Remise Gelisgen

Protein oxidation markers in women with and without gestational diabetes mellitus: a possible relation with paraoxonase activity.

AIMS To clarify the levels of protein oxidation markers such as protein carbonyl (PCO), protein hydroperoxides (P-OOH), advanced oxidation protein products (AOPP) and nitrotyrosine (NT), as well as antioxidative enzymes such as paraoxonase (PON-1) in women with and without gestational diabetes mellitus (GDM). METHODS The study was conducted on 23 women with GDM and 22 women without GDM. The levels of the P-OOH, AOPP, and PON-1 were determined by colorimetric methods; whereas NT and PCO levels were measured by ELISA. RESULTS The concentrations of protein oxidation markers were significantly increased and PON1 activity was significantly decreased in GDM group compared to those of normal pregnant women. The control group showed a significant negative correlation between PON-1 and PCO (r=-0.451, p=0.027); whereas in GDM group, there was a significant positive correlation between P-OOH and HbA1c (r=0.89, p=0.001). There was no significant correlation between AOPP, PON-1, P-OOH, PCO, and HbA1c in either group. CONCLUSIONS There is evidence of a possible association between protein oxidation and decreased PON1 activity in GDM. The increase in protein oxidation parameters in the GDM group leading to decreased PON1 activity might, we think, create a predisposition for clinical complications in GDM group.

Ischemia‐modified albumin and advanced oxidation protein products as potential biomarkers of protein oxidation in Alzheimer's disease

The aim of the present study was to determine the systemic levels of oxidative stress markers, such as ischemia‐modified albumin (IMA), advanced oxidation protein products (AOPP), ferric reducing antioxidant power (FRAP) and the prooxidant–antioxidant balance (PAB), to clarify protein redox homeostasis in patients with Alzheimers disease, and to compare them with mentally healthy persons of the same age.

The efficacy of donepezil administration on acetylcholinesterase activity and altered redox homeostasis in Alzheimer’s disease

Alzheimers disease (AD) is a serious multifactorial disorder with progressive neurodegenerative outcomes related with impaired redox homeostasis. Inhibition of the enzyme acetylcholinesterase (AChE), as one of the major therapeutic strategies, is considered to be offering only symptomatic relief and moderate disease modifying effect. We intended to investigate the effects of acetylcholinesterase inhibition via donepezil on protein carbonyl (PCO), advanced protein oxidation products (AOPP) and ischemia modified albumin (IMA) as protein oxidation markers and ferric reducing antioxidant power (FRAP), prooxidant-antioxidant balance (PAB), total thiol (T-SH), protein thiol (P-SH) as antioxidant status markers and also kynurenine (KYN), N-formyl kynurenine (N-FKYN) and protein bound dityrosine (DT) levels all in one demonstrating the redox homeostasis in Alzheimer patients also correlated with AChE activity. The AChE activity and PCO, KYN, N-FKYN and DT levels were found to be significantly higher in the AD group than the control group. The FRAP, T-SH and P-SH levels were significantly lower in the AD group than in the control group. The AChE activity was significantly higher both in donepezil treated and untreated groups when compared with the control group. PCO levels were significantly higher in Alzheimers untreated group than the healthy control and donepezil treated groups. AChE activity was positively correlated with PCO, IMA, PAB, KYN and N-FKYN levels and negatively correlated with FRAP, T-SH and P-SH levels in all participants. Our data showed that treatment with donepezil had ameliorating effects on redox homeostasis in Alzheimer patients. AChE inhibition seems to be exhibiting a potent antioxidant role and may inhibit protein oxidation by decreasing AChE activity in AD, thus medicinal natural substances exhibiting the similar mechanism of action with their antioxidant behaviours can be recommended for the emphasis on new drug new drug development. Further clinical and experimental studies are needed to support our current findings and conclusions.

The role of feed regulating peptides on weight loss in patients with pulmonary tuberculosis.

PURPOSE Malnutrition is a prominent feature of tuberculosis (TB). The aim of our study was to explore the function of plasma regulatory proteins in pulmonary TB and to investigate the relationship between these parameters and loss of body weight. METHODS Plasma levels of fasting insulin, leptin, ghrelin, adiponectin and orexin-A were measured in 23 pulmonary TB patients, 39 patients with pulmonary sarcoidosis, 22 patients with different diffuse interstitial lung diseases and 21 healthy patients serving as controls. RESULT Plasma leptin (p<0.001) and orexin-A (p<0.01) levels were significantly decreased in TB patients compared with those of the other study subjects. TB patients also had higher levels of plasma ghrelin compared with those of the other study subjects, while sarcoidosis patients had higher plasma adiponectin levels than the other study subjects. Glucose levels were similar in all groups, yet, insulin and Homeostasis Model of Assessment-Insulin Resistance (HOMA-IR) levels were significantly higher in the TB group compared to the other study groups. There was no correlation between leptin, ghrelin, adiponectin and orexin-A and other parameters. CONCLUSIONS These data suggest that leptin and orexin-A levels have effects on weight loss in patients with pulmonary tuberculosis. Particularly, leptin may play a role in the early immune response to pulmonary TB and prolonged inflammation may further suppress leptin production. Measurement of HOMA-IR can indeed be used as a marker for the risk of activated TB. Further clinical studies are needed to better understand the role of feed regulating proteins in pulmonary tuberculosis.

The effects of fluoxetine on circulating oxidative damage parameters in rats exposed to aortic ischemia–reperfusion

Oxidative stress and reperfusion injury may develop in different ischemia-reperfusion (IR) models. Growing evidence links altered lipid protein redox-homeostasis with IR. The effect of fluoxetine (FLX; N-methyl-3-[4-(trifluoromethyl) phenoxy] benzenepropanamine), on the lipid protein redox-homeostasis mechanisms in the rats exposed to aortic IR is unclear. We aimed to investigate the effects of FLX on circulating protein oxidation and lipid peroxidation parameters, such as ischemia modified albumin (IMA), lipid hydroperoxide (LOOH), prooxidant antioxidant balance (PAB), erythrocyte glutathione (GSH), CuZn-superoxide dismutase (CuZn-SOD), ferric reducing antioxidant power (FRAP), as potential IR biomarkers. Wistar rats were randomized into three groups (n=7/group): 1) Control (sham laparotomy); 2) IR without FLX, (60min ischemia and 120min reperfusion); 3) IR with FLX (FLX+IR) (FLX 20mg/kg/day, i.p. for three days before surgery). All of the aforementioned parameters (IMA, LOOH, PAB, GSH, CuZn-SOD, and FRAP) were measured spectrophotometrically. IMA, LOOH, and PAB levels in IR group were significantly higher than the control (P<0.01 respectively) and fluoxetine groups (P<0.01, P<0.01, and P<0.05 respectively), whereas CuZn-SOD activities, GSH and FRAP were significantly lower in IR groups. Fluoxetine group significantly reduced IMA when compared to IR group (P<0.001) and control group (P<0.01). With respect to IMA, LOOH and PAB, impaired redox homeostasis is substantially more prominent in aortic IR. The antidepressant FLX has profitable effects on circulating redox status in rats exposed to aortic IR. FLX administration before IR might decrease the surgery-enhanced free radical production; taken together, the antioxidant effects of FLX supplementation should be considered in future studies.

The relationship between circulating irisin, retinol binding protein-4, adiponectin and inflammatory mediators in patients with metabolic syndrome

OBJECTIVE We wanted to investigate whether there is a relationship between circulating irisin, retinol binding protein-4 (RBP-4), adiponectin and proinflammatory mediators implicated in the development of insulin resistance (IR) in metabolic syndrome (MetS). SUBJECTS AND METHODS In 180 individuals, including controls and patients with MetS, we measured fasting plasma insulin, high sensitivity C-reactive protein (hsCRP), pentraxin-3 (PTX-3), interleukin-33 (IL-33), irisin, RBP-4, and adiponectin using ELISA kits. RESULTS While fasting plasma hsCRP, PTX-3, IL-33, irisin, RBP-4 concentrations were higher, adiponectin levels were lower in patients with MetS than in controls. A correlation analysis revealed that plasma irisin levels were positively associated with MetS components such as waist circumference and waist-hip ratio, low density lipoprotein (LDL) and markers of systemic inflammation such as PTX-3, hsCRP, uric acid, and RBP-4. Adiponectin levels were negatively associated with waist circumference, waist-hip ratio, PTX-3 and LDL. CONCLUSIONS Although the precise mechanisms are still unclear, irisin, RBP-4, adiponectin and PTX-3 are hallmarks of the MetS, which is related to low-grade inflammation. It is conceivable that irisin and adiponectin might contribute to the development of MetS and may also represent novel MetS components. Future clinical studies are needed to confirm and extend these data.

Oxidative stress parameters and inflammatory and immune mediators as markers of the severity of sepsis

INTRODUCTION Sepsis is a complex inflammatory syndrome with diverse etiology and wide spectrum of severity. The aim of this study was to investigate whether inflammatory mediators, in comparison with oxidative parameters, are associated with severity of sepsis. METHODOLOGY Plasma neopterin, adenosine deaminase (ADA), vascular cell adhesion molecule (VCAM), intracellular adhesion molecule (ICAM), interleukin (IL)-1, IL-6, and tumor necrosis factor alpha (TNF-α), as inflammatory mediators, and serum nitric oxide (NOx), nitrotyrosine (NT), oxidized LDL (oxLDL) levels, serum paraoxonase 1 (PON1) activity, and erythrocyte glutathione (GSH) levels as oxidative stress parameters of 12 patients with mild sepsis, 25 patients with severe sepsis, and 20 healthy control subjects were evaluated. NOx, GSH levels and PON1 activity were determined by colorimetric methods, whereas neopterin, VCAM, ICAM, IL-1, IL-6, TNF-α, NT, and oxLDL levels were measured by enzyme-linked immunosorbent assay (ELISA). RESULTS All parameters in mild and severe sepsis were significantly different from those of healthy subjects, except ADA activities. Patients with severe sepsis exhibited higher IL-6, TNF-α, NT, and oxLDL levels than patients with mild sepsis. GSH (98%, 98%), oxLDL (98%, 98%), VCAM-1 (99%, 99%), and ICAM-1 (99%, 99%) have much more sensitivitiy and specificity in sepsis. CONCLUSIONS Our results suggest that the oxidative stress and inflammatory response in patients with sepsis were increased and that serum IL-6, TNF-α, NT, and oxLDL levels were correlated with the severity of sepsis. Therefore, increases in these parameters may contribute to the dysfunction or failure of one or more organs, or even death, in sepsis.

The effects of atorvastatin on oxidative stress in L-NAME-treated rats

Abstract Objectives. Current evidence suggests that the beneficial vascular effects of statins are not limited to the statins’ lipid-lowering properties; these drugs can also improve vascular endothelial cell function. Nω-nitro-l-arginine methyl ester (L-NAME) is a potent synthetic nitric oxide inhibitor, and long-term oral L-NAME treatment is used to induce vascular lesions in experimental animal models. Methods. We determined the effects of statins on protein carbonyl (PCO), lipid hydroperoxides (LHP), oxidized low-density lipoproteins (ox-LDL) and antioxidants such as paraoxonase 1 (PON1) and total thiols (T-SH) in long-term L-NAME-treated rats. Adult male Wistar rats were divided into three groups, namely, control, L-NAME-treated (1 mg/mL in drinking water for three weeks), and atorvastatin plus L-NAME-treated (4 mg/kg/day atorvastatin for 1 week during the third week of L-NAME treatment) groups. Results. In the L-NAME group, the ox-LDL, LHP and PCO were higher and the PON1 and T-SH were lower than the concentrations observed for the controls. When compared with the L-NAME group, the L-NAME plus atorvastatin group had significantly lower ox-LDL and LHP and higher PON1 activities. Additionally, the elevated total cholesterol (TC) and low-density lipoprotein-C (LDL-C) in the L-NAME group were decreased by atorvastatin administration. TC and LDL-C were positively correlated with ox-LDL and LHP and negatively correlated with PON1 in all groups. High-density lipoprotein-C (HDL-C) was negatively correlated with ox-LDL. Conclusion. PON1 prevents LDL oxidation and inactivates LDL-derived oxidized phospholipids; its activity showed a pronounced decrease in the L-NAME treatment group and was increased in the atorvastatin group. Based on our findings, we concluded that the atorvastatin had HDL-related antioxidant activity as well as lipid-lowering properties.

YKL-40 in the diagnosis, prediction of prognosis, and platinum sensitivity in serous epithelial ovarian cancer

Objective: To evaluate the use of YKL-40 in the discrimination between benign and malignant adnexal mass and to determine its prognostic value in assessing residual tumor after primary cytoreduction and platinum sensitivity in serous epithelial ovarian carcinoma (EOC). Materials and Methods: During the three years from January 2015 to December 2017, a nonconsecutive series of 100 patient (60 malignant, 40 benign) who underwent surgery for an adnexal mass were enrolled in the study. Preoperatively, serum samples were collected for YKL-40 level analysis. Results: YKL-40 [receiver operator characteristics (ROC)-area under curve (AUC)=0.83] was a significantly better predictor of EOC than cancer antigen-125 (ROC-AUC=0.75). Using a cut-off for YKL-40 of 47.7 ng/mL had a sensitivity of 80% and a specificity of 70%. Higher serum YKL-40 levels were associated with advanced stage, higher grade, residual tumor after primary cytoreduction and recurrence. Platinum-sensitive patients had significantly elevated levels of YKL-40 compared with platinum-resistant or refractory patients. Conclusion: The results obtained from our study support the use of serum YKL-40 for the discrimination between malignant and benign ovarian tumors. YKL-40 levels in patients with serous EOC may also predict disease residual disease after primary cytoreduction and recurrence. Further studies are needed to understand the relationship between YKL-40 and platinum sensitivity.

SELENIUM SUPPLEMENTATION AMELIORATES ELECTROMAGNETIC FIELD-INDUCED OXIDATIVE STRESS IN THE HEK293 CELLS

There is a widespread use of 2.4 GHz electromagnetic radiation emitting devices especially in communication and education. Recent studies show the adverse effects of electromagnetic fields (EMF) such as oxidative stress, cellular damage and apoptosis on tissues. Selenium (Se) has an antioxidant properties by inhibiting oxidative damage being within the structure of antioxidant enzymes like glutathione peroxidase (GSH-Px) and it has also regulatory function for cell cycle and apoptosis. The aim of this study was to investigate the effect of Se on 2.4 GHz frequency EMF exposed human embryonic kidney cells (HEK293) by means of alterations in apoptotic and oxidative stress parameters. Our study was planned as control, EMF, 100 nM Se + EMF, 200 nM Se + EMF groups. EMF groups were exposed to 2.4 GHz EMF for 1 h, element groups were incubated with two different doses of Se added cell culture medium for 48 h before EMF exposure. MDA levels were significantly higher whereas SOD and GSH-Px activities were significantly lower in EMF compared to control. 100 and 200 nM Se + EMF application decreased MDA levels, increased SOD and GSH-Px activities than EMF. Apoptosis and caspase-3 were statistically significantly higher but bcl-2 was lower in EMF than control. Apoptosis and caspase-3 were lower in 100 and 200 nM Se + EMF, although bcl-2 were higher than EMF. In conclusion, Se has protective effects against 2.4 GHz EMF-induced oxidative stress by reducing lipid peroxidation, regulating SOD and GSH-Px activity. Also, Se has inhibitory effect on 2.4 GHz EMF induced apoptosis by increasing the expression of anti-apoptotic protein bcl-2 and suppressing apoptosis regulatory protein caspase-3.