PubMed İndeksli Yayınlar Koleksiyonu

Permanent URI for this collectionhttps://hdl.handle.net/20.500.14627/8

Browse

Filters

2025 - 20265

Settings

Start date: 2025Subject: search.filters.subject.Oxidative Stress

Search Results

Now showing 1 - 5 of 5
  • 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 Oguzhan
    Methotrexate (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 Oguzhan
    Background 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, Özge
    BackgroundChronic 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 Ercalik
    Prenatal 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 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, Refiye
    Introduction: 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.