Evaluation of efficacy of Silybum marianum flower extract on the mitigating hair loss in vitro and in vivo.

BACKGROUND: Natural components that can exert a wide range of anti-hair loss activity with fewer side effects are in high demand. The objective of this study was to investigate the anti-hair loss potential of Silybum marianum flower extract (SMFE) in vitro and in vivo. METHODS: The effect of SMFE on dermal papilla cells was evaluated by measuring cell proliferation and VEGF production in hair follicle dermal papilla cells (HFDPCs). In addition, to confirm the effect of SMFE on dermal papilla senescence, SA-ß-gal staining and senescence associated secretory phenotype (SASP) production such as IL-6 was observed in both replicative and hydrogen peroxide (H2 O2 )-induced senescence models. In a clinical study, hair growth was determined by reconstitution analysis after shaving the hair of the clinical subject's scalp and hair area. RESULTS: SMFE increased the proliferation and VEGF production of HFDPCs. It also suppressed cellular senescence of HFDPCs and IL-6 production in replicative senescence and oxidative stress-induced senescence models. The hair density and total hair count at 16 and 24 weeks after using hair shampoo containing SMFE were significantly increased compared with those of the placebo group. CONCLUSION: SMFE has the potential to be used as a natural ingredient for alleviating hair loss.

Assessment of the anti-hair loss potential of Camellia japonica fruit shell extract in vitro.

OBJECTIVE: Hair loss is caused by various factors. Impacts of these factors are often overlapped and intensified. Currently, mitigation of hair loss is being studied by proliferating dermal papilla cells (DPCs) and inhibiting deleterious factors such as dihydrotestosterone (DHT) and oxidative stress on hair growth. Camellia japonica (C. japonica) fruit shell is a discarded part. Its biological activity remains to be elucidated. In this study, we investigated the capacity of C. japonica fruit shell extract (CJFSE) for hair loss mitigation. METHODS: MTT assay, spheroid culture and quantitative RT-PCR were performed to observe the proliferative effect of CJFSE on hair follicle dermal papilla cells (HFDPCs). Effects of CJFSE on DHT-induced hair loss were confirmed by Dkk-1 ELISA, ß-galactosidase (ß-gal) and 5α-reductase activity assay. In addition, effects of CJFSE on oxidative stress were confirmed through DPPH and ROS production assays. RESULTS: CJFSE increased the proliferation and spheroid size of HFDPCs. Expression levels of VEGF-A, Wnt-1, c-Myc and Cyclin D1 were upregulated by CJFSE. CJFSE also suppressed 5α-reductase activity and DHT-induced decrease in cell proliferation, Dkk-1 secretion and ß-gal activity. Moreover, CJFSE showed DPPH scavenging activity and ameliorated hydrogen peroxide-induced ROS production and ß-gal activity. Finally, gallic acid and protocatechuic acid were observed in CJFSE through HPLC analysis. CONCLUSION: CJFSE has the potential to alleviate hair loss by promoting hair cell growth and suppressing effects of DHT and oxidative stress on hair.

OBJECTIF: Divers facteurs sont responsables de la perte de cheveux. Souvent, les conséquences de ces facteurs se superposent et s'intensifient. Actuellement, on étudie comment atténuer la perte de cheveux en faisant proliférer les cellules de la papille dermique (DPC) et en inhibant les facteurs délétères tels que la dihydrotestostérone (DHT) et le stress oxydatif sur la croissance des cheveux. La coque du fruit du Camélia du Japon (Camelia japonica) est habituellement rejetée. Son utilité biologique reste à élucider. Dans cette étude, nous avons étudié la capacité de l'extrait de la coque du fruit du Camélia du Japon (CJFSE) dans la mitigation de la perte de cheveux. MÉTHODES: Un test MTT, une culture de sphéroïdes et une RT-PCR Quantitative ont été effectués pour observer la prolifération de CJFSE sur les cellules de la papille dermique du follicule pileux (HFDPC). Les effets du CJFSE sur la perte de cheveux induite par la DHT ont été confirmés par Dkk-1 ELISA, ß-galactosidase (ß-gal) et 5α-réductase. De plus, les effets du CJFSE sur le stress oxydatif ont été confirmés par des tests de production de DPPH et de ROS. RÉSULTATS: Le CJFSE a augmenté la prolifération et la taille sphéroïde des HFDPC. Les niveaux d'expression de VEGF-A, Wnt-1, c-Myc et cycline D1 ont été régulés de manière efficace par le CJFSE. Le CJFSE a également supprimé l'activité de la 5α-réductase et a induit la réduction de la DHT et de la prolifération cellulaire, ainsi que de la sécrétion de Dkk-1 et de l'activité ß-gal. Le CJFSE a en outre montré une activité de capture du DPPH et amélioré la production de ROS induite par le peroxyde d'hydrogène et l'activité ß-gal. Pour finir, les acides gallique et protocatéchuique ont été observés dans le CJFSE après analyse des HPLC. CONCLUSION: Le CJFSE a le potentiel d'atténuer la perte de cheveux en favorisant la croissance des cellules ciliées et en supprimant les effets de la DHT et du stress oxydatif sur les cheveux.

Immune-enhancing effect of water-soluble beta-glucan derived from enzymatic hydrolysis of yeast glucan.

Immunostimulants play an important role in the treatment of immunodeficiency. Macrophages are the first line in our immune defense system and play a critical role in the immune response. Therefore, finding new and better substances to induce an immune response by activating macrophages is an attractive research topic, especially in the fields of immunopharmacology and cancer prevention. Keratinocytes actively crosstalk with immune cells during wound repair, so enhancing the function of keratinocytes is also an important part of improving immunity. Beta-glucans are naturally occurring polysaccharides, consisting of d-glucose monomers linked by beta-glycosidic bonds. Several studies have investigated the immunomodulatory effects of beta-glucan, such as its anti-inflammatory and antibacterial properties. However, the use of yeast cell wall glucan has been limited because it is not soluble in water. In this study, we produced low-molecular-weight water-soluble yeast glucan (WSY glucan) and confirmed various aspects of its immune-enhancing effect. The structure of the beta-(1→3) and (1→6) bonds of WSY glucan were confirmed by nuclear magnetic resonance spectroscopy (1H-NMR) analysis. Our results showed that treatment with WSY glucan significantly and dose-dependently induced the production of inflammatory mediators (prostaglandin E2 (PGE2) and nitric oxide (NO)) and pro-inflammatory cytokines (tumor necrosis factor (TNF)-α and interleukin (IL)-6) in macrophages. In addition, WSY glucan treatment showed changes in the morphological structure of the macrophages and promoted phagocytic activity of the macrophages and wound healing in keratinocytes. Based on these results, WSY glucan is considered as a potential candidate for the treatment of diseases related to the weakening of the immune system without the limitation of insolubility.

Chlorogenic Acid Isomers Isolated from Artemisia lavandulaefolia Exhibit Anti-Rosacea Effects In Vitro.

Rosacea is a chronic inflammatory disease affecting facial skin. It is associated with immune and vascular dysfunction mediated via increased expression and activity of cathelicidin and kallikrein 5 (KLK5), a serine protease of stratum corneum. Therefore, KLK5 inhibitors are considered as therapeutic agents for improving the underlying pathophysiology and clinical manifestation of rosacea. Here, we isolated the active constituents of Artemisia lavandulaefolia (A. lavandulaefolia) and investigated their inhibitory effect on KLK5 protease activity. Using bioassay-guided isolation, two bioactive compounds including chlorogenic acid isomers, 3,5-dicaffeoylquinic acid (isochlorogenic acid A) (1), and 4,5-dicaffeoylquinic acid (isochlorogenic acid C) (2) were isolated from A. lavandulaefolia. In this study, we evaluated the effects of isochlorogenic acids A and C on dysregulation of vascular and immune responses to rosacea, and elucidated their molecular mechanisms of action. The two chlorogenic acid isomers inhibit KLK5 protease activity, leading to reduced conversion of inactive cathelicidin into active LL-37. This inhibition of LL-37 production by isochlorogenic acids A and C reveals the efficacy of suppressing the expression of inflammatory mediators induced by LL-37 in immune cells such as macrophages and mast cells. In addition, both isomers of chlorogenic acid directly inhibited the proliferation and migration of vascular endothelial cells induced by LL-37.

Anti-Inflammatory Activity and Mechanism of Isookanin, Isolated by Bioassay-Guided Fractionation from Bidens pilosa L.

Bidens pilosa L. (Asteraceae) has been used historically in traditional Asian medicine and is known to have a variety of biological effects. However, the specific active compounds responsible for the individual pharmacological effects of Bidens pilosa L. (B. pilosa) extract have not yet been made clear. This study aimed to investigate the anti-inflammatory phytochemicals obtained from B. pilosa. We isolated a flavonoids-type phytochemical, isookanin, from B. pilosa through bioassay-guided fractionation based on its capacity to inhibit inflammation. Some of isookanin's biological properties have been reported; however, the anti-inflammatory mechanism of isookanin has not yet been studied. In the present study, we evaluated the anti-inflammatory activities of isookanin using lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. We have shown that isookanin reduces the production of proinflammatory mediators (nitric oxide, prostaglandin E2) by inhibiting the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in LPS-stimulated macrophages. Isookanin also inhibited the expression of activator protein 1 (AP-1) and downregulated the LPS-induced phosphorylation of p38 mitogen-activated protein kinase (MAPK) and c-jun NH2-terminal kinase (JNK) in the MAPK signaling pathway. Additionally, isookanin inhibited proinflammatory cytokines (tumor necrosis factor-a (TNF-α), interleukin-6 (IL-6), interleukin-8 (IL-8), and interleukin-1ß (IL-1ß)) in LPS-induced THP-1 cells. These results demonstrate that isookanin could be a potential therapeutic candidate for inflammatory disease.

Coptis chinensis Franch Directly Inhibits Proteolytic Activation of Kallikrein 5 and Cathelicidin Associated with Rosacea in Epidermal Keratinocytes.

Rosacea is a common and chronic inflammatory skin disease that is characterized by dysfunction of the immune and vascular system. The excessive production and activation of kallikerin 5 (KLK5) and cathelicidin have been implicated in the pathogenesis of rosacea. Coptis chinensis Franch (CC) has been used as a medicinal herb in traditional oriental medicine. However, little is known about the efficacy and mechanism of action of CC in rosacea. In this study, we evaluate the effect of CC and its molecular mechanism on rosacea in human epidermal keratinocytes. CC has the capacity to downregulate the expression of KLK5 and cathelicidin, and also inhibits KLK5 protease activity, which leads to reduced processing of inactive cathelicidin into active LL-37. It was determined that CC ameliorates the expression of pro-inflammatory cytokines through the inhibition of LL-37 processing. In addition, it was confirmed that chitin, an exoskeleton of Demodex mites, mediates an immune response through TLR2 activation, and CC inhibits TLR2 expression and downstream signal transduction. Furthermore, CC was shown to inhibit the proliferation of human microvascular endothelial cells induced by LL-37, the cause of erythematous rosacea. These results demonstrate that CC improved rosacea by regulating the immune response and angiogenesis, and revealed its mechanism of action, indicating that CC may be a useful therapeutic agent for rosacea.

Inhibitory Effects of Prunella vulgaris L. Extract on 11ß-HSD1 in Human Skin Cells.

Glucocorticoids are a risk factor for age-induced skin structure and function defects, and the glucocorticoid-activating enzyme, 11ß-hydroxysteroid dehydrogenase 1 (11ß-HSD1), represents a promising therapeutic target. Prunella vulgaris L. (PV) is a perennial and an edible herbaceous plant normally cultivated in Asia and Europe. A recent study demonstrated a broad range of biological activities of PV including immune modulatory, antiviral, antiallergic, anti-inflammatory, antioxidant, and antidiabetic. However, little is known about the inhibitory effect of PV on 11ß-HSD1. In this study, we investigated the inhibitory effect of Prunella vulgaris L. extract (PVE) and the underlying mechanism of 11ß-HSD11 inhibition. Consistent with these results, cortisol levels were also reduced by PVE in vitro. The cortisone-induced translocation of glucocorticoids receptor (GR) was also attenuated. In addition, PVE inhibited a cortisone-mediated decrease in collagen content in skin. Collectively, these results suggest the beneficial effects of PVE in maintaining skin integrity.

Oxidative Stress-Protective and Anti-Melanogenic Effects of Loliolide and Ethanol Extract from Fresh Water Green Algae, Prasiola japonica.

Loliolide is a monoterpenoid hydroxylactone found in many algae, including fresh water green algae, Prasiola japonica. To date, loliolide and compounds in P. japonica have not been studied systematically with respect to skin pharmacology. In this study, we investigated oxidative stress-protective and anti-melanogenic effects of loliolide and P. japonica ethanol extract (Pj-EE), known to contain loliolide, in human keratinocyte (HaCaT) cells and mouse melanoma (B16F10) cells. Loliolide suppressed the transcription of genes encoding matrix metalloproteinases (MMPS), which were induced in HaCaT cells by hydrogen peroxide (H2O2) treatment. Loliolide and Pj-EE not only reduced the melanin secretion and content in B16F10 cells but also increased the expression of the antioxidant proteins nuclear factor (erythroid-derived 2)-like 2 (NRF2) and heme oxygenase-1 (HO-1) in HaCaT cells subjected to H2O2 treatment. Furthermore, loliolide and Pj-EE decreased expression of the anti-melanogenic protein microphthalmia-associated transcription factor (MITF) and tyrosinase in B16F10 cells subjected to α-melanocyte-stimulating hormone (α-MSH) treatment. Our findings demonstrate that loliolide and Pj-EE have antioxidant and anti-melanogenic effects on skin.

Anti-inflammatory effects of Zea mays L. husk extracts.

BACKGROUND: Zea mays L. (Z. mays) has been used for human consumption in the various forms of meal, cooking oil, thickener in sauces and puddings, sweetener in processed food and beverage products, bio-disel. However, especially, in case of husk extract of Z. mays, little is known about its anti-inflammatory effects. Therefore, in this study, the anti-inflammatory effects of Z. mays husk extract (ZMHE) and its mechanisms of action were investigated. METHODS: The husks of Z. Mays were harvested in kangwondo, Korea. To assess the anti-inflammatory activities of ZMHE, we examined effects of ZMHE on nitric oxide (NO) production, and release of soluble intercellular adhesion molecule-1 (sICAM-1) and eotaxin-1. The expression level of inducible nitric oxide synthase (iNOS) gene was also determined by Western blot and luciferase reporter assays. To determine its mechanisms of action, a luciferase reporter assay for nuclear factor kappa B (NF-kB) and activator protein-1 (AP-1) was introduced. RESULTS: ZMHE inhibited lipopolysaccharide (LPS)-induced production of NO in RAW264.7 cells. In addition, expression of iNOS gene was reduced, as confirmed by Western blot and luciferase reporter assays. Effects of ZMHE on the AP-1 and NF-kB promoters were examined to elucidate the mechanism of its anti-inflammatory activity. Activation of AP-1 and NF-kB promoters induced by LPS was significantly reduced by ZMHE treatment. In addition, LPS-induced production of sICAM-1 and IL-4-induced production of eotaxin-1 were all reduced by ZMHE. CONCLUSIONS: Our results indicate that ZMHE has anti-inflammatory effects by downregulating the expression of iNOS gene and its downregulation is mediated by inhibiting NF-kB and AP-1 signaling.

Ameliorating Effect of Akebia quinata Fruit Extracts on Skin Aging Induced by Advanced Glycation End Products.

The accumulation of free radicals and advanced glycation end products (AGEs) in the skin plays a very important role in skin aging. Both are known to interact with each other. Therefore, natural compounds or extracts that possess both antioxidant and antiglycation activities might have great antiageing potential. Akebia quinata fruit extract (AQFE) has been used to treat urinary tract inflammatory disease in traditional Korean and Chinese medicines. In the present study, AQFE was demonstrated to possess antioxidant and antiglycation activity. AQFE protects human dermal fibroblasts (HDFs) from oxidative stress and inhibits cellular senescence induced by oxidative stress. We also found that AQFE inhibits glycation reaction between BSA and glucose. The antiglycation activity of AQFE was dose-dependent. In addition, the antiglycation activity of AQFE was confirmed in a human skin explant model. AQFE reduced CML expression and stimulated fibrillin-1 expression in comparison to the methyglyoxal treatment. In addition, the possibility of the extract as an anti-skin aging agent has also been clinically validated. Our analysis of the crow's feet wrinkle showed that there was a decrease in the depth of deep furrows in RI treated with AQFE cream over an eight-week period. The overall results suggest that AQFE may work as an anti-skin aging agent by preventing oxidative stress and other complications associated with AGEs formation.

The Antiaging Properties of Andrographis paniculata by Activation Epidermal Cell Stemness.

Andrographis paniculata (A. paniculata, Chuanxinlian), a medicinal herb with an extremely bitter taste that is native to China and other parts of Southeast Asia, possesses immense therapeutic value; however, its therapeutic properties have rarely been applied in the field of skin care. In this study, we investigated the effect of an A. paniculata extract (APE) on human epidermal stem cells (EpSCs), and confirmed its anti-aging effect through in vitro, ex vivo, and in vivo study. An MTT assay was used to determine cell proliferation. A flow cytometric analysis, with propidium iodide, was used to evaluate the cell cycle. The expression of integrin ß1 (CD29), the stem cell marker, was detected with antibodies, using flow cytometry in vitro, and immunohistochemical assays in ex vivo. Type 1 collagen and VEGF (vascular endothelial growth factor) were measured using an enzyme-linked immunosorbent assay (ELISA). During the clinical study, skin hydration, elasticity, wrinkling, sagging, and dermal density were evaluated before treatment and at four and eight weeks after the treatment with the test product (containing the APE) on the face. The proliferation of the EpSCs, treated with the APE, increased significantly. In the cell cycle analysis, the APE increased the G2/M and S stages in a dose-dependent manner. The expression of integrin ß1, which is related to epidermal progenitor cell expansion, was up-regulated in the APE-treated EpSCs and skin explants. In addition, the production of VEGF in the EpSCs increased significantly in response to the APE treatment. Consistent with these results, the VEGF and APE-treated EpSCs conditioned medium enhanced the Type 1 collagen production in normal human fibroblasts (NHFs). In the clinical study, the APE improved skin hydration, dermal density, wrinkling, and sagging significantly. Our findings revealed that the APE promotes a proliferation of EpSCs, through the up-regulation of the integrin ß1 and VEGF expression. The VEGF might affect the collagen synthesis of NHF as a paracrine factor. Clinical studies further suggested that treatment with formulations containing APE confers anti-aging benefits. Based on these results, we suggest that APE may be introduced as a possible anti-aging agent.

Synephrine inhibits eotaxin-1 expression via the STAT6 signaling pathway.

Citrus contain various flavonoids and alkaloids that have multiple biological activities. It is known that the immature Citrus contains larger amounts of bioactive components, than do the mature plants. Although Citrus flavonoids are well known for their biological activities, Citrus alkaloids have not previously been assessed. In this study, we identified synephrine alkaloids as an active compound from immature Citrus unshiu, and investigated the effect of synephrine on eotaxin-1 expression. Eotaxin-1 is a potent chemoattractant for eosinophils, and a critical mediator, during the development of eosinophilic inflammation. We found that synephrine significantly inhibited IL-4-induced eotaxin-1 expression. This synephrine effect was mediated through the inhibition of STAT6 phosphorylation in JAK/STAT signaling. We also found that eosinophil recruitment induced by eotaxin-1 overexpression was inhibited by synephrine. Taken together, these findings indicate that inhibiting IL-4-induced eotaxin-1 expression by synephrine occurs primarily through the suppression of eosinophil recruitment, which is mediated by inhibiting STAT6 phosphorylation.

Madecassoside inhibits melanin synthesis by blocking ultraviolet-induced inflammation.

Madecassoside (MA), a pentacyclic triterpene isolated from Centella asitica (L.), is used as a therapeutic agent in wound healing and also as an anti-inflammatory and anti-aging agent. However, the involvement of MA in skin-pigmentation has not been reported. This study was conducted to investigate the effects of MA on ultraviolet (UV)-induced melanogenesis and mechanisms in a co-culture system of keratinocytes and melanocytes. MA significantly inhibited UVR-induced melanin synthesis and melanosome transfer in the co-culture system. These effects were further demonstrated by the MA-induced inhibition of protease-activated receptor-2 expression and its signaling pathway, cyclooxygenase-2, prostaglandin E2 and prostaglandin F2 alpha in keratinocytes. The clinical efficacy of MA was confirmed on artificially tanned human skin. MA significantly reduced UV-induced melanin index at 8 weeks after topical application. Overall, the study demonstrated significant benefits of MA use in the inhibition of hyperpigmentation caused by UV irradiation.

Fumaric acid attenuates the eotaxin-1 expression in TNF-α-stimulated fibroblasts by suppressing p38 MAPK-dependent NF-κB signaling.

Eotaxin-1 is a potent chemoattractant for eosinophils and a critical mediator during the development of eosinophilic inflammation. Fumaric acid is an intermediate product of the citric acid cycle, which is source of intracellular energy. Although fumaric acid ameliorates psoriasis and multiple sclerosis, its involvement in eotaxin-1-mediated effects has not been assessed. In this study, we investigated the effects of fumaric acid on eotaxin-1 expression in a mouse fibroblast cell line. We found that fumaric acid significantly inhibited tumor necrosis factor-α (TNF-α-induced eotaxin-1 expression. This fumaric acid effect was mediated through the inhibition of p38 mitogen-activated protein kinase (MAPK)-dependent nuclear factor (NF)-κB signaling. We also found that fumaric acid operates downstream of MEKK3 during TNF-α-induced NF-κB signaling, which upregulated eotaxin-1 expression. In addition, fumaric acid attenuated expression of CC-chemokine receptor 3 (CCR3), an eotaxin-1 receptor, and adhesion molecules that play important roles in eosinophil binding to induce allergic inflammation. Taken together, these findings indicate that inhibiting TNF-α-induced eotaxin-1 expression by fumaric acid occurs primarily through suppression of NF-κB signaling, which is mediated by inhibiting p38 MAPK and suggest that fumaric acid may be used as a complementary treatment option for eotaxin-1-mediated diseases.

Soy peptide-induced stem cell proliferation: involvement of ERK and TGF-ß1.

This study was conducted to investigate the proliferative effect of vegetable soy peptides on adult stem cells (ASCs) in the absence of serum and their possible mechanisms of action. The proliferation of human adipose tissue-derived mesenchymal stem cells (ADSCs) and cord blood-derived mesenchymal stem cells (CB-MSCs) treated with soy peptides was found to increase significantly upon 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide and Click-iT 5-ethynyl-2'-deoxyuridine flow cytometry assay. In addition, soy peptides led to stepwise phosphorylation of the p44/42 MAPK (ERK), mammalian target of rapamycin (mTOR), p70 S6 kinase, S6 ribosomal protein (S6RP) and eukaryotic initiation factor 4E (eIF4E) in ADSCs. Furthermore, quantitative analysis of the cytokines revealed that the production of transforming growth factor-beta1 (TGF-ß1), vascular endothelial growth factor and interleukin-6 increased significantly in response to treatment with soy peptides in both ADSCs and CB-MSCs. Similarly, soy peptide-induced phosphorylation of the ERK/mTOR/S6RP/eIF4E pathway was blocked in response to pretreatment with PD98059, a specific ERK inhibitor. Moreover, inhibition of TGF-ß1 through PD98059 pretreatment and a consecutive decrease in ADSC proliferation revealed that TGF-ß1 induces the phosphorylation of mTOR/S6RP/eIF4E. Collectively, the results of this study indicate that ERK-dependent production of TGF-ß1 plays a crucial role in the soy peptide-induced proliferation of ADSCs under serum-free conditions.

Mechanisms of Edible Bird's Nest Extract-Induced Proliferation of Human Adipose-Derived Stem Cells.

Although edible bird's nest (EBN) has been shown to potentiate mitogenic responses, scientific evidence of its efficacy is still limited. In addition, human adipose-derived stem cells (hADSCs) are increasingly accepted as a source for stem cell therapy. Therefore, the aim of this study was to investigate the effects of the EBN extract (EBNE) on the proliferation of hADSCs and its action mechanisms. We found that EBNE strongly promoted the proliferation of hADSCs. In addition, EBNE-induced proliferation was found to be mediated through the production of IL-6 and VEGF, which was induced by activation of AP-1 and NF-κB. Specially, we found that production of IL-6 and VEGF was induced by EBNE. In addition, EBNE-induced production of IL-6 and VEGF was inhibited by PD98059 (a p44/42 MAPK inhibitor), SB203580 (a p38 MAPK inhibitor), and PDTC (a NF-κB inhibitor), but not SP600125 (a JNK inhibitor). Similarly, EBNE-induced proliferation of hADSCs was also attenuated by PD98059, SB203580, and PDTC but not SP600125. Taken together, these findings suggest that the EBNE-induced proliferation of hADSCs primarily occurs through increased expression of IL-6 and VEGF genes, which is mediated by the activation of NF-κB and AP-1 through p44/42 MAPK and p38 MAPK.

Proteolytic cascade for the activation of the insect toll pathway induced by the fungal cell wall component.

The insect Toll signaling pathway is activated upon recognition of Gram-positive bacteria and fungi, resulting in the expression of antimicrobial peptides via NF-kappaB-like transcription factor. This activation is mediated by a serine protease cascade leading to the processing of Spätzle, which generates the functional ligand of the Toll receptor. Recently, we identified three serine proteases mediating Toll pathway activation induced by lysine-type peptidoglycan of Gram-positive bacteria. However, the identities of the downstream serine protease components of Gram-negative-binding protein 3 (GNBP3), a receptor for a major cell wall component beta-1,3-glucan of fungi, and their order of activation have not been characterized yet. Here, we identified three serine proteases that are required for Toll activation by beta-1,3-glucan in the larvae of a large beetle, Tenebrio molitor. The first one is a modular serine protease functioning immediately downstream of GNBP3 that proteolytically activates the second one, a Spätzle-processing enzyme-activating enzyme that in turn activates the third serine protease, a Spätzle-processing enzyme. The active form of Spätzle-processing enzyme then cleaves Spätzle into the processed Spätzle as Toll ligand. In addition, we show that injection of beta-1,3-glucan into Tenebrio larvae induces production of two antimicrobial peptides, Tenecin 1 and Tenecin 2, which are also inducible by injection of the active form of Spätzle-processing enzyme-activating enzyme or processed Spätzle. These results demonstrate a three-step proteolytic cascade essential for the Toll pathway activation by fungal beta-1,3-glucan in Tenebrio larvae, which is shared with lysine-type peptidoglycan-induced Toll pathway activation.

The Triacylated ATP Binding Cluster Transporter Substrate-binding Lipoprotein of Staphylococcus aureus Functions as a Native Ligand for Toll-like Receptor 2.

Some synthetic lipopeptides, in addition to native lipoproteins derived from both Gram-negative bacteria and mycoplasmas, are known to activate TLR2 (Toll-like receptor 2). However, the native lipoproteins inherent to Gram-positive bacteria, which function as TLR2 ligands, have not been characterized. Here, we have purified a native lipoprotein to homogeneity from Staphylococcus aureus to study as a native TLR2 ligand. The purified 33-kDa lipoprotein was capable of stimulating TLR2 and was identified as a triacylated SitC lipoprotein, which belongs to a family of ATP binding cluster (ABC) transporter substrate-binding proteins. Analyses of the SitC-mediated production of cytokine using mouse peritoneal macrophages revealed that the SitC protein (3 nm) induced the production of tumor necrosis factor-alpha and interleukin-6. Moreover, analysis of knock-out mice showed that SitC required TLR2 and MyD88, but not TLR1 or TLR6, for the induction of cytokines. In addition to the S. aureus SitC lipoprotein, we purified two other native ABC transporter substrate-binding lipoproteins from Bacillus subtilis and Micrococcus luteus, which were both shown to stimulate TLR2. These results demonstrate that S. aureus SitC lipoprotein is triacylated and that the ABC transporter substrate-binding lipoproteins of Gram-positive bacteria function as native ligands for TLR2.

Molecular control of phenoloxidase-induced melanin synthesis in an insect.

The melanization reaction induced by activated phenoloxidase in arthropods must be tightly controlled because of excessive formation of quinones and excessive systemic melanization damage to the hosts. However, the molecular mechanism by which phenoloxidase-induced melanin synthesis is regulated in vivo is largely unknown. It is known that the Spätzle-processing enzyme is a key enzyme in the production of cleaved Spätzle from pro-Spätzle in the Drosophila Toll pathway. Here, we provide biochemical evidence that the Tenebrio molitor Spätzle-processing enzyme converts both the 79-kDa Tenebrio prophenoloxidase and Tenebrio clip-domain SPH1 zymogen to an active melanization complex. This complex, consisting of the 76-kDa Tenebrio phenoloxidase and an active form of Tenebrio clip-domain SPH1, efficiently produces melanin on the surface of bacteria, and this activity has a strong bactericidal effect. Interestingly, we found the phenoloxidase-induced melanization reaction to be tightly regulated by Tenebrio prophenoloxidase, which functions as a competitive inhibitor of melanization complex formation. These results demonstrate that the Tenebrio Toll pathway and the melanization reaction share a common serine protease for the regulation of these two major innate immune responses.

A three-step proteolytic cascade mediates the activation of the peptidoglycan-induced toll pathway in an insect.

The recognition of lysine-type peptidoglycans (PG) by the PG recognition complex has been suggested to cause activation of the serine protease cascade leading to the processing of Spätzle and subsequent activation of the Toll signaling pathway. So far, two serine proteases involved in the lysine-type PG Toll signaling pathway have been identified. One is a modular serine protease functioning as an initial enzyme to be recruited into the lysine-type PG recognition complex. The other is the Drosophila Spätzle processing enzyme (SPE), a terminal enzyme that converts Spätzle pro-protein to its processed form capable of binding to the Toll receptor. However, it remains unclear how the initial PG recognition signal is transferred to Spätzle resulting in Toll pathway activation. Also, the biochemical characteristics and mechanism of action of a serine protease linking the modular serine protease and SPE have not been investigated. Here, we purified and cloned a novel upstream serine protease of SPE that we named SAE, SPE-activating enzyme, from the hemolymph of a large beetle, Tenebrio molitor larvae. This enzyme was activated by Tenebrio modular serine protease and in turn activated the Tenebrio SPE. The biochemical ordered functions of these three serine proteases were determined in vitro, suggesting that the activation of a three-step proteolytic cascade is necessary and sufficient for lysine-type PG recognition signaling. The processed Spätzle by this cascade induced antibacterial activity in vivo. These results demonstrate that the three-step proteolytic cascade linking the PG recognition complex and Spätzle processing is essential for the PG-dependent Toll signaling pathway.