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.     

HPLC-MS/MS测定连翘中连翘酯苷A、阿魏酸、槲皮素、松脂醇β-D葡萄糖苷、连翘苷的含量

[目的]建立采用HPLC-MS/MS测定连翘中连翘酯苷A、阿魏酸、槲皮素、松脂醇β-D葡萄糖苷、连翘苷的含量的方法,为其开发应用提供方法参考。[方法]色谱柱选用Phenomenex Luna C18柱(150 mm×2. 0 mm,5μm);流动相A:0. 1%甲酸溶液,流动相B:100%乙腈;流速为0. 7 m L/min;进样量为12μL;洗脱梯度设定为:0～5 min,10%～55%B; 5～11 min,55%～100%B。质谱选择负离子扫描,离子源为电喷雾式(ESI)。采用多反应监测的检测模式,喷雾电压:-4. 7 k V,雾化气压0. 5 MPa,雾化温度620℃,氮气压力0. 65 MPa。[结果]本次研究所检测的连翘在可测定浓度的范围内5种成分的峰面积与浓度都表现出较好的线性关系,加样后的回收率在97. 8%～99. 5%之间。[结论]采用HPLC-MS/MS测定连翘中5中成分的含量效果较好,灵敏度高、结果可靠,为连翘的开发应用以及质量控制提供了参考。     

健脾益肾方对非小细胞肺癌细胞体外增殖凋亡作用的实验研究

目的:探讨健脾益肾方对非小细胞肺癌(NSCLC)细胞体外增殖凋亡的作用。方法:人NSCLC细胞系A549分为四组:空白对照组(仅加入细胞培养液)、阴性对照组(加入细胞,不进行中药处理)、实验组(加细胞加中药处理)。荧光定量PCR和Western blot分别检测Survivin、Bcl-2和Caspase-3的mRNA和蛋白表达。MTT检测细胞增殖;流式细胞术检测细胞凋亡。结果:与空白对照组相比,阴性对照组细胞在24、48、72 h的吸光度值明显升高,细胞凋亡率下降,Survivin和Bcl-2 mRNA和蛋白相对表达量上调,Caspase-3 mRNA和蛋白相对表达量下调,组间比较差异有统计学意义(P<0.05);而健脾益肾方处理的实验组24、48、72 h的吸光度值均显著降低,细胞凋亡率显著上升,Survivin和Bcl-2 mRNA和蛋白相对表达量下调,Caspase-3 mRNA和蛋白相对表达量上调,与空白对照组相比差异有统计学意义(P<0.05)。结论:健脾益肾方可通过下调Survivin和Bcl-2、上调Caspase-3表达诱导NSCLC细胞凋亡,并抑制肿瘤细胞的增殖,进而抑制NSCLC的发展。     

Marmoset cytochrome P450 2B6, a propofol hydroxylase expressed in liver

1. The common marmoset (Callithrix jacchus) is a useful experimental animal to evaluate the pharmacokinetics of drug candidates. Cytochrome P450 (P450) 2B enzyme in marmoset livers has been identified; however, only limited information on the enzymatic properties and distribution has been available.

2. Marmoset P450 2B6 amino acids showed high sequence identities (>86%) with those of primates including humans and cynomolgus monkeys. Phylogenetic analysis using amino acid sequences indicated that marmoset P450 2B6 was closer to human and cynomolgus monkey P450 2B6 than to P450 2B orthologs of other species, including pigs, dogs, rabbits and rodents.

3. Quantitative polymerase chain reaction analysis using specific primers showed P450 2B6 mRNA predominantly expressed in livers among the five marmoset tissues, similar to those of humans and cynomolgus monkeys.

4. Marmoset P450 2B6 heterologously expressed in Escherichia coli membranes oxidized 7-ethoxycoumarin, pentoxyresorufin, propofol and testosterone, at roughly similar rates to those of humans and/or cynomolgus monkeys. A high capacity of marmoset P450 2B6 with propofol 4-hydroxylation (at low ionic strength conditions) with a low K_m value was relatively comparable to that for marmoset livers.

5. These results collectively indicated a high propofol 4-hydroxylation activity of P450 2B6 expressed in marmoset livers.

     

Solid‐type poorly differentiated adenocarcinoma of the stomach: Deficiency of mismatch repair and SWI/SNF complex

ARID1A, one of the subunits in SWI/SNF chromatin remodeling complex, is frequently mutated in gastric cancers with microsatellite instability (MSI). The most frequent MSI in solid‐type poorly differentiated adenocarcinoma (PDA) has been reported, but the SWI/SNF complex status in solid‐type PDA is still largely unknown. We retrospectively analyzed 54 cases of solid‐type PDA for the expressions of mismatch repair (MMR) proteins (MLH1, PMS2, MSH2, and MSH6), SWI/SNF complex subunits (ARID1A, INI1, BRG1, BRM, BAF155, and BAF170) and EBER, and mutations in KRAS and BRAF. We analyzed 40 cases of another histological type of gastric cancer as a control group. The solid‐type PDAs showed coexisting glandular components (76%), MMR deficiency (39%), and complete/partial loss of ARID1A (31%/7%), INI1 (4%/4%), BRG1 (48%/30%), BRM (33%/33%), BAF155 (13%/41%), and BAF170 (6%/2%), EBER positivity (4%), KRAS mutation (2%), and BRAF mutation (2%). Compared to the control group, MMR deficiency and losses of ARID1A, BRG1, BRM, and BAF155 were significantly frequent in solid‐type PDAs. Mismatch repair deficiency was associated with the losses of ARID1A, BRG1, and BAF155 in solid‐type PDAs. In the MMR‐deficient group, solid components showed significantly more frequent losses of ARID1A, BRG1, BRM, and BAF155 compared to glandular components (P = .0268, P = .0181, P = .0224, and P = .0071, respectively). In the MMR‐proficient group, solid components showed significantly more frequent loss of BRG1 compared to glandular components (P = .012). In conclusion, solid‐type PDAs showed frequent losses of MMR proteins and the SWI/SNF complex. We suggest that loss of the SWI/SNF complex could induce a morphological shift from differentiated‐type adenocarcinoma to solid‐type PDA.     

Ginsenoside Rg1 prevents acetaminophen-induced oxidative stress and apoptosis via Nrf2/ARE signaling pathway

Inappropriate use of acetaminophen (APAP) can lead to morbidity and mortality secondary to hepatic necrosis. Ginsenoside Rg1 is a major active ingredient in processed Panax ginseng, which is proved to elicit biological effects. We hypothesized the beneficial effect of Rg1 on APAP-mediated hepatotoxicity was through Nrf2/ARE pathway. The study was conducted in cells and mice, comparing the actions of Rg1. Rg1 significantly improved cell survival rates and promoted the expression of antioxidant proteins. Meanwhile, Rg1 reduced the excessive ROS and the occurrence of cell apoptosis, which were related to Nrf2/ARE pathway. Expression of Nrf2 has a certain cell specificity.

     

Efficacy of istradefylline for gait disorders with freezing of gait in Parkinson’s disease: A single-arm,open-label,prospective, multicenter study

Background: Gait disorders are common in Parkinson’s disease patients who respond poorly to dopaminergic treatment. Blockade of adenosine A_2A receptors is expected to improve gait disorders. Istradefylline is a first-in-class selective adenosine A_2A receptor antagonist with benefits for motor complications associated with Parkinson’s disease.

Research design and methods: This multicenter, open-label, single-group, prospective interventional study evaluated changes in total gait-related scores of the Part II/III Movement Disorder Society-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) and Freezing of Gait Questionnaire (FOG-Q) in 31 Parkinson’s disease patients treated with istradefylline. Gait analysis by portable gait rhythmogram was performed.

Results: MDS-UPDRS Part III gait-related total scores significantly decreased at Weeks 4–12 from baseline with significant improvements in gait, freezing of gait, and postural stability. Significant decreases in MDS-UPDRS Part II total scores and individual item scores at Week 12 indicated improved daily living activities. At Week 12, there were significant improvements in FOG-Q, new FOG-Q, and overall movement per 48 h measured by portable gait rhythmogram. Adverse events occurred in 7/31 patients.

Conclusions: Istradefylline improved gait disorders in Parkinson’s disease patients complicated with freezing of gait, improving their quality of life. No unexpected adverse drug reactions were identified.

Trial registration: UMIN-CTR (UMIN000020288).