Ulaş Değirmenci

Mersin University, Zephyrium, Mersin, Turkey

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Publications (13)32.93 Total impact

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    ABSTRACT: We examined whether nitric oxide (NO), derived from constitutive NO synthase (NOS) and/or inducible NOS (iNOS), could contribute to endotoxin-induced inflammatory hyperalgesia via interacting with nuclear factor-kappaB (NF-kappaB), inducible cyclooxygenase (COX-2) and/or polyADP-ribose synthase (PARS). Injection of endotoxin (10 mg kg(-1), i.p.) to mice elicited hyperalgesia, determined by hot plate test, which is prevented by NO precursor (L-arginine), cNOS/iNOS inhibitor (N(G)-nitro-L-arginine methyl ester; L-NAME), NF-kappaB inhibitor (N-acetylserotonin), COX inhibitor (indomethacin), COX-2 inhibitor (DFU) and PARS inhibitor (3-aminobenzamide). Endotoxin caused a decrease in serum nitrite levels prevented by N-acetylserotonin, L-arginine, indomethacin, DFU or 3-aminobenzamide. Endotoxin increased serum 6-keto-PGF(1alpha) levels diminished by L-arginine or aminoguanidine (iNOS inhibitor). L-Arginine, L-NAME, aminoguanidine, DFU or 3-aminobenzamide prevented endotoxin-induced decrease in heart, lungs, kidneys and brain nitrite and malonedialdehyde levels and myeloperoxidase activity. In conclusion, NO reverses endotoxin-induced inflammatory hyperalgesia via inhibition of prostacyclin production, and also contributes to the analgesic effect of NF-kappaB, COX or PARS inhibitors.
    Pharmacological Research 03/2006; 53(2):177-92. · 4.35 Impact Factor
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    ABSTRACT: The acetylation polymorphism is a common inherited variation in human drug and carcinogen metabolism. Because N- acetyltransferase (NAT2) is important for the detoxification and/or bioactivation of drugs and carcinogens, polymorphisms of this gene have important implications in therapeutics of and susceptibility to cancer. In this study, NAT2 genotype (NAT2*5A (C(481)T), NAT2*6A (G(590)A), NAT2*7A/B (G(857)A)) and NAT2*14A (G(191)A) and phenotype were determined in 125 patients with colorectal carcinoma and 82 healthy control in Mersin, a city located in the southern region of Turkey. Isolation of the subjects' DNA was performed by using a highly purified PCR template preparation kit/(Roche Diagnostics cat. no: 1 796 828) and the NAT2 polymorphism was detected using real-time PCR (Roche Diagnostics, GmbH, Mannheim, Germany). According to this study high protein intake is associated with the increased risk for the development of colon cancer (OR = 1.73; 95% CI, 1.10-3.07). Although only NAT2*14A fast type was associated with increased risk in patients with colorectal carcinoma (OR = 3.03; 95% CI, 1.56-5.86), when a high protein diet was considered, NAT2*7A/B fast genotype was also found to be associated with an increased risk (OR = 2.06, 95% CI for NAT2*7A/B, 1.10-3.86; OR = 2.65; 95% CI, 1.29-5.46 for NAT2*14A). Smoking status did not differ between the control and patient groups. Our data suggest that exposure to carcinogens through consumption of a high-protein diet may increase the risk of colorectal carcinoma only in genetically-susceptible individuals.
    Cell Biochemistry and Function 02/2006; 24(2):131-5. · 1.85 Impact Factor
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    ABSTRACT: Extracts of propolis, a natural beehive product, have been known for centuries to have a variety of beneficial medical properties, among which their anti-inflammatory effect is a major one. Caffeic acid phenethyl ester (CAPE), an active propolis component, has antimicrobial, anti-inflammatory, antioxidant, carcinostatic and immunomodulatory properties. In this study, we aimed to investigate the efficacy of CAPE in endotoxin-induced lung injury in rats. Lung injury was induced by a footpad injection of lipopolysaccharide (LPS). In the treatment group, 10 micromol kg(-1) CAPE was injected intraperitoneally immediately after LPS injection. At 24 h after LPS and/or CAPE injection, blood and lung tissue specimens were collected. MDA levels and MPO activity in serum and lung tissue, serum total antioxidant levels, lung tissue Na(+)/K(+) ATP-ase activity and histopathological evaluation were determined to assess the efficacy of CAPE treatment. CAPE was found to be efficient in reducing inflammation and lung tissue damage induced by LPS in rats.
    Pulmonary Pharmacology &amp Therapeutics 02/2006; 19(2):90-5. · 2.54 Impact Factor
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    ABSTRACT: The objective of this study was to investigate antioxidant and cytoprotective properties of iloprost in a distant organ after ischaemia reperfusion injury. Male Wistar rats were divided into two groups. After application of anesthaesia both hindlimbs were occluded. A 2-h reperfusion procedure was carried out after 60 min of ischemia. Study group (STU) rats (n=10) received 10 microg kg(-1) iloprost in 1 ml of saline from the tail vein 10 min before reperfusion. Control (CON) group rats (n=10) received an equal amount of saline. The rats were sacrificed by injection of a high dose of thiopentone sodium. Blood and tissue samples (right kidneys) were taken for analysis. Differences in malondialdehyde (MDA), myeloperoxidase (MPO), Na+-K+ ATPase and total antioxidant capacity (TAC) between the groups were analysed. MPO, MDA and TAC levels in the sera of CON and STU groups were 1.60+/-0.26 U l(-1), 11.42+/-5.23 nmol ml(-1), 8.30 x 10(-2)+/- 3.93 x 10(-2) nmol ml(-1) h(-1) and 1.07+/-0.11 U l(-1), 7.60+/-1.81 nmol ml(-1) and 0.15+/-3.23 x 10(-2) nmol ml(-1) h(-1) (p=0.0001, p=0.043 and p=0.0001 respectively). MPO, ATPase and MDA levels in kidneys for CON and STU groups were 1.24+/-0.58 U g(-1), 85.70+/-52.05 nmol mg(-1), 17.90+/-7.40 nmol ml(-1) and 0.78+/-0.31 U g(-1), 195.90+/-56.13 nmol mg(-1) and 10.10+/-0.99 nmol ml(-1) (p=0.046, p=0.0001 and p=0.009 respectively). When given prior to reperfusion, the positive effect of iloprost in the attenuation of distant organ reperfusion injury has been demonstrated.
    Cell Biochemistry and Function 01/2006; 24(4):341-6. · 1.85 Impact Factor
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    ABSTRACT: The purpose of this study was to investigate whether polymorphism of N-acetyltransferase 2 (NAT2) genotypes are associated with the risk of laryngeal squamous cell carcinoma (SCC). The study group consisted of 45 white patients with laryngeal SCC (42 men, with a mean age of 54 years [range, 37-70 years] and three women, with a mean age of 47 years [range, 32-55 years]) and 104 control subjects (68 men and 36 women; mean age, 50 years; range, 28-73 years). All of the patients were primarily treated with surgical intervention. Blood samples (5 mL) were obtained before surgery or from the patients under follow-up to 5 years after surgery (mean follow-up, 27 months; range, 6-48 months). DNA was extracted from the lymphocytes by high pure template preparation kit. NAT2*5A, NAT2*6A, NAT2*7A/B, and NAT2*14A were detected by use of LightCycler-NAT2 mutation detection kit by real-time polymerase chain reaction with Light Cycler instruments. The association between NAT2 polymorphisms and laryngeal SCC was prospectively modeled through multivariate logistic regression analysis. We found that the risk of laryngeal SCC was 7.3-fold higher in individuals with NAT2*5 mutant allele, 3.8-fold higher in subjects with NAT2*6 heterozygote allele, and 38.3-fold higher in NAT2*6 mutant allele. We also found that individuals with NAT2*7 heterozygote allele had a 0.2-fold less risk for the development of laryngeal SCC (p = .018). In this population, patients with NAT2*5 mutant and *6 heterozygous and mutant genotypes had a significantly higher risk for development of laryngeal SCC.
    Head & Neck 01/2006; 27(12):1056-60. · 2.83 Impact Factor
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    ABSTRACT: Caffeic acid phenethyl ester (CAPE) has antimicrobial, anti-inflammatory, antioxidant, immunomodulatory, and carcinostatic properties. In this study, the efficacy of CAPE in endotoxin-induced uveitis (EIU) in rats is investigated. EIU was induced by a footpad injection of lipopolysaccharide (LPS). In the treatment group, 10 micromol/kg CAPE was injected intraperitoneally immediately after LPS injection. At 24 hr after LPS injection, the number of infiltrating cells, protein concentration, and levels of myeloperoxidase (MPO) in aqueous humor; malondialdehyde (MDA), MPO, and total antioxidant levels in serum were determined. Eyes were enucleated for histopathologic evaluation, and, counting inflammatory cells in iris-ciliary body (ICB), the efficacy of treatment was determined. CAPE significantly suppressed LPS-induced increase in the number of inflammatory cells (p = 0.0001), protein concentration (p = 0.0001), and MPO levels (p = 0.0001) in aqueous humor as well as MDA (p = 0.001) and MPO (p = 0.0001) levels in serum. Histopathologic evaluation of ICB showed significant reduction in the inflammatory cell counts in the treatment group (p = 0.0001). CAPE was found efficient in suppressing inflammation and ocular tissue damage induced by LPS in rats.
    Current Eye Research 10/2005; 30(9):755-62. · 1.71 Impact Factor
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    ABSTRACT: Caffeic acid phenethyl ester (CAPE) is a phenolic antioxidant and is an active anti-inflammatory component of honeybee propolis. The authors evaluated the effects of CAPE on oxidative stress and lung damage in an oleic acid (OA)-induced lung-injury model. Rats were divided into 5 groups as sham, OA, CAPE, pre-OA-CAPE, and post-OA-CAPE. Acute lung injury was induced by intravenous administration of 100 mg/kg of OA. Pre-OA-CAPE group received CAPE (10 micromol/kg. intravenously) 15 minutes before OA infusion and post-OA-CAPE group received CAPE 2 hours after OA administration. Malondialdehyde (MDA) level of plasma, bronchoalveolar lavage fluid (BALF), and lung tissue; myeloperoxidase activity of BALF and lung tissue; Na(+)-K(+) ATPase activity of lung tissue; and total protein content of BALF were measured. Light microscopic analyses of lung specimens were performed. The increased MDA levels in lung homogenates (47.98+/-13.75 nmol/mL), BALF (31.12+/-3.07 nmol/mL), and plasma (61.84+/-15.34 nmol/mL) decreased significantly to 24.33+/-3.09 nmol/mL (P = 0.000), 23.19+/-4.97 nmol/mL (P = 0.002), and 27.36+/-5.37 nmol/mL (P = 0.000), respectively, following CAPE administration in pre-OA-CAPE group. Another important finding was the restoration of the enzymatic activity of Na(+)-K(+) ATPase from a value of 203.89+/-32.18 nmol Pi/mg Protein/h in OA group, to a value of 302.17+/-51.90 nmol Pi/mg Protein/h (P = 0.012) in pre-OA-CAPE group with CAPE treatment. CAPE has been shown to have a clear attenuating effect on oxidative damage in experimental animal studies. However, further investigations are necessary to suggest CAPE as a treatment agent in critically ill patients with lung injury.
    Experimental Lung Research 07/2005; 31(5):483-96. · 1.47 Impact Factor
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    ABSTRACT: Apolipoprotein E (apo E) is directly involved in the amyloid deposition and fibril formation and is present in many cerebral and systemic amyloidoses immunologically. It is encoded by a polymorphic gene and it has three common alleles-epsilon2, epsilon3, and epsilon4. Exfoliation syndrome (XFS) is characterized by the deposition throughout the body of focal fibrillogranular aggregates in which there have been some reports of amyloid or amyloid-like features. We evaluated the possible association between apo E polymorphism and the occurrence of XFS. Using High Pure PCR Template Preparation Kits, genomic DNAs were extracted from whole blood and apo E polymorphisms were determined by using Lightcycler-Apo E Mutation Detection Kits in 76 patients with XFS and 74 controls. The E2/E2, E2/E3 and E2/E4 genotypes (OR 29.9, 95% CI 3.1-293.7; OR 56.1, 95% CI 12.5-252.7; OR 43.9, 95% CI 7.4-257.6, respectively) and the in2 allele are found to have an increased risk of developing XFS (p=0.0001); whereas the in3 allele was found to be protective (p=0.0001). Apo E polymorphism and the presence of in2 allele are seem to be significantly associated with the development of XFS.
    Experimental Eye Research 07/2005; 80(6):871-5. · 3.03 Impact Factor
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    ABSTRACT: The objective of this study was to investigate the effects of 3-aminobenzamide (3-AB) on tissue damage in lung after hind limb ischemia-reperfusion (I/R), by assessing blood biochemical assay and histopathological analysis. Thirty-five adult Wistar rats were divided into five groups. After application of anaesthesia both hind limbs were occluded with tourniquets. Following ischemia period for 60 min, the tourniquets were removed allowing reperfusion for 120 min. The IR group received 0.5 ml of saline while the IR+AB group received 3-AB (10 mgkg(-1) intraperitoneally). The IR+DMSO group was given 0.5 ml 10% DMSO 30 min before the removal of the tourniquets. The control group received 0.5 ml saline and the AB group received 0.5 ml 3-AB (10 mgkg(-1)) intraperitoneally. At the end of the reperfusion period, mid-line sternotomy was performed. Blood samples were taken with cardiac puncture. Bronchoalveolar lavage (BAL) of the left lung was performed with saline. Right lung was preserved for histopathological evaluation and biochemical examination. Lung tissue malondialdehyde (MDA) and 3-nitrotyrosine levels, myeloperoxidase and Na+/K+ ATP-ase activities, wet to dry weight ratios, and plasma and BAL fluid MDA levels were determined. Histopathological evaluation was performed, too. Hind limb IR caused significant increase in the lung tissue 3-NT to total tyrosine ratio (p = 0.014), wet to dry weight ratio (p = 0.000), MPO activity (p = 0.000), and MDA levels (p = 0.000). The animals treated with 3-AB showed a statistically significant decrease in these values (p < 0.05). Na+/K+ ATP-ase activity which was found to be decreased significantly with IR, returned to near normal levels with 3-AB treatment. Additionally, lung tissue injury in IR group characterized with moderate interstitial congestion and neutrophil infiltration, showed remarkable amelioration following 3-AB treatment. Our results strongly support the view that poly(ADP-ribose) polymerase (PARP) plays an important role in the inflammatory process in hind limb I/R-induced lung injury and as a PARP inhibitor, 3-AB seems to have a potential to treat this inflammatory injury.
    Pharmacological Research 06/2005; 51(5):453-62. · 4.35 Impact Factor
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    ABSTRACT: The possible contribution of Rho/Rho-kinase signalling in oleic acid (100 mg kg-1, i.v., for 4 h)-induced lung injury was investigated in rats. Furthermore, the possible protective effect of the administration of a Rho-kinase inhibitor, (+)-(R)-trans-4-(1-aminoethyl)-N-(4-pyridyl) cyclohexanecarboxamide dihydrochloride monohydrate (Y-27632, 0.5-5 mg kg-1, i.v., 15 min before the administration of oleic acid), was also examined. Western blot analysis as well as histopathological examination revealed that Rho-kinase (ROCK-1 and ROCK-2) was upregulated in lungs obtained from oleic acid-administrated rats. In addition, the markers of oxidative and nitrosative stress, i.e., malondialdehyde, myeloperoxidase, 3-nitro-L-tyrosine and nitrite/nitrate, in serum and lung tissue were also increased in the injury group. Treatment of rats with 5 mg kg-1 Y-27632 reversed the oleic acid-induced lung damage, which was demonstrated by histopathological assessment and confirmed in Western blot experiments: ROCK-blots were more intense in the oleic acid group than in control and Y-27632 treatment reversed ROCK upregulation. In addition, malondialdehyde, myeloperoxidase, 3-nitro-L-tyrosine and nitrite/nitrate were also normalized after the administration of Y-27632 (0.5 mg kg-1 and 5 mg kg-1). These findings suggest that ROCK-1 and ROCK-2 are involved in oleic acid-induced lung damage in rats, and that inhibition of this enzyme by Y-27632 may have a protective effect against such damage. Consequently, Rho kinase inhibitors may be potential therapeutic agents in the treatment of acute respiratory distress syndrome (ARDS).
    European Journal of Pharmacology 04/2005; 510(1-2):135-42. · 2.59 Impact Factor
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    ABSTRACT: The local ischemia-reperfusion (I/R) process gains a systemic nature and affects distal organs. The remote effects of I/R are most frequently observed in the lungs and pulmonary damage may vary from acute lung injury with mild dysfunction to severe respiratory failure or the acute respiratory distress syndrome. In this hind limb I/R induced experimental lung injury model two groups of rats as IR and ILO were determined. Both groups underwent 60 min of ischemia and 120 min of reperfusion. While ILO group received iloprost in saline, IR group received only saline before reperfusion period intravenously. Serum myeloperoxidase (MPO) activity, malondialdehyde (MDA) levels and total antioxidant capacity (TAC) and lung tissue MPO activity, MDA levels and Na+-K+ ATPase activity were measured and light microscopic analyses of lung specimens were performed. The MPO activities in serum and lung homogenates were found to be significantly decreased in ILO group (P < or = 0.01). The MDA levels in lung homogenates were found to be significantly decreased in ILO group (P < or = 0.01), but the decreases were not significant in serum MDA levels (P=0.052). Serum TAC and lung tissue Na+-K+ ATPase activity levels were found to be increased in ILO group compared to IR group (P < or = 0.01). Lung histology showed marked improvement by iloprost compared to the IR group in this study. Iloprost has been found to be effective in attenuating ischemia reperfusion-induced remote organ damage, in this case, lung injury, in rats.
    Pulmonary Pharmacology &amp Therapeutics 01/2005; 18(4):235-41. · 2.54 Impact Factor
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    ABSTRACT: Reactive oxygen species including hydroxyl radicals, superoxide anions and hydrogen peroxide which are produced by activated granulocytes play an essential role in many biochemical processes and diseases. Oxidant-mediated tissue damage may be important in the development of chronic sinusitis. The aim of this study was to investigate the serum levels of antioxidant vitamins and elements in 24 children (14 boys and 10 girls, age range: 7-12 years, mean age: 9.2 years) with chronic rhinosinusitis, compared to 20 age and sex matched healthy children. Blood samples were collected in the morning before breakfast and prior to any medication. Vitamin A, E and C levels were determined using reagent kits for high performance liquid chromatography. Cu, Zn and Mg levels were analyzed by atomic absorption spectrometry. Vitamin E, vitamin C, Cu and Zn levels were significantly lower in the patients group than in the control group. However, vitamin A and Mg levels did not differ. In conclusion, serum levels of antioxidant vitamins and elements may be important in the pathogenesis and treatment of chronic rhinosinusitis in children.
    Journal of Trace Elements in Medicine and Biology 02/2004; 18(2):189-92. · 1.96 Impact Factor
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    ABSTRACT: Reactive oxygen species have been implicated in pathogenesis injury after ischaemia-reperfusion (I/R). Caffeic Acid Phenethyl Ester (CAPE), an active component of honeybee propolis extract, exhibits antioxidant and anti-inflammatory properties. The aim of this study was to investigate the effects of CAPE on erythrocyte membrane damage after hind limb I/R. Rats were divided into two groups: I/R and I/R with CAPE pre-treatment. They were anaesthetized with intramuscular ketamine 100 mg kg(-1). A 4-h I/R period was performed on the right hind limb of all animals. In the CAPE-treated group, animals received CAPE 10 microm by intraperitoneal injection 1 h before the reperfusion. At the end of the reperfusion period, a midsternotomy was performed. A 5-ml blood sample was withdrawn from the ascending aorta for biochemical assays. Serum and erythrocyte membrane MDA levels were significantly lower in the CAPE-treated group when compared to the I/R group ( p = 0.001 and p<0.001, respectively). Erythrocyte membrane Na(+)-K(+) ATPases activity in the CAPE-treated group was significantly higher than the I/R group ( p<0.001). In conclusion, CAPE seems to be effective in protecting against oxidative stress. Therefore, we suggest that in order to decrease I/R injury, pre-administration of CAPE may be a promising agent for a variety of conditions associated with I/R.
    Cell Biochemistry and Function 01/2004; 22(5):287-90. · 1.85 Impact Factor