Effect of Defatted Dabai Pulp Extract in Urine Metabolomics of Hypercholesterolemic Rats.

A source of functional food can be utilized from a source that might otherwise be considered waste. This study investigates the hypocholesterolemic effect of defatted dabai pulp (DDP) from supercritical carbon dioxide extraction and the metabolic alterations associated with the therapeutic effects of DDP using 1H NMR urinary metabolomic analysis. Male-specific pathogen-free Sprague-Dawley rats were fed with a high cholesterol diet for 30 days to induce hypercholesterolemia. Later, the rats were administered with a 2% DDP treatment diet for another 30 days. Supplementation with the 2% DDP treatment diet significantly reduced the level of total cholesterol (TC), triglyceride, low-density lipoprotein (LDL), and inflammatory markers (C-reactive protein (CRP), interleukin 6 (IL6) and tumour necrosis factor-α (α-TNF)) and significantly increased the level of antioxidant profile (total antioxidant status (TAS), superoxide dismutase (SOD), glutathione peroxide (GPX), and catalase (CAT)) compared with the positive control group (PG) group (p < 0.05). The presence of high dietary fibre (28.73 ± 1.82 g/100 g) and phenolic compounds (syringic acid, 4-hydroxybenzoic acid and gallic acid) are potential factors contributing to the beneficial effect. Assessment of 1H NMR urinary metabolomics revealed that supplementation of 2% of DDP can partially recover the dysfunction in the metabolism induced by hypercholesterolemia via choline metabolism. 1H-NMR-based metabolomic analysis of urine from hypercholesterolemic rats in this study uncovered the therapeutic effect of DDP to combat hypercholesterolemia.

Serum and urinary SOD3 in patients with type 2 diabetes: comparison with early chronic kidney disease patients and association with development of diabetic nephropathy.

Extracellular superoxide dismutase 3 (SOD3), one member of the antioxidant defense system and a superoxide scavenger, has been noted to be downregulated in the kidneys of diabetic mice and is characterized by a heparin-binding domain that can anchor the protein to the endothelium and extracellular matrix. The association of the serum and urinary SOD3 levels with diabetic nephropathy in different stages has never been evaluated. It remains unclear how urinary SOD3 changes in different renal diseases. We recruited 98 Taiwanese patients with type 2 diabetes and 10 patients with early chronic kidney disease (CKD) into this study. Biochemical analyses were performed, including evaluation of the serum SOD3, urinary SOD3, urinary albumin, urinary vascular endothelial growth factor (VEGF), and urinary angiotensinogen (ANG). The Kruskal-Wallis rank sum test was used to compare various parameters among the three groups of patients: early CKD, diabetes alone, and diabetes with CKD. Results showed that lower serum and urinary SOD3 levels were observed in the group of patients with diabetes alone. Higher serum and urinary SOD3 levels were observed in the group of patients with diabetes and CKD, which had higher albuminuria and serum creatinine levels. The serum SOD3 levels were significantly positively correlated with renal function, according to the serum creatinine level. The urinary levels of SOD3 were significantly correlated with other urinary biomarkers such as urinary ANG and VEGF. Furthermore, albuminuria can positively predict the serum SOD3 level for the ratio of urinary albumin to urinary creatinine (ACR) >1,190.769 mg/g and the urinary SOD3 level for ACR ≥300 mg/g.

The comparison of oxidative stress effect in classic and tubeless percutaneous nephrolithotomy.

PURPOSE: Surgical stone treatment induces oxidative stress in kidney tissue. We hypothesized that tubeless percutaneous nephrolithotomy (tPCNL) may induce less oxidative stress than classic percutaneous nephrolithotomy (cPCNL) with nephrostomy tube. METHODS: Seventy-two consecutive patients with kidney stones qualified for PCNL were enrolled in the study. Patients were assigned to one of two groups (first group 33 patients-cPCNL and second group 39 patients-tPCNL). Four urine samples were collected in four consecutive days, starting the day before operation. Four oxidative stress markers were analyzed in each sample: catalase (CAT), protein sulfhydryl group (SH), total antioxidant capacity (TAC) and superoxide dismutase (SOD). RESULTS: Baseline mean levels of CAT (IU/l), SH (µmol/l), TAC (mmol/l) and SOD (NU/ml) were 19.4 versus 11.7; 18 versus 58.7; 2.02 versus 1.99; 20.5 versus 22.6 in cPCNL and tPCNL group, respectively. On day two, the levels were 89 versus 104.9; 334.7 versus 518.9; 1.87 versus 1.79; 33.7 versus 41.4, respectively. On the third day, the levels were: 67.4 versus 28.3; 206.8 versus 306.9; 2.01 versus 2.06; 38.2 versus 36.6, respectively. On the fourth day, the concentrations were 47.4 versus 18.5; 129.3 versus 208.7; 2 versus 2.06; 35 versus 45.2, respectively. Significant differences were observed only for CAT and TAC concentrations in days 3 (p = 0.04 and 0.04) and 4 (p = 0.02 and < 0.001) in favor of tPCNL. CONCLUSIONS: CAT, SH and SOD significantly rise after operation. TAC represents the inversion of other parameters. CAT is significantly lower, and TAC is significantly higher in tPCNL postoperatively favoring this method.

The effect of dexmedetomidine on renal function in patients undergoing cardiac valve replacement under cardiopulmonary bypass: A double-blind randomized controlled trial.

STUDY OBJECTIVE: We attempted to explore the effect of Dex on renal function in patients with cardiac valve replacement under cardiopulmonary bypass (CPB). DESIGN: We designed a prospective, randomized, placebo-controlled, single-center, parallel-arm double-blind trial. SETTING: Operating room. PATIENTS: Seven-two eligible patients were randomly divided into Dex group and placebo group. INTERVENTIONS: Dexmedetomidine (Dex) (0.6µg·kg-1) was administered in patients of Dex group at 15min before anesthesia induction, followed by a treatment of 0.2µg·kg-1·h-1 Dex until the end of operation. Patients in placebo group were treated with normal saline equally. MEASUREMENTS: The levels of serum urea nitrogen (BUN), creatinine (Cr), neutrophil gelatinase-associated lipocalin (NGAL), urine interleukin-8 (IL-18) and superoxide dismutase (SOD) activity were tested before anesthesia induction (T1) and after operation at 0, 12h, 24h and 72h (T2-5). The urine output during operation and the post-operative complication of acute kidney injury (AKI) were recorded. MAIN RESULTS: The levels of BUN and Cr were significantly increased at T5, and similar findings were found in the levels of NGAL and urine IL-18 at T3 and T4. The SOD activity was significantly declined at T2 and T3 in the two groups. The levels of BUN and Cr at T5 and the NGAL level at T3 and T4 were significantly lower in Dex group, comparable to placebo group. The intraoperative urine output was significantly increased and the postoperative incidence of AKI was significantly lower in Dex group. CONCLUSIONS: Dex may attenuate the renal injury and decrease the incidence of AKI in patients undergoing cardiac valve replacement under CPB.

Novel Antigen Detection Assay to Monitor Therapeutic Efficacy of Visceral Leishmaniasis.

Visceral leishmaniasis (VL) diagnosis is routinely performed by invasive liver, spleen, bone marrow, or lymph node biopsies, followed by microscopic identification of the parasites. Conventional serological tests cannot distinguish active disease from asymptomatic VL or from cured infection. Here, we report the initial validation of an enzyme-linked immunosorbent assay (ELISA) assembled to detect the Leishmania infantum/donovani antigens iron superoxide dismutase 1 (Li-isd1), tryparedoxin 1 (Li-trx1), and nuclear transport factor 2 (Li-ntf2) as a tool to monitor therapeutic efficacy of VL. The assembled ELISA detected the antigens in the urine samples from seven VL patients before initiation of therapy. Importantly, the antigens were no longer detected in all patients after completion of the treatment. These preliminary observations point to a promising tool to follow treatment efficacy of VL.

Urinary biomarkers of oxidative stress and plasmatic inflammatory profile in phenylketonuric treated patients.

Oxidative stress has been proposed as an important pathophysiologic feature of various inborn errors of metabolism, including phenylketonuria (PKU). Considering that there are few studies relating oxidative stress and inflammation directly in PKU disease, the aim of this study was to evaluate and correlate oxidative damage to biomolecules, antioxidant defenses, pro-inflammatory cytokines, phenylalanine (Phe) and its metabolites (phenyllactic acid--PLA and phenylacetic acid--PAA) levels in urine and plasma from patients with PKU under dietary treatment. We observed a marked increase of isoprostanes, which is a lipid peroxidation biomarker, in urine from these treated patients. Next, we demonstrated that protein oxidative damage, measured by di-tyrosine formation, was significantly increased in urine from PKU treated patients and that decreased urinary antioxidant capacity was also observed. Our findings concerning to the inflammatory cytokines interleukin-6 and interleukin-1ß, both significantly increased in these patients, provide evidence that the pro-inflammatory state occurs. Besides, interleukin-1ß was positively correlated with isoprostanes. We observed a negative correlation between interleukin-6 and interleukin-10, an anti-inflammatory cytokine. Di-tyrosine was positively correlated with Phe, which indicates oxidative damage to proteins, as well as with PAA. These findings may suggest that the protein damage may be induced by Phe and its metabolite PAA in PKU. Our results indicate that pro-oxidant and pro-inflammatory states occur and are, in part, correlated and protein oxidation seems to be induced by Phe and PPA in PKU patients.

Using inflammatory and oxidative biomarkers in urine to predict early acute kidney injury in patients undergoing liver transplantation.

OBJECTIVE: We examined the value of inflammatory and oxidative biomarkers in predicting acute kidney injury (AKI) following orthotopic liver transplantation (OLT). METHODS: Urinary excretion of tumour necrosis factor-α (TNF-α), interleukin-8 (IL-8), interleukin-10 (IL-10), superoxide dismutase (SOD), malondialdehyde (MDA), 6-keto prostaglandin F1α (6-keto-PGF1α), hydrogen peroxide (H2O2), and 8-keto prostaglandin F2α (8-iso-PGF2α), serum creatinine (SCr), blood urea nitrogen (BUN), urinary N-acetyl-beta-D-glucosaminidase (NAG), ß2-microglobulin (ß2-MG) and γ-glutamyl-transferase (γ-GT), were measured before surgery (baseline), at 2 h after graft reperfusion and 24 h after OLT in 28 liver transplantation patients. RESULTS: The levels of TNF-α, IL-8, IL-10, SOD, MDA, 6-keto-PGF1α, H2O2 and 8-iso-PGF2α in urine were all significantly higher in patients who had AKI than in those who did not at 2 h after graft reperfusion and 24 h after OLT (p < 0.01).

[Protection effect and mechanism of Compound Xueshuantong Capsule on diabetic nephropathy rats].

OBJECTIVE: To explore the renoprotective effect of Compound Xueshuantong Capsule (XST) on diabetic rat model with nephropathy. METHODS: Twenty-eight male Sprague Dawley diabetic rats were induced to hyperglycaemia (3 days later, fasting blood glucose > 16.7 mmol/L) by peritoneal injection with streptozotocin (STZ, 50 mg/kg). And they were divided into four groups: diabetic nephropathy (vehicle treatment), irbesartan (20 mg×kg(-1)×d(-1)), low-dosage XST (900 mg×kg(-1)×d(-1)) and high-dosage XST (1800 mg×kg(-1)×d(-1)). Seven normal rats were used as control. After a 12-week intervention, urine protein was examined. Pathological morphology was observed by hematoxylin-eosin (HE), Masson and (periodic acid Schiff) PAS stains. Blood nitric oxide (NO), malondialdehyde (MDA) and blood superoxide dismutase (SOD) and urine SOD were detected. And the expression of (matrix metalloproteinase-2) MMP-2 was detected by Western blot in each group. RESULTS: The model rats presented with hyperglycemia, polydipsia, hyperphagia, polyuria and hyper microalbuminuria. The intervention groups showed decreased microalbuminuria and there was no effect on blood glucose or body weight. Glomerular sclerosis and extracellular matrix (ECM) increased in model group and improved in irbesartan and XST groups as judged by HE, Masson and PAS stains. Three intervention groups had no effect on the elevated expression of MMP-2 in diabetic rats. Compared with the model group, the irbesartan, low-dosage and high-dosage XST groups had significantly decreased blood levels of NO ((104.9 ± 11.0) µmol/L vs (41.9 ± 9.6) µmol/L and (14.7 ± 1.9) µmol/L, P < 0.05) and MDA ((19.6 ± 1.6) nmol/L vs (6.6 ± 0.9) mol/L and (4.5 ± 1.2) nmol/L, P < 0.05), increased blood and urine activities of SOD (blood: (222 ± 20)×10(3) vs (231 ± 18)×10(3) and (237 ± 24)×10(3) U/L,P < 0.05), urine: (11.8 ± 1.1)×10(3) vs (23.3 ± 2.0)×10(3) and (25.7 ± 1.8)×10(3) U/L). CONCLUSION: Compound Xueshuantong Capsule may decrease proteinuria through its suppression of oxidative stress and not its improvement of ECM metabolism.

Identification of novel translational urinary biomarkers for acetaminophen-induced acute liver injury using proteomic profiling in mice.

Drug-induced liver injury (DILI) is the leading cause of acute liver failure. Currently, no adequate predictive biomarkers for DILI are available. This study describes a translational approach using proteomic profiling for the identification of urinary proteins related to acute liver injury induced by acetaminophen (APAP). Mice were given a single intraperitoneal dose of APAP (0-350 mg/kg bw) followed by 24 h urine collection. Doses of ≥275 mg/kg bw APAP resulted in hepatic centrilobular necrosis and significantly elevated plasma alanine aminotransferase (ALT) values (p<0.0001). Proteomic profiling resulted in the identification of 12 differentially excreted proteins in urine of mice with acute liver injury (p<0.001), including superoxide dismutase 1 (SOD1), carbonic anhydrase 3 (CA3) and calmodulin (CaM), as novel biomarkers for APAP-induced liver injury. Urinary levels of SOD1 and CA3 increased with rising plasma ALT levels, but urinary CaM was already present in mice treated with high dose of APAP without elevated plasma ALT levels. Importantly, we showed in human urine after APAP intoxication the presence of SOD1 and CA3, whereas both proteins were absent in control urine samples. Urinary concentrations of CaM were significantly increased and correlated well with plasma APAP concentrations (r = 0.97; p<0.0001) in human APAP intoxicants, who did not present with elevated plasma ALT levels. In conclusion, using this urinary proteomics approach we demonstrate CA3, SOD1 and, most importantly, CaM as potential human biomarkers for APAP-induced liver injury.

Proteomic profiling of dog urine after European adder (Vipera berus berus) envenomation by two-dimensional difference gel electrophoresis.

Between April and September every year, many dogs in Finland are bitten by Vipera berus berus, also known as the European adder, the only venomous snake in the area. Exposure to snake bite venom causes local and systemic symptoms and in severe cases can lead to death. Urine samples were collected from four dogs bitten by V. berus berus and treated in the intensive care unit of the Veterinary Teaching Hospital at the University of Helsinki. The inclusion criteria were a strong suspicion of an adder bite no more than two days before admission and clinical signs of an adder bite. Exclusion criteria were defined as ongoing treatment with glucocorticoids or a known history of liver or kidney diseases. Six privately owned, healthy dogs were obtained as controls. Samples were subjected to 2D-DIGE analysis. Image analysis was performed with DeCyder 7.0 2D software, and protein spots demonstrating a minimum 1.5-fold difference in average spot volume ratios between envenomed and control dogs with a Student's t-test p-value of less than 0.05 were picked and identified using LC-MS/MS. In 2D-DIGE analysis, seven proteins were significantly (p < 0.05) over-expressed in the urine of dogs bitten by V. berus berus compared to the control group. From these, five proteins were identified: beta-2-microglobulin (b2MG), alpha-1-antitrypsin (AAT), albumin, fetuin-B and superoxide dismutase (SOD1). Results indicate that envenomation by V. berus berus alter the urinary protein profile in dogs.

[Effect of dibutyl phthalate and di-(2-ethylhexyl) phthalate on urine SOD activity and MDA content in rats].

OBJECTIVE: To evaluate the effect of dibutyl phthalate (DBP) and di-(2-ethylhexyl) phthalate (DEHP) on urine superoxide dismutase (SOD) activity and malondialdehyde (MDA) content in rats. METHODS: According to 2×2 factorial analysis, 60 adult male SD rats were randomized into 10 groups (n=6), including a control group (fed with sesame oil), 3 DBP groups (fed with DBP at the doses of 30, 100 and 300 mg/kg), 3 DEHP groups (with DEHP at 50, 150, and 450 mg/kg), and 3 DBP+DEHP groups (with 30 mg/kg DBP+50 mg/kg DEHP, 100 mg/kg DBP+150 mg/kg DEHP, and 300 mg/kg DBP +450 mg/kg DEHP). The agents were administered in a single dose through gavage in a volume of 2 ml. After the treatments, the 24, 48, 72, and 96 h urine samples were collected to determine the SOD activity and MDA content. RESULTS: DBP and DEHP, either alone or in combination, significantly decreased SOD activity and increased MDA content in the urine collected at 24 h but not at the other time points. Such changes were gradually reversed with time. CONCLUSION: DBP or DEHP treatment alone can result in significant oxidative damage in the kidney of rats, and the toxic effect of the combined exposure is even more obvious.

Identification and validation of six proteins as marker for endemic nephropathy.

Endemic nephropathy (EN) is defined as a slow progressive renal tubulointestitial disease that mainly occurs in the restricted areas of the Balkan Peninsula. The complexity of the pathogenesis of EN makes its earlier diagnosis very difficult. Urine samples from healthy volunteers from EN regions, EN patients with proteinuria less than 150 mg/L and EN patients with proteinuria more than 150 mg/L, patients with acute kidney injury, patients with diabetic nephropathy and healthy volunteers from Germany were collected. The urinary proteome analyses were performed using 2-D DIGE and mass spectrometry. The validation of biomarkers was investigated by two approaches (Western blot (WB) and dot blot) in successively increasing size - and partially overlapping - sample sets. Comparative and statistical analyses of the proteomics data from the different patient groups allowed the identification of six proteins (alpha-1-microglobulin, alpha-2-glycoprotein-1, beta-2-microglobulin, mannose-binding-lectin-2, protection-of-telomeres-protein-1, and superoxide-dismutase [Cu-Zn]), which were able to discriminate EN with low and high proteinuria from the other groups with high significance (p<0.05). The reliability of the identified proteins as EN marker was underlined with high statistical significance using WB analyses (sensitivity 66.7-98% and specificity 70-100%), whereas the dot blot analyses revealed a decrease in the sensitivity and specificity of these biomarkers.

Early changes to oxidative stress levels following exposure to formaldehyde in ICR mice.

Formaldehyde (FA) is a commonly used chemical in everyday life and can react with many molecules in the human body. Although toxicity has been reported, exposure to FA has also been shown to have beneficial effects or no effect at all. In the present study, we examined the effect of FA inhalation on oxidative stress and inflammation in mice. Male adult ICR mice were exposed FA in gaseous form (0.1 ppm), and blood, urine, brain, lung and liver were obtained for 24 hr. Levels of 8-hydroxy-2'-deoxyguanosine (8OHdG) and NO(3)(-) were then determined by HPLC. A second group of mice were injected with 5 mg/kg lipopolysaccharide (LPS) after 24 hr of FA (3 ppm) inhalation and blood and organs were assayed for NO(3)(-) level and SOD activity. After exposure to a low dose of FA (0.1 ppm), the 8OHdG/dG ratio significantly increased in plasma. However, the ratio in urine and organs significantly decreased during 24 hr of FA exposure. The NO(3)(-) levels mirrored the 8OHdG/dG ratio. After 24 hr exposure to a high dose of FA (3 ppm), NO(3)(-) levels in plasma and liver were significantly lower than in control mice exposed to air only. The SOD activity of blood and urine were conversely increased in FA exposed animals. In the present study, we suggest that inhalation of FA at low doses influences the oxidative stress response in a tissue-specific manner. The FA may partially alleviate in some tissues like preconditioning in oxidative stress.

Effects of 4-phenylbutyric acid on the process and development of diabetic nephropathy induced in rats by streptozotocin: regulation of endoplasmic reticulum stress-oxidative activation.

Oxidative stress may contribute to the pathogenesis of diabetic nephropathy (DN), although the precise regulatory mechanism is still unclear. Recent reports have shown that chemical molecular chaperone 4-phenylbutyric acid (4-PBA) can suppress oxidative stress by attenuating endoplasmic reticulum (ER) stress. We therefore hypothesized that 4-PBA could provide renoprotection through the suppression of oxidative stress in DN rats. Male Sprague-Dawley (SD) rats were randomly divided into three groups: a normal control (NC) group, a streptozotocin (STZ)-induced DN model group, and a DN plus 4-PBA (1g/kg) treatment group. At the end of 4, 8, and 12 weeks, hydroxyproline content, NADPH oxidase activity and the expression of phosphorylation of inositol-requiring enzyme-1alpha (p-IRE1alpha), p47phox, nitrotyrosine (NT) and NF-E2-related factor 2 (Nrf2) in the kidneys of all rats were determined; malondialdehyde (MDA) levels and superoxide dismutase (SOD) activity in serum and urine were also detected; renal nuclear factor kappaB (NF-kappaB) activity in all of the rats was examined at the end of 12 weeks. Compared with the NC group, the DN rats showed a significant increase in hydroxyproline content, NADPH oxidase activity, NF-kappaB activity, the expression of p-IRE1alpha, p47phox, NT and Nrf2 in renal tissue; markedly, MDA levels were higher and SOD activity was lower in serum and urine of DN rats than in NC rats for the indicated time. These alterations were inhibited by the administration of 4-PBA. These findings first demonstrated that treatment with 4-PBA significantly inhibits the process and development of diabetic nephropathy in rats through the regulation of ER stress-oxidative activation.

Urine proteome scans uncover total urinary protease, prostaglandin D synthase, serum amyloid P, and superoxide dismutase as potential markers of lupus nephritis.

To identify potential biomarkers in immune-mediated nephritis, urine from mice subjected to an augmented passive model of anti-glomerular basement membrane (GBM)-induced experimental nephritis was resolved using two-dimensional gels. The urinary proteome in these diseased mice was comprised of at least 71 different proteins. Using orthogonal assays, several of these molecules, including serum amyloid P (SAP), PG D synthase, superoxide dismutase, renin, and total protease were validated to be elevated in the urine and kidneys of mice during anti-GBM disease, as well as in mice with spontaneously arising lupus nephritis. Among these, urinary protease was the only marker that appeared to be exclusively renal in origin, whereas the others were partly serum-derived. Longitudinal studies in murine lupus demonstrated that total urinary protease had better predictive value for histologically active nephritis (r = 0.78) compared with proteinuria (r = -0.04), azotemia (r = 0.28), or the other markers examined, whereas urine SAP emerged as the single most predictive marker of histological glomerulonephritis. Collectively, these studies uncover total urinary protease, PG D synthase, SAP, and superoxide dismutase as novel biomarkers of anti-GBM disease and lupus nephritis, with stronger correlation to renal disease compared with currently employed biomarkers. These findings could have important diagnostic and prognostic ramifications in the management of these renal diatheses.

Dose response and time course studies on superoxide dismutase as a urinary biomarker of carbon tetrachloride-induced hepatic injury in the Hanover Wistar rat.

Previous studies have shown that the enzyme copper/zinc superoxide dismutase (SOD-1) is increased in the urine of rats with carbon tetrachloride (CCl(4))-induced hepatotoxicity. The present experiments aimed to investigate further the usefulness of urinary SOD-1 as a non-invasive biomarker of liver injury. Two investigations were carried out, a dose response study and a time course study. In the dose response study, rats were given a single dose of CCl(4) at 0 (control), 0.10, 0.15, 0.20, 0.25, 0.30, 0.35, 0.40 and 0.80 ml/kg and urine samples collected from 12 to 36 h postdosing. In the time course study, rats were dosed at 0.80 ml/kg CCl(4) and urine sampled at 4, 12, 24 and 36 h postdosing. In both studies, the presence of SOD-1 in the urine was confirmed by Western blotting with an SOD-1 antibody. In the dose response study, serum SOD activity was elevated in all CCl(4)-treated animals and urinary SOD-1 activity was increased 2.2 times at the lowest dose (0.10 ml/kg) and 60.4 times at the highest CCl(4) dose level (0.80 ml/kg). In the time course study, urinary SOD-1 was first detected in samples collected from 4 to 12 h postdosing. We conclude that urinary SOD-1 has potential as a sensitive non-invasive biomarker of CCl(4)-induced hepatocellular injury.

Anti-oxidant enzymes and related elements in term and preterm newborns.

BACKGROUND: Although oxidative stress-related diseases mostly affect neonates with extremely low birthweight, healthy preterm newborns might also be at risk of oxidative damages. The aim of the present study was to verify this possibility. METHODS: Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG), erythrocyte glutathione peroxidase (GSHPx) and superoxide dismutase (SOD), plasma and erythrocyte concentrations of selenium, zinc and copper were measured until 100 days of life in 30 preterm infants with mean +/- SD birthweight and gestational age of 1605 +/- 122 g and 34.5 +/- 0.5 weeks. The control group included 30 term infants with birthweight 3123 158 g and gestational age 39.6 0.7 weeks. RESULTS: Throughout the study period urinary 8-OHdG, taken as a marker of oxidative stress, was significantly higher in the preterm than in the term group. Up until 20 days of life, GSHPx activity was significantly lower in the preterm than in the term infants but this was not associated with any apparent selenium deficiency. Conversely, up until 100 days, preterm infants had significantly reduced SOD levels that appeared to reflect a shortage of the elements needed for this enzyme's activity, notably copper, the plasma concentrations of which were constantly and significantly below the control values. CONCLUSION: The nutritional status of the elements related to the anti-oxidant enzymes, especially zinc and copper, should be carefully assessed in preterm infants, even if their birthweight is not extremely low.

Identification of superoxide dismutase as a potential urinary marker of carbon tetrachloride-induced hepatic toxicity.

The aim of this study was the identification of a novel protein marker of hepatotoxicity in rat urine. Rats were dosed by gavage with carbon tetrachloride (CCl(4)) to induce acute liver injury. Surface enhanced laser desorption/ionisation (SELDI) ProteinChip technology revealed the appearance of a 15.7 kDa protein in the CCl(4)-treated rat urine. One-dimensional sodium dodecyl sulphate polyacrylamide electrophoresis (SDS-PAGE) identified an 18.4 kDa protein in the CCl(4)-treated rat urine. The appearance of either protein was coincident over a time course during which they first appeared at 12h post-dosing, peaked at 36h and had disappeared again within 3 days post-dosing. The protein was identified by in-gel digestion and nano-electrospray (nano-ES)-tandem mass spectrometry as Cu/Zn superoxide dismutase (SOD-1). SOD activity was found to be increased by 61.4-fold in CCl(4)-treated rat urine. Western blots of tissue homogenates from the rats revealed a time-dependent loss of SOD-1 from the livers of CCl(4)-treated rats matching the time course of SOD-1 appearance in urine. SOD-1 is not specifically located in liver; however, its appearance in urine in response to acute CCl(4)-induced hepatotoxicity is a novel finding; this coupled with loss from the liver following injury suggests urinary SOD-1 may be a potential marker of hepatotoxicity.

Comprehensive characterization of serum clinical chemistry parameters and the identification of urinary superoxide dismutase in a carbon tetrachloride-induced model of hepatic fibrosis in the female Hanover Wistar rat.

Carbon tetrachloride (CCl(4)) was used to induce liver fibrosis in the rat. Using this model, we have identified changes in serum and urinary clinical chemistry parameters, and characterized histopathological lesions in the liver. Two experiments were conducted. In Experiment 1, rats were dosed at six levels of CCl(4) (0.06-0.36 ml/kg) twice weekly for 6 weeks, followed by a 6-week non-dosing recovery period (week 12). Livers were removed for histology at 6 and 12 weeks and serum parameters analysed. In Experiment 2, rats were given seven dose levels of CCl(4) (0.4-1.0 ml/kg) twice weekly for 6 weeks, followed by a 6-week recovery period (week 12); urine samples were analysed at 3, 6, 9 and 12 weeks using one-dimensional sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). Liver fibrosis was evident at 6 weeks in Experiments 1 and 2, and the activity of serum enzymes (including alanine aminotransferase, aspartate aminotransferase and glutamate dehydrogenase) was increased. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis (Experiment 2) revealed a protein band at 18.4 kDa in urine from rats treated with CCl(4), not present in control urine, which was identified as copper/zinc superoxide dismutase (Cu/Zn SOD). Western blotting revealed that SOD was increased in urine from rats treated with CCl(4) at 3 and 6 weeks, but not at 9 and 12 weeks. We conclude that Cu/Zn SOD is a urinary marker of hepatic necrosis, but not hepatic fibrosis.

Trace element status in Saudi patients with established atherosclerosis.

BACKGROUND: Traditional coronary risk factors do not fully explain variations in the incidence of cardiovascular disease (CVD). Epidemiological studies have implicated perturbations in selenium, copper, and zinc metabolism in the aetiology of CVD. However, these studies have been principally undertaken in Caucasian populations, in whom trace element intake is generally sufficient. METHOD: We have measured serum and urine selenium, copper, and zinc; and superoxide dismutase, glutathione peroxidase, and lipid peroxide concentrations in 130 Saudi male subjects with established CVD, and 130 age-matched controls. RESULTS: Diabetes mellitus, positive smoking habit (p<0.0001 for both), and hypertension (p<0.05) were more prevalent among CVD patients. Urinary copper (p<0.0001) and zinc (p<0.05) were higher among controls. Serum selenium concentrations were lower among CVD patients (p<0.001), and a high proportion (52%) had selenium levels below 79mug/L compared to controls (22%) (p<0.0001). Conditional logistic regression analysis, showed the characteristics differentiating CVD patients from controls were serum zinc (odds ratio (OR) 0.92, confidence interval (CI) 0.85-0.99, p<0.05), serum copper/zinc ratio (OR 0.31, CI 0.10-0.96), serum selenium (OR 0.07, CI 0.02-0.31, p<0.0001), and urine selenium (OR 3.34, CI 1.40-7.99, p<0.01). CONCLUSION: Measures of trace metals status appear to be associated with the risk of atherosclerosis in a Saudi male population.