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Featured researches published by Seyfettin Gür.


Clinical Nutrition | 2008

Effects of pomegranate juice consumption on sperm quality, spermatogenic cell density, antioxidant activity and testosterone level in male rats

Gaffari Türk; Mustafa Sönmez; Muhterem Aydin; Abdurrauf Yüce; Seyfettin Gür; Murat Yuksel; Emrah Hicazi Aksu; Hakan Aksoy

BACKGROUND & AIM Pomegranate fruit is inescapably linked with fertility, birth and eternal life because of its many seeds. The aim of this study was to investigate the effects of pomegranate juice (PJ) consumption on sperm quality, spermatogenic cell density, antioxidant activity and testosterone level of male healthy rats. METHODS Twenty-eight healthy adult male Wistar rats were divided into four groups; each group containing seven rats. One milliliter distilled water, 0.25 mL PJ plus 0.75 mL distilled water, 0.50 mL PJ plus 0.50 mL distilled water and 1 mL PJ were given daily for seven weeks by gavage to rats in the first, second, third and fourth groups, respectively. Body and reproductive organ weights, spermatogenic cell density, sperm characteristics, levels of antioxidant vitamins, testosterone, and lipid peroxidation and, antioxidant enzyme activities were investigated. All analyses were done only once at the end of the seven week study period. Data were compared by analysis of variance (ANOVA) and the degree of significance was set at P<0.05. RESULTS A significant decrease in malondialdehyde (MDA) level and marked increases in glutathione (GSH), glutathione peroxidase (GSH-Px) and catalase (CAT) activities, and vitamin C level were observed in rats treated with different doses of PJ. PJ consumption provided an increase in epididymal sperm concentration, sperm motility, spermatogenic cell density and diameter of seminiferous tubules and germinal cell layer thickness, and it decreased abnormal sperm rate when compared to the control group. CONCLUSION The results suggest that PJ consumption improves sperm quality and antioxidant activity of rats.


Toxicology | 2011

Protective effects of nanostructures of hydrated C60 fullerene on reproductive function in streptozotocin-diabetic male rats

Ramazan Bal; Gaffari Türk; Mehmet Tuzcu; Ökkeş Yilmaz; Ibrahim Hanifi Ozercan; Tuncay Kuloglu; Seyfettin Gür; Victor S. Nedzvetsky; Artem A. Tykhomyrov; Grigory V. Andrievsky; Giyasettin Baydas; Mustafa Nazıroğlu

Diabetes mellitus is a well-recognized cause of male sexual dysfunction and impairments of male fertility. Streptozotocin (STZ) is used for medical treatment of neoplastic islet β-cells of pancreas and producing of animal model of diabetes mellitus type 1 that is characterized by suppression of reproductive activity due to the hyperglycaemia-induced oxidative stress and histopathological alterations in testes. Seeking for the agents that could alleviate diabetes-induced damage to reproductive system is yet the important area of inquiry. The present study was designed to evaluate whether hydrated C(60) fullerene (C(60)HyFn), which is known to be powerful bioantioxidant, eliminate testicular dysfunction induced by STZ-diabetes in rats. Wistar strain male albino rats were divided into four groups of six animals each: (1) control group, (2) C(60)HyFn-treated nondiabetic group, (3) STZ-diabetic group and (4) C(60)HyFn-treated diabetic group. Once hyperglycaemia was induced by STZ, rats in the second and fourth groups were treated with C(60)HyFn (in the form of drinking water) at the dose of 4μg/kg daily for 5 weeks. In diabetic rats, relative weights of right cauda epididymis, seminal vesicles, prostate, sperm motility and epididymal sperm concentration were significantly less than those of control group, but which were restored in the fourth group treated with C(60)HyFn (p<0.001). In hematoxylin and eosin staining, marked histopathological changes including degeneration, desquamation, disorganisation and reduction in germinal cells, interstitial oedema and congestion were evident in the testis of diabetic rats, but C(60)HyFn treatment resulted in recovery of histopathological changes and an increase in Johnsens testicular score significantly (p<0.001). C(60)HyFn treatment restores the increased apoptosis induced by STZ-diabetes. In diabetic rats, levels of serum testosterone, testicular reduced glutathione (GSH) and alpha-tocopherol were significantly reduced and testicular lipid peroxidation level was increased (p<0.001). Nevertheless, treatment of diabetic rats with C(60)HyFn resulted in significant corrective effects on these parameters towards the control levels. C(60)HyFn, applied alone, did not exert any toxic effects in testicular tissues. Furthermore, C(60)HyFn treatment in diabetic and nondiabetic rats resulted in considerable elevations of some important polyunsaturated fatty acids. In conclusion, we have presented for the first time substantial evidence that administration of C(60)HyFn significantly reduces diabetes-induced oxidative stress and associated complications such as testicular dysfunction and spermatogenic disruption.


Journal of Environmental Science and Health Part B-pesticides Food Contaminants and Agricultural Wastes | 2012

Assessment of imidacloprid toxicity on reproductive organ system of adult male rats.

Ramazan Bal; Gaffari Türk; Mehmet Tuzcu; Ökkeş Yilmaz; Tuncay Kuloglu; Ramazan Gundogdu; Seyfettin Gür; Ali Agca; Mustafa Ulas; Zafer Çambay; Zeynep Tuzcu; Hasan Gencoglu; Mehmet Güvenç; Ayse Dilek Ozsahin; Nevin Kocaman; Abdullah Aslan; Ebru Etem

In the current study it was aimed to investigate the toxicity of low doses of imidacloprid (IMI) on the reproductive organ systems of adult male rats. The treatment groups received 0.5 (IMI-0.5), 2 (IMI-2) or 8 mg IMI/kg body weight by oral gavage (IMI-8) for three months. The deterioration in sperm motility in IMI-8 group and epidydimal sperm concentration in IMI-2 and IMI-8 groups and abnormality in sperm morphology in IMI-8 were significant. The levels of testosterone (T) and GSH decreased significantly in group IMI-8 compared to the control group. Upon treatment with IMI, apoptotic index increased significantly only in germ cells of the seminiferous tubules of IMI-8 group when compared to control. Fragmentation was striking in the seminal DNA from the IMI-8 group, but it was much less obvious in the IMI-2 one. IMI exposure resulted in elevation of all fatty acids analyzed, but the increases were significant only in stearic, oleic, linoleic and arachidonic acids. The ratios of 20:4/20:3 and 20:4/18:2 were decreased and 16:1n-9/16:0 ratio was increased. In conclusion, the present animal experiments revealed that the treatment with IMI at NOAEL dose-levels caused deterioration in sperm parameters, decreased T level, increased apoptosis of germ cells, seminal DNA fragmentation, the depletion of antioxidants and change in disturbance of fatty acid composition. All these changes indicate the suppression of testicular function.


Reproduction in Domestic Animals | 2008

Effect of Exogenous GnRH at the Time of Artificial Insemination on Reproductive Performance of Awassi Ewes Synchronized with Progestagen–PMSG–PGF2α Combination

Gaffari Türk; Seyfettin Gür; Mustafa Sönmez; Tanzer Bozkurt; Emrah Hicazi Aksu; H Aksoy

This study was carried out to investigate the efficacy of PGF(2alpha) for oestrus synchronization (ES) in Awassi ewes to which were administered the progestagen-PMSG combination, and to evaluate the effect of the exogenous GnRH administration immediately after the artificial insemination (AI) on their pregnancy rate and lambing performance during the breeding season. The ewes (n = 33) were treated with an intravaginal sponge impregnated with 30 mg fluorogestane acetate for 12 days and were injected with 500 IU PMSG at the time of removal of the sponge. The ewes were then divided into three equal groups of 11 ewes each. One millilitre of physiological saline (0.9% NaCl; placebo) was administered to each ewe in Group 1 at the time of second AI. Approximately 4 microg GnRH (busereline) was injected to each ewe in Group 2 immediately after second AI. A total of 150 microg PGF(2alpha) (cloprostenole) was injected at the time of sponge removal on day 12 and 4 microg GnRH immediately after the second AI was also treated to each ewe in Group 3. Intracervical AI with diluted fresh semen was performed twice at 12 and 24 h following the onset of oestrus. The injection-oestrus onset and injection-oestrus-end interval in Group 3 was significantly (p < 0.001) shorter than both Groups 1 and 2. Although the pregnancy rates of Groups 2 and 3 (81.8%; 9/11) were numerically higher than of Group 1 (63.6%; 7/11), the difference among the groups was statistically insignificant. The multiple birth rate of Group 3 was found higher than Groups 1 and 2. However, the number of single lambs of Group 1 was also higher than Groups 2 and 3 (p < 0.05). Despite the litter sizes of Groups 2 (1.27; 14/11) and 3 (1.55; 17/11) being numerically higher than Group 1 (0.73; 8/11), the differences among all the groups were statistically insignificant. In conclusion, the administration of PGF(2alpha) at the time of removal of the sponge shortens the injection oestrus-onset and oestrus-end interval in Awassi ewes treated with progestagen-PMSG. Additionally, exogenous GnRH treatment immediately after the AI increases the multiple birth rate of Awassi ewes synchronized with progestagen-PMSG-PGF(2alpha) combination.


Reproduction in Domestic Animals | 2011

Effect of pregnancy and foetal number on diameter of corpus luteum, maternal progesterone concentration and oxidant/antioxidant balance in ewes

Seyfettin Gür; Gaffari Türk; E Demirci; Abdurrauf Yüce; Mustafa Sönmez; Ş Özer; Emrah Hicazi Aksu

The aim of this study was to determine the changes in diameter of corpus luteum (CL), maternal progesterone (P) concentration, lipid peroxidation and non-enzymatic antioxidant levels along with enzymatic antioxidant activities in pregnant ewes bearing single and twin foetuses. The ewes were selected from healthy animals that were brought to the abattoir for slaughtering. The ewes were divided into three groups: Group 1 (non-pregnant, non-oestrous, n = 30), Group 2 (pregnant bearing a single foetus, n = 30) and Group 3 (pregnant bearing twin foetuses, n = 12) after they were slaughtered. Pregnant ewes were in the first half of the pregnancy. The diameter of CL and P concentration of pregnant ewes bearing a single foetus or twin foetuses were found higher than that found in non-pregnant ewes. Similarly, the P concentration of pregnant ewes bearing twin foetuses was higher than that found in pregnant ewes bearing a single foetus. Malondialdehyde (MDA) level in pregnant ewes bearing twin foetuses was higher than that found in both non-pregnant and pregnant ewes bearing a single foetus. The serum glutathione (GSH) level and glutathione-peroxidase (GSH-Px) activity of pregnant ewes bearing twin foetuses were found lower than that found in non-pregnant ewes. Additionally, the GSH-Px activity of pregnant ewes bearing twin foetuses was found lower than that found in pregnant ewes bearing a single foetus. No significant difference was found between pregnant ewes bearing female and male foetus with respect to diameter of CL, P concentration and oxidative stress parameters. There were significant positive correlations between foetal number (0, 1, 2) and diameter of CL, P concentration, MDA level, and between P concentration and diameter of CL, MDA level. However, significant negative correlations were found between foetal number (0, 1, 2) and GSH level, GSH-Px activity, and between P concentration and GSH-Px activity. In conclusion, the diameter of CL enlarges, P production increases and oxidant/antioxidant balance impairs because of the gestation stress in ewes during pregnancy.


Animal Reproduction Science | 2009

The effect of vitamin E treatment during preovulatory period on reproductive performance of goats following estrous synchronization using intravaginal sponges

Mustafa Sönmez; Tanzer Bozkurt; Gaffari Türk; Seyfettin Gür; Meltem Kızıl; Abdurrauf Yüce

The objectives of this study were to investigate whether the use of intravaginal sponge for estrous synchronization of goats causes oxidative stress, and to examine the effect of administering vitamin E during preovulatory period on reproductive performance of estrous synchronized goats. Estrus was synchronized in 36 non-lactating adult does using intravaginal sponges containing 30 mg of fluorogestane acetate (FGA) for 14 days. All females received 500 IU of eCG at the sponge withdrawal. The goats were allocated at random to two groups balanced for breed, age and body weight. Treatment group (n=18) received 200mg of vitamin E i.m. at the time of sponge removal and again at the time of second artificial insemination. The other 18 goats (control) were administered 1 ml of physiological saline instead of vitamin E on each of these two occasions. All does in estrus was intracervically inseminated at 12 and 24h after the onset of estrus. Blood samples were collected every 72h during the experimental period for evaluation of malondialdehyde (MDA) and vitamin E concentrations. Serum MDA level increased and vitamin E concentration decreased during the period of vaginal sponge application. Following the sponge removal, MDA level declined rapidly to below basal level in the treatment group but remained high in the control group. Conversely, vitamin E concentration increased in the treatment group after the sponge withdrawal and remained at a low level in the control group. No statistically significant differences (P>0.05) were observed between groups in terms of estrous response, conception rate, gestation length or kidding rate. However, the number of multiple births (70.0% versus 50.0%) and prolificacy rate (2.40+/-0.37 versus 1.63+/-0.26 kids per kidding) were significantly higher (P<0.05) for the treatment group than those of the control group. The results indicate that the use of intravaginal sponges for estrous synchronization of goats causes an increase in level of oxidative stress. However, the vitamin E treatment during preovulatory period can prevent the overproduction of reactive oxygen species (ROS), and it may improve the multiple birth rates and the number of kids born in estrous synchronized goats.


Animal Biology | 2012

An investigation on the sperm number and reproductive parameters of males in wild caught freshwater crayfish (Astacus leptodactylus, Eschscholtz)

Muzaffer Mustafa Harlıoğlu; Filiz Kutluyer; Seyfettin Gür

In the present study, the sperm number of wild caught Astacus leptodactylus was counted in the beginning of reproduction season. In addition, the reproductive system, testes, and vasa deferentia were weighed, and gonado-somatic index and testicular index were calculated. Twenty-five adult males of A. leptodactylus were used for the study. Significant linear regressions were found between body length (and weight) and sperm count, reproductive system weight, testes weight and vasa deferentia weight ( P < 0 . 05 ). The mean sperm number of vas deferens for the size range of 41-56 mm carapace length crayfish was 5.72 ± 4.54 × 109 sperm/distal vas deferens (DVD) section. Sperm number ranged from 4 × 108 to 8.5 × 109 sperm/DVD section. The results revealed that an increase in body weight causes an increase in sperm number. For example, mean sperm number was 3.87 ± 2.87 × 109 for the weight range of 15-24 g crayfish, 5.01 ± 2.62 × 109 for the weight range of 25-35 g crayfish and 7.37 ± 2.87 × 109 for the weight range of 36-42 g crayfish. In conclusion, this study provides some data on the male reproduction characters and needs to be improved with details about the reproductive performance of males (i.e., sperm number and quality) in order to reach a maximum reproductive efficiency in captivity.


Andrologia | 2012

Relationships between seminal plasma arginase activity and spermatological parameters in rams

Seyfettin Gür; Fatih Mehmet Kandemir

This study was conducted to evaluate the correlation between seminal plasma arginase activity and spermatological parameters in rams. In this study, five fertility‐proven Awassi rams were used as material. Six ejaculates were collected from each ram by an artificial vagina. Spermatological parameters (semen volume, mass activity, sperm motility and concentration and abnormal sperm rate) were immediately determined in each ejaculate. For enzyme assay, the semen samples were centrifuged and stored at −20 °C for the analysis of arginase activity. The average seminal plasma arginase activity was 0.61 ± 0.20 U (mg protein)−1. There was a positive correlation between arginase activity and semen volume (r = 0.412, P < 0.05), semen mass activity (r = 0.610, P < 0.01), sperm motility (r = 0.447, P < 0.05) and sperm concentration (r = 0.808, P < 0.01). However, there was a negative correlation between arginase activity and abnormal sperm rate (r = −0.424, P < 0.05). In conclusion, this study clearly suggests that there is a significant correlation between seminal plasma arginase activity and spermatological parameters. In light of these results, seminal plasma arginase activity may be a biochemical criterion for determining sperm quality besides classical semen analysis parameters in rams.


Animal Reproduction Science | 2018

Optimization of the incubation time and temperature for spermatozoa extraction in freshwater crayfish Pontastacus leptodactylus (Eschscholtz, 1823)

Ardavan Farhadi; Muzaffer Mustafa Harlıoğlu; Seyfettin Gür; Tutku Can Acısu

Determination and control of spermatozoa quality in crustacean aquaculture is an important issue for successful and controlled reproduction. Investigation of spermatozoa number in spermatophores is a basic and common parameter for determining the reproductive quality in farmed decapods. In the present study, spermatozoa extraction from spermatophores located in the ductus deferens was conducted in Pontastacus leptodactylus using different incubation times and temperatures. The results indicate that the duration of incubation and temperature affected (P < 0.05) spermatozoa extraction. Greater temperatures (40 and 75 °C) resulted in a reduction (P < 0.05) in number of extracted spermatozoa. In contrast, more spermatozoa were extracted when the 4 and 23 °C temperatures were imposed. After 4 h of incubation, the number of extracted spermatozoa were greatest in number at 23 °C. In conclusion, the greater numbers of crayfish spermatozoa can be obtained when the ductus deferens containing spermatophores is incubated at 23 °C for 4 h as compared with other temperatures and incubation durations. The results of present study are useful for assessing spermatozoa quality in aquaculture as well as the extraction of spermatozoa for research purposes.


Reproductive Toxicology | 2006

Protective role of lycopene on cisplatin-induced changes in sperm characteristics, testicular damage and oxidative stress in rats

Ahmet Ateşşahin; Izzet Karahan; Gaffari Türk; Seyfettin Gür; Seval Yilmaz; Ali Osman Çeribaşı

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