PubMed İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.14627/8
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Article Protective Effects of Lactobacillus Rhamnosus GG Against Methotrexate-Induced Oxidative Renal Toxicity(Springer, 2026) Yanardag, Refiye; Bayrak, Bertan Boran; Sener, Goksel; Almurad, Bade; Donmez, Muhammet OguzhanMethotrexate (MTX) is commonly prescribed for various malignant and autoimmune conditions, but it can cause significant oxidative and functional impairment in renal tissue. Lactobacillus rhamnosus GG. (LGG) is a well-known probiotic with biological activities that support antioxidant balance. This study investigated the impact of LGG on MTX-induced kidney damage. Male Sprague-Dawley rats were divided into four groups: physiological saline-treated control group; a group receiving MTX alone; a group receiving MTX alongside a low dose of LGG; and a group receiving MTX alongside a high dose of LGG. MTX was administered as single dose (20 mg/kg/bw) intraperitoneally and LGG (low dose 1 x 10(9) CFU/day and high dose 5 & times; 10(9) CFU/day, respectively) orally for five days. On day six, blood and kidney samples were collected and examined for oxidative indicators, enzymatic antioxidant responses, and renal functional markers. MTX significantly increased in glomerular filtration markers in serum and elevated key indicators of oxidative stress in renal tissues. More so, MTX demonstrated to disrupt renal ionic homeostasis, such as declined sodium/potassium-ATPase, paraoxonase, and increased lactate dehydrogenase, carbonic anhydrase, xanthine oxidase, myeloperoxidase, and arginase activities. In contrast, LGG supplementation has been shown to effectively reverse all MTX-induced biochemical alterations in both serum and renal tissue. We can suggest that LGG can provide significant protection against oxidative renal toxicity induced by MTX in rats.Article Protective Effects of L-Theanine against Bisphenol A-Induced Oxidative Stress and Gut Microbiota Disruption in Wistar Rats(Springer, 2026) Sener, Azize; Marzi, Mahdi; Sener, Goksel; Donmez, Muhammet OguzhanBackground Gut microbiota homeostasis plays a central role in maintaining intestinal redox balance and immune regulation. Bisphenol A (BPA), a widely distributed environmental contaminant, has been associated with oxidative stress, inflammatory responses, and disturbances in intestinal microbial communities. L-theanine (LTN), a bioactive amino acid naturally present in green tea, possesses well-documented antioxidant and anti-inflammatory properties; however, its potential protective role against BPA-induced intestinal injury has not been fully clarified. Methods and Results In the present study, female Wistar albino rats were randomly allocated into three groups: control, BPA (50 mg/kg/day), and BPA + LTN (100 mg/kg/day) and treated for 30 days. Oxidative stress and inflammatory responses in intestinal and colonic tissues were assessed by measuring malondialdehyde (MDA), reduced glutathione (GSH) levels and myeloperoxidase (MPO), catalase (CAT) activities. BPA exposure significantly increased MDA (p < 0.001) level and MPO (p < 0.001) activity while reducing GSH content (p < 0.001) and CAT activity (p < 0.001) compared with the control group. Compared to the BPA group, LTN treatment led to significant changes in MDA, MPO, and GSH levels in both tissues. MDA and MPO levels were significantly reduced in the intestine and colon tissues of the BPA + LTN group (p < 0.001). GSH and CAT levels were significantly increased in both the intestine and colon compared to the BPA group (p < 0.001). In addition, fecal microbiota composition was analyzed using 16 S rRNA gene sequencing, with taxonomic profiling performed at the phylum, genus and species levels. BPA exposure was associated with reduced microbial stability and compositional shifts within the gut microbiota, whereas LTN treatment partially restored microbial richness and community structure. Conclusions Collectively, these findings indicate that LTN alleviates BPA-induced intestinal oxidative stress and microbiota dysbiosis, suggesting its potential as a protective dietary compound against environmental toxicant-related intestinal injury.Article Modulation of Brain Antioxidant Defense, Inflammation, and SIRT1 Activity by a Sunflower Oil-Based High-Fat Diet: Protective Role of L-Arginine in Rats(Springer, 2026) Şekerler, Turgut; Şener, Azize; Çavuşoğlu, Nuray; Doğan, ÖzgeBackgroundChronic consumption of omega-6-enriched dietary fat may disturb brain redox balance and neuroinflammatory homeostasis. Among the sirtuins, sirtuin 1 (SIRT1) exerts critical neuroprotective functions by suppressing oxidative stress and inflammatory signaling; however, the impact of sunflower oil-based high-fat diets (SO-HFD) on brain SIRT1 activity has not been investigated.ObjectiveThis study aimed to investigate the effects of SO-HFD on oxidative stress parameters, inflammatory markers, and SIRT1 activity in rat brain tissue, and to evaluate the potential modulatory role of L-arginine supplementation.MethodsFour-week-old female Sprague-Dawley rats were allocated into three groups: control, SO-HFD, and SO-HFD + L-arginine. Both SO-HFD groups were fed a diet containing sunflower oil for 16 weeks; from week 10 onward, 1.5% L-arginine was supplemented in the drinking water of the SO-HFD + L-arginine group. Following the 16-week protocol, serum and brain specimens were collected. Serum biochemical parameters and adiponectin were quantified; brain homogenates were assayed for lipid peroxidation (MDA), reduced glutathione (GSH), protein thiols (protein-SH), nitric oxide (NO), tumor necrosis factor-alpha (TNF-alpha) levels, and SIRT1 activity.ResultsAlthough brain MDA levels were not significantly elevated, SO-HFD animals exhibited reduced GSH and protein-SH content together with diminished SIRT1 activity. The SO-HFD increased TNF-alpha and NO levels. L-arginine supplementation decreased MDA and increased GSH, protein-SH, and SIRT1 activity. L-arginine also suppressed TNF-alpha levels in brain tissue compared to the SO-HFD group. NO levels in the SO-HFD + L-arginine group were lower than in the SO-HFD group, though not significantly.ConclusionThese findings suggest that chronic exposure to an omega-6-dominant dietary environment disturbs redox regulation and inflammatory balance in brain tissue, accompanied by reduced SIRT1 activity. L-arginine may attenuate cerebral oxidative stress and neuroinflammation by reinforcing endogenous antioxidant mechanisms, highlighting its potential as a nutritional strategy against SO-HFD-induced brain oxidative stress.Article Low Dose Ionising Radiation Elicits MPTP Comparable Alterations in Locomotor Function, Oxidative Balance and Mitochondrial Homeostasis in Zebrafish Embryos(Nature Portfolio, 2025) Cahide, Ezgi; Bayramov, Aydas; Beler, Merih; Cansiz, Derya; Unal, Ismail; Egilmezer, Gizem; Yalcinkaya, Sebnem ErcalikPrenatal exposure to environmental factors including low-dose ionising radiation and neurotoxins may disrupt the oxidant-antioxidant balance. Our aim was to assess the effects of exposure to low-dose ionising radiation (LDIR) and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP), which is a neurotoxin used to model Parkinson's disease (PD), on developing zebrafish embryos, focusing on the oxidant-antioxidant system and markers of mitochondrial damage associated with PD. Zebrafish embryos were divided into four groups: control, LDIR, MPTP, and LDIR combined with MPTP (LDIR + MPTP). A dental x-ray unit (60 kVp, 7 mA) was used for the exposures. The 0.08 s LDIR exposure was measured as 0.065 mGy using optically stimulated dosimeters. At the end of 72 h after fertilization, locomotor activities, acetylcholine esterase (AChE) activity, oxidative stress and antioxidant status were assessed. Expressions of genes associated with in PD as markers of mitochondrial damage (pink1, parkin, dj1 and lrrk2) were determined by RT-PCR. Developmental toxicity was observed in all exposure groups as evidenced by pericardial edema, yolk sac edema and spinal curvature. LDIR exposure in zebrafish embryos affected oxidative and mitochondrial stress markers, as well as locomotor activity and AChE as a marker of cognitive function at levels comparable to the MPTP exposure. Our study is the first to determine the effects of LDIR from a dental x-ray unit on the response to MPTP, and we aim to further elucidate the mechanism of these changes observed particularly in the LDIR + MPTP group.Article The Effect of Myrtus Communis L. Extract on Nephrolithiasis Model in Rats(Kare Publishing, 2024) Ertas, B.; Dorucu, D.; Gulerturk, O.; Sen, A.; Cevik, O.; Cetinel, S.; Sener, G.; Eker, Pinar; Akgün, Asuman; Sener, Tarik EmreOBJECTIVE: Nephrolithiasis is a common urological disease that can lead to renal failure. Oxidative stress has been shown to be a contributing factor for nephrolithiasis and many agents have been studied to prevent and treat oxidative stress-related nephrolithiasis and renal damage. Myrtus communis (MC) extract has been shown to be an important antioxidant in different animal models. In this study, MC extract was administered preventively or therapeutically to rats with kidney stones, and its effectiveness was investigated. METHODS: Wistar albino rats were divided into four groups (n=8); control (C), ethylene glycol (EG), EG+preventive MC, and EG+curative MC groups. The nephrolithiasis model was created by adding 0.75% EG to drinking water for 8 weeks. Ultimately, 24-hour urine was collected to measure calcium, citrate, and creatinine levels. After decapitation, kidney tissues were harvested for histological analyses, measurement of osteopontin and 8-hydroxydeoxyguanosine (8-OHdG) levels, and N-acetyl-β-glucosaminidase (NAG), myeloperoxidase (MPO) and caspase-3 activities. RESULTS: In 24-hour urine samples, calcium, citrate and creatinine levels were decreased in the EG group, while oxalate levels were increased and in treatment groups these parameters returned to control levels. MPO, 8-OHdG, caspase-3 and NAG activity were significantly increased in tissue and these changes were reversed in both MC groups. Histological findings also supported the biochemical parameters. CONCLUSION: MC can reduce oxidative stress and histopathological changes in kidney tissues in rat nephrolithiasis model when used as either a preventive or therapeutic agent. If supported with further clinical trials, MC might have clinical implications in preventing oxidative renal cell injury and ultimately kidney stone formation. © 2024 by Istanbul Provincial Directorate of Health.Article Citation - WoS: 2Citation - Scopus: 3Petroselinum Crispum Extract Prevents Scopolamine-Induced Lens Damage in Rats(Wiley-v C H verlag Gmbh, 2023) Ertik, Onur; Pazarbasi, Seren Ede; Sener, Goksel; Sacan, Ozlem; Yanardag, RefiyeAlzheimer's disease (AD) is a neurodegenerative disease that occurs especially in advanced ages. It reduces the quality of life of both the patient and their relatives. In addition to its primary effects, AD causes metabolic defects and tissues are damaged due to these effects. Oxidative stress damages cells by disrupting antioxidant/oxidant balance in many tissues, especially due to AD. In individuals with AD and the elderly, lens tissue is damaged due to oxidative stress and may cause vision loss. Therefore, it is very important to investigate herbal products that both prevent/cure AD and reduce AD-related oxidative stress, as they may have fewer side effects. In this study, the protective effects of parsley (Petroselinum crispum) extract on lens tissues of an experimental AD model induced by scopolamine were examined and evaluated through biochemical parameters. The result of biochemical experiments and principal component analysis, was observed that parsley extract had a therapeutic effect by reducing oxidative stress in lens tissues of experimentally induced AD rats. It can be suggested that the phenolic and flavonoid-rich content of parsley extract may have caused the reduction of oxidative damage in lens tissues and can be used to protect lens tissue against oxidative stress due to AD disease.Article Citation - WoS: 2The Effect of <i>myrtus Communis</I> L. Extract on Nephrolithiasis Model in Rats(Kare Publ, 2024) Ertas, Busra; Dorucu, Dogancan; Gulerturk, Oznur; Sen, Ali; Cevik, Ozge; Cetinel, Sule; Sener, GokselOBJECTIVE: Nephrolithiasis is a common urological disease that can lead to renal failure. Oxidative stress has been shown to be a contributing factor for nephrolithiasis and many agents have been studied to prevent and treat oxidative stress-related nephrolithiasis and renal damage. Myrtus communis (MC) extract has been shown to be an important antioxidant in different animal models. In this study, MC extract was administered preventively or therapeutically to rats with kidney stones, and its effectiveness was investigated. METHODS: Wistar albino rats were divided into four groups (n=8); control (C), ethylene glycol (EG), EG+preventive MC, and EG+curative MC groups. The nephrolithiasis model was created by adding 0.75% EG to drinking water for 8 weeks. Ultimately, 24-hour urine was collected to measure calcium, citrate, and creatinine levels. After decapitation, kidney tissues were harvested for histological analyses, measurement of osteopontin and 8-hydroxydeoxyguanosine (8-OHdG) levels, and N-acetyl-beta-glucosaminidase (NAG), myeloperoxidase (MPO) and caspase-3 activities. RESULTS: In 24-hour urine samples, calcium, citrate and creatinine levels were decreased in the EG group, while oxalate levels were increased and in treatment groups these parameters returned to control levels. MPO, 8-OHdG, caspase-3 and NAG activity were significantly increased in tissue and these changes were reversed in both MC groups. Histological findings also supported the biochemical parameters. CONCLUSION: MC can reduce oxidative stress and histopathological changes in kidney tissues in rat nephrolithiasis model when used as either a preventive or therapeutic agent. If supported with further clinical trials, MC might have clinical implications in preventing oxidative renal cell injury and ultimately kidney stone formation.Article Citation - Scopus: 1Ethanolic Extract of Cotinus Coggygria Leaves Attenuates Crystalluria and Kidney Damage in Ethylene Glycol-Induced Urolithiasis in Rats(Kare Publishing, 2023) Gumru, S.; Ozgur, G.; Ertas, B.; Sen, A.; Eker, P.; Sener, T.E.; Sener, G.OBJECTIVE: Nephrolithiasis is a common cause of kidney insufficiency. Nephrolithiasis is proven to be the result of various biochemical and inflammatory processes that result in crystal formation and subsequent aggregation. Cotinus coggygria L. (CCog) is a plant extract which has been used as a Turkish remedy for kidney stones. With this study, we planned to evaluate the effects of CCog extract in ethylene glycol (EG)-induced nephrolithiasis model in rats. METHODS: The study group comprised 32 Wistar albino rats which were divided into Control (C), EG, CCog Prophylaxis (CC+EG+CC), and CCog Treatment (EG+CC) groups. Stone formation was induced by adding EG (0.75%) into rat’s drinking water. Normal drinking water was given to Control group for 8 weeks. Throughout the study period of 8 weeks, EG group was given only EG (0.75%) and CC+EG+CC group was given both EG and CCog. In EG+CC group, EG (0.75%) was given for 8 weeks whereas CCog was given for the past 4 weeks. After the 8th week, 24-h urine samples were collected. Rats were then sacrificed and kidney tissue samples were harvested. RESULTS: Metabolites (calcium, citrate) and creatinine in 24 h urine samples were decreased in CC+EG+CC and EG+CC groups. While hyperoxaluria was observed in the EG group, oxalate levels were similar to control levels in the P-CCog and C-CCog groups. The N-acetyl-β-glucosaminidase and myeloperoxidase activities were both increased in EG group and these parameters were significantly decreased on CCog treatment. CONCLUSION: We can conclude that C. coggygria extract can have beneficial effect on lowering concentration of stone-forming metabolites in urine and consequently protect renal tissues from damage due to nephrolithiasis. C. coggygria extract can be considered as a potential prophylactic and therapeutic option in high-risk stone formers. Furthermore, our data confirm ethnobotanical use of CC against nephrolithiasis. © 2023 by Istanbul Provincial Directorate of Health.Article Citation - WoS: 4Citation - Scopus: 4Whey Protein Concentrate Ameliorates the Methotrexate-Induced Liver and Kidney Damage(Cambridge Univ Press, 2023) Tufan, Elif; Sivas, Guezin Goksun; Gurel-Gokmen, Begum; Yilmaz-Karaoglu, Suemeyye; Dursun, Ercan; Caliskan-Ak, Esin; Tunali-Akbay, Tugba; Yllmaz-Karaoǧlu, SÜmeyye; Çallşkan-Ak, EsinMethotrexate (MTX) is a cytotoxic immunosuppressant that is widely used in the treatment of tumours, rheumatoid arthritis and psoriasis. This study aims to evaluate the effects of whey proteins on MTX-induced liver and kidney damage by focusing on oxidant-antioxidant systems and eating habits. The study was conducted in four groups of thirty Sprague-Dawley rats (control, control + whey protein concentrate (WPC), MTX, MTX + WPC). A single dose of 20 mg/kg MTX was administered intraperitoneally to the MTX groups. Control and MTX groups were given 2 g/kg WPC by oral gavage every day for 10 d. At the end of day 10, blood samples were drawn and liver and kidney tissues were removed. MTX administration increased the lipid peroxidation level and decreased glutathione level, superoxide dismutase and glutathione-S-transferase activities in the liver and kidney. Administration of WPC significantly reduced the damage caused by MTX in the liver and kidney. While a decrease in serum urea level and an increase in serum creatinine level were detected in the MTX group, WPC administration reversed these results up to control group levels. Administration of WPC to the MTX group significantly reversed the histopathological damage scores of the liver and kidney. WPC administration ameliorated the MTX-induced oxidative damage in the liver and kidney tissues due to its antioxidant properties. Liver and kidney damage can be prevented by using whey proteins as a nutraceutical in MTX therapy. In conclusion, whey proteins demonstrated a protective effect against MTX-induced liver and kidney damage.Article The Protective Effects of Myrtus Communis Subsp. on Ovariectomized Diabetic Rats’ Renal and Intestinal Tissues: in Vivo and in Silico Approaches(Taylor and Francis Ltd., 2025) Ertik, O.; Kadıoğlu-Yaman, Beril; Şen, Ali; Şener, Göksel; Yanardag, RefiyeIntroduction: Postmenopausal diabetes is a condition that affects millions of women and their quality of life. Also, kidney and small intestine tissues are damaged due to diabetes. The present study aimed to examine the protective effects of an extract prepared from Myrtus communis leaves on kidney and small intestine tissues against experimentally created postmenopausal diabetes. Methods: For this purpose, experimental rats were randomly divided into six groups (Control; ovariectomy:OVX, diabetic:D, ovariectomy + diabetic:OVX + D, ovariectomy + diabetic + oestrogen:OVX + D+E2, ovariectomy + diabetic + MC: OVX + D+MC) and kidney and small intestine tissues were taken after the experimental procedure. Results: Evaluations of biochemical parameters (glutathione and glutathione-related enzymes, antioxidant enzymes, etc.) showed that MC had a protective effect on kidney and small intestine tissues in diabetes and ovariectomy groups. Conclusion: It can be suggested that MC extract has a protective effect on small intestine and kidney tissues in postmenopausal diabetes and may be a good herbal source for this purpose. © 2024 Informa UK Limited, trading as Taylor & Francis Group.
