• Molecules and Cells
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• v.24 no.1
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• pp.95-104
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• 2007

The mechanism of acacetin-induced apoptosis of human breast cancer MCF-7 cells was investigated. Acacetin caused 50% growth inhibition ($IC_{50}$) of MCF-7 cells at $26.4{\pm}0.7{\mu}M$ over 24 h in the MTT assay. Apoptosis was characterized by DNA fragmentation and an increase of sub-G1 cells and involved activation of caspase-7 and PARP (poly-ADP-ribose polymerase). Maximum caspase 7 activity was observed with $100{\mu}M$ acacetin for 24 h. Caspase 8 and 9 activation cascades mediated the activation of caspase 7. Acacetin caused a reduction of Bcl-2 expression leading to an increase of the Bax:Bcl-2 ratio. It also caused a loss of mitochondrial membrane potential that induced release of cytochrome c and apoptosis inducing factor (AIF) into the cytoplasm, enhancing ROS generation and subsequently resulting in apoptosis. Pretreatment of cells with N-acetylcysteine (NAC) reduced ROS generation and cell growth inhibition, and pretreatment with NAC or a caspase 8 inhibitor (Z-IETD-FMK) inhibited the acacetin-induced loss of mitochondrial membrane potential and release of cytochrome c and AIF. Stress-activated protein kinase/c-Jun $NH_4$-terminal kinase 1/2 (SAPK/JNK1/2) and c-Jun were activated by acacetin but extracellular-regulated kinase 1/2 (Erk1/2) nor p38 mitogen-activated protein kinase (MAPK) were not. Our results show that acacetin-induced apoptosis of MCF-7 cells is mediated by caspase activation cascades, ROS generation, mitochondria-mediated cell death signaling and the SAPK/JNK1/2-c-Jun signaling pathway, activated by acacetin-induced ROS generation.

• Preventive Nutrition and Food Science
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• v.15 no.2
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• pp.137-142
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• 2010

Previous studies report that organo-sulfur compounds derived from garlic inhibited smooth muscle cell (SMC) proliferation and induced apoptosis of cancer cells. Recently, lipid-soluble compounds such as diallyl sulfides (DAS) and diallyl disulfides (DADS) have been reported to more effectively suppress tumor cell proliferation. However, there were few studies on the suppressive effects of lipid-soluble garlic sulfur compounds on the proliferation and migration of vascular smooth muscle cells (VSMC). Therefore, this study investigated the effect of DAS and DADS on VSMC proliferation/migration induced by oleic acid (OA), a principal fatty acid in circulating triglyceride of blood stream. Assays performed include a tetrazole (MTT) assay, a wound healing assay and a Western blots. VSMC proliferations were enhanced by OA in a dose-dependent manner at concentrations of $10{\sim}50\;{\mu}M$ and inhibited by DAS and DADS compared to non-treated control. OA-induced proliferations were also attenuated by DAS and DADS. OA-induced cell migrations were 2.5 times higher than non-treated control, and they were significantly attenuated by DAS (32% at $150\;{\mu}M$ and 50% at $200\;{\mu}M$) and DADS (40% at $150\;{\mu}M$ and 46% at $200\;{\mu}M$). OA-induced cell migration was also attenuated by PD98059 (ERK inhibitor), SB203580 (P38 inhibitor) and particularly by LY204002 (PI3K inhibitor) and SP600125 (JNK2 inhibitor). Additionally, Western blot assays showed that OA-induced JNK1/2-phosphorylation was down-regulated after treatment with DAS and DADS. In conclusion, the findings of our study support the idea that DAS and DADS may have a suppressive effect on the proliferation and migration of OA-induced VSMC and that this effect may be partly associated with PI3K and JNK2 pathways.

• Parasites, Hosts and Diseases
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• v.58 no.4
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• pp.393-402
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• 2020

Toxoplasma gondii is an intracellular parasite that causes severe disease when the infection occurs during pregnancy. Adenosine is a purine nucleoside involved in numerous physiological processes; however, the role of adenosine receptors in T. gondii-induced trophoblast cell function has not been investigated until now. The goal of the present study was to evaluate the intracellular signaling pathways regulated by adenosine receptors using a HTR-8/SVneo trophoblast cell model of T. gondii infection. HTR8/SVneo human extravillous trophoblast cells were infected with or without T. gondii and then evaluated for cell morphology, intracellular proliferation of the parasite, adenosine receptor expression, TNF-α production and mitogen-activated protein (MAP) kinase signaling pathways triggered by adenosine A₃ receptor (A₃AR). HTR8/SVneo cells infected with T. gondii exhibited an altered cytoskeletal changes, an increased infection rate and reduced viability in an infection time-dependent manner. T. gondii significantly promoted increased TNF-α production, A₃AR protein levels and p38, ERK1/2 and JNK phosphorylation compared to those observed in uninfected control cells. Moreover, the inhibition of A₃AR by A₃AR siRNA transfection apparently suppressed the T. gondii infection-mediated upregulation of TNF-α, A₃AR production and MAPK activation. In addition, T. gondii-promoted TNF-α secretion was dramatically attenuated by pretreatment with PD098059 or SP600125. These results indicate that A₃AR-mediated activation of ERK1/2 and JNK positively regulates TNF-α secretion in T. gondii-infected HTR8/SVneo cells.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.1
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• pp.104-112
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• 2009

The purpose of this study was to investigate the anti-inflammatory effects of extract from GuBoEum(GBE) on the peritoneal macrophage. To evaluate anti-inflammatory effects of GBE. I measured cytokines (interleukin-6; IL-6, interleukin-12; IL-12, tumor necrosis factor-$\alpha$; TNF-$\alpha$) and nitric oxide (NO) production in lipopolysacchride (LPS)-induced macrophages. Furthermore, I examined molecular mechanism using western blot and also LPS-induced endotoxin shock. Extract from GBE does not have any cytotoxic effect in the peritoneal macrophages. Extract from GBE reduced LPS-induced IL-6, TNF-$\alpha$, IL-12 and NO production in peritoneal macrophages. GBE inhibited the activation of extracelluar signal-regulated kinase (ERK), C-Jun $NH_2$-terminal kinase (JNK) but not of p38, degradation of $I{\kappa}B-{\alpha}$ in the LPS-stimulated peritoneal macrophages. GBE inhibited the production of TNF-$\alpha$, IL-6 and IL-12 in serum after LPS injection. These results suggest that GBE may inhibit the production of TNF-$\alpha$, IL-6, and IL-12 through inhibition of ERK and JNK activation, and that GBE may be beneficial oriental medicine for inflammatory diseases.

• Journal of Oriental Neuropsychiatry
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• v.24 no.3
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• pp.309-320
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• 2013

Objectives : There is a possibility LRE as remedy in Alzheimer disease (AD), but it's nerve protection effect and mechanism have to be elucidate. In this research, we applied LRE on $A{\beta}_{25-35}$ pre-treated SH-SY5Y cells, to find out the nerve protection effect and mechanism in AD cell model. Methods : We tried to confirm that effect by experimenting with 20, 50, and $100{\mu}g/ml$ concentration of LRE as a medicine. Next experiment, we assessed damage effect which induced $A{\beta}_{25-35}$, known to cause AD, on SH-SY5Y cell. In addition, cellular viability test is executed under $H_2O_2$ treatment condition in a SH-SY5Y cell. Results : 1. In $A{\beta}_{25-35}$ treated SH-SY5Y cell, LRE exhibited an anti-phosphorylation effect about tau protein, JNK, and IKB. 2. LRE prevent nerve cell apoptosis, which indued $A{\beta}_{25-35}$ and oxidative stress, modify JNK engaged synaptic structure and $NF{\kappa}B$ induced p75-neurotrophin receptor polymorphism. Conclusions : We found that LRE prevented oxidative stress-induced cellular destruction, for example, increased SOD activity of $A{\beta}_{25-35}$ treated SH-SY5Y cell and reduced toxicity of oxygen free radical. Consequently, the ingredients of LRE have a role as a catalyzer for $A{\beta}_{25-35}$ clearance and as scavenger for active oxygen free radical.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.5
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• pp.435-440
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• 2013

While the anti-apoptotic effect of paricalcitol has been demonstrated in various animal models, it is not yet clear whether paricalcitol attenuates the apoptosis in gentamicin (GM)-induced kidney injury. We investigated the effect of paricalcitol on apoptotic pathways in rat kidneys damaged by GM. Rats were randomly divided into three groups: 1) Control group (n=8), where only vehicle was delivered, 2) GM group (n=10), where rats were treated with GM (150 mg/kg/day) for 7 days, 3) PARI group (n=10), where rats were co-treated with paricalcitol (0.2 ${\mu}g/kg/day$) and GM for 7 days. Paricalcitol attenuated renal dysfunction by GM administration in biochemical profiles. In terminal deoxynucleotidyl transferase dUTP nick end labeling staining, increased apoptosis was observed in GM group, which was reversed by paricalcitol co-treatment. Immunoblotting using protein samples from rat cortex/outer stripe of outer medulla showed increased Bax/Bcl-2 ratio and cleaved form of caspase-3 in GM group, both of which were reversed by paricalcitol. The phosphorylated Jun-N-terminal kinase (JNK) expression was increase in GM, which was counteracted by paricalcitol. The protein expression of p-Akt and nitro-tyrosine was also enhanced in GM-treated rats compared with control rats, which was reversed by paricalcitol co-treatment. Paricalcitol protects GM-induced renal injury by antiapoptotic mechanisms, including inhibition of intrinsic apoptosis pathway and JNK.

• The Korean Journal of Physiology and Pharmacology
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• v.17 no.2
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• pp.139-147
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• 2013

Lysolipids such as LPA, S1P and SPC have diverse biological activities including cell proliferation, differentiation, and migration. We investigated signaling pathways of LPA-induced contraction in feline esophageal smooth muscle cells. We used freshly isolated smooth muscle cells and permeabilized cells from cat esophagus to measure the length of cells. Maximal contraction occurred at $10^{-6}M$ and the response peaked at 30s. To identify LPA receptor subtypes in cells, western blot analysis was performed with antibodies to LPA receptor subtypes. LPA1 and LPA3 receptor were detected at 50 kDa and 44 kDa. LPA-induced contraction was almost completely blocked by LPA receptor (1/3) antagonist KI16425. Pertussis toxin (PTX) inhibited the contraction induced by LPA, suggesting that the contraction is mediated by a PTX-sensitive G protein. Phospholipase C (PLC) inhibitors U73122 and neomycin, and protein kinase C (PKC) inhibitor GF109203X also reduced the contraction. The PKC-mediated contraction may be isozyme-specific since only $PKC{\varepsilon}$ antibody inhibited the contraction. MEK inhibitor PD98059 and JNK inhibitor SP600125 blocked the contraction. However, there is no synergistic effect of PKC and MAPK on the LPA-induced contraction. In addition, RhoA inhibitor C3 exoenzyme and ROCK inhibitor Y27632 significantly, but not completely, reduced the contraction. The present study demonstrated that LPA-induced contraction seems to be mediated by LPA receptors (1/3), coupled to PTX-sensitive G protein, resulting in activation of PLC, PKC-${\varepsilon}$ pathway, which subsequently mediates activation of ERK and JNK. The data also suggest that RhoA/ROCK are involved in the LPA-induced contraction.

• Biomedical Science Letters
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• v.19 no.1
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• pp.1-8
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• 2013

Parkin is known to be a tumor suppressor protein. Previously, we determined that parkin expression restores susceptibility to TNF-${\alpha}$-induced death of HeLa cells, a human cervical cancer cell line resistant to TNF-${\alpha}$-induced cell death. MMP-3 is a zinc-dependent protease recently reported to activate intracellular apoptotic signaling. In this study we examined the regulation of MMP-3 expression by parkin in TNF-${\alpha}$-treated HeLa cells. Furthermore, we investigated the signaling pathway involved in parkin-induced expression of MMP-3. We found that HeLa cells exhibit low levels of MMP-3 but is induced after introduction of the parkin gene into HeLa cells. Furthermore, MMP-3 expression increased further when parkin expressing cells were treated with TNF-${\alpha}$. Using chemical inhibitors of cell signaling pathways, we found that MEK-1 (PD98059), PI3K (LY294002), p38 MAPK (SB203580), and JNK inhibitors alleviated parkin-induced up-regulation of MMP-3. Finally, we show that TNF-${\alpha}$-induced cell death in parkin expressing cells is inhibited by using a MMP-3 inhibitor. These results suggest that parkin expression induces prolonged expression of MMP-3 via MEK-1, PI3K, MAPK, and JNK pathway in HeLa cells allowing the HeLa cells to become sensitive to TNF-${\alpha}$-induced cell death. These results implicate a role of MMP-3 in parkin-induced cell death in TNF-${\alpha}$ treated HeLa cells.

• Journal of Physiology & Pathology in Korean Medicine
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• v.31 no.6
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• pp.328-333
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• 2017

Desomodii Herba (DH) has been shown to exhibit pharmacologyical activities, such as increase myocaridal contraction and secretion of hepatic bile. DH is used to reduce pain caused by rheumatoid arthritis(RA) in Korean medicine. However, the DH exact(DHE) effect and mechanism on rheumatoid arthritis are unknown. In this study, we aimed at the inhibitory effect of DHE on rheumatoid arthritis, and investigated the effect in collagen-induced mice arthritis model and TNF-${\alpha}$ induced MMP-1 and MMP-3 expression including the molecular basis in rheumatoid arthritis synovial fibroblasts (RASFs).The effect of DHE on RA was measured by clinical scoring system. In RASFs, expression of MMP-1 and MMP-3 was assessed by Western blotting and real-time PCR. Also, Western blotting used to evaluate the phosphorylation levels of p38, ERK and JNK and activation of NF-${\kappa}B$ and AP-1. Our results showed that DHE reduced collagen-induced arthritis in mice. DHE inhibits TNF-${\alpha}$ induced MMP-1 and MMP-3 expression and mRNA levels in RASFs. The inhibitory effect of DHE was mediated by the inhibition of the AP-1/JNK signaling pathway. Taken together, our results suggest that the DHE may have preventive potential for rheumatoid arthritis.

• Biomolecules & Therapeutics
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• v.22 no.5
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• pp.390-399
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• 2014

Chalcones (1,3-diaryl-2-propen-1-ones), a flavonoid subfamily, are widely known for their anti-inflammatory properties. Propenone moiety in chalcones is known to play an important role in generating biological responses by chalcones. In the present study, we synthesized chalcone derivatives structurally modified in propenone moiety and examined inhibitory effect on nitric oxide (NO) production and its potential mechanisms. Among the chalcone derivatives used for this study, TI-I-174 (3-(2-Hydroxyphenyl)-1-(thiophen-3-yl)prop-2-en-1-one) most potently inhibited lipopolysaccharide (LPS)-stimulated nitrite production in RAW 264.7 macrophages. TI-I-174 treatment also markedly inhibited inducible nitric oxide synthase (iNOS) expression. However, TI-I-174 did not significantly affect production of IL-6, cyclooxygenase-2 (COX-2) and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), implying that TI-I-174 inhibits production of inflammatory mediators in a selective manner. Treatment of macrophages with TI-I-174 significantly inhibited transcriptional activity of activator protein-1 (AP-1) as determined by luciferase reporter gene assay, whereas nuclear factor-${\kappa}B$ (NF-${\kappa}B$) activity was not affected by TI-I-1744. In addition, TI-I-174 significantly inhibited activation of c-Jun-N-Terminal kinase (JNK) without affecting ERK1/2 and p38MAPK, indicating that down-regulation of iNOS gene expression by TI-I-174 is mainly attributed by blockade of JNK/AP-1 activation. We also demonstrated that TI-I-174 treatment led to an increase in heme oxygenase-1 (HO-1) expression both at mRNA and protein level. Transfection of siRNA targeting HO-1 reversed TI-I-174-mediated inhibition of nitrite production. Taken together, these results indicate that TI-I-174 suppresses NO production in LPS-stimulated RAW 264.7 macrophages via induction of HO-1 and blockade of AP-1 activation.