The effects of acute melatonin and ethanol treatment on antioxidant enzyme activities in rat testes

The pineal hormone melatonin (N-acetyl, 5-methoxytryptamine) was recently accepted to act as an antioxidant under both in vivo and in vitro conditions. In this study, we examined the possible preventive effect of melatonin on ethanol-induced lipid peroxidation in rat testes. Thirty-seven male Wistar albino rats, 5.5-6 months old, were randomly divided into four groups (9-10 animals in each). The first group (control animals) received 4% ethanol at similar intervals to the experimental groups to equalize the stress effect. The second group received only melatonin i.p. 7 mg kg(-1) bw three times over 1.5 h intervals. The third group received only 30% alcohol 3 g kg(-1) bw twice daily. The fourth group were treated with melatonin and ethanol according to the above protocole, melatonin injections preceeding ethanol treatments. The product of lipid peroxidation, malondialdehyde (MDA) and antioxidant enzymes, superoxide dismutase (Cu-Zn SOD), glutathione peroxidase (GPx) and catalase (CAT) were measured in the post-mitochondrial fraction of the testes. MDA levels were significantly increased due to acute ethanol intoxication. GPx activity was higher in the three experimental groups than the control levels. The activity of CAT was increased significantly in the melatonin plus ethanol-treated group but the other groups appeared not to be influenced by acute ethanol treatment. Cu-Zn SOD activity remained unaltered. These results suggest that antioxidants may be a protective agent for the testicular injury caused by ethanol consumption. (C) 2001 Academic Press

Determination of diagnostic and prognostic values of urinary interleukin-8, tumor necrosis factor-alpha, and leukocyte arylsulfatase-A activity in patients with bladder cancer

Objectives: This study was planned to evaluate the feasibility of the assay of leukocyte arylsulfatase-A (AS-A) activity, and some urinary cytokine levels (tumor necrosis factor-alpha [TNF-alpha] and interleukin-8 [IL-8]), as noninvasive diagnostic tools in different stages of bladder cancer patients

Evaluation of the effect of low-dose oral theophylline therapy on some bone turnover markers and serum prolidase I activity in mild asthmatics

Hypercalcemia and hypercalciuria observed both in humans and in animals who were on long-term theophylline therapy, prompted us to investigate whether oral theophylline treatment at optimal doses causes any adverse side effects on bone metabolism in mild asthmatics. Therefore, serum osteocalcin (BGP) and total alkaline phosphatase (TALP, EC 3.1.3.1) as bone formation markers, serum prolidase I(EC 3.4.13.9) activity as a marker for collagen metabolism, urinary deoxypyridinoline (Dpd), hydroxyproline (Hyp) and fasting urinary calcium as bone resorption markers, were measured in 18 mild asthmatics who had been treated with theophylline over 1-10 years. Among measured bone turnover markers, BGP, TALP, and Hyp levels were found to be increased in mild asthmatics; and BGP showed the greatest percent mean increase (98%) over the healthy subjects. However, these increments did not exceed the upper reference limits. Serum prolidase I activity was also increased in mild asthmatics receiving theophylline. Our results indicate that theophylline therapy at optimal doses may not exert adverse side effects on bone homeostasis, but patients receiving supratherapeutic doses of theophylline should be under close examination in order to predict future bone mass status. (C) 1999 Academic Press

Circulating ghrelin levels in obese women: a possible association with hypertension

Objective. The orexigenic hormone ghrelin induces weight gain by stimulating food intake. Ghrelin has been shown to modulate sympathetic activity, to exert vasodilative effects and to counterreact with leptin on both food intake and blood pressure. Of these two hormones, ghrelin levels are decreased in obesity, whereas leptin levels are increased. In this cross-sectional study, differences in serum ghrelin and leptin levels were examined in normotensive and hypertensive obese women. Material and methods. Sixty-one normotensive and hypertensive women were classified according to the body mass indices as follows: (a) 18 healthy subjects with BMI 21.5-27.5 kg/m(2); (b) 22 normotensive subjects with BMI 30-47 kg/m2; (c) 21 hypertensive obese subjects (BMI 30-48 kg/m 2) with systolic blood pressure >= 140 mmHg or diastolic blood pressure >= 90 mmHg. Anthropometric measurements including height, weight, BMI, waist and hip circumferences and blood pressure were recorded. The levels of ghrelin and leptin were determined in sera using the commercial ELISA kits. Results. In normotensive obese subjects, ghrelin levels were significantly lower than in controls (0.21 +/- 0.13 vs 0.60 +/- 0.3 ng/mL), whereas hypertensive obese women had elevated ghrelin levels (0.64 +/- 0.36 ng/mL). Ghrelin concentration was decreased despite the presence of hypertension in the patients who had BMIs above 35 kg/m2. Leptin levels were significantly higher in both normotensive and hypertensive obese groups (19.54 +/- 11.19 and 21.61 +/- 12.7 ng/mL, respectively) than in controls (7.61 +/- 3.3 ng/mL), and were not affected by the presence of hypertension in obese subjects. Conclusion. Ghrelin was positively associated with hypertension in obese women and this association was inversely influenced by the increase of BMI

Serum prolidase I activity and some bone metabolic markers in patients with breast cancer: in relation to menopausal status

Objectives: The purpose of this study was to investigate the diagnostic value of some osteoblastic/osteoclastic biochemical markers and serum prolidase I activity in breast cancer (BC)

Advanced oxidation protein products in obese women: its relation to insulin resistance and resistin

Obesity is a major risk factor for insulin resistance and type 2 diabetes mellitus (TZDM). Resistin, an adipocyte-secreted hormone, is thought to take a part in the development of insulin resistance and T2DM. The aim of this study was to characterise the changes in circulating levels of resistin and proinflammatory cytokines tumour necrosis factor-alpha (TNF-alpha) and interleukin (IL)-6 in diabetic and prediabetic obese patients and to explore their relationship to insulin resistance. Attempts were also made to see whether resistin levels are related to the degree of oxidative stress, as determined by the measurement of advanced oxidation protein products (AOPPs). The study groups consisted of obese diabetic (BMI: 30-42 kg/m(2), n=28) and prediabetic (BMI: 29-41 kg/m(2), n=23) women. Fourteen healthy women, with BMI in the range 21.5-25.5 kg/m2, were taken as controls. Serum levels of TNF-alpha, IL-6, resistin, glucose, insulin and AOPPs were measured. Insulin resistance was calculated by the homeostasis model assessment (HOMA-IR). Diabetic and prediabetic obese patients had increases in serum resistin and TNF-a levels (P < 0.01 and P < 0.001, respectively). IL-6 levels in diabetic patients were significantly higher than in prediabetics (P < 0.05). AOPP levels were also significantly higher in diabetics than prediabetics and controls (P < 0.05 and P < 0.001, respectively); and positively correlated with blood glucose. Insulin was significantly associated with circulating resistin and TNF-a. The development of insulin resistance may contribute to the elevation of circulating resistin or vice versa. Determination of AOPPs may be helpful for monitoring the impaired glucose metabolism in obesity

Evaluation of leukocyte arylsulphatase A, serum interleukin-6 and urinary heparan sulphate following tamoxifen therapy in breast cancer

Leukocyte arylsulphatase A (AS-A) was shown to be significantly high in newly-diagnosed breast cancer patients. Previous reports imply a connection between serum interleukin-6 (IL-6) and breast cancer, possibly through a modulation of enzymes involved in estrogen synthesis. Abnormal distribution of heparan sulphate proteoglycans (HSPGs) in malignant breast epithelial cells suggests that they play a key role in the regulation of cell growth. Estradiol is believed to be effective in modulating glycosaminoglycans (GAGs) and their depolymerizing enzymes. Therefore, in this study, attempts were made to evaluate the activity of leukocyte arylsulphatase A, serum interleukin-6, urinary GAGs and heparan sulphate (HS) in response to tamoxifen (TAM) therapy in mastectomised breast cancer patients. Thirty-four patients (aged 30-82 years) were administered TAM (20 mg twice daily). Blood and urine samples of each patient were collected three times (at the beginning, and in third and sixth month of TAM therapy), and biochemical parameters were measured. There was no difference between baseline leukocyte AS-A activity and that measured after three months. At the end of six months, enzyme activity was significantly higher than the former values (p = 0.022), but within the reference intervals reported in the literature. Although this increase might imply a normalization, the duration of TAM therapy is not long enough to make a decision about either regression or aggravation of the disease. TAM did not have any effect on serum IL-6, urinary HS and GAG levels which may be due to insensitivity of these variables to TAM during the short period of therapy. Both urinary GAG and HS levels measured at sixth month exhibited a positive correlation with the baseline level of leukocyte AS-A (P = 0.005 and 0.009, respectively), suggesting that positive responses to the drug might be seen in patients with low AS-A activity. (c) 2005 Elsevier Ltd. All rights reserved