• The Korean Journal of Physiology and Pharmacology
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• v.5 no.1
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• pp.87-92
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• 2001

Carbon monoxide (CO) binds to soluble guanylate cyclase to lead its activation and elicits smooth muscle relaxation. The vascular tissues have a high capacity to produce CO, since heme oxygenase-2 (HO-2) is constitutively expressed in endothelial and smooth muscle cells, and HO-1 can be greatly up-regulated by oxidative stress. Moreover, the substrate of HO, heme, is readily available for catalysis in vascular tissue. Although the activation of heme oxygenase pathway under various stress conditions may provide a defence mechanism in compromised tissues, the specific role of HO-1-derived CO in the control of aortic contractility still remains to be elucidated. The present study was done to determine the effect of HO-1 induction on the aortic contractility. Thus, the effects of incubation of aortic tissue with S-nitroso-N-acetylpenicillamine (SNAP) for 1 hr on the aortic contractile response to phenylephrine were studied. The preincubation with SNAP resulted in depression of the vasoconstrictor response to phenylephrine. This effect was restored by HO inhibitor or methylene blue but not by NOS inhibitor. The attenuation of vascular reactivity by preincubation with SNAP was also revealed in endothelium-free rings. $AlF4^--evoked$ contraction in control did not differ from that in SNP-treated group. These results suggest that increased production of CO was responsible for the reduction of the contractile response to phenylephrine in aortic ring preincubated with SNAP and this effect of SNAP was independent on endothelium.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.3
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• pp.219-224
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• 2012

Understanding how the b-wave of the electroretinogram (ERG) is generated by full-field light stimulation is still a challenge in visual neuroscience. To understand more about the origin of the b-wave, we studied the contributions of gap junctions to the ERG b-wave. Many types of retinal neurons are connected to similar and different neighboring neurons through gap junctions. The photopic (cone-dominated) ERG, stimulated by a small light beam, was recorded from goldfish (Carassius auratus) using a corneal electrode. Data were obtained before and after intravitreal injection of agents into the eye under a photopic illumination level. Several agents were used to affect gap junctions, such as dopamine D1 and D2 receptor agonists and antagonists, a nitric oxide (NO) donor, a nitric oxide synthase (NOS) inhibitor, the gap junction blocker meclofenamic acid (MFA), and mixtures of these agents. The ERG b-waves, which were enhanced by MFA, sodium nitroprusside (SNP), SKF 38393, and sulpiride, remained following application of a further injection of a mixture with MFA. The ERG b-waves decreased following $N^G$-nitro-L-arginine methyl ester (L-NAME), SCH 23390, and quinpirole administration but were enhanced by further injection of a mixture with MFA. These results indicate that gap junction activity influences b-waves of the ERG related to NO and dopamine actions.

• Proceedings of the Korean Society of Toxicology Conference
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• 2002.11b
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• pp.143-143
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• 2002

Capsaicin (8-methyl-N-vanillyl-6-nonenamide), a pungent ingredient of hot chili peppers, has been reported to possess substantial anticarcinogenic and antimutagenic activities. In our previous study, we found that capsaicin (100 ${\mu}$M) induced significant inhibition of matrix metalloproteinase-2 activity by gelatin zymography, and that capsaicin (i.p., 2.5mg/kg) inhibited development of lung colonization (58%) in experimental lung metastasis assay.(omitted)

• Proceedings of the Korean Society of Applied Pharmacology
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• 1998.11a
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• pp.176-176
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• 1998

An enhanced formation of nitric oxide (NO) is an important mediator of hypotention, peripheral vasodilation and vascular hyporeactivity to vasoconstrictor agents in endotoxaemia. And tumor necrosis factor (TNF${\alpha}$), as a primary mediator of circulatory shock has been known to induce inducible nitric oxide synthase (i-NOS), leading to excessive production of NO. We isolated two sesquiterpene lactone compounds from Saussurea lappa and their structures were elucidated as dehydrocostus lactone and costunolide. These compounds inhibit the production of both NO and TNF${\alpha}$ by LPS (1 $\mu\textrm{g}$/$m\ell$)-activated Raw 264.7 cells. NO was measured spectropho-tometrically as nitrite by the Griess reagent and TNF${\alpha}$ by ELISA. Dehydrocostus lactone (IC$\sub$50/ : 3.0 ${\mu}$M) and costunolide (IC$\sub$50/ : 4.5 ${\mu}$M) inhibited the production of NO in LPS-activated Raw 264.7 cells by suppressing inducible nitric oxide synthase enzyme expression. These compounds also decreased the TNF${\alpha}$ levels in LPS-activated system in vitro and in vivo.

• Korean Journal of Plant Resources
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• v.35 no.6
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• pp.697-703
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• 2022

Under the COVID-19 pandemic, interest in immune enhancement is increasing. Although the immune-enhancing activity of plants of the genus Hibiscus has been reported, there is no study on the immune-enhancing activity of H. syriacus. Thus, in this study, we investigated the immune-enhancing activity of Hibiscus syriacus leaves (HSL) in mouse macrophages, RAW264.7 cells, and immunosuppressed mice. HSL increased the production of immunostimulatory factors such as nitric oxide (NO), inducible nitric oxide synthase (iNOS), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) and activated the phagocytosis in RAW264.7 cells. The HSL-mediated production of immunostimulatory factors was dependent on toll-like receptor 4 (TLR4), p38, and c-Jun N-terminal kinase (JNK) in RAW264.7 cells. In the immunosuppressed mouse model, HSL increased the spleen index, the levels of the cytokines, and the numbers of lymphocytes, neutrophils, and monocytes. Taken together, HSL may be considered to have immune-enhancing activity and be expected to be used as a potential immune-enhancing agent.

• CELLMED
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• v.13 no.6
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• pp.7.1-7.6
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• 2023

Raphanus sativus L. has been reported to have anti-inflammatory and anti-tumor activity. However, the anti-inflammatory effect and mechanism of action of the Raphanus sativus L. seeds (RSS) with or without oil are still unknown. This study was undertaken to investigate the in-vitro anti-inflammatory effect with or without oil in the RSS on RAW 264.7 cells stimulated by lipopolysaccharide (LPS). Results showed the suppressed LPS-induced secretion of pro-inflammatory mediators such as nitric oxide (NO), inflammatory cytokine (IL-6, TNF-α). Additionally, a decrease in protein expression of iNOS was observed, but nuclear translocation of NF-κB p65 was not inhibited. To elucidate the underlying mechanism of the anti-inflammatory effect of RSS, the involvement of mitogen-activated protein kinase (MAPK) signaling pathways was examined. We also found that RSS blocked LPS-induced phosphorylation of c-Jun N-terminal kinase/stress-activated protein kinase (JNK) signaling but did not affect the phosphorylation of p38 MAPK and extracellular signal-regulated kinase (ERK) 1/2. These results suggest that RSS may have potential as an anti-inflammatory agent through the inhibition of LPS-induced inflammatory cytokine production via regulation of the JNK pathway.

• Journal of Marine Bioscience and Biotechnology
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• v.15 no.1
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• pp.12-23
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• 2023

Sargassum horneri (SH), a brown macroalgae, has medicinal properties. The present study investigated the immune-enhancing effects of SH extract on peritoneal macrophages (PM). The SH significantly increased the production of tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and nitric oxide (NO) in PM. It was confirmed that SH significantly increased NO expression through the increase of iNOS protein expression, which is the up-regulation pathway. Additionally, it was determined if SH activates the mitogen-activated protein kinase (MAPK) pathway, an upper regulatory mechanism that influences TNF-α, IL-6, and NO expression. Consequently, SH significantly increased the phosphorylation of p38, extracellular signal-regulated kinases (ERK), and c-Jun N-terminal kinase (JNK), all of which are MAPK pathway proteins. Moreover, the immune-enhancing effects of SH on another macrophage cell line, bone marrow-derived macrophages were investigated. It was observed that SH significantly enhanced TNF-α, IL-6, and NO production. Overall, this study demonstrates the immune-enhancing effects of SH on macrophages via activated MAPK pathway. Therefore, it suggests that SH has the potential to improve immunological activity in various macrophage cell lines and can be useful as an immune-enhancing treatment.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.92-92
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• 2022

Under the COVID-19 pandemic, interest in immune enhancement is increasing. Although the immune-enhancing activity of plants of the genus Hibiscus has been reported, there is no study on the immune-enhancing activity of H. syriacus. Thus, in this study, we investigated the immune-enhancing activity of Hibiscus syriacus leaves (HSL) in mouse macrophages, RAW264.7 cells, and immunosuppressed mice. HSL increased the production of immunostimulatory factors such as nitric oxide (NO), inducible nitric oxide synthase (iNOS), interleukin-1β (IL-1β), and tumor necrosis factor-α (TNF-α) and activated the phagocytosis in RAW264.7 cells. The HSL-mediated production of immunostimulatory factors was dependent on toll-like receptor 4 (TLR4), p38, and c-Jun N-terminal kinase (JNK) in RAW264.7 cells. In the immunosuppressed mouse model, HSL increased the spleen index, the levels of the cytokines, and the numbers of lymphocytes, neutrophils, and monocytes. Taken together, HSL may be considered to have immune-enhancing activity and be expected to be used as a potential immune-enhancing agent.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.107-107
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• 2022

Scrophularia koraiensis Nakai is widely used to remedy fever, edema, and neuritis. S. koraiensis has harpagoside and angoroside C, these compounds have been reported to alleviate inflammation, rheumatic diseases, and analgesic stimulation. We evaluated the anti-inflammatory effects of the ethanol extract of S. koraiensis (SKE) in lipopolysaccharides (LPS)-induced macrophages. At cellular levels, SKE decreased the production of nitric oxide (NO), the expression of inducible nitric oxide synthase (iNOS), and cytokines (IL-1b, TNF-a, and IL-6) under the LPS stimulation. SKE inhibited the phosphorylation of nuclear transcription factor-kappa B (NF-κB) p65 and its inhibitor (IκB-α). In addition, SKE suppressed the phosphorylation of extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), and p38 in the mitogen-activated protein kinase (MAPK) pathway. In conclusion, SKE could be considered a potential resource for attenuating inflammation response and it may be utilized in the material for cosmetics, food additives, and tea.

• Journal of Mushroom
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• v.21 no.4
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• pp.215-221
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• 2023

Owing to its diverse range of bioactive compounds, Ganoderma lucidumhas garnered significant research attention for health promotion and disease prevention. Ganodermanondiol, which has a triterpenoid structure, is one of the major active compounds of G. lucidum. In the present study, the anti-inflammatory effects of ganodermanondiol were investigated to evaluate its usefulness as a functional ingredient. Ganodermanondiol (0.5-2 ㎍/mL) significantly inhibited the production of nitric oxide (NO), the expression of the cytokines tumor necrosis factor (TNF)??and interleukin 6 (IL-6), and the expression of cyclooxygenase (COX)-2 and inducible nitric oxide synthase (iNOS) in lipopolysaccharide-induced RAW 264.7 (murine macrophage) cells. Ganodermanondiol (0.5-2 ㎍/mL) also inhibited the phosphorylation of mitogen-activated protein kinase (MAPK) signal molecules, including p38 and c-Jun N-terminal protein kinase (JNK) in RAW 264.7 cells. Ganodermanondiol significantly inhibited the essential factors involved in the inflammatory responses of RAW 264.7 cells and would, therefore, serve as a potential prophylactic and therapeutic agent for immune-related diseases.