Protein Targets of Acetaminophen Covalent Binding in Rat and Mouse Liver Studied by LC-MS/MS.

Acetaminophen (APAP) is a mild analgesic and antipyretic used commonly worldwide. Although considered a safe and effective over-the-counter medication, it is also the leading cause of drug-induced acute liver failure. Its hepatotoxicity has been linked to the covalent binding of its reactive metabolite, N-acetyl p-benzoquinone imine (NAPQI), to proteins. The aim of this study was to identify APAP-protein targets in both rat and mouse liver, and to compare the results from both species, using bottom-up proteomics with data-dependent high resolution mass spectrometry and targeted multiple reaction monitoring (MRM) experiments. Livers from rats and mice, treated with APAP, were homogenized and digested by trypsin. Digests were then fractionated by mixed-mode solid-phase extraction prior to liquid chromatography-tandem mass spectrometry (LC-MS/MS). Targeted LC-MRM assays were optimized based on high-resolution MS/MS data from information-dependent acquisition (IDA) using control liver homogenates treated with a custom alkylating reagent yielding an isomeric modification to APAP on cysteine residues, to build a modified peptide database. A list of putative in vivo targets of APAP were screened from data-dependent high-resolution MS/MS analyses of liver digests, previous in vitro studies, as well as selected proteins from the target protein database (TPDB), an online resource compiling previous reports of APAP targets. Multiple protein targets in each species were found, while confirming modification sites. Several proteins were modified in both species, including ATP-citrate synthase, betaine-homocysteine S-methyltransferase 1, cytochrome P450 2C6/29, mitochondrial glutamine amidotransferase-like protein/ES1 protein homolog, glutamine synthetase, microsomal glutathione S-transferase 1, mitochondrial-processing peptidase, methanethiol oxidase, protein/nucleic acid deglycase DJ-1, triosephosphate isomerase and thioredoxin. The targeted method afforded better reproducibility for analysing these low-abundant modified peptides in highly complex samples compared to traditional data-dependent experiments.

Protective Effect of a Polyherbal Traditional Formula Consisting of Rosa damascena Mill., Glycyrrhiza glabra L. And Nardostachys jatamansi DC., Against Ethanol-induced Gastric Ulcer.

"VARD" formula consisting of Rosa damascena Mill. (Rosaceae) petals, and rhizomes of Glycyrrhiza glabra L. (Papilionaceae) and Nardostachys jatamansi DC. (Valerianaceae), has been proposed for gastric ulcer in Iranian traditional medicine. We investigated the antiulcer activity of each plant separately and in combination. The biochemical and molecular functions of extracts were also evaluated. Each plant hydroalcoholic extract was standardized via determination of total phenolic and flavonoid contents, also via some phenolic compounds determination and specially glycyrrhizic acid in G. glabra by using HPLC. Rats received orally extracts of the plants (20, 40 and 80 mg/Kg) and "VARD" (45 mg/Kg) 1 h before ethanol administration. Two h after receiving ethanol, animals were sacrificed; the stomach was removed for macroscopic and microscopic assessment. Also heme-oxygenase-1, glutathione, and catalase were measured in the gastric tissue of the rats pretreated by "VARD" and dose of 20 mg/Kg of extracts. Among three extracts, R. damascena and G. glabra contained more total phenolic and flavonoid content respectively. Gallic acid was prominent compound in R. damascena. The extracts of R. damascena, G. glabra, and N. jatamansi significantly decreased ulcer index. ED50 values were 8.2, 31.86 and 25.08 mg/Kg respectively. "VARD" significantly decreased ulcer index compared to 20 mg/Kg of G. glabra (p < 0.0001) and N. jatamansi (p < 0.001). Pretreatment with "VARD" and each plant extracts (20 mg/Kg) increased glutathione, catalse and heme-oxygenase-1 significantly (p < 0.05) in comparison with control group. Our findings indicate that "VARD" partly via antioxidant activity can be considered as an effective antiulcer formula.

Determination of eight synthetic dyes in foodstuffs by green liquid chromatography.

Eight synthetic food colours were analysed by green liquid chromatography. Green liquid chromatography is an environmentally friendly technique which does not use organic solvents in the extraction procedure or in the chromatographic method. Analysis was carried out for the following colours: tartrazine (E102), indigotine (E132), Quinoline Yellow (E104), Ponceau 4R (E124), Sunset Yellow (E110), Brilliant Blue (E133), Allura Red (E129) and carmoisine (E122) in four different foods: cookies, coloured rice, saffron and fruit juice. The method was performed on an Eurospher-100 C8 (5 µm, 4.6 × 250 mm) column with ultraviolet (UV)-VIS detection and validated by determining the calibration lines, measurement of recovery, precision, and limits of quantification and detection (LODs and LOQs). LOD ranged from 0.04 mg kg⁻¹ for E102 to 1.00 mg kg⁻¹ for E122; LOQ ranged from 0.06 mg kg⁻¹ for E102 to 1.12 mg kg⁻¹ for E122. The levels of colours in foods were compared with Iranian National Standards, but only 7.5% of cookies, 30% of coloured rice, 8% of saffron and 12% of juice samples were in compliance with these standards. Tartrazine is prohibited in Iran, but it was found as the most prevalent food colour in the samples analysed. The results of these tests confirmed that HPLC avoiding the use of organic solvents is a suitable method and can be used for quantitative analyses or screening of food samples for synthetic food colours.

Tocopherol content and Fatty Acid profile of different Iranian date seed oils.

Date is one of the world's oldest food-producing plants wich has always played an important role in the economy and social life. Various researchers examined chemical composition and nutritional values of edible parts of dates while limited information about chemical composition and nutritional quality of date seed is available. In this study, fatty acid composition and total tocopherol content of 14 Iranian date seed oils were studied. Statistical analysis was performed through SPSS computing package. According to the fatty acid profiles, seven fatty acids were found through nearly 50% oleic acid in seeds. Shekar cultivar by 51.40% had the maximum amount and Lasht cultivar by 33.38% had the minimum amount of oleic acid. Tocopherol content in the samples varied between 33.86 µg vit E/g oil for Shahabi2 to 10.09 µg vit E/g oil for Shekar. Tocopherol content was 1.88 and 0.61 µg respectively in one-gram seed of these two cultivars. Iranian date seed oils classified as oleic-lauric oil, had a high amount of oleic acid and could serve as a profitable source of valuable oils for industrial applications.

Plasma vitamin C concentrations in patients on routine hemodialysis and its relationship to patients' morbidity and mortality.

BACKGROUND: Some studies have hypothesized the protective role of vitamin C against cardiovascular disorders (CVD) in patients with end-stage renal disease (ESRD). This study was designed to assess plasma vitamin C concentration and its relationship to hemodialysis (HD) patients' morbidity and mortality. METHODS: Plasma vitamin C concentrations were assessed in HD patients using spectrophotometry and subjects were prospectively followed for up eighteen months for all-cause mortality. Any association between vitamin C concentration and patients' demographic data, co-morbidities, or the cause of ESRD were investigated using the Chi-square test. RESULTS: Ninety-one patients with a mean age of 56.7 ± 15.7 years were included in this study. The most frequent cause of ESRD was simultaneous hypertension and diabetes in 30 % of patients, followed by hypertension in 25.6 %, and diabetes in 11.1 %, respectively. About 34 % of patients had CVD as the most prevalent co-morbidity. Forty-nine patients (53.8 %) had low levels of vitamin C concentration. There was a significant relationship between vitamin C insufficiency and presence of any co-morbidity in HD patients (p < 0.05). There was a significant difference in vitamin C concentrations between patients without co-morbidities and those with cardiovascular ones (F[2,88]=3.447, p = 0.036). Twenty-two (24.2 %) patients died over a median duration of 227 days. There was a significant difference in time to death of patients with and without low levels of vitamin C concentration (p = 0.04). CONCLUSIONS: The results showed lower plasma vitamin C levels in HD patients who suffered any co-morbidity and sooner time to death in these patients.

The Relationship Between Vitamin E Plasma and BAL Concentrations, SOD Activity and Ventilatory Support Measures in Critically Ill Patients.

Vitamin E is a potent reactive oxygen metabolites (ROM) scavenger. It is a lipid-soluble vitamin and its main function is to protect polyunsaturated fatty acids against oxidative stress. Twenty-five mechanically ventilated Intensive Care Unit (ICU) adult patients participated in a prospective randomized clinical trial receiving either placebo (10 patients) or 3 IM doses (1000 IU each) of vitamin E (15 patients). We determined plasma and bronchoalveolar lavage (BAL) fluid concentrations of vitamin E and superoxide dismutase (SOD). Among these 25 patients, there were 14 men and 11 women, aged 63.16 ±15.48 years (mean ± SD; range = 33 to 87 years). Vitamin E supplementation resulted in significant differences in plasma and BAL vitamin E concentrations between the two groups (p-value = 0.01, 0.01), decrease in SOD activities (not differ significantly in plasma (p-value = 0.23)), but with significant differences in BAL (p-value = 0.016) and progressive reduction in Acute Physiology and Chronic Health Evaluation II (APACHE II) (p-value = 0.52) and Sequential Organ Failure Assessment (SOFA) (p-value = 0.008) score in vitamin E group. From the results of this study, it seems that supplementation of vitamin E as a potent antioxidant, along with other supportive measures, can be beneficial in decreasing SOD total activity, ROM production and risk of organ failure in critically ill patients.