Evaluation of new Beckman Coulter 25(OH) Vitamin D assay and potential improvement of clinical interpretation.

INTRODUCTION: The aim of this study was to assess the analytical performances of the newly developed Access2 25-hydroxyvitamin D (25(OH)D) total immunoassay on two analysers, DxI800 and Access2 (Beckman Coulter, Brea, CA, USA), and compare these two and a recalibrated Modular E 170 25(OH)D assay (Roche Diagnostics, Penzberg, Germany) with reference liquid chromatography tandem-mass spectrometry (LC-MS/MS) with special emphasis on clinical diagnosis. MATERIALS AND METHODS: Beckman immunoassays were assessed for imprecision, accuracy, limit of blank (LoB), limit of detection (LoD), limit of quantitation (LoQ), linearity, interference, and carryover. One hundred and nineteen samples were run on DxI 800, Access2, and E 170, and agreement with the LC-MS/MS method was evaluated. RESULTS: DxI 800 and Access2 assays showed good performances in terms of LoB, LoD, LoQ, linearity, and interference. All immunoassays showed negative biases ranging from - 8.6% (DxI 800) to - 19.2% (Access2). DxI 800 and Access2 systems had proportional biases, and the E170 system had a constant bias with the largest random error. Concordance correlation coefficient values ranged from 0.941 (CI: 0.917-0.958) for DxI800 to 0.854 (CI: 0.811-0.889) for Access2. Kappa (κ) coefficients were found moderate for Dxl (0.709; CI: 0.581-0.837) and E170 (0.771; CI: 0.587-0.844) and fair for Access2 (0.572; CI: 0.428-0.716). CONCLUSIONS: All immunoassays can be used in routine 25(OH)D measurements, still fairly diagnosing patients' status. Recent standardization attempts seem not to contribute too much to clinical diagnosis. A clinical laboratory must at least be aware of its method to avoid misinterpretation of results.

Vitamin E modulates lung oxidative stress, serum copper, zinc, and iron levels in rats with pulmonary contusion.

BACKGROUND/AIM: To evaluate the effects of oxidant/antioxidant mechanisms and levels of trace elements on trauma-stimulated moderate pulmonary contusions after vitamin E administration. MATERIALS AND METHODS: Sixty-three male Sprague Dawley rats were used. Animals were studied in 4 groups. Vitamin E (150 mg/kg) was injected intraperitoneally 30 min after trauma and on the first and second days. Blood samples were obtained for nitric oxide (NO) levels and superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities. Zinc (Zn+2), copper (Cu+2), and iron (Fe+3) were measured in serum. RESULTS: Lung contusion increased serum and tissue NO levels and SOD activities and decreased GSH-Px activities (P < 0.05). Vitamin E significantly (P < 0.05) decreased NO levels and SOD activities and increased GSH-Px. Serum Zn+2, Cu+2, and Fe+3 levels were statistically significantly influenced by the administration of vitamin E (P < 0.05). Group 4 had lower scores compared to Group 3 (P < 0.05) and no difference compared to Group 1 (P > 0.05). CONCLUSION: These results suggest that treatment with vitamin E reduces lung oxidative stress and related mechanisms in isolated lung contusion as demonstrated by an experimental rat model.

Protective effects of erdosteine, vitamin E, and vitamin C on renal injury induced by the ischemia-reperfusion of the hind limbs in rats.

BACKGROUND/AIM: To compare the protective efficacy of erdosteine and vitamins C and E against renal injury caused by hind limb ischemia-reperfusion (I/R). MATERIALS AND METHODS: Rats were split into 4 groups: group I as the control, group II as I/R, group III as I/R + erdosteine, and group IV as I/R + vitamins C and E. Superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GSH-Px) activities and malondialdehyde (MDA) tissue levels were determined. RESULTS: MDA levels were found comparable with the control group in groups II and III. However, they were considerably decreased in group IV when compared to group II (P < 0.01). Additionally, SOD, CAT, and GSH-Px activities were considerably (P < 0.05) decreased in group II. While CAT and GSH-Px activities were restored (P <0.01) by vitamin E and C treatment, SOD activity was not significantly affected. While GSH-Px activities were higher (P < 0.05) with erdosteine administration, SOD and CAT activities were unchanged. CONCLUSION: The protective effect of vitamins C and E is higher than that of erdosteine treatment in reducing the oxidative stress after renal ischemia in this animal model.

Vitamin C as an antioxidant: evaluation of its role on pulmonary contusion experimental model.

BACKGROUND/AIM: To analyze the protective activity of vitamin C on the lungs by assessing biochemical and histopathological analysi after performing an experimental isolated lung contusion model. MATERIALS AND METHODS: Fifty-four male Sprague-Dawley male rats were used. The rats were randomly separated into 4 groups Vitamin C (200 mg/kg) was injected intraperitoneally 30 min after trauma. Blood samples were obtained for myeloperoxidase (MPO) glutirthione peroxidase (GSH-Px), superoxide dismutase (SOD), and catalase (CAT) activities and malondialdehyde (MDA) levels Blood gas analysis and bronchoalveolar lavage was performed. The lung tissue was also extracted for histopathological examination. RESULTS: The lung contusion enhanced MDA, SOD, CAT, and MPO and diminished GSH-Px. Vitamin C administration after th pulmonary contusion was found to diminish the level of MDA and the activities of SOD, CAT, and MPO and to enhance the level of GSH-Px (P < 0.05). Contusion-induced disrupted gas analysis and leukocyte infiltration were both resolved by the vitamin C. CONCLUSION: The present results indicate that vitamin C administration attenuated the oxidative damage and morphological change induced by pulmonary contusion in an experimental rat study.

Comparative analysis of the protective effects of caffeic acid phenethyl ester (CAPE) on pulmonary contusion lung oxidative stress and serum copper and zinc levels in experimental rat model.

The aim of this study was to investigate the effects of caffeic acid phenethyl ester (CAPE) in the lungs by biochemical and histopathological analyses in an experimental isolated lung contusion model. Eighty-one male Sprague-Dawley rats were used. The animals were divided randomly into four groups: group 1 (n = 9) was defined as without contusion and without CAPE injection. Group 2 (n = 9) was defined as CAPE 10 µmol/kg injection without lung contusion. Group 3 (n = 36) was defined as contusion without CAPE-administrated group which consisted of four subgroups that were created according to analysis between days 0, 1, 2, and 3. Group 4 (n = 27) was defined as CAPE 10 µmol/kg administrated after contusion group divided into three subgroups according to analysis on days 1, 2, and 3. CAPE 10 µmol/kg was injected intraperitoneally 30 min after trauma and on days 1 and 2. Blood samples were obtained to measure catalase (CAT) and superoxide dismutase (SOD) activities and level of malondialdehyde (MDA) and for blood gas analysis. Trace elements such as zinc and copper were measured in serum. The lung tissue was also removed for histopathological examination. Isolated lung contusion increased serum and tissue SOD and CAT activities and MDA levels (p < 0.05). Both serum and tissue SOD, MDA, and CAT levels on day 3 were lower in group 4 compared to group 3 (p < 0.05). Further, the levels of SOD, MDA, and CAT in group 4 were similar compared to group 1 (p > 0.05). CAPE also had a significant beneficial effect on blood gases (p < 0.05). Both serum zinc and copper levels were (p < 0.05) influenced by the administration of CAPE. Histopathological examination revealed lower scores in group 4 compared to group 3 (p < 0.05) and no significant differences compared to group 1 (p > 0.05). CAPE appears to be effective in protecting against severe oxidative stress and tissue damage caused by pulmonary contusion in an experimental setting. Therefore, we conclude that administration of CAPE may be used for a variety of conditions associated with pulmonary contusion. Clinical use of CAPE may have the advantage of prevention of pulmonary contusion.

Calorie restriction modulates hippocampal NMDA receptors in diet-induced obese rats.

Calorie restriction (CR) has attracted increased interest since CR enhances lifespan and alters age-related decline in hippocampal-dependent cognitive functions. Obesity is associated with poor neurocognitive outcome including impaired hippocampal synaptic plasticity and cognitive abilities such as learning and memory. N-Methyl-D-aspartate receptors (NMDARs) are linked to hippocampal-dependent learning and memory, which may be stabilized by CR. In the present study, we aimed to establish the effects of CR on NMDARs in CA1 region of hippocampus in obese and non-obese rats. In addition, malondialdehyde (MDA) levels were determined as a marker for lipid peroxidation (LPO) in hippocampus. Four groups were constituted as control group (C, n = 9), obese group (OB, n = 10), obese calorie-restricted group (OCR, n = 9), and non-obese calorie-restricted group (NCR, n = 10). OCR and NCR were fed with a 60% CR diet for 10 weeks. After 10 weeks of CR, the MDA levels significantly decreased in the calorie-restricted groups. Obesity caused significant decreases in NR2A and NR2B subunit expressions in the hippocampus. The hippocampal NR2A and NR2B levels significantly increased in the OCR group compared with the OB group (P < 0.05). In contrast, the hippocampal NR2A and NR2B levels significantly decreased in the NCR group compared with the C group (P < 0.05). Oxidative stress can be prevented by CR, and these data may provide a molecular and cellular mechanism by which CR may regulate NMDAR-mediated response against obesity-induced changes in the hippocampus.

Erdosteine modulates radiocontrast-induced hepatotoxicity in rat.

It has been suggested that reactive oxygen species (ROS) plays an important role in radio contrast media (RCM)-induced ischemia reperfusion tissue injury although antioxidants may have protective effects on the injury. We investigated the effects of erdosteine as an antioxidant agent on RCM-induced liver toxicity in rats by evaluation of lipid peroxidation (as TBARS), catalase (CAT), superoxide dismutase (SOD), reduced glutathione (GSH) and glutathione peroxidase (GSH-Px) values and histological evaluation. Twenty-one rats were equally divided into three groups as follows: control, RCM, and RCM plus erdosteine. RCM was intraperitoneally administered for 1 day. Erdosteine was administered orally for 2 days after RCM administration. Liver samples were taken from the rats and they homogenized in a motor-driven tissue homogenizer. TBARS levels were significantly (p < 0.005) higher in RCM group than in control although SOD activities significantly (p < 0.05) decreased in RCM group. TBARS levels were lower in RCM plus erdosteine group than in control although SOD activity and GSH level increased (p < 0.05) in liver as compared to RCM alone. Erdosteine showed also histopathological protection (p < 0.0001) against RCM induced hepatotoxicity. GSH-Px and CAT activities were not statistically changed by the erdosteine. According to our results, it can be concluded that radiocontrast media can induce oxidative stress in liver as suggested by previous studies. Erdosteine seems to be protective agent on the radiocontrast media-induced liver toxicity by inhibiting the production of ROS via the enzymatic antioxidant system.

The effects of erdosteine on lung injury induced by the ischemia-reperfusion of the hind-limbs in rats.

BACKGROUND: [corrected] The goal of this experimental study was to investigate whether erdosteine has a protective effect against lung injury as a remote organ after hind-limb ischemia-reperfusion (I/R). MATERIALS AND METHODS: The rats were divided into three groups: control, I/R, and I/R + erdosteine. After the experimental procedure, nitric oxide (NO) levels, myeloperoxidase (MPO), adenosine deaminase (ADA), and the activities of xanthine oxidase (XO) were determined on the lung tissue. The levels of NO and activities of MPO were also measured on the bronchial alveolar lavage (BAL). In addition, the lung tissue was examined by histopathology. RESULTS: The lung tissue ADA and XO activities were increased in the I/R group compared with the control group (P < 0.05). In the I/R group, the levels of NO were higher than the control group (P < 0.05), whereas the erdosteine treatment did not alter the NO levels (P < 0.05). The MPO activities increased after I/R in the I/R group compared to both control and I/R + erdosteine group (P < 0.05). The activity of MPO increased in the IR group in comparison with the control group in BAL (P < 0.05). The activity of MPO in the I/R + erdosteine group was significantly lower than the I/R group in BAL (P < 0.05). NO levels increased in all I/R groups compared to control group in BAL (P < 0.05). However, treatment of erdosteine significantly decreased NO levels compared to I/R group (P < 0.05). The animals of the I/R group had total destruction of normal alveolar structure with the intense presence of infiltrating neutrophils and mononuclear phagocytes in histopathological examination. The rat lung exhibited mild degrees of destruction in the erdosteine group. CONCLUSIONS: As a result, erdosteine may be a protective effect for lung injury, decreasing oxidative stress and neutrophil accumulation after hind-limb I/R in rats.

Protective effects of erdosteine and vitamins C and E combination on ischemia-reperfusion-induced lung oxidative stress and plasma copper and zinc levels in a rat hind limb model.

The aim of this study was to investigate the protective effects of erdosteine and vitamins C and E (VCE) on the lungs after performing hind limb ischemia-reperfusion (I/R) by assessing oxidative stress, plasma copper (Cu), and zinc (Zn) analysis. The animals were divided randomly into four groups as nine rats each as follows: control, I/R, I/R plus erdosteine, and I/R plus VCE combination. I/R period for 60 min was performed on the both hind limbs of all the rats in the groups of I/R, erdosteine with I/R, VCE with I/R allowing 120 min of reperfusion. The animals received orally erdosteine one time in a day and 3 days before I/R in the erdosteine group. In the VCE group, the animals VCE combination received one time in a day and 3 days before I/R, although placebo was given to control and I/R group animals. Lung lipid peroxidation (malondialdehyde [MDA]) level, superoxide dismutase (SOD), and catalase activities were increased, although lung glutathione (GSH) and plasma Zn levels decreased in I/R group in lung tissue compared with the control group. Serum MDA level, creatine kinase, and lactate dehydrogenase activities were increased in I/R group compared with the control. Lung MDA and plasma Zn levels and lung SOD activity were decreased by erdosteine administration, whereas lung GSH levels after I/R increased. The plasma Zn levels and lung SOD activity were decreased by VCE administration, although the plasma Cu and lung GSH levels increased after I/R. In conclusion, erdosteine has an antioxidant role on the values in the rat model, and it has more protective affect than in VCE in attenuating I/R-induced lung injury in rats.