Antioxidant and antigenotoxic effects of lycopene in obstructive jaundice.

BACKGROUND: Obstructive jaundice, a frequently observed condition caused by obstruction of the common bile duct or its flow and seen in many clinical situations, may end up with serious complications like sepsis, immune depression, coagulopathy, wound breakdown, gastrointestinal hemorrhage, and hepatic and renal failures. Intrahepatic accumulation of reactive oxygen species is thought to be an important cause for the possible mechanisms of the pathogenesis of cholestatic tissue injury from jaundice. Carotenoids have been well described that are able to scavenge reactive oxygen species. Lycopene, a carotenoid present in tomatoes, tomato products, and several fruits and vegetables, have been suggested to have antioxidant activity, so may play a role in certain diseases related to the oxidative stress. The aim of the present study was to determine the effects of lycopene on oxidative stress and DNA damage induced by experimental biliary obstruction in Wistar albino rats. MATERIALS AND METHODS: Daily doses of 100 mg/kg lycopene were given to the bile duct-ligation (BDL) rats orally for 14 days. DNA damage was evaluated by an alkaline comet assay. The levels of aspartate transferase, amino alanine transferase, gamma glutamyl transferase, alkaline phosphatase, and direct bilirubin were analyzed in plasma for the determination of liver functions. The levels of malondialdehyde, reduced glutathione, nitric oxide, catalase, superoxide dismutase, and glutathione S transferase were determined in the liver and kidney tissues. Pro-inflammatory cytokine tumor necrosis factor-alpha level was determined in the liver tissues. Histologic examinations of the liver and kidney tissues were also performed. RESULTS: According to this study, lycopene significantly recovered the parameters of liver functions in plasma, reduced malondialdehyde and nitric oxide levels, enhanced reduced glutathione levels, as well as enhancing all antioxidant enzyme activity in all tissues obtained from the BDL group. Moreover, the parameters of DNA damage in the liver and kidney tissue cells, whole blood cells, and lymphocytes were significantly lower in the lycopene-treated BDL group, compared with the BDL group. CONCLUSIONS: Lycopene significantly reduced the DNA damage, and markedly recovered the liver and kidney tissue injuries seen in rats with obstructive jaundice.

The effects of N-acetylcysteine and ozone therapy on oxidative stress and inflammation in acetaminophen-induced nephrotoxicity model.

INTRODUCTION: Acetaminophen (APAP) is an analgesic and antipyretic agent. In overdoses, it is associated with nephrotoxicity. We examined the potential protective effects of N-acetylcysteine (NAC) and NAC + ozone therapy (OT) combination against APAP-induced nephrotoxicity. MATERIALS AND METHODS: Thirty-two male Sprague-Dawley rats were divided into four groups: sham, control (APAP), NAC, and NAC + OT. In the APAP, NAC, and NAC + OT groups, kidney injury was induced by oral administration of 1 g/kg APAP. The NAC group received NAC (100 mg/kg/day). NAC + OT group received NAC (100 mg/kg/day) and ozone/oxygen mixture (0.7 mg/kg/day) intraperitoneally for 5 days immediately after APAP administration. All animals were killed at 5 days after APAP administration. Renal tissues and blood samples were obtained for biochemical and histopathological analyses. Neopterin, tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-10 levels were measured in sera. Malondialdehyde (MDA) levels and glutathione peroxidase (GPx) activities were determined in renal homogenates. RESULTS: NAC and NAC + OT significantly decreased MDA and TNF-α levels and increased IL-10 levels and GPx activities. Serum neopterin and IL-6 levels were not different among all groups. APAP administration caused tubular necrosis in the kidney. The degrees of renal necrosis of the APAP group were higher than the other groups. Renal injury in rats treated with combination of NAC and OT were found to be significantly less than the other groups. CONCLUSIONS: Our results showed that NAC and OT prevented renal injury in rats and reduced inflammation. These findings suggest that combination of NAC and OT might improve renal damages because of both oxidative stress and inflammation.

The relationship between inflammation, endothelial dysfunction and proteinuria in patients with diabetic nephropathy.

OBJECTIVES: Diabetic nephropathy (DN) is a major manifestation of microangiopathy in patients with Diabetes Mellitus (DM). Inflammation is one of the major factors in the formation of endothelial dysfunction. Endothelial dysfunction is a major contributor to the complications of DM. The aim of the present study was to investigate the possible relationship between inflammation, endothelial dysfunction and proteinuria in patients with diabetic nephropathy. MATERIALS AND METHODS: Plasma TNF-α and IL-6, pro-inflammatory cytokines, concentrations were measured in 25 patients with DN and in 30 diabetic control subjects. Also, we evaluated the markers of endothelial dysfunction such as flow mediated dilatation (FMD), nitrate-mediated dilatation (NMD) and carotid intima-media thickness (CIMT). RESULTS: TNF-α, IL-6 and high-sensitivity C-reactive protein concentrations were significantly higher (p = 0.012, p = 0.006 and p < 0.001, respectively) in the patients with DN than the controls. And, urinary protein concentrations were significantly higher (p < 0.001) but eGFR levels were significantly lower (p < 0.001) in the patients with DN. FMD was significantly lower in DN patients (p < 0.001). We have observed that FMD correlated negatively with body mass index (r = -0.424, p < 0.05). And there was also a positive correlation between TNF-α and urinary protein concentrations in the patients with DN (p < 0.05). CONCLUSION: TNF-α, IL-6, hsCRP and urinary protein concentrations are higher in the DN patients. There were no correlations among pro-inflammatory cytokines concentrations and markers of vascular endotelial disfunction. These findings did not show vascular endothelial dysfunction, but may indicate glomerular endothelial dysfunction.

Beneficial effects of N-acetylcysteine and ebselen on renal ischemia/reperfusion injury.

INTRODUCTION: It has been demonstrated that peroxynitrite accompanies acute renal ischemia and contributes to the pathophysiology of renal damage. Therefore, we aimed to investigate the roles of N-acetylcysteine (NAC), a well-known powerful antioxidant, and ebselen (E), a scavenger of peroxynitrite, on renal injury induced by renal ischemia/reperfusion injury (IRI) of rat kidney. MATERIALS AND METHODS: Forty male Sprague-Dawley rats were divided into five groups: sham, renal IRI, renal IRI+NAC, renal IRI+E, and renal IRI+NAC+E. IR injury was induced by 60 min of bilateral renal ischemia followed by 6 h of reperfusion. After reperfusion, kidneys and blood samples were obtained for histopathological and biochemical evaluations. RESULTS: Renal IR resulted in increased malondialdehyde and nitrite/nitrate levels suggesting increased lipid peroxidation and peroxynitrite production and decreased superoxide dismutase and glutathione peroxidase activities. Both NAC and E alone significantly decreased malondialdehyde and nitrite/nitrate levels and increased superoxide dismutase and glutathione peroxidase activities. Additionally in the renal IRI+NAC+E group, all biochemical results were quite close to those of sham group. Histopathologically, the kidney injury in rats treated with combination of NAC and E was found significantly less than the other groups. CONCLUSIONS: Both NAC and E are able to ameliorate IRI of the kidney by decreasing oxidative and nitrosative stresses and increasing free radical scavenger properties. Additionally, combination of NAC and E prevents kidney damage more than when each drug is used alone, suggesting that scavenging peroxynitrite nearby antioxidant activity is important in preventing renal IRI.

Greater Efficiency Observed 12 Months Post-Implementation of an Automatic Tube Sorting and Registration System in a Core Laboratory.

BACKGROUND: Sample classification and registration have been recognized as important and time-consuming processes in laboratories. There is increasing pressure on laboratories to automate processes due to intense workload and reduce manual procedures and errors. The aim of the present study was to evaluate the positive effects of an automatic tube registration and sorting system on specimen processing. METHODS: An automatic tube registration and sorting system (HCTS2000 MK2, m-u-t AG, Wedel, Germany) was evaluated. Turnaround time (TAT), rate of sample rejection and unrealized tests were examined 12 months pre- and post-implementation of the automatic tube sorting and registration system. RESULTS: The mean TAT of routine chemistry immunoassay, complete blood cell count (CBC) and coagulation samples were significantly improved (P<0.001). The number of rejected samples and unrealized tests was insignificantly decreased post-implementation of the system (0.4% to 0.2% and 4.5% to 1.4%, respectively) (P>0.05). CONCLUSIONS: By reducing delays and errors in the preanalytical processing and sorting of samples, significant improvements in specimen processing were observed after implementation of the system. These results suggest that an automatic tube registration and sorting system may also be used to improve specimen processing in a higher-volume core laboratory.

Zinc and homocysteine levels in polycystic ovarian syndrome patients with insulin resistance.

In this study, our objective was to evaluating the value of serum zinc levels as an etiologic and prognostic marker in patients with polycystic ovarian syndrome. We conducted a prospective study, including 53 women with polycystic ovarian syndrome and 33 healthy controls. We compared serum zinc levels, as well as clinical and metabolic features, of the cases. We also compared serum zinc levels between patients with polycystic ovarian syndrome with insulin resistance. Mean zinc levels were found to be significantly lower in patients with polycystic ovarian syndrome than healthy controls. Multiple logistic regression analysis of significant metabolic variables between polycystic ovarian syndrome and control groups (serum zinc level, body mass index, the ratio of triglyceride/high-density lipoprotein cholesterol, and homocysteine) revealed that zinc level was the most significant variable to predict polycystic ovarian syndrome. Mean serum zinc levels tended to be lower in patients with polycystic ovarian syndrome with impaired glucose tolerance than patients with normal glucose tolerance, but the difference was not statistically significant. In conclusion, zinc deficiency may play a role in the pathogenesis of polycystic ovarian syndrome and may be related with its long-term metabolic complications.

Protective effects of curcumin against oxidative stress parameters and DNA damage in the livers and kidneys of rats with biliary obstruction.

Curcumin, a most active antioxidant compound, has been suggested to have potential beneficial effects against most metabolic and psychological disorders, including cholestasis. In the present study, the effects of curcumin against oxidative stress and DNA damage induced by bile duct ligation (BDL) in Wistar albino rats for 14 days were investigated. The rats were divided into three following groups: Sham group, the BDL group and the BDL+curcumin group. A daily dose of 50mg/kg curcumin was given to the BDL+curcumin group intragastrically for 14 days. The biomarkers of hepatocellular damage were decreased in the BDL+curcumin group compared to the BDL group, indicating that curcumin recovered the liver functions. DNA damage as assessed by the alkaline comet assay was also found to be low in the BDL+curcumin group. Curcumin significantly reduced malondialdehyde and nitric oxide levels, and enchanced reduced glutathione levels and catalase, superoxide dismutase, and glutathione S-transferase enzymes activities in the livers and kidneys of BDL group. Curcumin treatment in BDL group was found to decrease tumor necrosis factor-alpha levels in the livers of rats. These results suggest that curcumin might have protective effects on the cholestasis-induced injuries in the liver and kidney tissues of rats.

The relationship between N-acetylcysteine, hyperbaric oxygen, and inflammation in a rat model of acetaminophen-induced nephrotoxicity.

An overdose of acetaminophen (APAP) produces acute tubular necrosis. The aim of this study was to observe the effects of hyperbaric oxygen (HBO) only and combined with N-acetylcysteine (NAC) on inflammatory cytokines in kidney. Thirty-two male Sprague-Dawley rats were divided into four groups: sham, control (APAP), NAC, and NAC + HBO. In the APAP, NAC, and NAC + HBO groups, renal injury was induced by oral administration of 1 g/kg APAP. The NAC group received NAC (100 mg/kg/day). NAC + HBO group received NAC (100 mg/kg/day) intraperitoneally and HBO underwent at 2.8 ATA pressure with 100 % oxygen inhalation for 90 min every 12 h for 5 days. Rats in the sham group received distilled water only by gastric tube. All animals were killed on 6 days after APAP or distilled water administration. Creatinine, urea, neopterin, tumor necrosis factor-α (TNF-α), and interleukin (IL)-6 levels were measured in sera. There was a significant increase in serum creatinine and urea levels in the control group compared to the sham group (in both, p = 0.001). NAC and NAC + HBO significantly decreased serum neopterin, TNF-α, and IL-6 levels compared to control group. APAP administration caused tubular necrosis in the renal. NAC and NAC + HBO treatments significantly reduced APAP-induced renal damage. The results of this study showed that renal dysfunction in APAP toxicity was attenuated by the use of HBO and NAC treatments. The combination of NAC and HBO treatments might be recommended as an effective treatment modality for APAP-induced nephrotoxicity.

Comparison of 1 mg and 2 mg overnight dexamethasone suppression tests for the screening of Cushing's syndrome in obese patients.

OBJECTIVE: Obesity is currently a major public health problem and one of the potential underlying causes of obesity in a minority of patients is Cushing's syndrome (CS). Traditionally, the gold standard screening test for CS is 1 mg dexamethasone overnight suppression test. However, it is known that obese subjects have high false positive results with this test. DESIGN: We have therefore compared the 1 mg and 2 mg overnight dexamethasone suppression tests in obese subjects. Patients whose serum cortisol after ODST was >50 nM underwent and a low-dose dexamethasone suppression test (LDDST); 24-hour urine cortisol was collected for basal urinary free cortisol (UFC). For positive results after overnight 1-mg dexamethasone suppression test we also performed the overnight 2-mg dexamethasone suppression test. PATIENTS: We prospectively evaluated 100 patients (22 men and 78 women, ranging in age from 17 to 73 years with a body mass index (BMI) >30 kg/m2 who had been referred to our hospital-affiliated endocrine clinic because of simple obesity. Suppression of serum cortisol to <50 nM (1.8 microg/dL) after dexamethasone administration was chosen as the cut-off point for normal suppression. MEASUREMENTS: Thyroid function tests, lipid profiles, homocysteine, antithyroglobulin, anti-thyroid peroxidase antibody levels, vitamin B12, folate levels, insulin resistance [by homeostasis model assessment (HOMA)] and 1.0 mg postdexamethasone (postdex) suppression cortisol levels were measured. RESULTS: We found an 8% false-positive rate in 1 mg overnight test and 2% in 2 mg overnight test (p=0.001). There was no correlation between the cortisol levels after ODST and other parameters. CONCLUSIONS: Our results indicate that the 2 mg overnight dexamethasone suppression test (ODST) is more convenient and accurate than 1-mg ODST as a screening test for excluding CS in subjects with simple obesity.