Browsing by Author "Keleştimur, Haluk"

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Citation Count: 0
Asprosin-induced alterations in female rat puberty and reproductive hormonal profiles
(Taylor & Francis Ltd, 2024) Kacar, Emine; Oz, Zeynep Dila; Serhatlioglu, Ihsan; Tektemur, Nalan Kaya; Ozdede, Mehmet Ridvan; Yalcin, Tugce; Kelestimur, Haluk; Fizyoloji / Physiology
ObjectiveTo investigate the comprehensive effects of daily chronic asprosin administration on various pubertal and reproductive parameters in female rats. This study aims to elucidate the role of asprosin in regulating the onset of puberty and its influence on hormonal profiles and ovarian histology.MethodsAsprosin was administered intraperitoneally (i.p.) at a dose of 500 ng/kg daily for eight weeks. Hormonal assays and histological analyses were performed to evaluate the effects of asprosin on the onset of puberty and reproductive function.ResultsDaily chronic administration of asprosin accelerated the onset of the first oestrus. Hormonal assays revealed significant elevations in serum levels of Follicle-Stimulating Hormone (FSH) and Oestradiol (E2), while Inhibin B levels decreased. Histological evaluations demonstrated an increased number of primary and secondary follicles in ovarian tissue, without affecting primordial follicle counts or reproductive organ weights.ConclusionsRole of adipokines in regulating puberty and reproductive function has increasingly gained recognition. This study aimed to provide the first comprehensive examination of the effects of daily chronic asprosin administration on pubertal and reproductive parameters in female rats. Utilising hormonal assays and histological analyses, asprosin was administered intraperitoneally (i.p.) at a dose of 500 ng/kg, daily, for eight weeks. Our findings revealed that daily chronic administration of asprosin accelerated the onset of the first oestrus. Hormonal assays showed significant elevations in serum levels of Follicle-Stimulating Hormone (FSH) and Oestradiol (E2), while Inhibin B levels decreased. Histological evaluations demonstrated an increased number of primary and secondary follicles in ovarian tissue, without affecting primordial follicle counts or reproductive organ weights. These results provide new insights into asprosin's role in advancing the age of first oestrus and modulating hormonal profiles, thereby offering potential benefits to the female reproductive system.
Citation Count: 0
Effect of External Innovation Capacity on Company Level Innovativeness
(Management & Business Acad, 2021) Okatan, Kagan; Alankus, Orhan Behic; Fizyoloji / Physiology
This study focuses on the correlation of national innovation inputs and the external innovation environment with the company-level innovation output. Since all companies are aiming at sustainable innovation to ensure sustainable profit growth, the current literature has highlighted the need for a well-structured internal innovation system for innovation success and discussed the factors affecting the performance of organisations. The internal innovation system has its own dimensions that affect the success of the whole system and emphasize the significant impact of firms on innovation results. Do all companies with a high internal innovation competency and a suitable corporate culture have the chance to become worldwide innovative? What are the impacts of the external environment where the companies are located on the innovation success? And how big is the importance of external environmental inputs? This study seeks to answer these questions and draws attention to the appropriate external environment and conditions to increase firms' innovation competencies.
Citation Count: 0
The Effects of Chronic Asprosin Administration on Monoamine Levels in the Arcuate Nucleus, Ventromedial Hypothalamus and Dorsomedial Hypothalamus Regions
(Wiley, 2023) Ozdede, Mehmet Ridvan; Kacar, Emine; Oz, Zeynep Dila; Ozgen, Aslisah; Serhatlioglu, Ihsan; Yilmaz, Bayram; Kelestimur, Haluk; Fizyoloji / Physiology
[No Abstract Available]
Citation Count: 0
The Effects of Chronic Asprosin Administration on Sense of Smell and Sexual Behavior in Female Rats
(Karger, 2023) Oz, Zeynep Dila; Kacar, Emine; Serhatlioglu, Ihsan; Ozdede, Mehmet Ridvan; Atila, Busra; Horoz, Mert Ali; Kelestimur, Haluk; Fizyoloji / Physiology; Fizyoloji / Physiology
IntroductionAsprosin is an adipokine released from white adipose tissue during fasting and acts through the olfactory receptor. It is known that adipokines play roles in reproductive physiology in mammals. However, there are very few studies conducted on role of asprosin in reproductive functions. There are no studies on its relationship with sexual motivation. It was shown in the literature that administration of asprosin to male mice improves olfaction. It is also known that there is a strong correlation between smell and sexual desire. In view of this, it was hypothesized that chronic administration of asprosin would improve olfactory performance and increase sexual incentive motivation in female rats for male partners. MethodsThis hypothesis was tested by applying the hidden cookie test, sexual incentive test, active research test, and sexual behavior test. The changes in serum hormone levels in female rats that chronically received asprosin were also measured and compared. ResultsChronic asprosin exposure increased olfactory performance, male preference ratio, male investigation preference ratio, activity index, and anogenital investigation behavior. Also, serum oxytocin and estradiol levels increased following chronic administration of asprosin in female rats.Discussion/ConclusionThese data suggest that chronic administration of asprosin can result in increased sexual incentive motivation for opposite-sex in female rats over increased olfactory performance and changes in reproductive hormones.
Citation Count: 1
Effects of Irisin on the Reproductive System of Obese Female Rats Induced by a High-fat Diet
(Univ Ljubljana, 2024) Ertugrul, Nazife Ulker; Yardimci, Ahmet; Tektemur, Nalan Kaya; Bulut, Ferah; Ozcan, Mete; Kelestimur, Haluk; Canpolat, Sinan; Fizyoloji / Physiology
Obesity is becoming more common all across the world, causing a variety of health problems, including reproductive disruption. Although the novel, exercise -induced hormone irisin may affect the hypothalamus -pituitary -gonadal axis and reproductive function control, its impact on obesity -induced damage to the female reproductive system is not fully known. Hence, this study aimed to investigate the potential effects of irisin on reproductive hormones and reproductive organs in female rats with obesity induced by a high -fat diet. Forty female rats were divided into four groups: control, irisin, obese, and obese+irisin (n = 10 in each group). After simulating a high -fat diet -induced obesity model (via 60% kcal fat for 12 weeks) in the obese and obese+irisin groups, irisin (100 ng/kg/day via mini -osmotic pumps for about 28 days) was administered subcutaneously to the irisin and obese+irisin groups. Results showed that subcutaneous irisin perfusion increased serum luteinizing hormone (LH), the LH to follicle -stimulating hormone (FSH) ratio (LH/FSH), and progesterone levels while decreasing the histopathological damage in the ovaries of obese rats. On the other hand, endogenous irisin serum concentrations were similar in lean female rats and obese female rats with reproductive disorders. These results suggest that irisin may affect the reproductive axis in obese female rats. An increase in serum LH levels, which trigger ovarian steroidogenesis, and reducing histopathological changes in ovarian tissue could contribute to this effect.
Citation Count: 0
Investigation of the Efficacy of Asprosin Given with Brain Infusion Kit on Reproductive Organs and Testosterone Hormone in Male Rats
(Wiley, 2023) Kacar, Emine; Tan, Fatih; Ozdede, Mehmet Ridvan; Oz, Zeynep Dila; Serhatlioglu, Ihsan; Yilmaz, Bayram; Kelestimur, Haluk; Fizyoloji / Physiology
[No Abstract Available]
Citation Count: 0
Modulation of Melatonin Receptors Regulates Reproductive Physiology: The Impact of Agomelatine on the Estrus Cycle, Gestation, Offspring, and Uterine Contractions in Rats
(Acad Sciences Czech Republic, inst Physiology, 2023) Kacar, Emine; Tan, Fatih; Sahinturk, Serdar; Zorlu, Gokhan; Serhatlioglu, Ihsan; Bulmus, Ozgur; Kelestimur, Haluk; Fizyoloji / Physiology; Fizyoloji / Physiology
Agomelatine is a pharmaceutical compound that functions as an agonist for melatonin receptors, with a particular affinity for the MT1 and MT2 receptor subtypes. Its mode of action is integral to the regulation of diverse physiological processes, encompassing the orchestration of circadian rhythms, sleep-wake cycles, and mood modulation. In the present study, we delve into the intricate interplay between agomelatine and the modulation of estrus cycles, gestation periods, offspring numbers, and uterine contractions, shedding light on their collective impact on reproductive physiology. Both in vivo and in vitro experiments were performed. Wistar Albino rats, divided into four groups: two non-pregnant groups (D1 and D2) and two pregnant groups (G1 and G2). The D1 and G1 groups served as control groups, while the D2 and G2 groups received chronic agomelatine administration (10 mg/kg). Uterine contractions were assessed in vitro using myometrial strips. Luzindole, a melatonin receptor antagonist, was employed to investigate the pathway mediating agomelatine's effects on uterine contractions. In in vivo studies, chronic agomelatine administration extended the diestrus phase (p<0.05) in non-pregnant rats, prolonged the gestational period (p<0.01), and increased the fetal count (p<0.01) in pregnant rats. Additionally, agomelatine reduced plasma oxytocin and prostoglandin-E levels (p<0.01) during pregnancy. In vitro experiments showed that agomelatine dose-dependently inhibited spontaneous and oxytocin-induced myometrial contractions. Luzindole (2 mu M) reverse the agomelatine-induced inhibition of myometrial contractions. These findings suggest that agomelatine holds the potential to modulate diverse reproductive parameters during the gestational period, influencing estrus cycling, gestational progression, offspring development, and the orchestration of uterine contractions.
Citation Count: 0
Selektif Serotonin Geri-Alım İnhibitörü (SSRI) Paroksetin ve Norepinefrin-Dopamin Geri-Alım İnhibitörü Bupropiyonun Cinsel İşlev Üzerine Etkilerinde Arg-Phe-Amide (RFamide)-Related Peptidlerin Karşılaştırmalı Rolleri Üzerine İn Vivo ve İn Vitro Çalışmalar
(2016) Keleştimur, Haluk; Yılmaz, Bayram; Atmaca, Murad; Özcan, Mete; Canpolat, Sinan; Bulmuş, Özgür; Yardımcı, Ahmet; Fizyoloji / Physiology
Cinsel işlev bozuklukları antidepresanların en sık görülen yan etkilerinden olmalarına karşılık etki mekanizması henüz iyi bilinmemektedir. Antidepresanların bu yan etkilerine ilişkin nöroendokrin mekanizmanın ortaya çıkarılması için Sprague-Dawley türü erkek sıçanlarda paroksetin, bupropion ve agomelatinin etkileri araştırıldı. Paroksetin verilen hayvanların hipotalamusunda kisspeptin ve RFRP-3 ekspresyonları sırasıyla azalma ve artış gösterdi. Antidepresanların tümü sperm üretiminde azalmaya yol açtılar. Çalışmanın sonuçları, paroksetinin sebep olduğu cinsel işlev bozukluğunun RFRP-3 ekspresyonundaki artıştan ileri gelebileceğini ve ayrıca sperm üretimindeki azalmanın kisspeptin ekspresyonundaki değişiklikler ile ilgili olabileceğini göstermektedir. Agomelatin, cinsel işlevde bir bozukluğa yol açmadan antidepresan etkiye sahip oldu. Kisspeptinin antidepresan etkileri ile adrenerjik ve serotonerjik reseptörlerin rolü zorlu yüzme testi kullanılarak araştırıldı. Kisspeptin immobiliteyi azalttı ve bu sebeple antidepresan etkiye sahip olduğu sonucuna varıldı. Kisspeptinin antidepresan etkilerinin GPR54 reseptörlerinin yanı sıra kısmen de olsa alfa2-adrenerjik ve 5-HT2 serotonerjik reseptör ile ilişkili olabileceği sonucuna varıldı. Proje kapsamında ilk defa kisspeptinin antidepresan etkisinin kisspeptin antagonisti p234 tarafından önlendiği belirlenmiştir. Böylece kisspeptinin antidepresan etkisini göstermesinde kisspeptin reseptörünün rolü belirgin bir şekilde ortaya konulmuştur. GPR54 reseptörünün hipokampusun dentate gyrus hücrelerinde yüksek düzeyde eksprese edilmesi sebebiyle, kisspeptinin etkisini hipokampustaki reseptörü aracılığıyla göstermesi ihtimal dahilindedir. Proje kapsamında kisspeptinin sadece üreme faaliyetlerinin hipotalamus düzeyinde kontrolünden sorumlu olmayıp enerji dengesi yönünden de önemli etkilere sahip olabileceği ve yakın gelecekte kilo artışını yavaşlatacak farmakolojik etkilerinden yararlanabileceği sonucuna varıldı. Çalışmanın in vitro kısmında, nörotransmitterlerin kisspeptin ve RFRP-3 nöronları üzerindeki etkileri gözlendi. Arg-Phe-amide-related peptidlerin üreme aksı üzerindeki etkilerini ortaya çıkarmak amacıyla kisspeptin ve RFRP-3 eksprese eden rHypoE-7 ve rHypoE-8 hücre hatları kullanıldı. Nörotransmitterlerin hiçbiri hücre içi kalsiyum konsantrasyonunda önemli bir değişikliğe yol açmadı. Sadece serotonin rHypoE-7 hücrelerinde kisspeptin salgılanmasını artırdı. Bundan dolayı, serotoninin üreme aksı üzerindeki etkisini kisspeptin sekresyonunda değişiklik oluştuırmak suretiyle göstermesi muhtemel görünmektedir.
Citation Count: 0
Treadmill exercise has healing effects on obesity-induced sexual behavior disorder through kisspeptin and kiss1R expression in male rats
(C M B Assoc, 2023) Kacar, Emine; Bulmus, Ozgur; Ercan, Zubeyde; Kavuran, Ilay Buran; Zorlu, Gokhan; Tan, Fatih; Kelestimur, Haluk; Fizyoloji / Physiology; Fizyoloji / Physiology
The basic objective of this study was to examine the possible effects of treadmill exercise on obesity-related sexual behavior disorder in obese male rats and the role of kisspeptin in this effect. The rats were separated from their mothers at the age of 3 weeks, and classified into four groups as Control (C): normal diet-sedentary group, Exercise (E): normal diet-exercise group, Obese (O): high-fat diet-sedentary group, Obese + Exercise (O+E): high-fat diet-exercise grouSexual behavioral testing was conducted in the rats. At the end of the study, brain samples were taken from the animals for gene expression analyses. The treadmill exercise caused a significant increase in the O+E Group compared to the O Group in kisspeptin and kiss1R gene expression and in EF, ML, IL, MF, IF, III, EL, PEI, IR1, MFT, IFT, IRT sexual behavior parameters (p<0.05), and a significant decrease in ML, IL, III, EL sexual behavior parameters (p<0.05). Treadmill exercise caused a significant decrease in EF, ML, IL, MF, IF, III, EL, PEI, IR1, MFT, IFT, IRT sexual behavior parameters and kisspeptin and kiss1R gene expression in the hypothalamus, hippocampus, prefrontal cortex and corpus striatum in E Group compared to C Group (p<0.05), and a significant increase in ML, IL, III, EL sexual behavior parameters (p<0.05). Based on this effect, we believe that it is caused by an increase in kisspeptin and kiss1R expression in the hypothalamus, hippocampus, prefrontal cortex and corpus striatum. In conclusion, treadmill exerciseinduced kisspeptin secretion may increase GnRH secretion and cause hypothalamo-pituitary gonadal axis activation and ameliorative effect on deteriorated sexual function.
Citation Count: 0
Treadmill Exercise Improves Behavioral and Neurobiological Alterations in Restraint-Stressed Rats
(Springernature, 2023) Ercan, Zubeyde; Bulmus, Ozgur; Kacar, Emine; Serhatlioglu, Ihsan; Zorlu, Gokhan; Kelestimur, Haluk; Fizyoloji / Physiology; Fizyoloji / Physiology
Stress is a state that is known to impact an organism's physiological and psychological balance as well as the morphology and functionality of certain brain areas. In the present work, chronic restraint stress (CRS) model rats treated with treadmill exercise were used to examine anomalies associated to emotion and mood as well as molecular changes in the brain. Forty male Sprague-Dawley rats were divided into control, stress, exercise, and stress+exercise groups. CRS were exposed to stress group rats and exercise group underwent a chronic treadmill exercise. Depressive-like behavior was evaluated with the forced swim test (FST) and tail suspension test (TST). For assessing anxiety-like behavior, the light-dark test (LDT) and the open field test (OFT) were used. The Morris water maze test (MWMT) was used for testing memory and learning. Brain's monoamine level and the expression of genes related to stress were measured. It was discovered that CRS lengthens latency in the MWMT, increases immobility in the FST and TST, decreases time in the light compartment, and causes hypoactivity in the OFT. CRS reduced the dopamine levels in the nucleus accumbens(NAc). Brain-derived neurotrophic factor (BDNF), dopamine receptors, and serotonin receptor (HTR2A) gene expression in the prefrontal cortex, corpus striatum, and hypothalamus were decreased by CRS. Exercise on a treadmill leads to increase NAc's dopamine and noradrenaline levels and prevented behavioral alterations. Exercise increased the alterations of BDNF expressions in the brain in addition to improving behavior. As a result, CRS-induced behavioral impairments were effectively reversed by chronic treadmill exercise with molecular alterations in the brain.
Citation Count: 1
Treadmill exercise training improves the high-fat diet-induced behavioral changes in the male rats
(Springer Heidelberg, 2022) Bulmus, Ozgur; Ercan, Zubeyde; Kacar, Emine; Serhatlioglu, Ihsan; Yasar, Abdullah; Kelestimur, Haluk; Fizyoloji / Physiology; Fizyoloji / Physiology
The purpose of this study was to investigate the effects of treadmill exercise training on obesity-induced behavioral changes in high-fat diet (HFD)-induced male rats. In this study, 40 male Sprague-Dawley rats were divided into 4 groups after they were weaned: Control (C), Exercise (E), Obese (O) and Obese + Exercise (O + E). For the obesity model % 60 high-fat diet were applied. After obesity was induced, rats were either moderate aerobic exercise (treadmill running) trained or left untrained. Different tasks to assess spatial learning and memory (Morris water maze test (MWMT)), depressive-like behavior (forced swimming test(FST), tail suspension test (TST) and anxiety-like behavior (light-dark test (LDT) and open field test (OFT)) were conducted. Exercise caused a significant reduction in duration of immobility in the O group in FST and the decrease in immobility in the O + E rats in TST. The O + E rats demonstrated a significant increase in the time spent in the light box as compared to the O group in the LDT. The O + E rats did not show any behavioral alterations as compared to all the other groups in the OFT. In the O + E group, there was a significant increase in the time spent in the target quadrant compared to the O group in the MWMT. Our results support that treadmill exercise could improve cognitive, depressive-like, anxiety-like behavioral changes in the HFD-induced obese rats.
Citation Count: 0
TRPM2 may be involved in high fructose corn syrup-induced anxiety-like behavior in adult male rats
(C M B Assoc, 2023) Serhatlioglu, Ihsan; Zorlu, Gokhan; Yardimci, Ahmet; Ertugrul, Nazife Ulker; Ercan, Zubeyde; Tan, Fatih; Kelestimur, Haluk; Fizyoloji / Physiology; Fizyoloji / Physiology
Excessive high fructose corn syrup (HFCS) consumption is known to cause oxidative stress, which induces transient receptor potential melastatin type 2 (TRPM2) channel gating. Oxidative stress-induced TRPM2 gating is suggested to play an important role in neurons, indicating a role for the TRPM2 channel in a variety of neuropsychiatric disorders including depression and anxiety. We investigated the effects of HFCS and chronic immobilization stress (CIS) on TRPM2 channel immunoreactivity, anxiety, and depressive-like behaviors in adult male rats. The male rats (n=8/group) were divided into 4 groups: Control, 20% HFCS (F20), 40% HFCS (F40), and stress. The control group received tap water, and F20 and F40 groups were exposed to 20% and 40% HFCS respectively for 14 consecutive days. Rats in the stress group were subjected to immobilization stress for 3 or 6 hours daily in the first and second weeks to induce CIS. Then, light/dark test, open field test (OFT), and tail suspension test (TST) were performed, respectively. In the light/dark test, the time spent in the dark chamber significantly increased in all groups vs the control group (P<0.01). In support of this result, the time spent in the light chamber significantly decreased in all groups vs the control group (P<0.01). Besides, CIS significantly increased depressive-like behavior in the stress group vs the control group (P<0.05). In serum hormone levels, corticosterone (CORT) levels significantly increased in the F40 and stress groups vs the control group (P<0.01). TRPM2 immunoreactivity significantly increased in the hippocampus, prefrontal cortex (PFC), nucleus accumbens (NaC), and amygdala regions by HFCS and CIS treatments. For the first time the present study showed that increased immunoreactivity of the TRPM2 cation channels may be linked to the anxiety-like behavior induced by HFCS.