Hamit Hakan ALP

Prof. Hamit Hakan ALP


Research Focus & Metrics

Academic Career Length

19Years (2008-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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20 May 2009 in BMC Gastroenterology
Verified
Journal Article
Open access
PDF file
HDHakan Dursun
Hakan Dursun
MBMehmet Bilici
Mehmet Bilici
FAFatih Albayrak
Fatih Albayrak
COCengiz Ozturk
Cengiz Ozturk
MSMustafa B Saglam
Mustafa B Saglam
HSHalis Suleyman
Halis Suleyman
Background: Although many drugs are available for the treatment of gastric ulcers, often these drugs are ineffective. Many antidepressant drugs have been shown to have antiulcer activity in various models of experimental ulcer. One such drug, the antidepressant mirtazapine, has been reported to have an antiulcer effect that involves an increase in antioxidant, and a decrease in oxidant, parameters. To date, however, there is no information available regarding the antiulcer activity for a similar antidepressant, fluvoxamine. This study aimed to investigate the antiulcer effects of fluvoxamine and to determine its relationship with antioxidants. Methods: Groups of rats fasted for 24 h received fluvoxamine (25, 50, 100 and 200 mg/kg), ranitidine (50 mg/kg) or distilled water by oral gavage. Indomethacin (25 mg/kg) was orally administered to the rats as an ulcerative agent. Six hours after ulcer induction, the stomachs of the rats were excised and an ulcer index determined. Separate groups of rats were treated with the same doses of fluvoxamine and ranitidine, but not with indomethacin, to test effects of these drugs alone on biochemical parameters. The stomachs were evaluated biochemically to determine oxidant and antioxidant parameters. We used one-way ANOVA and least significant difference (LSD) options for data analysis. Results: The 25, 50, 100 and 200 mg/kg doses of fluvoxamine exerted antiulcer effects of 48.5, 67.5, 82.1 and 96.1%, respectively, compared to the control rat group. Ranitidine showed an 86.5% antiulcer effect. No differences were observed in the absence of indomethacin treatment for any dose of fluvoxamine or for ranitidine. The levels of antioxidant parameters, total glutathione and nitric oxide, were increased in all fluvoxamine groups and in the ranitidine group when compared with the indomethacin-only group. In addition, fluvoxamine and ranitidine decreased the levels of the oxidant parameters, myeloperoxidase and malondialdeyhyde, in the stomach tissues of the rats when compared to indomethacin group. Conclusion: We conclude that fluvoxamine has antiulcer effects, and that these occur by a mechanism that involves activation of antioxidant parameters and inhibition of some toxic oxidant parameters.

1 January 2012 in International Journal of Medical Sciences
Verified
Journal Article
Open access
YKYüksel Kaya
Yüksel Kaya
AÇAyşegül ÇEBİ
Ayşegül ÇEBİ
NSNihat Söylemez
Nihat Söylemez
HDHalit Demi̇r
Halit Demi̇r
HAHamit Hakan ALP
Hamit Hakan ALP
EBEbubekir Bakan
Ebubekir Bakan
The correlation of coronary artery disease (CAD) with pro-oxidant/antioxidant balance and oxidative DNA damage was investigated. Seventy-seven patients with CAD and 44 healthy individuals as control were included in this study. The comparative ratios of ubiquinol-10/ubiquinone-10, 8-hydroxy-2(')-deoxyguanosine/deoxyguanosine and the level of MDA measured by HPLC and the activities of GPX and SOD by colorimetric approach in blood samples obtained from patients with CAD were unraveled.8-OHdG/dG ratios, serum MDA level and GPX activity were found significantly elevated level in serum of CAD patients compared to control group. The SOD activity was observed in stable levels in CAD patients. Ubiquinol-10/ubiquinone-10 ratio was significantly lower in patients with CAD than the controls. The positive correlation was observed between 8-OHdG/dG ratios in both MDA levels and GPX activity, while the significant negative correlation was seemed between the ratio of 8-OHdG/dG and ubiquinol-10/ubiquinone-10 as well as MDA levels and ubiquinol-10/ubiquinone-10 ratio. We conclude that, both the disruption of pro-oxidant/antioxidant balance and oxidative stress in DNA may play an important role in the pathogenesis of coronary artery disease.

31 March 2010 in Chemico-Biological Interactions
Verified
Journal Article
Closed access
BPBeyzagul Polat
Beyzagul Polat
HSHalis Suleyman
Halis Suleyman
HAHamit Hakan ALP
Hamit Hakan ALP

1 January 2009 in The Tohoku Journal of Experimental Medicine
Verified
Journal Article
Open access
PDF file
OAOrhan Ates
Orhan Ates
SASedat Azizi
Sedat Azizi
HAHamit Hakan ALP
Hamit Hakan ALP
AKAhmet Kiziltunc
Ahmet Kiziltunc
SBSukru Beydemir
Sukru Beydemir
OBOrhan Baykal
Orhan Baykal
Age-related macular degeneration (AMD) is one of the most common causes of vision loss. AMD has been classified into two forms: atrophic and exudative forms. The exudative form is associated with choroidal neovascularization of the subretinal macular region, resulting in a sudden loss of central vision. However, the exact cause of AMD remains unknown. Several risk factors have been postulated, including smoking, atherosclerosis, and low levels of antioxidant enzymes. Malondialdehyde (MDA), a lipid peroxidation product, is used as a marker of oxidative stress. Paraoxonase 1 (PON1) metabolizes lipid peroxides and prevents oxidation of low-density lipoprotein. Increased levels of homocysteine may cause vascular endothelial injury by releasing free radicals. The purpose of this study is to investigate the relationships between serum PON1 activity and the serum levels of homocysteine and MDA in AMD. Forty patients with exudative-type AMD (63.3 ± 5 years) and 40 controls (61± 4 years) were assessed in a cross-sectional study. The serum PON1 activity was significantly lower in the patients with AMD than that in the controls (p < 0.001). In contrast, the serum levels of MDA and homocysteine were significantly higher in the patients than those in the controls (p < 0.001, for both). In AMD patients, significant negative correlation was found between PON1 activity and MDA level (r = −0.493, p < 0.05) and between PON1 activity and homocysteine level (r = −0.557, p < 0.05). Increased serum homocysteine and MDA levels may be responsible for the decreased PON1 activity in patients with AMD.

29 November 2010 in Acta Ophthalmologica
Verified
Journal Article
Closed access
PDF file
OAOrhan Ates
Orhan Ates
HAHamit Hakan ALP
Hamit Hakan ALP
IKIbrahim Kocer
Ibrahim Kocer
OBOrhan Baykal
Orhan Baykal
ISİlKnur A. Salman
İlKnur A. Salman

24 November 2015 in Respiratory Care
Verified
Journal Article
Open access
PDF file
ASAysel Sunnetcioglu
Aysel Sunnetcioglu
HAHamit Hakan ALP
Hamit Hakan ALP
BSBunyamin Sertogullarından
Bunyamin Sertogullarından
RBRagip Balaharoglu
Ragip Balaharoglu
HGHulya Gunbatar
Hulya Gunbatar
BACKGROUND: Oxidative damage is a major contributing factor to carcinogenesis and obstructive disorders in lungs. Current evidence suggests that the inflammatory processes yield to oxidative mechanisms, which underlie COPD, lung cancer, and obstructive sleep apnea syndrome (OSAS). This study aimed to evaluate the oxidative damage in these diseases by evaluating the oxidative and antioxidant biomarkers. METHODS: Malondialdehyde, 8-oxo-7,8-dihydro-2′-deoxyguanosine, and coenzyme Q10 levels were evaluated in the blood samples of subjects with COPD, lung cancer, and OSAS by high-pressure liquid chromatography. RESULTS: A total of 111 participants (35 females, 76 males) with OSAS ( n = 29), COPD ( n = 26), and lung cancer ( n = 28) and healthy controls ( n = 28) were included in the study. The malondialdehyde and coenzyme Q10 levels were significantly higher in all 3 diseases when compared with controls ( P < .01), whereas 8-oxo-7,8-dihydro-2′-deoxyguanosine levels were only significantly higher than in healthy controls in subjects with lung cancer ( P = .005). The highest levels of malondialdehyde and coenzyme Q10 were determined in subjects with OSAS and lung cancer, respectively. The highest 8-oxo-7,8-dihydro-2′-deoxyguanosine levels were also observed in subjects with lung cancer, but the differences of this biomarker with other diagnoses were not statistically significant ( P = .56). CONCLUSION: Oxidative damage was observed in all 3 diagnoses, and, as a response to oxidative stress, antioxidant mechanisms were also active in these diseases. Malondialdehyde and 8-oxo-7,8-dihydro-2′-deoxyguanosine were found to be efficiently usable in the evaluation of oxidative damage in chronic respiratory diseases. (ClinicalTrials.gov registration NCT02406053.)