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Zinc is an essential nutrient that is important for normal brain development. Zinc deficiency has been linked to aberrant neurological development and functioning. However, the molecular mechanisms underlying Zinc deficiency-induced neurological disorders remain largely elusive. In the present study, we showed that the proliferation of C17.2 neural stem cells (NSCs) was evidently impaired after exposed to low levels of Zinc chelator, N,N,N',N'-tetrakis-(2-pyridylmethy) ethylenediamine (TPEN). In addition, we found that TPEN-induced proliferative deficit of NSCs was related with significant downregulation of Wnt/β-catenin signaling. Zinc deficiency impaired the proliferation of neural stem cells in dose- and time-dependent manners. Western blot revealed that the levels of p-Ser9-glycogensynthase kinase-3β (p-GSK-3β) and β-catenin were remarkably downregulated during TPEN-induced C17.2 proliferative impairment. Moreover, immunofluorescent analysis indicated that the level of nuclear β-catenin was apparently decreased following TPEN exposure. Furthermore, application with GSK-3β inhibitor lithium chloride (LiCl) reversed TPEN-induced downregulation of β-catenin and impairment of cell proliferation. Flow cytometry analysis also showed that TPEN-induced impairment of NSC proliferation could be reversed by LiCl. Taken together, these findings suggested that the disturbance of canonical Wnt/β-catenin signaling pathway partially accounted for Zinc deficiency-induced proliferative impairment of NSCs., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Lotus flower polysaccharide (LFP) and lotus seedpod polysaccharide (LSP) were separated by water extract–alcohol precipitation, and their structures and biological activities were investigated. The results of monosaccharide composition showed that LFP and LSP were composed of nine monosaccharides, fucose, rhamnose, arabinose, glucose, galactose, mannose, fructose, galacturonic acid, and glucuronic acid, with the molar percentages of 0.18: 0.43: 2.26: 45.22: 32.14: 4.28: 8.20: 6.28: 1.01 and 2.70: 1.02: 8.15: 45.63: 20.63: 1.44: 2.59: 16.45. LSP and LFP exhibited molecular weights of 9.37 × 104 Da and 1.24 × 106 Da, respectively. SEM showed that LFP and LSP have similar structures; XRD analysis showed that both polysaccharides had crystalline structure and amorphous structure. The results of ABTS+, DPPH, hydroxyl radical scavenging experiment, and a reducing power experiment showed that LFP and LSP had good antioxidant capacity. Cell viability findings showed that polysaccharide concentrations of lotus flower and lotus seedpod could enhance cellular proliferation ranging from 25 to 400 μg/mL without cytotoxicity. By inducing the production of crucial proteins in the TLR4/NF-κB pathway, LFP and LSP were able to induce autophagy in RAW264.7, according to the results of the RT-PCR and Western blotting assays. [ABSTRACT FROM AUTHOR]

Background: Accumulating evidence demonstrated that NANOG1, the key transcription factor for embryonic stem cells, is associated with human cancers. NANOGP8, one of the pseudogenes in NANOG gene family, contains an intact open reading frame and also said to be expressed in cancer tissues. Therefore, a systematic study is greatly needed to address the following questions: among NANOG1 and NANOGP8, which gene is the main contributor for NANOG expression in cancer cells and which one is the key regulator responsible for stemness, epithelial-mesenchymal transition (EMT), metastasis, chemoresistance and other malignant phenotypes. Here we try to explore these issues with gastric adenocarcinoma cell lines in vitro using variety of molecular and cellular techniques. Methods: Special primers were designed to distinguish PCR products from NANOG1 and NANOGP8. Sphere-forming cells were cultured with serum-free and selective medium. A stable cell line was established with infection of lentivirus containing NANOGP8. qPCR was performed to measure NANOGP8 expression and its association with stemness, EMT and CSC markers in adherent cells and sphere-forming cells. Western blot analysis was deployed to confirm results of the transcript analysis. Experiments of cell proliferation, migration, invasion, clonogenic assay, sphere cell growth assays, cell cycle analysis, β-catenin accumulation and translocation in nucleus, and drug resistance were conducted to measure the impact of NANOGP8 on malignant statuses of gastric cancer cells. Immunofluorescence staining was used to analyze cell subpopulations with different markers. Results: NANOGP8 is mainly responsible for NANOG expression in sphere-forming (stem cell-like) cells derived from gastric cancer cell lines regardless their differentiation status. Ectopic expression of NANOGP8 significantly up-regulates stemness transcription factors, EMT inducers, and cancer stem cell markers (CSC) including Lgr5. NANOGP8 also promotes expression of the signature genes vimentin and N-caderin for mesenchymal cells and down-regulates the signature gene E-caderin for epithelial cells whereby confer the cells with mesenchymal cell phenotype. In NANOGP8 over-expressed adherent and sphere-forming cells, Lgr5+ cells are significantly increased. Ectopic expression of NANOGP8 endows gastric cells with enhanced proliferation, migration, invasion, sphere-forming and clonogenic capacity, and chemoresistance. NANOGP8 expression also enhances β-catenin accumulation in nucleus and strengthens Wnt signal transduction. Conclusion: NANOGP8 is the main regulator of gastric cancer stem cells. It is closely associated with EMT, stemness, and CSC marker as well as Wnt signal pathway. NANOGP8 is correlated with cell proliferation, migration, invasion, clonogenic capacity, β-catenin accumulation in nucleus, and chemoresistance in gastric cancer. NANOGP8 is a promising molecular target for clinical intervention of gastric cancer. [ABSTRACT FROM AUTHOR]

Background: Accumulating evidence supports the hypothesis that cancer stem cells (CSCs) are essential for cancer initiation, metastasis and drug resistance. However, the functional association of gastric CSC markers with stemness and epithelial-mesenchymal transition (EMT) signature genes is unclear. Methods: qPCR was performed to measure the expression profiles of stemness and EMT signature genes and their association with putative CSC markers in gastric cancer tissues, cancer cell lines and sphere cells. Western blot analysis was used to confirm the results of the transcript analysis. Cell proliferation, cell migration, drug resistance and sphere cell growth assays were conducted to measure the expansion and invasion abilities of the cells. Tumor xenograft experiments were performed in NOD/SCID mice to test cell stemness in vivo. Flow cytometry and immunofluorescence staining were used to analyze cell subpopulations. Results: The expression of LGR5 was strikingly up-regulated in sphere cells but not in cancer tissues or parental adherent cells. The up-regulation of LGR5 was also positively associated with stemness regulators (NANOG, OCT4, SOX2, and AICDA) and EMT inducers (PRRX1, TWIST1, and BMI1). In addition, sphere cells exhibited up-regulated vimentin and down-regulated E-cadherin expression. Using gene-specific primers, we found that the NANOG expression primarily originates from the retrogene NANOGP8. Western blot analysis showed that the expression of both LGR5 and NANOG is significantly higher in sphere cells. LGR5 over-expression significantly enhanced sphere cell growth, cell proliferation, cell migration and drug resistance in MGC803 cells. Tumor xenografts in nude mice showed that sphere cells are at least 10 times more efficient at tumor initiation than adherent cells. Flow cytometry analysis showed that ~20% of sphere cells are LGR5+/CD54+, but only ~3% of adherent cells are Lgr5+/CD54+. Immunofluorescence staining supports the above results. Conclusion: The LGR5-expressing fraction of CD54+ cells represents gastric cancer CSCs, in which LGR5 is closely associated with stemness and EMT core genes, and NANOG expression is mainly contributed by the retrogene NANOGP8. Sphere cells are the best starting materials for the characterization of CSCs. [ABSTRACT FROM AUTHOR]

Zinc plays an important role in the development and maintenance of central neural system. Zinc deficiency has been known to alter normal brain function, whose molecular mechanism remains largely elusive. In the present study, we established a zinc deficiency-exposed rat model, and, using western blot and immunohistochemical analyses, found that the expression of FoxO3a and p27kip1 was remarkably up-regulated in the rat brain hippocampus. Immunofluorescence assay showed that FOXO3a and p27kip1 were significantly co-localized with nestin, the marker of neural stem cells ( NSCs). Furthermore, we identified that the proportion of proliferating NSCs was markedly decreased in zinc-deficient rat hippocampaus. Using C17.2 neural stem cells, it was revealed that exposure to zinc chelator N, N, N', N'-tetrakis-(2-pyridylmethy) ethylenediamine induced the expression of FoxO3a and p27kip1, which coincided with reduced NSC proliferation. Furthermore, depletion of FoxO3a inhibited p27kip1 expression and restored the growth of NSCs. On the basis of these data, we concluded that FoxO3a/p27kip1 signaling might play a significant role in zinc deficiency-induced growth impairment of NSCs and consequent neurological disorders. [ABSTRACT FROM AUTHOR]

Abstract: Two experiments were carried out. In immune response test, the immune enhancement of propolis, oilemulsion and aluminium salt were compared in guinea pig vaccinated with inactivated porcine parvovirus (PPV) vaccine. The result showed that three adjuvants could enhance antibody titer, T lymphocyte proliferation, IL-2 and IL-4 secretion of splenic lymphocyte. The action of propolis was similar to that of oilemulsion and superior to that of aluminium salt, especially in early period of vaccination propolis could accelerate antibody production. In immune protection test, the effects of three adjuvants on PPV infection were compared in guinea pig vaccinated with PPV vaccine then challenged with PPV. The result showed that propolis and oilemulsion could enhance the antibody titer, IL-2 and IL-4 content in serum and decrease the PPV content in blood and viscera. In the effect of improving cellular immune response, the propolis was the best. These results indicated that propolis possessed better immune enhancement and would be exploited into a effective adjuvant of inactivated vaccine. [Copyright &y& Elsevier]

Abstract: In order to select the sulfated polysaccharide prescription (sPSP) with the best immunoenhancement, 270 14-day-old chickens were averagely divided into nine groups and vaccinated with ND-IV vaccine. The chickens in seven experimental groups were intramuscularly injected with three sulfated polysaccharides and their four prescriptions (sPSPs). The serum antibody and peripheral lymphocyte proliferation were measured. On day 23 after vaccination, all chickens except for Negative control group were challenged with Newcastle disease virus. The morbidity, mortality and immune protective rate were calculated and their serum antibody titers were determined. The results showed that all sulfated polysaccharides and their prescriptions could obviously or significantly enhance the immune response of ND vaccine in vaccinated chicken and increase the immune protective rate in challenged chicken. sPSP1 possessed the best efficacy, stronger than its components as well, and would be expected as a candidate of new-type immune adjuvant. [Copyright &y& Elsevier]

Abstract: The purpose of this research is to study the effect of sulfated lentinan (sLNT) on immune effect of Newcastle disease (ND) vaccine. In immune response test, 14-day-old chickens were vaccinated with ND vaccine then grouped respectively to inject three sLNTs at two doses, once a day for three successive days, taking non-sulfated lentinan (LNT) as the control. The changes of serum antibody titer and peripheral lymphocyte proliferation were determined before and after vaccination. In immune protection test, 35-day-old chickens were challenged with ND virus (NDV) after treated similar to above mentioned. The morbidity and mortality of chickens were observed, and the changes of serum antibody titer and peripheral lymphocyte proliferation were measured before and after challenge. The results showed that three modified sLNTs could significantly enhance serum antibody titer and promote lymphocyte proliferation in two experimental chickens, and reduce morbidity and mortality of chickens challenged with NDV, which were better than that of non-modified LNT. Their high doses in enhancing antibody titer and low doses in promoting lymphocyte proliferation were more preferable. These results indicated that sulfated modification could enhance the adjuvanticity of LNT and improve the immune effect of ND vaccine. sLNT2 possessed the best efficacy and would be expected as the candidate of a new-type immune adjuvant. [Copyright &y& Elsevier]