By Yune- Fang Ueng, Published on 06/15/20

By Yune- Fang Ueng, Published on 06/15/20

High-fat food intake is the main source of dioxin-like compounds for humans, such as consumption of meat, dairy and eggs, and seafood products. Fruits, vegetables, and cereals have relatively low levels of dioxin-like compounds, but because of high consumption they also contribute to the food-borne intake. It is necessary to clarify dietary dioxin exposure affected by different food contamination levels and dietary habits among different geographic areas. We aimed to evaluate chronic dietary PCDD/Fs and DL-PCBs exposure in 725 individual foods in 14 categories in 6 Taiwan air quality regions (AQRs) and a total of 2,441 foods from 2004 and 2018. We estimated daily PCDD/Fs+DL-PCBs intake on the basis of sex- and age-specific foodstuff ingestion rate and PCDD/Fs+DL-PCBs concentrations using a probabilistic approach. PCDD/F+DL-PCB levels among the different sampling periods exhibited a decreasing trend in fish and aquatic products (from 0.384± 0.764 to 0.206± 0.223 pg WHO05-TEQ g-1 w.w.)(p for trend= 0.043), livestock products (from 0.133± 0.298 to 0.035± 0.043pg WHO05-TEQ g-1 w.w.), eggs (from 0.221± 0.373 to 0.056± 0.048pg WHO05-TEQ g-1 w.w.) (p for trend= 0.002), and dairy samples (from 0.066± 0.075 to 0.024± 0.026pg WHO05-TEQ g-1 w.w.) (p for trend= 0.001). All lifetime average daily doses (LADD) were below provisional tolerable monthly intake (PTMI) but higher than the TWI for PCDD/Fs and DL-PCBs in food. The percentages of the contribution of each food group to the total dietary intake of TEQPCDD/F+PCB in different ambient air dispersion areas and age groups. The total daily intake of PCDD/Fs and DL-PCBs by Taiwanese differed between AQRs (0.188 to 0.397 pg WHO05-TEQ kg-1 b.w. day-1). The observed geographical variations were likely due to differences in food habits, cuisines, culture and levels of environmental contamination among various regions in Taiwan. By sensitivity analysis, we have identified the major contribution to LADD, which was the dioxin levels in marine fish, freshwater fish and fish related products, and followed by dioxin levels in duck eggs. In addition, marine and freshwater fish consumption rate accounts more than 10.2%. These major exposure variables was also consistent with the findings of total daily intake in different AQRs.

Platycodin D (PD) has been used as the quality control marker of Radix Platycodonis for its high content and various pharmacological properties. In this study, a specific polyclonal antibody against PD (PD–pAb) was developed, and PD–pAb-based indirect competitive enzyme-linked immunosorbent assay (icELISA) was established for the detection of PD in Radix Platycodonis. The 50% inhibition concentration (IC50) of PD was 2.70 μg/mL and the linearity range for PD was from 0.064 μg/mL to 100 μg/mL. No cross reactivity with PD–pAb was found in five PD analogs except for PD2 (0.93%). The average recovery of PD by icELISA was 97.14% (RSD = 1.17%). There was a good correlation (r = 0.9654) between the PD contents in Radix Platycodonis detected by icELISA and high performance liquid chromatography (HPLC). Taken together, the established icELISA might be a sensitive, specific, simple, cheap and high-throughput method for determining the contents of PD in Radix Platycodonis.

Acarbose (an a-glucosidase inhibitor) has been demonstrated to reduce the progression of atherosclerosis without affecting serum levels of glucose in rabbits fed a high cholesterol diet. The main focus of recent atherosclerosis studies has been microRNA targets. However, the mechanism by which acarbose targets miRNA-mediated atherosclerosis remains unclear. This study aimed to evaluate the effect of acarbose on microRNA-related regulation of rat aortic vascular smooth cell line (A7r5 cell) migration and proliferation induced by diabetic conditions. We reported that acabose exhibit significantly inhibits proliferative and cell migration abilities in A7r5 cells. The expression of protein and levels of mRNA were measured by Western blot analysis and real-time PCR. Acarbose inhibited the phosphorylation of focal adhesion kinase (FAK) and phosphoinositide 3-kinases (PI3K)/protein kinase B (Akt), Ras signals, small GTPase proteins expression to attenuate cell migration and proliferation. Furthermore, acarbose upregulated the expression of miR143, and transfected miR-143 mimic and its inhibitor to explore its mechanism. In conclusion, acarbose reduces VSMC migration and proliferation via upregulating miR-143 to inhibit Ras-related signaling, and potentially prevention of atherosclerosis.

By Yune- Fang Ueng, Published on 06/15/20

By Farnaz Monajjemzadeh, Published on 06/15/20

We demonstrated a sensitive electrochemical method for the determination of non-electroactive melamine (Mel) using a modified glassy carbon electrode (GCE), with uric acid (UA) as the signal reporter. To increase the anodic response of UA, GCE was coated with Au–Ag nanoparticles and a Nafion thin film (Au–Ag/Nafion/GCE). The sensing mechanism was based on the competitive adsorption behavior of Mel on the Au–Ag/Nafion/GCE, which reduces the electroactive surface area of nanoparticles and thus hinders anodic response of UA. Under optimal conditions and the use of an analytical method of differential pulse voltammetry, this modified electrode detected Mel concentrations ranging from 2.5 to 70 nM, with a detection limit of 1.8 nM. The Au–Ag/Nafion/GCE demonstrated satisfactory reproducibility and stability, with relative standard deviations (RSDs) of 9.3% and 7.1%, respectively. The proposed electrochemical method was then successfully used to determine the Mel content in spiked milk powder and cat food samples, with RSDs of 1.7%–9.3% and recoveries of 92.4%–103.7%.

Nucleotides are composed of nitrogen bases, ribose units and phosphate groups. Adenine (Ade), adenosine monophosphate (AMP), adenosine diphosphate (ADP) and adenosine triphosphate (ATP) all play important roles in physiological metabolism. Royal jelly, a secretion produced by worker bees, contains a variety of natural ingredients and several studies have shown that royal jelly can serve as a source of nutrition for humans. In this study, a rapid and effective LC/MS method coupled with pre-processing methods was developed and validated for the accurate quantification of Ade, AMP, ADP and ATP in royal jelly. To achieve the best extraction efficiency, two pretreatment methods, namely, solid-phase extraction (SPE) and dispersive solid-phase extraction (dSPE), were developed and investigated. Silica-based cyanopropyl (CN) liquid chromatography was employed using pH programming with a quaternary mobile phase system for the analyses. The total LC/MS run time was less than 12 min with a constant flow rate of 0.25 mL/min. The linear range were 2.5-1000 ng/mL with a correlation coefficient r = 0.9995. The limit of detection (LOD) and limit of quantitation (LOQ) of the method was 1.0 ng/mL and 2.5 ng/mL, respectively. The limit of detection (LOD) of Ade, AMP, ADP and ATP was 1, 1, 2.5 and 5 ng/mL; the limit of quantitation (LOQ) was 2.5, 2.5, 5 and 10 ng/mL, respectively. Precision (RSD%

Hyperthyroidism is a common endocrine disorder associated with increased risk of cardiovascular complications and mortality. Although antithyroid drugs (ATDs) are approved as first line option for many hyperthyroidism cases, including pregnancy and childhood, they exert significant toxic profile. Medicago sativa L. (alfalfa) also called “The father of all food” was among the diet consumed by mares that gave birth to foals with congenital hypothyroidism. Since, greenfeed was accused for the development of such condition, alfalfa may possess constituents with promising antithyroid potential that could be a valuable substitute for the conventional ATDs. The current work was designed to identify the most biologically active antithyroid phytoconstituent separated from alfalfa sprouts and comparing its antithyroid mechanism, efficacy and toxic profile to the standard ATD; propylthiouracil (PTU). The most biologically active solvent fractions from alfalfa sprouts extract were identified by in vitro screening for anti-thyroid peroxidase (TPO) activity, from which different phytoconstituents were separated and identified by interpretation of spectroscopic data. These compounds were then in vitro screened for anti-TPO and virtually screened via GLIDE XP docking into the crystal structures of the enzymes; bovine lactoperoxidase, as an alternative to TPO, and mammalian selenocysteine-dependent iodothyronine deiodinase (IDI), that are both uniquely dually prohibited by PTU. The compound that showed the least TPO IC50 and highest combined docking XP score was elected for comparing its antithyroid mechanism, efficacy, tendency to reverse hyperthyroidism-triggered complications and toxicity to PTU using L-thyroxine-induced hyperthyroidism model in rats. Seven compounds (1-7) were isolated from the most biologically active fraction, whilst, compounds (4-7) were reported for the first time from alfalfa sprouts. Compound 5 (apigenin) showed the least TPO IC50 and highest in-silico combined score, thus, apigenin was selected for further in-vivo investigations. Apigenin was found to more effectively interfere with type 1-IDI than with TPO in vivo. Apigenin therapy resulted in nearly euthyroid state, without incidence of hypothyroidism, thyroid hypertrophy, hepatotoxity or WBCs count reduction. In addition, apigenin, but not PTU, corrected hyperthyroidism-induced left ventricular hypertyrophy. Therefore, apigenin is a natural lead antithyroid drug that represents a possible safer alternative to conventional ATDs