Antitumor Effect of Korean Red Ginseng through Blockade of PD-1/PD-L1 Interaction in a Humanized PD-L1 Knock-In MC38 Cancer Mouse Model.

Blocking immune checkpoints, programmed death-1 (PD-1) and its ligand PD-L1, has proven a promising anticancer strategy for enhancing cytotoxic T cell activity. Although we previously demonstrated that ginsenoside Rg3, Rh2, and compound K block the interaction of PD-1 and PD-L1, the antitumor effect through blockade of this interaction by Korean Red Ginseng alone is unknown. Therefore, we determined the effects of Korean Red Ginseng extract (RGE) on the PD-1/PD-L1 interaction and its antitumor effects using a humanized PD-1/PD-L1-expressing colorectal cancer (CRC) mouse model. RGE significantly blocked the interaction between human PD-1 and PD-L1 in a competitive ELISA. The CD8+ T cell-mediated tumor cell killing effect of RGE was evaluated using murine hPD-L1-expressing MC38 cells and tumor-infiltrating hPD-1-expressing CD8+ T cells isolated from hPD-L1 MC38 tumor-bearing hPD-1 mice. RGE also reduced the survival of hPD-L1 MC38 cells in a cell co-culture system using tumor-infiltrating CD8+ T cells as effector cells combined with hPD-L1 MC38 target cells. RGE or Keytruda (positive control) treatment markedly suppressed the growth of hPD-L1 MC38 allograft tumors, increased CD8+ T cell infiltration into tumors, and enhanced the production of Granzyme B. RGE exhibits anticancer effects through the PD-1/PD-L1 blockade, which warrants its further development as an immunotherapy.

Anti-Atopic Effect of Isatidis Folium Water Extract in TNF-α/IFN-γ-Induced HaCaT Cells and DNCB-Induced Atopic Dermatitis Mouse Model.

Isatidis folium or Isatis tinctoria L. is a flowering plant of the Brassicaceae family, commonly known as woad, with an ancient and well-documented history as an indigo dye and medicinal plant. This study aimed to evaluate the anti-atopic dermatitis (AD) effects of Isatidis folium water extract (WIF) using a 2,4-dinitrochlorobenzene (DNCB)-induced AD-like mouse model and to investigate the underlying mechanism using tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ)-activated HaCaT cells. Oral administration of WIF reduced spleen weight, decreased serum IgE and TNF-α levels, reduced epidermal and dermal thickness, and inhibited eosinophil and mast cell recruitment to the dermis compared to DNCB-induced control groups. Furthermore, oral WIF administration suppressed extracellular signal-regulated kinase and p38 mitogen-activated protein kinase protein expression levels, p65 translocation from the cytoplasm to the nucleus, and mRNA expression of TNF-α, IFN-γ, interleukin (IL)-6, and IL-13 in skin lesion tissues. In HaCaT cells, WIF suppressed the production of regulated upon activation, normal T cell expressed and secreted (RANTES), thymus and activation-regulated chemokine (TARC), macrophage-derived chemokine (MDC), MCP-1, and MIP-3a, which are inflammatory cytokines and chemokines related to AD, and inhibited the mRNA expression of RANTES, TARC, and MDC in TNF-α/IFN-γ-stimulated HaCaT cells. Overall, the results revealed that WIF ameliorated AD-like skin inflammation by suppressing proinflammatory cytokine and chemokine production via nuclear factor-κB pathway inhibition, suggesting WIF as a potential candidate for AD treatment.

Anti-Periodontitis Effects of Dendropanax morbiferus H.Lév Leaf Extract on Ligature-Induced Periodontitis in Rats.

Periodontitis is caused by pathogens in the oral cavity. It is a chronic infectious disease that causes symptoms including gingival bleeding and tooth loss resulting from the destruction of periodontal tissues coupled with inflammation. Dendropanax morbiferus H.Lév (DM) is a natural product that exhibits various biological activities with few side effects. In this study, the potential of DM leaf hot-water extracts (DMWE) as a treatment for periodontitis was determined and its anti-oxidant and anti-inflammatory effects were evaluated. Compounds in DMWE were identified by high-performance liquid chromatography (HPLC) and nitric oxide (NO) and prostaglandin E2 (PGE2) production was measured in RAW 264.7 cells. We measured the gingival index and gingival sulcus depth, and micro-CT was performed in vivo using a ligature-induced periodontitis rat model, which is similar to human periodontitis. The DMWE-treated group exhibited a decrease in cytokine concentration and relieved the gingival index and gingival sulcus depth compared with the periodontitis-induced control group. In addition, micro-CT and histological analysis revealed that DMWE exhibited anti-inflammatory effects and improved alveolar bone loss in periodontitis-induced rats. These findings suggest that DMWE has excellent anti-oxidant and anti-inflammatory effects that protect and prevent periodontal tissue damage and tooth loss caused by the inflammatory response.

Indigo Pulverata Levis (Chung-Dae, Persicaria tinctoria) Alleviates Atopic Dermatitis-like Inflammatory Responses In Vivo and In Vitro.

Atopic dermatitis (AD) is a chronic inflammatory skin disease associated with a type 2 T helper cell (Th2) immune response. The IndigoPulverata Levis extract (CHD) is used in traditional Southeast Asian medicine; however, its beneficial effects on AD remain uninvestigated. Therefore, we investigated the therapeutic effects of CHD in 2,4-dinitrochlorobenzene (DNCB)-induced BALB/c mice and tumor necrosis factor (TNF)-α- and interferon gamma (IFN)-γ-stimulated HaCaT cells. We evaluated immune cell infiltration, skin thickness, and the serum IgE and TNF-α levels in DNCB-induced AD mice. Moreover, we measured the expression levels of pro-inflammatory cytokines, mitogen-activated protein kinase (MAPK), and the nuclear factor-kappa B (NF-κB) in the mice dorsal skin. We also studied the effect of CHD on the translocation of NF-κB p65 and inflammatory chemokines in HaCaT cells. Our in vivo results revealed that CHD reduced the dermis and epidermis thicknesses and inhibited immune cell infiltration. Furthermore, it suppressed the proinflammatory cytokine expression and MAPK and NF-κB phosphorylations in the skin tissue and decreased serum IgE and TNF-α levels. In vitro results indicated that CHD downregulated inflammatory chemokines and blocked NF-κB p65 translocation. Thus, we deduced that CHD is a potential drug candidate for AD treatment.

Artemisia anomala Herba Alleviates 2,4-Dinitrochlorobenzene-Induced Atopic Dermatitis-Like Skin Lesions in Mice and the Production of Pro-Inflammatory Mediators in Tumor Necrosis Factor Alpha-/Interferon Gamma-Induced HaCaT Cells.

Artemisia anomala S. Moore is a perennial herbaceous plant classified as Asteraceae of the genus Artemisia. Many species of Artemisia have been used as medicinal materials. Artemisia anomala S. Moore has been widely used in China to treat inflammatory diseases. However, the mechanism of its action on the keratinocyte inflammatory response is poorly understood. Here, we investigated the anti-inflammatory reaction of Artemisia anomala S. Moore ethanol extract (EAA) using human keratinocyte (HaCaT) cells, which involved investigating the nuclear factor kappa B (NF-κB), signal transducer, and activator of transcription-1 (STAT-1), as well as mitogen-activated protein kinase (MAPK) signaling pathways and atopic dermatitis-like skin lesions in mice. We elucidated the anti-inflammatory effects of EAA on tumor necrosis factor-α/interferon-γ (TNF-α/IFN-γ)-treated human keratinocyte cells and 2,4-dinitrochlorobenzene (DNCB)-induced atopic dermatitis (AD)-like mice. The levels of chemokines and cytokines (IL-8, IL-6, TARC, and RANTES) were determined by an enzyme-linked immunosorbent assay. The NF-κB, STAT-1, and MAPK signaling pathways in HaCaT cells were analyzed by western blotting. Thickening of the mice dorsal and ear skin was measured and inflammatory cell infiltration was observed by hematoxylin and eosin staining. Results showed that EAA suppressed IL-8, IL-6, TARC, and RANTES production. EAA inhibited nuclear translocation of NFκB and STAT-1, as well as reduced the levels of phosphorylated ERK MAPKs. EAA improved AD-like skin lesions in DNCB-treated mice. These findings suggest that EAA possesses stronger anti-inflammatory properties and can be useful as a functional food or candidate agent for AD.

Davallia mariesii Moore Improves FcεRI-Mediated Allergic Responses in the Rat Basophilic Leukemia Mast Cell Line RBL-2H3 and Passive Cutaneous Anaphylaxis in Mice.

Davallia mariesii Moore (Drynaria rhizome extract (DRE)) is widely known for its efficacy in treating inflammation, arteriosclerosis, and bone injuries. This study evaluated whether treatment with DRE inhibited FcɛRI-mediated allergic responses in the RBL-2H3 mast cells and investigated the early- and late-phase mechanisms by which DRE exerts its antiallergic effects. IgE anti-DNP/DNP-HSA-sensitized RBL-2H3 mast cells were tested for cytotoxicity to DRE, followed by the assessment of ß-hexosaminidase release. We measured the amounts of inflammatory mediators (e.g., histamine, PGD2, TNF-α, IL-4, and IL-6) and examined the expression of genes involved in arachidonate and FcεRI signaling pathways. In addition, we confirmed the antiallergic effects of DRE on passive cutaneous anaphylaxis (PCA) in mice. DRE inhibited RBL-2H3 mast cell degranulation and production of allergic mediators in them. In early allergic responses, DRE reduced expression of FcεRI signaling-related genes (e.g., Syk, Lyn, and Fyn) and extracellular signal-regulated kinase phosphorylation in mast cells. In late allergic responses, DRE reduced PGD2 release and COX-2 expression and cPLA2 phosphorylation in FcɛRI-mediated mast cells. Lastly, 250-500 mg/kg DRE significantly attenuated the IgE-induced PCA reaction in mice. These findings provide novel information on the molecular mechanisms underlying the antiallergic effects of DRE in FcɛRI-mediated allergic responses.

Ethanol Extract of Sanguisorbae Radix Inhibits Mast Cell Degranulation and Suppresses 2,4-Dinitrochlorobenzene-Induced Atopic Dermatitis-Like Skin Lesions.

Sanguisorbae Radix (SR) is well known as herbal medicine named "Zi-Yu" in Korea, which is the dried roots of Sanguisorba officinalis L. (Rosacease). We investigated the underlying mechanism on the inhibition of atopic dermatitis (AD) of an ethanol extract of SR (ESR) using 2,4-dinitrochlorobenzene- (DNCB-) induced AD mice model. Oral administration of ESR significantly suppressed DNCB-induced AD-like symptoms such as scratching behavior, ear thickness, epidermal thickness, and IgE levels. To investigate the effects of ESR treatment on degranulation of IgE/Ag-activated mouse bone marrow-derived mast cells (BMMCs), we measured the release of ß-hexosaminidase (ß-HEX, degranulation marker). ESR decreased the infiltration of eosinophils and mast cells into the AD skin lesions. Furthermore, ESR significantly inhibited degranulation of IgE/Ag-activated BMMCs. We have demonstrated that ESR decreased AD symptoms in mice and inhibits degranulation of IgE/Ag-activated mast cells. Our study suggests that ESR may serve as a potential therapeutic candidate for the treatment of AD symptoms.

Inhibitory Effect of Loranthus parasiticus on IgE-Mediated Allergic Responses in RBL-2H3 Cells.

The mistletoe Loranthus parasiticus has been used as a compound for traditional medicine in Northeast Asia for a long time and is known to possess neuroprotective action. Nonetheless, the effect of Loranthus parasiticus on allergic responses remains unknown. In the present study, we evaluated whether the water extract of Loranthus parasiticus (LPE) could inhibit IgE-mediated allergic responses in RBL-2H3 cells. LPE inhibited the release of ß-hexosaminidase (IC50, 184.5 µg/mL) and the formation of tumor necrosis factor-α (IC50, 84.27 µg/mL), interleukin-4 (IC50, 93.43 µg/mL), prostaglandin E2 (IC50, 84.10 µg/mL), prostaglandin D2, and leukotriene C4 (IC50, 43.27 µg/mL) in a concentration-dependent manner. Moreover, LPE inhibited phosphorylation of Syk, PLCγ1/2, PKCδ, ERK, JNK, p38, and Akt. In the late phase, LPE decreased 5-lipoxygenase phosphorylation and COX-2 expression but not cPLA2 phosphorylation. Additionally, LPE included total phenolic compounds (10.72 mg/g dry weight) and total flavonoids (56.20 mg/g dry weight). These results suggest that the phenolic compounds or flavonoids contained in LPE may be associated with antiallergic activity. The phenolic compounds and flavonoids in LPE are antiallergic phytochemicals capable of inhibiting the activation of the FcεRI signaling cascade in mast cells. Such effects may provide further information for the development of a phytomedicine for allergic diseases.

Anti-inflammatory effects of Sanguisorbae Radix water extract on the suppression of mast cell degranulation and STAT-1/Jak-2 activation in BMMCs and HaCaT keratinocytes.

BACKGROUND: Sanguisorbae Radix (SR) is a well-known herbal medicine used to treat inflammatory disease and skin burns in Asia. In addition, it is used to treat many types of allergic skin diseases, including urticaria, eczema, and allergic dermatitis. SR has been reported to exhibit anti-wrinkle, anti-oxidant, and anti-contact dermatitis bioactivities. METHODS: In this study, we investigated the mechanism underlying the anti-inflammatory effects of SR water extract (WSR) using human keratinocyte (HaCaT) cells and BALB/c mouse bone marrow-derived mast cells (BMMCs). Viability assays were used to evaluate non-cytotoxic concentrations of WSR in both BMMCs and HaCaT cells. To investigate the effect of WSR treatment on the degranulation of IgE/Ag-activated BMMCs, we measured the release of ß-hexosaminidase (ß-HEX). We determined the production of pro-inflammatory chemokines including thymus and activation regulated chemokine (TARC; CCL17), regulated on activation, normal T-cell expressed and secreted (RANTES; CCL5), macrophage-derived chemokine (MDC; CCL22), and interleukin 8 (IL-8; CXCL8) in stimulated human keratinocytes. The ability of WSR to reduce the expression of pro-inflammatory marker proteins was evaluated by Western blotting in HaCaT cells stimulated with tumor necrosis factor (TNF)-α/interferon (IFN)-γ. RESULT: WSR inhibited IgE/Ag-activated mast cell degranulation in BMMCs. Treatment with various concentrations of WSR decreased ß-HEX release in a dose-dependent manner with an IC50 of 27.5 µg/mL. In keratinocytes, WSR suppressed TNF-α/IFN-γ-induced chemokine production and pro-inflammatory molecules via a blockade STAT-1, Jak-2, p38, and JNK activation. CONCLUSIONS: This results demonstrate that WSR inhibits degranulation of IgE/Ag-activated mast cells and inhibits the production of pro-inflammatory chemokines by suppressing the phosphorylation of p38 and JNK in HaCaT cells.

Inhibitory Effects of Viscum coloratum Extract on IgE/Antigen-Activated Mast Cells and Mast Cell-Derived Inflammatory Mediator-Activated Chondrocytes.

The accumulation and infiltration of mast cells are found in osteoarthritic lesions in humans and rodents. Nonetheless, the roles of mast cells in osteoarthritis are almost unknown. Although Viscum coloratum has various beneficial actions, its effect on allergic and osteoarthritic responses is unknown. In this study, we established an in vitro model of mast cell-mediated osteoarthritis and investigated the effect of the ethanol extract of Viscum coloratum (VEE) on IgE/antigen (IgE/Ag)-activated mast cells and mast cell-derived inflammatory mediator (MDIM)-stimulated chondrocytes. The anti-allergic effect of VEE was evaluated by degranulation, inflammatory mediators, and the FcεRI signaling cascade in IgE/Ag-activated RBL-2H3 cells. The anti-osteoarthritic action of VEE was evaluated by cell migration, and the expression, secretion, and activity of MMPs in MDIM-stimulated SW1353 cells. VEE significantly inhibited degranulation (IC50: 93.04 µg/mL), the production of IL-4 (IC50: 73.28 µg/mL), TNF-α (IC50: 50.59 µg/mL), PGD2 and LTC4, and activation of the FcεRI signaling cascade in IgE/Ag-activated RBL-2H3 cells. Moreover, VEE not only reduced cell migration but also inhibited the expression, secretion, and/or activity of MMP-1, MMP-3, or MMP-13 in MDIM-stimulated SW1353 cells. In conclusion, VEE possesses both anti-allergic and anti-osteoarthritic properties. Therefore, VEE could possibly be considered a new herbal drug for anti-allergic and anti-osteoarthritic therapy. Moreover, the in vitro model may be useful for the development of anti-osteoarthritic drugs.

Liquid Chromatography/Tandem Mass Spectrometry Analysis of Sophora flavescens Aiton and Protective Effects against Alcohol-Induced Liver Injury and Oxidative Stress in Mice.

In this study, we investigated the hepatoprotective effects of an ethanol extract of Sophora flavescens Aiton (ESF) on an alcohol-induced liver disease mouse model. Alcoholic liver disease (ALD) was caused by the administration of ethanol to male C57/BL6 mice who were given a Lieber-DeCarli liquid diet, including ethanol. The alcoholic fatty liver disease mice were orally administered ESF (100 and 200 mg/kg bw/day) or silymarin (50 mg/kg bw/day), which served as a positive control every day for 16 days. The findings suggest that ESF enhances hepatoprotective benefits by significantly decreasing serum levels of aspartate transaminase (AST) and alanine transaminase (ALT), markers for liver injury. Furthermore, ESF alleviated the accumulation of triglyceride (TG) and total cholesterol (TC), increased serum levels of superoxide dismutase (SOD) and glutathione (GSH), and improved serum alcohol dehydrogenase (ADH) activity in the alcoholic fatty liver disease mice model. Cells and organisms rely on the Kelch-like ECH-associated protein 1- Nuclear factor erythroid 2-related factor 2 (Keap1-Nrf2) system as a critical defensive mechanism in response to oxidative stress. Therefore, Nrf2 plays an important role in ALD antioxidant responses, and its level is decreased by increased reactive oxidation stress (ROS) in the liver. ESF increased Nrf2, which was decreased in ethanol-damaged livers. Additionally, four polyphenol compounds were identified through a qualitative analysis of the ESF using LC-MS/MS. This study confirmed ESF's antioxidative and hangover-elimination effects and suggested the possibility of using Sophora flavescens Aiton (SF) to treat ALD.

Ziziphus jujuba Miller Ethanol Extract Restores Disrupted Intestinal Barrier Function via Tight Junction Recovery and Reduces Inflammation.

Inflammatory bowel disease (IBD) is a chronic inflammatory condition caused by the disruption of the intestinal barrier. The intestinal barrier is maintained by tight junctions (TJs), which sustain intestinal homeostasis and prevent pathogens from entering the microbiome and mucosal tissues. Ziziphus jujuba Miller (Z. jujuba) is a natural substance that has been used in traditional medicine as a therapy for a variety of diseases. However, in IBD, the efficacy of Z. jujuba is unknown. Therefore, we evaluated ZJB in Caco2 cells and a dextran sodium sulfate (DSS)-induced mouse model to demonstrate its efficacy in IBD. Z. jujuba extracts were prepared using 70% ethanol and were named ZJB. ZJB was found to be non-cytotoxic and to have excellent antioxidant effects. We confirmed its anti-inflammatory properties via the down-regulation of inflammatory factors, including inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2). To evaluate the effects of ZJB on intestinal barrier function and TJ improvement, the trans-epithelial electrical resistance (TEER) and fluorescein isothiocyanate-dextran 4 kDa (FITC-Dextran 4) permeability were assessed. The TEER value increased by 61.389% and permeability decreased by 27.348% in the 200 µg/mL ZJB group compared with the 50 ng/mL IL-6 group after 24 h. Additionally, ZJB alleviated body weight loss, reduced the disease activity index (DAI) score, and induced colon shortening in 5% DSS-induced mice; inflammatory cytokines, tumor necrosis factor (TNF)-α, and interleukin (IL)-6 were down-regulated in the serum. TJ proteins, such as Zonula occludens (ZO)-1 and occludin, were up-regulated by ZJB in an impaired Caco2 mouse model. Additionally, according to the liquid chromatography results, in tandem with mass spectrometry (LC-MS/MS) analysis, seven active ingredients were detected in ZJB. In conclusion, ZJB down-regulated inflammatory factors, protected intestinal barrier function, and increased TJ proteins. It is thus a safe, natural substance with the potential to be used as a therapeutic agent in IBD treatment.

Tanshinone IIA improves endoplasmic reticulum stress-induced insulin resistance through AMP-activated protein kinase.

The aim of the present study was to determine the effect of Tanshinone IIA (Tan IIA) on endoplasmic reticulum (ER) stress-induced insulin resistance in L6 myotubes and db/db mice. ER stress markers, RNA-activated protein kinase-like ER resident kinase (PERK), JNK, and AMPK activity were determined in tunicamycin-treated L6 myotubes. Insulin resistance was monitored using glucose uptake assays in vitro and blood glucose levels in vivo. Tan IIA clearly suppressed the phosphorylations of PERK and JNK and potentiated insulin-mediated Akt phosphorylation as well as glucose uptake via AMPK activation under ER stress. Furthermore, these effects are completely abrogated by siRNA-mediated knockdown of AMPK or LKB1. In addition, Tan IIA reduced blood glucose levels and body weights in db/db mice without altering food intake. These findings suggest that Tan IIA enhances insulin sensitivity and improves glucose metabolic disorders by increasing AMPK activity and attenuating ER stress-induced insulin resistance.

Systemic and molecular analysis dissect the red ginseng induction of apoptosis and autophagy in HCC as mediated with AMPK.

Background: Hepatocellular carcinoma (HCC) has a high incidence and is one of the highest mortality cancers when advanced stage is proceeded. However, Anti-cancer drugs available for treatment are limited and new anti-cancer drugs and new ways to treat them are minimal. We examined that the effects and possibility of Red Ginseng (RG, Panax ginseng Meyer) as new anti-cancer drug on HCC by combining network pharmacology and molecular biology. Materials and Methods: Network pharmacological analysis was employed to investigate the systems-level mechanism of RG focusing on HCC. Cytotoxicity of RG was determined by MTT analysis, which were also stained by annexin V/PI staining for apoptosis and acridine orange for autophagy. For the analyze mechanism of RG, we extracted protein and subjected to immunoblotting for apoptosis or autophagy related proteins. Results: We constructed compound-target network of RG and identified potential pathways related to HCC. RG inhibited growth of HCC through acceleration of cytotoxicity and reduction of wound healing ability of HCC. RG also increased apoptosis and autophagy through AMPK induction. In addition, its ingredients, 20S-PPD (protopanaxadiol) and 20S-PPT (protopanaxatriol), also induced AMPK mediated apoptosis and autophagy. Conclusion: RG effectively inhibited growth of HCC cells inducing apoptosis and autophagy via ATG/AMPK in HCC cells. Overall, our study suggests possibility as new anti-cancer drug on HCC by proof for the mechanism of the anti-cancer action of RG.

Natural vanadium-containing Jeju groundwater inhibits immunoglobulin E-mediated anaphylactic reaction and suppresses eicosanoid generation and degranulation in bone marrow derived-mast cells.

The high-affinity receptor for immunoglobulin E (IgE) (FcεRI)-mediated activation of mast cells plays an important role in various allergic diseases. To assess the anti-allergic activity of natural vanadium-containing Jeju groundwater (JW), an in vivo passive cutaneous anaphylaxis (PCA) animal model and in vitro mouse bone marrow-derived mast cells (BMMCs) was used. JW inhibited cyclooxygenase-2 (COX-2)-dependent prostaglandin D(2) (PGD(2)) generation in a dose-dependent manner, with a concomitant reduction of COX-2 protein expression in IgE-induced BMMCs. In addition, JW inhibited 5-lipoxygenase (5-LOX)-dependent generation of leukotriene C(4) (LTC(4)) as well as degranulation in a dose-dependent manner. These results demonstrate that JW has dual COX-2/5-LOX inhibitory activity. In addition, vanadium pentoxide (V(2)O(5)), which is the major vanadium component of JW, also inhibited PGD(2) and LTC(4) generation as well as degranulation in IgE-induced BMMCs. Furthermore, oral administration of JW dose-dependently inhibited mast cell-dependent passive anaphylactic reaction in IgE-sensitized mice. Taken together, these results suggest that JW may be useful in regulating mast cell-mediated allergic response through the suppression of eicosanoid generation and degranulation in mast cells.

Augmented Antitumor Effect of Unripe Rubus coreanus Miquel Combined with Oxaliplatin in a Humanized PD-1/PD-L1 Knock-In Colorectal Cancer Mouse Model.

Immune checkpoint inhibitors (ICIs) have been shown to be extraordinarily effective in patients with colorectal cancer (CRC). However, the current ICIs still have adverse effects and limited efficacy of ICI monotherapy. We used a natural product to overcome the vulnerability of ICIs and tried a combination therapy with oxaliplatin to enhance the programmed death-1/programmed death-ligand 1 (PD-1/PD-L1) blockade anticancer effect. In the present study, we evaluated the T cell-mediated antitumor immunity with Unripe Rubus coreanus Miquel extract (RCE), which exerts anticancer properties via PD-1/PD-L1 blockade, combined with oxaliplatin in a co-culture cell model and allograft tumor humanized PD-1 mice. We found that RCE plus oxaliplatin apparently activates hPD-1 tumor-infiltrating CD8+ T cells, resulting in elevations of released interleukin-2 (IL-2) and granzyme B (GrB), and kills hPD-L1 MC38 CRC cells. RCE plus oxaliplatin considerably reduced tumor growth in humanized PD-1/PD-L1-expressing mouse MC38 CRC allograft. Moreover, RCE plus oxaliplatin remarkably increased the infiltration of CD8+ T cells in tumor tissues, as well as increasingly produced GrB of tumor-infiltrating CD8+ T cells in the tumor microenvironment. Our study delineated combination therapy with RCE as a PD-1/PD-L1 blockade and oxaliplatin to improve the response to immune checkpoint blockade therapy in conjunction with standard chemotherapy regimens in CRC.

Maclurin Exhibits Antioxidant and Anti-Tyrosinase Activities, Suppressing Melanogenesis.

Maclurin is rich in some edible fruits such as Morus alba (white mulberry) and Garcinia mangostana. Although maclurin showed anti-cancer and antioxidant effects, its roles in ultraviolet (UV)-induced melanogenesis have not been studied. Here, we investigated the effects of maclurin in melanogenesis using skin cells and a three-dimensional human skin model. When the cytotoxicity of maclurin was examined in B16F10 cells, no cytotoxicity was found up to 20 µM. Maclurin suppressed UVB-mediated tyrosinase activation and melanin accumulation in B16F10 cells without changes in mRNA levels of melanogenesis-related genes including tyrosinase, TRP1, TRP2, CREB, and MITF. Moreover, maclurin reduced melanin contents in melan-a cells, a cell line for normal melanocytes. When applied to a human skin model consisting of the epidermis and melanocytes, maclurin significantly reduced UVB-induced melanin accumulation (~47%) in a concentration-dependent manner based on microscopic observation and Fontana-Masson staining. Protein-ligand docking simulation followed by binding residue analysis showed that maclurin may bind to inactivate tyrosinase by forming multiple hydrogen bonds and hydrophobic and aromatic interactions with the residues of tyrosinase. Together, our study suggests that maclurin may be applied as an anti-melanogenic agent.

Inhibitory effect of Isatis tinctoria L. water extract on DNCB-induced atopic dermatitis in BALB/c mice and HaCaT cells.

BACKGROUND: Isatis tinctoria L (PLG) is a medicinal herb from the roots of Isatis indigotica Fort (Family Cruciferae). Previous studies have shown that PLG has anti-inflammatory and therapeutic effects against conditions such as acute and chronic hepatitis, various respiratory inflammations, and cancer. The purpose of this study was to define the pharmacological effects of PLG on inflammatory reactions and skin hyperkeratosis, which are the main symptoms of atopic dermatitis (AD), in vivo and in vitro. METHODS: For the AD in vivo experiment, 2,4-dinitrochlorobenzene (DNCB) induction and oral administration of PLG were performed on male BALB/c mice for four weeks. For in vitro experiments, keratinocytes were activated using TNF-α/IFN-γ in cultured human keratinocyte (HaCaT) cells. PLG inhibited inflammatory chemokine production and blocked the nuclear translocation of NF-κB p65 in activated keratinocytes. RESULTS: As a result of oral administration of PLG, dermis and epidermis thickening, as well as eosinophil and mast cell infiltration, were attenuated in AD skin lesions. In addition, the levels of immunoglobulin E (IgE), pro-inflammatory cytokines, and the MAPK/NF-κB signaling pathway were decreased in serum and dorsal skin tissues. Furthermore, PLG inhibited inflammatory chemokine production and blocked the nuclear translocation of NF-κB p65 in activated keratinocytes. In addition, epigoitrin and adenosine, the standard compounds of PLG, were identified as candidate AD compounds. CONCLUSIONS: These results indicate that PLG is a potent therapeutic agent for attenuating symptoms of AD.

Deoxypodophyllotoxin inhibits the expression of intercellular adhesion molecule-1 induced by tumor necrosis factor-alpha in murine lung epithelial cells.

Intercellular adhesion molecule-1 (ICAM-1) is associated with processes of inflammation. We investigated the effects of deoxypodophyllotoxin (DPT) on tumor necrosis factor-alpha (TNF-alpha) induced ICAM-1 expression in the mouse lung epithelial cell line, LA4. DPT (5 to 20 nM) inhibited TNF-alpha-induced ICAM-1 expression through nuclear factor-kappa B (NF-kappaB) in a dose-dependent manner and repressed ICAM-1 promoter activity. NF-kappaB reporter gene activity and DNA binding activity were also strongly inhibited. In addition, DPT inhibited degradation by the TNF-alpha induced inhibitory kappaB-alpha (IkappaB-alpha) in a concentration-dependent manner. Taken together with our previous results suggest DPT might provide a basis for novel anti-inflammatory drug development.

Author Correction: Sirt1 negatively regulates FcεRI-mediated mast cell activation through AMPK- and PTP1B-dependent processes.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.