PDK4-mediated metabolic reprogramming is a potential therapeutic target for neovascular age-related macular degeneration.

Age-related macular degeneration (AMD) causes severe blindness in the elderly due to choroidal neovascularization (CNV), which results from the dysfunction of the retinal pigment epithelium (RPE). While normal RPE depends exclusively on mitochondrial oxidative phosphorylation for energy production, the inflammatory conditions associated with metabolic reprogramming of the RPE play a pivotal role in CNV. Although mitochondrial pyruvate dehydrogenase kinase (PDK) is a central node of energy metabolism, its role in the development of CNV in neovascular AMD has not been investigated. In the present study, we used a laser-induced CNV mouse model to evaluate the effects of Pdk4 gene ablation and treatment with pan-PDK or specific PDK4 inhibitors on fluorescein angiography and CNV lesion area. Among PDK isoforms, only PDK4 was upregulated in the RPE of laser-induced CNV mice, and Pdk4 gene ablation attenuated CNV. Next, we evaluated mitochondrial changes mediated by PDK1-4 inhibition using siRNA or PDK inhibitors in inflammatory cytokine mixture (ICM)-treated primary human RPE (hRPE) cells. PDK4 silencing only in ICM-treated hRPE cells restored mitochondrial respiration and reduced inflammatory cytokine secretion. Likewise, GM10395, a specific PDK4 inhibitor, restored oxidative phosphorylation and decreased ICM-induced upregulation of inflammatory cytokine secretion. In a laser-induced CNV mouse model, GM10395 significantly alleviated CNV. Taken together, we demonstrate that specific PDK4 inhibition could be a therapeutic strategy for neovascular AMD by preventing mitochondrial metabolic reprogramming in the RPE under inflammatory conditions.

Structure-Activity Relationship of Synthetic Ginkgolic Acid Analogs for Treating Type 2 Diabetes by PTPN9 Inhibition.

Ginkgolic acid (C13:0) (GA), isolated from Ginkgo biloba, is a potential therapeutic agent for type 2 diabetes. A series of GA analogs were designed and synthesized for the evaluation of their structure-activity relationship with respect to their antidiabetic effects. Unlike GA, the synthetic analog 1e exhibited improved inhibitory activity against PTPN9 and significantly stimulated glucose uptake via AMPK phosphorylation in differentiated 3T3-L1 adipocytes and C2C12 myotubes; it also induced insulin-dependent AKT activation in C2C12 myotubes in a concentration-dependent manner. Docking simulation results showed that 1e had a better binding affinity through a unique hydrophobic interaction with a PTPN9 hydrophobic groove. Moreover, 1e ameliorated palmitate-induced insulin resistance in C2C12 cells. This study showed that 1e increases glucose uptake and suppresses palmitate-induced insulin resistance in C2C12 myotubes via PTPN9 inhibition; thus, it is a promising therapeutic candidate for treating type 2 diabetes.

NMR Studies of the Ion Channel-Forming Human Amyloid-ß with Zinc Ion Concentrations.

Alzheimer's disease (AD) is classified as an amyloid-related disease. Amyloid beta (Aß) is a transmembrane protein known to play a major role in the pathogenesis of AD. These Aß proteins can form ion channels or pores in the cell membrane. Studies have elucidated the structure of the transmembrane domain of Aß ion channels. In addition, various studies have investigated substances that block or inhibit the formation of Aß ion channels. Zinc ions are considered as potential inhibitors of AD. In this study, we focused on the transmembrane domain and some external domains of the Aß protein (hAPP-TM), and solution-state NMR was used to confirm the effect on residues of the protein in the presence of zinc ions. In addition, we sought to confirm the structure and orientation of the protein in the presence of the bicelle using solid-state NMR.

Attention-Based Joint Training of Noise Suppression and Sound Event Detection for Noise-Robust Classification.

Sound event detection (SED) recognizes the corresponding sound event of an incoming signal and estimates its temporal boundary. Although SED has been recently developed and used in various fields, achieving noise-robust SED in a real environment is typically challenging owing to the performance degradation due to ambient noise. In this paper, we propose combining a pretrained time-domain speech-separation-based noise suppression network (NS) and a pretrained classification network to improve the SED performance in real noisy environments. We use group communication with a context codec method (GC3)-equipped temporal convolutional network (TCN) for the noise suppression model and a convolutional recurrent neural network for the SED model. The former significantly reduce the model complexity while maintaining the same TCN module and performance as a fully convolutional time-domain audio separation network (Conv-TasNet). We also do not update the weights of some layers (i.e., freeze) in the joint fine-tuning process and add an attention module in the SED model to further improve the performance and prevent overfitting. We evaluate our proposed method using both simulation and real recorded datasets. The experimental results show that our method improves the classification performance in a noisy environment under various signal-to-noise-ratio conditions.

Structural and Mechanismic Studies of Lactophoricin Analog, Novel Antibacterial Peptide.

Naturally derived antibacterial peptides exhibit excellent pharmacological action without the risk of resistance, suggesting a potential role as biologicals. Lactophoricin-I (LPcin-I), found in the proteose peptone component-3 (PP3; lactophorin) of bovine milk, is known to exhibit antibiotic activity against Gram-positive and Gram-negative bacteria. Accordingly, we derived a new antibacterial peptide and investigated its structure-function relationship. This study was initiated by designing antibacterial peptide analogs with better antibacterial activity, less cytotoxicity, and shorter amino acid sequences based on LPcin-I. The structural properties of antibacterial peptide analogs were investigated via spectroscopic analysis, and the antibacterial activity was confirmed by measurement of the minimal inhibitory concentration (MIC). The structure and mechanism of the antibacterial peptide analog in the cell membrane were also studied via solution-state nuclear magnetic resonance (NMR) and solid-state NMR spectroscopy. Through 15N one-dimensional and two-dimensional NMR experiments and 31P NMR experiments, we suggest the 3D morphology and antibacterial mechanism in the phospholipid bilayer of the LPcin analog. This study is expected to establish a system for the development of novel antibacterial peptides and to establish a theoretical basis for research into antibiotic substitutes.

Electrochemical lithiation performance and characterization of silicon-graphite composites with lithium, sodium, potassium, and ammonium polyacrylate binders.

Poly(acrylic acid) (PAH), which is a water soluble polycarboxylic acid, is neutralized by adding different amounts of LiOH, NaOH, KOH, and ammonia (NH4OH) aqueous solutions to fix neutralization degrees. The differently neutralized polyacid, alkali and ammonium polyacrylates are examined as polymeric binders for the preparation of Si-graphite composite electrodes as negative electrodes for Li-ion batteries. The electrode performance of the Si-graphite composite depends on the alkali chemicals and neutralization degree. It is found that 80% NaOH-neutralized polyacrylate binder (a pH value of the resultant aqueous solution is ca. 6.7) is the most efficient binder to enhance the electrochemical lithiation and de-lithiation performance of the Si-graphite composite electrode compared to that of conventional PVdF and the other binders used in this study. The optimum polyacrylate binder highly improves the dispersion of active material in the composite electrode. The binder also provides the strong adhesion, suitable porosity, and hardness for the composite electrode with 10% (m/m) binder content, resulting in better electrochemical reversibility. From these results, the factors of alkali-neutralized polyacrylate binders affecting the electrode performance of Si-graphite composite electrodes are discussed.

IFN-γ inhibits basal and α-MSH-induced melanogenesis.

Inflammatory cytokines are closely related to pigmentary changes. In this study, the effects of IFN-γ on melanogenesis were investigated. IFN-γ inhibits basal and α-MSH-induced melanogenesis in B16 melanoma cells and normal human melanocytes. MITF mRNA and protein expressions were significantly inhibited in response to IFN-γ. IFN-γ inhibited CREB binding to the MITF promoter but did not affect CREB phosphorylation. Instead, IFN-γ inhibited the association of CBP and CREB through the increased association between CREB binding protein (CBP) and STAT1. These findings suggest that IFN-γ inhibits both basal and α-MSH-induced melanogenesis by inhibiting MITF expression. The inhibitory action of IFN-γ in α-MSH-induced melanogenesis is likely to be associated with the sequestration of CBP via the association between CBP and STAT1. These data suggest that IFN-γ plays a role in controlling inflammation- or UV-induced pigmentary changes.

Surface modification of polypropylene separators in lithium-ion batteries using inductively coupled plasma treatment.

We describe herein an improvement in the surface wettability of plasma-treated separators for use in lithium-ion batteries. We treated the separators with an O2/Ar inductively coupled plasma to increase their surface energy. The plasma treatment on the separator and plasma diagnostic experiments were performed in an inductively coupled plasma (ICP) reactor. The fraction of Ar in the O2/Ar plasma was changed from 0% to 100%. The plasma diagnostics were performed using optical emission spectroscopy and a double Langmuir probe. To confirm the morphological change of the separator membrane by the plasma treatment, we used the scanning electron microscopy. The surface energy measurements were performed using the drop method. We found that the plasma treatment transformed the separator from a hydrophobic membrane to a hydrophilic one, thereby achieving high separator wettability. After the treatment of the separators with O2/Ar plasma, the batteries exhibited better cycle performance and rate capacity than those employing the untreated ones.

Etching characteristics and mechanism of SiN(x) films for nano-devices in CH2F2/O2/Ar inductively coupled plasma: effect of O2 mixing ratio.

Etching characteristics and mechanisms of low-temperature SiN(x) thin films for nano-devices in CH2F2/O2/Ar inductively-coupled plasmas were studied. The etching rates of SiN(x) thin films as well as the etching selectivities over Si and photoresist were measured in the range of 25-75% O2 in a feed gas at fixed CH2F2 content (25%), gas pressure (6 mTorr), input power (900 W), bias power (200 W), and total gas flow rate (40 sccm). Plasma parameters were analyzed using the Langmuir probe diagnostics and optical emission spectroscopy. The chemical states of the etched surfaces were examined by the X-ray photoelectron spectroscopy. It was found that the non-monotonic (with a maximum at about 50-60% O2) SiN(x) etching rate does not correlate with monotonically decreasing F atom flux and ion energy flux. It was proposed that, under the given set of experimental conditions, the SiN(x) etching process is also controlled by the O and H atom fluxes through the destruction of the fluorocarbon polymer layer.

Crop-derived polysaccharides as binders for high-capacity silicon/graphite-based electrodes in lithium-ion batteries.

Rice to power: Amylopectin is a major component of agricultural products such as corn, potato, and rice. Silicon-graphite electrodes are prepared by using slurries of these polysaccharides as binders. Compared to the conventionally used binder PVdF, they exhibit drastically improved electrode performance in Li cells. The improved performance is coupled to the degree of branching.

Chemotherapy-induced myelotoxicity and incidence of lung metastasis in an animal model.

We examined how chemotherapy-induced myelotoxicity and the associated leukopaenia affect cancer metastasis in an animal model. Myelotoxicity was induced by a single injection of 5-fluorouracil (5-FU) or Cisplatin, administered to 7-week-old BALB/c mice. CT-26 murine colon carcinoma cells were injected into the lateral tail vein on days 0, 1, 3, 5, and 7 after anticancer drug injection. On day 14 after cancer cell injection, the number of pulmonary colonies was measured in a double-blind setting. Compared with Cisplatin, 5-FU induced severe leukopaenia and bone marrow suppression, while on day 5, both drugs induced severe myelotoxicity. The number of pulmonary colonies did not correlate with the severity of leukopaenia, regardless of the type or time of drug injection, except in the group pretreated with Cisplatin (3 days prior to cancer cell injection). Our results suggest that chemotherapy-induced myelotoxicity does not increase the incidence of cancer metastasis in this animal model.

Antifibrotic effects of CGX, a traditional herbal formula, and its mechanisms in rats.

AIM: CGX is a modification of a traditional herbal medicine for "liver cleaning," which is used to treat various chronic liver disorders in oriental clinics. This study investigated the antifibrotic effects and associated mechanisms of CGX. MATERIALS AND METHODS: Liver fibrosis was induced in rats by dimethylnitrosamine (DMN; 10 mg kg(-1), ip) injection on 3 consecutive days per week for 4 weeks. CGX (100 or 200 mg kg(-1), po) was administrated once a day for 4 weeks. Three cell lines (HepG2, RAW 264.7, and HSC-T6) were used to examine its mechanisms. RESULTS: CGX treatment dramatically ameliorated the change in liver and spleen weight and serum albumin (p<0.01), aspartate transaminase (p<0.01), alanine transaminase (p<0.01), alkaline phosphatase (p<0.01), and total bilirubin (p<0.01) levels. Histopathologically, CGX administration decreased necrosis, inflammatory cell infiltration, and collagen accumulation. The antifibrotic effects of CGX were confirmed from hydroxyproline determination and the reduction in the numbers of activated hepatic stellate cells. In addition, antioxidant proteins, glutathione content, and glutathione peroxidase, catalase, and superoxide dismutase activities were maintained in the CGX-treated groups compared with the DMN group. CGX downregulated fibrosis-related genes (inducible nitric oxide synthase, tumor necrosis factor-alpha, transforming growth factor-beta, connective tissue growth factor, and platelet-derived growth factor-beta) and decreased the protein levels of profibrotic cytokines (transforming growth factor-beta and platelet-derived growth factor-beta) in liver tissues. In the cell line-based studies, CGX showed supportive effects, such as the protection of hepatocytes from CCl(4)-toxicity, inhibition of NO production in RAW 264.7 cells, and inactivation of hepatic stellate cells. CONCLUSION: These results demonstrated the antifibrotic effects of CGX and the corresponding mechanisms associated with sustaining the antioxidative system and inhibiting hepatic stellate cell activation via the downregulation of fibrogenic cytokines.

Antioxidative and hepatoprotective effect of CGX, an herbal medicine, against toxic acute injury in mice.

AIM: CGX, a modified traditional Chinese herbal drug whose name means "liver cleaning," is used to treat various liver disorders. This study investigated the protective effects of CGX and its mechanisms. MATERIAL AND METHODS: After pretreating ICR mice twice daily with CGX (po, 50 or 100mg/kg) or distilled water for three consecutive days, acute liver injury was induced by a single injection of CCl(4) (ip, 10mL/kg of 0.2% in olive oil) (n=8 per group). RESULTS: Pretreatment with CGX significantly attenuated the elevation in biochemical parameters, such as alanine transaminase (ALT), aspartate transaminase (AST), and lactate dehydrogenase (LDH) in serum, and the malondialdehyde concentrations in liver tissue. Pretreatment with CGX significantly restored the reduction of catalase activity and glutathione (GSH) content, but not superoxide dismutase (SOD) activity, and it inhibited the CCl(4)-induced high expression of iNOS and TNF-alpha in hepatic tissue. CONCLUSION: This study showed that CGX has hepatoprotective effects against free radical-induced acute injury via primarily antioxidative properties.

Soluble components of Hericium erinaceum induce NK cell activation via production of interleukin-12 in mice splenocytes.

AIM: To investigate the immunoregulatory functions of water extracts of Hericium erinaceum (WEHE) focusing on natural killer (NK) cell-based anticancer activities. METHODS: Mouse splenocytes or purely isolated NK cells were stimulated with 1-100 mg/L WEHE for 24 h followed by co-culture with (51)Cr-labeled Yac-1 cells for 4 h, then NK cell-derived cytolytic activity was measured using a radio-release assay. Neutralizing antibodies against mouse interleukin-12 (IL-12) were added into the WEHE-stimulated splenocytes, thereafter, cytotoxicity was measured to examine the involvement of IL-12. RT-PCR and ELISA analyses were performed to confirm the induction of transcription and the translation of IL-12 and interferon-gamma (IFN-gamma) in the WEHE-treated splenocytes. RESULTS: WEHE enhanced the cytolytic activity of total splenocytes towards Yac-1 cells in a dose-dependent manner. However, this activation was not observed when the NK cells isolated from the splenocytes were treated with WEHE. Furthermore, the treatment with antibodies against IL-12 abolished the effect of WEHE on splenocyte-derived cytolytic activity. RT-PCR and ELISA analyses showed the induction of IL-12 and IFN-gamma in the WEHE-treated splenocytes. CONCLUSION: WEHE indirectly activates the cytolytic ability of NK cells via the induction of IL-12 in total splenocytes, and possibly via other immuno-mediators or cellular components.

Toxicological study of the hepatotherapeutic herbal formula, chunggan extract, in beagle dogs.

AIM: To evaluate the pharmaceutical safety of a Chinese herbal formula, chunggan extract (CGX), traditionally prescribed as a hepatotherapeutic drug via systemic acute and subacute toxicological study. METHODS: Twenty male dogs and 20 female dogs were fed doses 50 times and 4 times greater than the clinically-recommended drug dosages in an acute and a subacute toxicological study, respectively. Adverse effects were examined by comparing the differences between normal and drug-administered groups using clinical signs, necropsies, histopathologic findings, haematology, urinalysis, and biochemical analysis. RESULTS: In the acute study no change in the body weight, diarrhoea, apetite, mortality rate and histopathology of major organs was observed in male or female dogs with a single administration of CGX at 5 g/kg. No drug-induced abnormalities at analysis of histopathology, haematology, urinalysis, and biochemistry were found with any dose of this drug. CONCLUSION: CGX is supposed to be very safe when used in a clinical application with a wide therapeutic index.

An herbal formula, CGX, exerts hepatotherapeutic effects on dimethylnitrosamine-induced chronic liver injury model in rats.

AIM: To evaluate the therapeutic effect of Chunggan extract (CGX), a modified traditional Chinese hepatotherapeutic herbal, on the dimethylnitrosamine (DMN)-induced chronic liver injury model in rats. METHODS: Liver injuries were induced in Wistar rats by injection of DMN (ip, 10 mg/mL per kg) for 3 consecutive days per week for 4 wk. The rats were administered with CGX (po, 100 or 200 mg/kg per day) or distilled water as a control daily for 4 wk starting from the 15(th) d of the DMN treatment. Biochemical parameters (serum albumin, bilirubin, ALP, AST and ALT), lipid peroxides, hydroxyproline, as well as histological changes in liver tissues were analyzed. In addition, gene expression of TNF-alpha, TGF-beta, TIMP-1, TIMP-2, PDGF-beta, and MMP-2, all of which are known to be associated with liver fibrosis, were analyzed using real-time PCR. RESULTS: CGX administration restored the spleen weight to normal after having been increased by DMN treatment. Biochemical analysis of the serum demonstrated that CGX significantly decreased the serum level of ALP (P < 0.05), ALT (P < 0.01), and AST (P < 0.01) that had been elevated by DMN treatment. CGX administration moderately lowered lipid peroxide production and markedly lowered hydroxyproline generation caused by DMN treatment in accordance with histopathological examination. DMN treatment induced a highly up-regulated expression of TNF-alpha, TGF-beta, TIMP-1, TIMP-2, PDGF-beta, and MMP-2. Of these, the gene expression encoding PDGF-beta and MMP-2 was still further enhanced 2 wk after secession of the 4-wk DMN treatment, and was remarkably ameliorated by CGX administration. CONCLUSION: CGX exhibits hepatotherapeutic proper-ties against chronic hepatocellular destruction and consequential liver fibrosis.