朝鲜淫羊藿酸性多糖的理化特性及对HepG2细胞脂质堆积的改善作用＊

目的 对比研究朝鲜淫羊藿酸性多糖酯化还原前后的理化特性，并探讨其改善油酸诱导的肝癌HepG2细胞脂质堆积活性的差异。方法 采用高效凝胶渗透色谱法测定朝鲜淫羊藿酸性多糖（EFPA）的均一性和分子量，高效液相色谱法测定EFPA和酯化还原后朝鲜淫羊藿酸性多糖（EFPA-R）的单糖组成；采用油酸（OA）处理HepG2细胞诱导建立脂质蓄积模型，不同浓度EFPA与EFPA-R（10、30、100、300 μg·mL^-1）分别和OA共同作用于细胞24 h，采用CCK-8试剂盒测定细胞存活率，油红O染色观察细胞内脂滴蓄积情况，并采用试剂盒测定细胞内总胆固醇（TC）、甘油三酯（TG）含量。结果 EFPA为成分均一的多糖组分，分子量为125.8 kDa，由甘露糖、葡萄糖、半乳糖、葡萄糖醛酸和阿拉伯糖组成，摩尔比为1.7∶7.4∶1.4∶1.8∶1.0，葡萄糖占比最大，EFPA-R由甘露糖、葡萄糖、半乳糖和阿拉伯糖组成，摩尔比为0.8∶10.6∶2.1∶1.0；在10-300 μg·mL^-1范围内，EFPA和EFPA-R对HepG2细胞的抑制作用较弱，作为给药浓度；与空白组相比，模型组细胞中TC、TG含量显著升高（P < 0.01），细胞内红色脂滴显著增多，与模型组相比，EFPA可显著降低细胞中TC、TG含量（P < 0.01），明显减少细胞内红色脂滴（P < 0.05或P < 0.01），EFPA-R干预后细胞则无明显变化。结论 EFPA可明显改善HepG2细胞脂质堆积情况，且呈现剂量依赖性，而半乳糖醛酸（GalA）的存在可能是其抑制HepG2细胞脂质蓄积的关键因素。     

Fungal mycobiome drives IL-33 secretion and type 2 immunity in pancreatic cancer

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Interrelationships between Cellular Density,Mosaic Patterning,and Dendritic Coverage of VGluT3 Amacrine Cells

Amacrine cells of the retina are conspicuously variable in their morphologies, their population demographics, and their ensuing functions. Vesicular glutamate transporter 3 (VGluT3) amacrine cells are a recently characterized type of amacrine cell exhibiting local dendritic autonomy. The present analysis has examined three features of this VGluT3 population, including their density, local distribution, and dendritic spread, to discern the extent to which these are interrelated, using male and female mice. We first demonstrate that Bax-mediated cell death transforms the mosaic of VGluT3 cells from a random distribution into a regular mosaic. We subsequently examine the relationship between cell density and mosaic regularity across recombinant inbred strains of mice, finding that, although both traits vary across the strains, they exhibit minimal covariation. Other genetic determinants must therefore contribute independently to final cell number and to mosaic order. Using a conditional KO approach, we further demonstrate that Bax acts via the bipolar cell population, rather than cell-intrinsically, to control VGluT3 cell number. Finally, we consider the relationship between the dendritic arbors of single VGluT3 cells and the distribution of their homotypic neighbors. Dendritic field area was found to be independent of Voronoi domain area, while dendritic coverage of single cells was not conserved, simply increasing with the size of the dendritic field. Bax-KO retinas exhibited a threefold increase in dendritic coverage. Each cell, however, contributed less dendrites at each depth within the plexus, intermingling their processes with those of neighboring cells to approximate a constant volumetric density, yielding a uniformity in process coverage across the population.SIGNIFICANCE STATEMENT Different types of retinal neuron spread their processes across the surface of the retina to achieve a degree of dendritic coverage that is characteristic of each type. Many of these types achieve a constant coverage by varying their dendritic field area inversely with the local density of like-type neighbors. Here we report a population of retinal amacrine cells that do not develop dendritic arbors in relation to the spatial positioning of such homotypic neighbors; rather, this cell type modulates the extent of its dendritic branching when faced with a variable number of overlapping dendritic fields to approximate a uniformity in dendritic density across the retina.     

Inhibition of autophagy enhances apoptosis induced by bortezomib in AML cells

Bortezomib is a novel proteasome inhibitor, which has been successfully used to treat mantle cell lymphoma and multiple myeloma. However, the direct effects of bortezomib on acute promyelocytic leukaemia (APL) have not been fully investigated. In the present study, the WST-8 assay, western blotting, flow cytometry, monodansylcadaverine staining and transmission electron microscopy were performed. It was demonstrated that bortezomib treatment induced a time- and dose-dependent decrease in the viability of NB4 cells. Bortezomib treatment induced cell apoptosis in NB4 cells, as assessed by Annexin V/propidium iodide analysis, and the detection of cleaved caspase-3, cleaved poly(ADP-ribose) polymerase, Bax and Bcl-2 expression. Furthermore, bortezomib treatment induced autophagy in NB4 cells, as indicated by autophagosome formation, p62 degradation, LC3-I to LC3-II conversion and formation of acidic autophagic vacuoles. Notably, autophagy induced by bortezomib was initiated prior to apoptosis. Inhibition of autophagy by knocking down Beclin-1 expression increased bortezomib-induced apoptosis in NB4 cells. Therefore, the present study revealed that the combination of bortezomib and autophagy inhibition may be a potential treatment strategy for APL.     

Influences of simulated gastrointestinal environment on physicochemical properties of gold nanoparticles and their implications on intestinal epithelial permeability

Gold nanoparticles (Au NPs) hold great promise in food, industrial and biomedical applications due to their unique physicochemical properties. However, influences of the gastrointestinal tract (GIT), a likely route for Au NPs administration, on the physicochemical properties of Au NPs has been rarely evaluated. Here, we investigated the influence of GIT fluids on the physicochemical properties of Au NPs (5, 50, and 100?nm) and their implications on intestinal epithelial permeability in vitro. Au NPs aggregated in fasted gastric fluids and generated hydroxyl radicals in the presence of H₂O₂. Cell studies showed that GIT fluids incubation of Au NPs affected the cellular uptake of Au NPs but did not induce cytotoxicity or disturb the intestinal epithelial permeability.     

A novel PAX6 mutation causes congenital aniridia with or without retinal detachment

Background: Aniridia is a rare developmental eye disorder characterized by complete or partial iris hypoplasia often accompanied with other ocular changes that affect the cornea, anterior chamber, lens, retina, and optic nerve. Most cases of aniridia are inherited with an autosomal dominant mode of inheritance caused by PAX6 mutations or deletions. To reveal the underlying genetic defect in a four-generation Iranian family with aniridia, we carried out a genetic screening of PAX6.

Methods: Complete ophthalmic examinations were performed for available affected family members. All PAX6 exons and their flanking regions were sequenced for affected individuals. Candidate variation was screened for segregation in the pedigree by Sanger sequencing. Bioinformatics prediction was done to evaluate the deleterious effects of the mutation on protein product. Real-time PCR was used to investigate the impact of the variant on PAX6 mRNA expression.

Results: All patients were diagnosed with isolated aniridia associated with variable phenotypic features including retinal detachment. A novel heterozygous deletion c.320_348delTGTCCGAGGGGGTCTGTACCAACGATAAC (p.Leu107HisfsX16) on PAX6 gene was detected. Decreased mRNA level of PAX6 in the affected individuals indicated that the mutation caused nonsense-mediated mRNA decay (NMD).

Conclusions: To the best of our knowledge, it is the first report on the genetics of aniridia in Iran. Segregation analysis, bioinformatics prediction and confirmation of NMD, all support the proposition that the novel observed PAX6 mutation is the cause of aniridia in the pedigree. Retinal detachment in some of the affected members, which is a rare reported phenotypic feature of aniridia patients, may be associated with this mutation.     

Assessment of oral ciprofloxacin impaired gut barrier integrity on gut bacteria in mice

Gut bacteria and gut barrier plays important roles in body homeostasis. Ciprofloxacin (CPFX) is widely used to treat bacterial infections. However, whether high dosage of CPFX has side effects on gut barrier integrity is still unclear. Our results indicated that the High CPFX treatment (1 mg/ml) caused weight loss, nervousness, anorexia, and increased apoptosis cells in gut, but less influence was observed in the Low CPFX group (0.2 mg/ml). Meanwhile, the High CPFX treatment impaired tight junction molecules Ocln/ZO-1 level and down-regulated antibacterial genes expression (reg3γ, pla2g2α and defb1). Further, the High CPFX treatment increased pro-inflammatory cytokine IL-1β in intestinal tract, decreased IL-17A of duodenum but increased IL-17A of colon at day 37. In addition, the gut bacterial diversity and richness behaved significantly loss regarding CPFX treatment, especially in the High CPFX group during the experiment. Indole exhibited sharply decline in both Low and High CPFX groups at day 7, and the High CPFX mice needed longer time on restoring indole level. Meanwhile, CPFX treatment strongly decreased the concentrations of butyric acid and valeric acid at day 1. Correlation analysis indicated that the linked patterns between the key bacteria (families Bacteroidales_S247, Ruminococcaceae and Desulfovibrionaceae) and metabolites (indole and butyric acid) were disturbed via the CPFX treatment. In conclusion, the High CPFX treatment impaired the gut barrier with the evidence of reduced expression of tight junction proteins, increased apoptosis cells and inflammatory cells, decreased the bacterial diversity and composition, which suggesting a proper antibiotic-dosage use should be carefully considered in disease treatment.