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In this study, an iridium oxide (IrO2) inverse-opal membrane-electrode assembly (inverse-opal MEA) was fabricated via the decal-transfer method for an anode in polymer-electrolyte membrane water electrolysis (PEMWE) to decrease the loading of the noble catalyst. Electrodeposition parameters including current and total number of cycles were investigated to achieve the IrO2 inverse-opal electrode. The inverse-opal MEA with ultra-low loading exhibited outstanding performance that exceeded or was comparable to that obtained in other PEMWE studies. Additionally, it exhibited higher performance and lower ohmic and charge-transfer resistance when compared with that of commercial IrO2. Furthermore, the performance corresponded to the highest mass activity reported to date since the loading in the inverse-opal MEA was ultra-low. This was because the inverse-opal structure improved electron transfer owing to the interconnected pores and increased the surface area due to high porosity, thereby leading to the enhanced utilization of the catalyst.

An earth-abundant and feasible air cathode electrocatalyst is of importance for energy devices including fuel cells and metal–air batteries. Herein, hierarchically porous S,N-co-doped carbon materi...

Mesenchymal stem cells (MSCs) have the function of repairing damaged tissue, which is known to be mediated by the secretome, the collection of secretory materials shed from MSCs. Adjusting the culture conditions of MSCs can lead to a significant difference in the composition of the secretome. It was hypothesized that pre-sensitization of MSCs with specific disease-causing agents could harness MSCs to release the therapeutic materials specialized for the disease. To validate this hypothesis, the present study aimed to generate a 'disease-specific secretome' for hepatitis caused by hepatitis B virus using hepatitis BX antigen (HBx) as a disease-causing material. Secretary materials (HBx-IS) were collected following the stimulation of adipose-derived stem cells (ASCs) with 100-fold diluted culture media of AML12 hepatocytes that had been transfected with pcDNA-HBx for 24 h. An animal model of hepatitis B was generated by injecting HBx into mice, and the mice were subsequently intravenously administered a control secretome (CS) or HBx-IS. Compared with the CS injection, the HBx-IS injection significantly reduced the serum levels of interleukin-6 and tumor necrosis factor-α (pro-inflammatory cytokines). Western blot analysis and immunohistochemistry of the liver specimens revealed that the HBx-IS injection led to a higher expression of liver regeneration-related markers, including hepatocyte growth factor and proliferating cell nuclear antigen, a lower expression of pro-apoptotic markers, such as cleaved caspase 3 and Bim in mouse livers, and a lower expression of pro-inflammatory markers (F4/80 and CD68) compared to the CS injection. HBx-IS exhibited higher liver regenerative, anti-inflammatory and anti-apoptotic properties, particularly in the mouse model of hepatitis B compared to CS. This suggests that the secretome obtained by stimulating ASCs with disease-causing agents may have a more prominent therapeutic effect on the specific disease than the naïve secretome.

Currently, there is no appropriate treatment option for patients with sorafenib-resistant hepatocellular carcinoma (HCC). Meanwhile, pronounced anticancer activities of newly-developed mitochondria-accumulating self-assembly peptides (Mito-FF) have been demonstrated. This study intended to determine the anticancer effects of Mito-FF against sorafenib-resistant Huh7 (Huh7-R) cells. Compared to sorafenib, Mito-FF led to the generation of relatively higher amounts of mitochondrial reactive oxygen species (ROS) as well as the greater reduction in the expression of antioxidant enzymes (P

Purpose mTORC1 and mTORC2 inhibition by Ku-0063794 could confer profound anticancer effects against cancer cells because it eliminates feedback activation of Akt. Herein, we aimed to determine anticancer effects of docetaxel and Ku-0063794, individually or in combination, against breast cancer cells, especially triple-negative breast cancer (TNBC) cells.Materials and Methods MCF-7 breast cancer and MDA-MB-231 TNBC cell lines for in vitro studies and mouse xenograft model for in vivo studies were used to investigate the effect of docetaxel, Ku-0063794, or their combination.Results In the in vitro experiments, combination therapy synergistically reduced cell viability and induced higher apoptotic cell death in breast cancer cells than the individual monotherapies (p < 0.05). Western blot analysis and flow cytometric analysis showed that the combination therapy induced higher apoptotic cell death than the individual monotherapies (p < 0.05). In the in vivo experiment, docetaxel and Ku-0063794 combination therapy reduced the growth of MDA-MB-231 cells xenografted in the nude mice better than in the individual monotherapies (p < 0.05). Immunohistochemistry showed that the combination therapy induced the highest expression of cleaved caspase-3 and the lowest expression of Bcl-xL in the MDA-MB-231 cells xenografted in the nude mice (p < 0.05). Western blot analysis and immunofluorescence, incorporating both in vitro and in vivo experiments, consistently validated that unlike individual monotherapies, docetaxel and Ku-0063794 combination therapy significantly inhibited epithelial-mesenchymal transition (EMT) and autophagy (p < 0.05).Conclusion These data suggest that docetaxel and Ku-0063794 combination therapy has higher anticancer activities over individual monotherapies against MDA-MB-231 TNBC cells through a greater inhibition of autophagy and EMT.

Here, we provide the possibility of a novel chemotherapeutic agent against gastric cancer cells, comprising the combination of 5-fluorouracil (5-FU) and a mitochondria-targeting self-assembly peptide, which is a phenylalanine dipeptide with triphenyl phosphonium (Mito-FF). The anticancer effects and mechanisms of 5-FU and Mito-FF, individually or in combination, were compared through both in vitro and in vivo models of gastric cancer. Our experiments consistently demonstrated that the 5-FU and Mito-FF combination therapy was superior to monotherapy with either, as manifested by both higher reduction of proliferation as well as an induction of apoptotic cell death. Interestingly, we found that combining 5-FU with Mito-FF leads to a significant increase of reactive oxygen species (ROS) and reduction of antioxidant enzymes in gastric cancer cells. Moreover, the inhibition of ROS abrogated the pro-apoptotic effects of combination therapy, suggesting that enhanced oxidative stress could be the principal mechanism of the action of combination therapy. We conclude that the combination of 5-FU and Mito-FF exerts potent antineoplastic activity against gastric cancer cells, primarily by promoting ROS generation and suppressing the activities of antioxidant enzymes.

Phosphate overload contributes to mineral bone disorders that are associated with crystal nephropathies. Phytate, the major form of phosphorus in plant seeds, is known as an indigestible and of negligible nutritional value in humans. However, the mechanism and adverse effects of high-phytate intake on Ca2+and phosphate absorption and homeostasis are unknown. Here, we show that excessive intake of phytate along with a low-Ca2+diet fed to rats contributed to the development of crystal nephropathies, renal phosphate wasting, and bone loss through tubular dysfunction secondary to dysregulation of intestinal calcium and phosphate absorption. Moreover, Ca2+supplementation alleviated the detrimental effects of excess dietary phytate on bone and kidney through excretion of undigested Ca2+-phytate, which prevented a vicious cycle of intestinal phosphate overload and renal phosphate wasting while improving intestinal Ca2+bioavailability. Thus, we demonstrate that phytate is digestible without a high-Ca2+diet and is a risk factor for phosphate overloading and for the development of crystal nephropathies and bone disease.

Tumor necrosis factor-&alpha, (TNF-&alpha, )-driven inflammatory reaction plays a crucial role in the initiation of liver fibrosis. We herein attempted to design genetically engineered adipose-derived stem cells (ASCs) producing etanercept (a potent TNF-&alpha, inhibitor), and to determine the anti-fibrotic potential of the secretome released from the etanercept-synthesizing ASCs (etanercept-secretome). First, we generated the etanercept-synthesizing ASCs by transfecting the ASCs with mini-circle plasmids containing the gene insert encoding for etanercept. We subsequently collected the secretory material released from the etanercept-synthesizing ASCs and determined its anti-fibrotic effects both in vitro (in thioacetamide [TAA]-treated AML12 and LX2 cells) and in vivo (in TAA-treated mice) models of liver fibrosis. We observed that while etanercept-secretome increased the viability of the TAA-treated AML12 hepatocytes (p = 0.021), it significantly decreased the viability of the TAA-treated LX2 HSCs (p = 0.021). In the liver of mice with liver fibrosis, intravenous administration of the etanercept-secretome induced significant reduction in the expression of both fibrosis-related and inflammation-related markers compared to the control group (all Ps &lt, 0.05). The etanercept-secretome group also showed significantly lower serum levels of liver enzymes as well as pro-inflammatory cytokines, such as TNF-&alpha, (p = 0.020) and IL-6 (p = 0.021). Histological examination of the liver showed the highest reduction in the degree of fibrosis in the entanercept-secretome group (p = 0.006). Our results suggest that the administration of etanercept-secretome improves liver fibrosis by inhibiting TNF-&alpha, driven inflammation in the mice with liver fibrosis. Thus, blocking TNF-&alpha, driven inflammation at the appropriate stage of liver fibrosis could be an efficient strategy to prevent fibrosis.

An ideal oxygen reduction catalyst for use in fuel cells should exhibit both long-term durability and high activity. In this study, to increase the durability of highly loaded platinum- and platinum-nickel alloy catalysts possessing different types of carbon supports, a nitrogen-doped carbon shell was introduced on the catalyst surface through dopamine coating. As the catalyst surfaces were altered following shell formation, the ionomer contents of the catalyst inks were adjusted to optimise the three-phase boundary formation. Single cell tests were then conducted on these inks by applying them in a membrane electrolyte assembly. Furthermore, to confirm the durability of the catalysts under accelerated conditions, the operation was continued for 200 h at 70 °C and at a relative humidity of 100%. Transmission electron microscopy and electrochemical analysis were conducted before and after the durability tests, and the observed phenomena were discussed for catalysts bearing different types of carbon supports.

In this study, by treating not only the membrane but also the whole membrane electrode assembly (MEA) with KOH solution prior to incorporation in alkaline anion exchange membrane fuel cells, an ionic pathway for hydroxide conduction has optimized in the catalyst layer. This lowers the ohmic resistance of the KOH-treated MEA as detected by the polarization curve and impedance spectroscopy analysis. The process has greater advantage for non-platinum group metal (PGM) catalysts than PGM catalysts, because of the lower active site density and consequent high loading required for non-PGM catalysts.

We synthesized ordered mesoporous Fe/N/C with highly active Fe-N x /C sites denoted as m-FePhen-C as a non-precious metal catalyst (NPMC) for the oxygen reduction reaction in fuel cells. This was the first study that incorporated a catalyst precursor with Fe-N coordination directly in a simple block co-polymer-assisted soft-template method for the synthesis of mesoporous Fe/N/C. The synthesized catalyst (m-FePhen-C) showed a high catalytic performance comparable to that of Pt/C in half-cell tests, and a membrane electrode assembly (MEA) with an m-FePhen-C cathode exhibited 40% higher power density than did an MEA with a commercial Pt/C cathode in single-cell tests, with comparable electrode thicknesses. This result is highly meaningful in that generation of the Fe-N x /C active sites and formation of ordered mesoporous structure were achieved simultaneously in the simple soft-template-assisted process, and in that the advantages of mesoporous structure with appropriate pore size in metal-containing NPMC were elucidated for high-performance MEAs.

The large-area membrane-electrode assembly (MEA) has been fabricated using the decal transfer method with a methanol (MeOH)-based PtRu/C catalyst slurry. The stability of slurry dispersion is important when using a large-area decal transfer method to ensure the integrity of the electrode. In order to prepare stable and well dispersed catalyst slurry, a suitable solvent for the PtRu/C catalyst should be selected. We considered the physical properties of various organic solvents, including ionomer solubility, dielectric constant, and catalyst particle surface physical properties. We found that the MeOH-based PtRu/C slurry dispersion showed the best stability and dispersibility of catalyst–ionomer agglomerates. It was also confirmed that the MeOH-based slurry has the most suitable characteristics for coating the slurry on the substrate film. The decal technique-based MEA using this slurry showed excellent performance when compared with the spray method-based MEA. Furthermore, the large-area PtRu/C MEA with an active area of 51.84 cm2 was fabricated and excellent performance was realized even when a reforming gas was used.

Multicomponent catalysts such as RuOs/C binary electrocatalysts and Pt-modified RuOs/C (Pt-RuOs/C) ternary electrocatalysts were prepared using the sodium borohydride reduction method for use as anode materials in proton exchange membrane fuel cells (PEMFCs). The electrocatalyst particles, of size 3–4 nm, were uniformly dispersed on carbon supports and showed a similar performance to commercial Pt/C in single cell tests. In this study, we demonstrate the use of multicomponent materials with no Pt or a very low level of Pt as potential anode catalysts in an actual PEMFC device. The polarization test results showed that, when used in membrane-electrode assemblies (MEAs) within a PEMFC, the RuOs/C binary electrocatalysts exhibited a significantly enhanced electrochemical performance for hydrogen oxidation. In addition, Pt-RuOs/C revealed a similar performance to that of commercial Pt/C; the new electrocatalyst, in particular, showed excellent Pt mass activity. These results indicate that the RuOs/C catalyst is potentially an alternative anode electrocatalyst for PEMFCs.

Purpose Everolimus only inhibits mammalian target of rapamycin complex 1 (mTORC1), whereas Ku0063794 inhibits both mTORC1 and mTORC2. Although they have similar anticancer effects, their combination has a synergistic effect against hepatocellular carcinoma (HCC) cells. We aimed to determine the mechanism underlying the synergistic effects of everolimus and Ku0063794 associated with autophagy in HCC cells. Materials and methods We compared the effects of everolimus and Ku0063794, individually or in combination, on both the in vitro and in vivo models of HCCs. Results HepG2 cells treated with both agents had significantly lower rates of cell proliferation and higher apoptosis than the individual monotherapies (p l 0.05). Autophagic studies consistently indicated that, unlike the monotherapies, the combination therapy significantly reduced autophagy (p l 0.05). Autophagic blockage directly promoted the pro-apoptotic effects of combination therapy, suggesting autophagy as the survival mechanism of HCC cells. Unlike the monotherapies, combination therapy showed the potential to inhibit sirtuin 1 (SIRT1), the positive regulator of autophagy. SIRT1 overexpression abrogated the autophagy-inhibiting and pro-apoptotic effects of combination therapy. In a nude mouse xenograft model, the shrinkage of tumors was more prominent in mice treated with combination therapy than in mice treated with the respective monotherapies (p l 0.05). The immunohistochemical and immunofluorescence stains of the tumor obtained from the xenograft model showed that combination therapy had the potential of reducing autophagy and promoting apoptosis. Conclusion The combination of everolimus and Ku0063794 potentiates anticancer effects on HCCs through a decrease in autophagy, which is prompted by SIRT1 downregulation.

Significance Insulin resistance is a metabolic disorder in which target cells fail to respond to physiological levels of circulating insulin, leading to hyperinsulinemia and glucose intolerance. The molecular mechanism underlying insulin resistance is still largely unknown. Here, we found that intracellular Ca2+ overloading in obesity attenuates insulin-stimulated phosphorylation of protein kinase B and its downstream signaling by preventing membrane localization of various pleckstrin homology (PH) domains. When at high intracellular levels, Ca2+ binds tightly with phosphoinositides to yield Ca2+-phosphoinositides (PIPs), abrogating the membrane targeting of PH domains and disrupting insulin signaling. Thus, we identified a previously unknown physiological function of intracellular Ca2+ as a critical negative regulator of insulin signaling, especially through the formation of Ca2+-PIPs., Insulin resistance, a key etiological factor in metabolic syndrome, is closely linked to ectopic lipid accumulation and increased intracellular Ca2+ concentrations in muscle and liver. However, the mechanism by which dysregulated intracellular Ca2+ homeostasis causes insulin resistance remains elusive. Here, we show that increased intracellular Ca2+ acts as a negative regulator of insulin signaling. Chronic intracellular Ca2+ overload in hepatocytes during obesity and hyperlipidemia attenuates the phosphorylation of protein kinase B (Akt) and its key downstream signaling molecules by inhibiting membrane localization of pleckstrin homology (PH) domains. Pharmacological approaches showed that elevated intracellular Ca2+ inhibits insulin-stimulated Akt phosphorylation and abrogates membrane localization of various PH domain proteins such as phospholipase Cδ and insulin receptor substrate 1, suggesting a common mechanism inhibiting the membrane targeting of PH domains. PH domain-lipid overlay assays confirmed that Ca2+ abolishes the binding of various PH domains to phosphoinositides (PIPs) with two adjacent phosphate groups, such as PI(3,4)P2, PI(4,5)P2, and PI(3,4,5)P3. Finally, thermodynamic analysis of the binding interaction showed that Ca2+-mediated inhibition of targeting PH domains to the membrane resulted from the tight binding of Ca2+ rather than PH domains to PIPs forming Ca2+-PIPs. Thus, Ca2+-PIPs prevent the recognition of PIPs by PH domains, potentially due to electrostatic repulsion between positively charged side chains in PH domains and the Ca2+-PIPs. Our findings provide a mechanistic link between intracellular Ca2+ dysregulation and Akt inactivation in insulin resistance.

The Fe–N–C-based carbon materials, which are generally formed by high-temperature annealing, have been highlighted as a promising alternative to expensive Pt electrocatalysts for oxygen reduction reaction. However, the delicate formation of active sites remains an issue because of decomposition and transformation of the macrocycle during heat treatment. Accordingly, we developed a low-temperature and gram-scale approach to synthesizing iron phthalocyanine (Pc)-embedded two-dimensional carbon sheets by annealing at 450 °C. The low-temperature annealing process, which is motivated by the synthesis of carbon nanoribbons, is suitable for maintaining the Fe–N–C structure while enhancing coupling with carbon. Our two-dimensional carbon sheets show higher ORR activity than commercial Pt catalyst in alkaline media. Furthermore, the feasibility of real application to alkaline membrane electrolyte fuel cell is verified by superior volumetric current density. In durability point of view, the initial activity is reta...

Accumulation of tissue macrophages is a significant characteristic of disease-associated chronic inflammation, and facilitates the progression of disease pathology. However, the functional roles of these bone marrow-derived macrophages (BMDMs) in aging are unclear. Here, we identified agedependent macrophage accumulation in the bone marrow, showing that aging significantly increases the number of M1 macrophages and impairs polarization of BMDMs. We found that age-related dysregulation of BMDMs is associated with abnormal overexpression of the anti-inflammatory interleukin-10. BMDM dysregulation in aging impairs the expression levels of pro-inflammatory cytokines and genes involved in B-cell maturation and activation. Phagocytosis of apoptotic Jurkat cells by BMDMs was reduced because of low expression of phagocytic receptor CD14, indicating that increased apoptotic cells may result from defective phagocytosis of apoptotic cells in the BM of aged mice. Therefore, CD14 may represent a promising target for preventing BMDM dysregulation, and macrophage accumulation may provide diagnostic and therapeutic clues. [BMB Reports 2017; 50(1): 43-48].

There is lots of evidence to support the critical involvement of mTOR signaling in the carcinogenesis of hepatocellular carcinoma (HCC). However, it has not been determined how the roles of individual mTORC1 and mTORC2 inhibitors played in the HCC therapeutics. We thus compared the effects of everolimus, Ku0063794, and a combination of the two therapies on HCC cells, using various in vitro studies (HepG2, Hep3B, and Huh7 cells), ex vivo culturing of HCC tissues obtained from patients, and the in vivo mouse xenograft model of HCC cells. Our in vitro, ex vivo, and in vivo experiments consistently demonstrated that everolimus and Ku0063794 combination therapy was superior to individual monotherapies, as manifested by higher reduction of proliferation, migration, and invasion of HCC cells, and the higher inhibition of EMT process as well. Although individual monotherapies could not inhibit SIRT1 (positive regulator of EMT) expression, the combination therapy significantly inhibited SIRT1 expression. However, overexpression of SIRT1 mitigated the EMT-inhibiting effect of the combination therapy, suggesting that the combination therapy inhibits the EMT by way of suppressing SIRT1 expression. Therefore, when considering everolimus as an anti-HCC agent, the improved anticancer effects provided by combining it with an inhibitor of both mTORC1 and mTORC2 should be recognized.

Phosphate overload contributes to mineral bone disorders associated with crystal nephropathies. Phytate, the major form of phosphorus in plant seeds, is known as an indigestible and negligible in humans. However, the mechanism and adverse effects of high-phytate intake on Ca2+and phosphate absorption and homeostasis are unknown. Here we show that excessive intake of phytate with a low-Ca2+diet fed to rats contributed to the development of crystal nephropathies, renal phosphate wasting, and bone loss through tubular dysfunction secondary to dysregulation of intestinal calcium and phosphate absorption. Moreover, Ca2+supplementation alleviated the detrimental effects of excess dietary phytate on bone and kidney through excretion of undigested Ca2+-phytate, which prevented a vicious cycle of intestinal phosphate overload and renal phosphate wasting while improving intestinal Ca2+bioavailability. Thus, we demonstrate that phytate is digestible without a high-Ca2+diet and a risk factor for phosphate overloading and developing crystal nephropathies and bone disease.

The limitations of stem cells have led researchers to investigate the secretome, which is the secretory materials in stem cells, since the principal mechanism of action of stem cells is mediated by the secretome. In this study, we determined the antifibrotic potential of the secretome released from miR-150-transfected adipose-derived stromal cells (ASCs). The secretome released from ASCs that were transfected with antifibrotic miR-150 was obtained (referred to as the miR-150 secretome). To validate the antifibrotic effects of the miR-150 secretome, we generated in vitro and in vivo models of liver fibrosis by treating human hepatic stellate cells (LX2 cells) with thioacetamide (TAA) and subcutaneous injection of TAA into mice, respectively. In the in vitro model, more significant reductions in the expression of fibrosis-related markers, such as TGFβ, Col1A1, and α-SMA, were observed by using the miR-150 secretome than the control secretome, specifically in TAA-treated LX2 cells. In the in vivo model, infusion of the miR-150 secretome into mice with liver fibrosis abrogated the increase in serum levels of systemic inflammatory cytokines, such as IL-6 and TNF-α, and induced increased expression of antifibrotic, proliferation, and antioxidant activity markers in the liver. Our in vitro and in vivo experiments indicate that the miR-150 secretome is superior to the naive secretome in terms of ameliorating liver fibrosis, minimizing systemic inflammatory responses, and promoting antioxidant enzyme expression. Therefore, we conclude that miR-150 transfection into ASCs has the potential to induce the release of secretory materials with enhanced antifibrotic, proliferative, and antioxidant properties., Regenerative medicine: Training stem cells to fix liver fibrosis A mixture of molecules produced by genetically modified stem cells could help repair the damage associated with liver fibrosis. Fat-derived adipose stem cells (ASCs) secrete proteins and nucleic acids that can facilitate tissue regeneration, but the natural mixture of molecules secreted (the ‘secretome’) is insufficient to reverse advanced fibrosis. Researchers led by Say-June Kim of the Catholic University of Korea, Seoul, South Korea, have boosted the potency of this cell-derived treatment by engineering ASCs to produce an RNA called miR-150. This RNA inhibits biological processes that drive fibrosis. Experiments in cultured cells and a mouse model of fibrosis confirmed that miR-150 consistently improved the ASC secretome’s capacity to control liver fibrosis and minimize systemic inflammatory responses. This approach could thus offer a safe strategy for promoting tissue regeneration and preventing liver failure.

Background Although methyl-tertiary butyl ether (MTBE) is the only clinical topical agent for gallstone dissolution, its use is limited by its side effects mostly arising from a relatively low boiling point (55 °C). In this study, we developed the gallstone-dissolving compound containing an aromatic moiety, named 2-methoxy-6-methylpyridine (MMP) with higher boiling point (156 °C), and compared its effectiveness and toxicities with MTBE. Methods The dissolubility of MTBE and MMP in vitro was determined by placing human gallstones in glass containers with either solvent and, then, measuring their dry weights. Their dissolubility in vivo was determined by comparing the weights of solvent-treated gallstones and control (dimethyl sulfoxide)-treated gallstones, after directly injecting each solvent into the gallbladder in hamster models with cholesterol and pigmented gallstones. Results In the in vitro dissolution test, MMP demonstrated statistically higher dissolubility than did MTBE for cholesterol and pigmented gallstones (88.2% vs. 65.7%, 50.8% vs. 29.0%, respectively; P

Background Secretome refers to the total set of molecules secreted or surface-shed by stem cells. The limitations of stem cell research have led numerous investigators to turn their attention to the use of secretome instead of stem cells. In this study, we intended to reinforce antifibrotic properties of the secretome released from adipose-derived stem cells (ASCs) transfected with miR-214. Methods We generated miR-214-transfected ASCs, and extracted the secretome (miR214-secretome) from conditioned media of the transfected ASCs through a series of ultrafiltrations. Subsequently, we intravenously injected the miR-214-secretome into mice with liver fibrosis, and determined the effects of miR-214-secretome on liver fibrosis. Results Compared with that by naïve secretome, liver fibrosis was ameliorated by intravenous infusion of miR-214-secretome into mice with liver fibrosis, which was demonstrated by significantly lower expression of fibrosis-related markers (alpha-smooth muscle actin, transforming growth factor-β, and metalloproteinases-2) in the livers as well as lower fibrotic scores in the special stained livers compared with naïve secretome. The infusion of miR-214-secretome also led to lesser local and systemic inflammation, higher expression of an antioxidant enzyme (superoxide dismutase), and higher liver proliferative and synthetic function. Conclusion MicroRNA-214 transfection stimulates ASCs to release the secretome with higher antifibrotic and anti-inflammatory properties. miR-214-secretome is thus expected to be one of the prominent ways of overcoming liver fibrosis, if further studies consistently validate its safety and efficiency., Graphical Abstract

// Sang Chul Lee 1 , Ok-Hee Kim 1 , Sang Kuon Lee 1 , Say-June Kim 1 1 Department of Surgery, Daejeon St. Mary’s Hospital, College of Medicine, The Catholic University of Korea, Daejeon, Republic of Korea Correspondence to: Say-June Kim, e-mail: sejoonkim@hanmail.net Keywords: IWR-1, survivin, epithelial mesenchymal transition (EMT), colorectal cancer, wnt/β-catenin signaling Received: January 07, 2015 Accepted: September 04, 2015 Published: September 16, 2015 ABSTRACT Aberrant activation of Wnt/β-catenin signaling is frequently observed in patients with colorectal cancer (CRC) and is considered a major determinant of CRC pathogenesis. CRC pathogenesis is particularly accompanied by epithelial-mesenchymal transition (EMT) and survivin expression. Here, we investigated the potential and mechanism of a novel Wnt/β-catenin inhibitor IWR-1 to suppress tumor metastasis in relation with EMT and survivin expression. We first determined the EMT reversal effects of IWR-1 in in vitro (HCT116 and HT29 cells) and ex vivo (specimens of CRC patients) CRC models. It was shown that IWR-1 inhibited cell proliferation and EMT even in the presence of TNF-α-induced cancer cell stimulation. IWR-1 also significantly suppressed cell migration, invasion, and matrix metalloproteinase activities of CRC cell lines. Furthermore, we showed the evidence that IWR-1 provides EMT reversal effects by directly suppressing survivin expression by the followings: 1) IWR-1 could not completely inhibit EMT in survivin-overexpressing HCT116 cells, 2) EMT reversal effects of IWR-1 were more pronounced in survivin-suppressed cells, and 3) Survivin promoter assay directly identified the survivin promoter region responsible for inhibition of survivin transcription by IWR-1. Taken altogether, our results demonstrate that IWR-1 has the potential to suppress tumor metastasis by inhibiting Wnt/β-catenin pathway as well as survivin expression. Therefore, IWR-1 could be considered for future clinical use as a therapeutic agent to treat CRC.

It is challenging to overcome the low response rate of everolimus in the treatment of patients with hepatocellular carcinoma (HCC). To overcome this challenge, we combined everolimus with Ku0063794, the inhibitor of mTORC1 and mTORC2, to achieve higher anticancer effects. However, the precise mechanism for the synergistic effects is not clearly understood yet. To achieve this aim, the miRNAs were selected that showed the most significant variation in expression according to the mono- and combination therapy of everolimus and Ku0063794. Subsequently, the roles of specific miRNAs were determined in the processes of the treatment modalities. Compared to individual monotherapies, the combination therapy significantly reduced viability, increased apoptosis, and reduced autophagy in HepG2 cells. The combination therapy led to significantly lower expression of miR-4790-3p and higher expression of zinc finger protein225 (ZNF225)—the predicted target of miR-4790-3p. The functional study of miR-4790-3p and ZNF225 revealed that regarding autophagy, miR-4790-3p promoted it, while ZNF225 inhibited it. In addition, regarding apoptosis, miR-4790-3p inhibited it, while ZNF225 promoted it. It was also found that HCC tissues were characterized by higher expression of miR-4790-3p and lower expression of ZNF225, HCC tissues were also characterized by higher autophagic flux. We, thus, conclude that the potentiated anticancer effect of the everolimus and Ku0063794 combination therapy is strongly associated with reduced autophagy resulting from diminished expression of miR-4790-3p, as well as higher expression of ZNF225.

Purpose Survivin is a typical antiapoptotic protein. It is copiously expressed during human fetal development but is infrequently present in adult tissues. In this experiment, we researched the treatment effect of the secretome that adipose-derived stem cells (ASCs) transfected with survivin. Methods First of all, we generated survivin-overexpressing ASCs transfected with a plasmid comprising a gene encoding survivin. The secreted substances released from survivin-overexpressing ASCs (survivin-secretome) were collected, and were determined their in vitro and in vivo therapeutic potential, especially in the model of liver impairment. Results In vitro, the survivin-secretome significantly increased cell viability and promoted the expression of proliferation-related markers (proliferating cell nuclear antigen [PCNA], phospho-signal transducer and activator of transcription 3 (p-STAT3), hepatocyte growth factor [HGF], vascular endothelial growth factor [VEGF]) and anti-apoptosis-related markers (myeloid cell leukemia-1 [Mcl-1] and survivin) (P < 0.05). In vivo using 70% hepatectomy mice, the survivin-secretome group exhibited the lowest serum levels of interleukin-6, tumor necrosis factor-α (P < 0.05). The serum levels of liver transaminases (alanine aminotransferase and aspartate aminotransferase) were also the lowest in the survivin-secretome group (P < 0.05). The survivin-secretome group also exhibited the highest liver regeneration on the 7th day after 70% partial hepatectomy (P < 0.05). In the subsequent liver specimen analysis, the specimens of survivin-secretome exhibited the highest expression of p-STAT3, HGF, VEGF, PCNA, and Mcl-1 and the lowest expression of bcl-2-like protein 4 (P < 0.05). Conclusion Taken together, secretome secreted by survivin-overexpressing ASCs could be an effective way to improve liver regeneration and repair for liver injury treatment.

The traditional manufacturing method used to produce goods from Hizikia fusiforme, utilizes extraction steps with hot water. The byproduct (of hot water extraction) is rich in polysaccharide and is considered a waste. To evaluate the osteogenic effects of the byproduct of H. fusiforme (HFB), osteogenic cells and animal models were used to test it effects on osteogenesis. The HFB-treated mouse myoblast C2C12 cells exhibited significant dose dependently elevated alkaline phosphatase (ALP) activity and slightly increased bone morphogenetic protein-2 (BMP-2). HFB also suppressed the formation of tartrate-resistant acid phosphatase (TRAP) activity and TRAP staining in the bone marrow-derived macrophages (BMM) cells that had been stimulated with the receptor activator of the nuclear factor kB ligand/macrophage colony-stimulating factor kB ligand. In addition, HFB also increased the phosphorylation of extracellular signal-regulated protein kinase (p-ERK) level. Finally, osteogenic effects of HFB were clearly confirmed in the three in vivo models: zebrafish, ovariectomized mice, and mouse calvarial bones. HFB accelerated the rate of skeletal development in zebrafish and prevented much of the mouse femoral bone density loss of ovariectomized mice. Moreover, HFB enhanced woven bone formation over the periosteum of mouse calvarial bones. Our result showed that HFB functions as a bone resorption inhibitor as well as an activator of bone formation in vivo and in osteogenic in vitro cell systems.

Onion-like Pt-terminated Pt–Cu bimetallic nano-sized electrocatalysts (Pt/Cu/Pt/C) were synthesized by using an electroless deposition method. The synthesized Pt/Cu/Pt/C consisted of a Pt-enriched shell, a sandwiched Pt–Cu alloy layer, and a Pt core. The Pt/Cu/Pt/C showed higher electrocatalytic activity toward oxygen reduction reaction in half-cell test than that of commercial Pt/C due to an electronic structure change in the Pt-enriched shell, resulting from the sandwiched Pt–Cu alloy layer underneath. The stability of the Pt/Cu/Pt/C was examined by using both half-cell and single-cell degradation tests. In both tests, the Pt/Cu/Pt/C exhibited stronger resistance to catalyst degradation than that of the commercial Pt/C. It is notable that cell performance with the Pt/Cu/Pt/C was fully recovered by N2 purging after single-cell degradation testing, indicating there was no permanent damage to the electrocatalyst during the test. It is suggested that thermodynamically-stable structure of the Pt/Cu/Pt/C contributed to the improved stability.

Background: The stem cell-derived secretome has received considerable attention as an alternative to stem cells for therapeutic applications. However, establishing optimal culture conditions is key to obtaining appropriate secretome contents. Here, the optimal culturing environment for achieving a high-efficiency secretome was determined via hypoxic preconditioning of human adipose-derived stem cells (ASC). Methods: Normoxic conditioned media (NCM) and hypoxic conditioned media (HCM) were obtained after culturing human ASCs under normoxia (20% O2) or hypoxia (1% O2), respectively. Subsequently, both normal and thioacetamide-induced hepatotoxic hepatocytes were treated with NCM or HCM. In addition, partially hepatectomized mice were infused with control saline, NCM, and HCM. The effects on liver regeneration and serum transaminases levels were then compared. Results: Hypoxic preconditioning significantly increased mRNA expression of proinflammatory cytokines (interleukin-6 and tumor necrosis factor-) and growth factors (hepatocyte growth factor and vascular endothelial growth factor). In both normal and thioacetamide-induced hepatotoxic hepatocyte (alpha mouse liver 12 [AML12]) cell lines, HCM treatment resulted in the highest cell viability (122% and 95%, respectively), followed by NCM (111% and 78%, respectively). In addition, intravenous administration of HCM to partially hepatectomized mice resulted in substantially enhanced liver regeneration compared with the NCM group (P

Electrochemical catalysts with a core-shell structure have received much attention because of their enhanced efficiency and activity. Among them, those with a CuPd alloy core exhibit better activity than the ones with a single metal Pd core, which is known to be an excellent core-material. However, the superior performance of previously reported Pt catalysts with CuPd core has only been observed in half-cells, and was not reflected or even expanded to single-cells. We report catalysts having a Matryoshka-like structure with a Pt outer-layer, Cu interlayer, and Pd core for oxygen reduction reaction. This catalyst has 3.4 times higher Pt mass activity than the commercial Pt/C in half-cells, and also performs better in single-cells at only 0.056 mgPt cm−2. Particularly, the stability of this catalyst satisfies the 2020 DOE target, and electrochemical surface area loss during the stability test is only 40 % for this catalyst, while that of Pt/C is 80 %.

This paper aims to validate if intrapancreatic injection of penicillin G can enhance hardness and suture holding capacity (SHC) of the pancreas through prompting the fibrosis process. Soft pancreatic texture is constantly mentioned as one of the most contributory predictors of postoperative pancreatic fistula (POPF). Soft pancreas has poor SHC and higher incidence of parenchymal tearing, frequently leading to POPF. From a library of 114 antibiotic compounds, we identified that penicillin G substantially enhanced pancreatic hardness and SHC in experimental mice. Specifically, we injected penicillin G directly into the pancreas. On determined dates, we measured the pancreatic hardness and SHC, respectively, and performed molecular and histological examinations for estimation of the degree of fibrosis. The intrapancreatic injection of penicillin G activated human pancreatic stellate cells (HPSCs) to produce various fibrotic materials such as transforming growth factor-&beta, 1 (TGF-&beta, 1) and metalloproteinases-2. The pancreatic hardness and SHC were increased to the maximum at the second day after injection and then it gradually subsided demonstrating its reversibility. Pretreatment of mice with SB431542, an inhibitor of the TGF-&beta, 1 receptor, before injecting penicillin G intrapancreatically, significantly abrogated the increase of both pancreatic hardness and SHC caused by penicillin G. This suggested that penicillin G promotes pancreatic fibrosis through the TGF-&beta, 1 signaling pathway. Intrapancreatic injection of penicillin G promotes pancreatic hardness and SHC by enhancing pancreatic fibrosis. We thus think that penicillin G could be utilized to prevent and minimize POPF, after validating its actual effectiveness and safety by further studies.

Purpose Visfatin is a key cytokine released from the pe ripheral blood mononuclear cells (PBMCs) as well as adipose tissue, and it is involved in immune response as well as inflammation. In this study, we investigated whether the serum visfatin level could be a prognostic factor for predicting the severity of inflammation in patients with acute cholecystitis. Methods We examined the blood samples and gallbladder specimens from patients who underwent laparoscopic cholecystectomy for either acute (n = 18) or chronic cholecystitis (n = 18). We determined the visfatin levels of these samples using various procedures such as real-time polymerase chain reaction, enzyme-linked immunosorbent assay, western blotting, and immunohistochemistry. Results The patients with acute cholecystitis exhibited higher mRNA expression of visfatin in PBMCs, higher serum levels of visfatin, and increased protein expression of visfatin in the gallbladder specimens than in patients with chronic cholecystitis. In the in vitro model of acute cholecystitis, the mRNA expression of visfatin showed the fastest increase among the other pro-inflammatory mediators studied, including interleukin (IL)-10, tumor necrosis factor-α, IL-6, intracellular adhesion molecule-1, and ascular cell adhesion molecule-1. Inhibition of visfatin using siRNA abrogated the inhibitory effects of lipopolysaccharide (LPS) on the expression of ABCG1 in GBECs, suggesting that visfatin is significantly involved in the LPS-driven suppression of ABCG1. Conclusion Taken together, we concluded that visfatin is a pro-inflammatory mediators that is upregulated during acute cholecystitis and is expected to be increased within a short time after inflammation. Therefore, measuring the serum level of visfatin would be helpful in predicting the inflammatory severity in the patients with acute cholecystitis.

Beyond a traditional view that metal nanoparticles formed upon electrochemical reaction are inactive against lithium, recently their electrochemical participations are manifested and elucidated as catalytic and interfacial effects. Here, ruthenium metal composed of ≈5 nm nanoparticles is prepared and the pure ruthenium as a lithium-ion battery anode for complete understanding on anomalous lithium storage reaction mechanism is designed. In particular, the pure metal electrode is intended for eliminating the electrochemical reaction-derived Li2 O phase accompanied by catalytic Li2 O decomposition and the interfacial lithium storage at Ru/Li2 O phase boundary, and thereby focusing on the ruthenium itself in exploring its electrochemical reactivity. Intriguingly, unusual lithium storage not involving redox reactions with electron transfer but leading to lattice expansion is identified in the ruthenium electrode. Size-dependent charge redistribution at surface enables additional lithium adsorption to occur on the inactive but more environmentally sensitive nanoparticles, providing innovative insight into dynamic electrode environments in rechargeable lithium chemistry.

A carbon-supported Pt-RuS2 nanocomposite (Pt-RuS2/C) that contained extremely small amount of Pt compared with commercial Pt/C was prepared by the deposition of Pt nanoparticles (NPs) onto carbon-supported RuS2 NPs. This Pt-RuS2/C NP was demonstrated to be an electrocatalyst for hydrogen oxidation reaction catalyst for polymer electrolyte membrane fuel cells using membrane electrode assembly in a single-cell performance test and CO-stripping measurements. The results of structural analysis on prepared nanocomposite showed highly dispersed Pt (ca. 2.5 nm in diameter) and RuS2 (ca. 5.5 nm in diameter) NPs on carbon particles. Pt existed in an unalloyed phase in Pt-RuS2/C, and RuS2 NPs were in physical contact with Pt NPs. Although the amount of Pt in the Pt-RuS2/C NP was only 21.7 % of commercial Pt/C, the Pt-RuS2/C exhibited comparable single-cell performance to commercial Pt/C as an anode electrocatalyst, owing to the promoting effect of RuS2 on the reactivity of Pt.

Core-shell structure nanoparticles have been the subject of many studies over the past few years and continue to be studied as electrocatalysts for fuel cells. Therefore, many excellent core-shell catalysts have been fabricated, but few studies have reported the real application of these catalysts in a practical device actual application. In this paper, we demonstrate the use of platinum (Pt)-exoskeleton structure nanoparticles as cathode catalysts with high stability and remarkable Pt mass activity and report the outstanding performance of these materials when used in membrane-electrode assemblies (MEAs) within a polymer electrolyte membrane fuel cell. The stability and degradation characteristics of these materials were also investigated in single cells in an accelerated degradation test using load cycling, which is similar to the drive cycle of a polymer electrolyte membrane fuel cell used in vehicles. The MEAs with Pt-exoskeleton structure catalysts showed enhanced performance throughout the single cell test and exhibited improved degradation ability that differed from that of a commercial Pt/C catalyst.

Ion transport is an important issue in electrochemical-based energy conversion and storage devices. Ion transport at the interface of the electrode and electrolyte is critical for performance. However, there is little understanding of the interface phenomena based on ion transport properties. Here, the proton transport behavior in a Nafion membrane (electrolyte) and that of an ionomer in the catalyst layer (electrode/electrolyte interface) was investigated simultaneously by electrochemical impedance spectroscopy. Our study indicates that the proton transport behavior in the catalyst layer is different from that in membrane. To elucidate the interface phenomena, we analyzed the Nafion electrolyte and proton behavior by molecular dynamics (MD). On the basis of the MD results, we modified the catalyst with a hybrid of inorganic Pt catalyst and organic 3-mercaptopropionic acid to promote a positive interfacial reaction between the electrolyte and electrode, which resulted in improved proton transport and perf...

Core–shell structured Au–PtPd/C and Au–Pt/C nanoparticles (NPs) were prepared using a successive reduction process on carbon supported Au with PtPd and Pt particles. Structural analyses of the core–shell NPs revealed uniformly distributed fine particles (

Background A hypoxic-preconditioned secretome from stem cells reportedly promotes the functional and regenerative capacity of the liver more effectively than a control secretome. However, the optimum oxygen partial pressure (pO2) in the cell culture system that maximizes the therapeutic potential of the secretome has not yet been determined. Methods We first determined the cellular alterations in adipose tissue-derived stem cells (ASCs) cultured under different pO2 (21%, 10%, 5%, and 1%). Subsequently, partially hepatectomized mice were injected with the secretome of ASCs cultured under different pO2, and then sera and liver specimens were obtained for analyses. Results Of all AML12 cells cultured under different pO2, the AML12 cells cultured under 1% pO2 showed the highest mRNA expression of proliferation-associated markers (IL-6, HGF, and VEGF). In the cell proliferation assay, the AML12 cells cultured with the secretome of 1% pO2 showed the highest cell proliferation, followed by the cells cultured with the secretome of 21%, 10%, and 5% pO2, in that order. When injected into the partially hepatectomized mice, the 1% pO2 secretome most significantly increased the number of Ki67-positive cells, reduced serum levels of proinflammatory mediators (IL-6 and TNF-α), and reduced serum levels of liver transaminases. In addition, analysis of the liver specimens indicated that injection with the 1% pO2 secretome maximized the expression of the intermediate molecules of the PIP3/Akt and IL-6/STAT3 signaling pathways, all of which are known to promote liver regeneration. Conclusions The data of this study suggest that the secretome of ASCs cultured under 1% pO2 has the highest liver reparative and regenerative potential of all the secretomes tested here. Electronic supplementary material The online version of this article (doi:10.1186/s13287-017-0635-x) contains supplementary material, which is available to authorized users.