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Charcot-Marie-Tooth (CMT) is a group of inherited diseases clinically and genetically heterogenous, characterised by length dependent degeneration of axons of the peripheral nervous system. A missense mutation (p.R158H) in the pyruvate dehydrogenase kinase 3 gene (PDK3) has been identified as the genetic cause for an X-linked form of CMT (CMTX6) in two unrelated families. PDK3 is one of four PDK isoenzymes that regulate the activity of the pyruvate dehydrogenase complex (PDC). The balance between kinases (PDKs) and phosphatases (PDPs) determines the extend of oxidative decarboxylation of pyruvate to generate acetyl CoA, critically linking glycolysis and the energy producing Krebs cycle. We had shown the p.R158H mutation causes hyperactivity of PDK3 and CMTX6 fibroblasts show hyperphosphorylation of PDC, leading to reduced PDC activity and ATP production. In this manuscript we have generated induced pluripotent stem cells (iPSCs) by re-programming CMTX6 fibroblasts (iPSCCMTX6). We also have engineered an isogenic control (iPSCisogenic) and demonstrated that genetic correction of the p.R158H mutation reverses the CMTX6 phenotype. Patient-derived motor neurons (MNCMTX6) show increased phosphorylation of the PDC, energy metabolism defects and mitochondrial abnormalities, including reduced velocity of trafficking mitochondria in the affected axons. Treatment of the MNCMTX6 with a PDK inhibitor reverses PDC hyperphosphorylation and the associated functional deficits founds in the patient motor neurons, demonstrating that the MNCMTX6 and MNisogenic motor neurons provide an excellent neuronal system for compound screening approaches to identify drugs for the treatment of CMTX6.

The herb dwarf lilyturf tuber (Maidong, Ophiopogonis Radix) is widely used in Chinese traditional medicine to manage diabetes and its complications. However, the role of Maidong polysaccharide extract (MPE) in pancreatic β-cell function is unclear. Here, we investigated whether MPE protects β-cell function and studied the underlying mechanisms. We treated db/db and high-fat diet (HFD)-induced obese mice with 800 or 400 mg/kg MPE or water for 4 weeks, followed by an oral glucose tolerance test. Pancreas and blood were collected for molecular analyses, and clonal MIN6 β-cells and primary islets from HFD-induced obese mice and normal chow diet–fed mice were used in additional analyses. In vivo, MPE both increased insulin secretion and reduced blood glucose in the db/db mice but increased only insulin secretion in the HFD-induced obese mice. MPE substantially increased the β-cell area in both models (3-fold and 2-fold, p < 0.01, for db/db and HFD mice, respectively). We observed reduced nuclear translocation of the p65 subunit of NF-κB in islets of MPE-treated db/db mice, coinciding with enhanced glucose-stimulated insulin secretion (GSIS). In vitro, MPE potentiated GSIS and decreased interleukin 1β (IL-1β) secretion in MIN6 β-cells. Incubation of MIN6 cells with tumor necrosis factor α (TNFα), interferon-γ, and IL-1β amplified IL-1β secretion and inhibited GSIS. These effects were partially reversed with MPE or the IκB kinase β inhibitor PS1145, coinciding with reduced activation of p65 and p-IκB in the NF-κB pathway. We conclude that MPE may have potential for therapeutic development for β-cell protection.

A major hurdle in stem cell therapy is the tumorigenic risk of residual undifferentiated stem cells. This report describes the design and evaluation of synthetic hybrid molecules that efficiently reduce the number of human induced pluripotent stem cells (hiPSCs) in cell mixtures. The design takes advantage of Kyoto probe 1 (KP-1), a fluorescent chemical probe for hiPSCs, and clinically used anticancer drugs. Among the KP-1-drug conjugates we synthesized, we found an exceptionally selective, chemically tractable molecule that induced the death of hiPSCs. Mechanistic analysis suggested that the high selectivity originates from the synergistic combination of transporter-mediated efflux and the cytotoxicity mode of action. The present study offers a chemical and mechanistic rationale for designing selective, safe, and simple reagents for the preparation of non-tumorigenic clinical samples.

Pharmacophore-focused chemical libraries are continuously being created in drug discovery programs, yet screening assays to maximize the usage of such libraries are not fully explored. Here, we report a chemical proteomics approach to reutilizing a focused chemical library of 1,800 indole-containing molecules for discovering uncharacterized ligand-protein pairs. Gel-based protein profiling of the library using a photo-affinity indole probe 1 enabled us to find new ligands for glyoxalase 1 (Glo1), an enzyme involved in the detoxification of methylglyoxal. Structure optimization of the ligands yielded an inhibitor for Glo1 (9). Molecule 9 increased the cellular methylglyoxal levels in human cells and suppressed the osteoclast formation of mouse bone marrow-derived macrophages. X-ray structure analyses revealed that the molecule lies at a site abutting the substrate binding site, which is consistent with the enzyme kinetic profile of 9. Overall, this study exemplifies how chemical proteomics can be used to exploit existing focused chemical libraries.

Pinopode and Mucin 1 (MUC1) have both been proposed as morphological and molecular markers of endometrial receptivity for implantation. However, their spatial relationship in luminal epithelium and its association with reproductive failure are still unclear. This was a prospective cohort study conducted at a university assisted reproductive unit including 9 receptive control women, 18 infertile women, and 22 women with recurrent implantation failure (RIF) and 22 women with recurrent miscarriage (RM). Endometrial tissues were obtained at 7 days after luteinizing hormone surge during implantation window. Luminal epithelium was examined by scanning electron microscopy (SEM). MUC1 localization in luminal epithelium was detected by scanning immunoelectron microscopy (SIM) and compared by modified double immunofluorescence (mIF) staining without antigen retrieval. SEM did not show any significant difference in percentage of secretory cells, any stage of pinopodes, and ciliated cells between control, infertility, RIF and RM groups. SIM identified MUC1 was mainly localized on surface of ciliated cells and at the bottom of cilia, not secretory cells and pinopodes, and its specific localization was validated by mIF staining. MUC1 expression in ciliated cells in control women was significantly higher than those women with reproductive failure, but there was no significant difference between RIF and RM. In conclusion, MUC1 is mainly expressed in ciliated cells, not secretory cells and pinopodes, of the endometrial luminal epithelium during implantation window. The specific expression of MUC1 in the ciliated cells in receptive control women is higher than that of women with reproductive failure during implantation window.

Cervical cancer (CC) is one of the most common female malignancies in the world. Although paclitaxel (PTX) is a critical chemotherapy agent for the treatment of CC, its treatment outcome is limited by the development of drug resistance. The present study aims to define the role of long non-coding RNA (lncRNA) LINC00511 in the progression of CC with the involvement of cell proliferation, apoptosis and resistance to PTX in Hela/PTX cells. CC and adjacent normal tissue samples were collected from 84 patients with CC, and used to determine LINC0051 expression. PTX-resistant Hela/PTX cell line was constructed, in which LINC0051 was overexpressed or silenced to further investigate the effect of LINC00511 on PTX-resistant Hela/PTX cell viability, proliferation, migration, invasion, cell cycle, apoptosis and resistance of CC cells to PTX. The expression of Bcl-2, Bax, cleaved-caspase-3, matrix metalloproteinase (MMP)-2, MMP-9, multidrug resistance protein 1 (MRP1) and P-glycoprotein (P-GP) was also assessed. High-expression of LINC00511 was found in CC with its close association with the tumor stage, tumor size and lymph node metastasis. After silencing LINC00511 expression, the expression of MRP1, P-GP, Bcl-2, MMP-2 and MMP-9 was decreased, while Bax and cleaved-caspase-3 increased with more CC cells arrested at G1 phase. Furthermore, silencing of LINC00511 could suppress cell resistance to PTX, cell viability, cell proliferation, migration and invasion yet promoted cell apoptosis in PTX-resistant Hela/PTX cells. Collectively, our findings demonstrate that silencing of LINC00511 could inhibit CC cell resistance to PTX, cell proliferation, migration and invasion, and promote cell apoptosis in CC. Silencing of LINC00511 provides a novel therapeutic target for CC.

Shell is aquatic product processing industry waste, shrimp, crab and shellfish contain heavy metal, cause this kind of waste water deposits, the pollution caused by the Marine area, but the shell and shrimp shell contains rich off acetyl chitosan, chitosan degradation into shell oligosaccharides have many function effect, from the perspective of environmental protection is to deal with some of the pollution, and the preparation of the beneficial shell oligosaccharides. This paper introduces the extraction of chitosan from shrimp shells and the preparation of sunscreen by using physical degradation method to extract chitosan oligosaccharide from chitosan. In this paper, natural chito-oligosaccharides were extracted from shellfish waste and used as ingredients to make natural sunscreen, which was an exploration of chito-oligosaccharides in the field of daily use in fine chemical industry.

This report describes the design and evaluation of phosphorylated 7-ethyl-10-hydroxycamptothecin (SN38-P), which selectively eliminates tumor-forming proliferative stem cells, including human induced pluripotent stem cells (hiPSCs) and neural stem cells, from iPSC-derived neural cell mixtures. Results of the present study demonstrate that simple phosphorylation of an anticancer drug can provide a safe, cost-effective, and chemically-defined tool for decontaminating hiPSC-derived neuron.

Cell replacement therapy for diabetes mellitus requires cost-effective generation of high-quality, insulin-producing, pancreatic β cells from pluripotent stem cells. Development of this technique has been hampered by a lack of knowledge of the molecular mechanisms underlying β-cell differentiation. The present study identified reserpine and tetrabenazine (TBZ), both vesicular monoamine transporter 2 (VMAT2) inhibitors, as promoters of late-stage differentiation of Pdx1-positive pancreatic progenitor cells into Neurog3 (referred to henceforth as Ngn3)-positive endocrine precursors. VMAT2-controlled monoamines, such as dopamine, histamine and serotonin, negatively regulated β-cell differentiation. Reserpine or TBZ acted additively with dibutyryl adenosine 3',5'-cyclic AMP, a cell-permeable cAMP analog, to potentiate differentiation of embryonic stem (ES) cells into β cells that exhibited glucose-stimulated insulin secretion. When ES cell-derived β cells were transplanted into AKITA diabetic mice, the cells reversed hyperglycemia. Our protocol provides a basis for the understanding of β-cell differentiation and its application to a cost-effective production of functional β cells for cell therapy.

Thermal analyses of epoxidized soybean oil (ESO) were conducted and showed that it was stable up to temperatures as high as 240–260°C in air-free environment. The solubility and transport characteristics of ESO in poly(vinylchloride) (PVC) were also investigated under various conditions. The absorption study showed that the resin had a void volume of ∼0.3 cm3/g. Furthermore, ESO was found to be sufficiently soluble in the PVC matrix to function as an effective plasticizer, with equilibrium solubility of 72 g/100 g PVC at 80°C and 163 g/100 g PVC at 120°C. The absorption of ESO in PVC grains was a three step process comprising “induction,” “swelling,” and “saturation” periods. Torque rheometer studies showed that higher mixer temperature and/or speed facilitated uptake of plasticizer in PVC and ultimate fusion. Migration studies of plasticized and stabilized PVC compositions showed no change in mass at 40°C, but increasingly greater mass loss as the temperature was raised up to 120°C. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers

The efficacy of epoxidized soybean oil (ESO), tri(2-ethylhexyl) trimellitate, and mixtures thereof as plasticizers for poly(vinylchloride) has been studied. At 80°C, the trimellitate was slower to absorb in this polymer than ESO and was also less soluble, but the former exhibited higher solubility at 120°C. Plasticization efficiencies of stabilized polymeric compositions were similar with ESO and the trimellitate (despite their very different molecular weights). The trimellitate yielded greater mass loss during heat aging of the plasticized compositions, but substituting even minor amounts of it with ESO decreased mass loss synergistically. The trimellitate also resulted in more of an increase in hardness than ESO over time at elevated temperatures, but when aged at 120°C, mixtures of the two surprisingly had more deleterious effects. Thus, although ESO can replace part or all of trimellitates in plasticized PVC, using it as sole plasticizer would be preferable when heat aging performance is a requirement. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41966.

One of the current obstacles to stem cell therapy is the tumorigenic potential of residual undifferentiated stem cells. The present study reports rediscovery of a synthetic derivative of okadaic acid, a marine polyether toxin, as a reagent that selectively induces the death of human pluripotent stem cells. Cell-based screening of 333 cytotoxic compounds identified methyl 27-deoxy-27-oxookadaate (molecule 1) as a substrate of two ATP-binding cassette (ABC) transporters, ABCB1 (MDR1) and ABCG2 (BCRP), whose expression is repressed in human embryonic stem cells and induced pluripotent stem cells. The results demonstrate that selective elimination of human pluripotent stem cells can be achieved by designing cytotoxic small molecules with appropriate ABC-transporter selectivity.