In Vitro Anti-Rotaviral Activity of Bavachin Isolated from Psoralea corylifolia L. (Fabaceae).

Rotavirus is the main causative agent of viral gastroenteritis among young animals worldwide. Currently, no clinically approved or effective antiviral drugs are available to combat rotavirus infections. Herein, we evaluated the anti-rotaviral activities of extracts and bavachin isolated from Psoralea corylifolia L. (Fabaceae) (P. corylifolia) against the bovine rotavirus G8P[7] and porcine rotavirus G5P[7] in vitro. Two assay strategies were performed: (1) a virucidal assay to reduce viral infectivity by virus neutralization and (2) a post-treatment assay to assess viral replication suppression. The results from the virucidal assay showed that the extracts and bavachin did not exert anti-rotaviral activities. In the follow-up analysis after treatment, bavachin exhibited robust antiviral efficacy, with 50% effective concentration (EC50) values of 10.6 µM (selectivity index [SI] = 2.38) against bovine rotavirus G8P[7] and 13.0 µM (SI = 1.94) against porcine rotavirus G5P[7]. Bavachin strongly suppressed viral RNA synthesis in the early (6 h) and late stages (18 h) after rotaviral infection. These findings strongly suggest that bavachin may have hindered the virions by effectively inhibiting the early stages of the virus replication cycle after rotaviral infection. Furthermore, confocal imaging showed that bavachin suppressed viral protein synthesis, notably that of the rotaviral protein (VP6). These results suggest that bavachin has strong antiviral activity against rotaviruses, inhibits viral replication, and is a candidate natural therapeutic drug targeting rotaviral infection. The utilization of bavachin isolated from P. corylifolia may contribute to decreased mortality rates, lower medication expenses, and enhanced economic viability in domestic farms.

Ferulic Acid Derivatives Ameliorate Intestine Barrier Destruction by Alleviating Inflammatory Responses in Dextran Sulfate Sodium-Induced Inflammatory Bowel Disease.

Inflammatory bowel disease (IBD), a chronic disorder affecting the colon and rectum, involves the overproduction of pro-inflammatory cytokines causing damage to tight junctions (TJ) in the intestinal epithelial cells and chronic inflammation. The current mainstay of treatment, sulfasalazine, often causes adverse effects, thereby necessitating the exploration of alternative herbal medicines with fewer side effects. Portulaca oleracea L. (P. oleracea), a traditional medicinal herb, contains feruloyl amide compounds. We synthesized new compounds by conjugating ferulic acid (FA) with (±)-octopamine. Our study focused on novel FA derivatives that demonstrate protective effects against the intestinal epithelial barrier and inflammatory responses. In lipopolysaccharide-induced cells, C1 and C1a inhibited the production of inflammatory mediators. In Caco-2 cells, these compounds maintained the TJ protein expression, thereby demonstrating their protective effects on the epithelial barrier. In a mouse model of dextran sulfate sodium-induced IBD, a treatment with these compounds ameliorated features including a body weight reduction, colon shortening, an increased disease activity index, and histopathological changes. Furthermore, C1a demonstrated greater efficacy than C1 at the same concentration. These findings suggest that the novel FA derivative (C1a) effectively alleviates clinical signs and inflammatory mediators in IBD, making these compounds potential candidates as natural medicines for the treatment of IBD.

Oleanolic Acid Acetate Alleviates Cisplatin-Induced Nephrotoxicity via Inhibition of Apoptosis and Necroptosis In Vitro and In Vivo.

Cisplatin is a widely used anti-cancer drug for treating solid tumors, but it is associated with severe side effects, including nephrotoxicity. Various studies have suggested that the nephrotoxicity of cisplatin could be overcome; nonetheless, an effective adjuvant drug has not yet been established. Oleanolic acid acetate (OAA), a triterpenoid isolated from Vigna angularis, is commonly used to treat inflammatory and allergic diseases. This study aimed to investigate the protective effects of OAA against cisplatin-induced apoptosis and necroptosis using TCMK-1 cells and a mouse model. In cisplatin-treated TCMK-1 cells, OAA treatment significantly reduced Bax and cleaved-caspase3 expression, whereas it increased Bcl-2 expression. Moreover, in a cisplatin-induced kidney injury mouse model, OAA treatment alleviated weight loss in the body and major organs and also relieved cisplatin-induced nephrotoxicity symptoms. RNA sequencing analysis of kidney tissues identified lipocalin-2 as the most upregulated gene by cisplatin. Additionally, necroptosis-related genes such as receptor-interacting protein kinase (RIPK) and mixed lineage kinase domain-like (MLKL) were identified. In an in vitro study, the phosphorylation of RIPKs and MLKL was reduced by OAA pretreatment in both cisplatin-treated cells and cells boosted via co-treatment with z-VAD-FMK. In conclusion, OAA could protect the kidney from cisplatin-induced nephrotoxicity and may serve as an anti-cancer adjuvant.

Ethanol Extract of Ampelopsis brevipedunculata Rhizomes Suppresses IgE-Mediated Mast Cell Activation and Anaphylaxis.

More than 20% of the world's population suffers from allergic diseases, including allergic asthma, rhinitis, and atopic dermatitis that severely reduce the patient's quality of life. The treatment of allergy has been developed, but there are still unmet needs. Ampelopsis brevipedunculata (Maxim.) Trautv. is a traditional medicinal herb with beneficial bioactivities, such as antioxidant, anti-hypertension, anti-viral, anti-mutagenic, and skin and liver (anti-hepatotoxic) protective actions. However, its anti-allergic effect has not been addressed. This study designed to investigate the pharmacological effect of an ethanol extract of A. brevipedunculata rhizomes (ABE) on mast cell and anaphylaxis models. For in vivo studies, we used ovalbumin-induced active systemic anaphylaxis (ASA) and immunoglobulin (Ig) E-mediated passive cutaneous anaphylaxis (PCA) models. In ASA model, oral administration of ABE (1, 10, and 100 mg/kg) attenuated the anaphylactic responses, such as hypothermia, serum histamine, and IgE productions. In PCA model, ABE also suppressed the plasma extravasation and swelling. The underlying mechanisms of action were identified in various mast cell types. In vitro, ABE (10, 30, and 60 µg/mL) inhibited the release of essential allergic mediators, such as histamine and ß-hexosaminidase, in a concentration-dependent manner. ABE prevented the rapid increase in intracellular calcium levels induced by the DNP-HSA challenge. In addition, ABE downregulated the tumor necrosis factor-α and interleukin-4 by suppressing the activation of nuclear factor-κB. Collectively, this study is the first to identify the anti-allergic effect of ABE, suggesting that ABE is a promising candidate for treating allergic diseases.

Bakuchicin alleviates ovalbumin-induced allergic asthma by regulating M2 macrophage polarization.

OBJECTIVE: Asthma is an airway inflammatory disease caused by activation of numerous immune cells including macrophages. Bakuchicin (BKC) is known to exhibit anti-inflammatory effects and type 2 T helper (Th2) regulation, but has not been investigated for airway inflammation. This study aimed to evaluate the effects of BKC on airway inflammation and demonstrate the mechanisms of macrophage polarization. METHODS: The anti-inflammatory effects were determined using lipopolysaccharide (LPS)-stimulated macrophages. The ovalbumin (OVA)-induced asthma mouse model was used to evaluate the effects of BKC on airway inflammation and Th2 responses. Moreover, the effect of BKC on macrophage polarization was confirmed in bone marrow-derived macrophages (BMDMs) differentiation. RESULTS: BKC suppressed nitric oxide production and expression of pro-inflammatory cytokines by inhibiting signaling pathway in LPS-stimulated macrophages. In an OVA-induced asthma model, BKC treatment alleviated histological changes and mast cell infiltration and reduced the levels of eosinophil peroxidase, ß-hexosaminidase, and immunoglobulin levels. In addition, BKC alleviated Th2 responses and M2 macrophage populations in bronchoalveolar fluid. In BMDMs, BKC suppressed IL-4-induced M2 macrophage polarization and the expression of M2 markers such as arginase-1 and Fizz-1 through inhibiting sirtuin 2 levels. CONCLUSION: BKC could be a drug candidate for the treatment of allergic asthma.

Effect of Ampelopsis brevipedunculata (Maxim.) Trautv extract on a model of atopic dermatitis in HaCaT cells and mice.

Ampelopsis brevipedunculata (Maxim.) Trautv. has been used for a long time as a folk remedy. According to studies, it possesses anti-inflammatory, antioxidant, and antibacterial properties. However, its effects on atopic dermatitis (AD) are poorly studied. Thus, we investigated the therapeutic effect of A. brevipedunculata (Maxim.) Trautv. extract (ABE-M) on 2,4-dinitrochlorobenzene (DNCB)-induced AD. For in vitro analysis, keratinocytes cell lines (HaCaT cells) were used. To evaluate the gene and protein expression levels of cytokines and chemokines, TNF-α/IFN-γ-stimulated HaCaT cells were treated with ABE-M. The cells and the supernatant were collected, then gene and protein levels were analyzed by real-time polymerase chain reaction and enzyme-linked immunosorbent assay analysis. For in vivo analysis, BALB/c mice (6 weeks) were randomly separated into five groups (n = 5). The mice were applied DNCB and phosphate-buffered saline, dexamethasone (DX) or ABE-M (50, 100, and 200 mg/kg) was orally administrated for 28 days. At the end, ear tissues and blood were collected for histological analysis and evaluation of cytokines and chemokines. In keratinocytes, ABE-M inhibited the protein and mRNA levels of chemokines, and cytokines exposed by TNF-α/IFN-γ. Similarly, the expression of chemokines was suppressed by ABE-M in AD animal model induced by DNCB and the level of pro-inflammatory cytokines was decreased in a dose-dependent manner. Our research indicates that ABE-M could be a candidate material that can be used to improve skin immunity enhancement, health, and beauty.

Effects of Vigna angularis extract and its active compound hemiphloin against atopic dermatitis-like skin inflammation.

Vigna angularis is an edible crop and herbal medicine that is known to have antipyretic, anti-inflammatory, and anti-edema effects. Many studies have been conducted on the 95% ethanol extract of V. angularis, but there is little research on the 70% ethanol extract and hemiphloin, which is a new indicator component of the 70% ethanol extract of V. angularis. To investigate the in vitro anti-atopic effect and verify the mechanism action of 70% ethanol extract of V. angularis (VAE), TNF-α/IFN-γ-induced HaCaT keratinocytes were used. The VAE treatment alleviated TNF-α/IFN-γ-induced IL-1ß, IL-6, IL-8, CCL17/TARC, and CCL22/MDC gene expressions and productions. VAE also inhibited the phosphorylation of MAPKs, including p38, ERK, JNK, STAT1, and NF-κB in TNF-α/IFN-γ-induced HaCaT cells. 2,4-dinitochlorobenzene (DNCB)-induced skin inflammation mice model, and HaCaT keratinocytes were used. In the DNCB-induced mouse model, VAE treatment alleviated ear thicknesses and IgE levels. Furthermore, VAE decreased IL-1ß, IL-6, IL-8, CCL17/TARC, and CCL22/MDC gene expressions of DNCB-applied ear tissue. Additionally, we investigated the anti-atopic and anti-inflammatory effects of hemiphloin using TNF-α/IFN-γ-induced HaCaT keratinocytes and LPS-induced J774 macrophages. Treatment hemiphloin decreased gene expressions and productions of IL-1ß, IL-6, IL-8, CCL17/TARC, and CCL22/MDC in TNF-α/IFN-γ-induced HaCaT cells. The phosphorylations of p38, ERK, STAT1, and NF-κB were inhibited by hemiphloin in TNF-α/IFN-γ-induced HaCaT cells. Finally, hemiphloin showed anti-inflammatory activities in LPS-induced J774 cells. It decreased LPS-induced NO productions and iNOS and COX-2 expressions. Treatment of hemiphloin also inhibited LPS-induced TNF-α, IL-1ß, and IL-6 gene expressions. These results suggest that VAE is an anti-inflammatory agent for inflammatory skin diseases and that hemiphloin could be a therapeutic candidate for inflammatory skin diseases.

Regulatory Effects of Lycium barbarum Extract and Isolated Scopoletin on Atopic Dermatitis-Like Skin Inflammation.

Lycium barbarum and scopoletin are widely used in oriental Eastern medicine and are often consumed as teas. In this study, proinflammatory cytokines expressed in human keratinocytes (HaCaT) were induced by skin diseases caused by 2,4-dinitrochlorobenzene (DNCB) and tumor necrosis factor alpha (TNF-α)/interferon gamma (IFN-γ). The inhibitory activity of L. barbarum EtOH extract (LBE) and scopoletin on proinflammatory cytokines and chemokines was investigated. In the DNCB-induced animal model, oral administration of LBE inhibited skin lesions and proinflammatory cytokines and chemokines and showed inhibitory effects in vitro. Additionally, as a result of examining the efficacy of scopoletin isolated from L. barbarum, scopoletin in HaCaT cells showed inhibitory effects on proinflammatory cytokines and chemokines. It shows promise in the treatment of chronic skin diseases.

Anti-Osteoporotic Effects of n-trans-Hibiscusamide and Its Derivative Alleviate Ovariectomy-Induced Bone Loss in Mice by Regulating RANKL-Induced Signaling.

Osteoporosis is characterized by the deterioration of bone structures and decreased bone mass, leading to an increased risk of fracture. Estrogen deficiency in postmenopausal women and aging are major factors of osteoporosis and are some of the reasons for reduced quality of life. In this study, we investigated the effects of n-trans-hibiscusamide (NHA) and its derivative 4-O-(E)-feruloyl-N-(E)-hibiscusamide (HAD) on receptor activator of nuclear factor kappa-Β (NF-κB) ligand (RANKL)-induced osteoclast differentiation and an ovariectomized osteoporosis mouse model. NHA and HAD significantly inhibited the differentiation of osteoclasts from bone marrow-derived macrophages (BMMs) and the expression of osteoclast differentiation-related genes. At the molecular level, NHA and HAD significantly downregulated the phosphorylation of mitogen-activated protein kinase (MAPK) signaling molecules. However, Akt and NF-κB phosphorylation was inhibited only after NHA or HAD treatment. In the ovariectomy (OVX)-induced osteoporosis model, both NHA and HAD effectively improved trabecular bone structure. C-terminal telopeptide (CTX), a bone resorption marker, and RANKL, an osteoclast stimulation factor, were significantly reduced by NHA and HAD. The tartrate-resistant acid phosphatase (TRAP)-stained area, which indicates the osteoclast area, was also decreased by these compounds. These results show the potential of NHA and HAD as therapeutic agents for osteoporosis.

Eudebeiolide B Inhibits Osteoclastogenesis and Prevents Ovariectomy-Induced Bone Loss by Regulating RANKL-Induced NF-κB, c-Fos and Calcium Signaling.

Eudebeiolide B is a eudesmane-type sesquiterpenoid compound isolated from Salvia plebeia R. Br., and little is known about its biological activity. In this study, we investigated the effects of eudebeiolide B on osteoblast differentiation, receptor activator nuclear factor-κB ligand (RANKL)-induced osteoclastogenesis in vitro and ovariectomy-induced bone loss in vivo. Eudebeiolide B induced the expression of alkaline phosphatase (ALP) and calcium accumulation during MC3T3-E1 osteoblast differentiation. In mouse bone marrow macrophages (BMMs), eudebeiolide B suppressed RANKL-induced osteoclast differentiation of BMMs and bone resorption. Eudebeiolide B downregulated the expression of nuclear factor of activated T-cells 1 (NFATc1) and c-fos, transcription factors induced by RANKL. Moreover, eudebeiolide B attenuated the RANKL-induced expression of osteoclastogenesis-related genes, including cathepsin K (Ctsk), matrix metalloproteinase 9 (MMP9) and dendrocyte expressed seven transmembrane protein (DC-STAMP). Regarding the molecular mechanism, eudebeiolide B inhibited the phosphorylation of Akt and NF-κB p65. In addition, it downregulated the expression of cAMP response element-binding protein (CREB), Bruton's tyrosine kinase (Btk) and phospholipase Cγ2 (PLCγ2) in RANKL-induced calcium signaling. In an ovariectomized (OVX) mouse model, intragastric injection of eudebeiolide B prevented OVX-induced bone loss, as shown by bone mineral density and contents, microarchitecture parameters and serum levels of bone turnover markers. Eudebeiolide B not only promoted osteoblast differentiation but inhibited RANKL-induced osteoclastogenesis through calcium signaling and prevented OVX-induced bone loss. Therefore, eudebeiolide B may be a new therapeutic agent for osteoclast-related diseases, including osteoporosis, rheumatoid arthritis and periodontitis.

Beneficial effects of Vigna angularis extract in osteoporosis and osteoarthritis.

In Asia, Vigna angularis (azuki bean) has been used as a traditional medicine to treat various diseases because of its biological properties. Osteoarthritis (OA) and osteoporosis (OP) are common regenerative bone diseases that are characterized by deterioration of joint and bone structure. In this study, we evaluated the effects of Vigna angularis extract (VAE) on monosodium iodoacetate (MIA)-induced OA and ovariectomy (OVX)-induced OP models. In the MIA-induced OA results, severe OA was alleviated by the administration of VAE. Extensive local damage in the cartilage and hemorrhagic and edematous of surrounding tissues were decreased by VAE treatment. Articular cartilage was almost intact except for a focal mild abrasion, and the surface was glistening, similar to that of the normal joint. In the OVX-induced OP results, bone mineral content (BMC) and bone mineral density (BMD) were recovered by VAE treatment, and it improved the microstructures of bone. These results show that VAE could inhibit OA and OP symptoms.

Retrofractamide C Derived from Piper longum Alleviates Xylene-Induced Mouse Ear Edema and Inhibits Phosphorylation of ERK and NF-κB in LPS-Induced J774A.1.

Many studies have reported the biological activities of retrofractamide C (RAC). However, few studies have investigated the anti-inflammatory effect of RAC. In the present study, we investigated the anti-inflammatory effect of RAC using lipopolysaccharide (LPS)-induced J774A.1 cells and a xylene-induced mouse ear edema model. Treatment with RAC decreased LPS-induced nitric oxide (NO) and prostaglandin E2 (PGE2) secretion and inducible NO synthase (iNOS) and cyclooxygenase 2 (COX2) protein expression. It also downregulated the LPS-induced production of interleukin-1ß (IL-1ß) and interleukin-6 (IL-6) but not tumor necrosis factor α (TNF-α). In the LPS-induced signaling pathway, RAC inhibited the phosphorylation of extracellular signal-regulated kinase (ERK) and nuclear factor kappa light chain enhancer of activated B cells (NF-κB) but not c-Jun N-terminal kinase (JNK) or p38. In a xylene-induced mouse ear edema model, RAC treatment alleviated edema formation and inflammatory cell infiltration. In conclusion, the present study indicates that RAC has the potential to have anti-inflammatory effects and could be a prospective functional food.

Anti-Inflammatory Activity of Diterpenoids from Celastrus orbiculatus in Lipopolysaccharide-Stimulated RAW264.7 Cells.

Celastrus orbiculatus Thunb has been known as an ethnopharmacological medicinal plant for antitumor, anti-inflammatory, and analgesic effects. Although various pharmacological studies of C. orbiculatus extract has been reported, an anti-inflammatory mechanism study of their phytochemical constituents has not been fully elucidated. In this study, compounds 1-17, including undescribed podocarpane-type trinorditerpenoid (3), were purified from C. orbiculatus and their chemical structure were determined by high-resolution electrospray ionization mass (HRESIMS) and nuclear magnetic resonance (NMR) spectroscopic data. To investigate the anti-inflammatory activity of compounds 1-17, nitric oxide (NO) secretion was evaluated in LPS-treated murine macrophages, RAW264.7 cells. Among compounds 1-17, deoxynimbidiol (1) and new trinorditerpenoid (3) showed the most potent inhibitory effects (IC50: 4.9 and 12.6 µM, respectively) on lipopolysaccharide- (LPS-) stimulated NO releases as well as proinflammatory mediators, such as inducible nitric oxide (iNOS), cyclooxygenase- (COX-) 2, interleukin- (IL-) 1ß, IL-6, and tumor necrosis factor- (TNF-) α. Its inhibitory activity of proinflammatory mediators is contributed by suppressing the activation of nuclear transcription factor- (NF-) κB and mitogen-activated protein kinase (MAPK) signaling cascades including p65, inhibition of NF-κB (IκB), extracellular signal-regulated kinase (ERK), c-Jun NH2-terminal kinase (JNK), and p38. Therefore, these results demonstrated that diterpenoids 1 and 3 obtained from C. orbiculatus may be considered a potential candidate for the treatment of inflammatory diseases.

Rugosic acid A, derived from Rosa rugosa Thunb., is novel inhibitory agent for NF-κB and IL-6/STAT3 axis in acute lung injury model.

Rosa rugosa Thunb., is as a medicinal plant known for anti-diabetic, and anti-inflammatory activities. However, the specific active compounds responsible for the individual pharmacological effects of in R. rugosa extract (95% EtOH) remain unknown. Here, we hypothesized that terpenoid structure, the most abundant constituents in R. rugosa extract, are responsible for its anti-inflammatory activity. We investigated the phytochemical substituents (compounds 1-13) and newly purified 11-methoxy polisin A, and 13-methoxy bisaborosaol F using NMR and ESI-MS and to screened their effects on NO production in LPS-induced macrophages. Rugosic acid A (RA) induced to ameliorate NO production, iNOS, and pro-inflammatory cytokines associated with the NF-κB. And, RA suppressed IL-6 secretion and IL-6-mediated STAT3 activation in LPS-mediated inflammation. In addition, RA was evaluated in LPS-mediated acute lung injury (ALI) model similar to acute pneumonia. Our results suggested that RA was suppressed to translocate nuclear NF-κB and IL-6-mediated STAT3 activation. Finally, RA led to amelioration of ALI by decreasing myeloperoxidase (MPO) and inhibiting phosphorylation of NF-κB and STAT3. Our group originally found that R. rugosa extract had new methoxy compounds and RA may be alternative natural agent for acute pneumonia similar to severe acute respiratory syndrome by coronavirus.

Acyclic Triterpenoid Isolated from Alpinia katsumadai Alleviates Formalin-Induced Chronic Mouse Paw Inflammation by Inhibiting the Phosphorylation of ERK and NF-κB.

Chronic and excessive inflammation can destroy host organs and cause inflammatory diseases such as inflammatory bowel disease, asthma, and rheumatoid arthritis. In this study, we investigated the anti-inflammatory effects of Alpinia katsumadai seed-derived 2,3,5,22,23-pentahydroxy-2,6,10,15,19,23-hexamethyl-tetracosa-6,10,14,18-tetraene (PHT) using lipopolysaccharide (LPS)-stimulated J774 cells and a formalin-induced chronic paw inflammation mouse model. The in vitro results showed that PHT exhibited no cytotoxicity and decreased LPS-induced NO secretion. Additionally, PHT inhibited LPS-induced inducible NO synthase (iNOS) and cyclooxygenase 2 (COX2) protein expression. The quantitative real-time PCR results showed that PHT downregulated the gene expression of the proinflammatory cytokines interleukin-1ß (IL-1ß) and interleukin-6 (IL-6) but not tumor necrosis factor α (TNF-α). PHT inhibited the LPS-induced phosphorylation of extracellular signal-regulated kinase (ERK) and nuclear factor kappa light chain enhancer of activated B cells (NF-κB). In a mouse model, oral administration of 50 mg/kg PHT significantly alleviated both mouse paw thickness and volume. These results indicate that PHT has potential anti-inflammatory effects and should be considered a possible functional material.

Evaluation of Nematicidal Activity of Streptomyces yatensis KRA-28 against Meloidogyne incognita.

The root-knot nematode (Meloidogyne incognita) is an important pathogen in crop cultivation, however, few methods are available to control this parasitic roundworm. In this study, the nematicidal effects of approximately 30 Streptomyces strains isolated from soil samples of Mt. Naejang (Korea) were tested against Meloidogyne incognita, and the culture broth of the strains KRA- 24 and KRA-28 exhibited approximately 75% and 85% insecticidal activity, respectively, in in vitro assays. In in vivo pot experiments, these strains reduced the number of nematodes in the soil and the number of egg masses in the roots of red peppers. The two strains also survived in the presence of insecticidal agents (0.1 to 3.0%) such as fosthiazate, ethoprophos and terbufos when they were used in parallel. The mixture of KRA-24 or KRA-28 culture broth and fosthiazate exhibited nematicidal effects that were similar to those observed when KRA-24 or KRA-28 were used alone. Our results clearly suggest that the Streptomyces strains KRA-24 and KRA-28 should be promoted as a biocontrol agent against Meloidogyne incognita.

AGK2 ameliorates mast cell-mediated allergic airway inflammation and fibrosis by inhibiting FcεRI/TGF-ß signaling pathway.

Asthma is characterized by airway hyperresponsiveness and allergic inflammation, detrimentally affecting the patients' quality of life. The development of new drugs for the treatment of asthma is warranted to alleviate these issues. Recent studies have demonstrated that sirtuin2 (SIRT2) aggravates asthmatic inflammation by up-regulation of T-helper type 2 responses and macrophage polarization. However, effects of SIRT2 on mast cell activation remain obscure. In this study, we investigated the effects of AGK2, an inhibitor for SIRT2, on mast cell-mediated allergic airway inflammation. Pre-treatment with AGK2 inhibited degranulation of mast cells by suppressing the FcεRI signaling pathway and intracellular calcium influx. The expression of pro-inflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, IL-4, IL-5, IL-6, and IL-8, was inhibited via regulation of transcription factors such as NF-κB and NRF2. These effects of AGK2 were verified in passive cutaneous anaphylaxis and acute lung injury animal models. AGK2 attenuated Evans blue pigmentation by inhibiting mast cell activation and lung barrier dysfunction by inhibiting inflammatory responses in these animal models. In the ovalbumin (OVA)-induced allergic airway inflammation murine model, AGK2 alleviated allergic asthma symptoms such as lung histological changes (immune cell and mast cell infiltration, collagen deposition, and α-smooth muscle actin expression) and serum immunoglobulins (Ig) levels (IgE, OVA-specific IgE, IgG1, and IgG2a). Moreover, AGK2 reduced the levels of pro-inflammatory cytokines (TNF-α, IL-1ß, IL-4, IL-5, and IL-6) and inflammatory mediators (myeloperoxidase, eosinophil peroxidase, and tumor growth factor-α) in the bronchoalveolar lavage fluid and lung tissues. In addition, the anti-fibrotic effects of AGK2 were verified using lung epithelial cells and TGF-ß/Smad reporter stable cells. In conclusion, our findings suggest that SIRT2 plays a role in mast cell-mediated airway inflammatory disease. Therefore, AGK2 is a good potential candidate for treating allergic asthma and lung inflammation.

Cynanchum atratum Ameliorates Airway Inflammation via Maintaining Alveolar Barrier and Regulating Mast Cell-Mediated Inflammatory Responses.

Asthma is a common allergic airway inflammatory disease, characterized by abnormal breathing due to bronchial inflammation. Asthma aggravates the patient's quality of life and needs continuous pharmacological treatment. Therefore, discovery of drugs for the treatment of asthma is an important area of human health. The aim of the present study was to evaluate whether Cynanchum atratum extract (CAE) modulates the asthma-like allergic airway inflammation and to study its possible mechanism of action using ovalbumin (OVA)-induced airway inflammation and lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice, as well as a mast cell-based in vitro model. The histological analysis showed that CAE reduced the airway constriction and immune cell infiltration. CAE also inhibited release of ß-hexosaminidase and expression of inflammatory cytokines such as tumor necrosis factor (TNF)-α, interleukin (IL)-4, and IL-5 in bronchoalveolar lavage fluid and lung tissues. In addition, CAE reduced the OVA-specific immunoglobulin (Ig) E, total IgE, IgG1, and IgG2a levels in the serum. In the LPS-induced ALI model, CAE suppressed the LPS-induced lung barrier dysfunction and the release of proinflammatory cytokines. Because allergic airway inflammatory responses are associated with the activation of mast cells, RBL-2H3 cells were used to evaluate the underlying mechanism of CAE effects. In RBL-2H3 cells, CAE down-regulated release of ß-hexosaminidase and histamine by reducing the intracellular calcium influx. In addition, CAE suppressed the expression of proinflammatory cytokines by inhibiting nuclear translocation of nuclear factor-κB. Taken together, our findings suggest that CAE may help in the prevention or treatment of airway inflammatory diseases.

1-Carbomethoxy-ß-Carboline, Derived from Portulaca oleracea L., Ameliorates LPS-Mediated Inflammatory Response Associated with MAPK Signaling and Nuclear Translocation of NF-κB.

Portulaca oleracea is as a medicinal plant known for its neuroprotective, hepatoprotective, antidiabetic, antioxidant, anticancer, antimicrobial, antiulcerogenic, and anti-inflammatory activities. However, the specific active compounds responsible for the individual pharmacological effects of P. oleracea extract (95% EtOH) remain unknown. Here, we hypothesized that alkaloids, the most abundant constituents in P. oleracea extract, are responsible for its anti-inflammatory activity. We investigated the phytochemical substituents (compounds 1-22) using nuclear magnetic resonance (NMR) and electrospray ionization mass spectrometry (ESI-MS) and screened their effects on NO production in lipopolysaccharide (LPS)-induced macrophages. Compound 20, 1-carbomethoxy-ß-carboline, as an alkaloid structure, ameliorated nitric oxide (NO) production, inducible nitric oxide synthase (iNOS), and proinflammatory cytokines associated with the mitogen-activated protein kinase (MAPK) pathways, p38, extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinase (JNK). Subsequently, we observed that compound 20 suppressed nuclear translocation of nuclear factor κB (NF-κB) using immunocytochemistry. Moreover, we recently reported that compound 8, trans-N-feruloyl-3', 7'-dimethoxytyramine, was originally purified from P. oleracea extracts. Our results suggest that 1-carbomethoxy-ß-carboline, the most effective anti-inflammatory agent among alkaloids in the 95% EtOH extract of P. oleracea, was suppressing the MAPK pathway and nuclear translocation of NF-κB. Therefore, P. oleracea extracts and specifically 1-carbomethoxy-ß-carboline may be novel therapeutic candidates for the treatment of inflammatory diseases associated with the activation of MAPKs and NF-κB.

Oleanolic Acid Acetate Exerts Anti-Inflammatory Activity via IKKα/ß Suppression in TLR3-Mediated NF-κB Activation.

Oleanolic acid acetate (OAA), a major triterpenoid compound of Vigna angularis (azuki bean, V. angularis), has been shown to downregulate inflammatory responses in macrophages. Here, we show the molecular basis for the effect of OAA on Toll-like receptor (TLR) downstream signaling. OAA treatment significantly inhibited the secretion of embryonic alkaline phosphatase (SEAP) induced by polyinosinic acid (poly(I), TLR3 ligand) in a dose-dependent manner and without cytotoxicity in THP1-XBlue cells. In addition, OAA downregulated the gene expression of poly(I) induced pro-inflammatory cytokines and chemokines genes such as MCP-1, IL-1ß, IL-8, VCAM-1 and ICAM-1. Furthermore, we found that the inhibition activity of OAA was accompanied by decreased activation of not only nuclear factor-kappa B (NF-κB) signaling but also mitogen-activated protein kinase (MAPK) signaling upon stimulation with the TLR3 agonist. Interestingly, the interaction of OAA with IκB kinase α/ß (IKKα/ß) strongly attenuated the production of certain proteins and inflammatory cytokines in the TLR3 signaling pathway, such as nuclear factor of kappa light polypeptide gene enhancer in B-cells inhibitor, alpha (IkBα), extracellular regulated kinases (ERK), and p38, in an in vitro model. The action of OAA was regulated by TLR3, demonstrating that TLR3 plays a critical role in mediating the physiologically-relevant anti-inflammatory action of OAA and that the interaction with IKKα/ß is modulated through TLR3. These results reveal new insight into the understanding of the regulatory mechanisms of the downstream TLR3 signaling pathway and consequent inflammatory responses that are involved in the development and progression of inflammatory diseases.