Paraoxonase-1 activity in patients with hyperemesis gravidarum

There is increasing evidence that oxidative stress may play a role in the pathophysiology of hyperemesis gravidarum. Serum paraoxonase-1 (PON-1) is a high density lipoprotein (HDL)-associated enzyme that prevents oxidative modification of low density lipoprotein. The aim of the study was to measure the serum levels of PON-1 activity in women with hyperemesis gravidarum. Thirty-four women with hyperemesis gravidarum and 31 healthy pregnant women were enrolled in the study. Serum PON-1 activity was measured spectrophotometrically. Lipid hydroperoxide (LOOH) levels were measured by iodometric assay. PON-1 activity was significantly lower and LOOH levels were significantly higher in pregnant women with hyperemesis gravidarum than in healthy pregnant women (P < 0.0001, for all). There were significant correlations between PON-1 and LOOH, triglyceride, total cholesterol, HDL, low density lipoprotein (LDL) and high sensitive C-reactive protein (HSCRP; P < 0.0001, for all). By using multiple regression analysis LDL, HDL, HSCRP and LOOH were independent determinants of serum PON-1 activity in the study. Decreased PON-1 activity might be related to increased oxidative stress and inflammation in pregnant women with hyperemesis gravidarum. Subjects with hyperemesis gravidarum might be more prone to the development of atherogenesis due to low serum PON-1 activity.     

Effect of vitamin C and zinc on osmotic fragility and lipid peroxidation in zinc-deficient haemodialysis patients

Peroxidation of the membrane lipid structure of red blood cell leads to haemolysis and anaemia in haemodialysis patients. Dietary constituents of antioxidant vitamins and trace elements may play an important role in protecting against oxidant damage. In this study, the effects of supplementation of vitamin C and zinc on osmotic fragility and lipid peroxidation of erythrocytes were investigated in 34 zinc-deficient haemodialysis patients. Sixteen sex- and age-matched normal volunteers acted as controls. Patients were randomized to receive vitamin C (250 mg day(-1)), zinc (20 mg day(-1)) or a placebo treatment for 3 months. The levels of vitamin C, zinc, malondialdehyde (MDA) and osmotic fragility were measured initially and 3 months after supplementation. Mean serum concentration of vitamin C and zinc increased significantly in the groups at the end of the respective study periods. Supplementation with vitamin C and zinc improved osmotic fragility, and decreased the level of MDA in the groups, but some side-effects (i.e. nausea, vomiting, fever, muscle pain, weakness) were observed during the zinc treatment. The results showed that the supplementation of both treatments decreased osmotic fragilty and MDA in zinc-deficient haemodialysis patients. However, vitamin C treatment was found to be safer than zinc supplementation.     

sFas levels increase in response to cisplatin-based chemotherapy in lung cancer patients

The Fas/Fas Ligand (FasL) system and survivin have counteracting roles in cell survival. Therefore, we explored the role of circulating soluble Fas (sFas) and the tissue levels of Fas and survivin with regard to response to chemotherapy in lung cancer patients. Serum samples from 52 lung cancer patients and 54 control subjects (19 benign lung disease and 35 healthy control subjects) were collected prior to and 24 and 48 h after chemotherapy. sFas was statistically significantly higher in the cancer group than that in the control groups (p < 0.001). Baseline (before chemotherapy) sFas values showed a statistically significant inverse correlation with overall survival (r = ?0.599, p < 0.001). There was a significant increase in serum sFas levels 24 h after treatment (p < 0.05). Contrarily, tissue levels of Fas and survivin were not changed following the chemotherapy (p > 0,05). In conclusion, increased sFas may be an indicator of poor outcome in lung cancer patients. However, cisplatin‐based chemotherapy may not be effective via neither the Fas/FasL system nor survivin pathway. Indeed, larger sample size is required for further evaluation. Copyright © 2010 John Wiley & Sons, Ltd.     

Ghrelin is present in teeth

Ghrelin belongs to the family of a gut-brain hormone that promotes food intake and controls energy balance. Recently, it has also been shown to regulate bone formation directly. Dental tissue shares several functional, developmental and anatomical similarities with bone, and in the present study we have investigated the presence of ghrelin in 44 human teeth using immunocytochemistry and radioimmunoassay. Both methods showed that the hormone is present in canines and molars, mainly in the odontoblasts but also in the pulp. Ghrelin could potentially play interesting physiological roles in teeth.     

Metabolic flux analysis in Streptomyces coelicolor under various nutrient limitations

Metabolic flux analysis was applied to Streptomyces coelicolor continuous culture data obtained under nitrogen, phosphate, sulfate, and potassium limitations. The metabolic reaction network involved more than 200 reactions describing the major pathways as well as the secondary metabolism for the production of actinorhodin and excretion of certain metabolites. Linear programming was used for the optimization of specific growth rates and energy requirements. Two types of specific growth rates, stoichiometric and theoretical, were defined, maximized, and compared in order to investigate the microbial potential. Potassium limitation led to the largest and nitrogen limitation to the smallest difference between the stoichiometric and theoretical specific growth rates. Although the value of the maximum theoretical specific growth rate was close to that of the experimental specific growth rate with potassium limitation, this difference was the largest in the case of nitrogen limitation. Energy requirements during different nutrient limitations were also investigated. The model indicated that although the highest actinorhodin production rate was with nitrogen limitation, this was accompanied with the undesired excretion of certain metabolites.     

Obestatin is present in saliva: alterations in obestatin and ghrelin levels of saliva and serum in ischemic heart disease

Ghrelin and obestatin are a single gene products and are a multiple functional peptides that regulates energy homeostasis, and food intake. In the present work, we studied the secretion of ghrelin and its co-secreted peptide obestatin in 44 patients with ischemic heart disease with that of 27 healthy matched controls. Here we first conducted using an immunohistochemistry assay to screen whether human salivary glands have any obestatin immunoreactivity. Then, serum and saliva obestatin and acylated ghrelin levels were determined by using Radioimmunoassay. Our immunohistochemical analysis demonstrated that obestatin was localized in the striated and excretory duct of human salivary gland. We also report for the first time that obestatin, like ghrelin, is present in human salivary gland and saliva. No evidence of the role of obestatin or ghrelin saliva levels in the context of ischemic heart disease was found. Salivary ghrelin and obestatin levels are correlated in controls with the blood levels. Determination of salivary values could represent a non-invasive alternative to serum ones that can be useful in clinical practice.     

The bioactive peptides salusins and apelin-36 are produced in human arterial and venous tissues and the changes of their levels during cardiopulmonary bypass

This study aimed to examine the effects of CPB on salusin-α, salusin-β and apelin-36 bioactive peptides in people who are planned to undergo coronary artery bypass graft (CABG) operation due to coronary artery disease and to explore whether these peptides are produced in human aortic, saphenous and arterial tissues. The study included age and BMI matched 15 patients who underwent CABG operation by CPB. In order to determine salusin-α, salusin-β and apelin-36 levels, venous blood samples were collected before induction of anesthesia (T1), before CPB (T2), 5min before the removal of cross-clamp (T3), 5min after the removal of cross-clamp (T4), upon arrival in the intensive care (T5), at postoperative 24th hour (T6) and 72nd hour (T7). Salusin and apelin expressions of the tissues were shown by immunohistochemical method. Peptide amounts of sera and tissues were measured using ELISA. Salusins production by vessels occurs in fibroblast cells of the media in the aorta and smooth muscle cells of the media in the LIMA and saphena. Apelin is produced by endothelial cells of the intima and fibroblast cells of the media in the aorta and by smooth muscle cells of the media in the LIMA and saphena. Changes in the levels of salusin-β and apelin-36 were significant during CPB. Salusin-α, salusin-β and apelin-36 are locally synthesized in the arteries and veins. Salusins and apelin-36 might be important markers in the CPB, and also that salusin-β was more specific in comparison to salusin-α.