Effects of liver S9 enzymes on somalargine and solasodine cytotoxicity and mass spectrometric fragmentation

The steroidal glycoalkaloid solamargine and its parent aglycone solasodine, isolated from Solanum palinacanthum, were studied in vitro for cytotoxicity and biotransformation by the hepatic S9 fraction as the metabolic activating system. The MTT uptake assay was used to determine viability after 24 h in RAW 264.7 mouse macrophage-like and SiHa cells exposed to various concentrations of the alkaloids in the presence and absence of the hepatic S9 microsomal fraction. The dose-response curves were established for solamargine and solasodine in the presence and absence of external metabolizing system. From these data, the cytotoxic index (CI50) was calculated with mean values of 7.2 and 13.6 μg/mL for Raw cells and 8.6 and 26.0 μg/mL for SiHa cells, respectively. Mass spectrometry was performed to compare the fragmentation patterns of the alkaloids to predict metabolism by the S9 fraction. The mass spectra demonstrated a distinct fragmentation patterns for solamargine and solasodine after the addition of the S9 fraction. In the present study, we demonstrate that the cytotoxic effect of solamargine and solasodine and their metabolites prepared in vitro by biotransformation with the S9 fraction are comparable. These findings suggest that the metabolic activation system S9 fraction may fail to suppress the cytotoxicity of these alkaloids. © 2013 Springer-Verlag Berlin Heidelberg.

Effects of propiogenic ingredients on serum concentration of insulin and progesterone in non-lactating cows

Three experiments evaluated serum insulin and progesterone (P4) concentrations in grazing Gir×Holstein cows supplemented with monensin (MON) or propylene glycol (PPG; 2.5mL/kg of live weight0.75 per drench). Cows were non-lactating, ovariectomized, and received an intravaginal drug-releasing device containing 1.9g of P4 to estimate treatment effects on hepatic P4 degradation. In Exp. 1, 15 cows received, in a crossover design containing 2 periods of 21d, 0.1kg/d of corn in addition to 2g/d of kaolin (CON) or 0.2g/d of MON. Blood samples were collected on d 13 and 20 of each period. Cows receiving CON had greater (P<0.05) serum insulin concentrations compared with MON prior to and 6h after feeding. However, MON cows had greater (P=0.01) serum P4 concentrations compared with CON 18h after feeding. In experiment 2, 15 cows received, in a replicated crossover design containing 2 periods of 24h, a single drench of PPG or water (WT). Cows receiving PPG had greater (P<0.01) serum insulin concentrations compared with WT from 0.5 to 3h after drench. However, PPG cows had reduced (P<0.05) serum P4 concentrations compared with WT at 1 and 2h after drench. In experiment 3, 13 cows received, in a replicated 3×3 Latin square design containing 3 periods of 24h, 3 PPG drenches administered 1h apart (PPG3x), 3 WT drenches administered 1h apart, or 1 PPG drench+2 WT drenches administered 1h apart (PPG1x). Serum insulin concentrations increased proportionally to PPG dosage (treatment×hour; P<0.01). However, mean serum P4 concentration was greater (P<0.01) in WT cows compared with PPG1x and PPG3x, but similar (P=0.25) between PPG1x and PPG3x cows. In conclusion, feeding propiogenic ingredients to grazing cows failed to substantially increase serum P4 concentrations. © 2013 Elsevier B.V.

Efeito de um protocolo de treinamento concorrente sobre fatores de risco para o acúmulo de gordura hepática de adolescentes obesos

Study Design: Prospective study Objective: To evaluate the effect of a protocol of concurrent training lasting 16 weeks on risk factors for the accumulation of hepatic fat in obese youth. Methods: 38 obese children and adolescents of both sexes, between 12 and 15 years old. The obesity was attested by the percentage of body fat, which was estimated by dual-energy X-ray absorptiometry (DEXA). Additionally, the amount of fat located in the trunk (kg) was estimated too. Before and after the intervention, the youths underwent biochemical blood tests (fasting complete lipid profile [mg / dL]) and ultrasonography of the liver (right size Wolves [LD cm] and left [LE in cm]). The intervention consisted of concurrent training (strength training [30 minutes] and endurance training [30 minutes]) with three sessions per week, totaling 180 minutes a week, for ten weeks. Statistical analysis was made by the test t of Student for paired data using SPSS software (17.0) and significance statistical fixed at p <5%. Results: After the intervention, significant improvements were observed in the percentage of total fat (PRE: 45.1 ± 5.3 and POST: 41.7 ± 5.6, p = 0.001) and in the trunk region (PRE: 46, 5 ± 5.6 and POST: 42.9 ± 6.3, p = 0.001). For lipid profile, reduction in total cholesterol (PRE: 164 ± 34 and POST: 148 ± 29, p = 0.001), triglycerides (PRE: 118 ± 59 and POST: 104 ± 53, p = 0.002) and lipoproteins density (PRE: 100 ± 29 and POST: 85 ± 26, p = 0.001), but not for high-density (p = 0.981). Both the LE (PRE: 8.8 ± 1.4 and POST: 7.8 ± 1.3, p = 0.001) and LD (PRE: 13.6 ± 1.3 and POST: 12.9 ± 1, 1, p = 0.001) experienced a decrease in its proportions. Conclusion: The concurrent training was effective in combating some risk factors to the accumulation of fat in the liver, as well as in reducing fat in both lobes of the organ in young obese.

Effects of bovine somatotropin injection on serum concentrations of progesterone in non-lactating dairy cows

The objective of this experiment was to evaluate the effects of bovine somatotropin administration on serum concentrations of glucose, insulin, NEFA, IGF-I, and progesterone (P4) in ovariectomized non-lactating dairy cows receiving exogenous P4, as a model to estimate treatment effects on hepatic P4 degradation. Ten non-lactating, non-pregnant, and ovariectomized Gir×Holstein cows were assigned to the experiment (d -14 to 27). On d 0, cows were ranked by BW and BCS, and randomly assigned to one of two treatments: (1) bovine somatotropin (BST; n=5) or (2) saline control (control; n=5). Cows assigned to the BST treatment were administered s.c. injections containing 500. mg of sometribove zinc on d 0, 9, and 18 of the experiment, whereas control cows concurrently received a 10-mL s.c. injection of 0.9% saline. On d -2, cows were inserted with an intravaginal releasing device containing 1.9. g of P4, which remained in the cows until the end the experiment (d 27). Cow BW and BCS were assessed on d -14, 0, and 27. Blood samples were collected daily from d 0 to d 27, at 0 (immediately before), 1, and 2. h relative to concentrate feeding for determination of serum glucose, insulin, NEFA, P4, and IGF-I concentrations. Concentrations of glucose, NEFA, and insulin obtained prior to feeding (0. h) were used to determine pre-prandial revised quantitative insulin sensitivity check index (RQUICKI). No treatment effects were detected for BW (P=0.72) and BCS change (P=0.79) during the experiment. Beginning on d 2 of the experiment, BST cows had greater (P≤0.01) serum IGF-I concentrations compared with control cohorts (treatment×day interaction; P<0.01). Cows receiving BST had greater (P≤0.05) insulin concentrations compared with control cohorts from d 8 to d 11, d 16 and 17, as well as from d 19 to d 21 of the experiment (treatment×day interaction; P<0.01). Cows receiving BST had greater (P≤0.01) mean glucose and NEFA concentrations, as well as reduced (P<0.01) mean RQUICKI during the experiment compared with control cohorts. No treatment effects, however, were detected (P=0.73) for serum P4 concentrations. In conclusion, results from this experiment indicate that hepatic P4 catabolism is not directly regulated by circulating IGF-I, whereas BST administration decreases insulin sensitivity in non-lactating dairy cows in adequate nutritional status. © 2013 Elsevier B.V.

CYP-450 isoenzymes catalyze the generation of hazardous aromatic amines after reaction with the azo dye Sudan III

This work describes the mutagenic response of Sudan III, an adulterant food dye, using Salmonella typhimurium assay and the generation of hazardous aromatic amines after different oxidation methods of this azo dye. For that, we used metabolic activation by S9, catalytic oxidation by ironporphyrin and electrochemistry oxidation in order to simulate endogenous oxidation conditions. The oxidation reactions promoted discoloration from 65% to 95% of Sudan III at 1×10-4molL-1 and generation of 7.6×10-7molL-1 to 0.31×10-4molL-1 of aniline, o-anisidine, 2-methoxi-5-methylaniline, 4-aminobiphenyl, 4,4'-oxydianiline; 4,4'-diaminodiphenylmethane and 2,6-dimethylaniline. The results were confirmed by LC-MS-MS experiments. We also correlate the mutagenic effects of Sudan III using S. typhimurium with the strain TA1535 in the presence of exogenous metabolic activation (S9) with the metabolization products of this compound. Our findings clearly indicate that aromatic amines are formed due to oxidative reactions that can be promoted by hepatic cells, after the ingestion of Sudan III. Considering that, the use of azo compounds as food dyestuffs should be carefully controlled. © 2013 Elsevier Ltd.

Lipid metabolism of commercial layers fed diets containing aflatoxin, fumonisin, and a binder

Aflatoxins (AF) and fumonisins (FU) are a major problem faced by poultry farmers, leading to huge economic losses. This experiment was conducted to determine the effects of AF (1 mg/kg of feed) and FU (25 mg/kg of feed), singly or in combination, on the lipid metabolism in commercial layers and investigate the efficacy of a commercial binder (2 kg/t of feed) on reducing the toxic effects of these mycotoxins. A total of 168 Hisex Brown layer hens, 37 wk of age, were randomized into a 3 × 2 + 1 factorial arrangement (3 diets with no binder containing AF, FU, and AF+FU; 3 diets with binder containing AF, FU, and AF+FU; and a control diet with no mycotoxins and binders), totaling 7 treatments. The hens contaminated with AF showed the characteristic effects of aflatoxicosis, such as a yellow liver, resulting from the accumulation of liver fat, lower values of plasma very low-density lipoprotein and triglycerides, and higher relative weight of the kidneys and liver. Hepatotoxic and nephrotoxic effects of FU were not observed in this study. On the other hand, the FU caused a reduction in small intestine length and an increase in abdominal fat deposition. The glucan-based binder prevented some of the deleterious effects of these mycotoxins, particularly the effects of AF on hepatic lipid metabolism, kidney relative weight, and FU in the small intestine. © 2013 Poultry Science Association Inc.