Search

• Investigation of the relationship between greenhouse gas emissions and Tobin's q. • Contrasting market reaction to the changes in GHG emissions by B2B and B2C firms. • The B2B firm's environmental efforts are regarded just as costs by the market. • The B2C firms' efforts to reduce GHG emissions are rewarded by the market. • More stringent regulatory pressure is required in B2B firms to reduce GHG emissions. This paper analyzes the relationship between greenhouse gas (GHG) emissions and the financial performance of business-to-business (B2B) or business-to-consumer (B2C) organizations. We find that Tobin's q is positively associated with higher GHG emissions for B2B firms, implying that GHG emissions reduction is regarded as a necessary cost. Meanwhile, a negative relationship is found for B2C firms, which may be due to consumers responding to climate change issues. These findings contribute to our understanding of the heterogeneous relationship in the existing literature. The evidence also implies on the policy level that more stringent regulatory pressure may be required for B2B firms to reduce their GHG emissions. [ABSTRACT FROM AUTHOR]

Objective: The aim of this study was to assess plasma and/or tissue levels of adhesion and apoptotic molecules, cytokines, nitric oxide metabolites, levels of lipid peroxidation, myeloperoxidase and superoxide dismutase in patients with glioblastoma multiforme and controls. Methods: All the molecules were evaluated in 25 tumors and 30 controls: 15 were normal healthy subjects for plasma and 15 were normal brain tissues that were collected during autopsy. Commercially available kits for measurements were used. Results: Superoxide dismutase was significantly lower in tumors, while all other molecules were significantly elevated compared to the controls (p=0·0001). Superoxide dismutase negatively correlated with plasma interleukin-1beta (p=0·04) and plasma Fas (p=0·016). Plasma intercellular adhesion molecule-1 and vascular cell adhesion molecule-1 correlated positively with plasma 3-nitrotyrosine (p=0·019) and nitrite/nitrate (p=0·019), respectively. Furthermore, plasma interleukin-1beta also positively correlated with plasma nitrite/nitrate (p=0·003). Discussion: These results suggest that there is a complex relationship between pro- and anti-apoptotic molecules in glioblastoma multiforme pathogenesis. Thus, targeting multiple pathways with advanced chemotherapeutic agents or radiotheraupetic regimens following total resections might be helpful in patients with glioblastoma multiforme since preventing a single pathway does not seem to be reasonable. [ABSTRACT FROM AUTHOR]

Abstract: Hypoxia-inducible factor-1 α (HIF-1α) is the major transcriptional factor involved in the adaptive response to hypoxia. The aim of this study was to assess HIF-1α in 22 patients with transitional meningioma (TM) and 26 patients with glioblastoma multiforme (GBM). HIF-1α was assessed using a commercially available enzyme-linked immunosorbent assay-based HIF-1 transcription factor assay. Levels of HIF-1α in TM and GBM were measured using optical density at 450nm, and median values were found to be 0.35 for TM and 0.37 OD for GBM, respectively. There was no statistically significant difference between the two types of tumor (p =0.264). These findings indicate that HIF-1α is elevated in both TM and GBM, suggesting that although hypoxia is one of the most important and powerful stimuli for HIF-1α elevation and consequently angiogenesis, other mechanisms may play roles in HIF-1α stimulation in benign brain tumors such as TM. [Copyright &y& Elsevier]

Objectives: Experimental studies provide evidence that oxidative damage plays a role in the development of vasospasm after aneurysmal subarachnoid hemorrhage (SAH) but data from human studies is still limited. The purpose of this study was to investigate the time course of cerebrospinal fluid (CSF) superoxide dismutase (SOD) and serum malondialdehyde (MDA) changes in patients with aneurysmal SAH. Methods: SOD in CSF and MDA in the serum were detected on days 1–3, 5 and 7 after aneurysmal SAH in 21 patients, and the results were compared with 15 patients with hydrocephalus. The results were also compared with those of clinical parameters including the patient's outcome at 6 months. Results: The mean CSF SOD levels were lower and serum MDA levels were higher than the controls. Patients with a high amount of blood within the cisterns had a trend to decreased SOD while increasing MDA levels. Conclusion: These preliminary results suggest that the levels of antioxidants are decreased after the onset of SAH in the early period, possibly because of increased oxidative stress. Reactive oxygen-mediated oxidative damage may play an important role in inflammation after SAH. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate toothbrushing management and ability of children in relation to age and gender. The study population consisted of 75 children and were divided into three equal groups as 3-5, 6-8 and 9-11 years of age.The grip type during toothbrushing was recorded on videotape. The most preferred grip types were distal (73%) followed by power (43%) and oblique grips (29%). There were a statistically significant differences between age groups and the grip types (p<0.001) but no significant difference was seen between boys and girls in grip preferences (p>0.05).The mean duration of toothbrushing was shorter in 3-5 years of age group (28 seconds) than the 6-8 and 9-11 age groups (35 and 47 seconds respectively). [ABSTRACT FROM AUTHOR]

• We investigate the causality patterns in volatility spillovers between WTI and Brent crude oil prices. • We allow for structural breaks in the series and employ rolling Granger-causality-in-variance tests. • We find that the nature and the direction of Granger-causality patterns between WTI and Brent prices changed over time. • WTI daily price volatility are found to Granger-cause Brent daily price volatility between 2015 and 2019. • Under the uncertainty surrounding the COVID-19 environment, a causal feedback relationship in volatility reappears in 2020. There has been an increase in price volatility in oil prices during and since the global financial crisis (GFC). This study investigates the Granger causality patterns in volatility spillovers between West Texas International (WTI) and Brent crude oil spot prices using daily data. We use Hafner and Herwartz's (2006) test and employ a rolling sample approach to investigate the changes in the dynamics of volatility spillovers between WTI and Brent oil prices over time. Volatility spillovers from Brent to WTI prices are found to be more pronounced at the beginning of the analysis period, around the GFC, and more recently in 2020. Between 2015 and 2019, the direction of volatility spillovers runs unidirectionally from WTI to Brent oil prices. In 2020, however, a Granger-causal feedback relation between the volatility of WTI and Brent crude oil prices is again detected. This is due to the uncertainty surrounding how the COVID-19 pandemic will evolve and how long the economies and financial markets will be affected. In this uncertain environment, commodities markets participants could be reacting to prices and volatility signals on both WTI and Brent, leading to the detection of a feedback relation. [ABSTRACT FROM AUTHOR]

Background: Antioxidants have been considered a rational curative strategy to prevent and cure liver diseases involving oxidative stress. An acute obstructive jaundice rat model was established to investigate the in vivo hepatoprotective efficacy of Rosa pimpinellifolia L., Methods: The experimental jaundice model was performed by binding the main bile duct in 25 male Sprague-Dawley rats. All rats were randomly divided into five groups: first group: laparotomy-sham-only, second group: biliary tract binding (control), and third, fourth, and fifth groups: treatment groups with 250, 500, and 750 mg/kg fruit extracts daily, respectively., Results: Considering dosage, although there was no significant therapeutic effect in the 250 mg/kg of Rosa pimpinellifolia L. group, the best results were found in the 500 mg/kg dose group, while results in the 750 mg/kg dose group showed consistent correlation with proinflammatory response. With regard to biochemical parameters, lipid hydroperoxide level in the rat serum and liver tissue was significantly decreased in all treatment groups. Amadori products, which are one of the early markers of glycol-oxidative stress, showed statistical significance in the treatment., Conclusion: It was revealed that the antioxidant effect of Rosa pimpinellifolia L. was more prominent in the early stages of hepatic injury secondary to oxidative stress.

In this study, we aimed to reveal the pro-inflammatory effects of serum 25-hydroxyvitamin D3 (Vit D) deficiency and insufficiency in new-onset type 2 diabetes mellitus (T2DM) and prediabetes. We recruited 84 prediabetes patients, 94 new-onset T2DM patients and 113 healthy participants. We measured the levels of C-reactive protein (CRP), fibrinogen, ferritin, interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8), tumor necrosis factor-α (TNF-α), nuclear factor kappa-B (NF-κB) and mitogen-activated protein kinase (MAPK) in the serum of the participants. ANOVA Bonferroni and Kruskal-Wallis Dunn tests were used to compare the inflammation markers and vitamin D levels between the groups. Based on covariance analysis with age, gender and BMI, the Vit D levels of the T2DM group were significantly lower ( p < 0.003). Pro-inflammatory markers and CRP were significantly higher in prediabetic and diabetic subjects. In the prediabetes group, IL-1β, IL-6, IL-8, TNF-α and MAPK were significantly higher in those with Vit D insufficiency and deficiency groups. In the T2DM group, IL-1β, IL-6, IL-8, TNF-α, NF-κB, MAPK and CRP were significantly higher in those with Vit D insufficiency and deficiency. Our study emphasizes the pro-inflammatory effects of Vit D deficiency and insufficiency in new-onset type 2 diabetes mellitus and prediabetes.

Introduction: We aimed to evaluate clinical and laboratory findings of hospitalized asthma and chronic obstructive pulmonary disease (COPD) patients with COVID-19 and demonstrate that they have different symptoms and/or laboratory results and outcomes than COVID-19 patients with comorbidity (CoV-com) and without comorbidity (CoV-alone)., Methodology: The data of the demographic, clinical, laboratory findings of hospitalized CoV-alone, asthma, COPD patients with COVID-19 (CoV-asthma, CoV-COPD, respectively), and CoV-com were analyzed., Results: Out of 1082 patients hospitalized for COVID-19, 585 (54.1%) had CoV-alone, 40 (3.7%) had CoV-asthma, 46 (4.3%) had CoV-COPD and 411 (38%) had CoV-com. Cough, shortness of breath, fever and weakness were the most common four symptoms seen in all COVID-19 patients. Shortness of breath, myalgia, headache symptoms were more common in CoV-asthma than the other groups (p < 0.001, p < 0.01, p < 0.05 respectively). Sputum was more common in CoV-COPD than other groups (p < 0.01). COPD group most frequently had increased values, different from the other groups with CRP>5ng/mL in 91.3%, D-dimer > 0.05mg/dL in 89.1%, troponin > 0.014micg/L in %63.9, INR>1.15 in 52.2%, CK-MB>25U/L in 48.5%, PT>14s in 40.9% of patients (p < 0.05, p < 0.001, p < 0.001, p < 0.001, p < 0.05, p < 0.001, respectively). NT-ProBNP was found to have the highest AUC value and the best differentiating parameter for CoV-asthma from CoV-alone. Typical CT findings were present in 44.4% of CoV-alone, 57.5% of CoV-asthma, 28.3% of CoV-COPD and 38.9% of CoV-com groups. CoV-COPD and CoV-com patients died more frequently than other groups (17.8%, 18.5%)., Conclusions: CoV-asthma and CoV-COPD patients might have different symptoms and laboratory parameters than other COVID-19 patients which can guide the physicians., Competing Interests: No Conflict of Interest is declared, (Copyright (c) 2021 Bilun Gemicioglu, Hafize Uzun, Sermin Borekci, Ridvan Karaali, Sebuh Kurugoglu, Pınar Atukeren, Sabri Sirolu, Sinem Durmus, Ahmet Dirican, Mert Ahmet Kuskucu, Fehmi Tabak.)

Objectives: This study was designed to clarify the effects of ghrelin on myocardial and aortic tissues in insulin-resistant rats., Methods: Sprague-Dawley rats were divided into the following groups: control (Group 1), insulin resistance (IR, Group 2), ghrelin (Group 3) and IR+Ghrelin (Group 4) groups. Levels of HOMA-IR, fibronectin, hydroxyproline, collagen-1, collagen-3, matrix metalloproteinase-3, and matrix metalloproteinase-9, and tissue inhibitor of metalloproteinase-1, and oxidative stress parameters as protein carbonyl (PCO), lipid hydroperoxides (LHPs), malondialdehyde, total thiol were determined in myocardial tissue. Expressions of IL-6, NF-κB and TNF-α mRNAs were detected by RT-qPCR. Aorta tissue was stained Masson trichrome., Key Findings: The HOMA-IR level decreased in the IR+Ghrelin group compared with the IR group (P < 0.001). The PCO and LHP concentrations were higher in the IR group compared with control rats (P < 0.05). The PCO level was reduced by ghrelin in the IR+Ghrelin group compared with the IR group (P < 0.001). Ghrelin treatment reduced the mRNA expression levels of IL-6, NF-κB and TNF-α in the IR+Ghrelin group compared with the IR group (P < 0.001). There was no difference among the groups in the histology of aortic tissue., Conclusions: Ghrelin, a regulator of appetite and energy homeostasis, may be effective in regulating oxidative stress and the inflammatory response when impaired by IR. Therefore, ghrelin may reduce the risks of myocardial dysfunction in IR., (© The Author(s) 2021. Published by Oxford University Press on behalf of the Royal Pharmaceutical Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Elderly population and age-related diseases are on the rise. On the contrary, aging studies are technically hard to conduct, because they require elderly animals, the maintenance of which requires ample effort and is expensive. To tackle this problem, D-galactose is used to hasten the aging process in various tissues in rodent models and it has been shown to successfully mimic the oxidative alterations that take place in the natural aging process in various tissues both by our group and others. In the present study, the validity of D-galactose aging model in skeletal muscles was tested both on predominantly slow-twitch (soleus) and rather fast-twitch (gastrocnemius) muscle in male Sprague-Dawley rats and the results are compared with young littermate controls and naturally aged rats. Redox-related modifications in soleus and gastrocnemius were assessed by measurement of protein carbonyl groups, advanced oxidation protein products, lipid hydroperoxides, total thiol, and Cu, Zn-superoxide dismutase activities. In the present study, we provide biochemical evidence demonstrating that D-galactose-induced mimetic aging does result in oxidative stress-related redox alterations that are comparable with the alterations that occur in natural aging in soleus. On the contrary, in the D-galactose-induced mimetic aging of gastrocnemius, even though the oxidative stress markers were significantly increased, the endpoint redox homeostasis markers were not statistically comparable with the redox status of naturally aged group.

To investigate whether the circulating miR-1 (microRNA-1) and miR-21 expression might be used in the diagnosis of heart failure (HF) and silent coronary artery disease (SCAD) in asymptomatic type 2 diabetes mellitus (T2DM) patients and to explore the relationship of these miRs with N-terminal pro-brain natriuretic peptide (NT-proBNP) and galectin-3. One hundred thirty-five consecutive patients with T2DM and 45 matched control subjects were enrolled in the study. This study consisted of the following four groups: control group (mean age: 60.23 ± 6.27 years, female/male (F/M): 23/22); diabetic group (DM) (mean age: 61.50 ± 5.08, F/M: 23/22); DM + SCAD group (mean age: 61.61 ± 6.02, F/M: 20/25); and DM + acute HF group (mean age: 62.07 ± 5.26 years, F/M: 20/25). miR-1 was downregulated in the DM, CAD + DM and HF + DM groups by 0.54, 0.54, and 0.12 fold as compared with controls, respectively. The miR-1 levels were significantly lower in HF + DM than DM with 0.22 fold changes ( p < 0.001); and in patients with CAD + DM group with 0.22 fold changes ( p < 0.001). Similarly, miR-21 was overexpressed in patients with DM, CAD + DM, and HF + DM with 1.30, 1.79 and 2.21 fold changes as compared with controls, respectively. An interesting finding is that the miR-21 expression was significantly higher in the HF + DM group as compared with the CAD + DM group; miR-1 was negatively correlated with NT-proBNP ( r = -0.891, p < 0.001) and galectin-3 ( r = -0.886, p < 0.001) in the HF + DM group; and miR-21 showed a strongly positive correlation with ( r = 0.734, p < 0.001) and galectin-3 ( r = 0.764. p < 0.001) in the HF + DM group. These results suggest that the circulating decreased miR-1 and increased miR-21 expression are associated with NT-proBNP and galectin-3 levels in acute HF + DM. Especially the miR-21 expression might be useful in predicting the onset of acute HF in asymptomatic T2DM patients. The miR-21 expression is more valuable than the miR-1 expression in predicting cardiovascular events of acute HF and the combined analysis of miR-21 expression, galectin-3, and NT-proBNP can increase the predictive value of miR-21 expression.

Background: Hyperbaric oxygen (HBO) therapy may improve cholestasis, increase hepatic regeneration, and decrease oxidative stress in liver. In this study, we aimed to investigate the effects of HBO therapy on hepatic oxidative stress parameters, such as total thiol groups (T-SH), protein carbonyl (PCO), and total antioxidant capacity (TAC) as well as the predictive value of the noninvasive biochemical marker, sialic acid (SA), and prolidase activity in bile duct ligation (BDL)-induced oxidative damage and fibrosis in rats., Methods: We divided 32 adult male Sprague Dawley rats into four groups: sham, sham + HBO, BDL, and BDL + HBO; each group contained eight animals. We placed the sham + HBO and BDL + HBO groups in an experimental hyperbaric chamber, in which we administered pure oxygen at 2.5 atmospheres for 90 min on 14 consecutive days., Results: The application of BDL significantly increased PCO levels and prolidase activity, and decreased T-SH and TAC levels. HBO significantly decreased PCO levels and prolidase activity and increased T-SH and TAC levels in the liver tissues. There was no significant difference in sialic acid levels between any groups., Conclusions: These results indicate that HBO therapy has hepatoprotective effects on BDL-induced injury by decreasing PCO and prolidase activity and increasing antioxidant activities. We therefore suggest that HBO therapy may be useful after BDL-induced injury.

Objectives: Cell adhesion molecules play a major role in various pathological states. The aim of this study was to evaluate the tissue levels of selectins (E-, L-, and P-Selectins), activated leukocyte cell adhesion molecule (ALCAM) and platelet endothelial cell adhesion molecule-1 (PECAM-1) in intracranial meningiomas and compare with the levels in control tissues., Patients and Methods: 20 consecutive patients who were operated on meningiomas (grade-I: 17 and grade-II: 3) and 15 cerebral tissues obtained during the autopsy procedures as a resource for the healthy controls were included in this study., Results: All three selectins', ALCAM and PECAM-1 levels were found to be significantly higher in meningiomas when compared with the control tissues (p<0.001, p<0.001, p<0.001, p<0.05, p<0.001), respectively., Conclusions: According to our results, the adhesion molecules were found to be higher in meningiomas suggesting that they may be involved in the pathological process of this type of brain tumors. We conceive that developing alternate therapies such as immunotherapeutic approaches against brain tumors might be amendatory in the treatment. Since this is the first study performed in meningioma type brain tumors demonstrating and comparing the levels of various adhesion molecules with control tissues, further clinical and experimental studies are needed to support our current findings with higher number of patients., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Objective: To assess oxidant and antioxidant status in patients with common brain tumors; namely meningiomas, low-grade gliomas (LGG) and high-grade gliomas (HGG) and to compare with normal brain tissues., Patients and Methods: Almost nine biomarkers were measured in 59 brain tumors obtained during surgery and 15 normal brain tissues that were collected during autopsy. Results were compared between two groups., Results: In general, protein oxidation and lipid peroxidation increased while antioxidant capacity decreased significantly in tumors compared to the controls (p<0.05) and higher the grade of the tumor, higher the levels of oxidation and lower the anti-oxidation., Conclusions: Reactive oxygen species may play a crucial role in the pathogenesis of these common brain tumors. As the processes at the molecular level understood, targeted-treatment adjunct to surgical removal will be possible to cope with these devastating brain tumors., (Copyright © 2017. Published by Elsevier B.V.)

Alzheimer's 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 Alzheimer's 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., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

Background: Familial Mediterranean Fever (FMF) is an autosomal recessive form of recurrent episodes of fever and an autoinflammatory disease characterized by inflammation of the serous membranes. The clinical diagnosis is supported by the laboratory findings. This study investigated the relationship of Serum Amyloid A (SAA), YKL-40, and Pentraxin-3 (PTX-3) with the FMF disease., Methods: About 50 patients with FMF were enrolled in this study. Patients were divided into three groups according to disease severity score (mild, moderate, and severe). Thirty-seven healthy individuals were included as the control group. Serum SAA, YKL-40, and PTX-3 concentrations were measured using an ELISA kit., Results: Serum SAA and YKL-40 levels of FMF patients were significantly higher than in the control (P < 0.001). PTX-3 levels were found to be higher in patients even though there was no significant difference (P = 0.113). Whereas the positive predictive value was 71.9% for cut-off point of SAA, the positive predictive value was 83.3% for cut-off point of YKL-40. Whereas a significant correlation was detected in SAA and PTX-3 with YKL-40 (respectively; P = 0.036, P < 0.001), there was no correlation between the PTX-3 with SAA (P = 0.219)., Conclusions: YKL-40 can be used together with SAA to support the diagnosis of FMF and to monitor the severity of the disease. In this study, YKL-40 levels were examined for the first time in FMF patients and further studies are necessary using larger patient samples., (© 2016 Wiley Periodicals, Inc.)

It is well known that in vitro storage lesions lead to membrane dysfunction and decreased number of functional erythrocytes. As erythrocytes get older, in storage media as well as in peripheral circulation, they undergo a variety of biochemical changes. In our study, the erythrocytes with different age groups in citrate phosphate dextrose adenine-formula 1 (CPDA-1) storage solution were used in order to investigate the possible effect of gender factor on oxidative damage. Oxidative damage biomarkers in erythrocyte membranes such as ferric reducing antioxidant power, pro-oxidant-antioxidant balance, protein-bound advance glycation end products, and sialic acid were analyzed. Current study reveals that change in membrane redox status during blood-bank storage condition also depends on both gender depended homeostatic factors and the presence of CPDA-1. During the storage period in CPDA-1, erythrocytes from the male donors are mostly affected by free radical-mediated oxidative stress but erythrocytes obtained from females are severely affected by glyoxidative stress.

Objective. Endocan has been shown to be a marker for several cancers and may show degree of malignancy. The aim of this study is to assess tissue levels of endocan in common brain tumors, namely, meningiomas, low-grade gliomas (LGGs), and high-grade gliomas (HGGs). Patients and Methods. Endocan was assayed by commercially available enzyme linked immunosorbent assay (ELISA) kits in a total of 50 brain tumors (20 meningiomas, 19 LGGs, and 20 HGGs) and 15 controls. The results were compared to control brain tissues. Results. Each tumor group showed significant higher levels of endocan compared to controls (p < 0.05). In addition, endocan levels showed steady increase from the least (meningiomas) to the most (HGGs) malignant tumors and positive correlation was noted between the degree of malignancy and endocan level (p = 0.0001). Conclusion. Endocan, a vital molecule for angiogenesis, is expressed in common brain tumors and results suggest that endocan could be a marker for malignancy.

Statins are suggested to possess healing properties due to their antioxidant and antiinflammatory effects in animal ulcer models. In contrary, a clinical report indicated the formation of gastric ulcer by the use of atorvastatin. In this study, we aimed to investigate the effects of atorvastatin (0.5, 5 and 50mg/kg, p.o.) after single (acute) and multiple (subchronic, 5 days) applications on indomethacin-induced gastric ulcer in rats. In both acute and subchronic models high dose atorvastatin (50mg/kg), unlike to lower doses (0,5 and 5mg/kg), significantly aggravated ulcer lesions induced by indomethacin (30 mg/kg) although, a direct ulcerogenic influence was lacking. Proulcerogenic effect of atorvastatin are likely to be associated with decreased mucosal defense mechanisms (GSH and PGE2), and increased neutrophil infiltration and proinflammatory factors (TNF-a and iNOS) possibly via independently from mevalonate pathway. Thus, atorvastatin therapy should be monitorized in patients for an increased risk of gastric ulcer particularly when used concomitantly with NSAIDs., (Copyright © 2015. Published by Elsevier Inc.)

Background: Testosterone biosynthesis gradually decreases with age. Impaired redox homeostasis-related oxidative damage in cellular macromolecules has a high risk for the development of renal insufficiency. Our aim was to study the effects of testosterone replacement therapy on redox homeostasis., Methods: We investigated various oxidative damage biomarkers in kidney. Experimental animals were separated into three groups-naturally aged rats, testosterone-administered naturally aged rats (single dose of 25 mg/kg testosterone enanthate), and their respective young controls., Results: Our results showed that the testosterone-administered naturally aged group shared significant similarities with the young rats with respect to their redox status. In testosterone-administered naturally aged rats, kynurenine, protein carbonyl, advanced oxidation protein products, lipid peroxidation markers, and xanthine oxidase activities were significantly lower and Cu-Zn superoxide dismutase activities and testosterone levels were higher than naturally aged rats. In testosterone-administered naturally aged rats, catalase activities, ferric reducing anti-oxidant power, and testosterone levels were significantly lower and dityrosine, N-formyl kynurenine, protein carbonyl, and protein hydroperoxides were significantly higher than in young rats. On the other hand, in naturally aged rats, Cu-Zn superoxide dismutase, catalase activities, ferric reducing anti-oxidant power, and testosterone levels were lower and dityrosine, kynurenine, protein carbonyl, protein hydroperoxide, advanced oxidation protein products, lipid peroxidation markers, advanced glycation end products, and xanthine oxidase activities were higher than controls., Conclusions: Our results showed that a single dose of testosterone administration has a positive effect on the redox status of the aged kidney. Future studies are needed to clarify the exact molecular mechanism(s) involved in the action of testosterone in maintaining kidney redox homeostasis.

Background: Increased systemic oxidative stress is considered as an important risk factor for prostate cancer occurrence; however, the relationship between impaired redox homeostasis of prostate tissue and aging remains unclear., Objective: In our study, we hypothesized that age-related deterioration of redox homeostasis in prostate tissue may be considered as a predisposing factor for prostate cancer occurrence., Methods: Sprague-Dawley rats were divided into two groups as young control (5 months) and naturally aged (24 months). We investigated the levels of oxidant and antioxidant parameters in prostate tissue., Results: Advanced oxidation protein products, protein carbonyl, non-protein thiol and lipid hydroperoxides levels of aged rats were significantly higher than in the young control rats (p < 0.01, p < 0.05, p < 0.001, p < 0.05, respectively). Additionally, antioxidant activity of Cu-Zn-superoxide dismutase in elderly group was significantly lower than young controls (p < 0.05)., Conclusions: We suggest that increased non-protein thiol levels found in aged rats may prevent further dissemination of oxidative protein damage. We also propose that the increased levels of oxidative protein damage markers and decreased Cu-Zn superoxide dismutase activity in aged prostate may be considered as a predisposing factor for prostate cancer. Further studies are warranted to clarify all these oxidative changes as initiation factors for prostate cancer in the association of aging with prostate cancer.

Background: The effect of the natural aging process on systemic redox homeostasis is previously documented. However, none of the studies specify the effect of experimental aging on systemic redox homeostasis. The purpose of this study is to clarify the ambiguity raised in preliminary reports as to mimetic aging dependency of the type and magnitude of oxidative damage on constituents of plasma., Methods: In the current study, we investigated the interrelationship among various groups of the systemic oxidative damage markers such as protein oxidation products (protein carbonyl groups, protein hydroperoxides, advanced oxidation protein products, protein thiol groups), lipid peroxidation products (malondialdehyde, lipid hydroperoxides, conjugated dienes), glycoxidation adducts (advanced glycation end products), and antioxidant capacity (ferric reducing/antioxidant power, Cu,Zn-superoxide dismutase, total thiol, non-protein thiol). All these markers were measured in plasma of mimetically aged (MA) rats (5-month-old rats subjected to d-galactose-induced experimental aging), naturally aged (NA) rats (24-month-old), and their corresponding young controls (YC) (5months old)., Results and Conclusions: Our current results show that systemic oxidation markers of the MA group share significant similarities in terms of impaired redox homeostasis with the NA rats and may be considered as a reliable experimental aging model for intravascular aging. Additional methodological studies including d-galactose dosage and application time are warranted to clarify the potential involvement of all these systemic redox variations as mechanistic factors in the development of mimetic aging related intravascular deterioration. Reversing or preventing systemic oxidative damage in experimental and natural aging should therefore be considered the primary target for the development of effective therapeutic strategies to prevent or treat age-related vascular disorders., (Copyright © 2014 Elsevier Inc. All rights reserved.)