Oligomeric α-Synuclein induces skin degeneration in a reconstructed human epidermis model

Cell senescence may promote epidermal inflammation and degeneration, termed as inflammaging, which is accompanied by keratinocyte loss, resulting in fine lines of wrinkles. Recent findings showed that healthy elderly skin expresses age- and neuron-related amyloidogenic proteins, such as tau, β-Amyloid34, and α-synuclein (α-Syn), typically found in patients with neurodegenerative diseases. These proteins form toxic aggregates that trigger inflammatory signals. Herein, we investigated the impact of oligomeric α-Syn (Oα-Syn) on the neurosphere (NP) and the reconstructed human epidermis (RHE) 3D models. First, we found the expression of α-Syn, β-Amyloid, and amyloid precursor protein (APP) in the RHE. Second, we challenged the RHE and NP with Oα-Syn, which decreased RHE regeneration, measured by the percentage of cell proliferation and thickness of the stratum basale, but did not affect NP neurite outgrowth. Oα-Syn did not decrease the number of human neonatal epidermal keratinocytes (HEKn) but, as seen for the RHE, it also decreased the proliferation of HEKn. We confirmed that the oligomeric, and not the monomeric α-Syn species, accounted for the proliferation-decreasing effect. Oα-Syn also increased the NF-κB nuclear translocation in HEKn analyzed by nucleus/cytoplasm NF-κB fluorescence intensity. In addition, Oα-Syn triggered inflammation in the RHE, by increasing the mRNA levels of IL-1β and tumor necrosis factor-alpha (TNF-α), and the release of TNF-α in a time-dependent manner. These findings show that Oα-Syn does not affect neurite outgrowth but induces a decrease in keratinocyte proliferation along with epidermal inflammation. With our tridimensional models, we demonstrated that the neurodegenerative protein Oα-Syn also degenerates the epidermis, drawing attention to the need of target-based screening to prevent and treat the effects of skin aging.

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Plasmin-induced expression of cytokines and tissue factor in human monocytes involves AP-1 and IKKβ-mediated NF-κB activation

Blood ◽

10.1182/blood.v97.12.3941 ◽

2001 ◽

Vol 97 (12) ◽

pp. 3941-3950 ◽

Cited By ~ 102

Author(s):

Tatiana Syrovets ◽

Marina Jendrach ◽

Angela Rohwedder ◽

Almut Schüle ◽

Thomas Simmet

Keyword(s):

Tissue Factor ◽

Nuclear Translocation ◽

Lipid Mediator ◽

Mrna Levels ◽

Dependent Manner ◽

Human Monocytes ◽

Mobility Shift ◽

Concentration Dependent Manner ◽

Iκb Kinase ◽

Tnf Α

It was previously shown that plasmin activates human peripheral monocytes in terms of lipid mediator release and chemotactic migration. Here it is demonstrated that plasmin induces proinflammatory cytokine release and tissue factor (TF) expression by monocytes. Plasmin 0.043 to 1.43 CTA U/mL, but not active site-blocked plasmin, triggered concentration-dependent expression of mRNA for interleukin-1α (IL-1α), IL-1β, tumor necrosis factor-α (TNF-α), and TF with maximum responses after 4 hours. Plasmin-mediated mRNA expression was inhibited in a concentration-dependent manner by the lysine analoguetrans-4-(aminomethyl)cyclohexane-1-carboxylic acid (t-AMCA). Increases in mRNA levels were followed by concentration- and time-dependent release of IL-1α, IL-1β and TNF-α and by TF expression on monocyte surfaces. Neither cytokines nor TF could be detected when monocytes were preincubated with actinomycin D or cycloheximide. Electrophoretic mobility shift assays indicated plasmin-induced activation of NF-κB; DNA-binding complexes were composed of p50, p65, and c-Rel, as shown by supershift experiments. Nuclear translocation of NF-κB/Rel proteins coincided with IκBα degradation. At variance with endotoxic lipopolysaccharide, plasmin elicited the rapid degradation of another cytoplasmic NF-κB inhibitor, p105. Proteolysis of NF-κB inhibitors was apparently due to transient activation of IκB kinase (IKK) β that reached maximum activity at 1 hour after plasmin stimulation. In addition, AP-1 binding was increased in plasmin-treated monocytes, with most complexes composed of JunD, c-Fos, and FosB. These findings further substantiate the role of plasmin as a proinflammatory activator of human monocytes and reveal an important new link between the plasminogen-plasmin system and inflammation.

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Transglutaminase 2 Up-Regulation Is Associated with Inflammatory Response in PBMC from Healthy Subjects with Hypovitaminosis D

Medical Sciences ◽

10.3390/medsci6040103 ◽

2018 ◽

Vol 6 (4) ◽

pp. 103 ◽

Cited By ~ 2

Author(s):

Daniela Caccamo ◽

Nadia Ferlazzo ◽

Monica Currò ◽

Sergio Ricca ◽

Riccardo Ientile

Keyword(s):

Vitamin D ◽

Immune Response ◽

Molecular Mechanisms ◽

Nuclear Translocation ◽

Transglutaminase 2 ◽

Hypovitaminosis D ◽

Mrna Levels ◽

Vitamin D Status ◽

Vitamin D Levels ◽

Tnf Α

Recent evidence indicated that transglutaminase 2 (TG2) is involved in the adaptive immune response. Peripheral blood mononuclear cells (PBMC) have largely been used to characterize molecular mechanisms occurring in the activation of immune response. Given that the maintenance of immune system functions requires an optimal vitamin D status, we aimed to assess the involvement of TG2/NF-κB signaling in cytokine production in PBMC isolated from adult subjects with different vitamin D status. We observed TG2 up-regulation and a significant positive correlation between TG2 expression and tumor necrosis factor (TNF)-α mRNA levels in PBMC of recruited patients. The mRNA levels of TG2 and TNF-α were higher in PBMC of subjects having hypovitaminosis D, namely plasma 25(OH)vitamin D3 levels lower than 50 nmol/L, than in those with normal vitamin D levels. Moreover, NF-κB up-regulation and nuclear translocation were detected, concomitantly with TG2 as well as TNF-α increased expression, in PBMC of vitamin D-deficient subjects. The present findings confirm that an increase in TG2 expression exacerbates the activation of NF-κB and the production of pro-inflammatory cytokines, and suggest a link between vitamin D deficiency, TG2 up-regulation, and inflammation.

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Differential Activation of Innate Immune Responses by Adenovirus and Adeno-Associated Virus Vectors

Journal of Virology ◽

10.1128/jvi.76.9.4580-4590.2002 ◽

2002 ◽

Vol 76 (9) ◽

pp. 4580-4590 ◽

Cited By ~ 235

Author(s):

Anne-Kathrin Zaiss ◽

Qiang Liu ◽

Gloria P. Bowen ◽

Norman C. W. Wong ◽

Jeffrey S. Bartlett ◽

...

Keyword(s):

Immune System ◽

Intravenous Administration ◽

Innate Immune System ◽

Innate Immune ◽

Target Cells ◽

Mrna Levels ◽

Dependent Manner ◽

Adeno Associated Virus ◽

Tnf Α ◽

Adenovirus Vectors

ABSTRACT Adenovirus vectors induce acute inflammation of infected tissues due to activation of the innate immune system and expression of numerous chemokines and cytokines in transduced target cells. In contrast, adeno-associated virus (AAV) vectors are not associated with significant inflammation experimentally or clinically. We tested the ability of AAV vectors to induce the expression of chemokines in vitro and to activate the innate immune system in vivo. In human HeLa cells and murine renal epithelium-derived cells (REC cells) the adenovirus vector AdlacZ induced the expression of multiple inflammatory chemokines including RANTES, interferon-inducible protein 10 (IP-10), interleukin-8 (IL-8), MIP-1β, and MIP-2 in a dose-dependent manner. The use of AAVlacZ did not induce the expression of these chemokines above baseline levels despite 40-fold-greater titers than AdlacZ and greater amounts of intracellular AAVlacZ genomes according to Southern and slot blot analysis. This finding confirmed that the lack of AAVlacZ induction of chemokine was not due to reduced transduction. In DBA/2 mice, the intravenous administration of 2.5 × 1011 particles of AAVlacZ resulted in the rapid induction of liver tumor necrosis factor alpha (TNF-α), RANTES, IP-10, MIP-1β, MCP-1, and MIP-2 mRNAs. However, 6 h following injection, chemokine mRNA levels returned to baseline. As expected, administration of 10-fold less AdlacZ caused an induction of liver TNF-α and chemokine mRNAs that persisted for more than 24 h posttransduction. Whereas intravenous administration of 2.5 × 1011 particles of AAVlacZ triggered a transient infiltration of neutrophils and CD11b+ cells into liver, this response stood in contrast to widespread inflammation and toxicity induced by AdlacZ. Kupffer cell depletion abolished AAVlacZ but not AdlacZ-induced chemokine expression and neutrophil infiltration. In summary, these results show that AAV vectors activate the innate immune system to a lesser extent than do adenovirus vectors and offer a possible explanation for the reduced inflammatory properties of AAV compared to adenovirus vectors.

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TLR5-mediated activation of p38 MAPK regulates epithelial IL-8 expression via posttranscriptional mechanism

AJP Gastrointestinal and Liver Physiology ◽

10.1152/ajpgi.00503.2002 ◽

2003 ◽

Vol 285 (2) ◽

pp. G282-G290 ◽

Cited By ~ 85

Author(s):

Yimin Yu ◽

Hui Zeng ◽

Sean Lyons ◽

Adam Carlson ◽

Didier Merlin ◽

...

Keyword(s):

P38 Mapk ◽

Mrna Stability ◽

Mrna Translation ◽

Mrna Levels ◽

Dependent Manner ◽

Maximal Inhibition ◽

Mapk Activation ◽

Intestinal Epithelia ◽

Tnf Α ◽

Sb 203580

Toll-like receptors (TLRs) activate antimicrobial gene expression in response to detection of specific bacterial products. Relatively little is known about TLR5, the only TLR thought to be preferentially expressed by epithelial cells, beyond that it confers activation of the transcription factor NF-κB in a MyD-88 dependent manner in response to flagellin. Because TLRs, in general, are also thought to signal through members of the MAPK family, we examined flagellin-induced MAPK activation (via examining its phosphorylation status) and its subsequent role in expression of the chemokine IL-8 in polarized intestinal epithelia. Flagellin, like other proinflammatory stimuli (TNF-α, Salmonella typhimurium), activated p38 MAPK in a TLR5-dependent manner, whereas aflagellate bacteria or EGF did not activate this kinase. Although ERK1 and -2 were also observed to be activated in response to flagellin, their activation was not restricted to proinflammatory stimuli because they were also potently activated by aflagellate bacteria ( S. typhimurium or Escherichia coli) and EGF (neither of which activate NF-κB in these cells). Pharmacological inhibition of p38 MAPK (by SB-203580) potently (IC50 = 10 nM) reduced expression of IL-8 protein (maximal inhibition, 75%) but had no effect on NF-κB activation, only slightly attenuated upregulation of IL-8 mRNA levels in response to flagellin, and did not effect IL-8 mRNA stability. Together, these results indicate that epithelial TLR5 mediates p38 activation and subsequently regulates flagellin-induced IL-8 expression independently of NF-κB, probably by influencing IL-8 mRNA translation.

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Daphnetin inhibits proliferation and inflammatory response in human HaCaT keratinocytes and ameliorates imiquimod-induced psoriasis-like skin lesion in mice

Biological Research ◽

10.1186/s40659-020-00316-0 ◽

2020 ◽

Vol 53 (1) ◽

Author(s):

Jintao Gao ◽

Fangru Chen ◽

Huanan Fang ◽

Jing Mi ◽

Qi Qi ◽

...

Keyword(s):

Skin Lesion ◽

Inflammatory Response ◽

Mouse Model ◽

Nuclear Translocation ◽

Marker Gene ◽

Inflammatory Factors ◽

Mrna Levels ◽

Hacat Keratinocytes ◽

Tnf Α

Abstract Background Psoriasis is a common chronic inflammatory skin disease. Keratinocytes hyperproliferation and excessive inflammatory response contribute to psoriasis pathogenesis. The agents able to attenuate keratinocytes hyperproliferation and excessive inflammatory response are considered to be potentially useful for psoriasis treatment. Daphnetin exhibits broad bioactivities including anti-proliferation and anti-inflammatory. This study aims to evaluate the anti-psoriatic potential of daphnetin in vitro and in vivo, and explore underlying mechanisms. Methods HaCaT keratinocytes was stimulated with the mixture of IL-17A, IL-22, oncostatin M, IL-1α, and TNF-α (M5) to establish psoriatic keratinocyte model in vitro. Cell viability was measured using Cell Counting Kit-8 (CCK-8). Quantitative Real-Time PCR (qRT-PCR) was performed to measure the mRNA levels of hyperproliferative marker gene keratin 6 (KRT6), differentiation marker gene keratin 1 (KRT1) and inflammatory factors IL-1β, IL-6, IL-8, TNF-α, IL-23A and MCP-1. Western blotting was used to detect the protein levels of p65 and p-p65. Indirect immunofluorescence assay (IFA) was carried out to detect p65 nuclear translocation. Imiquimod (IMQ) was used to construct psoriasis-like mouse model. Psoriasis severity (erythema, scaling) was scored based on Psoriasis Area Severity Index (PASI). Hematoxylin and eosin (H&E) staining was performed to examine histological change in skin lesion. The expression of inflammatory factors including IL-6, TNF-α, IL-23A and IL-17A in skin lesion was measured by qRT-PCR. Results Daphnetin attenuated M5-induced hyperproliferation in HaCaT keratinocytes. M5 stimulation significantly upregulated mRNA levels of IL-1β, IL-6, IL-8, TNF-α, IL-23A and MCP-1. However, daphnetin treatment partially attenuated the upregulation of those inflammatory cytokines. Daphnetin was found to be able to inhibit p65 phosphorylation and nuclear translocation in HaCaT keratinocytes. In addition, daphnetin significantly ameliorate the severity of skin lesion (erythema, scaling and epidermal thickness, inflammatory cell infiltration) in IMQ-induced psoriasis-like mouse model. Daphnetin treatment attenuated IMQ-induced upregulation of inflammatory cytokines including IL-6, IL-23A and IL-17A in skin lesion of mice. Conclusions Daphnetin was able to attenuate proliferation and inflammatory response induced by M5 in HaCaT keratinocytes through suppression of NF-κB signaling pathway. Daphnetin could ameliorate the severity of skin lesion and improve inflammation status in IMQ-induced psoriasis-like mouse model. Daphnetin could be an attractive candidate for future development as an anti-psoriatic agent.

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Protective effect of Cordyceps sinensis extract on lipopolysaccharide-induced acute lung injury in mice

Bioscience Reports ◽

10.1042/bsr20190789 ◽

2019 ◽

Vol 39 (6) ◽

Cited By ~ 6

Author(s):

Shuiqiao Fu ◽

Weina Lu ◽

Wenqiao Yu ◽

Jun Hu

Keyword(s):

Acute Lung Injury ◽

Lung Injury ◽

Protective Effect ◽

Weight Ratio ◽

Cordyceps Sinensis ◽

Myeloperoxidase Activity ◽

Mrna Levels ◽

Dependent Manner ◽

Tnf Α ◽

Cox 2

Abstract Background: To study the protective effect of Cordyceps sinensis extract (Dong Chong Xia Cao in Chinese [DCXC]) on experimental acute lung injury (ALI) mice. Methods and results: ALI model was induced by intratracheal-instilled lipopolysaccharide (LPS, 2.4 mg/kg) in BALB/c male mice. The mice were administrated DCXC (ig, 10, 30, 60 mg/kg) in 4 and 8 h after receiving LPS. Histopathological section, wet/dry lung weight ratio and myeloperoxidase activity were detected. Bronchoalveolar lavage fluid (BALF) was collected for cell count, the levels of tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6) and nitric oxide (NO) in BALF was detected by ELISA, the protein and mRNA expression of nuclear factor-κB p65 (NF-κB p65), inducible NO synthase (iNOS) and cyclooxygenase-2 (COX-2) in lung tissue was detected by Western blot and RT-PCR. The result showed that DCXC could reduce the degree of histopathological injury, wet/dry weight ratio (W/D ratio) and myeloperoxidase activity (P<0.05) with a dose-dependent manner. The increased number of total cells, neutrophils and macrophages in BALF were significantly inhibited by DCXC treatment (P<0.05). The increased levels of TNF-α, IL-1β, IL-6 and NO in BALF after LPS administration was significantly reduced by DCXC (P<0.05). In addition, the increased protein and mRNA levels of iNOS, COX-2 and NF-κB p65 DNA binding ability in LPS group were dose-dependently reduced by DCXC treatment (P<0.05). Conclusion: DCXC could play an anti-inflammatory and antioxidant effect on LPS-induced ALI through inhibiting NF-κB p65 phosphorylation, and the expression of COX-2 and iNOS in lung. The result showed that DCXC has a potential protective effect on the ALI.

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Nerolidol Mitigates Colonic Inflammation: An Experimental Study Using both In Vivo and In Vitro Models

Nutrients ◽

10.3390/nu12072032 ◽

2020 ◽

Vol 12 (7) ◽

pp. 2032

Author(s):

Vishnu Raj ◽

Balaji Venkataraman ◽

Saeeda Almarzooqi ◽

Sanjana Chandran ◽

Shreesh K. Ojha ◽

...

Keyword(s):

Nuclear Translocation ◽

In Vitro Models ◽

Mrna Levels ◽

Colonic Inflammation ◽

Tnf Α ◽

Cox 2 ◽

Anti Inflammatory ◽

Ht 29

Nerolidol (NED) is a naturally occurring sesquiterpene alcohol present in various plants with potent anti-inflammatory effects. In the current study, we investigated NED as a putative anti-inflammatory compound in an experimental model of colonic inflammation. C57BL/6J male black mice (C57BL/6J) were administered 3% dextran sodium sulfate (DSS) in drinking water for 7 days to induce colitis. Six groups received either vehicle alone or DSS alone or DSS with oral NED (50, 100, and 150 mg/kg body weight/day by oral gavage) or DSS with sulfasalazine. Disease activity index (DAI), colonic histology, and biochemical parameters were measured. TNF-α-treated HT-29 cells were used as in vitro model of colonic inflammation to study NED (25 µM and 50 µM). NED significantly decreased the DAI and reduced the inflammation-associated changes in colon length as well as macroscopic and microscopic architecture of the colon. Changes in tissue Myeloperoxidase (MPO) concentrations, neutrophil and macrophage mRNA expression (CXCL2 and CCL2), and proinflammatory cytokine content (IL-1β, IL-6, and TNF-α) both at the protein and mRNA level were significantly reduced by NED. The increase in content of the proinflammatory enzymes, COX-2 and iNOS induced by DSS were also significantly inhibited by NED along with tissue nitrate levels. NED promoted Nrf2 nuclear translocation dose dependently. NED significantly increased antioxidant enzymes activity (Superoxide dismutase (SOD) and Catalase (CAT)), Hemeoxygenase-1 (HO-1), and SOD3 mRNA levels. NED treatment in TNF-α-challenged HT-29 cells significantly decreased proinflammatory chemokines (CXCL1, IL-8, CCL2) and COX-2 mRNA levels. NED supplementation attenuates colon inflammation through its potent antioxidant and anti-inflammatory activity both in in vivo and in vitro models of colonic inflammation.

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Evidence that estrogen receptor β enhances MMP-13 promoter activity in HIG-82 cells and that this enhancement can be influenced by ligands and involves specific promoter sites

Biochemistry and Cell Biology ◽

10.1139/o07-016 ◽

2007 ◽

Vol 85 (3) ◽

pp. 326-336 ◽

Cited By ~ 11

Author(s):

Ting Lu ◽

Yamini Achari ◽

Jerome B. Rattner ◽

David A. Hart

Keyword(s):

Estrogen Receptor ◽

Promoter Activity ◽

Estrogen Receptor Β ◽

Mrna Levels ◽

Dependent Manner ◽

Connective Tissues ◽

Matrix Metalloproteinase 13 ◽

Promoter Construct ◽

The Impact ◽

Dose Dependent

Degradation of articular cartilage is characteristic of osteoarthritis, and matrix metalloproteinase-13 (MMP-13) has been implicated in this condition. Estrogen receptors (ERs) are present in connective tissues, indicating these tissues' potential responsiveness to estrogen. We based this study on the hypothesis that estrogen receptor β (ERβ) can modulate MMP-13 promoter activity. Transfection of cells with ERβ constructs led to the induction of the endogenous MMP-13 gene, as evidenced by increased mRNA levels. The results also indicated that MMP-13 promoter construct activity in the HIG-82 cell line significantly increased when ERβ was present, and that estrogen downregulated this response in a dose-dependent manner. ERβ was shown to enhance MMP-13 expression somewhat more strongly than ERα, and the impact of a number of selective ER modulators (tamoxifen, raloxifene, and ICI 182,780) on ERβ enhancement of promoter activity was found to be significantly less than that of estrogen. Furthermore, transcription regulatory sites in the MMP-13 promoter, specifically AP-1 and PEA-3, were shown to act in conjunction to mediate ERβ effects. Thus, ERβ likely influences MMP-13 promoter expression in normal and disease processes.

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TNF-α-Induced NF-κB Activation Stimulates Skeletal Muscle Glycolytic Metabolism Through Activation of HIF-1α

Endocrinology ◽

10.1210/en.2014-1591 ◽

2015 ◽

Vol 156 (5) ◽

pp. 1770-1781 ◽

Cited By ~ 30

Author(s):

A. H. V. Remels ◽

H. R. Gosker ◽

K. J. P. Verhees ◽

R. C. J. Langen ◽

A. M. W. J. Schols

Keyword(s):

Oxidative Metabolism ◽

Lactate Production ◽

Quadriceps Muscle ◽

Metabolic Adaptation ◽

Mrna Levels ◽

Dependent Manner ◽

Glycolytic Metabolism ◽

Consistent Finding ◽

Tnf Α ◽

Muscle Biopsies

A shift in quadriceps muscle metabolic profile toward decreased oxidative metabolism and increased glycolysis is a consistent finding in chronic obstructive pulmonary disease (COPD). Chronic inflammation has been proposed as a trigger of this pathological metabolic adaptation. Indeed, the proinflammatory cytokine TNF-α impairs muscle oxidative metabolism through activation of the nuclear factor-κB (NF-κB) pathway. Putative effects on muscle glycolysis, however, are unclear. We hypothesized that TNF-α-induced NF-κB signaling stimulates muscle glycolytic metabolism through activation of the glycolytic regulator hypoxia-inducible factor-1α (HIF-1α). Wild-type C2C12 and C2C12-IκBα-SR (blocked NF-κB signaling) myotubes were stimulated with TNF-α, and its effects on glycolytic metabolism and involvement of the HIF pathway herein were investigated. As proof of principle, expression of HIF signaling constituents was investigated in quadriceps muscle biopsies of a previously well-characterized cohort of clinically stable patients with severe COPD and healthy matched controls. TNF-α increased myotube glucose uptake and lactate production and enhanced the activity and expression levels of multiple effectors of muscle glycolytic metabolism in a NF-κB-dependent manner. In addition, TNF-α activated HIF signaling, which required classical NF-κB activation. Moreover, the knockdown of HIF-1α largely attenuated TNF-α-induced increases in glycolytic metabolism. Accordingly, the mRNA levels of HIF-1α and the HIF-1α target gene, vascular endothelial growth factor (VEGF), were increased in muscle biopsies of COPD patients compared with controls, which was most pronounced in the patients with high levels of muscle TNF-α. In conclusion, these data show that TNF-α-induced classical NF-κB activation enhances muscle glycolytic metabolism in a HIF-1α-dependent manner.

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Aqueous extracts ofCimicifuga racemosaand phenolcarboxylic constituents inhibit production of proinflammatory cytokines in LPS-stimulated human whole blood

Canadian Journal of Physiology and Pharmacology ◽

10.1139/y09-091 ◽

2009 ◽

Vol 87 (11) ◽

pp. 963-972 ◽

Cited By ~ 30

Author(s):

Diethart Schmid ◽

Florian Woehs ◽

Martin Svoboda ◽

Theresia Thalhammer ◽

Peter Chiba ◽

...

Keyword(s):

Proinflammatory Cytokines ◽

Whole Blood ◽

Black Cohosh ◽

Active Principle ◽

Mrna Levels ◽

Dependent Manner ◽

Antiinflammatory Action ◽

Tnf Α ◽

Isoferulic Acid ◽

Ifn Γ

Cimicifuga racemosa (black cohosh) is commonly used in traditional medicines as treatment for menopausal symptoms and as an antiinflammatory remedy. To clarify the mechanism of action and active principle for the antiinflammatory action, the effects of aqueous C. racemosa root extracts (CRE) and its major constituents on the release of the proinflammatory cytokines IL-6, TNF-α, IFN-γ, and the chemokine IL-8 were investigated in lipopolysaccharide (LPS)-stimulated whole blood of healthy volunteers. CRE (3 µg/µL and 6 µg/µL) reduced LPS-induced release of IL-6 and TNF-α in a concentration- and time-dependent manner and almost completely blocked release of IFN-γ into the plasma supernatant. Except for IFN-γ, these effects were attenuated at longer incubation periods. IL-8 secretion was stimulated by CRE. As shown by quantitative real-time RT-PCR, effects on cytokines were based on preceding changes in mRNA levels except for IL-8. According to their content in CRE, the phenolcarboxylic compounds caffeic acid, ferulic acid, and isoferulic acid, as well as the triterpene glycosides 23-epi-26-deoxyactein and cimigenol-3-O-xyloside, were tested at representative concentrations. Among these, isoferulic acid was the prominent active principle in CRE, responsible for the observed inhibition of IL-6, TNF-α, and IFN-γ, but not for IL-8 stimulation. The effect of this compound may explain the antiinflammatory activities of CRE and its beneficial actions in rheumatism and other inflammatory diseases.

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