Browsing by Author "Altunkaynak, Berrin Zühal"

Now showing 1 - 20 of 26

Citation Count: 1
Applications of various stereological tools for estimation of biological tissues
(Wiley, 2023) Warille, Aymen A.; Kocaman, Adem; Elamin, Abdalla A.; Mohamed, Hamza; El Elhaj, Abubaker; Altunkaynak, Berrin Zuhal; Histoloji ve Embriyoloji / Histology and Embriology
To provide concise and brief important stereological application methods and techniques for estimating biological tissues. Stereology studies the quantity of biological tissue using little practice and the low price of counting and preparing tissue slices to obtain direct and accurate results. Since their establishment, the stereological techniques underwent much improvement, thus allowing more precise analysis of target structures using various approaches. Using stereological tools, advances in stereological techniques made the target tissues or organs represented by 2D instead of 3D dimensions. Process tools estimate volume, area and length. According to the exciting tissue and aims, the stereological tools perform differently. This review summarizes various stereological tools and techniques, providing brief information about the orientation method, slicer probe method, Delesse's principle, Cavalieri principle, disector, fractionator, nucleator, virtual cycloids and saucer, which are described in detail.
Citation Count: 14
Biochemical, immunohistochemical and morphometrical investigation of the effect of thymoquinone on the rat testis following exposure to a 900-MHz electromagnetic field
(Elsevier Gmbh, 2020) Yahyazadeh, Ahmad; Altunkaynak, Berrin Zuhal; Kaplan, Suleyman; Histoloji ve Embriyoloji / Histology and Embriology
Long-term use of cell phones emitting electromagnetic fields (EMFs) have raised concerns regarding public health in recent year. We aimed to investigate the possible effects of 900 MHz EMF exposure (60 min/day for 28 days) on the rat testis. Another objective was to determine whether the deleterious effect of EMF radiation would be reduced by the administration of thymoquinone (TQ) (10 mg/kg/day). Twenty-four male adult Wistar albino rats were randomly selected, then assigned into four groups as followControl, EMF, TQ and EMF + TQ. Testicular samples were analyzed using histological, stereological, biochemical and immunohistochemical techniques. Total numbers of primary spermatocytes and spermatids as well as Leydig cells were significantly decreased in the EMF group compared to the Control group (p < 0.05). In the EMF + TQ group, the total number of primary spermatocytes was significantly increased compared to the EMF group (p < 0.05). Superoxide dismutase (SOD) activity was significantly increased in the EMF group compared to the Control group (p< 0.05). Also, serum testosterone levels and wet weight of testes were significantly decreased in the EMF group compared to the Control group (p < 0.05). Our findings suggested that exposure to a 900 MHz EMF had adverse effects on rat testicular tissue and that the administration of TQ partially mitigated testicular oxidative damages caused by EMF radiation.
Citation Count: 5
Effect of Luteolin on Biochemical, Immunohistochemical, and Morphometrical Changes in Rat Spinal Cord following Exposure to a 900 MHz Electromagnetic Field
(Chinese Center Disease Control & Prevention, 2020) Yahyazadeh, Ahmad; Altunkaynak, Berrin Zuhal; Histoloji ve Embriyoloji / Histology and Embriology
Objective This study aimed to investigate the effect of exposure to a 900 MHz electromagnetic field (EMF) on the cervical spinal cord (CSC) of rats and the possible protective effect of luteolin (LUT) against CSC tissue damage. Methods Quantitative data were obtained via stereological, biochemical, immunohistochemical, and histopathological techniques. We investigated morphometric value, superoxide dismutase (SOD) level, and the expression of high-mobility group box 1 protein molecules, as well as histological changes. Results The total number of motor neurons in the EMF group significantly decreased in comparison with that in the control group (P < 0.05). In the EMF + LUT group, we found a significant increase in the total number of motor neurons compared with that in the EMF group (P < 0.05). SOD enzyme activity in the EMF group significantly increased in comparison with that in the control group (P < 0.05). By contrast, the EMF+LUT group exhibited a decrease in SOD level compared with the EMF group (P < 0.05). Conclusion Our results suggested that exposure to EMF could be deleterious to CSC tissues. Furthermore, the protective efficacy of LUT against SC damage might have resulted from the alleviation of oxidative stress caused by EMF.
Citation Count: 0
The effects of bortezomib on the ovariectomy applied rat uterus: A histopathological, stereological, and immunohistochemical study
(Mashhad Univ Med Sciences, 2018) Khoshvaghti, Habib; Altunkaynak, Berrin Zuhal; Histoloji ve Embriyoloji / Histology and Embriology
Objective(s): In this study, potential protective effects of Bortezomib (Bort), as a proteasome inhibitor, were investigated on the uterus of ovariectomized rats by histological, morphometric and immunohistochemical methods. Materials and Methods: In this study, 18 Sprague dawley strain female rats (12 weeks old, 250-300 g body weight) were used. Animals in the control group (Cont, n=6) were not exposed to any treatment. Ovariectomy was performed on the experimental groups. They (n=12) were divided into ovariectomy (Ovt, n=6) and Bortezomib (Bort, n=6) subgroups. Twelve weeks later, the rats were perfused. Then, uterine tissues were removed and examined by morphometrical, and light and electron microscopy methods. In addition, immunoreactivity of nuclear factor-kappa (NF-kappa B) was evaluated. Results: Morphometric and histopathological evaluations showed that Bort was effective in the uterus and protects the layer structures and the cells. Conclusion: In the light of these findings, we suggest that for proteasome inhibitor particularly Bort is thought to be useful through proteasome inhibition and NF-kappa B pathway.
Citation Count: 1
The effects of different doses of diclofenac sodium on newborn rat hippocampus exposed during the third trimester
(Tubitak Scientific & Technological Research Council Turkey, 2020) Elibol, Ebru; Kaplan, Suleyman; Altun, Gamze; Aksoy, Abdurrahman; Altunkaynak, Berrin Zuhal; Histoloji ve Embriyoloji / Histology and Embriology
The main aim of the present study was to examine the neurotoxic effects of prenatal exposure to varying doses of diclofenac sodium (DS) on the rat hippocampus. Twenty-eight Wistar albino adult female rats weighing 280-300 g were initially used for pregnancy. When vaginal plaques were seen in female rats, it was accepted as the 0th day of pregnancy. Female rats were divided into five main groups; pure control, saline, low dose DS (3.6 mg/kg), moderate dose DS (9 mg/kg), and high dose DS (18 mg/kg). They were exposed to these treatments during their gestation. After birth, all newborn male rats were euthanized by overdose anesthesia on the 7th postnatal day. Histological and stereological techniques were used for analyzing tissue samples. The stereological analyses in this study showed that the number of neurons in the hippocampus may be reduced due to the use of DS. Histological investigation of the drug-treated groups showed significant cell loss compared to the control. Darkly stained nuclei of the neurons in the high dose group compared to the other groups were also obvious. When the results are evaluated, it can be concluded that the use of diclofenac sodium during pregnancy may have teratogenic effects on the development of the nervous system.
Citation Count: 0
The effects of myricitrin and chebulinic acid on the rat hippocampus exposed to gamma radiation: A stereological, histochemical and biochemical study
(Elsevier, 2023) Uzun, Sumeyye Gumus; Altunkaynak, Berrin Zuhal; Alkan, Isinsu; Histoloji ve Embriyoloji / Histology and Embriology
Aim: Gamma radiation, a form of ionizing radiation, is used in many different areas, especially in the health field and in the treatment of cancer. However, gamma radiation used for therapeutic purposes also has numerous harmful effects on human health. This study was planned to investigate the impacts of exposure to gamma ra-diation on the hippocampal area and the preventive effects of myricitrin and chebulinic acid against that damage.Material and method: Thirty-six male Wistar albino rats were randomly divided into six groups. The control group was exposed to no treatment. The chebulinic acid and myricitrin groups were injected with the relevant drug at a dosage of 0.033 mg/kg) (vehicle; normal saline) per day. The gamma groups were placed in a plexiglass test setup with their heads positioned close to the source. The subjects were exposed to radiation with a mixed source containing radioactive Cs-137 and Co-60 isotopes obtained from Ondokuz Mayis University Physics Department Nuclear Physics Laboratory for 1 h. Gamma radiation was applied 16 mGy for one hour per day for 10 days. The gamma radiation+chebulinic acid and the gamma radiation myricitrin groups also received 0.033 mg/kg per day of these drugs via injection. Immediately after the experimental procedure, all animals were subjected to behavioural tests, and perfused brain tissues were analyzed using stereological methods.Results: Stereological analysis showed that gamma radiation caused a decrease in the numbers of neurons in the hippocampal area (p < 0.01; One-way ANOVA) and that chebulinic acid and myricitrin reduced this decrease (p < 0.01; One-way ANOVA). Decreases in learning and memory capacity were detected in behavioural tests in rats from the Gamma group.Conclusion: The study findings showed that that the adverse health effects of Gamma radiation can be amelio-rated using myricitrin and chebulinic acid. Myricitrin was more effective in terms of cell proliferation and defence against oxidative stress than chebulinic acid, and exhibited a more neuroprotective effect. However, more detailed analyses should be performed before using either antioxidant for therapeutic purposes.
Citation Count: 2
Effects of tacrolimus on c-fos in hippocampus and memory performances in streptozotocin model of Alzheimer's disease of rats
(Tubitak Scientific & Technological Research Council Turkey, 2021) Koylu, Ayse; Altunkaynak, Berrin Zuhal; DelIbas, Burcu; Histoloji ve Embriyoloji / Histology and Embriology
Background/aim: Calcineurin, an inhibitor of calcium dependent phosphatase is highly presented in a brain of an Alzheimer's disease. Aging brain gets more sensitive to hyperactivation of calcineurin, and this event causes tau neurofibrillary plaque accumulation, which is one of the outcomes of this disease. The regions of hippocampus are much effected from the results of this process. Our hypothesis is that a calcineurin inhibitor, tacrolimus, could prevent the accumulation and the decrease of the neuronal cells. Therefore, this immunosuppressive drug could be a candidate for an early treatment of Alzheimer disease. Materials and methods: Fifteen male Wistar albino rats were divided to three groups; control, Alzheimer, and Alzheimer+Tacrolimus. The Alzheimer group received an injection of streptozotocin intracerebroventricularly for the purpose of modelling the disease via generating free radicals leading a cognitive impairment. Alzheimer+Tacrolimus group first received an oral drug, a calcineurin inhibitor for 10 days afterwards prepared for the model as same as the Alzheimer group received. Finally, all groups performed the Morris water maze test for four days then sacrificed. For the aim of counting neurons in the hippocampus stereological methods, as well as for an evaluation of cellular response to stress in dentate gyrus, a c-Fos immunohistochemistry was performed. Results: According to the probe trial of Morris water maze test, the latency time was dramatically higher at both Alzheimer and Alzheimer+Tacrolimus group (p < 0.01). We confirmed these results with our stereology data. The results from stereology technique indicate that there was a neuronal decrease at the hippocampus regions in Alzheimer and Alzheimer+Tacrolimus group. Our outcomes from immunohistochemical data showed a significant increase in the number of c-Fos-positive cells in Alzheimer group when comparing with Alzheimer+Tacrolimus group (p < 0.001). Conclusion: There was none preventive effect for neuronal loss in the hippocampus under the effect of tacrolimus drug according to stereological results. However, tacrolimus administration may have reduced cellular stress and cell damage.
Citation Count: 9
Hippocampal neural cell loss in high-fat diet-induced obese rats-exploring the protein networks, ultrastructure, biochemical and bioinformatical markers
(Elsevier, 2021) Alkan, Isinsu; Altunkaynak, Berrin Zuhal; Gultekin, Guldal Inal; Baycu, Cengiz; Histoloji ve Embriyoloji / Histology and Embriology; Fizyoloji / Physiology
Objective: Obesity, which has become one of the main health problems, results from irregular and unhealthy nutrition. In particular, an increase in the intake of high-fat foods leads to obesity and associated disorders. It is noteworthy to specify that obese individuals have memory problems. This study aims to examine the effects of high-fat diet on hippocampus, with stereological, histopathological methods and STRING bioinformatic tool. Methods: Female Adult Sprague Dawley rats (n = 20) were equally divided into control (CONT) and high-fat diet (HFD) groups. The control group was given standard rat pellet feed, while the high-fat diet group was fed with a 40 % fat content for 2 months. Following the feeding program, rats were sacrificed. The collected blood samples were analyzed biochemically to determine the level of oxidative stress while performing a stereological and histopathological examination of the brain tissues. Functional protein-protein networks for BDNF, C-Fos, CAT, LPO, SOD and MPO by gene ontology (GO) enrichment analysis were evaluated. Findings: The number of neurons decreased in the HFD group compared to the CONT group. Damage to the histological structure of the hippocampus region; such as degenerate neurons, damaged mitochondria and extended cisterns of the endoplasmic reticulum was observed. Although C-Fos level and oxidative stress parameters increased in HFD group, BDNF level decreased. While BDNF and C-Fos were observed in pathways related to neuron death, oxidative stress and memory, BDNF was pronounced in the mitochondria, and C-Fos in the endoplasmic reticulum. Discussion: This study shows that changes in both BDNF and C-Fos levels in obesity due to high-fat diet increase oxidative stress and cause neuron damage in the hippocampus.
Citation Count: 10
Histological Study of The Healing of Traumatic Tympanic Membrane Perforation After Vivosorb and Epifilm Application
(Sage Publications inc, 2021) Yilmaz, Mahmut Sinan; Sahin, Elvan; Kaymaz, Recep; Altunkaynak, Berrin Zuhal; Akidil, Ayse Oznur; Yanar, Sevinc; Guven, Mehmet; Histoloji ve Embriyoloji / Histology and Embriology
Background: Untreated traumatic tympanic membrane perforations (TMPs) may lead to permanent perforations and hearing loss. There are many materials that have been previously used for repairing the TMPs. Aims and Objectives: The purpose of this study is to evaluate the clinical and histological effects of Vivosorb (Vv) and Epifilm on healing of TMPs in a rat model. Material and Methods: The posterior-inferior quadrant of the tympanic membranes (TMs) in right ears of 14 rats was perforated using a 20-g needle and then the animals were randomly divided into 2 equal groups (n = 7). The perforated right TMs were treated with either Vv (Vv group) or Epifilm (Ep group). The left TMs of 7 rats were perforated in same way and allowed to close spontaneously without any topical material applications (spontaneous closure group as sham control, SC). The left tympanic membranes of the other 7 rats were not perforated and used as normal controls (NC group). On postoperative 15th day, tympanic bullas were extracted from killed rats and examined morphometrically and histopathologically. Results: Perforation closure rate was 85.7% (6/7) in both Vv and SC groups. Perforations of Ep group closed in 7/7 (100%) ears. The thicknesses of the perforated membranes were increased in SC and especially Vv groups. Also, connective tissue fibrosis, blood clots, and epithelial degenerations were detected in SC and Vv groups. The mean fibroblastic reaction scores of Vv, Ep, and SC groups were 2.14(+), 0.57(+), and 1.71(+) respectively, on comparison with NC group. The mean neovascularization score was 1.42(+) in Vv group, 0.14(+) in Ep group, and 0.57(+) in SC group. Conclusion and Significance: Vivosorb and especially Epifilm can improve the healing process in traumatic TMPs and additionally, Epifilm might be more preferred for the treatment of TMPs because of causing lesser fibrosis.
Citation Count: 10
Histomorphometric changes in the placenta and umbilical cord during complications of pregnancy
(Taylor & Francis inc, 2018) Gueven, D.; Altunkaynak, B. Z.; Altun, G.; Alkan, I.; Kocak, I.; Histoloji ve Embriyoloji / Histology and Embriology
Pregnancy complications may cause morphological changes and circulation defects in the placenta, which may lead to morbidity and mortality in fetuses and newborns. We investigated structural changes in the placenta and umbilical cord under various abnormal maternal conditions. Placenta and umbilical cord specimens were obtained from pregnant women during labor at 37 - 42 weeks gestation. Volumetric measurements were made for each placenta and umbilical cord using the Cavalieri method. Significant differences were observed for volumetric densities of total villi, syncytial knots, intervillous vessels and perivillous fibrin deposition. We observed particular increases in the volumetric parameters of the pre-eclampsia group compared to the other groups. The tunica media of the umbilical arteries was increased significantly with intrahepatic cholestasis.
Citation Count: 0
Imiquimod Inhibits Proliferation of Serous Epithelial Ovarian Cancer Cells In Vitro: A Preliminary Study
(Springer india, 2020) Kokcu, Arif; Alper, Tayfun; Ogur, Gonul; Akar, Omer Salih; Ozdes, Emel Kurtoglu; Altunkaynak, Berrin Zuhal; Histoloji ve Embriyoloji / Histology and Embriology
Purpose Imiquimod, known as positive immune response modifier and stimulates local cytokine induction, has been used in therapy of genital warts via increasing local interferon and reducing human papillomavirus production. We aimed to investigate whether imiquimod has any effect on the proliferation of serous epithelial ovarian cancer cells in vitro. Methods The study was designed in two stages. The first stage was designed to evaluate co-culturing of serous epithelial ovarian cancer cells with the drug imiquimod versus cancer cells cultured with no drug. The second stage of the study was initiated with primary ovarian cancer cell culture growth. Imiquimod was applied in increasing concentrations to flasks full of each kind of cells. Also, histomorphometrical evaluation was made using an unbiased counting frame. Results Treatment of the primary cancer cell cultures with imiquimod in concentrations of 2.5 mu g/ml and 5.0 mu g/ml did not result in a significant effect on cell proliferation and the cell proliferation continued. Cell proliferation stopped and the cells detached at concentrations of 7.5 mu g/ml, especially 10.0 mu g/ml, 12.5 mu g/ml, and 25.0 mu g/ml, within 2-3 days after exposure to the drug. The anti-proliferative effect of imiquimod reached a maximum level at a concentration of 12.5 mu g/ml. Conclusions Imiquimod has a dose-dependent anti-proliferative impact on serous epithelial ovarian cancer cells in vitro.
Citation Count: 13
Investigation of the neuroprotective effects of thymoquinone on rat spinal cord exposed to 900 MHz electromagnetic field
(Elsevier, 2019) Yahyazadeh, Ahmad; Altunkaynak, Berrin Zuhal; Histoloji ve Embriyoloji / Histology and Embriology
Exposure to electromagnetic field in long-term use of cell phones has increased concerns about serious health problems. Our aim was to survey the possible effects of electromagnetic field radiation (60 min/day for 28 days) on the spinal cords of 12 weeks old rats. Further, we investigated whether the administration of thymoquinone (10 mg/kg/day) would protect the spinal cord tissue against the adverse effects of electromagnetic field or not. Twenty-four adult male Wistar albino rats were assigned randomly into four groups: control, electromagnetic field, thymoquinone and electromagnetic field + thymoquinone. The cervical spinal cords of all rats was evaluated using the stereological, biochemical and histological methods. The number of motor neurons were reduced in the electromagnetic field group compared to the control group (p < 0.05). Superoxide dismutase level was higher in the electromagnetic field group compared to the control group (p < 0.05). In the electromagnetic field + thymoquinone group, we found an increase in the number of motor neurons and decrease in superoxide dismutase activity compared to the electromagnetic field group (p < 0.05). Our histological findings also exhibit the remarkable architectural alterations. We speculated that electromagnetic field radiation induced the morphological and biochemical damage to the spinal cord tissue of rats. Administration of antioxidant, thymoquinone, also ameliorated such complications caused by electromagnetic field.
Citation Count: 0
Investigation of the Relationship Between HMGB1 and Obesity in the Adrenal Gland
(2022) Muhammed ERDAL; Işınsu Aydın Alkan; Emin Oztas; Berrin Zuhal ALTUNKAYNAK; Adem KOCAMAN; Histoloji ve Embriyoloji / Histology and Embriology
Aim: The interaction between obesity and increased production of pro-inflammatory cytokines results the existence of inflammation HMGB1 secreted from the adrenal gland can play a role in inflammation pathways. The aim of this study is to explain the link between HMGB1 and obesity in the adrenal gland. Material and Methods: In this study; eighteen female Wistar Albino rats were divided into two groups: untreated control group (n=8) and obese group (n=10). The rats in obese group were fed with high fat diet for ten weeks. Morphometric parameters of adrenal gland were assessed by using stereological techniques. The expression of high mobility group box protein 1 (HMGB1) in adrenal gland was evaluated. Results: At the end of the analyses; mean volumes of zona fasciculate, zona reticularis, and medulla were significantly increased in obese group. Also, the number of HMGB1 stained cells was significantly increased in the obese group in comparison to control group.Conclusion: The results suggest that obesity may be one of the reasons of inflammation and hypertrophy in the adrenal gland. HMGB1 may provide a novel perspective into the anti-inflammatory therapeutic strategies in obese patients.
Citation Count: 7
Is melatonin, leptin or their combination more effective on oxidative stress and folliculogenesis in the obese rats?
(Taylor & Francis inc, 2020) Kirikci, Gamze; Altunkaynak, Berrin Zuhal; Kaplan, Suleyman; Histoloji ve Embriyoloji / Histology and Embriology
In this study, we evaluated the effects of melatonin (Mel), leptin (Lep) or melatonin and leptin treatment on ovaries in control and obese rats. The animals were divided into control (NC), melatonin (NM), leptin (NL), melatonin?leptin (NML), obese (OC), obese?melatonin (OM), obese?leptin (OL), obese?melatonin?leptin (OML) groups. Body weights, peri-ovarian fat pads, volumetric parameters and numerical values of follicles were estimated. Also, the LH receptor (LHr) immune-positivity, catalase (CAT) and the myeloperoxidase (MPO) levels were determined. The body weight and peri-ovarian fat pads were significantly decreased following Mel (p?
Citation Count: 0
Is vagal stimulation or inhibition benefit on the regulation of the stomach brain axis in obesity?
(Taylor & Francis Ltd, 2022) Alkan, Isinsu; Altunkaynak, Berrin Zuhal; Kivrak, Elfide Gizem; Kaplan, Arife Ahsen; Arslan, Gulay; Histoloji ve Embriyoloji / Histology and Embriology
Objective:Possible effects of the vagus inhibition and stimulation on the hypothalamic nuclei, myenteric plexes and the vagus nerve were investigated. Methods:The female rats divided to the inhibition (INH), stimulation (STI) and, sham (SHAM) groups were fed with high fat diet (including 40% of energy from animal fat). After nine weeks, the rats were allowed to recover for 4 weeks in INH group. In STI group, the left vagus nerve stimulated (30 Hz/500 msn/30 sec.) starting 2nd post operative day for 5 minutes during 4 weeks. Healthy female rats used as control (CONT). Then, tissue samples were analyzed by biochemical, histological and stereological methods. Results:The mean number of the neurons in the arcuate nucleus of the INH group was significantly less; but, that is significantly more in the STI group compared to the other groups. The neuronal density of ventromedial nucleus in the STI group was higher; while the density in the INH group was lower than the other groups. In the dorsomedial nucleus, neuron density of the INH group was lower than the other groups. In terms of the myenteric plexus volumes, that of the INH group was lowest. The myelinated axon number in the INH group was significantly highest. The myelin sheath thickness and axon area of the INH group was significantly lower than the other groups. Discussion:The results of the study show that the vagal inhibition is more effective than the vagal stimulation on the weight loss in the obesity.
Citation Count: 13
Melatonin and sciatic nerve injury repair: a current perspective
(Dove Medical Press Ltd, 2018) Altunkaynak, Berrin Zuhal; Delibas, Burcu; Altun, Gamze; Deniz, Omur Gulsum; Histoloji ve Embriyoloji / Histology and Embriology
Peripheral nerve injury is an important clinical problem that can exert hazardous effects on the health of patients. For this reason, there are more studies conducted on the regeneration of the peripheral nerves via the usage of the nerves belonging to various animals with different types of lesions, ages, and by using different methods of assessment with regular follow-up. Contrary to data obtained through experimentation and clinical observation, no ideal way of treatment was found to increase the regeneration of the peripheral nerves. Finally, the effects of melatonin in the protection of peripheral nerves against trauma, especially the protection of sciatic nerve from pathological conditions, have come into attention in a wide group of scientists as there are beneficial effects of melatonin after surgery. While numerous studies indicate the melatonin's protective effects on the pathologies of nerves, there are also studies reporting its toxic effects on peripheral nerves. Melatonin is a widespread and crucial signaling molecule due to its features of free radical scavenging and anti-oxidation at both pharmacological and physiological conditions in vivo. In this context, although there are numerous studies elaborating the effects of melatonin in various tissues, its effects on peripheral nerves was documented in only a limited number of studies. The aim of this article was to perform a review of the knowledge in the literature on the subject of mostly beneficial or hazardous effects of melatonin on the repair of the damaged peripheral nerves.
Citation Count: 4
The morphometrical and immunohistochemical investigation of the effect of topiramate on liver and the role of neuropeptide Y receptor in an obese female rat
(Comenius Univ, 2020) Yahyazadeh, A.; Altunkaynak, B. Z.; Alkan, I; Histoloji ve Embriyoloji / Histology and Embriology
OBJECTIVE: We aimed to investigate the possible effect of topiramate (TOP, 0.02 mg/kg/day) on the livers in a high-fat diet (HFD)-induced obesity rat model. The other objective was to evaluate the relationship between TOP administration and NPY level using anti-NPY1R antibody. METHODS: Twenty-four adult female Wistar albino rats were randomly assigned into four equal groups as follow: control (CONT), obese (OBS), TOP, and OBS+TOP. All liver samples were investigated using the stereological analysis, as well as immunohistochemical and histopathological examination. RESULTS: The total number of hepatocytes was significantly decreased in the OBS+TOP group compared to the CONT group or the OBS group (p < 0.05). We found a significant increase in the mean volume of liver in the OBS group compared to the CONT group (p < 0.05). Also, the mean volume of liver was significantly decreased in the OBS+TOP group compared to the OBS group (p < 0.05). CONCLUSION: Taken together, our findings suggest that decreased liver volume is possibly attributed to TOP administration via setting the NPY level in the obese rats. Further, the side effects of TOP in combination with health risk of obesity may have led to an increase in hepatotoxicity and the subsequent hepatocyte loss (Fig. 7, Ref. 56). Text in PDF www.elis.sk
Citation Count: 7
Neuroprotective efficacy of luteolin on a 900-MHz electromagnetic field-induced cerebellar alteration in adult male rat
(Elsevier, 2020) Yahyazadeh, Ahmad; Altunkaynak, Berrin Zuhal; Histoloji ve Embriyoloji / Histology and Embriology
The adverse health consequences of exposure to electromagnetic field emitted from cell phone has recently raised public concerns worldwide. Also, the Global System for Mobile Communications (GSM) standard that operates in 900 MHz frequency is the most popular. Therefore, we aimed to investigate the adverse effect of exposure to 900 MHz EMF (1 h/day) on the cerebella of 12-week-old rats. We also evaluated the protective activity of luteolin (20 mu g/kg/day) against possible biological change in the cerebellar tissues exposed to EMF. Twenty-four male wistar albino rats were randomly assigned into four group of six rats: Control, EMF, EMF + luteolin, luteolin. Serological and biochemical analyses, as well as histopathological examination were performed on all cerebellar samples. We found that SOD (superoxide dismutase) level was significantly increased in the EMF group compared to the control group (p < 0.05). To the contrary, decreased SOD activity was detected in the EMF + luteolin group compared to control group (p < 0.05). The total number of Purkinje and granular cells was significantly decreased in the EMF group compared to the control group (p < 0.05). In the EMF + luteolin group, the total number of Purkinje and granular cells was significantly higher than the EMF group (p < 0.05). Histopathological evaluation also showed destructive damage to the architectures of cerebellar tissues. Our results suggest that exposure to EMF may cause cellular damage to the rat cerebellum. Further, the improvement of cerebellar damage may have resulted from antioxidant efficacy of luteolin by alleviating oxidative stress.
Citation Count: 0
Periferik Sinir Yaralanmaları ve Rejenerasyonu
(2022) Berrin Zuhal ALTUNKAYNAK; Işınsu Aydın Alkan; Esra BEKAR; Histoloji ve Embriyoloji / Histology and Embriology
Periferik sinirler merkezi sinir sistemi ve periferal organlar arasındaki motor ve duyu uyarımını sağlayan hedef organda uyardıkları fonksiyonlara göre isimledirilen çeşitli sinir liflerinden oluşan sistemdir. Travmalara oldukça açık bulunan periferik sinirlerde farklı sebepler ile yaralanmalar gözlemlenir. Bu şekilde periferik sinirlerde oluşabilecek hasar kişinin motor ve duyu uyarımını olumsuz etkilemektedir. Periferal yaralanmaların ardından perifrerik sinirde hasara bağlı olarak dejeneratif süreçler başlatılır. Aksonal devamlılığı kesintiye uğratacak derecedeki yaralanmalarda aksonda sinir fonksiyonunun devamlılığı için gereken metabolik olaylar gerçekleşemediği için distal kısımlar dejenerasyona uğrar. Periferik sinir rejenerasyonunda Schwann hücre dediferansiyasyonu, proliferasyonu ve remiyelinizasyon önemli rol oynar. Rejeneratif süreç ise oldukça fazla faktörün bir arada çalıştığı bir süreçtir. Bu derlemede, periferik sinirde meydana gelen yaralanmaların ardından gerçekleşen rejenerasyon süreci, ayrıca rejenerasyona etki eden nörotrofik faktörler ve tedavi sürecinde kullanılan farklı metotların etki mekanizmalarına değinilmiştir.
Citation Count: 0
Potential Effects of Stem Cells Derived from the Peripheral Nerve and Adipose Tissue after the Nerve Crush Injury in Control and Obese Rats
(Taylor & Francis inc, 2022) Kustepe, Elif Kayhan; Altunkaynak, Berrin Zuhal; Alkan, Isinsu; Kivrak, Elfide Gizem; Yildiran, Alisan; Geuna, Stefano; Histoloji ve Embriyoloji / Histology and Embriology
Aim of this study is to investigate effects of stem cells derived from the peripheral nerve and adipose tissues following the nerve crush injury in control and obese rats. For this aim, 41 Wistar Albino female rats were separated into eight equal groups; non-obese control (NOC) obese control (OC), non-obese injury (NOH), obese injury (OH), non-obese adipose (NOY), obese adipose (OY), non-obese nerve (NOPS), obese nerve (OPS). At the end of 8 weeks, all experimental animals without control groups were subjected to nerve crush procedure and sciatic nerve or fat stem cell homogenates were injected on the treatment group rats, and then, recovery process has been observed and histopathological, stereological, electrophysiological analyses and bioinformatic evaluation were made on removed sciatic nerves. Stereological results showed that adipose homogenate gave more successful results than peripheral nerve homogenates in the NOY group in comparison to the NOPS group in terms of myelinated axon number. Peripheral nerve homogenate has shown more successful results in the OPS group in comparison to the OY group. The number of unmyelinated axons was increased following treatment with adipose tissue homogenate in NOY and OY groups. In terms of myelin sheath thickness; we detected that treatments by peripheral nerve and especially adipose tissue homogenates lead to increase in the thickness of the axons of the peripheral nerves belong to the control and obese injury groups. All results showed that mesenchymal stem cell treatment by fresh tissue homogenates is successful in peripheral nerve regeneration and fat tissue is a considerable source of the stem cells for clinical applications.