Anti-inflammatory effects of neuregulin-1 in HaCaT keratinocytes and atopic dermatitis-like mice stimulated with Der p 38.

Neuregulin (NRG)-1 plays fundamental roles in several organ systems after binding to its receptors, ErbB2 and ErbB4. This study examines the role of NRG-1 in atopic dermatitis (AD), a chronic skin disease that causes dryness, pruritus, and inflammation. In mice administered Der p 38, the skin presents AD-like symptoms including filaggrin downregulation and infiltration of neutrophils and eosinophils. Noticeably, there is an increased expression of NRG-1, ErbB2, and ErbB4 in the skin. Upregulation of these proteins is significantly correlated to the clinical skin severity score. In human keratinocyte HaCaT cells, exposure to Der p 38 decreased filaggrin expression, and NRG-1 alone had no effect on the expression. However, co-treatment of Der p 38 with NRG-1 enhanced the filaggrin expression decreased by Der p 38. Pre-treatment with AG879 (an ErbB2 inhibitor) or ErbB4 siRNA blocked the recovery of filaggrin expression in the cells after co-treatment with Der p 38 and NRG-1. Der p 38 treatment enhanced the secretion of interleukin-6 (IL-6), IL-8, and monocyte chemoattractant protein-1 (MCP-1). Co-treatment of Der p 38 with NRG-1 lowered the cytokine secretion increased by Der p 38, although NRG-1 alone was not effective on cytokine alteration. Neutrophil apoptosis was not altered by NRG-1 or supernatants of cells treated with NRG-1, but the cell supernatants co-treated with Der p 38 and NRG-1 blocked the anti-apoptotic effects of Der p 38-treated supernatants on neutrophils, which was involved in the activation of caspase 9 and caspase 3. Taken together, we determined that NRG-1 has anti-inflammatory effects in AD triggered by Der p 38. These results will pave the way to understanding the functions of NRG-1 and in the future development of AD treatment.

Der p 38 Is a Bidirectional Regulator of Eosinophils and Neutrophils in Allergy.

The house dust mite is the most common cause of allergic diseases, and TLR4 acts as an overarching receptor for allergic responses. This study aimed to identify novel allergen binding to TLR4 in house dust mites and unveil its unique role in allergic responses. Der p 38 was purified and characterized by liquid chromatography tandem mass spectrometry-based peptide mapping. Biolayer interferometry and structure modeling unveiled TLR4-binding activity and the structure of recombinant Der p 38. The allergenicity of Der p 38 was confirmed by a skin prick test, and basophil activation and dot blot assays. The skin prick test identified 24 out of 45 allergic subjects (53.3%) as Der p 38+ subjects. Der p 38-augmented CD203c expression was noted in the basophils of Der p 38+ allergic subjects. In animal experiments with wild-type and TLR4 knockout BALB/c mice, Der p 38 administration induced the infiltration of neutrophils as well as eosinophils and exhibited clinical features similar to asthma via TLR4 activation. Persistent Der p 38 administration induced severe neutrophil inflammation. Der p 38 directly suppressed the apoptosis of allergic neutrophils and eosinophils, and enhanced cytokine production in human bronchial epithelial cells, inhibiting neutrophil apoptosis. The mechanisms involved TLR4, LYN, PI3K, AKT, ERK, and NF-κB. These findings may contribute to a deep understanding of Der p 38 as a bridge allergen between eosinophilic and neutrophilic inflammation in the pathogenic mechanisms of allergy.

The ameliorative effects of capsidiol isolated from elicited Capsicum annuum on mouse splenocyte immune responses and neuroinflammation.

Capsidiol, is an anti-fungal phytoalexin produced by plants of Solanaceae. Capsidiol was examined in cultures of primary splenocytes (SPLCs) isolated from healthy C57BL/6 mice and from those with induced experimental autoimmune encephalomyelitis (EAE) as a mouse model for autoimmune neurodegenerative multiple sclerosis (MS). We also examined the impact of capsidiol in IFN-γ-stimulated mouse BV2 microglial cells. Capsidiol resulted in a significant reduction in the anti-CD3/CD28 (αCD3/CD28)-induced IFN-γ+ CD4+ (Th1) and IFN-γ+ CD8+ (Tc1) populations as well as in the production of cytokines (IFN-γ, IL-17A, IL-6, IL-2, TNF-α, and IP-10). Specifically, the CD4+ and CD8+ populations (T-bet+ IFN-γ- , T-bet+ IFN-γ+ , and T-bet- IFN-γ+ ) and cytokine production mediated by Th1/Tc1 polarization were diminished by 25 µM capsidiol. MOG35-55 restimulation of SPLCs from EAE mice resulted in an increase in antigen-specific T cells, including Th1, IL-17A+ CD4+ (Th17), and IL-17A+ CD8+ (Tc17) populations. By contrast, capsidiol resulted in a decrease in the proportions of Th17 and Tc17 cells; MOG35-55 -specific cytokine production was also diminished by capsidiol. Capsidiol treatment resulted in diminished levels of IFN-γ-induced nitric oxide and IL-6; expression of iNOS and COX-2 were suppressed by 50 µM capsidiol in IFN-γ-stimulated BV2 cells. This is the first report of capsidiol-mediated immunomodulatory and antineuroinflammatory activities that may serve to prevent neurodegeneration.

Der f 38 Is a Novel TLR4-Binding Allergen Related to Allergy Pathogenesis from Dermatophagoides farinae.

It is difficult to treat allergic diseases including asthma completely because its pathogenesis remains unclear. House dust mite (HDM) is a critical allergen and Toll-like receptor (TLR) 4 is a member of the toll-like receptor family, which plays an important role in allergic diseases. The purpose of this study was to characterize a novel allergen, Der f 38 binding to TLR4, and unveil its role as an inducer of allergy. Der f 38 expression was detected in the body and feces of Dermatophagoides farinae (DF). Electron microscopy revealed that it was located in the granule layer, the epithelium layer, and microvilli of the posterior midgut. The skin prick test showed that 60% of allergic subjects were Der f 38-positive. Der f 38 enhanced surface 203c expression in basophils of Der f 38-positive allergic subjects. By analysis of the model structure of Der p 38, the expected epitope sites are exposed on the exterior side. In animal experiments, Der f 38 triggered an infiltration of inflammatory cells. Intranasal (IN) administration of Der f 38 increased neutrophils in the lung. Intraperitoneal (IP) and IN injections of Der f 38 induced both eosinophils and neutrophils. Increased total IgE level and histopathological features were found in BALB/c mice treated with Der f 38 by IP and IN injections. TLR4 knockout (KO) BALB/c mice exhibited less inflammation and IgE level in the sera compared to wild type (WT) mice. Der f 38 directly binds to TLR4 using biolayer interferometry. Der f 38 suppressed the apoptosis of neutrophils and eosinophils by downregulating proteins in the proapoptotic pathway including caspase 9, caspase 3, and BAX and upregulating proteins in the anti-apoptotic pathway including BCL-2 and MCL-1. These findings might shed light on the pathogenic mechanisms of allergy to HDM.

Oat Extract Avenanthramide-C Reverses Hippocampal Long-Term Potentiation Decline in Tg2576 Mice.

Memory deterioration in Alzheimer's disease (AD) is thought to be underpinned by aberrant amyloid ß (Aß) accumulation, which contributes to synaptic plasticity impairment. Avenanthramide-C (Avn-C), a polyphenol compound found predominantly in oats, has a range of biological properties. Herein, we performed methanolic extraction of the Avns-rich fraction (Fr. 2) from germinated oats using column chromatography, and examined the effects of Avn-C on synaptic correlates of memory in a mouse model of AD. Avn-C was identified in Fr. 2 based on 1H-NMR analysis. Electrophysiological recordings were performed to examine the effects of Avn-C on the hippocampal long-term potentiation (LTP) in a Tg2576 mouse model of AD. Avn-C from germinated oats restored impaired LTP in Tg2576 mouse hippocampal slices. Furthermore, Avn-C-facilitated LTP was associated with changes in the protein levels of phospho-glycogen synthase kinase-3ß (p-GSK3ß-S9) and cleaved caspase 3, which are involved in Aß-induced synaptic impairment. Our findings suggest that the Avn-C extract from germinated oats may be beneficial for AD-related synaptic plasticity impairment and memory decline.

Suppressive effects of S100A8 and S100A9 on neutrophil apoptosis by cytokine release of human bronchial epithelial cells in asthma.

S100A8 and S100A9 are important proteins in the pathogenesis of allergy. Asthma is an allergic lung disease, characterized by bronchial inflammation due to leukocytes, bronchoconstriction, and allergen-specific IgE. In this study, we examined the role of S100A8 and S100A9 in the interaction of cytokine release from bronchial epithelial cells, with constitutive apoptosis of neutrophils. S100A8 and S100A9 induce increased secretion of neutrophil survival cytokines such as MCP-1, IL-6 and IL-8. This secretion is suppressed by TLR4 inhibitor), LY294002, AKT inhibitor, PD98059, SB202190, SP600125, and BAY-11-7085. S100A8 and S100A9 also induce the phosphorylation of AKT, ERK, p38 MAPK and JNK, and activation of NF-κB, which were blocked after exposure to TLR4i, LY294002, AKTi, PD98059, SB202190 or SP600125. Furthermore, supernatants collected from bronchial epithelial cells after S100A8 and S100A9 stimulation suppressed the apoptosis of normal and asthmatic neutrophils. These inhibitory mechanisms are involved in suppression of caspase 9 and caspase 3 activation, and BAX expression. The degradation of MCL-1 and BCL-2 was also blocked by S100A8 and S100A9 stimulation. Essentially, neutrophil apoptosis was blocked by co-culture of normal and asthmatic neutrophils with BEAS-2B cells in the presence of S100A8 and S100A9. These findings will enable elucidation of asthma pathogenesis.

Neuroinflammation and B-Cell Phenotypes in Cervical and Lumbosacral Regions of the Spinal Cord in Experimental Autoimmune Encephalomyelitis in the Absence of Pertussis Toxin.

OBJECTIVES: The active experimental autoimmune encephalomyelitis (EAE) model is often initiated using myelin oligodendrocyte glycoprotein (MOG) immunization followed by pertussis toxin (PTX) to study multiple sclerosis. However, PTX inactivates G protein-coupled receptors, and with increasing knowledge of the role that various G protein-coupled receptors play in immune homeostasis, it is valuable to establish neuroimmune endpoints for active EAE without PTX. METHODS: Female C57BL/6 mice were immunized with MOG35-55 peptide in Complete Freund's Adjuvant and neuroinflammation, including central nervous system B-cell infiltration, was compared to saline-injected mice. Since it was anticipated that disease onset would be slower and less robust than EAE in the presence of PTX, both cervical and lumbosacral sections of the spinal cord were evaluated. RESULTS: Immunohistochemical analysis showed that EAE without PTX induced immune infiltration, CCL2 and VCAM-1 upregulation. Demyelination in the cervical region correlated with the infiltration of CD19+ B cells in the cervical region. There was upregulation of IgG, CD38, and PDL1 on B cells in cervical and lumbosacral regions of the spinal cord in EAE without PTX. Interestingly, IgG was expressed predominantly by CD19- cells. CONCLUSIONS: These data demonstrate that many neuroimmune endpoints are induced in EAE without PTX and although clinical disease is mild, this can be used as an autoimmune model when PTX inactivation of G protein-coupled receptors is not desired.

Persistent organic pollutants (POPs) increase rage signaling to promote downstream cardiovascular remodeling.

Exposure to environmental contaminants and consumption of a high, saturated fatty diet has been demonstrated to promote precursors for metabolic syndrome (hyperglycemia, hyperinsulinemia, and hypertriglyceridemia). The purpose of this study was to determine if exposure to the most prevalent environmental persistent organic pollutants (POPs) would act as causative agents to promote metabolic syndrome independent of dietary intake. We hypothesized that POPs will activate the advanced glycated end-product (AGE)-and receptor for AGE (RAGE) signaling cascade to promote downstream signaling modulators of cardiovascular remodeling and oxidative stress in the heart. At 5-weeks of age nondiabetic (WT) and diabetic (ob/ob) mice were exposed POPs mixtures by oral gavage twice a week for 6-weeks. At the end of 6-weeks, animals were sacrificed and the hearts were taken for biochemical analysis. Increased activation of the AGE-RAGE signaling cascade via POPs exposure resulted in elevated levels of fibroblast differentiation (α-smooth muscle actin) and RAGE expression indicated maladaptive cardiac remodeling. Conversely, the observed decreased superoxide dismutase-1 and -2 (SOD-1 and SOD-2) expression may exacerbate the adverse changes occurring as a result of POPs treatment to reduce innate cardioprotective mechanisms. In comparison, ventricular collagen levels were decreased in mice exposed to POPs. In conclusion, exposure to organic environmental pollutants may intensify oxidative and inflammatory stressors to overwhelm protective mechanisms allowing for adverse cardiac remodeling.

A Fuzzy-Innovation-Based Adaptive Kalman Filterfor Enhanced Vehicle Positioning in DenseUrban Environments.

In this paper, a fuzzy-innovation based adaptive extended Kalman filter (FI-AKF)is proposed to improve the performance of the GNSS/INS fusion system, which is degradeddue to satellite signal cutoff and attenuation and inaccurate modeling in dense urbanenvironments. The information used for sensor fusion is obtained from real-time kinematic (RTK),micro-electro-mechanical system based inertial measumrement unit (MEMS-IMU), and on-boarddiagnostics (OBD). The fuzzy logic system is proposed to adaptively update the measurementcovariance matrix of the RTK according to the position dilution of precision (PDOP), the numberof receivable satellites, and the innovation of the extended Kalman filter (EKF). In addition, thedriving state of the vehicle is defined as stop, straight run, left/right turn, and the like. To reduce theheading estimation error of the Kalman filter, the estimated heading is corrected according to thedriving state. Also, the measurement covariance matrices of IMU and OBD are applied adaptivelyconsidering the characteristics of each sensor according to the driving state. In order to analyze theperformance of the proposed FI-AKF positioning system in a dense urban environment, a computersimulation is performed. The proposed FI-AKF is compared to the performance of the existingextended Kalman filter and the innovation-based adaptive extended Kalman filter. In addition, weconduct a performance comparison experiment with a commercial positioning system in the field test.Through each experiment, it is confirmed that the proposed FI-AKF system has higher positioningperformance than the comparison positioning systems in a dense urban environment.

Simultaneous Determination and Pharmacokinetic Characterization of Glycyrrhizin, Isoliquiritigenin, Liquiritigenin, and Liquiritin in Rat Plasma Following Oral Administration of Glycyrrhizae Radix Extract.

Glycyrrhizae Radix is widely used as herbal medicine and is effective against inflammation, various cancers, and digestive disorders. We aimed to develop a sensitive and simultaneous analytical method for detecting glycyrrhizin, isoliquiritigenin, liquiritigenin, and liquiritin, the four marker components of Glycyrrhizae Radix extract (GRE), in rat plasma using liquid chromatography-tandem mass spectrometry and to apply this analytical method to pharmacokinetic studies. Retention times for glycyrrhizin, isoliquiritigenin, liquiritigenin, and liquiritin were 7.8 min, 4.1 min, 3.1 min, and 2.0 min, respectively, suggesting that the four analytes were well separated without any interfering peaks around the peak elution time. The lower limit of quantitation was 2 ng/mL for glycyrrhizin and 0.2 ng/mL for isoliquiritigenin, liquiritigenin, and liquiritin; the inter- and intra-day accuracy, precision, and stability were less than 15%. Plasma concentrations of glycyrrhizin, isoliquiritigenin, liquiritigenin, and liquiritin were quantified for 24 h after a single oral administration of 1 g/kg GRE to four rats. Among the four components, plasma concentration of glycyrrhizin was the highest and exhibited a long half-life (23.1 ± 15.5 h). Interestingly, plasma concentrations of isoliquiritigenin and liquiritigenin were restored to the initial concentration at 4-10 h after the GRE administration, as evidenced by liquiritin biotransformation into isoliquiritigenin and liquiritigenin, catalyzed by fecal lysate and gut wall enzymes. In conclusion, our analytical method developed for detecting glycyrrhizin, isoliquiritigenin, liquiritigenin, and liquiritin could be successfully applied to investigate their pharmacokinetic properties in rats and would be useful for conducting further studies on the efficacy, toxicity, and biopharmaceutics of GREs and their marker components.

Isolation, Synthesis, and Antisepsis Effects of a C-Methylcoumarinochromone Isolated from Abronia nana Cell Culture.

Only a few isoflavones have been isolated from plants of the genus Abronia. The biological properties of compounds isolated from Abronia species have not been well established, and their antisepsis effects have not been reported yet. In the present study, a new C-methylcoumarinochromone, was isolated from Abronia nana suspension cultures. Its structure was deduced as 9,11-dihydroxy-10-methylcoumarinochromone (boeravinone Y, 1) by spectroscopic data analysis and verified by chemical synthesis. The potential inhibitory effects of 1 against high mobility group box 1 (HMGB1)-mediated septic responses were investigated. Results showed that 1 effectively inhibited lipopolysaccharide-induced release of HMGB1 and suppressed HMGB1-mediated septic responses, in terms of reduction of hyperpermeability, leukocyte adhesion and migration, and cell adhesion molecule expression. In addition, 1 increased the phagocytic activity of macrophages and exhibited bacterial clearance effects in the peritoneal fluid and blood of mice with cecal ligation and puncture-induced sepsis. Collectively, these results suggested that 1 might have potential therapeutic activity against various severe vascular inflammatory diseases via inhibition of the HMGB1 signaling pathway.

Oleuropein isolated from Fraxinus rhynchophylla inhibits glutamate-induced neuronal cell death by attenuating mitochondrial dysfunction.

Glutamate-induced neurotoxicity is related to excessive oxidative stress accumulation and results in the increase of neuronal cell death. In addition, glutamate has been reported to lead to neurodegenerative diseases, including Parkinson's and Alzheimer's diseases.It is well known that Fraxinus rhynchophylla contains a significant level of oleuropein (Ole), which exerts various pharmacological effects. However, the mechanism of neuroprotective effects of Ole is still poorly defined. In this study, we aimed to investigate whether Ole prevents glutamate-induced toxicity in HT-22 hippocampal neuronal cells. The exposure of the glutamate treatment caused neuronal cell death through an alteration of Bax/Bcl-2 expression and translocation of mitochondrial apoptosis-inducing factor (AIF) to the cytoplasm of HT-22 cells. In addition, glutamate induced an increase in dephosphorylation of dynamin-related protein 1 (Drp1), mitochondrial fragmentation, and mitochondrial dysfunction. The pretreatment of Ole decreased Bax expression, increased Bcl-2 expression, and inhibited the translocation of mitochondrial AIF to the cytoplasm. Furthermore, Ole amended a glutamate-induced mitochondrial dynamic imbalance and reduced the number of cells with fragmented mitochondria, regulating the phosphorylation of Drp1 at amino acid residue serine 637. In conclusion, our results show that Ole has a preventive effect against glutamate-induced toxicity in HT-22 hippocampal neuronal cells. Therefore, these data imply that Ole may be an efficient approach for the treatment of neurodegenerative diseases.

Exposure to an environmentally relevant mixture of organochlorine compounds and polychlorinated biphenyls Promotes hepatic steatosis in male Ob/Ob mice.

Hepatic steatosis is recognized as an independent risk factor for the development of cardiovascular disease. While obesity and type 2 diabetes are well-established risk factors in the development of hepatic steatosis, recent studies have revealed exposure to mixtures of persistent organic pollutants (POPs), which are environmental contaminants in various fatty foods, can promote steatosis. Thus, the present study was designed to determine if exposure to a defined mixture of prevalent polychlorinated biphenyls (PCBs) and organochlorine (OC) pesticides or their metabolites promote hepatic steatosis in a genetically induced model of type 2 diabetes, the leptin-deficient ob/ob mouse. Male C57BL/6J wild type (WT) or ob/ob mice were administered an environmentally relevant mixture of PCBs and OCs for 7 weeks via oral gavage. Exposure to POPs did not significantly alter fasting serum glucose or insulin levels. However, POPs exposure significantly increased hepatic triglyceride content in ob/ob animals, while decreasing serum triglyceride levels. This POPs-mediated increase in hepatic triglyceride content did not appear to be associated with significantly increased inflammation in either the liver or adipose. Exposure to POPs significantly induced the expression of cytochrome P450 3a11 in WT animals, yet the expression of this cytochrome was significantly downregulated in ob/ob animals regardless of POPs exposure. Taken together, the present data indicate exposure to an environmentally relevant mixture of both PCBs and OC pesticides in ob/ob mice promotes hepatic steatosis while decreasing hypertriglyceridemia, which demonstrates exposure to a defined mixture of POPs alters systemic lipid metabolism in a genetically induced model of obesity and type 2 diabetes. © 2016 Wiley Periodicals, Inc. Environ Toxicol 32: 1399-1411, 2017.

The comparison of neuroprotective effects of isoliquiritigenin and its Phase I metabolites against glutamate-induced HT22 cell death.

It is becoming increasingly important to investigate drug metabolites to evaluate their toxic or preventive effects after administration of the parent compound. In our previous study, isoliquiritigenin isolated from Glycyrrhizae Radix effectively protected mouse-derived hippocampal neuronal cells (HT22) against 5mM glutamate-induced oxidative stress. However, there is little information on the protective effects of the metabolites of isoliquiritigenin on HT22 cells. In this study, isoliquiritigenin and its Phase I metabolites were prepared and their neuroprotective activities on glutamate-treated HT22 cells were compared. The prepared metabolites were liquiritigenin (1), 2',4,4',5'-tetrahydroxychalcone (2), sulfuretin (3), butein (4), davidigenin (5), and cis-6,4'-dihydroxyaurone (6). Among the six metabolites, 4 showed better neuroprotective effects than the parent compound, isoliquiritigenin. Our study suggests that the neuroprotective effect of isoliquiritigenin could be elevated by its active metabolite 4, which is a chalcone containing a catechol group in the B ring.

Inhibitory effects of polyozellin from Polyozellus multiplex on HMGB1-mediated septic responses.

AIM AND OBJECTIVE: The ubiquitous nuclear protein, high-mobility group box 1 (HMGB1), is released by activated macrophages and human umbilical vein endothelial cells (HUVECs) and functions as a late mediator of experimental sepsis. Polyozellin, which has been reported to have a variety of biological activities including antioxidant and anticancer activity, is the major active compound found in edible mushroom (Polyozellus multiplex). In this study, we investigated the antiseptic effects and underlying mechanisms of polyozellin against HMGB1-mediated septic responses in HUVECs and mice. METHODS: The anti-inflammatory activities of polyozellin were determined by measuring permeability, human neutrophil adhesion and migration, and activation of proinflammatory proteins in HMGB1-activated HUVECs and mice. RESULTS: According to the results, polyozellin effectively inhibited lipopolysaccharide (LPS)-induced release of HMGB1, and suppressed HMGB1-mediated septic responses, such as hyperpermeability, adhesion and migration of leukocytes, and expression of cell adhesion molecules. In addition, polyozellin suppressed the production of tumor necrosis factor-α and interleukin (IL)-6, and the activation of nuclear factor-κB and extracellular signal-regulated kinases 1/2 by HMGB1. CONCLUSION: Collectively, these results indicate that P. multiplex containing polyozellin could be commercialized as functional food for preventing and treatment of various severe vascular inflammatory diseases via inhibition of the HMGB1 signaling pathway.

Mutant disrupted-in-schizophrenia 1 in astrocytes: focus on glutamate metabolism.

Disrupted-in-schizophrenia 1 (DISC1) is a genetic risk factor that has been implicated in major mental disorders. DISC1 binds to and stabilizes serine racemase to regulate production of D-serine by astrocytes, contributing to glutamate (GLU) neurotransmission. However, the possible involvement of astrocytic DISC1 in synthesis, metabolism, reuptake, or secretion of GLU remains unexplored. Therefore, we studied the effects of dominant-negative mutant DISC1 on various aspects of GLU metabolism by using primary astrocyte cultures and hippocampal tissue from transgenic mice with astrocyte-restricted expression of mutant DISC1. Although mutant DISC1 had no significant effects on astrocyte proliferation, GLU reuptake, glutaminase, or glutamate carboxypeptidase II activity, expression of mutant DISC1 was associated with increased levels of alanine-serine-cysteine transporter 2, vesicular glutamate transporters 1 and 3 in primary astrocytes and in the hippocampus, and elevated expression of the NR1 subunit and diminished expression of the NR2A subunit of N-methyl-D-aspartate (NMDA) receptors in the hippocampus, at postnatal day 21. Our findings indicate that decreased D-serine production by astrocytic mutant DISC1 might lead to compensatory changes in levels of the amino acid transporters and NMDA receptors in the context of tripartite synapse.

ß-Secretase (BACE1)-inhibiting C-methylrotenoids from Abronia nana suspension cultures.

Suspension cultures of Abronia nana were established to produce C-methylisoflavones. A new C-methylrotenoid, named abronione A (2), was isolated along with three known rotenoids, boeravinone D (1), boeravinone A methyl ether (3), and mirabijalone D (4). The IC50 values of compounds 1, 2, and 4 on ß-secretase (BACE1) were 4.77, 62.21, and 4.24 µM, respectively, whereas 3 was inactive. At concentrations up to 1.0 mM, the compounds did not inhibit other proteases such as trypsin, chymotrypsin, and elastase, indicating that they were specific inhibitors of ß-secretase. Compounds 1 and 4 were non-competitive inhibitors based on the Dixon plot and with Ki values of 5.01 and 4.28 µM, respectively. At 50 µM, compound 4 inhibited Aß1-42 production by 43.7% in APPSW-N2a cells.

Purification and characterization of antifungal compounds from Lactobacillus plantarum HD1 isolated from kimchi.

Strain HD1 with antifungal activity was isolated from kimchi and identified as Lactobacillus plantarum. Antifungal compounds from Lb. plantarum HD1 were active against food- and feed-borne filamentous fungi and yeasts in a spot-on-the-lawn assay. Antifungal activity of Lb. plantarum HD1 was stronger against filamentous fungi than yeast. Antifungal compounds were purified using solid phase extraction (SPE) and recycling preparative-HPLC. Structures of the antifungal compounds were elucidated by electrospray ionization-mass spectrometry and nuclear magnetic resonance. Active compounds from Lb. plantarum HD1 were identified as 5-oxododecanoic acid (MW 214), 3-hydroxy decanoic acid (MW 188), and 3-hydroxy-5-dodecenoic acid (MW 214). To investigate the potential application of these antifungal compounds for reduction of fungal spoilage in foods, Korean draft rice wine was used as a food model. White film-forming yeasts were observed in control draft rice wine after 11 days of incubation. However, film-forming yeasts were not observed in draft rice wine treated with SPE-prepared culture supernatant of Lb. plantarum HD1 (equivalent to 2.5% addition of culture supernatant) until 27 days of incubation. The addition of antifungal compounds to Korean draft rice wine extended shelf-life up to 27 days at 10 °C without any sterilization process. Therefore, the antifungal activity of Lb. plantarum HD1 may lead to the development of powerful biopreservative systems capable of preventing food- and feed-borne fungal spoilage.

Neuroprotective effects of cerebroprotein hydrolysate and its combination with antioxidants against oxidative stress-induced HT22 cell death.

This study aimed to investigate the neuroprotective effects of cerebroprotein hydrolysate (CPH) against oxidative stress-induced HT22 cell death. Additionally, the effect of antioxidants such as quercetin (QC) and N-acetyl-L-cysteine (NAC) on the neuroprotective activity of CPH was evaluated. The mouse-derived hippocampal neuronal cell line HT22 was pretreated with CPH or a mixture of CPH and QC or NAC. HT22 cell death was induced by either 10 mM glutamate, 2.5 µM amyloid-ß (Aß)25-35, and 300 µM cobalt chloride (CoCl2). As results, CPH effectively alleviated HT22 cell death induced by glutamate, Aß25-35, and CoCl2. In addition, CPH combination with QC augmented cell viability in both glutamate- and Aß25-35-stressed conditions but had no synergic effect on the CoCl2-stressed condition. The synergic effect of CPH and NAC combination was observed under all cell death conditions. The neuroprotective actions of CPH and its combinations with QC or NAC against various oxidative stress-induced HT22 cell deaths were demonstrated, providing a promising strategy for developing CPH preparations for the prevention and/or treatment of neurodegenerative diseases such as Alzheimer's disease.

BET inhibition induces synthetic lethality in PTEN deficient colorectal cancers via dual action on p21CIP1/WAF1.

Loss of PTEN tumor suppressor is an important event during colorectal cancer (CRC) development and is a target for therapeutic exploitation. This study reports that bromodomain and extra-terminal motif (BET) is a synthetic lethal partner of PTEN in CRC. BET inhibition (BETi) selectively induced G1 cell cycle arrest and apoptosis in PTEN-/- CRC. Further, BETi selectively and dose-dependently suppressed the growth of PTEN-/- CRC tumor xenografts in mice and patient-derived organoids. Mechanistically, PTEN-deficient CRC cells elevated the level of cytoplasmic p21CIP1/WAF1 that is hyper-phosphorylated at Thr145 by AKT. BETi suppressed AKT activation in PTEN-deficient CRC cells, followed by the reduction in p21 phosphorylation at Thr145, thereby promoting its nuclear translocation. In addition, BETi suppressed MYC level and this in turn increased the total p21 level in the nuclei. Over-expression of a phospho-mimetic p21 mutant (T145D) significantly rescued the BETi effect on PTEN-deficient CRC. These results suggest that BETi has a dual action on p21: elevating the level of p21 by inhibiting MYC and converting the oncogenic (cytoplasmic) p21 into the tumor-suppressive (nuclear) p21 by inhibiting AKT. Taken together, this study identified the synthetic lethal interaction between PTEN and BET, and provides a potential actionable target for CRC with PTEN loss.