78 results on '"Kallay E"'
Search Results
2. The evaluation of therapeutic horticulture effects on urinary tryptophan metabolites by using the spectrofluorimetric analysis in a group of students
- Author
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Buru, T., primary, Kallay, E., additional, Olar, L.E., additional, Stefan, R., additional, Buta, E., additional, Cantor, M., additional, and Papuc, I., additional
- Published
- 2019
- Full Text
- View/download PDF
3. The effect of vitamin D on the expression of the calcium-sensing receptor in colonic organoids
- Author
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Iamartino, L., Barbáchano, Antonio, Muñoz Terol, Alberto, Kallay, E., Iamartino, L., Barbáchano, Antonio, Muñoz Terol, Alberto, and Kallay, E.
- Abstract
The calcium-sensing receptor (CaSR) is a heterotrimeric G protein-coupled receptor that regulates Ca2+ homeostasis in the blood. lt is suggested that the CaSR, in synergism with vitamin O, controls proliferation, differentiation and apoptosis of intestinal cells, and protects intestinal integrity preventing the development of colorectal cancer. However, the CaSR is down-regulated during tumorigenesis. We hypothesized that CaSR expression is linked to differentiation, and substances inducing differentiation, like vitamin O, would restare its expression. Therefore, we tested whether inducing differentiation of murine colonic organoids and treating them with 1 ,25-dihydroxyvitamin 03 (1 ,25-03) will re-establish CaSR expression. We have shown previously that vitamin O was able to induce CaSR expression in vivo, in normal colonic mucosa of m ice. In the present study we used a 30 in vitro culture system, by generating normal organoids from murine colonic crypts. We induced lineage-specific differentiation of the organoids either into enterocytes or goblet cells by altering the composition of the culturing media in combination with 100 nM 1,25-03. We assessed CaSR expression by RT-qPCR and immunofluorescence assays, testing also specific differentiation markers such as FABP2 for enterocytes and MUC2 for goblet cells. Our data showed that the CaSR was not expressed in the undifferentiated organoids cultured in stem cell media, where even the differentiation markers were barely detectable. 1,25-03 enhanced CaSR expression in organoids differentiated towards enterocytes, while in goblet cell-like condition CaSR expression remained undetectable. Our results not showed that CaSR is preferentially expressed in differentiated enterocytes and also that 1 ,25-03 further enhanced its expression. We conclude that 1 ,25-03 is not able to induce CaSR expression in undifferentiated colonic stem cells. However, 1 ,25-03 enhances CaSR expression during enterocyte-specific differentiatio
- Published
- 2018
4. Mutant mice with calcium-sensing receptor (CaSR) activation have hyperglycemia, that is rectified by calcilytic therapy
- Author
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Babinsky, V, Hannan, F, Ramracheya, R, Zhang, F, Nesbit, M, Hugill, A, Bentley, L, Hough, T, Joynson, E, Stewart, M, Aggarwal, A, Prinz-Wohlgenannt, M, Gorvin, C, Kallay, E, Wells, S, Cox, R, Richards, D, Rorsman, P, and Thakker, R
- Subjects
endocrine system - Abstract
The calcium-sensing receptor (CaSR) is a family C G-protein-coupled receptor (GPCR) that plays a pivotal role in extracellular calcium homeostasis. The CaSR is also highly expressed in pancreatic islet α- and β-cells that secrete glucagon and insulin, respectively. To determine whether the CaSR may influence systemic glucose homeostasis, we characterized a mouse model with a germline gain-of-function CaSR mutation, Leu723Gln, referred to as Nuclear flecks (Nuf). Heterozygous- (CasrNuf/+) and homozygous-affected (CasrNuf/Nuf) mice were shown to have hypocalcemia in association with impaired glucose tolerance and insulin secretion. Oral administration of a CaSR antagonist compound, known as a calcilytic, rectified the glucose intolerance and hypoinsulinemia of CasrNuf/+ mice, and ameliorated glucose intolerance in CasrNuf/Nuf mice. Ex vivo studies showed CasrNuf/+ and CasrNuf/Nuf mice to have reduced pancreatic islet mass and β-cell proliferation. Electrophysiological analysis of isolated CasrNuf/Nuf islets showed CaSR activation to increase the basal electrical activity of β-cells independently of effects on the activity of the ATP-sensitive K+ (KATP) channel. CasrNuf/Nuf mice also had impaired glucose-mediated suppression of glucagon secretion, which was associated with increased numbers of α-cells and a higher α-cell proliferation rate. Moreover, CasrNuf/Nuf islet electrophysiology demonstrated an impairment of α-cell membrane depolarization in association with attenuated α-cell basal KATP channel activity. These studies indicate that the CaSR activation impairs glucose tolerance by a combination of α- and β-cell defects and also influences pancreatic islet mass. Moreover, our findings highlight a potential application of targeted CaSR compounds for modulating glucose metabolism.
- Published
- 2017
5. Expression profiling of colorectal cancer cells reveals inhibition of DNA replication licensing by extracellular calcium
- Author
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Aggarwal, A, Schulz, H, Manhardt, T, Bilban, M, Thakker, R, and Kallay, E
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Cell Biology ,Molecular Biology - Abstract
Colorectal cancer is one of the most common cancers in industrialised societies. Epidemiological studies, animal experiments, and randomized clinical trials have shown that dietary factors can influence all stages of colorectal carcinogenesis, from initiation through promotion to progression. Calcium is one of the factors with a chemoprophylactic effect in colorectal cancer. The aim of this study was to understand the molecular mechanisms of the anti-tumorigenic effects of extracellular calcium ([Ca2+]o) in colon cancer cells. Gene expression microarray analysis of colon cancer cells treated for 1, 4, and 24 h with 2 mM [Ca2+]o identified significant changes in expression of 1571 probe sets (ANOVA, p < 10− 5). The main biological processes affected by [Ca2+]o were DNA replication, cell division, and regulation of transcription. All factors involved in DNA replication-licensing were significantly downregulated by [Ca2+]o. Furthermore, we show that the calcium-sensing receptor (CaSR), a G protein-coupled receptor is a mediator involved in this process. To test whether these results were physiologically relevant, we fed mice with a standard diet containing low (0.04%), intermediate (0.1%), or high (0.9%) levels of dietary calcium. The main molecules regulating replication licensing were inhibited also in vivo, in the colon of mice fed high calcium diet. We show that among the mechanisms behind the chemopreventive effect of [Ca2+]o is inhibition of replication licensing, a process often deregulated in neoplastic transformation. Our data suggest that dietary calcium is effective in preventing replicative stress, one of the main drivers of cancer and this process is mediated by the calcium-sensing receptor.
- Published
- 2017
6. PO-118 The expression of the calcium-sensing receptor in colon organoids
- Author
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Iamartino, L., primary, Barbáchano, A., additional, Muñoz, A., additional, and Kallay, E., additional
- Published
- 2018
- Full Text
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7. Correlates of Fear of Cancer Progression during COVID-19 in Romania
- Author
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Flavia Medrea, Kállay Éva, and Dégi László Csaba
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fear of cancer progression ,romania ,covid-19 ,anxiety ,illness intrusiveness ,Medicine ,Medicine (General) ,R5-920 - Abstract
Objectives. Fear of cancer progression (FoP) is one of patients’ greatest concerns and one of the most reported unmet needs. Higher levels of FoP can negatively impact a patient’s quality of life, impairing physical, emotional, social and functional well-being. The Romanian health-care system has difficulties in offering qualitative psychosocial assistance for cancer outpatients. Due to their specific implications, the COVID-19 pandemic restrictions might further affect FoP, therefore our objective was to investigate correlates of FoP in cancer outpatients during the COVID-19 pandemic in Romania. Material and methods. The study investigated correlates of FoP in 330 Romanian cancer outpatients assessed during 2021. T-tests, Multivariate General Linear Models and Hierarchical Regression Models were conducted in order to assess the relationship between variables. Outcomes. Results showed differences in the assessed variables depending on gender (women had scores significantly higher than men regarding FoP and illness intrusiveness) and marital status. Moreover, using a hierarchical regression model, we identified three statistically significant predictors of FoP: gender, illness intrusiveness regarding relationships and anxiety, together explaining 38.2% of the variance in global FoP scores. Anxiety was the most important predictor of FoP, explaining 21.3% of the variance in the FoP scores, 5 times more than gender and almost 2 times more than illness intrusiveness in interpersonal relationships. Conclusions. Cancer is a complex experience, impacted by both socio-demographic variables such as gender and marital status, as well as psychological variables such as anxiety and fear of disease progression. Individualized psychosocial-care should be recognized as essential, and personalized interventions should be integrated into the patient's treatment plan.
- Published
- 2022
- Full Text
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8. Ein Hormon stellt sich vor: Der Calcium-sensing Rezeptor
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Kallay E
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lcsh:RC648-665 ,lcsh:Diseases of the endocrine glands. Clinical endocrinology - Published
- 2012
9. 480: Calcium sensing receptor mediated downstream signalling in colonocytes
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Tennakoon, S., primary, Aggarwal, A., additional, Hegedus, L., additional, Wohlgenannt, M., additional, and Kallay, E., additional
- Published
- 2014
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10. 592 Are Epigenetic Mechanisms Responsible for Silencing the Calcium Sensing Receptor in Colorectal Cancer?
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Fetahu, I.S., primary, Hobaus, J., additional, Hummel, D., additional, Thiem, U., additional, Manhardt, T., additional, and Kallay, E., additional
- Published
- 2012
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11. CYP24A1 splice variants—Implications for the antitumorigenic actions of 1,25-(OH)2D3 in colorectal cancer
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Horváth, H.C., primary, Khabir, Z., additional, Nittke, T., additional, Gruber, S., additional, Speer, G., additional, Manhardt, T., additional, Bonner, E., additional, and Kallay, E., additional
- Published
- 2010
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12. 416 Characterization and quantification of macrophages in colorectal cancer by an automated cell system
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Rogojanu, R., primary, Mesteri, I., additional, Ellinger, I., additional, Talhammer, T., additional, Kallay, E., additional, Heindl, A., additional, Seewald, A., additional, and Bises, G., additional
- Published
- 2010
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13. Pathways involved in the antiproliferative effect of calcium in colon cancer cells
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Kallay⁎, E., primary
- Published
- 2009
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14. The role of Foxp3+ T cells in long-term efficacy of prophylactic and therapeutic mucosal tolerance induction in mice.
- Author
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Winkler, B., primary, Hufnagl, K., additional, Spittler, A., additional, Ploder, M., additional, Kallay, E., additional, Vrtala, S., additional, Valenta, R., additional, Kundi, M., additional, Renz, H., additional, and Wiedermann, U., additional
- Published
- 2006
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15. Cross-cultural approaches to studying the effects of expressive writing
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Manier, D., primary, Coman, A., additional, Rotaru, D., additional, Opre, A., additional, Esbitt, S., additional, Anton, R., additional, and Kallay, E., additional
- Published
- 2005
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16. Characterization of a vitamin D receptor knockout mouse as a model of colorectal hyperproliferation and DNA damage
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Kallay, E., primary
- Published
- 2001
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17. Involvement of epigenetic mechanisms in regulating expression of the calcium sensing receptor in colorectal cancer
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Fetahu, I.Sh., Höbaus, J., Gröschel, C., Tennakoon, S., Manhardt, T., Mesteri, I., Baumgartner-Parzer, S., and Kállay, E.
- Published
- 2012
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18. Regulation of signalling pathways by extracellular calcium in colon cancer cells
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Tennakoon, S., Marian, B., Schmid, J., and Kállay, E.
- Published
- 2012
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19. The role of serine/threonine protein kinases in regulating expression of the vitamin D metabolizing enzyme CYP24A1 in colon cancer
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Gröschel, C., Hummel, D., Nittke, T., Manhardt, T., and Kállay, E.
- Published
- 2012
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20. High dietary vitamin D can prevent chemically-induced colorectal tumorigenesis in mice
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Hummel, D.M., Thiem, U., Fetahu, I.Sh., Höbaus, J., Gober, L., Hacker, N., Graca, J., Mesteri, I., and Kállay, E.
- Published
- 2012
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21. Overexpression of the vitamin D degrading enzyme CYP24A1 in highly proliferative tumors
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Höbaus, J., Fetahu, I.Sh., Aggarwal, A., Hummel, D.M., Mesteri, I., and Kállay, E.
- Published
- 2012
- Full Text
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22. Growth regulation of human colon cancer cells by epidermal growth factor and 1,25-dihydroxyvitamin D~3 is mediated by mutual modulation of receptor expression
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Tong, W.-M., Kallay, E., Hofer, H., Hulla, W., Manhardt, T., Peterlik, M., and Cross, H. S.
- Published
- 1998
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23. Nutritional Soy Rescues the Mouse Colon from Hyperproliferation and Supports Colonic Vitamin D Synthesis.
- Author
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Cross, H.S., Kallay, E., Bajna, E., and Lechner, D.
- Subjects
- *
VITAMIN D , *CANCER & nutrition , *NUTRITION - Abstract
Epidemiologic studies have suggested a beneficial effect of sunshine against colorectal cancer incidence. Cholecalciferol (vitamin D[sub 3]) is produced in the skin by UV energy. The active hormonal metabolite 1,25-dihydroxyvitamin D[sub 3] (1,25-D) is known to be antimitotic and prodifferentiating in cancer cells. We were the first to demonstrate presence of 1,25-D synthesizing (CYP27B1) and degrading (CYP24) enzymes as well as of the vitamin D receptor (VDR) in human colon cancer cells and tissues. Interestingly, expression of enzymes and of the steroid hormone receptor at the mRNA and protein level is upregulated early during tumor progression whereas expression in late-stage high-grade tumors is diminished. Our studies in VDR knockout mice have demonstrated that the lack of genomic action of 1,25-D via VDR would result in enhanced proliferation and in DNA lesions. Such data suggest that the vitamin D system may be a physiological defense against tumor progression, losing its efficacy during late-stage malignancy. Proper functioning of this defense would necessitate high levels of 1,25-D synthesizing enzymes and low levels of catabolic enzymes in the colon. We were able to demonstrate in a mouse model that soy feeding or genistein gavage results in enhanced expression of CYP27B1 and reduced expression of CYP24. When mice were fed a low-calcium diet (0.04% vs. 0.9% of normal calcium levels), expression of CYP24 mRNA was increased at least 14-fold in parallel to enhanced proliferation of the colon mucosa, whereas mice on the low-calcium diet fed with 10% soy showed a reduction of CYP24 mRNA expression to normal low levels. Our data demonstrate that the raised catabolism of 1,25-D occurring during increased proliferation of the colon mucosa can be counteracted by soy nutrition. Decreased catabolism would result in the enhanced presence of the steroid hormone in tissues. This in turn could support normal colonic growth and could inhibit tumor progression. [Supported by the World Cancer Research Fund, London, UK. [ABSTRACT FROM AUTHOR]
- Published
- 2003
24. CYP24A1 splice variants—Implications for the antitumorigenic actions of 1,25-(OH)2D3 in colorectal cancer
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Horváth, H.C., Khabir, Z., Nittke, T., Gruber, S., Speer, G., Manhardt, T., Bonner, E., and Kallay, E.
- Subjects
- *
COLON cancer , *ANTINEOPLASTIC agents , *CHOLECALCIFEROL , *CYTOCHROME P-450 , *GENETIC engineering , *CANCER cells , *MITOCHONDRIA - Abstract
Abstract: 25-Hydroxyvitamin D3 24-hydroxylase (CYP24A1), the catabolizing enzyme of the active vitamin D3, is often overexpressed in solid tumors. The unbalanced high levels of CYP24A1 seem to be a determinant of vitamin D resistance in tumors. Splice variants of CYP450 enzymes are common. Existence of CYP24A1 isoforms has been reported recently. We have investigated the presence of CYP24A1 splicing variants (SV) in human colon cancer cell lines and tissue samples. Using a set of primer combination we have screened the entire coding sequence of CYP24A1 and identified three splice variants in colon cancer cell lines. The presence of these SVs in human colon tissue samples showed a correlation with histological type of the tissue and gender of patients. The sequencing of the alternatively spliced fragments showed that two have lost the mitochondrial target domain, while the third lacks the heme-binding domain. All SVs retained their sterol binding domain. Translation of these variants would lead to a dysfunctional enzyme without catalytic activity that still binds its substrates therefore they might compete for substrate with the synthesizing and catabolizing enzymes of vitamin D. [ABSTRACT FROM AUTHOR]
- Published
- 2010
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25. The special issue of the ECS2022 meeting in Cork, Ireland.
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Bultynck G, Diercks BP, Kallay E, and Mackrill J
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- 2024
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26. Editorial: The calcium-sensing receptor: from physiology to pharmacology.
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Ranieri M, Schepelmann M, Valenti G, Kallay E, and Riccardi D
- Abstract
Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
- Published
- 2023
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27. Novel Strategies in the Development of New Therapies, Drug Substances, and Drug Carriers Volume II.
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Kutner A, Brown G, and Kallay E
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- Drug Carriers
- Abstract
The highly successful previous Volume 1 [...].
- Published
- 2023
- Full Text
- View/download PDF
28. The Effect of Vitamin D and Its Analogs in Ovarian Cancer.
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Piatek K, Schepelmann M, and Kallay E
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- Calcium, Carcinoma, Ovarian Epithelial drug therapy, Female, Humans, Male, Phosphorus, Vitamin D pharmacology, Vitamin D therapeutic use, Vitamins, Hypercalcemia, Ovarian Neoplasms drug therapy
- Abstract
Ovarian cancer is one of the deadliest cancers in women, due to its heterogeneity and usually late diagnosis. The current first-line therapies of debulking surgery and intensive chemotherapy cause debilitating side effects. Therefore, there is an unmet medical need to find new and effective therapies with fewer side effects, or adjuvant therapies, which could reduce the necessary doses of chemotherapeutics. Vitamin D is one of the main regulators of serum calcium and phosphorus homeostasis, but it has also anticancer effects. It induces differentiation and apoptosis, reduces proliferation and metastatic potential of cancer cells. However, doses that would be effective against cancer cause hypercalcemia. For this reason, synthetic and less calcemic analogs have been developed and tested in terms of their anticancer effect. The anticancer role of vitamin D is best understood in colorectal, breast, and prostate cancer and much less research has been done in ovarian cancer. In this review, we thus summarize the studies on the role of vitamin D and its analogs in vitro and in vivo in ovarian cancer models.
- Published
- 2022
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29. Impaired Mineral Ion Metabolism in a Mouse Model of Targeted Calcium-Sensing Receptor (CaSR) Deletion from Vascular Smooth Muscle Cells.
- Author
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Schepelmann M, Ranieri M, Lopez-Fernandez I, Webberley TS, Brennan SC, Yarova PL, Graca J, Hanif UK, Müller C, Manhardt T, Salzmann M, Quasnichka H, Price SA, Ward DT, Gilbert T, Matchkov VV, Fenton RA, Herberger A, Hwong J, Santa Maria C, Tu CL, Kallay E, Valenti G, Chang W, and Riccardi D
- Subjects
- Animals, Calcium metabolism, Disease Models, Animal, Fibroblast Growth Factors metabolism, Klotho Proteins, Mice, Mice, Knockout, Minerals metabolism, Muscle, Smooth, Vascular metabolism, Myocytes, Smooth Muscle metabolism, Receptors, Calcium-Sensing genetics, Receptors, Calcium-Sensing metabolism, Vascular Calcification etiology
- Abstract
Background: Impaired mineral ion metabolism is a hallmark of CKD-metabolic bone disorder. It can lead to pathologic vascular calcification and is associated with an increased risk of cardiovascular mortality. Loss of calcium-sensing receptor (CaSR) expression in vascular smooth muscle cells exacerbates vascular calcification in vitro. Conversely, vascular calcification can be reduced by calcimimetics, which function as allosteric activators of CaSR., Methods: To determine the role of the CaSR in vascular calcification, we characterized mice with targeted Casr gene knockout in vascular smooth muscle cells (
SM22α CaSRΔflox/Δflox )., Results: Vascular smooth muscle cells cultured from the knockout (KO) mice calcified more readily than those from control (wild-type) mice in vitro. However, mice did not show ectopic calcifications in vivo but they did display a profound mineral ion imbalance. Specifically, KO mice exhibited hypercalcemia, hypercalciuria, hyperphosphaturia, and osteopenia, with elevated circulating fibroblast growth factor 23 (FGF23), calcitriol (1,25-D3 ), and parathyroid hormone levels. Renal tubular α -Klotho protein expression was increased in KO mice but vascular α -Klotho protein expression was not. Altered CaSR expression in the kidney or the parathyroid glands could not account for the observed phenotype of the KO mice., Conclusions: These results suggest that, in addition to CaSR's established role in the parathyroid-kidney-bone axis, expression of CaSR in vascular smooth muscle cells directly contributes to total body mineral ion homeostasis., (Copyright © 2022 by the American Society of Nephrology.)- Published
- 2022
- Full Text
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30. Novel Strategies in the Development of New Therapies, Drug Substances, and Drug Carriers Volume I.
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Kutner A, Brown G, and Kallay E
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- Drug Carriers, Drug Delivery Systems
- Abstract
At present, there is a strong need for new therapies that are effective and safe for widespread diseases [...].
- Published
- 2022
- Full Text
- View/download PDF
31. AOM/DSS Induced Colitis-Associated Colorectal Cancer in 14-Month-Old Female Balb/C and C57/Bl6 Mice-A Pilot Study.
- Author
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Schepelmann M, Kupper N, Gushchina V, Mesteri I, Manhardt T, Moritsch S, Müller C, Piatek K, Salzmann M, Vlasaty A, Eferl R, and Kallay E
- Subjects
- Animals, Azoxymethane, Carcinogenesis, Dextran Sulfate toxicity, Disease Models, Animal, Female, Mice, Mice, Inbred BALB C, Mice, Inbred C57BL, Pilot Projects, Carcinoma, Colitis chemically induced, Colitis complications, Colitis pathology, Colitis-Associated Neoplasms, Colorectal Neoplasms chemically induced, Colorectal Neoplasms pathology
- Abstract
Colitis is a major risk factor for the development of colorectal cancer, leading to colitis-associated colorectal cancer (CAC). The most commonly used animal model to study CAC is the azoxymethane-dextran sulphate-sodium (AOM/DSS) model. The ideal experimental conditions of this model depend on several factors, including the used mouse strain. No data on feasibility and conditions for older mice, e.g., for aging studies, have yet been reported. Thus, we conducted a descriptive, observational pilot study where CAC was induced in 14-month-old female Balb/C and C57/Bl6 mice using 12.5 mg/kg AOM i.p. and three different concentrations of DSS (1, 2, and 3%) in drinking water (ad. lib.). The mice were monitored regularly during the three-month experimental phase. After euthanasia, the colons of the mice were evaluated macroscopically and microscopically. Both the mouse strains showed a DSS-concentration-dependent induction of CAC. Carcinomas were only observed at 3% DSS. The DSS dose was found to be significantly correlated with the histology score and % Ki67 positive cells only in C57/Bl6 mice but not in Balb/C mice, which showed a variable response to the CAC induction. No differences in colon length, weight, or mucin content were observed. Optimal conditions for CAC induction in these aged animals are thus considered to be 3% DSS, as carcinomas did not develop when 2% DSS was used. On the other hand, Balb/C mice reacted severely to 3% DSS, indicating that 2.5% DSS may be the "sweet spot" for future experiments comparing CAC in aged Balb/C and C57/Bl6 mice. This model will allow investigation of the effect of aging on CAC development and therapy.
- Published
- 2022
- Full Text
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32. Vitamin D Analogs Regulate the Vitamin D System and Cell Viability in Ovarian Cancer Cells.
- Author
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Piatek K, Kutner A, Cacsire Castillo-Tong D, Manhardt T, Kupper N, Nowak U, Chodyński M, Marcinkowska E, Kallay E, and Schepelmann M
- Subjects
- Antineoplastic Agents metabolism, Antineoplastic Agents pharmacology, Cell Line, Tumor, Cells, Cultured, Ergocalciferols metabolism, Ergocalciferols pharmacology, Female, Gene Expression Regulation, Neoplastic, Humans, Ovarian Neoplasms enzymology, Ovarian Neoplasms metabolism, Vitamin D analogs & derivatives, Cell Survival, Ovarian Neoplasms drug therapy, Receptors, Calcitriol genetics, Vitamin D pharmacology, Vitamin D3 24-Hydroxylase genetics
- Abstract
Background: Ovarian cancer (OC) is one of the most lethal cancers in women. The active form of vitamin D
3 , 1,25-dihydroxyvitamin D3 (1,25D3 , calcitriol) has anticancer activity in several cancers, including ovarian cancer, but the required pharmacological doses may cause hypercalcemia. We hypothesized that newly developed, low calcemic, vitamin D analogs (an1,25Ds) may be used as anticancer agents instead of calcitriol in ovarian cancer cells., Methods: We used two patient-derived high-grade serous ovarian cancer (HGSOC) cell lines with low (13781) and high (14433) mRNA expression levels of the gene encoding 1,25-dihydroxyvitamin D3 24-hydroxylase CYP24A1 , one of the main target genes of calcitriol. We tested the effect of calcitriol and four structurally related series of an1,25Ds (PRI-1906, PRI-1907, PRI-5201, PRI-5202) on cell number, viability, the expression of CYP24A1 , and the vitamin D receptor (VDR)., Results: CYP24A1 mRNA expression increased in a concentration-dependent manner after treatment with all compounds. In both cell lines, after 4 h, PRI-5202 was the most potent analog (in 13781 cells: EC50 = 2.98 ± 1.10 nmol/L, in 14433 cells: EC50 = 0.92 ± 0.20 nmol/L), while PRI-1907 was the least active one (in 13781 cells: EC50 = n/d, in 14433 cells: EC50 = n/d). This difference among the analogs disappeared after 5 days of treatment. The 13781 cells were more sensitive to the an1,25Ds compared with 14433 cells. The an1,25Ds increased nuclear VDR levels and reduced cell viability, but only in the 13781 cell line., Conclusions: The an1,25Ds had different potencies in the HGSOC cell lines and their efficacy in increasing CYP24A1 expression was cell line- and chemical structure-dependent. Therefore, choosing sensitive cancer cell lines and further optimization of the analogs' structure might lead to new treatment options against ovarian cancer.- Published
- 2021
- Full Text
- View/download PDF
33. Stereo-Specific Modulation of the Extracellular Calcium-Sensing Receptor in Colon Cancer Cells.
- Author
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Schepelmann M, Kupper N, Sladczyk M, Mansfield B, Manhardt T, Piatek K, Iamartino L, Riccardi D, Kariuki BM, Bassetto M, and Kallay E
- Subjects
- Colonic Neoplasms pathology, Gene Expression Regulation, Green Fluorescent Proteins metabolism, HEK293 Cells, HT29 Cells, Humans, Interleukin-8 genetics, Interleukin-8 metabolism, Models, Molecular, Molecular Conformation, Receptors, Calcium-Sensing genetics, Stereoisomerism, Colonic Neoplasms metabolism, Extracellular Space metabolism, Receptors, Calcium-Sensing chemistry, Receptors, Calcium-Sensing metabolism
- Abstract
Pharmacological allosteric agonists (calcimimetics) of the extracellular calcium-sensing receptor (CaSR) have substantial gastro-intestinal side effects and induce the expression of inflammatory markers in colon cancer cells. Here, we compared the effects of both CaSR-specific ( R enantiomers) and -unspecific ( S enantiomers) enantiomers of a calcimimetic (NPS 568) and a calcilytic (allosteric CaSR antagonists; NPS 2143) to prove that these effects are indeed mediated via the CaSR, rather than via off-target effects, e.g., on β-adrenoceptors or calcium channels, of these drugs. The unspecific S enantiomer of NPS 2143 and NPS S- 2143 was prepared using synthetic chemistry and characterized using crystallography. NPS S -2143 was then tested in HEK-293 cells stably transfected with the human CaSR (HEK-CaSR), where it did not inhibit CaSR-mediated intracellular Ca
2+ signals, as expected. HT29 colon cancer cells transfected with the CaSR were treated with both enantiomers of NPS 568 and NPS 2143 alone or in combination, and the expression of CaSR and the pro-inflammatory cytokine interleukin 8 (IL-8) was measured by RT-qPCR and ELISA. Only the CaSR-selective enantiomers of the calcimimetic NPS 568 and NPS 2143 were able to modulate CaSR and IL-8 expression. We proved that pro-inflammatory effects in colon cancer cells are indeed mediated through CaSR activation. The non-CaSR selective enantiomer NPS S- 2143 will be a valuable tool for investigations in CaSR-mediated processes.- Published
- 2021
- Full Text
- View/download PDF
34. Cytomegalovirus Infection Downregulates Vitamin D Receptor in Patients Undergoing Hematopoietic Stem Cell Transplantation.
- Author
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Robak O, Kastner MT, Stecher C, Schneider M, Andreas M, Greinix H, Kallay E, Honsig C, and Steininger C
- Subjects
- Adult, Biomarkers blood, Cytomegalovirus genetics, Cytomegalovirus immunology, Cytomegalovirus Infections immunology, Cytomegalovirus Infections virology, DNA, Viral blood, Down-Regulation, Female, Host-Pathogen Interactions, Humans, Male, Middle Aged, Prospective Studies, Receptors, Calcitriol genetics, Toll-Like Receptor 2 blood, Toll-Like Receptor 2 genetics, Transplantation, Homologous adverse effects, Treatment Outcome, Viral Load, Vitamin D analogs & derivatives, Vitamin D blood, Cytomegalovirus Infections blood, Hematopoietic Stem Cell Transplantation adverse effects, Receptors, Calcitriol blood
- Abstract
Background: Allogeneic hematopoietic stem cell transplantation (HSCT) is a potentially curative option for patients with hematologic diseases but is associated with high mortality and morbidity. Cytomegalovirus (CMV) infection is common in HSCT patients and modulates vitamin D metabolism in vitro. We aimed at validating CMV-associated vitamin D metabolism in vivo in HSCT., Methods: Patients treated for significant CMV viremia after HSCT were evaluated for CMV load before, during, and after antiviral treatment. RNA was isolated from whole-blood samples to test for regulation of key components of the vitamin D receptor (VDR) pathway during different phases of CMV viremia., Results: CMV viremia developed a mean time of 102 (±34) d post-HSCT. Maximum levels of CMV-DNA reached a mean of 5668 (±7257) copies/mL. VDR expression was downregulated to a mean of 64.3% (±42.5%) relative to the VDR expression pre-CMV viremia (P = 0.035) and lagged in recovery following antiviral treatment. Toll-like receptor (TLR) 2 mRNA was upregulated to 225.4% during CMV viremia relative to the expression pre-CMV viremia (P = 0.012) but not TLR6/7/8 and the TLR-adaptor protein MyD88. Levels of 25-OH vitamin D were reduced in all viremic patients (48.0 ± 4.8 versus 25.1 ± 3.7 ng/mL) and were even lower after periods of CMV viremia compared with the control group (48.3 ± 3.5 versus 17.8 ± 1.8 ng/mL; P = 0.008)., Conclusions: CMV viremia is associated with significant dysregulation of vitamin D metabolism in HSCT patients., Competing Interests: The authors declare no conflicts of interest., (Copyright © 2021 Wolters Kluwer Health, Inc. All rights reserved.)
- Published
- 2021
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35. Effects of pharmacological calcimimetics on colorectal cancer cells over-expressing the human calcium-sensing receptor.
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Iamartino L, Elajnaf T, Gall K, David J, Manhardt T, Heffeter P, Grusch M, Derdak S, Baumgartner-Parzer S, Schepelmann M, and Kallay E
- Subjects
- Animals, Caco-2 Cells, Cell Differentiation drug effects, Cell Proliferation drug effects, Colorectal Neoplasms genetics, Colorectal Neoplasms pathology, Gene Expression Regulation, Neoplastic drug effects, Heterografts, Humans, Interleukin-23 Subunit p19 genetics, Interleukin-8 genetics, Mice, Phenethylamines pharmacology, Propylamines pharmacology, Calcimimetic Agents pharmacology, Colorectal Neoplasms drug therapy, Receptors, Calcium-Sensing genetics, Receptors, G-Protein-Coupled genetics
- Abstract
The calcium-sensing receptor (CaSR) is a ubiquitously expressed multifunctional G protein-coupled receptor. Several studies reported that the CaSR plays an anti-inflammatory and anti-tumorigenic role in the intestine, and that it is down-regulated during colorectal carcinogenesis. We hypothesized that positive allosteric CaSR modulators (type II calcimimetics) selectively targeting the intestinal cells could be used for the treatment of intestinal pathologies. Therefore, the aim of this study was to determine the effect of pharmacological stimulation of CaSR on gene expression in vitro and on tumor growth in vivo. We stably transduced two colon cancer cell lines (HT29 and Caco2) with lentiviral vectors containing either the CaSR fused to GFP or GFP only. Using RNA sequencing, RT-qPCR experiments and ELISA, we determined that CaSR over-expression itself had generally little effect on gene expression in these cells. However, treatment with 1 μM of the calcimimetic NPS R-568 increased the expression of pro-inflammatory factors such as IL-23α and IL-8 and reduced the transcription of various differentiation markers in the cells over-expressing the CaSR. In vivo, neither the presence of the CaSR nor p.o. treatment of the animals with the calcimimetic cinacalcet affected tumor growth, tumor cell proliferation or tumor vascularization of murine HT29 xenografts. In summary, CaSR stimulation in CaSR over-expressing cells enhanced the expression of inflammatory markers in vitro, but was not able to repress colorectal cancer tumorigenicity in vivo. These findings suggest potential pro-inflammatory effects of the CaSR and type II calcimimetics in the intestine., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 The Author(s). Published by Elsevier B.V. All rights reserved.)
- Published
- 2020
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36. Insights in Immuno-Nutrition: Vitamin D as a Potent Immunomodulator.
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Untersmayr E and Kallay E
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- COVID-19 complications, Humans, Vitamin D Deficiency complications, Immunologic Factors, Nutritional Status immunology, Vitamin D, Vitamins
- Abstract
The relationship between nutrition and the immune system is a "complicated tango", as coined earlier this year in a review in Nutrients [...].
- Published
- 2020
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37. International Union of Basic and Clinical Pharmacology. CVIII. Calcium-Sensing Receptor Nomenclature, Pharmacology, and Function.
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Leach K, Hannan FM, Josephs TM, Keller AN, Møller TC, Ward DT, Kallay E, Mason RS, Thakker RV, Riccardi D, Conigrave AD, and Bräuner-Osborne H
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- Animals, Binding Sites, GTP-Binding Proteins metabolism, Humans, Models, Molecular, Receptors, Calcium-Sensing chemistry, Receptors, Calcium-Sensing metabolism, Signal Transduction, Small Molecule Libraries pharmacology, Receptors, Calcium-Sensing agonists, Receptors, Calcium-Sensing antagonists & inhibitors
- Abstract
The calcium-sensing receptor (CaSR) is a class C G protein-coupled receptor that responds to multiple endogenous agonists and allosteric modulators, including divalent and trivalent cations, L-amino acids, γ -glutamyl peptides, polyamines, polycationic peptides, and protons. The CaSR plays a critical role in extracellular calcium (Ca
2+ o ) homeostasis, as demonstrated by the many naturally occurring mutations in the CaSR or its signaling partners that cause Ca2+ o homeostasis disorders. However, CaSR tissue expression in mammals is broad and includes tissues unrelated to Ca2+ o homeostasis, in which it, for example, regulates the secretion of digestive hormones, airway constriction, cardiovascular effects, cellular differentiation, and proliferation. Thus, although the CaSR is targeted clinically by the positive allosteric modulators (PAMs) cinacalcet, evocalcet, and etelcalcetide in hyperparathyroidism, it is also a putative therapeutic target in diabetes, asthma, cardiovascular disease, and cancer. The CaSR is somewhat unique in possessing multiple ligand binding sites, including at least five putative sites for the "orthosteric" agonist Ca2+ o , an allosteric site for endogenous L-amino acids, two further allosteric sites for small molecules and the peptide PAM, etelcalcetide, and additional sites for other cations and anions. The CaSR is promiscuous in its G protein-coupling preferences, and signals via Gq/11 , Gi/o , potentially G12/13 , and even Gs in some cell types. Not surprisingly, the CaSR is subject to biased agonism, in which distinct ligands preferentially stimulate a subset of the CaSR's possible signaling responses, to the exclusion of others. The CaSR thus serves as a model receptor to study natural bias and allostery. SIGNIFICANCE STATEMENT: The calcium-sensing receptor (CaSR) is a complex G protein-coupled receptor that possesses multiple orthosteric and allosteric binding sites, is subject to biased signaling via several different G proteins, and has numerous (patho)physiological roles. Understanding the complexities of CaSR structure, function, and biology will aid future drug discovery efforts seeking to target this receptor for a diversity of diseases. This review summarizes what is known to date regarding key structural, pharmacological, and physiological features of the CaSR., (Copyright © 2020 by The American Society for Pharmacology and Experimental Therapeutics.)- Published
- 2020
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38. Sensing Extracellular Calcium - An Insight into the Structure and Function of the Calcium-Sensing Receptor (CaSR).
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Chavez-Abiega S, Mos I, Centeno PP, Elajnaf T, Schlattl W, Ward DT, Goedhart J, and Kallay E
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- Cinacalcet therapeutic use, Humans, Kidney metabolism, Parathyroid Glands metabolism, Renal Insufficiency, Chronic complications, Calcium metabolism, Hyperparathyroidism, Secondary drug therapy, Hyperparathyroidism, Secondary etiology, Receptors, Calcium-Sensing chemistry, Receptors, Calcium-Sensing metabolism
- Abstract
The calcium-sensing receptor (CaSR) is a G protein-coupled receptor that plays a key role in calcium homeostasis, by sensing free calcium levels in blood and regulating parathyroid hormone secretion in response. The CaSR is highly expressed in parathyroid gland and kidney where its role is well characterised, but also in other tissues where its function remains to be determined. The CaSR can be activated by a variety of endogenous ligands, as well as by synthetic modulators such as Cinacalcet, used in the clinic to treat secondary hyperparathyroidism in patients with chronic kidney disease. The CaSR couples to multiple G proteins, in a tissue-specific manner, activating several signalling pathways and thus regulating diverse intracellular events. The multifaceted nature of this receptor makes it a valuable therapeutic target for calciotropic and non-calciotropic diseases. It is therefore essential to understand the complexity behind the pharmacology, trafficking, and signalling characteristics of this receptor. This review provides an overview of the latest knowledge about the CaSR and discusses future hot topics in this field.
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- 2020
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39. Switching to a Healthy Diet Prevents the Detrimental Effects of Western Diet in a Colitis-Associated Colorectal Cancer Model.
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Gröschel C, Prinz-Wohlgenannt M, Mesteri I, Karuthedom George S, Trawnicek L, Heiden D, Aggarwal A, Tennakoon S, Baumgartner M, Gasche C, Lang M, Marculescu R, Manhardt T, Schepelmann M, and Kallay E
- Subjects
- Aberrant Crypt Foci pathology, Animals, Azoxymethane administration & dosage, Colon pathology, Colorectal Neoplasms etiology, Colorectal Neoplasms pathology, Dextran Sulfate administration & dosage, Disease Models, Animal, Female, Gastrointestinal Microbiome physiology, Liver enzymology, Mice, Mice, Inbred BALB C, Vitamin D metabolism, Colitis chemically induced, Colitis complications, Colorectal Neoplasms prevention & control, Diet, Healthy, Diet, Western adverse effects
- Abstract
Inflammatory bowel disease increases the odds of developing colitis-associated cancer. We hypothesized that Western-style diet (WD) aggravates azoxymethane (AOM)/dextran sulfate sodium salt (DSS)-induced colitis-associated tumorigenesis and that switching to the standard AIN93G diet will ameliorate disease symptoms even after cancer initiation. Female BALB/c mice received either WD (WD group) or standard AIN93G diet (AIN group) for the whole experimental period. After five weeks, the mice received 12.5 mg/kg AOM intraperitoneally, followed by three DSS cycles. In one group of mice, the WD was switched to AIN93G the day before starting the first DSS cycle (WD/AIN group). Feeding the WD during the whole experimental period aggravated colitis symptoms, shortened the colon ( p < 0.05), changed microbiota composition and increased tumor promotion. On molecular level, the WD reduced proliferation ( p < 0.05) and increased expression of the vitamin D catabolizing enzyme Cyp24a1 ( p < 0.001). The switch to the AIN93G diet ameliorated this effect, reflected by longer colons, fewer ( p < 0.05) and smaller ( p < 0.01) aberrant colonic crypt foci, comparable with the AIN group. Our results show that switching to a healthy diet, even after cancer initiation is able to revert the deleterious effect of the WD and could be an effective preventive strategy to reduce colitis symptoms and prevent tumorigenesis.
- Published
- 2019
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40. Nutritional and Pharmacological Targeting of the Calcium-Sensing Receptor Influences Chemically Induced Colitis in Mice.
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Elajnaf T, Iamartino L, Mesteri I, Müller C, Bassetto M, Manhardt T, Baumgartner-Parzer S, Kallay E, and Schepelmann M
- Subjects
- Animals, Colitis chemically induced, Colon metabolism, Cytokines metabolism, Dextran Sulfate, Female, Inflammation, Intestinal Mucosa metabolism, Mice, Mice, Inbred BALB C, Naphthalenes administration & dosage, Calcium, Dietary pharmacology, Colitis metabolism, Diet, High-Protein adverse effects, Dietary Proteins pharmacology, Receptors, Calcium-Sensing agonists
- Abstract
The calcium-sensing receptor (CaSR) is the main regulator of extracellular Ca
2+ homeostasis. It has diverse functions in different tissues, including the intestines. Intestine-specific knockout of the CaSR renders mice more susceptible to dextran sulphate sodium (DSS)-induced colitis. To test our hypothesis that the CaSR reduces intestinal inflammation, we assessed the effects of nutritional and pharmacological agonists of the CaSR in a colitis model. We treated female Balb/C mice with dietary calcium and protein (nutritional agonists of the CaSR) or pharmacological CaSR modulators (the agonists cinacalcet and GSK3004774, and the antagonist NPS-2143; 10 mg/kg), then induced colitis with DSS. The high-protein diet had a strong pro-inflammatory effect-it shortened the colons (5.3 ± 0.1 cm vs. 6.1 ± 0.2 cm normal diet, p < 0.05), lowered mucin expression and upregulated pro-inflammatory cytokines, such as interferon-γ, (4.2-fold, p < 0.05) compared with the normal diet. Cinacalcet reduced mucin expression, which coincided with an increase in tumor necrosis factor-α (4.4-fold, p < 0.05) and IL-6 (4.9-fold, p < 0.05) in the plasma, compared with vehicle. The CaSR antagonist, NPS-2143, significantly reduced the cumulative inflammation score compared with the vehicle control (35.3 ± 19.1 vs. 21.9 ± 14.3 area under the curve, p < 0.05) and reduced infiltration of inflammatory cells. While dietary modulation of the CaSR had no beneficial effects, pharmacological inhibition of the CaSR may have the potential of a novel add-on therapy in the treatment of inflammatory bowel diseases.- Published
- 2019
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41. The calcium-sensing receptor in physiology and in calcitropic and noncalcitropic diseases.
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Hannan FM, Kallay E, Chang W, Brandi ML, and Thakker RV
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- Female, Gene Expression Regulation, Genetic Predisposition to Disease epidemiology, Humans, Hypercalcemia drug therapy, Hypercalcemia genetics, Hypercalcemia physiopathology, Hypercalciuria drug therapy, Hypercalciuria physiopathology, Hypocalcemia drug therapy, Hypocalcemia physiopathology, Hypoparathyroidism drug therapy, Hypoparathyroidism genetics, Hypoparathyroidism physiopathology, Incidence, Male, Mutation genetics, Nephrolithiasis drug therapy, Nephrolithiasis physiopathology, Prognosis, Receptors, Calcium-Sensing drug effects, Risk Assessment, Treatment Outcome, Calcimimetic Agents therapeutic use, Hypercalcemia congenital, Hypercalciuria genetics, Hypocalcemia genetics, Hypoparathyroidism congenital, Nephrolithiasis genetics, Receptors, Calcium-Sensing genetics
- Abstract
The Ca
2+ -sensing receptor (CaSR) is a dimeric family C G protein-coupled receptor that is expressed in calcitropic tissues such as the parathyroid glands and the kidneys and signals via G proteins and β-arrestin. The CaSR has a pivotal role in bone and mineral metabolism, as it regulates parathyroid hormone secretion, urinary Ca2+ excretion, skeletal development and lactation. The importance of the CaSR for these calcitropic processes is highlighted by loss-of-function and gain-of-function CaSR mutations that cause familial hypocalciuric hypercalcaemia and autosomal dominant hypocalcaemia, respectively, and also by the fact that alterations in parathyroid CaSR expression contribute to the pathogenesis of primary and secondary hyperparathyroidism. Moreover, the CaSR is an established therapeutic target for hyperparathyroid disorders. The CaSR is also expressed in organs not involved in Ca2+ homeostasis: it has noncalcitropic roles in lung and neuronal development, vascular tone, gastrointestinal nutrient sensing, wound healing and secretion of insulin and enteroendocrine hormones. Furthermore, the abnormal expression or function of the CaSR is implicated in cardiovascular and neurological diseases, as well as in asthma, and the CaSR is reported to protect against colorectal cancer and neuroblastoma but increase the malignant potential of prostate and breast cancers.- Published
- 2018
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42. Calcium-sensing receptor in colorectal inflammation and cancer: Current insights and future perspectives.
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Iamartino L, Elajnaf T, Kallay E, and Schepelmann M
- Subjects
- Animals, Antineoplastic Agents pharmacology, Biomarkers, Tumor analysis, Biomarkers, Tumor antagonists & inhibitors, Biomarkers, Tumor metabolism, Cell Differentiation drug effects, Cell Proliferation drug effects, Cell Transformation, Neoplastic pathology, Colitis complications, Colitis drug therapy, Colon metabolism, Colon pathology, Colorectal Neoplasms drug therapy, Colorectal Neoplasms etiology, Colorectal Neoplasms mortality, Disease Progression, Down-Regulation, Gastrointestinal Agents pharmacology, Humans, Prognosis, Receptors, Calcium-Sensing analysis, Receptors, Calcium-Sensing antagonists & inhibitors, Signal Transduction drug effects, Antineoplastic Agents therapeutic use, Colitis pathology, Colorectal Neoplasms pathology, Gastrointestinal Agents therapeutic use, Receptors, Calcium-Sensing metabolism
- Abstract
The extracellular calcium-sensing receptor (CaSR) is best known for its action in the parathyroid gland and kidneys where it controls body calcium homeostasis. However, the CaSR has different roles in the gastrointestinal tract, where it is ubiquitously expressed. In the colon, the CaSR is involved in controlling multiple mechanisms, including fluid transport, inflammation, cell proliferation and differentiation. Although the expression pattern and functions of the CaSR in the colonic microenvironment are far from being completely understood, evidence has been accumulating that the CaSR might play a protective role against both colonic inflammation and colorectal cancer. For example, CaSR agonists such as dipeptides have been suggested to reduce colonic inflammation, while dietary calcium was shown to reduce the risk of colorectal cancer. CaSR expression is lost in colonic malignancies, indicating that the CaSR is a biomarker for colonic cancer progression. This dual anti-inflammatory and anti-tumourigenic role of the CaSR makes it especially interesting in colitis-associated colorectal cancer. In this review, we describe the clinical and experimental evidence for the role of the CaSR in colonic inflammation and colorectal cancer, the intracellular signalling pathways which are putatively involved in these actions, and the possibilities to exploit these actions of the CaSR for future therapies of colonic inflammation and cancer., Competing Interests: Conflict-of-interest statement: No potential conflicts of interest.
- Published
- 2018
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43. Editorial: Physiology and Pathophysiology of the Extracellular Calcium-Sensing Receptor.
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Kallay E
- Published
- 2018
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44. Effects of human interleukins in the transgenic gene reporter cell lines IZ-VDRE and IZ-CYP24 designed to assess the transcriptional activity of vitamin D receptor.
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Bartonkova I, Kallay E, and Dvorak Z
- Subjects
- 25-Hydroxyvitamin D3 1-alpha-Hydroxylase genetics, Cell Line, Humans, Transfection, Vitamin D3 24-Hydroxylase genetics, Genes, Reporter genetics, Interleukins pharmacology, Receptors, Calcitriol genetics, Transcription, Genetic drug effects, Transgenes genetics
- Abstract
The role of vitamin D receptor (VDR) in immune responses has been broadly studied and it has been shown that activated VDR alters the levels of some interleukins (ILs). In this study, we studied the opposite, i.e. whether 13 selected pro-inflammatory and anti-inflammatory ILs influence the transcriptional activity of human VDR. The experimental models of choice were two human stably transfected gene reporter cell lines IZ-VDRE and IZ-CYP24, which were designed to evaluate the transcriptional activity of VDR. The gene reporter assays revealed inhibition of calcitriol-induced luciferase activity by IL-4 and IL-13, when 1 ng/mL of these two compounds decreased the effect of calcitriol down to 60% of the control value. Consistently, calcitriol-induced expression of CYP24A1 mRNA was also significantly decreased by IL-4 and IL-13. The expression of VDR and CYP27B1 mRNAs was not influenced by any of the 13 tested ILs. These data suggest possible cross-talk between the VDR signalling pathway and IL-4- and IL-13-mediated cell signalling.
- Published
- 2018
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45. Are male cancer patients more affected by losing their jobs than female patients? Gender as a moderator of the relationship between losing the job and well-being in a sample of Romanian cancer patients.
- Author
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Kallay E, Degi CL, and Pintea S
- Subjects
- Female, Gender Identity, Humans, Male, Middle Aged, Romania, Stress, Psychological, Employment trends, Neoplasms epidemiology
- Abstract
Purpose: Research indicates the heightened need of cancer patients to return to work, which would be beneficial for their emotional/mental health and well-being. The major aim of this study was to identify the overall effect of losing the job upon different dimensions of well-being, and possible gender differences related to this influence., Methods: A sample of 800 Romanian cancer patients was screened in 2014 (461 female and 338 male)., Results: Our results indicate that losing one's job after being diagnosed with cancer affects male more than female patients on the physical, emotional, and functional dimensions of well-being. Furthermore, male patients perceive a higher level of interference between illness/treatment and paid work than female patients, and perceive themselves less able to work than female cancer patients. Also the fulfillment derived from work perceived by male patients is lower than that of female cancer patients., Conclusion: Counselors and therapists should focus on enlarging the patients' pool of alternative sources of meaning, thus enhancing their well-being and implicitly their clinical recovery.
- Published
- 2017
46. Mutant Mice With Calcium-Sensing Receptor Activation Have Hyperglycemia That Is Rectified by Calcilytic Therapy.
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Babinsky VN, Hannan FM, Ramracheya RD, Zhang Q, Nesbit MA, Hugill A, Bentley L, Hough TA, Joynson E, Stewart M, Aggarwal A, Prinz-Wohlgenannt M, Gorvin CM, Kallay E, Wells S, Cox RD, Richards D, Rorsman P, and Thakker RV
- Subjects
- Animals, Body Composition, Calcium metabolism, Cell Proliferation, Glucose Intolerance, HEK293 Cells, Humans, Islets of Langerhans cytology, Islets of Langerhans physiology, Mice, Mice, Knockout, Mutation, Receptors, Calcium-Sensing antagonists & inhibitors, Receptors, Calcium-Sensing genetics, Receptors, G-Protein-Coupled antagonists & inhibitors, Receptors, G-Protein-Coupled genetics, Hyperglycemia drug therapy, Hyperglycemia genetics, Indans pharmacology, Phenylpropionates pharmacology, Receptors, Calcium-Sensing metabolism, Receptors, G-Protein-Coupled metabolism
- Abstract
The calcium-sensing receptor (CaSR) is a family C G-protein-coupled receptor that plays a pivotal role in extracellular calcium homeostasis. The CaSR is also highly expressed in pancreatic islet α- and β-cells that secrete glucagon and insulin, respectively. To determine whether the CaSR may influence systemic glucose homeostasis, we characterized a mouse model with a germline gain-of-function CaSR mutation, Leu723Gln, referred to as Nuclear flecks (Nuf). Heterozygous- (CasrNuf/+) and homozygous-affected (CasrNuf/Nuf) mice were shown to have hypocalcemia in association with impaired glucose tolerance and insulin secretion. Oral administration of a CaSR antagonist compound, known as a calcilytic, rectified the glucose intolerance and hypoinsulinemia of CasrNuf/+ mice and ameliorated glucose intolerance in CasrNuf/Nuf mice. Ex vivo studies showed CasrNuf/+ and CasrNuf/Nuf mice to have reduced pancreatic islet mass and β-cell proliferation. Electrophysiological analysis of isolated CasrNuf/Nuf islets showed CaSR activation to increase the basal electrical activity of β-cells independently of effects on the activity of the adenosine triphosphate (ATP)-sensitive K+ (KATP) channel. CasrNuf/Nuf mice also had impaired glucose-mediated suppression of glucagon secretion, which was associated with increased numbers of α-cells and a higher α-cell proliferation rate. Moreover, CasrNuf/Nuf islet electrophysiology demonstrated an impairment of α-cell membrane depolarization in association with attenuated α-cell basal KATP channel activity. These studies indicate that the CaSR activation impairs glucose tolerance by a combination of α- and β-cell defects and also influences pancreatic islet mass. Moreover, our findings highlight a potential application of targeted CaSR compounds for modulating glucose metabolism.
- Published
- 2017
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47. Expression profiling of colorectal cancer cells reveals inhibition of DNA replication licensing by extracellular calcium.
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Aggarwal A, Schulz H, Manhardt T, Bilban M, Thakker RV, and Kallay E
- Subjects
- Caco-2 Cells, Colorectal Neoplasms pathology, HT29 Cells, Humans, RNA, Messenger genetics, Calcium metabolism, Colorectal Neoplasms genetics, DNA Replication, Gene Expression Profiling
- Abstract
Colorectal cancer is one of the most common cancers in industrialised societies. Epidemiological studies, animal experiments, and randomized clinical trials have shown that dietary factors can influence all stages of colorectal carcinogenesis, from initiation through promotion to progression. Calcium is one of the factors with a chemoprophylactic effect in colorectal cancer. The aim of this study was to understand the molecular mechanisms of the anti-tumorigenic effects of extracellular calcium ([Ca
2+ ]o ) in colon cancer cells. Gene expression microarray analysis of colon cancer cells treated for 1, 4, and 24h with 2mM [Ca2+ ]o identified significant changes in expression of 1571 probe sets (ANOVA, p<10-5 ). The main biological processes affected by [Ca2+ ]o were DNA replication, cell division, and regulation of transcription. All factors involved in DNA replication-licensing were significantly downregulated by [Ca2+ ]o . Furthermore, we show that the calcium-sensing receptor (CaSR), a G protein-coupled receptor is a mediator involved in this process. To test whether these results were physiologically relevant, we fed mice with a standard diet containing low (0.04%), intermediate (0.1%), or high (0.9%) levels of dietary calcium. The main molecules regulating replication licensing were inhibited also in vivo, in the colon of mice fed high calcium diet. We show that among the mechanisms behind the chemopreventive effect of [Ca2+ ]o is inhibition of replication licensing, a process often deregulated in neoplastic transformation. Our data suggest that dietary calcium is effective in preventing replicative stress, one of the main drivers of cancer and this process is mediated by the calcium-sensing receptor., (Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.)- Published
- 2017
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48. Vitamin D 3 Loading Is Superior to Conventional Supplementation After Weight Loss Surgery in Vitamin D-Deficient Morbidly Obese Patients: a Double-Blind Randomized Placebo-Controlled Trial.
- Author
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Luger M, Kruschitz R, Kienbacher C, Traussnigg S, Langer FB, Prager G, Schindler K, Kallay E, Hoppichler F, Trauner M, Krebs M, Marculescu R, and Ludvik B
- Subjects
- Adult, Dietary Supplements, Double-Blind Method, Female, Humans, Hyperparathyroidism, Secondary complications, Liver Cirrhosis complications, Male, Middle Aged, Non-alcoholic Fatty Liver Disease complications, Obesity, Morbid surgery, Postoperative Period, Prevalence, Vitamin D therapeutic use, Vitamin D Deficiency drug therapy, Weight Loss, Cholecalciferol administration & dosage, Gastric Bypass, Obesity, Morbid complications, Vitamin D Deficiency complications, Vitamins administration & dosage
- Abstract
Background: Bariatric patients often suffer from vitamin D deficiency (VDD), and both, morbid obesity and VDD, are related to non-alcoholic fatty liver disease. However, limited data are available regarding best strategies for treating VDD, particularly, in bariatric patients undergoing omega-loop gastric bypass (OLGB). Therefore, we examined the efficacy and safety of a forced vitamin D dosing regimen and intervention effects in liver fibrotic patients., Methods: In this double-blind, randomized, placebo-controlled trial, 50 vitamin D-deficient patients undergoing OLGB were randomly assigned to receive, in the first month postoperatively, oral vitamin D
3 (≤3 doses of 100,000 IU; intervention group) or placebo as loading dose (control group) with subsequent maintenance dose (3420 IU/day) in both groups until 6-month visit., Results: Compared with control group, higher increase of 25(OH)D (67.9 (21.1) vs. 55.7 nmol/L (21.1); p = 0.049) with lower prevalence of secondary hyperparathyroidism (10 vs. 24 %; p = 0.045) was observed in intervention group. No (serious) adverse events related to study medication were found. The loading dose regimen was more effective in increasing 25(OH)D in patients with significant liver fibrosis while this was not the case for conventional supplementation (placebo with maintenance dose) (71.5 (20.5) vs. 22.5 nmol/L (13.8); p = 0.022; n = 14)., Conclusions: Our findings indicate that a high vitamin D3 loading dose, in the first month postoperatively, with subsequent maintenance dose is effective and safe in achieving higher vitamin D concentrations in OLGB patients. Unexpectedly, it is more effective in patients with significant liver fibrosis which is of potentially high clinical relevance and requires further investigation.- Published
- 2017
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49. Human cytomegalovirus infection downregulates vitamin-D receptor in mammalian cells.
- Author
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Rieder FJJ, Gröschel C, Kastner MT, Kosulin K, Laengle J, Zadnikar R, Marculescu R, Schneider M, Lion T, Bergmann M, Kallay E, and Steininger C
- Subjects
- 25-Hydroxyvitamin D3 1-alpha-Hydroxylase metabolism, A549 Cells, Adenoviridae, Animals, Cell Line, Tumor, Chlorocebus aethiops, Cytomegalovirus, Dose-Response Relationship, Drug, Down-Regulation, Fibroblasts metabolism, Fibroblasts virology, Gene Expression Regulation, Humans, Orthomyxoviridae, Vero Cells, Vitamin D metabolism, Vitamin D3 24-Hydroxylase metabolism, Cytomegalovirus Infections metabolism, Receptors, Calcitriol metabolism
- Abstract
Vitamin D (VD) is essential for the human body and involved in a wide variety of critical physiological processes including bone, muscle, and cardiovascular health, as well as innate immunity and antimicrobial responses. Here, we elucidated the significance of the VD system in cytomegalovirus (CMV) infection, which is one of the most common opportunistic infections in immunocompromised or -suppressed patients. We found that expression of vitamin D receptor (VDR) was downregulated in CMV-infected cells within 12h [hrs] post infection [p.i.] to 12% relative to VDR expression in mock-infected fibroblasts and did not recover during the CMV replication cycle of 96h. None of the biologically active metabolites of VD, cholecalciferol, calcidiol, or calcitriol, inhibit CMV replication significantly in human fibroblasts. In a feedback loop, expression of CYP24A1 dropped to 3% by 12h p.i. and expression of CYP27B1 increased gradually during the replication cycle of CMV to 970% probably as a consequence of VDR inhibition. VDR expression was not downregulated during influenza virus or adenovirus replication. The potent synthetic vitamin D analog EB-1089 was not able to inhibit CMV replication or antagonize its effect on VDR expression. Only CMV replication, and none of the other viral pathogens evaluated, inhibited the vitamin D system in vitro. In view of the pleiotropism of VDR, CMV-mediated downregulation may have far-reaching virological, immunological, and clinical implications and thus warrant further evaluations in vitro and in vivo., (Copyright © 2016 Elsevier Ltd. All rights reserved.)
- Published
- 2017
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50. The Calcilytic Agent NPS 2143 Rectifies Hypocalcemia in a Mouse Model With an Activating Calcium-Sensing Receptor (CaSR) Mutation: Relevance to Autosomal Dominant Hypocalcemia Type 1 (ADH1).
- Author
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Hannan FM, Walls GV, Babinsky VN, Nesbit MA, Kallay E, Hough TA, Fraser WD, Cox RD, Hu J, Spiegel AM, and Thakker RV
- Subjects
- Animals, Disease Models, Animal, Female, HEK293 Cells, Humans, Hypercalcemia drug therapy, Hypercalcemia genetics, Male, Mice, Mutation, Receptors, Calcium-Sensing, Hypercalcemia congenital, Naphthalenes therapeutic use, Receptors, G-Protein-Coupled genetics
- Abstract
Autosomal dominant hypocalcemia type 1 (ADH1) is caused by germline gain-of-function mutations of the calcium-sensing receptor (CaSR) and may lead to symptomatic hypocalcemia, inappropriately low serum PTH concentrations and hypercalciuria. Negative allosteric CaSR modulators, known as calcilytics, have been shown to normalize the gain-of-function associated with ADH-causing CaSR mutations in vitro and represent a potential targeted therapy for ADH1. However, the effectiveness of calcilytic drugs for the treatment of ADH1-associated hypocalcemia remains to be established. We have investigated NPS 2143, a calcilytic compound, for the treatment of ADH1 by in vitro and in vivo studies involving a mouse model, known as Nuf, which harbors a gain-of-function CaSR mutation, Leu723Gln. Wild-type (Leu723) and Nuf mutant (Gln723) CaSRs were expressed in HEK293 cells, and the effect of NPS 2143 on their intracellular calcium responses was determined by flow cytometry. NPS 2143 was also administered as a single ip bolus to wild-type and Nuf mice and plasma concentrations of calcium and PTH, and urinary calcium excretion measured. In vitro administration of NPS 2143 decreased the intracellular calcium responses of HEK293 cells expressing the mutant Gln723 CaSR in a dose-dependent manner, thereby rectifying the gain-of-function associated with the Nuf mouse CaSR mutation. Intraperitoneal injection of NPS 2143 in Nuf mice led to significant increases in plasma calcium and PTH without elevating urinary calcium excretion. These studies of a mouse model with an activating CaSR mutation demonstrate NPS 2143 to normalize the gain-of-function causing ADH1 and improve the hypocalcemia associated with this disorder.
- Published
- 2015
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