Kevser Tanbek

Resveratrol successfully treats experimental endometriosis through modulation of oxidative stress and lipid peroxidation

BACKGROUND AND AIMS The purpose of this study was to investigate the potential therapeutic efficiency of resveratrol in the treatment of experimental endometriosis in rats. SETTINGS AND DESIGN Experimental study was carried out in a University hospital. MATERIALS AND METHODS Endometriosis was surgically induced in 24 female rats. Four weeks after this procedure, the viability and dimensions of the endometriosis foci were recorded. Rats were then randomly divided into three groups: (1) Control group (n = 8); (2) low dose (10 mg/kg) resveratrol group (n = 8); (3) high dose (100 mg/kg) resveratrol group (n = 8). At the end of the 7-day treatment, blood samples were taken and laparotomy was performed. The endometrial implants were processed for biochemical, histological and immunohistochemical studies. STATISTICAL ANALYSIS USED The Kruskal-Wallis H test and one-way ANOVA test were used. RESULTS Resveratrol-treated rats showed significantly reduced endometriotic implant volumes (P = 0.004). After treatment, a significant and dose-dependent increase in activities of superoxide dismutase and glutathione peroxidase in serum and tissue of the rats in Group 2 and Group 3 was detected. Similarly, serum and tissue malonyl dialdehyde levels and tissue catalase levels were significantly higher in Group 3 than that of control animals. Histological scores and proliferating cell nuclear antigen expression levels were also significantly reduced in Group 2 and Group 3 than that of control group. CONCLUSION In a rat endometriosis model, resveratrol showed potential ameliorative effects on endometriotic implants probably due to its potent antioxidative properties.

Protective Effects of Apocynin on Cisplatin-induced Hepatotoxicity in Rats

BACKGROUND AND AIMS Despite it being a highly potent antineoplastic drug, cisplatin has important toxic adverse effects limiting its use such as nephrotoxicity, neurotoxicity and ototoxicity. It is thought that cisplatin-induced hepatotoxicity is caused by oxidative stress resulting from increased reactive oxygen species (ROS). Apocynin (APO) exerts its antioxidant effect by reducing ROS production via inhibition of NADPH oxidase. The present study intended to demonstrate effects of cisplatin on hepatic pro-oxidant/antioxidant systems and to investigate protective effects of APO against cisplatin-induced hepatotoxicity. METHODS Rats were randomly assigned into four groups (n = 8 each): a) control group; b) single dose of cisplatin (5 mg/kg); c) APO group (20 mg/kg on three consecutive days; i.p.); and d) APO plus cisplatin group. Liver tissue was assessed in all groups by biochemical and histopathological means. Also, serum alanine transaminase (ALT), aspartate transaminase (AST) and alkaline phosphatase levels were studied in all groups. RESULTS When cisplatin group was compared to controls, it was seen that lipid peroxidation product, total oxidant status and ALT levels were markedly increased, whereas superoxide dismutase and glutathione peroxidase levels were overtly decreased. APO therapy markedly prevented cisplatin-induced harmful changes in liver. Our histopathological findings such as central vein dilatation, perivenuler and periportal sinusoidal dilatation, parenchymal inflammation, vacuolar changes in hepatocytes, biliary duct proliferation and caspase-3 positive hepatocytes were in accordance with the biochemical changes. CONCLUSION In light of these results, it is our thought that APO has a protective role against cisplatin-induced hepatotoxicity at both biochemical and histopathological levels.

Melatonin's protective effect on the salivary gland against ionized radiation damage in rats

OBJECTIVES The aim of this study was to examine the effects of melatonin on ionized radiation-induced salivary gland damage using an experimental model. MATERIALS AND METHODS Thirty-two rats were randomized into four groups: (i) the control group (C, n = 8) that received intraperitoneal (i.p.) 0.9% NaCl; (ii) the melatonin group (M, n = 8) that received i.p. 5 mg/kg melatonin; (iii) the radiotherapy group (RT, n = 8) that underwent irradiation; (iv) the melatonin plus radiotherapy group (M+RT, n = 8) that received i.p. 5 mg/kg of melatonin, followed by irradiation 30 min later; and (v) the radiotherapy plus melatonin group (RT+M, n = 8) that received irradiation followed by i.p. 5 mg/kg of melatonin 30 min later. The medications and irradiation were administered for 5 days and the salivary glands of the rats were excised 10 days later; the histopathological changes in the salivary glands were assessed and biochemical analyses were conducted (tissue levels of malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx), reduced glutathione (GSH), total antioxidant status (TAS), total oxidant status (TOS), and oxidative stress index (OSI)). RESULTS Regardless of whether melatonin was administered before or after radiotherapy, melatonin decreased the radiation-induced parotid and submandibular histological damage. In addition, regardless of whether administration occurred before or after radiotherapy, melatonin decreased oxidative stress markers, such as MDA, TOS, and OSI. On the contrary, levels of antioxidative markers, such as CAT and GPx, were increased by melatonin. CONCLUSIONS Melatonin may have a significant protective effect on salivary gland damage secondary to ionizing radiation.

A comparative study on oxidative and antioxidative markers of serum and follicular fluid in GnRH agonist and antagonist cycles

ObjectiveTo determine whether concentrations of oxidative stress markers of follicular fluid and serum are different in GnRH agonist protocol from GnRH antagonist protocol.Material and methodThis was a cross-sectional study. Eighty-four women undergoing controlled ovarian stimulation with either GnRH agonist (n = 39) or GnRH antagonist protocols (n = 45) for IVF/ICSI treatment were assigned by a physician. Blood was obtained at the time of oocyte retrieval, and follicular fluid (FF) from the mature follicles of each ovary was centrifuged and frozen until analysis. Malondialdehyde (MDA), nitric oxide (NO), protein carbonyl (PC), hydroxyl proline (OH-P), sodium oxide dismutase (SOD), reduced glutathione (GSH), glutathione peroxidase (GSH-Px), adenosine deaminase (ADA) and xanthine oxidase (XO) were assessed in the serum and follicular fluid of each participants.ResultsThe mean serum concentrations of GSH-Px, GSH and MDA were lower in the GnRH antagonist group compared to GnRH agonist group, but mean serum SOD was higher in the GnRH antagonist group. The mean follicular SOD, ADA and NO were higher in GnRH antagonist group than GnRH agonist group. The IVF/ICSI outcomes were similar in both groups.Conclusion(s)GnRH antagonist protocol is associated with increased oxidative stress. The relation of GnRH analogues with oxidative stress and its implication in follicular growth needs to be addressed in further studies.

Effects of dexpanthenol on acetic acid‑induced colitis in rats

While the pathogenesis of acetic acid (AA)-induced colitis is unclear, reactive oxygen species are considered to have a significant effect. The aim of the present study was to elucidate the therapeutic potential of dexpanthenol (Dxp) on the amelioration of colitis in rats. Group I (n=8; control group) was intrarectally administered 1 ml saline solution (0.9%); group II [n=8; AA] was administered 4% AA into the colon via the rectum as a single dose for three consecutive days; group III (n=8; AA + Dxp) was administered AA at the same dosage as group II from day 4, and a single dose of Dxp was administered intraperitoneally; and group IV (n=8; Dxp) was administered Dxp similarly to Group III. Oxidative stress and colonic damage were assessed via biochemical and histologic examination methods. AA treatment led to an increase in oxidative parameters and a decrease in antioxidant systems. Histopathological examination showed that AA treatment caused tissue injury and increased caspase-3 activity in the distal colon and triggered apoptosis. Dxp treatment caused biochemical and histopathological improvements, indicating that Dxp may have an anti-oxidant effect in colitis; therefore, Dxp may be a potential therapeutic agent for the amelioration of IBD.

Inhibition of NADPH oxidase by apocynin promotes myocardial antioxidant response and prevents isoproterenol-induced myocardial oxidative stress in rats

Abstract Preventive and/or therapeutic interventions for ischemic heart disease have gained considerable attention worldwide. We investigated the mechanism(s) underlying cardioprotection of apocynin (APO) and whether it attenuates isoproterenol (ISO)-induced myocardial damage in vivo. Thirty-two male Wistar Albino rats were randomised into four groups (n = 8 for each group): Group I (Control); Group II (ISO), ISO was given intraperitoneally (ip) (150 mg/kg/d) daily for 2 consecutive days; Group III (APO + ISO), APO was applied ip 20 mg/kg 30 min before the first ISO administration and continued for the next 2 d after the second ISO administration; Group IV (ISO + APO), after the ISO treatment on days 1 and 2, 20 mg/kg APO was given ip on days 3 and 4. Cardioprotective effects of APO were evaluated by biochemical values, histopathological observations and the antiapoptotic relative proteins. Mean blood pressure, heart rate, and electrocardiography (ECG) were also monitored. Malondialdehyde (MDA), superoxide dismutase (SOD), catalase (CAT), reduced glutathione (GSH), total oxidant status (TOS), total antioxidant capacity (TAC), oxidative stress index (OSI), caspase-3 and connexin 43 levels were determined. Major ECG changes were observed in the ISO-treated rats. MDA, TOS, OSI and creatine kinase levels decreased and SOD, CAT, GSH and TAC levels increased, indicating that APO reduced cardiac injury and oxidative stress compared with controls. APO also decreased the number of cardiomyocytes with pyknotic nuclei, inflammatory cell infiltration, intracytoplasmic vacuolisation and myofibrils. APO provides preventive and therapeutic effects on ISO-induced myocardial injury in rats by inhibiting reactive oxygen species production, blocking inflammation and enhancing antioxidant status.

Effects of Molsidomine on Retinopathy and Oxidative Stress Induced by Radiotheraphy in Rat Eyes

ABSTRACT Purpose: To determine the role of Molsidomine in preventing radiation-induced retinopathy after head and neck region irradiation of rats with a single radiation dose of 15 Gy. Materials and Methods: Male Wistar albino rats were randomly grouped into five as follows: (1) control group rats, which were applied through an intraperitoneal (i.p.) vehicle without radiotherapy (RT); (2) RT group rats received a single dose of 15 Gy irradiation and after daily 0.1 ml vehicle i.p. for 5 consecutive days; (3) molsidomine (MOL) group rats were treated for 5 consecutive days by i.p. with 4 mg/kg/day MOL; (4) irradiation plus MOL group (RT+MOL) rats received irradiation and after 10 days single daily i.p. dose of MOL for 5 consecutive days; and (5) MOL+RT group rats were treated for 5 consecutive days by i.p. with MOL before RT. At the end of the work the rats were sacrificed under high-dose anesthesia on the 16th day and then eye tissues were taken for histopathological, immunohistochemical (caspase-3), and biochemical analyses (superoxide dismutase [SOD], glutathione peroxidase [GSH], and malondialdehyde [MDA]). Results: RT significantly decreased both the content of GSH and the activity of SOD, and significantly increased the production of MDA level in the rat eyes. MOL treatment significantly increased the SOD and GSH levels and significantly decreased the MDA production (p < 0.0001). In addition, RT significantly increased the number of ganglion cells (GCs; p = 0.001), whereas especially pretreatment with MOL improved (p = 0.013). RT led to significant retinopathy formation, and MOL therapy protected the retina from radiation-induced retinopathy (p < 0.0001). Conclusions: We suggest that MOL is a powerful antioxidant and free radical scavenger that prevents the rat eyes from radiation-induced retinopathy and oxidative stress.

Beneficial effects of dexpanthenol on mesenteric ischemia and reperfusion injury in experimental rat model

ABSTRACT Background and aim It has been reported that intestinal ischemia–reperfusion (I/R) injury results from oxidative stress caused by increased reactive oxygen species. Dexpanthenol (Dxp) is an alcohol analogue with epitelization, anti-inflammatory, antioxidant, and increasing peristalsis activities. In the present study, the aim was to investigate protective and therapeutic effects of Dxp against intestinal I/R injury. Materials and methods Overall, 40 rats were assigned into five groups including one control, one alone Dxp, and three I/R groups (40-min ischemia; followed by 2-h reperfusion). In two I/R groups, Dxp (500 mg/kg, i.m.) was given before or during ischemia. The histopathological findings including apoptotic changes, and also tissue and serum biochemical parameters levels, were determined. Oxidative stress and ileum damage were assessed by biochemical and histological examination. In the control (n = 8) and alone Dxp (n = 8; 500 mg/kg, i.m. of Dxp was given at least 30 min before recording), groups were incised via laparotomy, and electrical activity was recorded from their intestines. In this experiment, the effect of Dxp on the motility of the intestine was examined by analyzing electrical activity. Results In ileum, oxidant levels were found to be higher, while antioxidant levels were found to be lower in I/R groups when compared with controls. Dxp approximated high levels of oxidants than those in the control group, while it increased antioxidant values compared with I/R groups. Histopathological changes caused by intestinal I/R injury and histological improvements were observed in both groups given Dxp. In the Dxp group, electrical signal activity markedly increased compared with the control group. Conclusions Here, it was seen that Dxp had protective and therapeutic effects on intestinal I/R injury and gastrointestinal system peristaltism.

Nuclear transcription factor-kappa beta-dependent ultrastructural alterations within the placenta and systemic inflammatory activation in pregnant patients with hemolysis, elevated liver functions and low thrombocyte count (HELLP) syndrome: a case–control study

Objective: Preeclampsia appears to be associated with a higher extent of inflammation than in uncomplicated pregnancies. We aimed to test whether this was the case in patients with hemolysis, elevated liver functions and low platelet count (HELLP) syndrome and to clarify the contribution of placental and systemic inflammatory variables in the development of this syndrome. Materials and methods: Thirty healthy pregnant women (control group) and 20 patients with HELLP syndrome (study group) were included in the study. Placental inflammatory activity was evaluated by quantifying immunohistochemically the levels of p65/RelA expression of nuclear transcription factor-kappa beta (NF-kB) in paraffin-embedded tissue samples. In addition, ultrastructural changes in placental morphology in HELLP patients were evaluated by transmission electron microscopy (TEM). The serum concentrations of myeloperoxidase (MPO) and C-reactive protein (CRP) were also measured and compared. Results: p65/RelA immunoexpression and serum MPO and CRP levels were significantly higher in patients with HELLP syndrome (p < 0.05). TEM of placenta in the study group revealed severely vacuolized syncytiotrophoblasts, irregular basal lamina and damaged capillary endothelium when compared with the placenta of control subjects. Conclusion: Our results suggest that over-expression of placental NF-kB is correlated with elevation of serum inflammatory markers and placental ultrastructural changes, which may point to an important role of local and systemic inflammatory activation in the pathogenesis of HELLP syndrome.

The Effect of Dexpanthenol on Ototoxicity Induced by Cisplatin

Objectives This study was aimed to investigate the protective effects of dexpanthenol (Dxp) on against cisplatin-induced ototoxicity. Methods To examine this effect, distortion product otoacoustic emissions (DPOAEs) measurements and serum levels of oxidative and antioxidant status (including malondialdehyde, superoxide dismutase, catalase, glutathione, glutathione peroxidase, total oxidant status, total antioxidant status, and oxidative stress index) were evaluated. Thirty-two adult female Wistar albino rats were randomly divided into 4 equal groups; control (K), cisplatin (C), cisplatin plus Dxp (CD), and Dxp (D). In all groups DPOAEs measurements, between 996 and 10,078 Hz as DPOAEs and input/output functions, were performed on days 0, 1th, 5th, and 12th. Prior to death, the last DPOAEs measurements and blood samples were taken. Results In the C group, statistically significant differences were detected at all frequencies between 0 and 5 days and 0 and 12 days measurements (P<0.05). Serum level of oxidant and antioxidant status were detected statistically significantly changed in this group versus K group (P<0.05). Contrary to the C group, in the CD group hearing ability was seen largely preserved at many frequencies and serum levels of all biochemical parameters were shifted toward normal values, similar to the K group. No significant differences were detected in the either D or K group’s measurements. Conclusion According to these results, Dxp may prevent cisplatin-induced ototoxicity.