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Lauri Rautkari - One of the best experts on this subject based on the ideXlab platform.
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inhibitory effects of scots pine heartwood extractives on enzymatic holocellulose hydrolysis by wood decaying fungi
International Biodeterioration & Biodegradation, 2018Co-Authors: Tiina Belt, Filip Mollerup, Tuomas Hanninen, Lauri RautkariAbstract:Abstract The heartwood of Scots pine contains extractives that protect it against wood decaying fungi. Pine extractives such as Pinosylvins are fungicidal compounds, but they may also have other mechanisms of action. This experiment investigated whether Pinosylvins and other heartwood extractives can act as inhibitors of holocellulose hydrolysis, similarly to many other biomass-derived phenolic compounds. The inhibitory properties of extractives were studied against enzymes secreted by a brown rot (Coniophora puteana) and a white rot fungus (Trametes versicolor), as well as against a commercial Trichoderma reesei enzyme cocktail. The extractives were studied as wood-free extracts and extractives-containing wood powders. In all experiments, the behaviour of the white rot differed from that of the other two. The white rot hydrolases were strongly inhibited and deactivated by extractives, particularly Pinosylvins, whereas the others showed only mild or moderate inhibition and no deactivation. The white rot enzymes seemed to modify the Pinosylvins, with further studies suggesting that the modified Pinosylvins may form complexes with enzymes and cause their deactivation. These results suggest that pine heartwood extractives have potential to contribute to decay resistance as hydrolase inhibitors but only when the fungus produces enzymes capable of modifying the extractives.
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cellular level distributions of scots pine heartwood and knot heartwood extractives revealed by raman spectroscopy imaging
Industrial Crops and Products, 2017Co-Authors: Tiina Belt, Tuomas Hanninen, Tobias Keplinger, Lauri RautkariAbstract:Abstract Wood extractives are biologically active secondary metabolites that help protect wood and wood products from decay and other forms of biological attack. Despite the influence of distribution on their ability to protect wood, very few studies have investigated the distributions of extractives on a cellular level. In this paper, the distributions of extractives were studied in Scots pine (Pinus sylvestris L.) heartwood (HW) and knot heartwood by confocal Raman spectroscopy imaging. Pinosylvins, the antifungal phenolic extractives of pine, were found to be present in the cell walls, middle lamella, and lumina of tracheids. Their distribution suggested the existence of two different mechanisms of deposition and revealed similarities to the distribution of lignin. The potential binding of Pinosylvins to lignin and their relatively low concentration in HW cell walls could explain why Scots pine HW is, on average, only moderately resistant to decay. Resin acids, the most abundant group of extractives in pine, were detected only within the lumina of tracheids and ray cells, where they may contribute to the reduced permeability of HW. The extractives distributions presented here help us understand the properties of HW and provide a deeper understanding of the origins of natural durability, which is of value in the current efforts to develop more environmentally friendly means of wood protection.
Tiina Belt - One of the best experts on this subject based on the ideXlab platform.
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inhibitory effects of scots pine heartwood extractives on enzymatic holocellulose hydrolysis by wood decaying fungi
International Biodeterioration & Biodegradation, 2018Co-Authors: Tiina Belt, Filip Mollerup, Tuomas Hanninen, Lauri RautkariAbstract:Abstract The heartwood of Scots pine contains extractives that protect it against wood decaying fungi. Pine extractives such as Pinosylvins are fungicidal compounds, but they may also have other mechanisms of action. This experiment investigated whether Pinosylvins and other heartwood extractives can act as inhibitors of holocellulose hydrolysis, similarly to many other biomass-derived phenolic compounds. The inhibitory properties of extractives were studied against enzymes secreted by a brown rot (Coniophora puteana) and a white rot fungus (Trametes versicolor), as well as against a commercial Trichoderma reesei enzyme cocktail. The extractives were studied as wood-free extracts and extractives-containing wood powders. In all experiments, the behaviour of the white rot differed from that of the other two. The white rot hydrolases were strongly inhibited and deactivated by extractives, particularly Pinosylvins, whereas the others showed only mild or moderate inhibition and no deactivation. The white rot enzymes seemed to modify the Pinosylvins, with further studies suggesting that the modified Pinosylvins may form complexes with enzymes and cause their deactivation. These results suggest that pine heartwood extractives have potential to contribute to decay resistance as hydrolase inhibitors but only when the fungus produces enzymes capable of modifying the extractives.
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cellular level distributions of scots pine heartwood and knot heartwood extractives revealed by raman spectroscopy imaging
Industrial Crops and Products, 2017Co-Authors: Tiina Belt, Tuomas Hanninen, Tobias Keplinger, Lauri RautkariAbstract:Abstract Wood extractives are biologically active secondary metabolites that help protect wood and wood products from decay and other forms of biological attack. Despite the influence of distribution on their ability to protect wood, very few studies have investigated the distributions of extractives on a cellular level. In this paper, the distributions of extractives were studied in Scots pine (Pinus sylvestris L.) heartwood (HW) and knot heartwood by confocal Raman spectroscopy imaging. Pinosylvins, the antifungal phenolic extractives of pine, were found to be present in the cell walls, middle lamella, and lumina of tracheids. Their distribution suggested the existence of two different mechanisms of deposition and revealed similarities to the distribution of lignin. The potential binding of Pinosylvins to lignin and their relatively low concentration in HW cell walls could explain why Scots pine HW is, on average, only moderately resistant to decay. Resin acids, the most abundant group of extractives in pine, were detected only within the lumina of tracheids and ray cells, where they may contribute to the reduced permeability of HW. The extractives distributions presented here help us understand the properties of HW and provide a deeper understanding of the origins of natural durability, which is of value in the current efforts to develop more environmentally friendly means of wood protection.
Sang Kook Lee - One of the best experts on this subject based on the ideXlab platform.
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suppression of src erk and gsk 3 β catenin signaling by Pinosylvin inhibits the growth of human colorectal cancer cells
Food and Chemical Toxicology, 2013Co-Authors: Eunjung Park, Yonghyun Ahn, Hyen Joo Park, Hwajin Chung, Gi Dae Kim, Sang Kook LeeAbstract:Abstract Pinosylvin, a naturally occurring trans-stilbenoid mainly found in Pinus species, has exhibited a potential cancer chemopreventive activity. However, the growth inhibitory activity against cancer cells and the underlying molecular mechanisms remain to be elucidated. Therefore, the anti-proliferative activity of Pinosylvin was investigated in human colorectal HCT 116 cancer cells. Pinosylvin inhibited the proliferation of HCT 116 cells by arresting transition of cell cycle from G1 to S phase along with the downregulation of cyclin D1, cyclin E, cyclin A, cyclin dependent kinase 2 (CDK2), CDK4, c-Myc, and retinoblastoma protein (pRb), and the upregulation of p21WAF1/CIP1 and p53. Pinosylvin was also found to attenuate the activation of proteins involved in focal adhesion kinase (FAK)/c-Src/extracellular signal-regulated kinase (ERK) signaling, and phosphoinositide 3-kinase (PI3K)/Akt/ glycogen synthase kinase 3β (GSK-3β) signaling pathway. Subsequently, Pinosylvin suppressed the nuclear translocation of β-catenin, one of downstream molecules of PI3K/Akt/GSK-3β signaling, and these events led to the sequential downregulation of β-catenin-mediated transcription of target genes including BMP4, ID2, survivin, cyclin D1, MMP7, and c-Myc. These findings demonstrate that the anti-proliferative activity of Pinosylvin might be associated with the cell cycle arrest and downregulation of cell proliferation regulating signaling pathways in human colorectal cancer cells.
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antimetastatic activity of Pinosylvin a natural stilbenoid is associated with the suppression of matrix metalloproteinases
Journal of Nutritional Biochemistry, 2012Co-Authors: Eunjung Park, Jaeho Pyee, Yonghyun Ahn, Hyen Joo Park, Hwajin Chung, Hyeyoung Min, Jiyoung Hong, Youjin Kang, Yoonho Shin, Sang Kook LeeAbstract:Metastasis is a major cause of death in cancer patients. Our previous studies showed that Pinosylvin, a naturally occurring trans-stilbenoid mainly found in Pinus species, exhibited a potential cancer chemopreventive activity and also inhibited the growth of various human cancer cell lines via the regulation of cell cycle progression. In this study, we further evaluated the potential antimetastatic activity of Pinosylvin in in vitro and in vivo models. Pinosylvin suppressed the expression of matrix metalloproteinase (MMP)-2, MMP-9 and membrane type 1-MMP in cultured human fibrosarcoma HT1080 cells. We also found that Pinosylvin inhibited the migration of HT1080 cells in colony dispersion and wound healing assay systems. In in vivo spontaneous pulmonary metastasis model employing intravenously injected CT26 mouse colon cancer cells in Balb/c mice, Pinosylvin (10 mg/kg body weight, intraperitoneal administration) significantly inhibited the formation of tumor nodules and tumor weight in lung tissues. The analysis of tumor in lung tissues indicated that the antimetastatic effect of Pinosylvin coincided with the down-regulation of MMP-9 and cyclooxygenase-2 expression, and phosphorylation of ERK1/2 and Akt. These data suggest that Pinosylvin might be an effective inhibitor of tumor cell metastasis via modulation of MMPs.
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Pinosylvin suppresses lps stimulated inducible nitric oxide synthase expression via the myd88 independent but trif dependent downregulation of irf 3 signaling pathway in mouse macrophage cells
Cellular Physiology and Biochemistry, 2011Co-Authors: Eunjung Park, Jaeho Pyee, Yonghyun Ahn, Hwajin Chung, Hyeyoung Min, Sang Kook LeeAbstract:Since inhibitors of inducible nitric oxide synthase (iNOS) have been considered as potential anti-inflammatory and cancer chemopreventive agents, we have evaluated the inhibitory effects on the production of nitric oxide (NO) in lipopolysaccharide (LPS)-stimulated murine macrophage RAW 264.7 cells with natural and synthetic compounds. Pinosylvin (3,5-dihydroxy-trans-stilbene), a stilbenoid mainly found in heartwood of Pinus sylvestris, exhibited the inhibition of iNOS protein and mRNA expression. The plausible mechanisms of Pinosylvin on the suppression of iNOS gene expression were found to be associated with the downregulation of interferon regulatory factor 3 (IRF-3) and interferon-β (IFN-β) expression, which are related to Toll/IL-1 receptor domain-containing adapter inducing interferon-β (TRIF)-mediated signaling. Decreased IFN-β expression suppressed a phosphorylation of JAK kinase, and subsequently, the phosphorylation of signal transducer and activator of transcription-1, one of the iNOS transcriptional activators, was inhibited by Pinosylvin. In addition, the suppression of poly(I:C)-induced iNOS expression, and the attenuation of iNOS expression under the IRF-3 gene knock-down condition also confirmed that Pinosylvin affects TRIF pathway. These findings demonstrate that the suppression of LPS-induced iNOS expression by Pinosylvin is associated with the regulation of MyD88-independent, but TRIF-mediated signaling pathway.
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suppressive effects of Pinosylvin a natural stilbenoid on cyclooxygenase 2 and inducible nitric oxide synthase and the growth inhibition of cancer cells
Cancer Research, 2005Co-Authors: Eunjung Park, Jaeho Pyee, Yonghyun Ahn, Hyen Joo Park, Hwajin Chung, Hyeyoung Min, Jiyoung Hong, Youjin Kang, Inkyung Bae, Sang Kook LeeAbstract:748 Pinosylvin (3,5-dihydroxy- trans -stilbene), one of the naturally occurring resveratrol analog found in heartwood and leaves of Pinus species, is a phytoalexin with antioxidant, antifungal, algicidal and nematocidal activities. Based on anti-inflammatory and chemopreventive activities of resveratrol, we have evaluated the effects of Pinosylvin on cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS) activities in lipopolysaccharide (LPS)-stimulated RAW 264.7 mouse macrophage cells by measuring the production of prostaglandin E 2 (PGE 2 ) and nitric oxide (NO). As a result, Pinosylvin exhibited the inhibitory activities in both PGE 2 and NO productions in a dose dependent manner. To elucidate the inhibitory mechanism of Pinosylvin on COX-2 and iNOS expression, Western blot analysis and reverse transcription-polymerase chain reaction (RT-PCR) were performed. Pinosylvin suppressed COX-2 and iNOS protein and gene expression. Further study revealed that Pinosylvin inhibited NF-κB-DNA binding via the inhibition of IκB-α degradation. In addition, the growth inhibitory effects of Pinosylvin against human cancer cells were investigated. Pinosylvin inhibited the growth of HCT116 human colon cancer cells with an IC 50 value of 60 μM by MTT assay at 72 hr incubation. Cell cycle distribution treated by Pinosylvin (60 μM) exhibited G 0 /G 1 phase arrest. Checkpoint proteins of cyclin D1, cdk4 and proliferating cell nuclear antigen (PCNA) related to G 0 /G 1 phase were down-regulated by Pinosylvin. Taken together, Pinosylvin, a natural stilbenoid, might be a new candidate for a potential cancer chemopreventive agent.
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antibacterial and antifungal activity of Pinosylvin a constituent of pine
Fitoterapia, 2005Co-Authors: Sang Kook Lee, Eunjung Park, H J Lee, H Y Min, K M Lee, Y H Ahn, Y J Cho, Jaeho PyeeAbstract:The antibacterial and antifungal activities of Pinosylvin (3,5-dihydroxy-trans-stilbene), a constituent of pine, were studied and compared with those of resveratrol (3,5,4'-trihydroxy-trans-stilbene). Pinosylvin exhibited more potent growth inhibitory activity against Candida albicans and Saccharomyces cerevisiae.
Joachim Schroder - One of the best experts on this subject based on the ideXlab platform.
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molecular and enzymatic characterization of two stilbene synthases from eastern white pine pinus strobus a single arg his difference determines the activity and the ph dependence of the enzymes
FEBS Letters, 1995Co-Authors: Sigrid Raiber, Gudrun Schroder, Joachim SchroderAbstract:Pinus strobus (Eastern white pine) contains stilbenes biosynthetically derived from cinnamoyl-CoA (Pinosylvin) or dihydrocinnamoyl-CoA (dihydroPinosylvin). We screened a P. strobus cDNA library with a stilbene synthase (STS) probe from Pinus sylvestris. The eight isolated cDNAs represented two closely related STS genes with five amino acid differences in the proteins. The enzyme properties were investigated after heterologous expression in Escherichia coli. Both proteins preferred cinnamoyl-CoA against dihydrocinnamoyl-CoA and thus represented Pinosylvin synthases. Otherwise they revealed large differences. STS1 had only 3–5% of the activity of STS2, its pH optimum was shifted to lower values (pH 6), and it synthesized with cinnamoyl-CoA a second unknown product. Site-directed mutagenesis demonstrated that a single Arg-to-His exchange in STS1 was responsible for all of the differences. The proton acceptor properties of His are discussed as the reason for the properties of STS1.
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molecular analysis of chalcone and dihydroPinosylvin synthase from scots pine pinus sylvestris and differential regulation of these and related enzyme activities in stressed plants
Plant Molecular Biology, 1992Co-Authors: Judith Fliegmann, Gudrun Schroder, Sigrid Schanz, Lothar Britsch, Joachim SchroderAbstract:Chalcone synthase (CHS) and stilbene synthase (STS) are closely related polyketide synthases which are key enzymes in the biosynthesis of flavonoids and stilbenes. Scots pine (Pinus sylvestris) is an interesting plant for a direct comparison of the enzymes. It not only contains the usual flavonoids, but also an unusual chalcone derivative (pinocembrin), and it synthesizes stilbenes of the Pinosylvin type. We analysed a CHS and a STS by molecular cloning and functional expression in Escherichia coli. The CHS was active not only with 4-coumaroyl-CoA (to naringenin chalcone), but also with cinnamoyl-CoA (leading to pinocembrin). The STS was identified as dihydroPinosylvin synthase, because it preferred dihydrocinnamoyl-CoA to cinnamoyl-CoA. The protein deviated in 47 positions from the CHS consensus. It had 73.2% identity with the CHS from P. sylvestris and only 65.3% with a STS from peanut (Arachis hypogaea). We also investigated the regulation of both enzyme types in P. sylvestris plantlets exposed to stress. CHS was present in non-stressed plantlets, and induction led to a transient increase with a peak after 16 h. STS1 type activities were regulated differently and were absent in non-stressed plantlets. Increases were observed after a lag period of at least 6 h, and highest activities were obtained after 30 h. The analysis of the reactions in the plant extracts and the substrate specificity of the cloned STS indicate that the plants contain at least two different types of STS: the cloned dihydroPinosylvin synthase and a Pinosylvin synthase which preferentially utilizes cinnamoyl-CoA as substrate.
Eeva Moilanen - One of the best experts on this subject based on the ideXlab platform.
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Pinosylvin shifts macrophage polarization to support resolution of inflammation
Molecules, 2021Co-Authors: Konsta Kivimaki, Mari Hämäläinen, Tiina Leppänen, Katriina Vuolteenaho, Eeva MoilanenAbstract:Pinosylvin is a natural stilbenoid found particularly in Scots pine. Stilbenoids are a group of phenolic compounds identified as protective agents against pathogens for many plants. Stilbenoids also possess health-promoting properties in humans; for instance, they are anti-inflammatory through their suppressing action on proinflammatory M1-type macrophage activation. Macrophages respond to environmental changes by polarizing towards proinflammatory M1 phenotype in infection and inflammatory diseases, or towards anti-inflammatory M2 phenotype, mediating resolution of inflammation and repair. In the present study, we investigated the effects of Pinosylvin on M2-type macrophage activation, aiming to test the hypothesis that Pinosylvin could polarize macrophages from M1 to M2 phenotype to support resolution of inflammation. We used lipopolysaccharide (LPS) to induce M1 phenotype and interleukin-4 (IL-4) to induce M2 phenotype in J774 murine and U937 human macrophages, and we measured expression of M1 and M2-markers. Interestingly, along with inhibiting the expression of M1-type markers, Pinosylvin had an enhancing effect on the M2-type activation, shown as an increased expression of arginase-1 (Arg-1) and mannose receptor C type 1 (MRC1) in murine macrophages, and C-C motif chemokine ligands 17 and 26 (CCL17 and CCL26) in human macrophages. In IL-4-treated macrophages, Pinosylvin enhanced PPAR-γ expression but had no effect on STAT6 phosphorylation. The results show, for the first time, that Pinosylvin shifts macrophage polarization from the pro-inflammatory M1 phenotype towards M2 phenotype, supporting resolution of inflammation and repair.
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IL-6 in Osteoarthritis: Effects of Pine Stilbenoids.
Molecules (Basel Switzerland), 2018Co-Authors: Mirka Laavola, Mari Hämäläinen, Tiina Leppänen, Katriina Vuolteenaho, Teemu Moilanen, Riina Nieminen, Eeva MoilanenAbstract:Interleukin-6 (IL-6) is involved in the pathogenesis of various inflammatory diseases, like rheumatoid arthritis (RA). In the present study, we investigated the role of IL-6 in osteoarthritis (OA) patients and the effects of the stilbenoids monomethyl Pinosylvin and Pinosylvin on the expression of the cartilage matrix components aggrecan and collagen II and the inflammatory cytokine IL-6 in human OA chondrocytes. Synovial fluid and plasma samples were obtained from 100 patients with severe OA [BMI 29.7 (8.3) kg/m2, age 72 (14) years, median (IQR); 62/38 females/males] undergoing total knee replacement surgery. IL-6 and matrix metalloproteinase (MMP) concentrations in synovial fluid and plasma were measured by immunoassay. The effects of Pinosylvin on the expression of IL-6, aggrecan, and collagen II were studied in primary cultures of human OA chondrocytes. IL-6 levels in synovial fluid from OA patients [119.8 (193.5) pg/mL, median (IQR)] were significantly increased as compared to the plasma levels [3.1 (2.7) pg/mL, median (IQR)] and IL-6 levels in synovial fluid were associated with MMPs and radiographic disease severity. Natural stilbenoids monomethyl Pinosylvin and Pinosylvin increased aggrecan expression and suppressed IL-6 production in OA chondrocytes. The results propose that IL-6 is produced within OA joints and has an important role in the pathogenesis of OA. Stilbenoid compounds monomethyl Pinosylvin and Pinosylvin appeared to have disease-modifying potential in OA chondrocytes.
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Natural Stilbenoids Have Anti-Inflammatory Properties in Vivo and Down-Regulate the Production of Inflammatory Mediators NO, IL6, and MCP1 Possibly in a PI3K/Akt-Dependent Manner.
Journal of natural products, 2018Co-Authors: Heikki Eräsalo, Mari Hämäläinen, Tiina Leppänen, Ilari Mäki-opas, Mirka Laavola, Raisa Haavikko, Jari Yli-kauhaluoma, Eeva MoilanenAbstract:Stilbenoids are a group of polyphenolic compounds found in plants, trees, berries, and nuts. Stilbenoids have been shown to serve an antimicrobial and antifungal function in plants. There is also evidence that as a part of the human diet, stilbenoids play an important role as antioxidants and may have anti-inflammatory effects. The PI3K/Akt pathway is a well-characterized signaling pathway controlling cellular functions involved in growth and cell cycle and in metabolism. There is also increasing evidence to show the involvement of this pathway in the regulation of inflammatory responses. In the present study, an attempt was made to investigate the anti-inflammatory properties of the naturally occurring stilbenoids Pinosylvin (1), monomethylPinosylvin (2), resveratrol (3), pterostilbene (4), piceatannol (5), and rhapontigenin (6). Glycosylated derivatives of piceatannol and rhapontigenin, namely, astringin (7) and rhaponticin (8), respectively, were also investigated. In addition to the natural stilbenoid...
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Pinosylvin and monomethylPinosylvin constituents of an extract from the knot of pinus sylvestris reduce inflammatory gene expression and inflammatory responses in vivo
Journal of Agricultural and Food Chemistry, 2015Co-Authors: Mirka Laavola, Bjarne Holmbom, Tiina Leppänen, Christer Eckerman, Riina Nieminen, Eeva MoilanenAbstract:Scots pine (Pinus sylvestris) is known to be rich in phenolic compounds, which may have anti-inflammatory properties. The present study investigated the anti-inflammatory effects of a knot extract from P. sylvestris and two stilbenes, Pinosylvin and monomethylPinosylvin, isolated from the extract. Inflammation is characterized by increased release of pro-inflammatory and regulatory mediators including nitric oxide (NO) produced by the inducible nitric oxide synthase (iNOS) pathway. The knot extract (EC50 values of 3 and 3 μg/mL) as well as two of its constituents, Pinosylvin (EC50 values of 13 and 15 μM) and monomethylPinosylvin (EC50 values of 8 and 12 μM), reduced NO production and iNOS expression in activated macrophages. They also inhibited the production of inflammatory cytokines IL-6 and MCP-1. More importantly, Pinosylvin and monomethylPinosylvin exerted a clear anti-inflammatory effect (80% inhibition at the dose of 100 mg/kg) in the standard in vivo model, carrageenan-induced paw inflammation in the mouse, with the effect being comparable to that of a known iNOS inhibitor L-NIL. The results reveal that the Scots pine stilbenes Pinosylvin and monomethylPinosylvin are potential anti-inflammatory compounds.
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Pinosylvin and monomethylPinosylvin constituents of an extract from the knot of pinus sylvestris reduce inflammatory gene expression and inflammatory responses in vivo
Journal of Agricultural and Food Chemistry, 2015Co-Authors: Mirka Laavola, Bjarne Holmbom, Tiina Leppänen, Christer Eckerman, Riina Nieminen, Eeva MoilanenAbstract:Scots pine (Pinus sylvestris) is known to be rich in phenolic compounds, which may have anti-inflammatory properties. The present study investigated the anti-inflammatory effects of a knot extract from P. sylvestris and two stilbenes, Pinosylvin and monomethylPinosylvin, isolated from the extract. Inflammation is characterized by increased release of pro-inflammatory and regulatory mediators including nitric oxide (NO) produced by the inducible nitric oxide synthase (iNOS) pathway. The knot extract (EC50 values of 3 and 3 μg/mL) as well as two of its constituents, Pinosylvin (EC50 values of 13 and 15 μM) and monomethylPinosylvin (EC50 values of 8 and 12 μM), reduced NO production and iNOS expression in activated macrophages. They also inhibited the production of inflammatory cytokines IL-6 and MCP-1. More importantly, Pinosylvin and monomethylPinosylvin exerted a clear anti-inflammatory effect (80% inhibition at the dose of 100 mg/kg) in the standard in vivo model, carrageenan-induced paw inflammation in ...