Chemical induction of interleukin-8, a proinflammatory chemokine, in human epidermal keratinocyte cultures and its relation to cytogenetic toxicity

Biologically Synthesized Rosa rugosa-Based Gold Nanoparticles Suppress Skin Inflammatory Responses via MAPK and NF-κB Signaling Pathway in TNF-α/IFN-γ-Induced HaCaT Keratinocytes

Nanotechnology-applied materials and related therapeutics have gained attention for treating inflammatory skin diseases. The beach rose (Rosa rugosa), belonging to the family Rosaceae, is a perennial, deciduous woody shrub endemic to northeastern Asia. In this study, R. rugosa-based gold nanoparticles (RR-AuNPs) were biologically synthesized under optimal conditions to explore their potential as anti-inflammatory agents for treating skin inflammation. The synthesized RR-AuNPs were analyzed using field emission-transmission electron microscopy, energy-dispersive X-ray spectrometry, selected-area electron diffraction, and X-ray diffraction. The uniformly well-structured AuNPs showed near-spherical and polygonal shapes. Cell viability evaluation and optical observation results showed that the RR-AuNPs were absorbed by human keratinocytes without causing cytotoxic effects. The effects of RR-AuNPs on the skin inflammatory response were investigated in human keratinocytes treated with tumor necrosis factor-α/interferon-γ (T + I). The results showed that T + I-stimulated increases in inflammatory mediators, including chemokines, interleukins, and reactive oxygen species, were significantly suppressed by RR-AuNP treatment in a concentration-dependent manner. The western blotting results indicated that the RR-AuNP-mediated anti-inflammatory effects were highly associated with the suppression of inflammatory signaling, mitogen-activated protein kinase, and nuclear factor-κB. These results demonstrate that plant extract-based AuNPs are novel anti-inflammatory candidates for topical application to treat skin inflammation.

AGSE: A Novel Grape Seed Extract Enriched for PP2A Activating Flavonoids That Combats Oxidative Stress and Promotes Skin Health

Environmental stimuli attack the skin daily resulting in the generation of reactive oxygen species (ROS) and inflammation. One pathway that regulates oxidative stress in skin involves Protein Phosphatase 2A (PP2A), a phosphatase which has been previously linked to Alzheimer’s Disease and aging. Oxidative stress decreases PP2A methylation in normal human dermal fibroblasts (NHDFs). Thus, we hypothesize agents that increase PP2A methylation and activity will promote skin health and combat aging. To discover novel inhibitors of PP2A demethylation activity, we screened a library of 32 natural botanical extracts. We discovered Grape Seed Extract (GSE), which has previously been reported to have several benefits for skin, to be the most potent PP2A demethylating extract. Via several fractionation and extraction steps we developed a novel grape seed extract called Activated Grape Seed Extract (AGSE), which is enriched for PP2A activating flavonoids that increase potency in preventing PP2A demethylation when compared to commercial GSE. We then determined that 1% AGSE and 1% commercial GSE exhibit distinct gene expression profiles when topically applied to a 3D human skin model. To begin to characterize AGSE’s activity, we investigated its antioxidant potential and demonstrate it reduces ROS levels in NHDFs and cell-free assays equal to or better than Vitamin C and E. Moreover, AGSE shows anti-inflammatory properties, dose-dependently inhibiting UVA, UVB and chemical-induced inflammation. These results demonstrate AGSE is a novel, multi-functional extract that modulates methylation levels of PP2A and supports the hypothesis of PP2A as a master regulator for oxidative stress signaling and aging in skin.

Methyl Linderone Suppresses TPA-Stimulated IL-8 and MMP-9 Expression Via the ERK/STAT3 Pathway in MCF-7 Breast Cancer Cells

Methyl linderone (ML), a cyclo-pentenedione, was isolated from the fruit of Lindera erythrocarpa Makino (family Lauraceae). This plant has well-known anti-inflammatory effects; however, the anti-cancer effects of ML have not yet been reported. Thus, in the present study we investigated the effects of ML on the metastasis of human breast cancer cells. We used 12-O-tetradecanoyl phorbol-13-acetate (TPA)-stimulated MCF-7 cells as the cell model to study the effects of ML on invasion and migration. ML was found to reduce the invasion and migration rate of TPA-stimulated MCF-7 cells. Moreover, it inhibited two metastasis-related factors, matrix metalloproteinase-9 (MMP-9) and interleukin-8 (IL-8), at the mRNA and protein expression levels, in TPA-treated MCF-7 cells. The mechanism by which ML exerted these effects was through the inhibition of translocation of activator protein-1 (AP-1) and signal transducer and activator of transcription-3 (STAT3), mediated via phosphorylation of extracellular signal-regulated kinase (ERK). Taken together, our findings indicated that ML attenuated the TPA-stimulated invasion and migration of MCF-7 cells by suppressing the phosphorylation of ERK and its downstream factors, AP-1 and STAT3. Therefore, ML is a potential agent for the treatment of breast cancer metastasis.

Anti-acne vulgaris effect including skin barrier improvement and 5α-reductase inhibition by tellimagrandin I from Carpinus tschonoskii

BACKGROUND

Carpinus tschonoskii (CT) has been previously studied for various activities in the improvement of skin diseases. In the present study, we examined the in vitro anti-acne vulgaris (AV) effect of CT leaves (CTL) and tellimagrandin I (TI), one of the main ellagitannins from CT, including skin barrier improvement and 5α-reductase inhibitory activity.

METHODS

To test the anti-AV activities of CTL and TI, firstly, anti-oxidative and anti-inflammatory activities including DPPH radical scavenging activity, nitric oxide (NO) inhibitory activity, and cytokines [interleukin (IL)-6 and IL-8] were tested. Skin barrier improvement experiments were tested using developing cornified envelope (CE) formation, and filaggrin mRNA expression level was determined by RT-PCR. The 5α-reductase inhibitory activity was determined by measuring the testosterone levels in rat liver microsomes.

RESULTS

CTL and TI showed potent anti-oxidative activity and anti-inflammatory activities. Especially, the cytokine production inhibitory activities of TI were found to be similar to the positive control, epigallocatechin gallate (EGCG). CTL and TI enhanced the CE formation and filaggrin mRNA expression levels and showed potent activities compared to that in the positive control, 1.5 mM Ca²⁺. In additionally, CTL and TI showed 5α-reductase inhibitory activities in a dose-dependent manner.

CONCLUSION

The results showed that CTL and TI inhibit AV endogenous factors such as 5α-reductase and inflammatory cytokines and affect exogenous factors such as developing skin barrier function (CE and filaggrin levels). Therefore, CTL and TI may be plant-derived agent, promising in the treatment of acne vulgaris.

Anti-Inflammatory Effects of Phenolic Compounds Isolated from Quercus Mongolica Fisch. ex Ledeb. on UVB-Irradiated Human Skin Cells

Quercus mongolica Fisch. ex Ledeb. (QM) has been used as an oriental traditional medicine to relieve hemorrhoids, fever, and enteritis. We screened the inhibitory activities of the extracts and compounds (1–6) isolated from QM on the production of inflammatory cytokines and chemokines to evaluate their anti-inflammatory activities. Further, we evaluated the expression levels of cytokines, chemokines, and immune factors on pedunculagin (PC, 1), which was selected from isolated compounds (1–6) because of its potential anti-inflammation effect. Additionally, we evaluated whether the inflammation mitigation effects of PC (1) following UVB exposure in keratinocytes occurred because of nuclear factor (NF)-κB and signal transducer and activator of transcription (STAT)/Janus kinase (JAK) activation. PC (1) remarkably suppressed interleukin (IL)-6, IL-10, IL-13, and monocyte chemoattractant protein-1 (MCP-1) mRNA expression and reduced the mRNA expression level of Cyclooxygenase-2 (COX-2) and also reduced the phosphorylation of p38 mitogen-activated protein kinases (p38), c-Jun N-terminal kinase (JNK), and extracellular signal-regulated kinase (ERK) in a concentration-dependent manner.

Anti-Inflammatory and Skin-Moisturizing Effects of a Flavonoid Glycoside Extracted from the Aquatic Plant Nymphoides indica in Human Keratinocytes

Nymphoides indica, an aquatic plant, is used as folk medicine in some countries. Our previous study demonstrated that the methanol extract of N. indica inhibited the activity of tyrosinases, tyrosine related protein (TRP)1 and TRP2, and microphthalmia-associated transcription factor, as well as the activity of protein kinase A, by effectively inhibiting cyclic adenosine monophosphate. Although the biological activities of N. indica extract have been reported, there are no reports on the skin bioactivity of the main compound(s) on human keratinocytes. This study investigated the anti-inflammatory and moisturizing effects of quercetin 3,7-dimethyl ether 4′-glucoside (QDG) isolated from N. indica. In brief, ultraviolet B irradiated keratinocytes were pretreated with different concentrations of QDG, and the effects of QDG on various inflammatory markers were determined. QDG significantly inhibited inflammation-related cytokines and chemokines and enhanced the activation of skin barrier factors. Additionally, QDG also attenuated phosphorylation inhibition of the upstream cytokines and nuclear factor-κB expression. These results suggest that QDG isolated from N. indica may serve as a potential source of bioactive substances for chronic inflammatory skin diseases.

Growth Hormone Releasing Peptide-2 Attenuation of Protein Kinase C-Induced Inflammation in Human Ovarian Granulosa Cells

Cyclooxygenase-2 (COX-2) and interleukin-8 (IL-8) are two important inflammatory mediators in ovulation. Ghrelin may modulate inflammatory signaling via growth hormone secretagogue receptors. We investigated the role of ghrelin in KGN human ovarian granulosa cells using protein kinase C (PKC) activator phorbol 12, 13-didecanoate (PDD) and synthetic ghrelin analog growth hormone releasing peptide-2 (GHRP-2). GHRP-2 attenuated PDD-induced expression of protein and mRNA, the promoter activity of COX-2 and IL-8 genes, and the secretion of prostaglandin E2 (PGE₂) and IL-8. GHRP-2 promoted the degradation of PDD-induced COX-2 and IL-8 proteins with the involvement of proteasomal and lysosomal pathways. PDD-mediated COX-2 production acts via the p38, c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathways; PDD-mediated IL-8 production acts via the p38, JNK and ERK pathways. GHRP-2 reduced the PDD-induced phosphorylation of p38 and JNK and activator protein 1 (AP-1) reporter activation and PDD-induced NF-κB nuclear translocation and reporter activation. The inhibitors of mitogen-activated protein kinase phosphatase-1 (MKP-1) and protein phosphatase 2 (PP2A) reduced the inhibitory effect of GHRP-2 on PDD-induced COX-2 and IL-8 expression. Our findings demonstrate an anti-inflammatory role for ghrelin (GHRP-2) in PKC-mediated inflammation of granulosa cells, at least in part, due to its inhibitory effect on PKC-induced activation of p38, JNK and NF-κB, possibly by targeting to MKP-1 and PP2A.

Latent effects of fibronectin, alpha5beta1 integrin, alphaVbeta5 integrin and the cytoskeleton regulate pancreatic carcinoma cell IL-8 secretion

Interactions between tumour cells and the microenvironment are increasingly recognised to have an influence on cancer progression. In pancreatic carcinoma, a highly desmoplastic stroma with abnormal extracellular matrix (ECM) protein and interleukin-8 (IL-8) expression is seen. To investigate whether the ECM may further contribute to abnormalities in the microenvironment by influencing IL-8 secretion, we cultured the Mia PaCa2 pancreatic carcinoma cell line on fibronectin. This resulted in a dose-dependent increase in IL-8 secretion, which was RGD dependent and accompanied by cell spreading and proliferation. The role of spreading was assessed by disruption of the cytoskeleton with cytochalasin D, resulting in a large increase in IL-8 secretion, which was reduced from 31- to 24-fold by fibronectin. This remarkable response was associated with inhibition of spreading and proliferation and represents a novel cytoskeletal function. To investigate whether it could be accounted for by the loss of integrin-mediated signalling, the expressed α5β1, αVβ5 and α3β1 integrins were inhibited. α5β1 inhibition prevented spreading and proliferation but produced a much smaller rise in IL-8 secretion than cytochalasin D. αVβ5 inhibition alone had only minor effects but when inhibited in combination with α5β1 completely abolished the response to fibronectin. These results reveal latent stimulatory effects of the αVβ5 integrin on IL-8 secretion and suggest that integrin crosstalk may limit the induction of IL-8 secretion by fibronectin. However, the magnitude of IL-8 secretion induced by cytochalasin cannot be accounted for by integrin signalling and may reflect the influence of another signalling pathway or a novel, intrinsic cytoskeletal function.