LC–MS quantification of parthenolide and cholinesterase inhibitory potential of selected Tanacetum L. (Emend. Briq.) taxa

The acetonitrile extracts of various Tanacetum L. (Emend. Briq.) taxa from Turkey as well as parthenolide, a sesquiterpene lactone found in Tanacetum species as active substance were investigated for their inhibitory activity against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), the key enzymes in pathogenesis of Alzheimer's disease, at 100 μg mL⁻¹ using ELISA microplate assay. Most of the extracts displayed a remarkable AChE inhibition where the leaf of Tanacetum argenteum subsp. flabellifolium had the highest inhibition (96.68 ± 0.35%). The extracts had moderate inhibition toward BChE, among which the stem of Tanacetum argyrophyllum var. argyrophyllum-1 exerted the best inhibition (63.81 ± 3.64%). However, parthenolide exhibited low inhibition against both of the enzymes. Total flavonoid content of the extracts was determined spectrophotometrically. Parthenolide, a sesquiterpene lactone, was quantified in these taxa by LC–MS and the leaf of T. argenteum subsp. argenteum possessed the richest parthenolide amount (2.261 ± 0.002%), while most of the species screened were found to contain the required percentage (0.2% minimum) by European Pharmacopeia.     

Dual blockade of the A1 and A2A adenosine receptor prevents amyloid beta toxicity in neuroblastoma cells exposed to aluminum chloride

In a previous work we have shown that exposure to aluminum (Al) chloride (AlCl₃) enhanced the neurotoxicity of the amyloid beta_25-35 fragment (Abeta_25-35) in neuroblastoma cells and affected the expression of Alzheimer's disease (AD)-related genes. Caffein, a compound endowed with beneficial effects against AD, exerts neuroprotection primarily through its antagonist activity on A_2A adenosine receptors (A_2AR), although it also inhibits A₁Rs with similar potency. Still, studies on the specific involvement of these receptors in neuroprotection in a model of combined neurotoxicity (Abeta_25-35 + AlCl₃) are missing. To address this issue, cultured SH-SY5Y cells exposed to Abeta_25-35 + AlCl₃ were assessed for cell viability, morphology, intracellular ROS activity and expression of apoptosis-, stress- and AD-related proteins. To define the role of A₁R and A_2ARs, pretreatment with caffein, specific receptor antagonists (DPCPX or SCH58261) or siRNA-mediated gene knockdown were delivered. Results indicate that AlCl₃ treatment exacerbated Abeta_25-35 toxicity, increased ROS production, lipid peroxidation, β-secretase-1 (BACE1) and amyloid precursor protein (APP). Interestingly, SCH58261 successfully prevented toxicity associated to Abeta_25-35 only, whereas pretreatment with both DPCPX and SCH58261 was required to fully avert Abeta_25-35 + AlCl₃-induced damage, suggesting that A₁Rs might also be critically involved in protection during combined toxicity. The effects of caffein were mimicked by both N-acetyl cysteine, an antioxidant, and desferrioxamine, likely acting through distinct mechanisms. Altogether, our data establish a novel protective function associated with A₁R inhibition in the setting of combined Abeta_25-35 + AlCl₃ neurotoxicity, and expand our current knowledge on the potential beneficial role of caffein to prevent AD progression in subjects environmentally exposed to aluminum.     

Acetylcholinesterase inhibitors and compounds promoting SIRT1 expression from Curcuma xanthorrhiza

Curcuma xanthorrhiza is a well-known traditional medicine with anti-inflammatory and anticancer activities, as well as protective effects against neurodegenerative disorders. A previous study revealed the acetylcholinesterase (AChE) inhibitory activity of some sesquiterpenoids from C. xanthorrhiza. In this study, further bioassay-guided isolation led to the identification of nine compounds for the first time from C. xanthorrhiza, including a new Guaiane-type sesquiterpene, zedoaraldehyde (1). Their structures were elucidated using NMR and MS techniques. The AChE inhibitory activities of compounds 1, 3, 4 and 7 were detected as minimum inhibitory quantities of 3, 4, 6 and 1 μg, respectively, using a TLC bioautography assay. Meanwhile, compounds 1, 3, 4 and 8 could promote SIRT1 expression by 1.37-, 1.71-, 1.73- and 1.27-fold, respectively, in HEK293 cell lines exposed to compounds at a concentration of 20 μM for 24 h. SIRT1 is becoming an important drug target for new therapies in the treatment of neurodegenerative diseases. This study indicates the potential of sesquiterpenoids from C. xanthorrhiza for use against Alzheimer's disease.     

Design,synthesis, and X-ray structural studies of BACE-1 inhibitors containing substituted 2-oxopiperazines as P1′-P2′ ligands

We report the design and synthesis of a series of BACE1 inhibitors incorporating mono- and bicyclic 6-substituted 2-oxopiperazines as novel P1′ and P2′ ligands and isophthalamide derivative as P2-P3 ligands. Among mono-substituted 2-oxopiperazines, inhibitor 5a with N-benzyl-2-oxopiperazine and isophthalamide showed potent BACE1 inhibitory activity (K_i = 2 nM). Inhibitor 5g, with N-benzyl-2-oxopiperazine and substituted indole-derived P2-ligand showed a reduction in potency. The X-ray crystal structure of 5g-bound BACE1 was determined and used to design a set of disubstituted 2-oxopiperazines and bicyclic derivatives that were subsequently investigated. Inhibitor 6j with an oxazolidinone derivative showed a BACE1 inhibitory activity of 23 nM and cellular EC₅₀ of 80 nM.     

Zinc transporter gene expression and glycemic control in post-menopausal women with Type 2 diabetes mellitus

Type 2 diabetes mellitus (DM) is associated often with underlying zinc deficiency and nutritional supplements such as zinc may be of therapeutic benefit in the disease. In a randomized, double-blind, placebo-controlled, 12-week trial in postmenopausal women (n = 48) with Type 2 DM we investigated the effects of supplementation with zinc (40 mg/d) and flaxseed oil (FSO; 2 g/d) on the gene expression of zinc transporters (ZnT1, ZnT5, ZnT6, ZnT7, ZnT8, Zip1, Zip3, Zip7, and Zip10) and metallothionein (MT-1A, and MT-2A), and markers of glycemic control (glucose, insulin, glycosylated hemoglobin [HbA1c]). The homeostasis model assessment of insulin resistance (HOMA-IR) was calculated. No significant effects of zinc or FSO supplementation were observed on glycemic marker concentrations, HOMA-IR or fold change over 12 weeks in zinc transporter and metallothionein gene expression. In multivariate analysis, the change over 12 weeks in serum glucose concentrations (P = 0.001) and HOMA-IR (P = 0.001) predicted the fold change in Zip10. In secondary analysis, marginal statistical significance was observed with the change in both serum glucose concentrations (P = 0.003) and HOMA-IR (P = 0.007) being predictive of the fold change in ZnT6. ZnT8 mRNA expression was variable; HbA1c levels were higher (P = 0.006) in participants who exhibited ZnT8 expression compared to those who did not. The significant predictive relationships between Zip10, ZnT6, serum glucose and HOMA-IR are preliminary, as is the relationship between HbA1c and ZnT8; nevertheless the observations support an association between Type 2 DM and zinc homeostasis that requires further exploration.     

Selenium status in elderly: Relation to cognitive decline

Studies show that decreased antioxidant system is related to cognitive decline. Thus we aimed to measure selenium (Se) status in Alzheimer's disease (AD) and mild cognitive impairment (MCI) elderly and compared them with a control group (CG). 27 AD, 17 MCI and 28 control elderly were evaluated. Se concentration was determined in plasma and erythrocyte by using hydride generation atomic absorption spectroscopy. Erythrocyte Se concentration in AD group was lower than CG (43.73 ± 23.02 μg/L and 79.15 ± 46.37 μg/L; p = 0.001), but not statistically different from MCI group (63.97 ± 18.26 μg/L; p = 0.156). AD group exhibited the lowest plasma Se level (34.49 ± 19.94 μg/L) when compared to MCI (61.36 ± 16.08 μg/L; p = 0.000) and to CG (50.99 ± 21.06 μg/L; p = 0.010). It is observed that erythrocyte Se decreases as cognition function does. Since erythrocyte reflects longer-term nutritional status, the data point to the importance of the relation between Se exposure and cognitive function. Our findings suggest that the deficiency of Se may contribute to cognitive decline among aging people.     

A murine model of neonatal diabetes mellitus in Glis3-deficient mice

Glis3 is a member of the Gli-similar subfamily. GLIS3 mutations in humans lead to neonatal diabetes, hypothyroidism, and cystic kidney disease. We generated Glis3-deficient mice by gene-targeting. The Glis3^−/− mice had significant increases in the basal blood sugar level during the first few days after birth. The high levels of blood sugar are attributed to a decrease in the Insulin mRNA level in the pancreas that is caused by impaired islet development and the subsequent impairment of Insulin-producing cell formation. The pancreatic phenotypes indicate that the Glis3-deficient mice are a model for GLIS3 mutation and diabetes mellitus in humans.     

Genetic Variations of GWAS-Identified Genes and Neuroblastoma Susceptibility: a Replication Study in Southern Chinese Children

Neuroblastoma is one of the most commonly diagnosed solid cancers for children, and genetic factors may play a critical role in neuroblastoma development. Previous genome-wide association studies (GWASs) have identified nine genes associated with neuroblastoma susceptibility in Caucasians. To determine whether genetic variations in these genes are also associated with neuroblastoma susceptibility in Southern Chinese children, we genotyped 25 polymorphisms within these genes by the TaqMan method in 256 cases and 531 controls. Odds ratios (ORs) and 95% confidence intervals (CIs) were used to evaluate the strength of the associations. We performed a meta-analysis to further evaluate the associations. Furthermore, we calculated the area under the receiver-operating characteristic curves (AUC) to assess which gene/genes may better predict neuroblastoma risk. We confirmed that CASC15 rs6939340 A > G, rs4712653 T > C, rs9295536 C > A, LIN28B rs221634 A > T, and LMO1 rs110419 A > G were associated with significantly altered neuroblastoma susceptibility. We also confirmed that rs6939340 A > G (G versus A: OR = 1.30, 95% CI = 1.13-1.50) and rs110419 G > A (A versus G: OR = 1.37, 95% CI = 1.19-1.58) were associated with increased neuroblastoma risk for all subjects. We also found that the combination of polymorphisms in CASC15, LIN28B, and LMO1 may be used to predict neuroblastoma risk (AUC = 0.63, 95% CI = 0.59-0.67). Overall, we verified five GWAS-identified polymorphisms that were associated with neuroblastoma susceptibility alteration for Southern Chinese population; however, these results need further validation in studies with larger sample sizes.     

A cross-sectional survey among patients and prescribers on insulin dosing irregularities and impact of mild (self-treated) hypoglycemia episodes in Spanish patients with type 2 diabetes as compared to other European patients

Background and objectiveIn Spain, data suggest that 13.8% of adults have diabetes. Two important aspects in diabetes management are mild hypoglycemic episodes and poor treatment adherence. This study assesses the impact of missed insulin doses and prevalence of mistimed and reduced insulin doses and mild hypoglycemia in patients with type 2 diabetes treated with basal insulin analogues in Spain, and compares the data collected to pooled data from 8 other European countries (OECs).Materials and methodsGAPP2 was an international, online, cross-sectional study of diabetic patients aged ≥40 years treated with long-acting insulin analogues and their healthcare professionals. Patients and healthcare professionals were recruited from online research panels. Data reported in Spain are compared to pooled data from 8 OECs.ResultsIn Spain, 1–3% of patients reported they had reduced, missed, or mistimed at least one insulin does in the previous month. Significantly more OEC patients reported dosing irregularities (15–23%; all P < 0.01). In Spain, 77% of patients were worried and 59% felt guilty for missing a dose of basal insulin, while 24% reported that they were very worried about nocturnal hypoglycemia. Significantly fewer OEC patients reported worrying (47%; P < 0.01) and feeling guilty (37%; P < 0.01) about missing an insulin dose, or worry about nocturnal hypoglycemia (12%; P < 0.01).ConclusionsIn Spain, patients with type 2 diabetes report fewer dosing irregularities and hypoglycemic episodes as compared to patients from OECs. However, Spanish patients appear to have a reduced quality of life related to hypoglycemia as well as worry and guilt related to insulin dosing irregularities.     

FOXO 1a and FOXO 3a gene polymorphisms in association with metabolic syndrome

The prevalence and magnitude of childhood and adult obesity and diabetes are increasing dramatically. FOXO 1a and FOXO 3a will be evaluated in this study, in an effort to identify genetic polymorphisms in potential candidate genes that may be associated with body mass index (BMI), and metabolic syndrome (MS). Also to assess whether there is a relation between insulin sensitivity, and genotype, we will test the relation between fasting insulin, glucose, insulin resistance, insulin secretion and genotype.A total number of 248 presenting normal, overweight and obese individuals were recruited; 100 children and 148 adults of both sexes. They were divided by body mass index as follows, normal, overweight and obese. Lipid profile, fasting glucose and insulin HOMA-IR and HOMA-β index and RT-PCR for FOXO 1a and FOXO 3a were performed.An association was found among the studied group (children and adults) as regards foxo3a gene polymorphism and HOMA IR, HOMA B index and T-cholesterol (P = 0.022, 0.011 and 0.028, respectively), while there was only an association between LDL-C and foxo1a gene polymorphism among the studied group of children and adults (P = 0.023).In this study we demonstrated that FOXO3a mutant is correlated with HOMA-IR (marker of insulin resistance), HOMA-B index (marker of insulin secretion) and total cholesterol while as regards FOXO1a there was only an association between LDL cholesterol and mutant type of FOXO1a.     

Androgen metabolism and JAK/STAT pathway genes and prostate cancer risk

Background: Prostate cancer (PC) is the most frequently diagnosed solid tumor in U.S. men. Genome-wide association studies (GWAS) have identified over 40 risk-associated single nucleotide polymorphisms (SNPs), including variants in androgen pathway genes (e.g., KLK3 and AR). Androgens are important in PC and genes involved in this pathway are therefore candidates for conferring susceptibility to PC. Methods: In this hypothesis-testing study, we evaluated PC risk in association with SNPs in 22 candidate genes involved in androgen metabolism or interactions with the androgen receptor (AR). A total of 187 SNPs were genotyped in 1458 cases and 1351 age-matched controls from a population-based study. PC risk was estimated using adjusted unconditional logistic regression and multinomial regression models. Results: Single SNP analyses showed evidence (p < 0.05) for associations with 14 SNPs in 9 genes: NKX3.1, HSD17B3, AKR1C3, SULT2A1, CYP17A1, KLK3, JAK2, NCOA4 and STAT3. The most significant result was observed for rs2253502 in HSD17B3 (odds ratio, OR = 0.57, 95% CI: 0.39–0.84). In addition, five SNPs in four genes (CYP17A1, HSD17B4, NCOA4, and SULT2A1) were associated with more aggressive disease (p < 0.01). Conclusions: Our results replicate previously reported associations for SNPs in CYP17A1, HSD17B3, ARK1C3, NKX3.1, NCOA4 and KLK3. In addition, novel associations were observed for SNPs in JAK2, HSD17B4, and SULT2A1. These results will require replication in larger studies.     

Caulobacter zeae sp. nov. and Caulobacter radicis sp. nov., novel endophytic bacteria isolated from maize root (Zea mays L.)

Four bacterial strains designated 410^T, 441, 695^T and 736 were isolated from maize root in Beijing, P. R. China. Based on 16S rRNA gene phylogeny, the four strains formed two clusters in the genus Caulobacter. Since strain 441 was a clonal variety of strain 410^T, only three strains were selected for further taxonomic studies. The whole genome average nucleotide identity (ANI) value between strains 410^T and 695^T was 94.65%, and both strains shared less than 92.10% ANI values with their close phylogenetic neighbors Caulobacter vibrioides DSM 9893^T, Caulobacter segnis ATCC 21756^T and Caulobacter flavus CGMCC 1.15093^T. Strains 410^T and 695^T contained Q-10 as the sole ubiquinone and their major fatty acids were C_{16:0, 11-methyl C18:1ω 0}, 11-methyl C_{18: 1}ω7c, summed feature 3 (C_{16:1ω7c and/or C16:1ω 1}ω7c and/or C_{16: 1}ω6c) and summed feature 8 (C_{18:1ω7c and/or C18:1ω 1}ω7c and/or C_{18: 1}ω6c). Their major polar lipids consisted of glycolipids and phosphatidylglycerol, and phenotypic tests differentiated them from their closest phylogenetic neighbors. Based on the results obtained, it is proposed that the three strains represent two novel species, for which the names Caulobacter zeae sp. nov. (type strain 410^T = CGMCC 1.15991 = DSM 104304) and Caulobacter radicis sp. nov. (type strain 695^T = CGMCC 1.16556 = DSM 106792) are proposed.     

Synthesis of novel chromenones linked to 1,2,3-triazole ring system: Investigation of biological activities against Alzheimer’s disease

In this work, novel chromenones linked to 1,2,3-triazole ring system were synthesized and evaluated for their anti-ChE activity. Among them, N-((1-(2-chlorobenzyl)-1H-1,2,3-triazol-5-yl)methyl)-8-methoxy-2-oxo-2H-chromene-3-carboxamide (6m) showed good anti-acetylcholinesterase activity (IC₅₀ = 15.42 μM). Also, compound 6m demonstrated neuroprotective effect against H₂O₂-induced cell death in PC12 neurons, however, it showed no beta-secretase (BACE1) inhibitory activity. Docking and kinetic studies separately confirmed dual binding activity of compound 6m since it targeted both the catalytic active site (CAS) and the peripheral anionic site (PAS) of AChE.     

Induction Chemotherapy Has No Prognostic Value in Patients with Locoregionally Advanced Nasopharyngeal Carcinoma and Chronic Hepatitis B Infection in the IMRT Era

BACKGROUND: The effectiveness of induction chemotherapy (IC) followed by concurrent chemoradiotherapy (CCRT) over CCRT alone in patients with locoregionally advanced nasopharyngeal carcinoma (NPC) and chronic hepatitis B infection in the intensity-modulated radiotherapy (IMRT) era is unknown. PATIENTS AND METHODS: A total of 249 patients with stage T1-2 N2-3 or T3-4 N1-3 NPC and chronic hepatitis B infection treated with IMRT were retrospectively reviewed. Propensity score matching (PSM) was employed to balance covariates; 140 patients were propensity-matched (1:1 basis). Survival outcomes in the IC + CCRT and CCRT groups were compared using the Kaplan–Meier method, log-rank test and Cox proportional hazards model. RESULTS: No significant survival differences were observed between IC + CCRT and CCRT (5-year overall survival, 88.3% vs. 82.2%; P = .484; disease-free survival, 73.9% vs. 75.2%; P = .643; distant metastasis-free survival, 84.1% vs. 85.1%; P = .781; and locoregional failure-free survival, 87.9% vs. 85.1%; P = .834). After adjusting for known prognostic factors in multivariate analysis, IC was not an independent prognostic factor for any outcome (all P > .05); subgroup analysis based on T category (T1-2/T3-4), N category (N0-1/N2-3), and overall stage (III/IV) confirmed these results. The incidence of hepatic function damage in the IC + CCRT and CCRT groups was not significantly different. CONCLUSION: IC + CCRT leads to comparable survival outcomes and hepatic function damage compared to CCRT alone in patients with locoregionally advanced NPC with chronic hepatitis B infection in the IMRT era. Further investigations are warranted.     

Characterization of subventricular zone-derived progenitor cells from mild and late symptomatic YAC128 mouse model of Huntington's disease

Huntington's disease (HD) is caused by an expansion of CAG repeats in the HTT gene, leading to expression of mutant huntingtin (mHTT) and selective striatal neuronal loss, frequently associated with mitochondrial dysfunction and decreased support of brain-derived neurotrophic factor (BDNF). New neurons derived from the subventricular zone (SVZ) are apparently not able to rescue HD pathological features. Thus, we analyzed proliferation, migration and differentiation of adult SVZ-derived neural stem/progenitor cells (NSPC) from mild (6 month-old (mo)) and late (10 mo) symptomatic HD YAC128 mice expressing full-length (FL)-mHTT versus age-matched wild-type (WT) mice. SVZ cells derived from 6 mo YAC128 mice exhibited higher migratory capacity and a higher number of MAP2 + and synaptophysin + cells, compared to WT cells; MAP2 labeling was enhanced after exposure to BDNF. However, BDNF-evoked neuronal differentiation was not observed in 10 mo YAC128 SVZ-derived cells. Interestingly, 6 mo YAC128 SVZ-derived cells showed increased intracellular Ca²⁺ levels in response to KCl, which was potentiated by BDNF, evidencing the presence of differentiated neurons. In contrast, KCl depolarization-induced intracellular Ca²⁺ increase in 10 mo YAC128 SVZ-derived cells was shown to be increased only in BDNF-treated YAC128 SVZ-derived cells, suggestive of decreased differentiation capacity. In addition, BDNF-untreated NSPC from 10 mo YAC128 mice exhibited lower mitochondrial membrane potential and increased mitochondrial Ca²⁺ accumulation, in relation with NSPC from 6 mo YAC128 mice. Data evidence age-dependent reduced migration and decreased acquisition of a neuronal phenotype, accompanied by decreased mitochondrial membrane potential in SVZ-derived cells from YAC128 mice through HD symptomatic phases.