Review on the genus Polygonatum polysaccharides: Extraction, purification, structural characteristics and bioactivities.

The genus Polygonatum is gaining increasing attention from nutrition experts as well as health-conscious consumers because of its excellent performance in providing nutrients. Among these plants, Polygonatum sibiricum and Polygonatum odoratum have been selected for inclusion in China's Medicinal Food Directory due to their high safety profile. Polysaccharides are considered the main functional component and one of the main active ingredients of the plant. In addition, polysaccharides from genus Polygonatum have a variety of nutritional, biological and health-promoting properties, such as immunomodulatory, anti-inflammatory, cardiovascular protective, neuroprotective, antitumor, antidiabetic, antiosteoporosis, and hepatoprotective properties. This paper reviews the origin, extraction, purification, structural characteristics, biological activity, safety, toxicological evaluation, and structure-activity relationship of polysaccharides from the genus Polygonatum. Ultimately, we hope that this work can provide a more useful reference for understanding the polysaccharide structure and developing of new functional foods from polysaccharides of the genus Polygonatum.

Shp2 in uterine stromal cells critically regulates on time embryo implantation and stromal decidualization by multiple pathways during early pregnancy.

Approximately 75% of failed pregnancies are considered to be due to embryo implantation failure or defects. Nevertheless, the explicit signaling mechanisms governing this process have not yet been elucidated. Here, we found that conditional deletion of the Shp2 gene in mouse uterine stromal cells deferred embryo implantation and inhibited the decidualization of stromal cells, which led to embryonic developmental delay and to the death of numerous embryos mid-gestation, ultimately reducing female fertility. The absence of Shp2 in stromal cells increased the proliferation of endometrial epithelial cells, thereby disturbing endometrial epithelial remodeling. However, Shp2 deletion impaired the proliferation and polyploidization of stromal cells, which are distinct characteristics of decidualization. In human endometrial stromal cells (hESCs), Shp2 expression gradually increased during the decidualization process. Knockout of Shp2 blocked the decidual differentiation of hESCs, while Shp2 overexpression had the opposite effect. Shp2 knockout inhibited the proliferation of hESCs during decidualization. Whole gene expression profiling analysis of hESCs during the decidualization process showed that Shp2 deficiency disrupted many signaling transduction pathways and gene expression. Analyses of hESCs and mouse uterine tissues confirmed that the signaling pathways extracellular regulated protein kinases (ERK), protein kinase B (AKT), signal transducer and activator of transcription 3 (STAT3) and their downstream transcription factors CCAAT/enhancer binding protein ß (C/EBPß) and Forkhead box transcription factor O1 (FOXO-1) were involved in the Shp2 regulation of decidualization. In summary, these results demonstrate that Shp2 plays a crucial role in stromal decidualization by mediating and coordinating multiple signaling pathways in uterine stromal cells. Our discovery possibly provides a novel key regulator of embryo implantation and novel therapeutic target for pregnancy failure.

Teclistamab is an active T cell-redirecting bispecific antibody against B-cell maturation antigen for multiple myeloma.

B-cell maturation antigen (BCMA), a member of the tumor necrosis factor family of receptors, is predominantly expressed on the surface of terminally differentiated B cells. BCMA is highly expressed on plasmablasts and plasma cells from multiple myeloma (MM) patient samples. We developed a BCMAxCD3 bispecific antibody (teclistamab [JNJ-64007957]) to recruit and activate T cells to kill BCMA-expressing MM cells. Teclistamab induced cytotoxicity of BCMA+ MM cell lines in vitro (H929 cells, 50% effective concentration [EC50] = 0.15 nM; MM.1R cells, EC50 = 0.06 nM; RPMI 8226 cells, EC50 = 0.45 nM) with concomitant T-cell activation (H929 cells, EC50 = 0.21 nM; MM.1R cells, EC50 = 0.1 nM; RPMI 8226 cells, EC50 = 0.28 nM) and cytokine release. This activity was further increased in the presence of a γ-secretase inhibitor (LY-411575). Teclistamab also depleted BCMA+ cells in bone marrow samples from MM patients in an ex vivo assay with an average EC50 value of 1.7 nM. Under more physiological conditions using healthy human whole blood, teclistamab mediated dose-dependent lysis of H929 cells and activation of T cells. Antitumor activity of teclistamab was also observed in 2 BCMA+ MM murine xenograft models inoculated with human T cells (tumor inhibition with H929 model and tumor regression with the RPMI 8226 model) compared with vehicle and antibody controls. The specific and potent activity of teclistamab against BCMA-expressing cells from MM cell lines, patient samples, and MM xenograft models warrant further evaluation of this bispecific antibody for the treatment of MM. Phase 1 clinical trials (monotherapy, #NCT03145181; combination therapy, #NCT04108195) are ongoing for patients with relapsed/refractory MM.

Blockade of VLA4 sensitizes leukemic and myeloma tumor cells to CD3 redirection in the bone marrow microenvironment.

Redirecting T cells to specifically kill malignant cells has been validated as an effective anti-cancer strategy in the clinic with the approval of blinatumomab for acute lymphoblastic leukemia. However, the immunosuppressive nature of the tumor microenvironment potentially poses a significant hurdle to T cell therapies. In hematological malignancies, the bone marrow (BM) niche is protective to leukemic stem cells and has minimized the efficacy of several anti-cancer drugs. In this study, we investigated the impact of the BM microenvironment on T cell redirection. Using bispecific antibodies targeting specific tumor antigens (CD123 and BCMA) and CD3, we observed that co-culture of acute myeloid leukemia or multiple myeloma cells with BM stromal cells protected tumor cells from bispecific antibody-T cell-mediated lysis in vitro and in vivo. Impaired CD3 redirection cytotoxicity was correlated with reduced T cell effector responses and cell-cell contact with stromal cells was implicated in reducing T cell activation and conferring protection of cancer cells. Finally, blocking the VLA4 adhesion pathway in combination with CD3 redirection reduced the stromal-mediated inhibition of cytotoxicity and T cell activation. Our results lend support to inhibiting VLA4 interactions along with administering CD3 redirection therapeutics as a novel combinatorial regimen for robust anti-cancer responses.

A T-cell-redirecting bispecific G-protein-coupled receptor class 5 member D x CD3 antibody to treat multiple myeloma.

T-cell-mediated approaches have shown promise in myeloma treatment. However, there are currently a limited number of specific myeloma antigens that can be targeted, and multiple myeloma (MM) remains an incurable disease. G-protein-coupled receptor class 5 member D (GPRC5D) is expressed in MM and smoldering MM patient plasma cells. Here, we demonstrate that GPRC5D protein is present on the surface of MM cells and describe JNJ-64407564, a GPRC5DxCD3 bispecific antibody that recruits CD3+ T cells to GPRC5D+ MM cells and induces killing of GPRC5D+ cells. In vitro, JNJ-64407564 induced specific cytotoxicity of GPRC5D+ cells with concomitant T-cell activation and also killed plasma cells in MM patient samples ex vivo. JNJ-64407564 can recruit T cells and induce tumor regression in GPRC5D+ MM murine models, which coincide with T-cell infiltration at the tumor site. This antibody is also able to induce cytotoxicity of patient primary MM cells from bone marrow, which is the natural site of this disease. GPRC5D is a promising surface antigen for MM immunotherapy, and JNJ-64407564 is currently being evaluated in a phase 1 clinical trial in patients with relapsed or refractory MM (NCT03399799).

Preparation and properties of aramid pulp/acrylonitrile-butadiene rubber composites.

In this investigation, aramid pulp (AP) was introduced into acrylonitrile-butadiene rubber (NBR)-based composites in various amounts by two different introduction methods. An AP/NBR predispersion was applied to improve the AP dispersion in the matrix, and its effects on the characteristics and properties of the composites were studied. The results showed that the optimum curing time of the compounds was affected by the AP introduction method due to heat generation at different mixing stages. The addition of AP affected the swelling properties and significantly improved the hardness, modulus and tear strength. The tensile strength decreased and then increased with increasing AP content. The AP predispersion obviously further improved the tensile strength of the composites with AP content above 7.5 phr owing to better fiber network formation inside the rubber matrix during the stretching process. The dynamic mechanical properties were not sensitive to the AP introduction method. The addition of AP was conducive to the wear resistance, and the dispersion improvement could further enhance the uniformity of the worn surface and mitigate crack generation.

Study on water resistance and tribological behaviours of basalt fibre/acrylonitrile-butadiene rubber composites under water lubrication at various temperatures.

In this study, the effects of water ageing on characteristics and properties of basalt fibre (BF)/acrylonitrile-butadiene rubber (NBR) composites were investigated, and the tribological behaviours of the composites that slide against the stainless-steel counterpart under water lubrication at 30-70 °C were the main focus. Results showed that with the water temperature increase, the hardness and tear strength of the water-aged samples decreased. Furthermore, both the friction coefficient (COF) and specific wear rate (W s) of the composites increased with the temperature. The content and the orientation of BFs had no obvious effect on the COF, whereas the parallel-aligned BFs were effective at improving the wear resistance of the composites at both 30 °C and 70 °C.

Characterization of the mechanism of protection mediated by CS-D7, a monoclonal antibody to Staphylococcus aureus iron regulated surface determinant B (IsdB).

We previously reported the development of a human monoclonal antibody (CS-D7, IgG(1)) with specificity and affinity for the iron regulated surface determinant B (IsdB) of Staphylococcus aureus. CS-D7 mediates opsonophagocytic killing in vitro and protection in a murine sepsis model. In light of recent data indicating that IsdB specific T cells (CD4+, Th17), not Ab, mediate protection after vaccination with IsdB, it is important to investigate the mechanism of protection mediated by CS-D7. The mAb was examined to determine if it blocked heme binding to IsdB in vitro. The mAb was not found to have heme blocking activity, nor did it prevent bacterial growth under in vivo conditions, in an implanted growth chamber. To assess the role of the mAb Fc a point mutation was introduced at aa 297 (CS-D7·N297A). This point mutation removes Fc effector functions. In vitro analysis of the mutein confirmed that it lacked measurable binding to FcγR, and that it did not fix complement. The mutein had dramatically reduced in vitro opsonic OP activity compared to CS-D7. Nonetheless, the mutein conferred protection equivalent to the wild type mAb in the murine sepsis model. Both wild type and mutein mAbs were efficacious in FcγR deletion mice (including both FcγRII(-/-) mice and FcγRIII(-/-) mice), indicating that these receptors were not essential for mAb mediated protection in vivo. Protection mediated by CS-D7 was lost in Balb/c mice depleted of C3 with cobra venom factor (CFV), was lost in mice depleted of superoxide dismutase (SOD) in P47phox deletion mice, and as previously reported, was absent in SCID mice (Joshi et al., 2012). Enhanced clearance of S. aureus in the liver of CS-D7 treated mice and enhanced production of IFN-γ, but not of IL17, may play a role in the mechanism of protection mediated by the mAb. CS-D7 apparently mediates survival in challenged mice through a mechanism involving complement, phagocytes, and lymphocytes, but which does not depend on interaction with FcγR, or on blocking heme uptake.

[Anthocyanidin inhibits immunoglobulin E-mediated allergic response in mast cells].

This study is to investigate the anti-allergic effect of anthocyanidin and to explore its possible mechanism. The experiments of passive cutaneous anaphylaxis reaction (PCA) and colorimetry were used to determine the effect of anthocyanidin on degranulation of mast cells in vivo. For in vitro study, various concentrations of anthocyanidin (100, 50 and 25 micromol x L(-1)) were added to the culture medium of mast cells cultured with 100 microg x L(-1) of dinitrophenyl (DNP) specific IgE overnight. The azelastine (100 micromol x L(-1)) was selected as the positive control. The antigen (DNP-human serum albumin, DNP-HAS)-induced release of degranulation was measured by enzymatic assay, histamine was determined by EIA, and interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-alpha) were measured by Western blotting, separately. In addition, the effects of anthocyanidin on phosphorylation of NF-kappaB, p38MAPK and Akt were observed by Western blotting. The results showed that treatments with anthocyanidin (100 and 50 mg x kg(-1)) were followed by a decrease in PCA of rats. Anthocyanidin (100 and 50 micromol x L(-1)) obviously suppressed the degranulation from mast cells, whereas results from anthocyanidin (100 and 50 micromol x L(-1)) group indicated significant inhibitory effect on histamine, the calcium uptake, TNF-alpha, IL-6, phosphorylation of NF-kappaB, p38MAPK and Akt of mast cells induced by antigen. Anthocyanidin may suppress the anaphylactic reaction by inhibiting the action of mast cells. NF-kappaB, p38MAPK and Akt at least in part contribute to this event.

Trypsin as a novel potential absorption enhancer for improving the transdermal delivery of macromolecules.

OBJECTIVES: The aim was to assess the effect of trypsin on the transdermal delivery of macromolecules by applying its specific biochemical properties to the stratum corneum of the skin. METHODS: Fluorescein isothiocyanate (FITC)-labelled dextrans (FDs), with molecular weights of 4 to 250 kDa, and FITC-insulin were used as model macromolecules and a model polypeptide, and the in-vitro transdermal permeation experiments, with or without trypsin (0.1-2.5%), were carried out using rat skin and cultured human epidermis. The mechanism for the enhancement of trypsin was also studied using fluorescence and conventional light microscopy. KEY FINDINGS: Trypsin significantly increased the transdermal permeability of all FDs through the rat skin (2.0- to 10.0-fold). It also markedly enhanced the permeation of FD4 through three-dimensional cultured human epidermis (3.1-fold), which was used to evaluate the transport pathways other than the transfollicular route. Furthermore, the permeation flux of FITC-insulin was increased by 10.0-fold with trypsin pretreatment (from 0.02 +/- 0.00 to 0.20 +/- 0.07 microg/cm(2) per h). Mechanistic studies indicated that trypsin affects both the intercellular pathway and the hair follicular route, and may alter stratum corneum protein structures, thereby affecting skin barrier properties. CONCLUSIONS: This study suggests that trypsin could be effective as a biochemical enhancer for the transdermal delivery of macromolecules including peptide and protein drugs.

Modulation by celecoxib and difluoromethylornithine of the methylation of DNA and the estrogen receptor-alpha gene in rat colon tumors.

The ability of celecoxib and alpha-difluoromethylornithine (DFMO) to modulate the DNA hypomethylation and the hypermethylation of the estrogen receptor (ER)-alpha gene in colon tumors was evaluated as potential biomarkers for chemoprevention. Colon tumors were induced in rats by azoxymethane. Celecoxib (500 mg/kg), DFMO (100, 1000 and 3000 mg/kg) or celecoxib + 1000 mg/kg DFMO were administered in the diet for 7 or 28 days prior to death at week 37. Relative to the normal colon mucosa, colon tumors contained global hypomethylated DNA but simultaneous hypermethylation of the promoter plus exon-1 region of the ER-alpha gene. Limited treatment with celecoxib (500 p.p.m. in diet) or DFMO (1000 or 3000 p.p.m. in diet) reversed the DNA hypomethylation. Administering 1000 and 3000 p.p.m. DFMO for 7-days decreased the number of methylated CpG sites in the ER-alpha gene from 5.00 +/- 0.95 to 3.83 +/- 0.75 and 1.75 +/- 0.49 these levels were further reduced to 0.50 +/- 0.26 following administration of 1000 mg/kg for 28 days. Celecoxib administered for 7 and 28 days reduced the number of methylated sites to 4.25 +/- 0.48 and 1.5 +/- 0.50. The combination containing celecoxib and DFMO reduced the number of methylated sites to 0.20 +/- 0.20 at both 7 and 28 days. In parallel with the hypermethylation of the ER-alpha gene, the mRNA expression of the gene was decreased in colon tumors and was increased by celecoxib, DFMO or the combination. Celecoxib and DFMO reversed DNA hypomethylation and the hypermethylation of the ER-alpha gene in colon tumors supporting the hypothesis that modulation of methylation is a biomarker of chemoprevention.

Hypomethylation of DNA and the insulin-like growth factor-II gene in dichloroacetic and trichloroacetic acid-promoted mouse liver tumors.

Dichloroacetic acid (DCA) and trichloroacetic acid (TCA) are mouse liver carcinogens. DNA hypomethylation is a common molecular event in cancer that is induced by DCA and TCA. Hypomethylation of DNA and the insulin-like growth factor-II (IGF-II) gene was determined in DCA- and TCA-promoted liver tumors. Mouse liver tumors were initiated by N-methyl-N-nitrosourea and promoted by either DCA or TCA. By dot-blot analysis using an antibody for 5-methylcytosine, the DNA in DCA- and TCA-promoted tumors was demonstrated to be hypomethylated. The methylation status of 28 CpG sites in the differentially methylated region-2 (DMR-2) of mouse IGF-II gene was determined. In liver, 79.3 +/- 1.7% of the sites were methylated, while in DCA- and TCA-treated mice, only 46.4 +/- 2.1% and 58.0 +/- 1.7% of them were methylated and 8.7 +/- 2.6% and 10.7 +/- 7.4% were methylated in tumors. The decreased methylation found in liver from mice exposed to DCA or TCA occurred only in the upstream region of DMR-2, while in tumors it occurred throughout the probed region. mRNA expression of the IGF-II gene was increased in DCA- and TCA-promoted liver tumors but not in non-involved liver from DCA- and TCA-exposed mice. The results support the hypothesis that DNA hypomethylation is involved in the mechanism for the tumorigenicity of DCA and TCA.

Effect of budesonide on the methylation and mRNA expression of the insulin-like growth factor 2 and c-myc genes in mouse lung tumors.

The use of surrogate end-point biomarkers could help in the development of chemopreventive agents. To define potential surrogate end-point biomarkers, the ability of budesonide to decrease mRNA expression of the insulin-like growth factor-2 (Igf-II) and c-myc genes and to cause the remethylation of the genes was investigated in lung tumors. Lung tumors were induced in female strain A mice by administering i.p. 16 mg/kg vinyl carbamate for 2 consecutive wk or by a single dose of 100 mg/kg benzo[a]pyrene (B[a]P). Thirty-four weeks later, the mice given vinyl carbamate received budesonide (0.6 or 2.4 mg/kg diet) for 7 d and then were killed. Mice were killed 24 wk after administration of B[a]P. The mRNA expression of the Igf-II and c-myc genes was increased in lung tumors relative to normal lung tissue. Budesonide decreased mRNA expression of both genes in tumors. The methylation status of 27 CpG sites in the differentially methylated region 2 in the Igf-II gene was determined with the bisulfite-treated DNA-sequencing procedure. The numbers of methylated CpG sites were 17-21 in normal lung (70.4 +/- 2.6%); 0-2, and 1-2 in lung tumors induced by vinyl carbamate and B[a]P (4.9 +/- 1.2% and 4.6 +/- 1.2%, respectively); and 4-5 or 7-16 in tumors after treatment with 0.6 or 2.4 mg/kg budesonide (16.0 +/- 1.2% and 46.2 +/- 5.1%, respectively). Thus, lung tumors had strikingly less methylated CpG sites than normal lung tissue, while even limited treatment with budesonide resulted in remethylation of the CpG sites in tumors. With HpaII digestion followed by Southern blot analysis, the internal cytosine of CCGG sites in the c-myc gene was found to be methylated in normal lung tissue, whereas some of the sites were unmethylated in lung tumors. Treatment for 7 d with budesonide resulted in the remethylation of these sites. In conclusion, mouse lung tumors showed decreased methylation of the Igf-II and c-myc genes that was associated with increased expression of these genes. Budesonide treatment caused remethylation and decreased expression of both genes. The results support the possibility of using decreased mRNA expression and remethylation of the Igf-II and c-myc genes as biomarkers for the efficacy of budesonide.

Prevention of mouse lung tumors by budesonide and its modulation of biomarkers.

Chemopreventive drugs have the potential to decrease the morbidity and mortality of lung cancer. The development of these drugs could be expedited by the application of surrogate end-point biomarkers that demonstrate chemopreventive efficacy. In this study, the ability of budesonide to prevent lung tumors in mice was characterized further and its effects on biomarkers were determined. Lung tumors were induced in female strain A mice by vinyl carbamate (16 mg/kg) administered once weekly for 2 consecutive weeks. Four weeks later the mice started to receive 0.6, 1.2 or 2.4 mg/kg budesonide continually in the diet until killed at week 20. Budesonide caused a dose-dependent decrease in the multiplicity of lung tumors of 25, 58 and 82%, respectively. Budesonide (2.4 mg/kg diet) administered starting at weeks 4, 10 or 16, decreased tumor multiplicity by 82, 66 and 30% at week 20. Administering 2.4 mg/kg budesonide at weeks 4-20 or 20-35 and killing the mice at week 35 did not significantly decrease the yield of tumors, although both treatment regimens did decrease the size of the tumors and the progression of adenomas to carcinomas. Thus, budesonide delayed the appearance of lung tumors and decreased their growth and progression to carcinomas. To determine the effect of limited exposure to budesonide on biomarkers, it was administered for only 7 days prior to death at week 35. Budesonide decreased the proliferating cell nuclear antigen labeling in lung adenomas, carcinomas, parenchyma and bronchial airways by 87.6, 59.0, 41.1 and 25.4%, respectively. Budesonide treatment also increased the protein level of the p21 and p27 genes and increased the mRNA level of p21. Thus, short-term treatment with budesonide modulated biological and molecular end-points in lung tumors that might be developed further as biomarkers for its clinical chemopreventive efficacy in the lung.

Effects of carboplatin on amino acid chemistry in chinchilla cochlear nucleus.

Carboplatin, a drug widely used against solid head and neck tumors, selectively destroys cochlear inner hair cells and type I auditory nerve fibers in chinchilla. This should affect neurotransmitter chemistry, involving amino acids, where the type I auditory nerve fibers terminate in the cochlear nucleus. Using microdissection combined with high-performance liquid chromatography, amino acid concentrations were mapped in the cochlear nuclei of chinchillas injected intraperitoneally 6-8 weeks earlier with 100 mg/kg carboplatin and in those of control animals. Glutamate concentrations were 23% lower in the anteroventral cochlear nucleus (AVCN) and 40% lower in the posteroventral cochlear nucleus (PVCN) of carboplatin-injected chinchillas as compared to controls, while aspartate concentrations were 18% lower in AVCN and 27% lower in PVCN. Using a fluorometric assay, activities of glutaminase, an enzyme which catalyzes glutamate synthesis, were 30% lower in AVCN and 38% lower in PVCN of carboplatin-injected chinchillas. Concentrations of glutamine, gamma-aminobutyrate, and glycine were also lower in some ventral and dorsal cochlear nucleus regions of treated animals. These changes probably result mainly from both primary and later effects of reduced type I auditory nerve fiber input to the cochlear nucleus.