ABSTRACT
@#To study the effects of nucleoside antiviral drug zidovudine (AZT) on the flexibility of global metabolism and liver glucolipid metabolic balance in mice, male ICR mice were given zidovudine intragastric administration for 12 weeks, and their water and food intake was recorded daily.Serum glucose (GLU) and triglyceride (TG) levels and serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels were detected after 12 weeks of administration.Oral glucose tolerance test (OGTT) and insulin tolerance test (ITT) were performed.HE staining was used to observe the pathological changes of liver.The gene levels of glucose transporter (Glut2), carnitine palmitate transferase (Cpt1α), medium chain acyl-coa dehydrogenase (Mcad), phosphoenolpyruvate carboxykinase (Pepck) and glucose-6-phosphatase (G6pase) were detected by RT-PCR.Western blot was used to detect the protein levels of insulin signaling Akt, P-Akt, Glut2, Mcad and Cpt1α in liver.The results showed that zidovudine significantly decreased lipid metabolism, impaired glucose tolerance, increased liver cell volume, significantly increased liver triglyceride (TG) and non-esterified fatty acid (NEFA) content, increased Glut2 gene expression, down-regulated fatty acid oxidative metabolism genes Cpt1α, Mcad and gluconeogenesis related genes after fasting, and down-regulated protein expression of Cpt1α.The results suggest that zidovudine can induce the disorder of glucose and lipid metabolism after fasting in a dose-dependent manner.
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@#The study developed a metabolic balance model to evaluated the cardiotoxicity of doxorubicin. The rats were divided into 3 groups, control group(saline), low dose group(8 mg/kg of cumulative doxorubicin)and high dose group(15 mg/kg of cumulative doxorubicin). Doxorubicin or saline was intraperitoneally injected and blood sample was collected at day 1, 4, 7 and 10. The concentrations of nitric oxide(NO), B-type natriuretic peptide(BNP)and the activity of glutathion peroxidase(GSH-Px), xanthine oxidase(XOD)in rat plasma were determined. A metabolic balance model based on the four biomarkers was developed to evaluate the doxorubicin cardiotoxicity in rat. Doxorubicin leaded to significant changes of multiple biomarkers, resulting in metabolic balance disruption according to the metabolic balance maps and dynamic parameters of metabolic balance disruption. Moreover, the correlation study showed a good relationship between metabolic balance disruption and ejection fraction(EF). The metabolic balance model provide a novel method to integrally evaluate the doxorubicin-induced cardiotoxicity.
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Objective: To compare the methods of metabolic balance (MB) and fecal monitoring (FM) for evaluating the dietary zinc (Zn) absorption in Tibetan men. Methods: In 14 d field trial on 16 adult Tibetan men, capsules of carmine were given to mark the feces from D4 to D12, and samples of diet, water, feces and urine were collected during the period. In addition, 4.0 mg zinc tracer (enriched with 67Zn) and 1.0 mg recovery indicator ytterbium (Yb) were orally administrated to the subjects in the evening meal of the D5. The ratio of 67Zn/68Zn in fecal samples was determined by inductively coupled plasma mass spectrometry, and then the zinc absorption was calculated based on the principle of isotope dilution. Results: The dietary zinc absorption in Tibetan men was (23.8?3.9) % evaluated by MB and (21.4?4.3) % by FM with significant difference (by paired-samples t test) and linear correlation (Pearson). The unabsorbed zinc tracer and Yb had the similar behavior through the digestive tract, mostly excreted within5 d following the intake. Conclusion: In the 14d metabolic period, the dietary zinc absorption from MB was a little higher than that from FM. Using FM, the metabolic period can be shortened to 4-5 days according to excretion of Yb. Both methods suggested that the dietary zinc absorption in the adult Tibetan men was good.
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Objective: To study the absorption and utilization of dietary iron, zinc and calcium of male adults of Yi nationality, for basic information to prevent and cure diseases related to mineral deficiencies. Method: Twelve young men aged between 20 and 22 from the region lived by Yi nationality were studied in 14 d period with metabolic balance technique. At the beginning of study, their fasting blood hemoglobin and hematocrit, serum ferritin, plasma zinc and calcium concentration were deteimined. During the 4-12 d of the study, experimental diet, subsequent feces and urine samples were also collected for determining the contents of iron, zinc and calcium by flame atom absorption spectrum method, and then apparent absorption rate, apparent utilization rate and metabolic balance of these minerals were calculated. Results: The apparent absorption rate of iron, zinc and calcium was (15.8?6.2)%, (24.5?4.1)% and (32.3?9.7) % and the apparent utilization rate was (1.9?5.7)%, (12.8?4.3)% and (5.5?15.9)% respectively. The metabolic study showed iron balance, and zinc balance, but calcium balance was variable. Conclusion: The intakes of iron and zinc from the diet can meet the requirements, but calcium cannot. More intakes of foods rich in calcium are recommended for Yi nationality.
ABSTRACT
Zinc(Zn) and copper(Cu) balance tests were conducted in patients with diabetes mellitus. The results revealed that the negative balance of Zn and excessive positive balance of Cu were much improved after the management of diabetes mellitus. In addition, a close relationship was found between serum glucose concentration and the disorder of Zn and Cu balance, i.e. serum Zn level, apparent intestinal absorption rate and balance status of Zn were reversely related to serum glucose concentration, whereas urinary Zn, serum Cu level and apparent intestinal absorption of Cu were positively correlated to serum glucose concentration. Poly-factor analysis suggested that hyperzincuria and malabsorption of Zn were the main factors concerning negative Zn balance.