Improved Tribological Performance of MOF@MXene/PI under High Temperature.

High-temperature-resistant and self-lubricating polymer composites with long life and high reliability are increasingly indispensable in the aerospace field. Herein, ZIF-67 grown on the MXene lamella was successfully prepared, and ZIF-67@MXene/PI composites with a regular layered structure were obtained by a hot-pressing three-dimensional network aerogel. It was revealed that incorporating ZIF-67@MXene into PI dramatically reduced the friction and abrasion with elevated temperatures. Largely, aerogel walls always paralleled the sliding direction by compressing, providing a significant antifriction effect. More notably, the presence of a vigorous tribofilm composed of a PI matrix and a diamond-type lattice MOF-modified MXene provided rolling and sliding interface friction under high temperatures, simultaneously. In addition, the uniform tribofilm with a thickness of about 200 nm can effectively avoid the direct contact of the friction pair during the sliding process. Hence, the combination of the constructed multiscale nanocomposites and nanostructured tribofilm with outstanding tribological performance endow the material potentially useful in reducing energy consumption, thus addressing the energy wastage problem caused by friction.

Human amniotic epithelial stem cell is a cell therapy candidate for preventing acute graft-versus-host disease.

Graft-versus-host disease (GVHD), an immunological disorder that arises from donor T cell activation through recognition of host alloantigens, is the major limitation in the application of allogeneic hematopoietic stem cell transplantation (allo-HSCT). Traditional immunosuppressive agents can relieve GVHD, but they induce serious side effects. It is highly required to explore alternative therapeutic strategy. Human amniotic epithelial stem cells (hAESCs) were recently considered as an ideal source for cell therapy with special immune regulatory property. In this study, we evaluated the therapeutic role of hAESCs in the treatment of GVHD, based on our previous developed cGMP-grade hAESCs product. Humanized mouse model of acute GVHD (aGVHD) was established by injection of huPBMCs via the tail vein. For prevention or treatment of aGVHD, hAESCs were injected to the mice on day -1 or on day 7 post-PBMC infusion, respectively. We showed that hAESCs infusion significantly alleviated the disease phenotype, increased the survival rate of aGVHD mice, and ameliorated pathological injuries in aGVHD target organs. We demonstrated that hAESCs directly induced CD4+ T cell polarization, in which Th1 and Th17 subsets were downregulated, and Treg subset was elevated. Correspondingly, the levels of a series of pro-inflammatory cytokines were reduced while the levels of the anti-inflammatory cytokines were upregulated in the presence of hAESCs. We found that hAESCs regulated CD4+ subset polarization in a paracrine mode, in which TGFß and PGE2 were selectively secreted to mediate Treg elevation and Th1/Th17 inhibition, respectively. In addition, transplanted hAESCs preserved the graft-versus-leukemia (GVL) effect by inhibiting leukemia cell growth. More intriguingly, hAESCs infusion in HSCT patients displayed potential anti-GVHD effect with no safety concerns and confirmed the immunoregulatory mechanisms in the preclinical study. We conclude that hAESCs infusion is a promising therapeutic strategy for post-HSCT GVHD without compromising the GVL effect. The clinical trial was registered at www.clinicaltrials.gov as #NCT03764228.

Repair of Retinal Degeneration by Human Amniotic Epithelial Stem Cell-Derived Photoreceptor-like Cells.

The loss of photoreceptors is a major event of retinal degeneration that accounts for most cases of untreatable blindness globally. To date, there are no efficient therapeutic approaches to treat this condition. In the present study, we aimed to investigate whether human amniotic epithelial stem cells (hAESCs) could serve as a novel seed cell source of photoreceptors for therapy. Here, a two-step treatment with combined Wnt, Nodal, and BMP inhibitors, followed by another cocktail of retinoic acid, taurine, and noggin induced photoreceptor-like cell differentiation of hAESCs. The differentiated cells demonstrated the morphology and signature marker expression of native photoreceptor cells and, intriguingly, bore very low levels of major histocompatibility complex (MHC) class II molecules and a high level of non-classical MHC class I molecule HLA-G. Importantly, subretinal transplantation of the hAESCs-derived PR-like cells leads to partial restoration of visual function and retinal structure in Royal College of Surgeon (RCS) rats, the classic preclinical model of retinal degeneration. Together, our results reveal hAESCs as a potential source of functional photoreceptor cells; the hAESCs-derived photoreceptor-like cells could be a promising cell-replacement candidate for therapy of retinal degeneration diseases.

SPION-mediated miR-141 promotes the differentiation of HuAESCs into dopaminergic neuron-like cells via suppressing lncRNA-HOTAIR.

In this study, a bioinformatics analysis and luciferase reporter assay revealed that microRNA-141 could silence the expression of lncRNA-HOTAIR by binding to specific sites on lncRNA-HOTAIR. We used superparamagnetic iron oxide nanoparticles (SPIONs) to mediate the high expression of microRNA-141 (SPIONs@miR-141) in human amniotic epithelial stem cells (HuAESCs), which was followed by the induction of the differentiation of HuAESCs into dopaminergic neuron-like cells (iDNLCs). qPCR, western blot, immunofluorescence staining and HPLC all suggested that SPION-mediated overexpression of miR-141 could promote an increased expression of brain-derived neurotrophic factor (BDNF), DAT and 5-TH in HuAESC-derived iDNLCs. The RIP and ChIP assay also showed that overexpression of miR-141 could significantly inhibit the recruitment and binding of lncRNA-HOTAIR to EZH2 on BDNF gene promoter. cDNA microarray analysis revealed that the expression levels of 190 genes were much higher in iDNLCs than in HuAESCs. Finally, a protein interaction network analysis and identification showed that in the iDNLC group with SPIONs@miR-141, factors that interact with BDNF, such as FGF8, SHH, NTRK3 and CREB1, all showed significantly higher expression levels compared with those in the SPIONs@miR-Mut. Therefore, this study confirmed that the highly efficient expression of microRNA-141 mediated by SPIONs could improve the efficiency of HuAESCs differentiation into dopaminergic neuron-like cells.

Therapeutic effect of human amniotic epithelial cells in murine models of Hashimoto's thyroiditis and Systemic lupus erythematosus.

BACKGROUND AIMS: The chronic inflammation of autoimmune diseases develops repetitive localized destruction or systemic disorders, represented by Hashimoto's thyroiditis (HT) and Systemic lupus erythematosus (SLE) respectively. Currently, there are no efficient ways to treat these autoimmune diseases. Therefore, it is critically important to explore new therapeutic strategies. The aim of this study was to investigate the therapeutic efficacy of human amniotic epithelial cells (hAECs) in murine models of HT and SLE. METHODS: Experimental autoimmune thyroiditis (EAT) was induced in female CBA/J mice by immunization with porcine thyroglobulin (pTg). hAECs were intravenously administered at different time points during the disease course. MRL-Faslpr mice, a strain with spontaneously occurring SLE, were intravenously administered hAECs when their sera were positive for both anti-nuclear antibodies (ANAs) and anti-double-stranded DNA (anti-dsDNA) antibodies. Two weeks after the last cell transplantation, blood and tissue samples were collected for histological examination and immune system analysis. RESULTS: hAECs prevented lymphocytes infiltration into the thyroid and improved the damage of thyroid follicular in EAT mice. Correspondingly, hAECs administration reduced anti-thyroglobulin antibodies (TGAb), anti-thyroid peroxidase antibodies (TPOAb) and thyroid stimulating hormone (TSH) levels. SLE mice injected with hAECs appeared negative for ANAs and anti-dsDNA antibodies and showed reduced immunoglobulin profiles. Mechanically, hAECs modulated the immune cells balance in EAT and SLE mice, by downregulating the ratios of Th17/Treg cells in both EAT and SLE mice and upregulating the proportion of B10 cells in EAT mice. This was confirmed by in vitro assay, in which hAECs inhibited the activation of EAT mice-derived splenocytes. Moreover, hAECs improved the cytokine environment in both EAT and SLE mice, by suppressing the levels of IL-17A and IFN-γ and enhancing TGF-ß. CONCLUSION: These results demonstrated the immunoregulatory effect of hAECs for inflammation inhibition and injury recovery in HT and SLE murine models. The current study may provide a novel therapeutic strategy for these autoimmune diseases in clinic.

Biological characterization of human amniotic epithelial cells in a serum-free system and their safety evaluation.

Human amniotic epithelial cells (hAECs), derived from the innermost layer of the term placenta closest to the fetus, have been shown to be potential seed cells for allogeneic cell therapy. Previous studies have shown a certain therapeutic effect of hAECs. However, no appropriate isolation and culture system for hAECs has been developed for clinical applications. In the present study, we established a serum-free protocol for hAEC isolation and cultivation, in which better cell growth was observed compared with that in a traditional culture system with serum. In addition to specific expression of cell surface markers (CD29, CD166 and CD90), characterization of the biological features of hAECs revealed expression of the pluripotent markers SSEA4, OCT4 and NANOG, which was greater than that in human mesenchymal stem cells, whereas very low levels of HLA-DR and HLA-DQ were detected, suggesting the weak immunogenicity of hAECs. Intriguingly, CD90+ hAECs were identified as a unique population with a powerful immunoregulatory capacity. In a systemic safety evaluation, intravenous administration of hAEC did not result in hemolytic, allergy, toxicity issues or, more importantly, tumorigenicity. Finally, the therapeutic effect of hAECs was demonstrated in mice with radiation-induced damage. The results revealed a novel function of hAECs in systemic injury recovery. Therefore, the current study provides an applicable and safe strategy for hAEC cell therapy administration in the clinical setting.

Amniotic fluid-derived stem cells mixed with platelet rich plasma for restoration of rat alveolar bone defect.

Stem cells isolated from the amniotic fluid have been shown as a promising candidate for cell therapy and tissue engineering. However, the experimental and preclinical applications of amniotic fluid-derived stem cells (AFSCs) in the very field of maxillofacial bone tissue engineering are still limited. In this study, rat AFSCs were successfully harvested and characterized in vitro. The rat AFSCs showed typical fibroblastoid morphology, stable proliferation activity and multi-differentiation potential. Flow-cytometry analysis demonstrated that these cells were positive for CD29, CD44, and CD90, while negative for hematopoietic markers such as CD34 and CD45. The regenerative performance of AFSCs-premixed with platelet rich plasma (PRP) gel in restoration of alveolar bone defect was further investigated using a modified rat maxillary alveolar defect model. Micro-computer tomography and histological examination showed a superior regenerative capacity of AFSCs-premixed with PRP gel at both 4 and 8 weeks after operation comparing with control groups. Moreover, the implanted AFSCs can survive in the defect site and directly participate in the bone tissue regeneration. Taken together, these results indicated the feasibility of an AFSCs-based alveolar bone tissue engineering strategy for alveolar defect restoration.

Characterization of a micro-roughened TiO2/ZrO2 coating: mechanical properties and HBMSC responses in vitro.

Previous studies have shown that using ZrO2 as a second phase to bioceramics can significantly increase the bonding strength of plasma-sprayed composite material. In the present study, micro-roughened titanium dioxide/zirconia (TiO2/ZrO2) (30 wt% ZrO2) coating and TiO2 coating were plasma-sprayed onto Ti plates. The micro-structural characteristics and mechanical properties of both coatings were investigated. Furthermore, the biological behavior and osteogenic differentiation of human bone marrow mesenchymal stem cells (HBMSCs) on both TiO2/ZrO2 and TiO2 coatings were compared. The results indicated that the shear bond strength and microhardness of TiO2/ZrO2 coating were statistically higher than those of TiO2 coating. Scanning electron microscope observation revealed that more irregularly shaped protuberances and denser pores were formed on the surface of TiO2/ZrO2 coating compared with those of TiO2 coating. Further comparative analysis of HBMSC proliferation and osteogenic differentiation on both coatings showed that significantly higher cellular alkaline phosphatase activity and expression levels of Runx2 and Osterix at day 10 after osteogenic culture were found on TiO2/ZrO2 coating compared with TiO2 coating, while no statistically significant difference in cell proliferation and extracellular calcium deposition was observed. The present study suggests that TiO2/ZrO2 coating may be favorable for dental implant applications.

Human amniotic epithelial cell feeder layers maintain human iPS cell pluripotency via inhibited endogenous microRNA-145 and increased Sox2 expression.

Currently, human induced pluripotent stem (iPS) cells were generated from patient or disease-specific sources and share the same key properties as embryonic stem cells. This makes them attractive for personalized medicine, drug screens or cellular therapy. Long-term cultivation and maintenance of normal iPS cells in an undifferentiated self-renewing state are a major challenge. Our previous studies have shown that human amniotic epithelial cells (HuAECs) could provide a good source of feeder cells for mouse and human embryonic stem cells, or spermatogonial stem cells, but the mechanism for this is unknown. Here, we examined the effect of endogenous microRNA-145 regulation on Sox2 expression in human iPS cells by HuAECs feeder cells regulation, and in turn on human iPS cells pluripotency. We found that human IPS cells transfected with a microRNA-145 mutant expressed Sox2 at high levels, allowing iPS to maintain a high level of AP activity in long-term culture and form teratomas in SCID mice. Expression of stem cell markers was increased in iPS transfected with the microRNA-145 mutant, compared with iPS was transfected with microRNA-145. Besides, the expression of Drosha proteins of the microRNA-processor complex, required for the generation of precursor pre-miRNA, was significantly increased in human iPS cells cultured on MEF but not on HuAECs. Taken together, these results suggest that endogenous Sox2 expression may be regulated by microRNA-145 in human iPS cells with HuAECs feeder cells, and Sox2 is a crucial component required for maintenance of them in an undifferentiated, proliferative state capable of self-renewal.

Synergistic Improvement of Dielectric and Thermal Conductivity Properties for Polymers Filled with Multifunctional Modified Nanowires.

Dielectric composites are widely used in power electronics, power systems, aerospace, and other fields due to their extremely high power density. However, if their energy density can be further increased, the application range will be greatly improved. Improving the dielectric constant of composites is one of the most effective ways to increase the energy density. In this study, a preparation method for copper calcium titanate nanowires (CCTO-NWs) with adjustable aspect ratio was investigated. Upon incorporation of these CCTO-NWs into the polymer matrix, the nanocomposites exhibit a significantly higher dielectric constant and a lower dielectric loss. In addition, a thin layer of Al2O3 with excellent thermal conductivity is coated on the surface of the CCTO-NWs to form a core-shell structure nanowire CCTO-NW@Al2O3. The introduction of the thermal conductive layer of Al2O3 not only creates a continuous heat transfer path within the dielectric composite, increasing the thermal conductivity of the composite from 0.11 W/(m·K) of pure HIPS to 1.12 W/(m·K), but also serves as a buffer layer between HIPS and CCTO-NWs, effectively alleviating the electric field distortion caused by the large difference in the dielectric constant between them, thereby optimizing the dielectric properties of the composite and reducing the dielectric permeability threshold from 30 to 20 vol %. This work provides an effective strategy for synergistically improving the dielectric constant and thermal conductivity of dielectric composites while also taking into account the good flexibility of polymer/ceramic nanocomposites.

Human ovarian cancer stem-like cells can be efficiently killed by γδ T lymphocytes.

Ovarian cancer comprises a small population of cancer stem cells (CSCs) that are responsible for tumor maintenance and resistant to cancer therapies, it would be desirable to develop a therapy that could selectively target ovarian CSCs. Recently, cellular immune-based therapies have improved the prognosis of cancer patients clinically. In this study, we isolated a subset of ovarian cancer sphere cells that possess CSC properties and explored the cell cytotoxicity of γδ T cells to ovarian cancer sphere cells using a transwell cocultured cell system. The proliferation rate of the cancer sphere cells decreased to 40% after cocultured with γδ T cells. The γδ T cells increased the sensitivity of SK-OV-3 sphere cells to chemotherapeutic drugs. After the treatment of γδ T cells, the expression of stem cell marker genes decreased in sphere cells, while the expression of HLA-DR antigen on tumor cells was increased in a time-dependent manner. Further, γδ T cells induced G2/M phase cell cycle arrest and subsequent apoptosis in SK-OV-3 sphere cells. Xenograft mouse models demonstrated that γδ T cells dramatically reduced the tumor burden. Notably, the level of IL-17 production significantly increased after cocultured with γδ T cells. We conclude that γδ T cells may efficiently kill ovarian CSCs through IL-17 production and represent a promising immunotherapy for ovarian cancer.

CD44+/CD105+ human amniotic fluid mesenchymal stem cells survive and proliferate in the ovary long-term in a mouse model of chemotherapy-induced premature ovarian failure.

OBJECTIVES: Stem cell transplantation has been reported to rescue ovarian function in a preclinical mouse model of chemotherapy-induced premature ovarian failure (POF); however, maintaining the survival and self-renewal of transplanted seed cells in ovarian tissues over the long-term remains a troublesome issue. In this study we aimed to determine whether the CD44+/CD105+ human amniotic fluid cell (HuAFCs) subpopulation represent potential seed cells for stem cell transplantation treatments in POF. MATERIALS AND METHODS: The CD44+/CD105+ subpopulation were isolated from HuAFCs, cultured in vitro, and injected into a cyclophosphamide-induced mouse model of POF. RESULTS: Under continuous subculture in vitro, CD44+/CD105+ cells proliferated rapidly and expressed high levels of the proliferative markers Ki67 and survivin, as well as high levels of a number of mesenchymal stem cell biomarkers. Moreover, when red fluorescence protein (RFP)-transduced CD44+/CD105+ HuAFCs were transplanted into the ovaries of POF mice, the cells could be detected by fluorescence microscopy up to three weeks after injection. Furthermore, the BrdUrd incorporation assay and immunofluorescent staining demonstrated that CD44+/CD105+ HuAFCs underwent normal cycles of cell proliferation and self-renewal in the ovarian tissues of POF mice over the long-term. CONCLUSIONS: The mesenchymal stem cell properties and long-term in vivo survival of CD44+/CD105+ HuAFCs make them ideal seed cells for stem cell transplantation to treat POF.

Low microRNA-199a expression in human amniotic epithelial cell feeder layers maintains human-induced pluripotent stem cell pluripotency via increased leukemia inhibitory factor expression.

Human-induced pluripotent stem (iPS) cells share the same key properties as embryonic stem cells, and may be generated from patient- or disease-specific sources, which makes them attractive for personalized medicine, drug screens, or cellular therapy. Long-term cultivation and maintenance of normal iPS cells in an undifferentiated self-renewing state is a major challenge. Our previous studies have shown that human amniotic epithelial cells (HuAECs) could provide a good source of feeder cells for mouse and human embryonic stem cells, or spermatogonial stem cells, as they express endogenous leukemia inhibitory factor (LIF) at high levels. Here, we examined the effect of exogenous microRNA-199a regulation on endogenous LIF expression in HuAECs, and in turn on human iPS cell pluripotency. We found that HuAECs feeder cells transfected with microRNA-199a mutant expressed LIF at high levels, allowing iPS to maintain a high level of alkaline phosphatase activity in long-term culture and form teratomas in severe combined immunodeficient mice. The expression of stem cell markers was increased in iPS cultured on HuAECs feeder cells transfected with the microRNA-199a mutant, compared with iPS cultured on HuAECs transfected with microRNA-199a or mouse embryo fibroblasts. Taken together, these results suggested that LIF expression might be regulated by microRNA-199a, and LIF was a crucial component in feeder cells, and also was required for maintenance of human iPS cells in an undifferentiated, proliferative state capable of self-renewal.

Acetylcholinesterase is associated with apoptosis in ß cells and contributes to insulin-dependent diabetes mellitus pathogenesis.

Acetylcholinesterase (AChE) expression is pivotal during apoptosis. Indeed, AChE inhibitors partially protect cells from apoptosis. Insulin-dependent diabetes mellitus (IDDM) is characterized in part by pancreatic ß-cell apoptosis. Here, we investigated the role of AChE in the development of IDDM and analyzed protective effects of AChE inhibitors. Multiple low-dose streptozotocin (MLD-STZ) administration resulted in IDDM in a mouse model. Western blot analysis, cytochemical staining, and immunofluorescence staining were used to detect AChE expression in MIN6 cells, primary ß cells, and apoptotic pancreatic ß cells of MLD-STZ-treated mice. AChE inhibitors were administered intraperitoneally to the MLD-STZ mice for 30 days. Blood glucose, plasma insulin, and creatine levels were measured, and glucose tolerance tests were performed. The effects of AChE inhibitors on MIN6 cells were also evaluated. AChE expression was induced in the apoptotic MIN6 cells and primary ß cells in vitro and pancreatic islets in vivo when treated with STZ. Induction and progressive accumulation of AChE in the pancreatic islets were associated with apoptotic ß cells during IDDM development. The administration of AChE inhibitors effectively decreased hyperglycemia and incidence of diabetes, and restored plasma insulin levels and plasma creatine clearance in the MLD-STZ mice. AChE inhibitors partially protected MIN6 cells from the damage caused by STZ treatment. Induction and accumulation of AChE in pancreatic islets and the protective effects of AChE inhibitors on the onset and development of IDDM indicate a close relationship between AChE and IDDM.

Use of human amniotic epithelial cells as a feeder layer to support undifferentiated growth of mouse spermatogonial stem cells via epigenetic regulation of the Nanog and Oct-4 promoters.

Spermatogonial stem cells (SSCs) are defined by unique properties like other stem cells. However, there are two major challenges: long-term cultivation of normal SSCs into stable cell lines and maintaining the SSCs as undifferentiated and capable of self-renewal. Here, we compared different culture methods for mouse SSCs isolated and cultured from testicular tissue. We found that human amniotic epithelial cells (hAECs) can behave as feeder cells, allowing mouse SSCs to maintain a high level of alkaline phosphatase (AP) activity when cultured long-term. Also, we observed that expression of Nanog, Oct-4 and other important stem cells markers were higher in mouse SSCs cultured on hAECs compared to those cultured on MEF or without any feeder cells. Furthermore, we demonstrated that the CpG islands of the Nanog and Oct-4 promoters were hypomethylated in cells cultured on hAECs. In addition, mouse SSCs cultured on hAECs exhibited higher levels of H3AC and H3K4Me3 in the Nanog and Oct-4 promoters than those cultured on MEF or without feeder cells. Taken together, these results suggest that the hAEC-induced epigenetic modifications at the Nanog and Oct-4 locus could be a key mechanism for maintaining mouse SSCs in an undifferentiated state capable of self-renewal.

Human Amniotic Epithelial Stem Cell-Derived Retinal Pigment Epithelium Cells Repair Retinal Degeneration.

Age-related macular degeneration (AMD), featured with dysfunction and loss of retinal pigment epithelium (RPE), is lacking efficient therapeutic approaches. According to our previous studies, human amniotic epithelial stem cells (hAESCs) may serve as a potential seed cell source of RPE cells for therapy because they have no ethical concerns, no tumorigenicity, and little immunogenicity. Herein, trichostatin A and nicotinamide can direct hAESCs differentiation into RPE like cells. The differentiated cells display the morphology, marker expression and cellular function of the native RPE cells, and noticeably express little MHC class II antigens and high level of HLA-G. Moreover, visual function and retinal structure of Royal College of Surgeon (RCS) rats, a classical animal model of retinal degeneration, were rescued after subretinal transplantation with the hAESCs-derived RPE like cells. Our study possibly makes some contribution to the resource of functional RPE cells for cell therapy. Subretinal transplantation of hAESCs-RPE could be an optional therapeutic strategy for retinal degeneration diseases.

Cynomorium songaricum extracts functionally modulate transporters of gamma-aminobutyric acid and monoamine.

Cynomorium songaricum Rupr. (SY) is a central nervous system-oriented herb material that has actions of anti-dementia, anti-epilepsy, and anti-stress. It is unclear whether SY would be biologically active in functionally regulating neurotransmitter transporters. Here, we assessed these potential actions using Chinese hamster ovary cells expressing gamma-aminobutyric acid (GABA) transporter (GAT-1), dopamine transporter (DAT), norepinephrine transporter (NET), or serotonin transporter (SERT) (i.e. G1, D8, N1, or S6 cells, respectively). It was shown that SY extracts, such as SYw, SYa, SYp, SYc, SYe, and SYb (SY water, ethanol, petroleum ether, chloroform, ethyl acetate, and n-butyl alcohol extract, respectively) increased dopamine/norepinephrine (DA/NE) uptake by corresponding D8/N1 cells and decreased gamma-aminobutyric acid/serotoin (GABA/5HT) uptake by corresponding G1/S6 cells; wherein, the potency or efficacy of SYc for up-regulating DA/NE uptake and that of SYb for inhibiting GABA/5HT uptake were relatively stronger. Additionally, GABA/5H-uptake inhibition by SY extracts were also seen in cortical synaptosomes, and DA/NE-uptake enhancement by SYc was dependent on the activity of DAT and NET. Thus, SY extracts especially SYc and SYb are novel neurotransmitter-transporter modulators functioning as DAT/NET activators and/or GAT-1/SERT inhibitors.

Treatment of intracerebral haemorrhage in rats with intraventricular transplantation of human amniotic epithelial cells.

We explored the effects on brain oedema and neurological functional recovery after transplantation of hAECs (human amniotic epithelial cells) into the lateral ventricle of rats with ICH (intracerebral haemorrhage). hAECs were isolated from human term placenta and seeded for primary culture. We delivered hAECs labelled with Hoechst33258 and transfected with EGFP (enhanced green fluorescent protein) gene using lentiviral vectors into ICH rat models. The behaviour of the animals and brain oedema were evaluated after 28 days, and brain sections were made for morphological and immunohistochemical analyses with fluorescence microscopy. Our results were as follows. Transplanted hAECs were observed along the lateral wall and survived for at least 4 weeks. Some of the cells were stained with human specific antibody to vimentin and nestin. Around the injury site, activated microglia stained with OX42 were reduced. The water content of ICH rats decreased in the treatment group. The behaviour test scores were improved in the treatment group compared with those in the control groups. In conclusion, hAECs cannot only survive in the lateral ventricle of ICH rats after transplantation, but also express vimentin and nestin. hAEC transplantation reduced brain oedema and improved the motor deficits of ICH rats.

Discovery and synthesis of novel luteolin derivatives as DAT agonists.

Luteolin, 5,7-dihydroxy-2-(3,4-dihydroxyphenyl)-4H-chromen-4-one, has been proposed and proved to be a novel dopamine transporter (DAT) activator. In order to develop this potential of luteolin, a series of novel luteolin derivatives were designed, synthesized, and evaluated for their DAT agonistic activities, utilizing constructed Chinese hamster ovary (CHO) cell lines stably expressing rat DAT. Biological screening results demonstrated that luteolin derivatives 1d, 1e, and 4c carry great DAT agonistic potency (EC(50)=0.046, 0.869, and 1.375µM, respectively) compared with luteolin 8 (EC(50)=1.45±0.29µM). Luteolin derivative 1d, notably, exhibited a 32-fold-higher DAT agonistic potency than luteolin. These luteolin derivatives represent a novel DAT agonist class, from which lead compounds useful for exploration of additional novel DAT agonists could be drawn.

Cancer stem-like cells can be isolated with drug selection in human ovarian cancer cell line SKOV3.

One emerging model for the development of drug-resistant tumors utilizes a pool of self-renewing malignant progenitors known as cancer stem cells (CSCs) or cancer-initiating cells (CICs). The purpose of this study was to propagate such CICs from the ovarian cancer cell line SKOV3. The SKOV3 sphere cells were selected using 40.0 micromol/l cisplatin and 10.0 micromol/l paclitaxel in serum-free culture system supplemented with epidermal growth factor, basic fibroblast growth factor, leukemia inhibitory factor, and insulin or standard serum-containing system. These cells formed non-adherent spheres under drug selection (cisplatin and paclitaxel) and serum-free culture system. The selected sphere cells are more resistant to cisplatin, paclitaxel, adriamycin, and methotrexate. Importantly, the sphere cells have the properties of self-renewal, with high expression of the stem cell genes Nanog, Oct4, sox2, nestin, ABCG2, CD133, and the stem cell factor receptor CD117 (c-kit). Consistently, flow cytometric analysis revealed that the sphere cells have a much higher percentage of CD133(+)/CD117(+)-positive cells (71%) than differentiated cells (33%). Moreover, the SKOV3 sphere cells are more tumorigenic. Furthermore, cDNA microarray and subsequent ontological analyses revealed that a large proportion of the classified genes were related to angiogenesis, extracellular matrix, integrin-mediated signaling pathway, cell adhesion, and cell proliferation. The subpopulation isolation from the SKOV3 cell line under this culture system offers a suitable in vitro model for studying ovarian CSCs in terms of their survival, self-renewal, and chemoresistance, and for developing therapeutic drugs that specifically interfere with ovarian CSCs.