scholarly journals Bioactive Constituents from the Roots of Eurycoma longifolia

Molecules ◽  
2019 ◽  
Vol 24 (17) ◽  
pp. 3157 ◽  
Author(s):  
Jingya Ruan ◽  
Zheng Li ◽  
Ying Zhang ◽  
Yue Chen ◽  
Mengyang Liu ◽  
...  

Four new phenolic components, eurylophenolosides A (1) and B (2), eurylolignanosides A (3) and B (4), along with twelve known compounds were isolated from the roots of Eurycoma longifolia Jack. The structure of these components was elucidated by using various spectral techniques and chemical reactions. Among the known isolates, syringaldehyde (12), 3-chloro-4-hydroxybenzoic acid (13), 3-chloro-4-hydroxyl benzoic acid-4-O-β-d-glucopyranoside (14), and isotachioside (15) were isolated from the Eurycoma genus for the first time. Further, the NMR data of 14 was reported here firstly. Meanwhile, the nitric oxide (NO) inhibitory activities of all compounds were examined in lipopolysaccharide (LPS)-stimulated RAW264.7 cells at 40 μM. As results, piscidinol A (6), 24-epi-piscidinol A (7), bourjotinolone A (10), and scopoletin (16) were found to play important role in suppressing NO levels without cytotoxicity. Furthermore, the Western blot method was used to investigate the mechanism of compounds 6, 7, 10, and 16 by analysing the level of inflammation related proteins, such as inducible nitric oxide synthase (iNOS), interleukin-6 (IL-6), and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) in LPS-stimulated RAW264.7 cells. Consequently, compounds 6, 7, 10, and 16 were found to significantly inhibit LPS-induced protein expression of IL-6, NF-κB and iNOS in NF-κB signaling pathway. Moreover, it was found that the protein expression inhibitory effects of 6, 7, and 16 exhibited in a dose-dependent manner. The mechanism may be related to the inhibition of the iNOS expressions through suppressing the IL-6-induced NF-κB pathway.

2020 ◽  
Vol 85 (4) ◽  
pp. 882-889
Author(s):  
Yan Liang ◽  
Shijiao Zha ◽  
Masanobu Tentaku ◽  
Takasi Okimura ◽  
Zedong Jiang ◽  
...  

ABSTRACT In this study, we found that a sulfated polysaccharide isolated from the brown alga Ascophyllum nodosum, ascophyllan, showed suppressive effects on stimulated RAW264.7 cells. Ascophyllan significantly inhibited expression of inducible nitric oxide synthase mRNA and excessive production of nitric oxide (NO) in lipopolysaccharide (LPS)-stimulated RAW264.7 cells in a dose-dependent manner without affecting the viability of RAW264.7 cells. Ascophyllan also reduced the elevated level of intracellular reactive oxygen species (ROS) in LPS-stimulated RAW264.7 cells. Furthermore, preincubation with ascophyllan resulted in concentration-dependent decrease in ROS production in phorbol 12-myristate-13-acetate-stimulated RAW264.7 cells. Our results suggest that ascophyllan can exhibit anti-inflammatory effects on stimulated macrophages mainly through the attenuation of NO and ROS productions.


Molecules ◽  
2020 ◽  
Vol 25 (16) ◽  
pp. 3573
Author(s):  
Lian-Chun Li ◽  
Zheng-Hong Pan ◽  
De-Sheng Ning ◽  
Yu-Xia Fu

Simonsinol is a natural sesqui-neolignan firstly isolated from the bark of Illicium simonsii. In this study, the anti-inflammatory activity of simonsinol was investigated with a lipopolysaccharide (LPS)-stimulated murine macrophages RAW264.7 cells model. The results demonstrated that simonsinol could antagonize the effect of LPS on morphological changes of RAW264.7 cells, and decrease the production of nitric oxide (NO), tumor necrosis factor α (TNF-α), and interleukin 6 (IL-6) in LPS-stimulated RAW264.7 cells, as determined by Griess assay and enzyme-linked immunosorbent assay (ELISA). Furthermore, simonsinol could downregulate transcription of inducible nitric oxide synthase (iNOS), TNF-α, and IL-6 as measured by reverse transcription polymerase chain reaction (RT-PCR), and inhibit phosphorylation of the alpha inhibitor of NF-κB (IκBα) as assayed by Western blot. In conclusion, these data demonstrate that simonsinol could inhibit inflammation response in LPS-stimulated RAW264.7 cells through the inactivation of the nuclear transcription factor kappa-B (NF-κB) signaling pathway.


Biomedicines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 420
Author(s):  
Su-Jung Hwang ◽  
Ye-Seul Song ◽  
Hyo-Jong Lee

Kushen (Radix Sophorae flavescentis) is used to treat ulcerative colitis, tumors, and pruritus. Recently, phaseolin, formononetin, matrine, luteolin, and quercetin, through a network pharmacology approach, were tentatively identified as five bioactive constituents responsible for the anti-inflammatory effects of S. flavescentis. However, the role of phaseolin (one of the primary components of S. flavescentis) in the direct regulation of inflammation and inflammatory processes is not well known. In this study, the beneficial role of phaseolin against inflammation was explored in lipopolysaccharide (LPS)-induced inflammation models of RAW 264.7 macrophages and zebrafish larvae. Phaseolin inhibited LPS-mediated production of nitric oxide (NO) and the expression of inducible nitric oxide synthase (iNOS), without affecting cell viability. In addition, phaseolin suppressed pro-inflammatory mediators such as cyclooxygenase 2 (COX-2), interleukin-1β (IL-1β), tumor necrosis factor α (TNF-α), monocyte chemoattractant protein-1 (MCP-1), and interleukin-6 (IL-6) in a dose-dependent manner. Furthermore, phaseolin reduced matrix metalloproteinase (MMP) activity as well as macrophage adhesion in vitro and the recruitment of leukocytes in vivo by downregulating Ninjurin 1 (Ninj1), an adhesion molecule. Finally, phaseolin inhibited the nuclear translocation of nuclear factor-kappa B (NF-κB). In view of the above, our results suggest that phaseolin could be a potential therapeutic candidate for the management of inflammation.


1998 ◽  
Vol 274 (1) ◽  
pp. C245-C252 ◽  
Author(s):  
Junsuke Igarashi ◽  
Masashi Nishida ◽  
Shiro Hoshida ◽  
Nobushige Yamashita ◽  
Hiroaki Kosaka ◽  
...  

The effects of nitric oxide (NO) produced by cardiac inducible NO synthase (iNOS) on myocardial injury after oxidative stress were examined. Interleukin-1β induced cultured rat neonatal cardiac myocytes to express iNOS. After induction of iNOS,l-arginine enhanced NO production in a concentration-dependent manner. Glutathione peroxidase (GPX) activity in myocytes was attenuated by elevated iNOS activity and by an NO donor, S-nitroso- N-acetyl-penicillamine (SNAP). Although NO production by iNOS did not induce myocardial injury, NO augmented release of lactate dehydrogenase from myocyte cultures after addition of H2O2(0.1 mM, 1 h). Inhibition of iNOS with Nω-nitro-l-arginine methyl ester ameliorated the effects of NO-enhancing treatments on myocardial injury and GPX activity. SNAP augmented the myocardial injury induced by H2O2. Inhibition of GPX activity with antisense oligodeoxyribonucleotide for GPX mRNA increased myocardial injury by H2O2. Results suggest that the induction of cardiac iNOS promotes myocardial injury due to oxidative stress via inactivation of the intrinsic antioxidant enzyme, GPX.


2000 ◽  
Vol 68 (12) ◽  
pp. 7087-7093 ◽  
Author(s):  
Y.-H. Li ◽  
Z.-Q. Yan ◽  
J. Skov Jensen ◽  
K. Tullus ◽  
A. Brauner

ABSTRACT Chronic lung disease (CLD) of prematurity is an inflammatory disease with a multifactorial etiology. The importance ofUreaplasma urealyticum in the development of CLD is debated, and steroids produce some improvement in neonates with this disease. In the present study, the capability of U. urealyticum to stimulate rat alveolar macrophages to produce nitric oxide (NO), express inducible nitric oxide synthase (iNOS), and activate nuclear factor κB (NF-κB) in vitro was characterized. The effect of NO on the growth of U. urealyticum was also investigated. In addition, the impact of dexamethasone and budesonide on these processes was examined. We found that U. urealyticum antigen (≥4 × 107 color-changing units/ml) stimulated alveolar macrophages to produce NO in a dose- and time-dependent manner (P < 0.05). This effect was further enhanced by gamma interferon (100 IU/ml; P < 0.05) but was attenuated by budesonide and dexamethasone (10−4 to 10−6 M) (P < 0.05). The mRNA and protein levels of iNOS were also induced in response to U. urealyticum and inhibited by steroids.U. urealyticum antigen triggered NF-κB activation, a possible mechanism for the induced iNOS expression, which also was inhibited by steroids. NO induced by U. urealyticum caused a sixfold reduction of its own growth after infection for 10 h. Our findings imply that U. urealyticum may be an important factor in the development of CLD. The host defense response againstU. urealyticum infection may also be influenced by NO. The down-regulatory effect of steroids on NF-κB activation, iNOS expression, and NO production might partly explain the beneficial effect of steroids in neonates with CLD.


2021 ◽  
Vol 24 (3) ◽  
Author(s):  
Hirokazu Hattori ◽  
Kazuki Takaoka ◽  
Miho Ueta ◽  
Masayuki Oshitani ◽  
Joji Tamaoka ◽  
...  

2010 ◽  
Vol 30 (4) ◽  
pp. 233-241 ◽  
Author(s):  
Kai Zhao ◽  
Zhen Huang ◽  
Hongling Lu ◽  
Juefei Zhou ◽  
Taotao Wei

Macrophages produce a large volume of ROS (reactive oxygen species) through respiratory burst. However, the influence of iNOS [inducible NOS (nitric oxide synthase)] activation on ROS production remains unclear. In the present study, the kinetic generation of ROS in RAW264.7 murine macrophages was monitored by chemiluminescence. PMA induces a robust chemiluminescence in RAW264.7 cells, suggesting PKC (protein kinase C)-related assembly and activation of NOX (NADPH oxidase). The effects of iNOS induction on ROS production were examined. Induction of iNOS expression in RAW264.7 cells with LPS (lipopolysaccharide; 1 μg/ml) causes a significant increase in PMA-induced chemiluminescence, which could be enhanced by the NOS substrate, L-arginine, and could be abolished by the NOS inhibitor, L-NNA (NG-nitro-L-arginine). Further experiments reveal that induction of iNOS expression enhances the PMA-stimulated phosphorylation of the p47phox subunit of NOX, and promotes the relocalization of cytosolic p47phox and p67phox subunits to the membrane. Inhibition of PKCζ by its myristoylated pseudosubstrate significantly decreased the PMA-stimulated phosphorylation of the p47phox in LPS-pretreated cells, suggesting that PKCζ is involved in the iNOS-dependent assembly and activation of NOX. Taken together, the present study suggests that the induction of iNOS upregulates the PMA-induced assembly of NOX and leads to the enhanced production of ROS via a PKCζ-dependent mechanism.


2004 ◽  
Vol 14 (6) ◽  
pp. 411-417 ◽  
Author(s):  
Ping Liu ◽  
Catherine M. Gliddon ◽  
Libby Lindsay ◽  
Cynthia L. Darlington ◽  
Paul F. Smith

Previous studies have shown that peripheral vestibular damage causes long-term neurochemical changes in the hippocampus which may be related to spatial memory deficits. Since recent studies have also demonstrated deficits in non-spatial object recognition memory following vestibular lesions, the aim of the present study was to extend these investigations into the perirhinal cortex (PRC), which is known to be important for object recognition, and the related entorhinal cortex (EC). We examined the effects of unilateral vestibular deafferentation (UVD) on the expression of four enzymes associated with neuronal plasticity, neuronal nitric oxide synthase (nNOS), endothelial nitric oxide synthase (eNOS), arginase I and arginase II (AI and II), in the rat EC and PRC using Western blotting. Tissue was collected at 10 hs, 50 hs and 2 weeks post-UVD. In the EC and PRC, nNOS protein expression decreased on the contralateral side at 2 weeks post-UVD but not before. At the same time, eNOS protein expression increased in both regions on the contralateral side. In the EC, AII protein expression increased on the ipsilateral side at 2 weeks post-UVD. In the PRC, AI increased and decreased on the contralateral and ipsilateral sides (respectively) at 2 weeks post-UVD. AII showed a bilateral increase in the PRC at 2 weeks post-UVD. These results demonstrate changes in NOS and arginase protein expression in the PRC and EC following UVD, which are unlikely to be due to the initial severity of the vestibular syndrome because they develop well after vestibular compensation has taken place. Neurochemical changes in these regions of the medial temporal lobe may be implicated in the development of object recognition deficits that contribute to cognitive dysfunction following peripheral vestibular damage.


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