• The Korean Journal of Physiology and Pharmacology
• /
• 제13권5호
• /
• pp.401-408
• /
• 2009

$K^+$-$Cl^-$-cotransport (KCC) has been reported to have various cellular functions, including proliferation and apoptosis of human cancer cells. However, the signal transduction pathways that control the activity of KCC are currently not well understood. In this study we investigated the possible role of phospholipase $A_2$ ($PLA_2$)-arachidonic acid (AA) signal in the regulatory mechanism of KCC activity. Exogenous application of AA significantly induced $K^+$ efflux in a dose-dependent manner, which was completely blocked by R-(+)-[2-n-butyl-6,7 -dichloro-2-cyclopentyl-2,3-dihydro-1-oxo-1Hinden-5-yl]oxy]acetic acid (DIOA), a specific KCC inhibitor. N-Ethylmaleimide (NEM), a KCC activatorinduced $K^+$ efflux was significantly suppressed by bromoenol lactone (BEL), an inhibitor of the calciumindependent $PLA_2$ ($iPLA_2$), whereas it was not significantly altered by arachidonyl trifluoromethylketone ($AACOCF_3$) and p-bromophenacyl bromide (BPB), inhibitors of the calcium-dependent cytosolic $PLA_2$ ($cPLA_2$) and the secretory $PLA_2$ ($sPLA_2$), respectively. NEM increased AA liberation in a doseand time-dependent manner, which was markedly prevented only by BEL. In addition, the NEM-induced ROS generation was significantly reduced by DPI and BEL, whereas $AACOCF_3$ and BPB did not have an influence. The NEM-induced KCC activation and ROS production was not significantly affected by treatment with indomethacin (Indo) and nordihydroguaiaretic acid (NDGA), selective inhibitors of cyclooxygenase (COX) and lipoxygenase (LOX), respectively. Treatment with 5,8,11,14-eicosatetraynoic acid (ETYA), a non-metabolizable analogue of AA, markedly produced ROS and activated the KCC. Collectively, these results suggest that $iPLA_2$-AA signal may be essentially involved in the mechanism of ROS-mediated KCC activation in HepG2 cells.

• Journal of Ginseng Research
• /
• 제37권2호
• /
• pp.187-193
• /
• 2013

The effect of Korean red ginseng (KRG) on diabetic renal damage was investigated using streptozotocin (STZ)-induced diabetic rats. The diabetic rats showed loss of body weight gain, and increases in kidney weight and urine volume, whereas the oral administration of KRG at a dose of 100 or 250 mg/kg of body weight per day for 28 d prevented these diabetes-induced physiological abnormalities. Among the kidney function parameters, elevated plasma levels of urea nitrogen and creatinine in diabetic control rats tended to be lowered in KRG-treated rats. In addition, administration of KRG at a dose of 100 mg/kg body weight in the diabetic rats showed significant decreases in serum glucose and tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$), implying that KRG might prevent the pathogenesis of diabetic complications caused by impaired glucose metabolism and oxidative stress. KRG also significantly reduced advanced glycation end product (AGE) formation and secretion from kidney of diabetic rats. Furthermore, KRG decreased the levels of N-(carboxymethyl) lysine and expression of AGE receptor. KRG also reduced the overexpression of cyclooxygenase-2 and inducible nitric oxide synthase in the kidney via deactivation of nuclear factor-kappa B. We also found that KRG prevented STZ-induced destruction of glomerular structure and significantly suppressed high glucose-induced fibronectin production. Taken together, KRG ameliorates abnormalities associated with diabetic nephropathy through suppression of inflammatory pathways activated by TNF-${\alpha}$ and AGEs. These findings indicate that KRG has a beneficial effect on pathological conditions associated with diabetic nephropathy.

• Mycobiology
• /
• 제43권3호
• /
• pp.319-326
• /
• 2015

Fomes fomentarius is a fungus of the Polyporaceae family and is used in traditional oriental therapies. Although the anti-inflammatory activities of this species have been previously reported, the identity of the bioactive compounds responsible for this activity remains unknown. Here, we investigated whether methyl 9-oxo-(10E,12E)-octadecadienoate (FF-8) purified from F. fomentarius exerts anti-inflammatory activity in murine macrophages stimulated with lipopolysaccharide (LPS). FF-8 suppressed secretion of nitric oxide (NO) and prostaglandin $E_2$ through downregulation of inducible NO synthase and cyclooxygenase-2 expression induced by LPS. In addition, pretreatment of cells with FF-8 led to a reduction in levels of secreted inflammatory cytokines such as tumor necrosis factor-${\alpha}$ and interleukin-6 in macrophages stimulated with LPS. Conversely, FF-8 did not affect nuclear factor ${\kappa}B$, p38, c-Jun NH2-terminal kinase, and extracellular signal-regulated kinase pathways. Instead, FF-8 specifically interfered with signal transducer and activator of transcription 3 (STAT3) phosphorylation induced by LPS. Collectively, this study demonstrated that FF-8 purified from F. fomentarius suppresses inflammatory responses in macrophages stimulated with LPS by inhibiting STAT3 activation. Further studies will be required to elucidate the anti-inflammatory effect of FF-8 in vivo.

• 대한예방한의학회지
• /
• 제16권3호
• /
• pp.155-165
• /
• 2012

Objective : The object of this study is to confirm the immune enhancement effect of Rubus coreanus Miquel (RC) (30% EtOH extract) on RAW264.7 mouse macrophage cell line. Methods : RAW264.7 cells were treated with $10-500{\mu}g/mL$ RC for 24 hours. Cell viability was then measured using WST assays. Levels of intracellular NO and ROS were measured by Griess reagent and DCFH-DA staining respectively. Levels of iNOS and COX-2 mRNA was determined by RT-PCR. Secretion levels of IL-$1{\beta}$ and IL-6 cytokines were evaluated by sandwich ELISA assay. Western blot analysis was performed to measure the levels of intracellular molecules related to MAPKs pathways. Results : RC suppressed the growth of RAW264.7 cells. RC increased the production of NO and ROS. RC increased the mRNA and protein levels of COX-2 and iNOS. RC augmented the levels of secreted IL-$1{\beta}$ and IL-6 cytokines. RC increased MAPKs phosphorylation. Conclusion : In summary, our result shows that RC has inflammatory effect increasing the levels of NO, ROS and secreted cytokines and activating MAPKs. Hence, RC seems to have an immune enhancement effect.

• BMB Reports
• /
• 제51권12호
• /
• pp.654-659
• /
• 2018

Antioxidant 1 (ATOX1) protein has been reported to exhibit various protective functions, including antioxidant and chaperone. However, the effects of ATOX1 on the inflammatory response has not been fully elucidated. Thus, we prepared cell permeable Tat-ATOX1 and studied the effects on lipopolysaccharide (LPS)- and 12-O-tetradecanoyl phorbol-13-acetate (TPA)-induced inflammation. Experimental results showed that transduced Tat-ATOX1 protein significantly suppressed LPS-induced intracellular reactive oxygen species (ROS). Also, Tat-ATOX1 protein markedly inhibited LPS- and TPA-induced inflammatory responses by decreasing cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) and further inhibited phosphorylation of mitogen activated protein kinases (MAPKs; JNK, ERK and p38) and the nuclear factor-kappaB ($NF-{\kappa}B$) signaling pathway. These results indicate that the Tat-ATOX1 protein has a pivotal role in inflammation via inhibition of inflammatory responses, suggesting Tat-ATOX1 protein may offer a therapeutic strategy for inflammation.

• Journal of Applied Biological Chemistry
• /
• 제62권1호
• /
• pp.39-50
• /
• 2019

Mitogen-activated protein (MAP) kinases play an important role in cell growth and differentiation, as well as the modulation of proinflammatory cytokines. The objective of this study was to examine the increase in the anti-inflammatory effect of Gentiana scabra Bunge (GSB), due to bioconversion with the Aspergillus kawachii crude enzyme, via inhibition of the $NF-{\kappa}B$ signaling and MAP kinase pathways in RAW 264.7 cells. The expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 in RAW 264.7 cells treated with the GSB ethyl acetate fraction bioconverted with A. kawachii crude enzyme (GE-BA), was dramatically suppressed as compared to GSB ethyl acetate fraction non-bioconverted with the A. kawachii crude enzyme (GE-UA). The phosphorylation of p38, extracellular signal-regulated kinases, and inhibitory ${\kappa}B$ in RAW 264.7 cells treated with GE-BA was further suppressed, as compared to exposure to GE-UA. Moreover, the mRNA expression of interleukin 6, interleukin 1-beta, and tumor necrosis $factor-{\alpha}$ was further suppressed by GE-BA, compared to GE-UA. Similarly, anti-oxidant activities, such as 2,2-diphenyl-1-picrylhydrazyl hydrate and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) radical scavenging activity, of GE-BA were further increased compared to GE-UA. These observations demonstrate that the anti-oxidant and anti-inflammatory activities of GSB ethyl acetate fraction increases as a result from bioconversion with the A. kawachii crude enzyme.

• 대한본초학회지
• /
• 제37권6호
• /
• pp.19-28
• /
• 2022

Objectives : To develop natural ingredients that help prevent or treat anti-inflammatory-related diseases and use themas basic data, we investigated anti-inflammatory activity of Cynanchi Atrati Radix Et Rhizoma water extracts(CWE) in lipopolysaccharide(LPS)-induced murine macrophage cell line, RAW 264.7 cells. Methods : The cell viabilities were evaluated with RAW 264.7 cells. The production of nitric oxide(NO), prostaglandin E2(PGE2), pro-inflammatory cytokines such tumor necrotic factor(TNF)-α and interleukin(IL)-6 were assessed in LPS-induced RAW 264.7 cell treated with CWE. Furthermore, the protein expression of inducible nitric oxide synthase (iNOS), cyclooxygenase-2(COX-2), and mitogen-activated protein kinase(MAPK) were assessed by western blotting. Results : In RAW 264.7 cell, the cell viability by CWE treatment was more than 98.4% at a concentration of 100-400 ㎍/mL. At a concentration of 800 ug/ml of CWE, the cell viability was as low as 86%. At doses of 100, 200 and 400 ㎍/mL, CWE inhibited the production of NO, PGE2, TNF-𝛼 and IL-6 in a dose-dependent manner and also decreased the expression of iNOS and COX-2 from LPS-induced RAW 264.7 cells. In addition, CWE significantly inhibited the MAPK pathway including decreased the phosphorylation of the p38, c-Jun N-terminal kinase(JNK) and extracellular signal-regulated kinase(ERK1/2). Conclusions : Our study provides evidence that CWE inhibits the production of main pro-inflammatory molecules in LPS-induced RAW 264.7 cells via expression of p38, JNK, and ERK1/2 MAPK signaling pathways. Therefore, CWE is expected to be widely used as a natural ingredient for anti-inflammatory functional foods or pharmaceuticals in the future.

• Journal of Applied Biological Chemistry
• /
• 제65권1호
• /
• pp.33-41
• /
• 2022

Esculetin (also known as 6, 7-dihydroxycoumarin) a type of coumarin, has been exhibited anti-inflammatory and anti-aging effects. Biorenovation is the microbe-mediated enhancement of biological efficacies and structurally diversified compounds relative to their substrate compounds. The production of different kinds of esculetin derivatives using Bacillus sp. JD3-7 and their effects on lipopolysaccharide (LPS)-triggered inflammatory response in RAW 26.7 cells were assessed. One of the biorenovation products, identified as esculetin 6-O-phosphate (ESP), at concentrations of 1.25, 2.5, and 5 μM inhibited the LPS-stimulated production of inflammation markers of nitric oxide synthase 2 and cyclooxygenase 2 as well as their respective enzymatic reaction products of nitric oxide and prostaglandin E2 in the order of increasing concentrations (1.25, 2.5, and 5 μM). Additionally, ESP treatment suppressed the LPS-stimulated secretion of pro-inflammatory cytokines of interleukin (IL)-1β, IL-6, and tumor necrosis factor- α. Furthermore, these anti-inflammatory effect of ESP was associated with the downregulation of mitogen-activated protein kinase signaling, that is, extracellular signal-regulated kinase, c-Jun NH2-terminal kinase, and p38 mitogen-activated protein kinase signaling pathways. This study would therefore provide interesting insights into the biorenovation-assisted generation of a novel anti-inflammatory compound. ESP may be used to develop treatments for inflammatory disorders.

• Molecules and Cells
• /
• 제46권4호
• /
• pp.245-255
• /
• 2023

This study aimed to exploring the pathophysiological mechanism of 7α,25-dihydroxycholesterol (7α,25-DHC) in osteoarthritis (OA) pathogenesis. 7α,25-DHC accelerated the proteoglycan loss in ex vivo organ-cultured articular cartilage explant. It was mediated by the decreasing extracellular matrix major components, including aggrecan and type II collagen, and the increasing expression and activation of degenerative enzymes, including matrix metalloproteinase (MMP)-3 and -13, in chondrocytes cultured with 7α,25-DHC. Furthermore, 7α,25-DHC promoted caspase-dependent chondrocyte death via extrinsic and intrinsic pathways of apoptosis. Moreover, 7α,25-DHC upregulated the expression of inflammatory factors, including inducible nitric oxide synthase, cyclooxygenase-2, nitric oxide, and prostaglandin E₂, via the production of reactive oxygen species via increase of oxidative stress in chondrocytes. In addition, 7α,25-DHC upregulated the expression of autophagy biomarkers, including beclin-1 and microtubule-associated protein 1A/1B-light chain 3 via the modulation of p53-Akt-mTOR axis in chondrocytes. The expression of CYP7B1, caspase-3, and beclin-1 was elevated in the degenerative articular cartilage of mouse knee joint with OA. Taken together, our findings suggest that 7α,25-DHC is a pathophysiological risk factor of OA pathogenesis that is mediated a chondrocyte death via oxiapoptophagy, which is a mixed mode of apoptosis, oxidative stress, and autophagy.

• 생명과학회지
• /
• 제23권11호
• /
• pp.1397-1403
• /
• 2013

괴각(Fructus Sophorae)은 회화나무(Styphnolobium japonicum L.)의 열매를 건조한 것으로 전통 한의학에서 널리 사용되는 약재 중의 하나이다. 본 연구에서는 murine RAW 264.7 대식세포 모델을 이용하여 괴각 추출물 (Fructus Sophorae extracts, FSE)이 면역 조절능에 미치는 영향을 조사하였다. 이를 위한 대식세포 활성과 연관된 면역 반응 parameter로서 prostaglandin $E_2$ ($PGE_2$)와 tumor necrotic $factor-{\alpha}$ ($TNF-{\alpha}$)의 생성에 미치는 FSE의 영향을 조사하였다. 본 연구의 결과에 의하면 FSE는 대식세포의 활성을 유도하였고, $PGE_2$ 및 $TNF-{\alpha}$의 생성을 촉진하였으며, 이는 cyclooxygenase-2 (COX-2)와 $TNF-{\alpha}$ 유전자의 전사 및 번역 수준에서의 활성화와 연관성이 있었다. 또한 FSE 처리에 의하여 다양한 종류의 cytokine 발현의 증가를 cytokine array 분석을 통하여 확인하였으며, RAW 264.7 대식세포의 활성화에는 mitogen-activated protein kinases (MAPKs) 및 phosphatidylinositol-3-kinase (PI3K)/Akt 경로 활성화가 연관되어 있음을 알 수 있었다. 본 연구의 결과는 괴각 추출물이 면역 증강제로서의 개발 가능성이 매우 높음을 시사한다.