PubMed İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/397
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Article Citation - WoS: 1Citation - Scopus: 1Targeting Cholinergic Dysfunction and Neuroinflammation through Rationally Designed Thieno[3,2-d]Pyrimidine Hybrids(Academic Press Inc Elsevier Science, 2026-07) Acar, Ozden Ozgun; Acar, Busra; Senol, Halil; Tokali, Feyzi Sinan; Sen, Alaattin; Demir, Yeliz; Cakir, FurkanNeurodegenerative diseases involve the convergence of cholinergic dysfunction, neuronal loss, and sustained neuroinflammatory responses, necessitating the development of multifunctional therapeutic agents. In this study, a series of novel thieno[3,2-d]pyrimidine-phenolic Mannich base hybrids were rationally designed, synthesized, and evaluated as dual cholinesterase inhibitors with neuroprotective and anti-neuroinflammatory potential. The synthesized compounds exhibited potent inhibition against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), with inhibition constants in the low nanomolar range. Among them, compounds 5 and 9 emerged as the most active derivatives, displaying Ki values of 8.79 and 14.11 nM for AChE and 7.04 and 11.75 nM for BChE, surpassing the reference inhibitors tacrine and donepezil. Molecular docking and molecular dynamics simulations supported the experimental findings, and Molecular Mechanics-Generalized Born Surface Area (MM-GBSA) binding free energy calculations further confirmed their superior binding affinities compared with donepezil. Cytotoxicity profiling in SH-SY5Y neuronal cells and RAW 264.7 and THP-1 immune cells identified a narrow sub-cytotoxic concentration window (EC05-EC10 = 1.2-2.1 mu M), ensuring biological effects independent of nonspecific cell damage. Within this range, both compounds exerted pronounced antineuroinflammatory activity. Notably, compound 9 significantly downregulated pro-inflammatory mediators, reducing IL-1 beta, IL-6, and NF-kappa B1 gene expression by up to 2.78-, 3.37-, and 4.84-fold, respectively. Consistently, it suppressed nitric oxide production in LPS-stimulated macrophages to levels comparable with ascorbic acid and markedly decreased Iba1 expression in activated THP-1 cells. This integrated enzymatic, computational, and cellular investigation identifies compounds 5 and 9 as promising multifunctional lead combining dual cholinesterase inhibition with robust anti-neuroinflammatory activity. The results provide a strong foundation for future in vivo studies and further optimization toward disease-modifying agents for neurodegenerative disorders.Article Citation - WoS: 14Citation - Scopus: 15Triterpenoids and Steroids Isolated from Anatolian Capparis Ovata and Their Activity on the Expression of Inflammatory Cytokines(Taylor & Francis Ltd, 2020-01-01) Gazioglu, Isil; Semen, Sevcan; Acar, Ozden Ozgun; Kolak, Ufuk; Sen, Alaattin; Topcu, GulactiContext CapparisL. (Capparaceae) is grown worldwide. Caper has been used in traditional medicine to treat various diseases including rheumatism, kidney, liver, stomach, as well as headache and toothache. Objective To isolate and elucidate of the secondary metabolites of theC. ovataextracts which are responsible for their anti-inflammatory activities. Materials and methods Buds, fruits, flowers, leaves and stems ofC. ovataDesf. was dried, cut to pieces, then ground separately. From their dichloromethane/hexane (1:1) extracts, eight compounds were isolated and their structures were elucidated by NMR, mass spectroscopic techniques. The effects of compounds on the expression of inflammatory cytokines in SH-SY5Y cell lines were examined by qRT-PCR ranging from 4 to 96 mu M. Cell viability was expressed as a percentage of the control, untreated cells. Results This is a first report on isolation of triterpenoids and steroids fromC. ovatawith anti-inflammatory activity. One new triterpenoid ester olean-12-en-3 beta,28-diol, 3 beta-pentacosanoate (1) and two new natural steroids 5 alpha,6 alpha-epoxycholestan-3 beta-ol (5) and 5 beta,6 beta-epoxycholestan-3 beta-ol (6) were elucidated besides known compounds; oleanolic acid (2), ursolic acid (3), beta-sitosterol (4), stigmast-5,22-dien-3 beta-myristate (7) and bismethyl-octylphthalate (8). mRNA expression levels as EC(10)of all the tested seven genes were decreased, particularly CXCL9 (19.36-fold), CXCL10 (8.14-fold), and TNF (18.69) by the treatment of 26 mu M of compound1on SH-SY5Y cells. Discussion and conclusions Triterpenoids and steroids isolated fromC. ovatawere found to be moderate-strong anti-inflammatory compounds. Particularly, compounds1and3were found to be promising therapeutic agents in the treatment of inflammatory and autoimmune diseases.Article Citation - WoS: 6Citation - Scopus: 7Therapeutic Potential of Nitrogen-Substituted Oleanolic Acid Derivatives in Neuroinflammatory and Cytokine Pathways: Insights From Cell-Based and Computational Models(Wiley-VCH Verlag GmbH, 2025-04-22) Turgut, Gurbet Celik; Pepe, Nihan Aktas; Ekiz, Yagmur Ceylan; Senol, Halil; Sen, AlaattinThis study was conducted to investigate the mechanism of the potential and anti-inflammatory properties of nitrogen-substituted oleanolic acid derivatives that can be used to treat neuroinflammatory diseases. Nitrogen-containing oleanolic acid derivatives have been evaluated for their anti-neuroinflammatory effects in vitro in neuronal and monocytic cell lines at nontoxic doses, and the production of cytokines (TNF-alpha, IL-6 and IL-17), the inflammatory enzyme induced nitric oxide synthase (iNOS) and NF-kappa B signalling under LPS-stimulated conditions, and the expression of genes associated with Alzheimer's disease have been assessed. In addition, molecular docking and molecular dynamics simulation assessments are conducted in silico. Key protein markers of neurodegenerative diseases, especially Alzheimer's disease and neuroinflammation, TAU protein levels, and microglial activation, as well as ionised calcium-binding adaptor protein-1 (IBA1) levels, were significantly reduced with the addition of oleanolic acid derivatives. LPS-induced NF-kappa B luciferase reporter activity and iNOS activity were significantly inhibited, approaching the levels in uninduced controls. The mRNA expression of proinflammatory cytokines critical for neuroinflammation, such as TNF-alpha, NF-kappa B, IL-6 and IL-17, was reduced twofold to sevenfold. Furthermore, the molecular docking and MD simulation analyses revealed potential interactions with the TNF-alpha and NF-kappa B proteins. These findings underscore the potential of oleanolic acid derivatives, particularly compound 16, as candidates for further development as therapeutic agents for neurodegenerative diseases associated with chronic inflammation.Article Citation - Scopus: 23Synthesis and Comprehensive in Vivo Activity Profiling of Olean-12-en-28-ol, 3β-Pentacosanoate in Experimental Autoimmune Encephalomyelitis: A Natural Remyelinating and Anti-Inflammatory Agent(American Chemical Society, 2023-01-04) Şenol, Halil; Ozgun-Acar, Özden; Daǧ, Aydan; Eken, Ahmet; Guner, Hüseyin; Aykut, Zaliha Gamze; Sen, AlaattinMultiple sclerosis (MS) treatment has received much attention, yet there is still no certain cure. We herein investigate the therapeutic effect of olean-12-en-28-ol, 3β-pentacosanoate (OPCA) on a preclinical model of MS. First, OPCA was synthesized semisynthetically and characterized. Then, the mice with MOG<inf>35-55</inf>-induced experimental autoimmune/allergic encephalomyelitis (EAE) were given OPCA along with a reference drug (FTY720). Biochemical, cellular, and molecular analyses were performed in serum and brain tissues to measure anti-inflammatory and neuroprotective responses. OPCA treatment protected EAE-induced changes in mouse brains maintaining blood-brain barrier integrity and preventing inflammation. Moreover, the protein and mRNA levels of MS-related genes such as HLD-DR1, CCL5, TNF-α, IL6, and TGFB1 were significantly reduced in OPCA-treated mouse brains. Notably, the expression of genes, including PLP, MBP, and MAG, involved in the development and structure of myelin was significantly elevated in OPCA-treated EAE. Furthermore, therapeutic OPCA effects included a substantial reduction in pro-inflammatory cytokines in the serum of treated EAE animals. Lastly, following OPCA treatment, the promoter regions for most inflammatory regulators were hypermethylated. These data support that OPCA is a valuable and appealing candidate for human MS treatment since OPCA not only normalizes the pro- and anti-inflammatory immunological bias but also stimulates remyelination in EAE. © 2023 Elsevier B.V., All rights reserved.Article Citation - WoS: 22Citation - Scopus: 26Suppression of Inflammatory Cytokines Expression With Bitter Melon (Momordica Charantia) in TNBS-Instigated Ulcerative Colitis(Sciendo, 2020-09-01) Semiz, Asli; Acar, Ozden Ozgun; Cetin, Hulya; Semiz, Gurkan; Sen, AlaattinBackground and Objective: This study was aimed to elucidate the molecular mechanism of Momordica charantia (MCh), along with a standard drug prednisolone, in a rat model of colitis induced by trinitrobenzene sulfonic acid (TNBS). Methods: After the induction of the experimental colitis, the animals were treated with MCh (4 g/kg/day) for 14 consecutive days by intragastric gavage. The colonic tissue expression levels of C-C motif chemokine ligand 17 (CCL-17), interleukin (IL)-1 beta, IL-6, IL-23, interferon-gamma (IFN-gamma), nuclear factor kappa B (NFkB), and tumor necrosis factor-alpha (TNF-alpha), were determined at both mRNA and protein levels to estimate the effect of MCh. Besides, colonic specimens were analyzed histopathologically after staining with hematoxylin and eosin. Results: The body weights from TNBS-instigated colitis rats were found to be significantly lower than untreated animals. Also, the IFN-gamma, IL-1 beta, IL-6, Il-23, TNF-alpha, CCL-17, and NF-kB mRNA and protein levels were increased significantly from 1.86-4.91-fold and 1.46-5.50-fold, respectively, in the TNBS-instigated colitis group as compared to the control. Both the MCh and prednisolone treatment significantly reduced the bodyweight loss. It also restored the induced colonic tissue levels of IL-1 beta, IL-6, IFN-gamma, and TNF-alpha to normal levels seen in untreated animals. These results were also supported with the histochemical staining of the colonic tissues from both control and treated animals. Conclusion: The presented data strongly suggests that MCh has the anti-inflammatory effect that might be modulated through vitamin D metabolism. It is the right candidate for the treatment of UC as an alternative and complementary therapeutics.Article Role of Long Non-Coding RNA X-Inactive Transcript (XIST) in Neuroinflammation and Myelination: Insights From Cerebral Organoids and Implications for Multiple Sclerosis(MDPI, 2025-04-29) Pepe, Nihan Aktas; Acar, Busra; Zararsiz, Gozde Erturk; Guner, Serife Ayaz; Sen, Alaattin; Erturk Zararsiz, Gozde; Ayaz Guner, Serife; Aktas Pepe, NihanBackground/Objectives: X-inactive-specific transcript (XIST) is a factor that plays a role in neuroinflammation. This study investigated the role of XIST in neuronal development, neuroinflammation, myelination, and therapeutic responses within cerebral organoids in the context of Multiple Sclerosis (MS) pathogenesis. Methods: Human cerebral organoids with oligodendrocytes were produced from XIST-silenced H9 cells, and the mature organoids were subsequently treated with either FTY720 or DMF. Gene expression related to inflammation and myelination was subsequently analyzed via qRT-PCR. Immunofluorescence staining was used to assess the expression of proteins related to inflammation, myelination, and neuronal differentiation. Alpha-synuclein protein levels were also checked via ELISA. Finally, transcriptome analysis was conducted on the organoid samples. Results: XIST-silenced organoids presented a 2-fold increase in the expression of neuronal stem cells, excitatory neurons, microglia, and mature oligodendrocyte markers. In addition, XIST silencing increased IL-10 mRNA expression by 2-fold and MBP and PLP1 expression by 2.3- and 0.6-fold, respectively. Although XIST silencing tripled IBA1 protein expression, it did not affect organoid MBP expression. FTY720, but not DMF, distinguished MBP and IBA1 expression in XIST-silenced organoids. Furthermore, XIST silencing reduced the concentration of alpha-synuclein from 300 to 100 pg/mL, confirming its anti-inflammatory role. Transcriptomic and gene enrichment analyses revealed that the differentially expressed genes are involved in neural development and immune processes, suggesting the role of XIST in neuroinflammation. The silencing of XIST modified the expression of genes associated with inflammation, myelination, and neuronal growth in cerebral organoids, indicating a potential involvement in the pathogenesis of MS. Conclusions: XIST may contribute to the MS pathogenesis as well as neuroinflammatory diseases such as and Alzheimer's and Parkinson's diseases and may be a promising therapeutic target.Article Citation - WoS: 20Citation - Scopus: 22Role of Cytochrome P450 Polymorphisms and Functions in Development of Ulcerative Colitis(Baishideng Publishing Group inc, 2019-06-21) Sen, Alaattin; Stark, HolgerCytochromes P450s (CYPs) are terminal enzymes in CYP dependent monooxygenases, which constitute a superfamily of enzymes catalysing the metabolism of both endogenous and exogenous substances. One of their main tasks is to facilitate the excretion of these substances and eliminate their toxicities in most phase 1 reactions. Endogenous substrates of CYPs include steroids, bile acids, eicosanoids, cholesterol, vitamin D and neurotransmitters. About 80% of currently used drugs and environmental chemicals comprise exogenous substrates for CYPs. Genetic polymorphisms of CYPs may affect the enzyme functions and have been reported to be associated with various diseases and adverse drug reactions among different populations. In this review, we discuss the role of some critical CYP isoforms (CYP1A1, CYP2D6, CYP2J2, CYP2R1, CYP3A5, CYP3A7, CYP4F3, CYP24A1, CYP26B1 and CYP27B1) in the pathogenesis or aetiology of ulcerative colitis concerning gene polymorphisms. In addition, their significance in metabolism concerning ulcerative colitis in patients is also discussed showing a clear underestimation in genetic studies performed so far.Article Citation - WoS: 16Citation - Scopus: 15Role of AHR, NF-kB and CYP1A1 Crosstalk With the X Protein of Hepatitis B Virus in Hepatocellular Carcinoma Cells(Elsevier, 2023-02) Celik-Turgut, Gurbet; Olmez, Nazmiye; Koc, Tugba; Ozgun-Acar, Ozden; Semiz, Asli; Dodurga, Yavuz; Sen, AlaattinIn this study, it was aimed to elucidate the interaction between aryl hydrocarbon receptor (AHR), nuclear factor -kappa B (NF-kB), and cytochrome P4501A1 (CYP1A1) with hepatitis B virus X protein (HBX) in a human liver cancer cell line (HepG2) transfected with HBX. First, AHR, NF-kB, and CYP1A1 genes were cloned into the appropriate region of the CheckMate mammalian two-hybrid recipient plasmids using a flexi vector system. Renilla and firefly luciferases were quantified using the dual-luciferase reporter assay system to measure the interactions. Secondly, transient transfections of CYP1A1 and NF-kB (RelA) were performed into HBX-positive and HBX-negative HepG2 cells. The mRNA expression of CYP1A1 and NF-kB genes were confirmed with RT-PCR, and cell viability was measured by WST-1. Further verification was assessed by measuring the activity and protein level of CYP1A1. Additionally, CYP1A1/HBX protein-protein interactions were performed with co-immunoprecipitation, which demonstrated no interaction. These results have clearly shown that the NF-kB and AHR genes interact with HBX without involving CYP1A1 and HBX protein-protein interactions. The present study confirms that AHR and NF-kB interaction plays a role in the HBV mechanism mediated via HBX and coordinating the carcinogenic or inflammatory responses; still, the CYP1A1 gene has no effect on this interaction.Article Citation - WoS: 70Citation - Scopus: 78Prophylactic and Therapeutic Roles of Oleanolic Acid and Its Derivatives in Several Diseases(Baishideng Publishing Group inc, 2020-05-26) Sen, AlaattinOleanolic acid (OA) and its derivatives are widely found in diverse plants and are naturally effective pentacyclic triterpenoid compounds with broad prophylactic and therapeutic roles in various diseases such as ulcerative colitis, multiple sclerosis, metabolic disorders, diabetes, hepatitis and different cancers. This review assembles and presents the latestin vivoreports on the impacts of OA and OA derivatives from various plant sources and the biological mechanisms of OA activities. Thus, this review presents sufficient data proposing that OA and its derivatives are potential alternative and complementary therapies for the treatment and management of several diseases.Article Citation - Scopus: 1Possible Drug-Drug Interactions Between Mesalamine and Tricyclic Antidepressants Through CYP2D6 Metabolism - in Silico and in Vitro Analyses(Georg Thieme Verlag, 2025-04-01) Ozen, Melek B.; Gazioğlu, Işil; Ozgun-Acar, Özden; Guner, Hüseyin; Semiz, Gürkan; Sen, Alaattin; Ozgun Acar, OzdenMesalamine (mesalazine, 5-aminosalicylic acid, 5-ASA) is an essential anti-inflammatory agent both used for therapy and as a remission control in patients with inflammatory bowel diseases (IBD) such as ulcerative colitis (UC). Tricyclic antidepressants (TCAs) are used to alleviate remaining symptoms in patients already receiving IBD therapy or with quiescent inflammation. The cytochrome P4502D6 enzyme is involved in the metabolism of TCAs. Hence, it is crucial to investigate the role of CYP2D6 in 5-ASA metabolism. Initially, in silico analysis involving the docking of 5-ASA to CYP2D6 and molecular dynamics simulations was conducted. Next, the rate of O-demethylation of a nonfluorescent probe 3-[2-(N,N-diethyl-N-methylammonium)-ethyl]-7-methoxy-4-methylcoumarin (AMMC) into a fluorescent metabolite AMHC (3-[2-(N,N-diethyl-N-methylammonium)ethyl]-7-hydroxy-4-methylcoumarin) was optimized with baculosomes co-expressing human CYP2D6 and human P450 oxidoreductase (hCPR) to monitor CYP2D6 activity in a microtiter plate assay. The apparent Km and Vmax were found to be 1.30 μM and 32.68 pmol/min/mg of protein for the O-demethylation of AMMC to AMHC, and the reaction was linear for 40 min. Then, nonselective inhibition of CYP2D6 activity with various concentrations of 5-ASA was detected. Finally, the conversion of AMMC to metabolites was analyzed by HPLC-ESI-MS/MS spectrometry, and none were identified. Thus, this study suggests that concurrent use of mesalamine with TCA may lead to adverse effects, and CYP2D6 genotyping should be routinely performed on these patients to eliminate possible threats. © 2025 Elsevier B.V., All rights reserved.