous cell carcinoma. However, the therapeutic potential of LCC in treating colorectal cancer (CRC) and its underlying molecular mechanisms remain unclear. Chemotherapy for CRC is challenging because of the development of drug resistance. In this study, we examined the antiproliferative activity of LCC in human colorectal carcinoma HCT116 cells, oxaliplatin (Ox) sensitive and Ox-resistant HCT116 cells (HCT116-OxR). LCC significantly and selectively inhibited the growth of HCT116 and HCT116-OxR cells. An in vitro kinase assay showed that LCC inhibited the kinase activities of EGFR and AKT. Molecular docking simulations using AutoDock Vina indicated that LCC could be in ATP-binding pockets. Decreased phosphorylation of EGFR and AKT was observed in the LCC-treated cells. In addition, LCC induced cell cycle arrest by modulating the expression of cell cycle regulators p21, p27, cyclin B1, and cdc2. LCC treatment induced ROS generation in CRC cells, and the ROS induction was accompanied by the phosphorylation of JNK and p38 kinases. Moreover, LCC dysregulated mitochondrial membrane potential (MMP), and the disruption of MMP resulted in the release of cytochrome c into the cytoplasm and activation of caspases to execute apoptosis. Overall, LCC showed anticancer activity against both Ox-sensitive and Ox-resistant CRC cells by targeting EGFR and AKT, inducing ROS generation and disrupting MMP. Thus, LCC may be potential therapeutic agents for the treatment of Ox-resistant CRC cells.

• Archives of Pharmacal Research
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• v.23 no.6
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• pp.605-612
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• 2000

Green tea polyphenols (GTP) have been demonstrated to suppress tumorigenesis in several chemical-induced animal carcinogenesis models, and predicted as promising chemopreventive agents in human. Recent studies of GTP extracts showed the involvement of mitogen-activated protein kinases (MAPKs) in the regulation of Phase II enzymes gene expression and induction of apoptosis. In the current work we compared the biological actions of five green tea catechins: (1) induction of ARE reporter gene, (2) activation of MAP kinases, (3) cytotoxicity in human hepatoma HepG2-C8 cells, and (4) caspase activation in human cervical squamous carcinoma HeLa cells. For the induction of phase IIgene assay, (-)-epigallocatechin-3-gallate (EGCG) and (-)-epicatechin-3-gallate (ECG) potently induced antioxidant response element (ARE)-mediated luciferase activity, with induction observed at 25 $\mu\textrm{m}$with EGCG. The induction of ARE reporter gene appears to be structurally related to the 3-gallate group. Comparing the activation of MAPK by the five polyphenols, only EGCG showed potent activation of all three MAPKs (ERK, JNK and p38) in a dose- and time-dependent manner, whereas EGC activated ERK and p38. In the concentration range of 25 $\mu\textrm{m}$ to 1 mM, EGCG and ECG strongly suppressed HepG2-ARE-C8 cell-growth. To elucidate the mechanisms of green tea polyphenol-induced apoptosis, we measured the activation of an important cell death protein, caspase-3 induced by EGCG, and found that caspase-3 was activated in a dose- and time-dependent manner. Interestingly, the activation of caspase-3 was a relatively late event (peaked at 16 h), whereas activation of MAPKs was much earlier (peaked at 2 h). It is possible, that at low concentrations of EGCG, activation of MAPK leads to ARE-mediated gene expression including phase II detoxifying enzymes. Whereas at higher concentrations of EGCG, sustained activation of MAPKs such as JNK leads to apoptosis. These mechanisms are currently under investigation in our laboratory. As the most abundant catechin in GTP extract, we found that EGCG potently induced ARE-mediated gene expression, activated MAP kinase pathway, stimulated caspase-3 activity, and induced apoptosis. These mechanisms together with others, may contribute to the overall chemopreventive function of EGCG itself as well as the GTP.

• Journal of Applied Biological Chemistry
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• v.63 no.2
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• pp.147-152
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• 2020

Farrerol is a flavanone isolated from the traditional Chinese herb 'Man-shan-hong' (Rhododendron dauricum L.). Farrerol has been reported to have various bioactivities including anti-oxidant, anti-inflammation, and anti-fungal. However, anti-cancer effect of farrerol has not yet been reported in MCF-7 breast cancer cells. In the present study, we investigated the anti-cancer effect of farrerol on MCF-7 cells. Farrerol decreased viability and induced apoptosis of MCF-7 cells in a dose dependent manner. Ferrerol exhibited a significant anti-proliferation effect with a half-maximal inhibitory concentration (IC₅₀) values of 145.04±1.4 μM in MTT assay, when MCF-7 cells were treated with ferrerol for 48 h. Also, ferrerol induced apoptotic bodies of MCF-7 cells as evaluated by TUNEL assay and Annexin V/PI staining using FACS. By mechanism of action, ferrerol regulated the activation of p38 mitogen-activated protein kinase and altered the expression level of BAX, Bcl-2, and Poly ADP Ribose Polymerase in MCF-7 cells. In summary, our finding demonstrated that ferrerol has anti-cancer effect through regulating the activation and expression of apoptosis-related proteins in MCF-7 cells.

• Journal of Life Science
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• v.20 no.7
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• pp.1093-1099
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• 2010

Little is known about the cardiovascular effects of Lycopene, an anti-cancer and anti-oxidative agent. In this study, we executed a series of experiments with vascular endothelial cells to disclose the cardiovascular functions of lycopene. From our in vitro experiments, lycopene was determined to act as a stimulant to induce endothelial cell proliferation and migration. In addition, lycopene was shown to inhibit lipopolysaccharide (LPS)-induced adhesion of THP-1 leukocytes to endothelial cells, as well as activating mitogen activated protein kinase (MAPK) family members, ERK, JNK and p38 MAPK. Both ERK and p38 MAPK were involved in lycopene-induced cell proliferation, while JNK was involved in lycopene-dependent cell migration. Taken together, lycopene activates MAPK family members which regulate cell proliferation and migration. Lycopene differentially blocks LPS-dependent adhesion for THP-1 to endothelial cells, indicating that lycopene is likely to regulate a variety of vascular functions.

• The Korea Journal of Herbology
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• v.28 no.2
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• pp.67-73
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• 2013

Objective : Lithospermum Erythrorhizon (LE) has been used as an anti-bacterial and anti-inflammatory agent. However, it is unclear that LE aqueous extract could show the anti-inflammatory effects in RAW 264.7cells. The purpose of this study was to investigate the anti-inflammatory effect of aqueous extract from LE on lipopolysaccharide (LPS) - induced inflammatory response. Methods : To measure out the cytotoxicity of LE, we performed the MTT assay. To evaluate the anti-inflammatory effects of LE, we examined the inflammatory mediators such as nitric oxide (NO), prostaglandin E2 ($PGE_2$) and pro-inflammatory cytokines (tumor necrosis factor (TNF)-${\alpha}$, interleukin, (IL)-$1{\beta}$ and (IL)-6) on RAW 264.7 cells. We also examined molecular mechanisms such as mitogen-activated protein kinases (MAPKs) and nuclear factor-B (NF-${\kappa}B$) activation by western blot. Results : Aqueous Extract from LE itself did not have any cytotoxic effect in RAW 264.7 cells. Aqueous extract from LE inhibited LPS-induced productions of inflammatory mediators such as NO, $PGE_2$, and pro-inflammatory cytokines including TNF-${\alpha}$, IL-$1{\beta}$ and IL-6 in RAW 264.7cells. In addition, LE inhibited the phosphorylation of p38 kinases (p38), c-Jun $NH_2$-terminal kinase (JNK), and NF-${\kappa}B$ activation in RAW 264.7 cells. Conclusion : LE down-regulated LPS-induced production of inflammatory mediators through the inhibition of p38, JNK and NF-${\kappa}B$ activation. Taken together, these results could provide the evidence for the anti-inflammatory effects of LE. Therefore, LE may be a novel target in the management of inflammation and help to support a potential strategy for prevention and therapy of inflammatory diseases.

• Korean Journal of Plant Resources
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• v.34 no.1
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• pp.23-30
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• 2021

Hemistepta lyrata Bunge (HL) has been used as a folk remedy to treat cancer, inflammation, bleeding, hemorrhoids and fever, and leaves and young shoots have been used as famine food. Nevertheless, the biological activities and underlying mechanisms of the anti-inflammatory effects remain unclear. In this study, it was undertaken to explore the functions of the aerial part of HL as a suppressor of inflammation by using RAW 264.7 cells. As immune response parameters, the productions of as nitric oxide (NO) and prostaglandin E2 (PGE2), cytokines such tumor necrotic factor (TNF)-α and interleukin (IL)-6 were evaluated. Although the release of TNF-α remained unchanged in HL-treated RAW 264.7 cells, the productions of NO, PGE2 and IL-6 were significantly increased at concentrations with no cytotoxicity. Furthermore, HL significantly attenuated the mitogen-activated protein kinases (MAPK) pathway including decreasing the phosphorylation of the extracellular signal-regulated kinase (ERK1/2) and p38 mitogen-activated protein kinases. Collectively, this study provides evidence that HL inhibits the production of major pro-inflammatory molecules in LPS-stimulated RAW 264.7 cells via suppression of ERK and P38 MAPK signaling pathways. These findings suggest that the beneficial therapeutic effects of HL may be attributed partly to its ability to modulate immune functions in macrophages.

• Journal of the korean academy of Pediatric Dentistry
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• v.29 no.3
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• pp.337-344
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• 2002

Runx2, a Runt-related osteoblast-specific transcription factor, is essential for osteoblast differentiation and function. Runx2 was identified as a key regulator of osteoblast-specific gene expression through its binding to the OSE2 element present in these genes. However, little is known about the signaling mechanism regulating Runx2 activity. This study examines the role of protein kinase C (PKC) pathway and mitogen-activated protein kinase (MAPK) pathway in regulating Runx2 and bone marker genes (osteopontin; OP, osteocalcin; OC). Luciferase assay and Northern blot analysis suggested that the stimulation of PKC by PMA increased transcription activity of Runx2 and bone marker genes (OP and OC) and also increased expression of Runx2. The stimulation of MAPK by okadaic acid increased transcription activity of Runx2 and bone marker genes (OP and OC). Pretreatment with PD98059 (Erk pathway inhibitor) and SB203580 (P38 pathway inhibitor) prior to PMA treatment decreased PMA stimulated Runx2 activity. Together these results indicate that both PKC and MAPKs are involved in the regulation of Runx2 activity and also the stimulation of Runx2 transcriptional activity by the PKC pathway is through activation of MAPK pathway.

• Journal of Ginseng Research
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• v.39 no.1
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• pp.29-37
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• 2015

Background: Panax ginseng (i.e., ginseng) root is extensively used in traditional oriental medicine. It is a modern pharmaceutical reagent for preventing various human diseases such as cancer. Ginsenosidesd-the major active components of ginsengd-exhibit immunomodulatory effects. However, the mechanism and function underlying such effects are not fully elucidated, especially in human monocytes and dendritic cells (DCs). Methods: We investigated the immunomodulatory effect of ginsenosides from Panax ginseng root on $CD14^+$ monocytes purified from human adult peripheral blood mononuclear cells (PBMCs) and on their differentiation into DCs that affect $CD4^+$ T cell activity. Results: After treatment with ginsenoside fractions, monocyte levels of tumor necrosis factor (TNF)-${\alpha}$, interleukin (IL)-6, and IL-10 increased through phosphorylation of extracellular signal-regulated kinase (ERK)1/2 and c-Jun N-terminal kinase (JNK), but not p38 mitogen-activated protein kinase (MAPK). After treatment with ginsenoside fractions, TNF-${\alpha}$ production and phosphorylation of ERK1/2 and JNK decreased in lipopolysaccharide (LPS)-sensitized monocytes.We confirmed that DCs derived from $CD14^+$ monocytes in the presence of ginsenoside fractions (Gin-DCs) contained decreased levels of the costimulatory molecules CD80 and CD86. The expression of these costimulatory molecules decreased in LPS-treated DCs exposed to ginsenoside fractions, compared to their expression in LPS-treated DCs in the absence of ginsenoside fractions. Furthermore, LPS-treated Gin-DCs could not induce proliferation and interferon gamma (IFN-${\gamma}$) production by $CD4^+$ T cells with the coculture of Gin-DCs with $CD4^+$ T cells. Conclusion: These results suggest that ginsenoside fractions from the ginseng root suppress cytokine production and maturation of LPS-treated DCs and downregulate $CD4^+$ T cells.

• BMB Reports
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• v.45 no.8
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• pp.482-487
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• 2012

To identify the novel inhibitors of endoplasmic reticulum stress-induced cell death, we performed a high throughput assay with a chemical library containing a total of 3,280 bioactive small molecules. Cyclosporine A and bromocriptine were identified as potent inhibitors of thapsigargiin-induced cell death (cut-off at $4{\sigma}$ standard score). However, U74389G, the potent inhibitor of lipid peroxidation had lower activity in inhibiting cell death. The inhibition effect of cyclosporine A and bromocriptine was specific for only thapsigargin-induced cell death. The mechanism of inhibition by these compounds was identified as modification of the expression of glucose regulated protein-78 (GRP-78/Bip) and inhibition of phosphorylation of p38 mitogen activated protein kinase (MAPK). However, these compounds did not inhibit the same events triggered by tunicamycin, which was in agreement with the cell survival data. We suggest that the induction of protective unfolded protein response by these compounds confers resistance to cell death. In summary, we identified compounds that may provide insights on cell death mechanisms stimulated by ER stress.