10 research outputs found
Biopiracy <i>versus </i>one-world medicine – from colonial relicts to global collaborative concepts
Background: Practices of biopiracy to use genetic resources and indigenous knowledge by Western companies without benefit-sharing of those, who generated the traditional knowledge, can be understood as form of neocolonialism.Hypothesis: : The One-World Medicine concept attempts to merge the best of traditional medicine from developing countries and conventional Western medicine for the sake of patients around the globe.Study design: Based on literature searches in several databases, a concept paper has been written. Legislative initiatives of the United Nations culminated in the Nagoya protocol aim to protect traditional knowledge and regulate benefit-sharing with indigenous communities. The European community adopted the Nagoya protocol, and the corresponding regulations will be implemented into national legislation among the member states. Despite pleasing progress, infrastructural problems of the health care systems in developing countries still remain. Current approaches to secure primary health care offer only fragmentary solutions at best. Conventional medicine from industrialized countries cannot be afforded by the impoverished population in the Third World. Confronted with exploding costs, even health systems in Western countries are endangered to burst. Complementary and alternative medicine (CAM) is popular among the general public in industrialized countries, although the efficacy is not sufficiently proven according to the standards of evidence-based medicine. CAM is often available without prescription as over-the-counter products with non-calculated risks concerning erroneous self-medication and safety/toxicity issues. The concept of integrative medicine attempts to combine holistic CAM approaches with evidence-based principles of conventional medicine.Conclusion: To realize the concept of One-World Medicine, a number of standards have to be set to assure safety, efficacy and applicability of traditional medicine, e.g. sustainable production and quality control of herbal products, performance of placebo-controlled, double-blind, randomized clinical trials, phytovigilance, as well as education of health professionals and patients
Isolatıon of Potentıal Drug Candıdate Molecules from Rumex Acetosella L. and in Sılıco, in Vıtro Researches on Those Molecules
Ozenver, N., Isolation of Potential Drug Candidate Molecules From Rumex acetosella L. and In Silico, In Vitro Researches on Those Molecules, Hacettepe University, Institute of Health Sciences, Pharmacognosy Program, Doctor of Philosophy Thesis, Ankara, 2018. In this thesis, biological activity studies on the extracts of R. acetosella as well as its compounds were conducted. Some extracts of the title plant and some isolated substances were investigated against diabetes and cancer, hence R. acetosella is traditionally used in diabetes and cancer. Initially, antioxidant studies were performed as preliminary researches so that oxidative stress may have a role in the etiology of these diseases, which indicated alcoholic extracts as good antioxidants. Then, isolation studies were conducted to view phytochemical profile of R. acetosella. Isolated compounds and the main anthraquinone aglycones were tested for their cytotoxicities by resazurin reduction and protease viability marker assays. Aloe-emodin was detected as the most cytotoxic compound and the mechanisms behind its cytotoxicity were further investigated. Inducement of cell cycle distribution, apoptosis and necrosis, reactive oxygen species, mitochondrial membrane potential breakdown, DNA damage were detected. Microarray hybridization revealed deregulated genes in aloe-emodin-treated cells, validating by qPCR analysis. Motif analysis pointed out NF-κB as a transcriptional regulator. Molecular docking and reporter cell assays revealed the aloe-emodin/NF-κB relation. Antidiabetic effects of the extracts and some of their chemical constituents were investigated by means of α-amylase and α-glucosidase inhibition assays, which emphasized the ethanol extracts as antidiabetic, confirming the traditional use of R. acetosella. All findings pointed out that R. acetosella and aloe-emodin may have potentials for the development of new drugs in the treatment of both diabetes and cancer.
Key Words: Rumex acetosella, aloe-emodin, cancer, diabetes, phytochemistry.
Acknowledgments: The studies in this thesis were supported by The Scientific and Technological Research Council of Turkey (TÜBİTAK) with 2214-A and 2211-C scholarship programmes as well as Hacettepe University Scientific Research Projects Coordination Unit (Project No: 1216, TED-2017-15246).Özenver, N., Rumex acetosella L. Bitkisinden Potansiyel İlaç Adayı Moleküllerin İzolasyonu ve Moleküller Üzerinde İn Siliko, İn Vitro Araştırmalar, Hacettepe Üniversitesi Sağlık Bilimleri Enstitüsü Farmakognozi Programı, Doktora Tezi, Ankara, 2018. Bu tezde R. acetosella ekstreleri ve içerdiği maddeler üzerinde biyolojik aktivite çalışmaları gerçekleştirilmiştir. R. acetosella’nın geleneksel olarak diyabet ve kansere karşı kullanılması nedeniyle bitkiden hazırlanan bazı ekstreler ve bunardan izole edilen bazı maddelerin antidiyabetik ve sitotoksik etkileri araştırılmıştır. Oksidatif stresin bu hastalıkların etiyolojisinde rol alması nedeniyle, başlangıçta ön araştırma olarak antioksidan çalışmalar yapılmış ve etanollü ekstrelerin en iyi antioksidanlar olduğu görülmüştür. Daha sonra, R. acetosella’nın fitokimyasal profilini belirlemek için izolasyon çalışmaları yürütülmüştür. İzole edilen maddelerin ve temel antrakinon aglikonlarının sitotoksisiteleri “resazurin redüksiyon” ve “proteaz viability marker” yöntemleri ile araştırılmıştır. Aloe-emodin en yüksek sitotoksik etkiyi göstermiş ve sitotoksisitesinin altında yatan mekanizmalar da ayrıca araştırılmıştır. Hücre döngüsünün bozulmasının, apoptozun, nekrozun, reaktif oksijen türlerinin, mitokondri zar potansiyelinin bozulmasının ve DNA zararının indüklendiği görülmüştür. Mikrodizi hibridizasyonu, aloe-emodin ile muamele edilen CCRF-CEM hücrelerinde düzensiz gen profillerini ortaya çıkarmış ve qPCR analizi ile doğrulanmıştır. Motif analizi ile NF-κB transkripsiyonal bir düzenleyici olarak gösterilmiştir. Moleküler doking ve “reporter hücre” yöntemleri ile aloe-emodin/NF-κB ilişkisi gösterilmiştir. Ekstreler ve antrakinon aglikonlarının antidiyabetik etkileri, α-amilaz ve α-glukozidaz inhibisyonu yöntemleri ile araştırılmış; etanollü ekstrelerin R. acetosella’nın geleneksel kullanımını doğrulayacak şekilde antidiyabetik etkili olabileceği gösterilmiştir. Tüm bulgular, R. acetosella ve aloe-emodinin diyabet ve kanserde yeni ilaçların geliştirilmesinde potansiyel olabileceklerini göstermiştir.
Anahtar Kelimeler: Rumex acetosella, aloe-emodin, kanser, diyabet, fitokimya.
Teşekkür: Bu tezde yer alan çalışmalar, TÜBİTAK 2214-A ve 2211-C burs programları ve Hacettepe Üniversitesi Bilimsel Araştırma Projeleri Koordinasyon Birimi (Proje No: 1216, TED-2017-15246) tarafından desteklenmiştir
Identification of Prognostic and Predictive Biomarkers and Druggable Targets among 205 Antioxidant Genes in 21 Different Tumor Types via Data-Mining
(1) Background: Oxidative stress is crucial in carcinogenesis and the response of tumors to treatment. Antioxidant genes are important determinants of resistance to chemotherapy and radiotherapy. We hypothesized that genes involved in the oxidative stress response may be valuable as prognostic biomarkers for the survival of cancer patients and as druggable targets. (2) Methods: We mined the KM Plotter and TCGA Timer2.0 Cistrome databases and investigated 205 antioxidant genes in 21 different tumor types within the context of this investigation. (3) Results: Of 4347 calculations with Kaplan–Meier statistics, 84 revealed statistically significant correlations between high gene expression and worse overall survival (p p ALOX5, ALOX5AP, EPHX4, G6PD, GLRX3, GSS, PDIA4, PDIA6, PRDX1, SELENOH, SELENON, STIP1, TXNDC9, TXNDC12, TXNL1, TXNL4A, and TXNRD1). (4) Conclusions: We concluded that a sub-set of antioxidant genes might serve as prognostic biomarkers for overall survival and as druggable targets. Renal and liver tumors may be the most suitable entities for this approach
Kinome-Wide Profiling Identifies Human WNK3 as a Target of Cajanin Stilbene Acid from Cajanus cajan (L.) Millsp.
Pigeon Pea (Cajanus cajan (L.) Millsp.) is a common food crop used in many parts of the world for nutritional purposes. One of its chemical constituents is cajanin stilbene acid (CSA), which exerts anticancer activity in vitro and in vivo. In an effort to identify molecular targets of CSA, we performed a kinome-wide approach based on the measurement of the enzymatic activities of 252 human kinases. The serine-threonine kinase WNK3 (also known as protein kinase lysine-deficient 3) was identified as the most promising target of CSA with the strongest enzymatic activity inhibition in vitro and the highest binding affinity in molecular docking in silico. The lowest binding affinity and the predicted binding constant pKi of CSA (−9.65 kcal/mol and 0.084 µM) were comparable or even better than those of the known WNK3 inhibitor PP-121 (−9.42 kcal/mol and 0.123 µM). The statistically significant association between WNK3 mRNA expression and cellular responsiveness to several clinically established anticancer drugs in a panel of 60 tumor cell lines and the prognostic value of WNK3 mRNA expression in sarcoma biopsies for the survival time of 230 patients can be taken as clues that CSA-based inhibition of WNK3 may improve treatment outcomes of cancer patients and that CSA may serve as a valuable supplement to the currently used combination therapy protocols in oncology
Aloe-Emodin As Drug Candidate For Cancer Therapy
As a leading cause of global mortality, cancer frequently cannot be cured due to the development of drug resistance. Therefore, novel drugs are required. Naturally occurring anthraquinones are mostly present in Rumex and Rhamnus species and are of interest because of their structural similarity to anthracyclines as well established anticancer drugs. In the present study, we focused on the structural elucidation of phytochemicals from R. acetosella as well as the investigation of cytotoxicity and modes of action of the main anthraquinone aglycons (emodin, Aloe-emodin, physcion, rhein). Resazurin reduction and protease viability marker assays were conducted to test their cytotoxicity. Microarray-based gene expression profiling was performed to identify cellular pathways affected by the compounds, which was validated by qPCR analyses and functional assays. Flow cytometry was used to measure cell cycle distribution, apoptosis and necrosis, induction of reactive oxygen species (ROS) and disruption of mitochondrial membrane potential (MMP). The comet assay was used to detect DNA damage. Aloe-emodin as the most cytotoxic compound revealed IC50 values from 9.872 μM to 22.3 μM in drug-sensitive wild-type cell lines and from 11.19 μM to 33.76 μM in drug-resistant sublines, was selected to investigate its mechanism against cancer. Aloe-emodin-induced S phase arrest, ROS generation, DNA damage and apoptosis. Microarray hybridization revealed a profile of deregulated genes in Aloe-emodin-treated CCRF-CEM cells with diverse functions such as cell death and survival, cellular growth and proliferation, cellular development, gene expression, cellular function and maintenance. Aloe-emodin as well as R. acetosella deserve further investigations as possible antineoplastic drug candidates.PubMedScopu
Chemometric and Transcriptomic Profiling, Microtubule Disruption and Cell Death Induction by Secalonic Acid in Tumor Cells
Nature is an indispensable source of new drugs, providing unique bioactive lead structures for drug discovery. In the present study, secalonic acid F (SAF), a naturally occurring ergochrome pigment, was studied for its cytotoxicity against various leukemia and multiple myeloma cells by the resazurin assay. SAF exhibited cytotoxic activity on both leukemia and multiple myeloma cells. Generally, multiple myeloma cells were more sensitive to SAF than leukemia cells. NCI-H929 cells were the most affected cells among the tested panel of multiple myeloma cell lines and were taken for further studies to assess the mode of action of SAF on those cells. Cell cycle analysis revealed that SAF induced S and G2/M arrest in NCI-H929 cells. SAF-associated apoptosis and necrosis resulted in cytotoxicity. SAF further inclined the disassembly of the tubulin network, which may also account for its cytotoxicity. COMPARE and hierarchical cluster analyses of transcriptome-wide expression profiles of the NCI tumor cell line panel identified genes involved in numerous cellular processes (e.g., cell differentiation, cell migration, and other numerous signaling pathways) notably correlated with log10IC50 values for secalonic acid. In conclusion, the present study supports the therapeutic potential of SAF to treat multiple myeloma
Identification and characterization of deschloro-chlorothricin obtained from a large natural product library targeting aurora A kinase in multiple myeloma
Multiple myeloma (MM) is a devastating disease with low survival rates worldwide. The mean lifetime of patients may be extendable with new drug alternatives. Aurora A kinase (AURKA) is crucial in oncogenesis, because its overexpression or amplification may incline the development of various types of cancer, including MM. Therefore, inhibitors of AURKA are innovative and promising targets. Natural compounds always represented a valuable resource for anticancer drug development. In the present study, based on virtual drug screening of more than 48,000 natural compounds, the antibiotic deschloro-chlorotricin (DCCT) has been identified to bind to AURKA with even higher binding affinity (free bindung energy: -12.25 kcal/mol) than the known AURKA inhibitor, alisertib (free binding energy: -11.25 kcal/mol). The in silico studies have been verified in vitro by using microscale thermophoresis. DCCT inhibited MM cell lines (KMS-11, L-363, RPMI-8226, MOLP-8, OPM-2, NCI-H929) with I
Molecular docking and ex vivo and in vitro anticholinesterase activity studies of Salvia sp and highlighted rosmarinic acid
Background/aim: To evaluate acetylcholinesterase (AChE) inhibitory activity and antioxidant capacity of the major molecule from Salvia sp., rosmarinic acid, as a drug candidate molecule for treatment of Alzheimer disease (AD)
Molecular Modes of Action of an Aqueous <i>Nerium oleander</i> Extract in Cancer Cells In Vitro and In Vivo
Cancer drug resistance remains a major obstacle in clinical oncology. As most anticancer drugs are of natural origin, we investigated the anticancer potential of a standardized cold-water leaf extract from Nerium oleander L., termed Breastin. The phytochemical characterization by nuclear magnetic resonance spectroscopy (NMR) and low- and high-resolution mass spectrometry revealed several monoglycosidic cardenolides as major constituents (adynerin, neritaloside, odoroside A, odoroside H, oleandrin, and vanderoside). Breastin inhibited the growth of 14 cell lines from hematopoietic tumors and 5 of 6 carcinomas. Remarkably, the cellular responsiveness of odoroside H and neritaloside was not correlated with all other classical drug resistance mechanisms, i.e., ATP-binding cassette transporters (ABCB1, ABCB5, ABCC1, ABCG2), oncogenes (EGFR, RAS), tumor suppressors (TP53, WT1), and others (GSTP1, HSP90, proliferation rate), in 59 tumor cell lines of the National Cancer Institute (NCI, USA), indicating that Breastin may indeed bypass drug resistance. COMPARE analyses with 153 anticancer agents in 74 tumor cell lines of the Oncotest panel revealed frequent correlations of Breastin with mitosis-inhibiting drugs. Using tubulin-GFP-transfected U2OS cells and confocal microscopy, it was found that the microtubule-disturbing effect of Breastin was comparable to that of the tubulin-depolymerizing drug paclitaxel. This result was verified by a tubulin polymerization assay in vitro and molecular docking in silico. Proteome profiling of 3171 proteins in the NCI panel revealed protein subsets whose expression significantly correlated with cellular responsiveness to odoroside H and neritaloside, indicating that protein expression profiles can be identified to predict the sensitivity or resistance of tumor cells to Breastin constituents. Breastin moderately inhibited breast cancer xenograft tumors in vivo. Remarkably, in contrast to what was observed with paclitaxel monotherapy, the combination of paclitaxel and Breastin prevented tumor relapse, indicating Breastin’s potential for drug combination regimens