Objectives The aim of this study is to evaluate the protective effect of nicorandil, a selective ... more Objectives The aim of this study is to evaluate the protective effect of nicorandil, a selective mitochondrial KATP channel opener, on QT prolongation and myocardial damage induced by amitriptyline. Methods The dose of amitriptyline (intraperitoneal, i.p.) that prolong the QT interval was found 75 mg/kg. Rats were randomized into five groups the control group, amitriptyline group, nicorandil (selective mitochondrial KATP channel opener, 3 mg/kg i.p.) + amitriptyline group, 5-hdyroxydecanoate (5-HD, selective mitochondrial KATP channel blocker, 10 mg/kg i.p.) + amitriptyline group and 5-HD + nicorandil + amitriptyline group. Cardiac parameters, biochemical and histomorphological/immunohistochemical examinations were evaluated. p < 0.05 was accepted as statistically significant. Key findings Amitriptyline caused statistically significant prolongation of QRS duration, QT interval and QTc interval (p < 0.05). It also caused changes in tissue oxidant (increase in malondialdehyde)/a...
Our aim was to investigate the protective effect of wheat germ oil (WGO) at different doses on di... more Our aim was to investigate the protective effect of wheat germ oil (WGO) at different doses on diabetes mellitus (DM)-induced erectile and endothelial dysfunction. Twenty-four male Wistar rats weighing 250–300 g were divided into four groups as; control group treated with saline, DM group, DM group treated with 3 ml/kg WGO (DM + 3WGO group), DM group treated with 6 ml/kg WGO. Type 1 DM was induced by intraperitoneal injection of 60 mg/kg streptozotocin (STZ). STZ-induced diabetic rats received saline, 3 ml/kg WGO, and 6 ml/kg WGO via oral gavage daily for 5 weeks. The density of WGO used was 0.92 g/ml. The protective effect of WGO was evaluated by (i) in vitro vascular function, (ii) in vivo erectile function, and (iii) oxidative stress parameters in both aorta and penile tissue. Acetylcholine-mediated relaxation in the aorta and erectile functions decreased significantly in the DM group (p = 0.018 and p = 0.005). WGO (3 and 6 ml/kg) improved vascular functions in the DM groups (p = 0.001 and p = 0.014). The beneficial effect of WGO on erectile function appeared at higher doses of WGO. However, a higher dose of WGO substantially increased the oxidative stress parameters in both aorta and penile tissue. These findings suggest that the improvement in vascular or erectile function by WGO was not related to antioxidant effects, and new studies are needed to clarify the mechanism.
Peritoneal Dialysis International: Journal of the International Society for Peritoneal Dialysis, 2007
BackgroundBacterial peritonitis episodes may disturb the functional and histological integrity of... more BackgroundBacterial peritonitis episodes may disturb the functional and histological integrity of the peritoneum in peritoneal dialysis patients. The renin–angiotensin–aldosterone system may have fibrotic effects on the peritoneum.ObjectiveTo study the effects of an angiotensin II receptor antagonist (irbesartan) and an aldosterone antagonist (spironolactone) in the prevention of peritoneal fibrosis in a rat model of bacterial peritonitis.Methods40 Wistar rats were randomized into 5 groups: bacteria (B), bacteria–irbesartan (BI), bacteria–spironolactone (BS), bacteria–irbesartan–spironolactone (BIS), and control (C) groups. The C group received only dextran beads (Cytodex; Sigma Chemicals, St Louis, Missouri, USA); the others were given bacteria and dextran beads intraperitoneally. Irbesartan and/or spironolactone were given to 3 groups: BI, BS, and BIS. On the eighth day, the rats were sacrificed, peritoneal adhesion was quantified, and peritoneal tissue sections were evaluated his...
The 2nd International Cell Death Research Congress, 2018
Human SH-SY5Y cell line has been used as an in vitro model in neuroscience research. However, man... more Human SH-SY5Y cell line has been used as an in vitro model in neuroscience research. However, many researchers emphasized that there are many differences between differentiated and undifferentiated characteristics of SH-SY5Y. Although Retinoic Acid (RA) generally have been used for differentiation of SH-SY5Y cells, which protocol provides better differentiation have not been cleared yet. Therefore, we compared RA and the other mediums in different treatment periods for obtaining better differentiated, carrying a neuron-like phenotype (N-type) characteristics, of SH-SY5Y human cells. The cells were pre-treated with different mediums for different treatment periods and compared with both for each other and the control group. When we pre-treated the cells with RA for 5-day and followed by the Mix medium (Neurobasal, B27, db-cAMP, KCI) and BDNF, neurite length and MAP2 expression of the cells were found significantly higher than the control group. In conclusion, we showed that more than...
Background:Brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic fact... more Background:Brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF) have essential roles in synaptic plasticity which is involved in pathogenesis and treatment of psychiatric disorders. However, it is not clear whether they act simultaneously during illness states in major psychiatric disorders.Methods:BDNF and GDNF serum levels were measured concomitantly by enzyme-linked immunosorbent assay (ELISA) method in 171 patients diagnosed with schizophrenia (n= 33), bipolar disorder-manic episode (n= 39), bipolar/unipolar depression (n= 64, 24/40) and obsessive-compulsive disorder (n= 35) according to DSM-IV, and 78 healthy volunteers. SCID-I and SCID non-patient version were used for clinical evaluation of the patients and healthy volunteers, respectively. Correlations between the two trophic factor levels, and illness severity scores, duration of illness and medication dosages were studied across different illnesses.Results:While patients had equal...
Brain-derived neurotrophic factor (BDNF) has been consistently reported to be decreased in mania ... more Brain-derived neurotrophic factor (BDNF) has been consistently reported to be decreased in mania or depression in bipolar disorders. Evidence suggests that Glial cell line-derived neurotrophic factor (GDNF) has a role in the pathogenesis of mood disorders. Whether GDNF and BDNF act in the same way across different episodes in bipolar disorders is unclear. BDNF and GDNF serum levels were measured simultaneously by enzyme-linked immunosorbent assay (ELISA) method in 96 patients diagnosed with bipolar disorder according to DSM-IV (37 euthymic, 33 manic, 26 depressed) in comparison to 61 healthy volunteers. SCID- I and SCID-non patient version were used for clinical evaluation of the patients and healthy volunteers respectively. Correlations between the two trophic factor levels, and medication dose, duration and serum levels of lithium or valproate were studied across different episodes of illness. Patients had significantly lower BDNF levels during mania and depression compared to euthymic patients and healthy controls. GDNF levels were not distinctive. However GDNF/BDNF ratio was higher in manic state compared to euthymia and healthy controls. Significant negative correlation was observed between BDNF and GDNF levels in euthymic patients. While BDNF levels correlated positively, GDNF levels correlated negatively with lithium levels. Regression analysis confirmed that lithium levels predicted only GDNF levels positively in mania, and negatively in euthymia. Small sample size in different episodes and drug-free patients was the limitation of thestudy. Current data suggests that lithium exerts its therapeutic action by an inverse effect on BDNF and GDNF levels, possibly by up-regulating BDNF and down-regulating GDNF to achieve euthymia.
Objectives: Endothelial dysfunction contributes to the development of atherosclerosis in diabetic... more Objectives: Endothelial dysfunction contributes to the development of atherosclerosis in diabetic subjects. Endothelin-1 (ET-1) is an endothelium derived vasoconstrictor. It has been shown that ET-1 levels are increased in a variety of situations such as diabetes, hypertension and ...
Purpose To investigate the Macular Pigment Optical Density (MPOD) differences between a northern ... more Purpose To investigate the Macular Pigment Optical Density (MPOD) differences between a northern European and a Mediterranean population. Methods MPOD was measured psychophysically using Heterochromatic Flicker Photometry in 71 healthy subjects from northern Europe (18 Dutch and 53 British). 74 healthy age‐matched Cretans (Greece) underwent the same measurements according to the same protocol. None of the subjects was taking any carotenoids supplements. The comparison of MPOD between the two populations was statistically assessed with a Generalized Linear Model of regression. The effect of age and gender was taken into consideration. Results The mean MPOD of the northern Europe population was 0.43 (CI 95% 0.39‐0.47) and the mean age 45 years old (±19). No effect of age (p=0.402) or gender (p=0.074) was revealed into this group. Respectively, for the Mediterranean population the mean MPOD was 0.42 (CI 95% 0.38‐0.45) and the mean age 39 years old (±17);mean MPOD of this group didn’t s...
Cbu Beden Egitimi Ve Spor Bilimleri Dergisi, Oct 9, 2014
Bu calismada E vitamininin anaerobik esik civarinda kosulan standart egzersizde yorgunlugun gecik... more Bu calismada E vitamininin anaerobik esik civarinda kosulan standart egzersizde yorgunlugun geciktirilmesindeki etkisi plazma laktat konsantrasyonlari (PLa) temel alinarak, oksidasyon mekanizmalari uzerindeki etkisi sulfhidril gruplari (RSH), ve lipid peroksidasyon urunleri (TBARS) incelenerek degerlendirildi. Arastirmaya katilan yaslari 19.8±1.3 olan 8 subelit gonullu sporcudan istirahat ve standart kosu egzersizi programi sonrasinda; 1) Herhangi bir ilac kullanmadan, 2) 1 haftalik plasebo kullanimindan sonra, 3) 1 haftalik 1000 UI/gun dozunda E vitamini kullanimi sonrasinda PLa, serumda E vitamini, RSH ve TBARS konsantrasyonlari calisildi. 1 haftalik 1000 UI/gun dozunda E vitamini desteginin serum E vitamini duzeyini % 75.9 oraninda arttirdigi gozlendi. Plasebo kullaniminin calisilan hicbir parametre uzerine anlamli etkisi gorulmedi. E vitamini kullanimi oncesinde egzersizin serum TBARS duzeyini anlamli sekilde arttirdigi (p<0.05) ancak, E vitamini kullanimi sonrasinda bu artis oraninda anlamli bir azalma oldugu saptandi (p<0.05). Egzersizin ve E vitamini kullaniminin serum RSH duzeyine anlamli bir etkisi olmadigi tespit edildi. E vitamini kullanimi ile standart kosu egzersizi sonrasinda PLa duzeyinin 4.7±0.7 mM'den 4.3±1.5 mM'e azalmasina ve serum E vitamini duzeyi ile PLa konsantrasyonlari arasinda negatif korelasyon saptanmasina ragmen bu fark ve iliski istatistiksel olarak anlamli degildi.
Objectives The aim of this study is to evaluate the protective effect of nicorandil, a selective ... more Objectives The aim of this study is to evaluate the protective effect of nicorandil, a selective mitochondrial KATP channel opener, on QT prolongation and myocardial damage induced by amitriptyline. Methods The dose of amitriptyline (intraperitoneal, i.p.) that prolong the QT interval was found 75 mg/kg. Rats were randomized into five groups the control group, amitriptyline group, nicorandil (selective mitochondrial KATP channel opener, 3 mg/kg i.p.) + amitriptyline group, 5-hdyroxydecanoate (5-HD, selective mitochondrial KATP channel blocker, 10 mg/kg i.p.) + amitriptyline group and 5-HD + nicorandil + amitriptyline group. Cardiac parameters, biochemical and histomorphological/immunohistochemical examinations were evaluated. p < 0.05 was accepted as statistically significant. Key findings Amitriptyline caused statistically significant prolongation of QRS duration, QT interval and QTc interval (p < 0.05). It also caused changes in tissue oxidant (increase in malondialdehyde)/a...
Our aim was to investigate the protective effect of wheat germ oil (WGO) at different doses on di... more Our aim was to investigate the protective effect of wheat germ oil (WGO) at different doses on diabetes mellitus (DM)-induced erectile and endothelial dysfunction. Twenty-four male Wistar rats weighing 250–300 g were divided into four groups as; control group treated with saline, DM group, DM group treated with 3 ml/kg WGO (DM + 3WGO group), DM group treated with 6 ml/kg WGO. Type 1 DM was induced by intraperitoneal injection of 60 mg/kg streptozotocin (STZ). STZ-induced diabetic rats received saline, 3 ml/kg WGO, and 6 ml/kg WGO via oral gavage daily for 5 weeks. The density of WGO used was 0.92 g/ml. The protective effect of WGO was evaluated by (i) in vitro vascular function, (ii) in vivo erectile function, and (iii) oxidative stress parameters in both aorta and penile tissue. Acetylcholine-mediated relaxation in the aorta and erectile functions decreased significantly in the DM group (p = 0.018 and p = 0.005). WGO (3 and 6 ml/kg) improved vascular functions in the DM groups (p = 0.001 and p = 0.014). The beneficial effect of WGO on erectile function appeared at higher doses of WGO. However, a higher dose of WGO substantially increased the oxidative stress parameters in both aorta and penile tissue. These findings suggest that the improvement in vascular or erectile function by WGO was not related to antioxidant effects, and new studies are needed to clarify the mechanism.
Peritoneal Dialysis International: Journal of the International Society for Peritoneal Dialysis, 2007
BackgroundBacterial peritonitis episodes may disturb the functional and histological integrity of... more BackgroundBacterial peritonitis episodes may disturb the functional and histological integrity of the peritoneum in peritoneal dialysis patients. The renin–angiotensin–aldosterone system may have fibrotic effects on the peritoneum.ObjectiveTo study the effects of an angiotensin II receptor antagonist (irbesartan) and an aldosterone antagonist (spironolactone) in the prevention of peritoneal fibrosis in a rat model of bacterial peritonitis.Methods40 Wistar rats were randomized into 5 groups: bacteria (B), bacteria–irbesartan (BI), bacteria–spironolactone (BS), bacteria–irbesartan–spironolactone (BIS), and control (C) groups. The C group received only dextran beads (Cytodex; Sigma Chemicals, St Louis, Missouri, USA); the others were given bacteria and dextran beads intraperitoneally. Irbesartan and/or spironolactone were given to 3 groups: BI, BS, and BIS. On the eighth day, the rats were sacrificed, peritoneal adhesion was quantified, and peritoneal tissue sections were evaluated his...
The 2nd International Cell Death Research Congress, 2018
Human SH-SY5Y cell line has been used as an in vitro model in neuroscience research. However, man... more Human SH-SY5Y cell line has been used as an in vitro model in neuroscience research. However, many researchers emphasized that there are many differences between differentiated and undifferentiated characteristics of SH-SY5Y. Although Retinoic Acid (RA) generally have been used for differentiation of SH-SY5Y cells, which protocol provides better differentiation have not been cleared yet. Therefore, we compared RA and the other mediums in different treatment periods for obtaining better differentiated, carrying a neuron-like phenotype (N-type) characteristics, of SH-SY5Y human cells. The cells were pre-treated with different mediums for different treatment periods and compared with both for each other and the control group. When we pre-treated the cells with RA for 5-day and followed by the Mix medium (Neurobasal, B27, db-cAMP, KCI) and BDNF, neurite length and MAP2 expression of the cells were found significantly higher than the control group. In conclusion, we showed that more than...
Background:Brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic fact... more Background:Brain-derived neurotrophic factor (BDNF) and glial cell line-derived neurotrophic factor (GDNF) have essential roles in synaptic plasticity which is involved in pathogenesis and treatment of psychiatric disorders. However, it is not clear whether they act simultaneously during illness states in major psychiatric disorders.Methods:BDNF and GDNF serum levels were measured concomitantly by enzyme-linked immunosorbent assay (ELISA) method in 171 patients diagnosed with schizophrenia (n= 33), bipolar disorder-manic episode (n= 39), bipolar/unipolar depression (n= 64, 24/40) and obsessive-compulsive disorder (n= 35) according to DSM-IV, and 78 healthy volunteers. SCID-I and SCID non-patient version were used for clinical evaluation of the patients and healthy volunteers, respectively. Correlations between the two trophic factor levels, and illness severity scores, duration of illness and medication dosages were studied across different illnesses.Results:While patients had equal...
Brain-derived neurotrophic factor (BDNF) has been consistently reported to be decreased in mania ... more Brain-derived neurotrophic factor (BDNF) has been consistently reported to be decreased in mania or depression in bipolar disorders. Evidence suggests that Glial cell line-derived neurotrophic factor (GDNF) has a role in the pathogenesis of mood disorders. Whether GDNF and BDNF act in the same way across different episodes in bipolar disorders is unclear. BDNF and GDNF serum levels were measured simultaneously by enzyme-linked immunosorbent assay (ELISA) method in 96 patients diagnosed with bipolar disorder according to DSM-IV (37 euthymic, 33 manic, 26 depressed) in comparison to 61 healthy volunteers. SCID- I and SCID-non patient version were used for clinical evaluation of the patients and healthy volunteers respectively. Correlations between the two trophic factor levels, and medication dose, duration and serum levels of lithium or valproate were studied across different episodes of illness. Patients had significantly lower BDNF levels during mania and depression compared to euthymic patients and healthy controls. GDNF levels were not distinctive. However GDNF/BDNF ratio was higher in manic state compared to euthymia and healthy controls. Significant negative correlation was observed between BDNF and GDNF levels in euthymic patients. While BDNF levels correlated positively, GDNF levels correlated negatively with lithium levels. Regression analysis confirmed that lithium levels predicted only GDNF levels positively in mania, and negatively in euthymia. Small sample size in different episodes and drug-free patients was the limitation of thestudy. Current data suggests that lithium exerts its therapeutic action by an inverse effect on BDNF and GDNF levels, possibly by up-regulating BDNF and down-regulating GDNF to achieve euthymia.
Objectives: Endothelial dysfunction contributes to the development of atherosclerosis in diabetic... more Objectives: Endothelial dysfunction contributes to the development of atherosclerosis in diabetic subjects. Endothelin-1 (ET-1) is an endothelium derived vasoconstrictor. It has been shown that ET-1 levels are increased in a variety of situations such as diabetes, hypertension and ...
Purpose To investigate the Macular Pigment Optical Density (MPOD) differences between a northern ... more Purpose To investigate the Macular Pigment Optical Density (MPOD) differences between a northern European and a Mediterranean population. Methods MPOD was measured psychophysically using Heterochromatic Flicker Photometry in 71 healthy subjects from northern Europe (18 Dutch and 53 British). 74 healthy age‐matched Cretans (Greece) underwent the same measurements according to the same protocol. None of the subjects was taking any carotenoids supplements. The comparison of MPOD between the two populations was statistically assessed with a Generalized Linear Model of regression. The effect of age and gender was taken into consideration. Results The mean MPOD of the northern Europe population was 0.43 (CI 95% 0.39‐0.47) and the mean age 45 years old (±19). No effect of age (p=0.402) or gender (p=0.074) was revealed into this group. Respectively, for the Mediterranean population the mean MPOD was 0.42 (CI 95% 0.38‐0.45) and the mean age 39 years old (±17);mean MPOD of this group didn’t s...
Cbu Beden Egitimi Ve Spor Bilimleri Dergisi, Oct 9, 2014
Bu calismada E vitamininin anaerobik esik civarinda kosulan standart egzersizde yorgunlugun gecik... more Bu calismada E vitamininin anaerobik esik civarinda kosulan standart egzersizde yorgunlugun geciktirilmesindeki etkisi plazma laktat konsantrasyonlari (PLa) temel alinarak, oksidasyon mekanizmalari uzerindeki etkisi sulfhidril gruplari (RSH), ve lipid peroksidasyon urunleri (TBARS) incelenerek degerlendirildi. Arastirmaya katilan yaslari 19.8±1.3 olan 8 subelit gonullu sporcudan istirahat ve standart kosu egzersizi programi sonrasinda; 1) Herhangi bir ilac kullanmadan, 2) 1 haftalik plasebo kullanimindan sonra, 3) 1 haftalik 1000 UI/gun dozunda E vitamini kullanimi sonrasinda PLa, serumda E vitamini, RSH ve TBARS konsantrasyonlari calisildi. 1 haftalik 1000 UI/gun dozunda E vitamini desteginin serum E vitamini duzeyini % 75.9 oraninda arttirdigi gozlendi. Plasebo kullaniminin calisilan hicbir parametre uzerine anlamli etkisi gorulmedi. E vitamini kullanimi oncesinde egzersizin serum TBARS duzeyini anlamli sekilde arttirdigi (p<0.05) ancak, E vitamini kullanimi sonrasinda bu artis oraninda anlamli bir azalma oldugu saptandi (p<0.05). Egzersizin ve E vitamini kullaniminin serum RSH duzeyine anlamli bir etkisi olmadigi tespit edildi. E vitamini kullanimi ile standart kosu egzersizi sonrasinda PLa duzeyinin 4.7±0.7 mM'den 4.3±1.5 mM'e azalmasina ve serum E vitamini duzeyi ile PLa konsantrasyonlari arasinda negatif korelasyon saptanmasina ragmen bu fark ve iliski istatistiksel olarak anlamli degildi.
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