@article{WittenbecherOuniKuxhausetal.2019, author = {Wittenbecher, Clemens and Ouni, Meriem and Kuxhaus, Olga and J{\"a}hnert, Markus and Gottmann, Pascal and Teichmann, Andrea and Meidtner, Karina and Kriebel, Jennifer and Grallert, Harald and Pischon, Tobias and Boeing, Heiner and Schulze, Matthias Bernd and Sch{\"u}rmann, Annette}, title = {Insulin-Like Growth Factor Binding Protein 2 (IGFBP-2) and the Risk of Developing Type 2 Diabetes}, series = {Diabetes : a journal of the American Diabetes Association}, volume = {68}, journal = {Diabetes : a journal of the American Diabetes Association}, number = {1}, publisher = {American Diabetes Association}, address = {Alexandria}, issn = {0012-1797}, doi = {10.2337/db18-0620}, pages = {188 -- 197}, year = {2019}, abstract = {Recent studies suggest that insulin-like growth factor binding protein 2 (IGFBP-2) may protect against type 2 diabetes, but population-based human studies are scarce. We aimed to investigate the prospective association of circulating IGFBP-2 concentrations and of differential methylation in the IGFBP-2 gene with type 2 diabetes risk.}, language = {en} } @article{RawelMeidtnerKroll2005, author = {Rawel, Harshadrai Manilal and Meidtner, Karina and Kroll, J{\"u}rgen}, title = {Binding of selected phenolic compounds to proteins}, issn = {0021-8561}, year = {2005}, abstract = {In the context of this study, the noncovalent binding of selected phenolic compounds (chlorogenic, ferulic, and gallic acids, quercetin, rutin, and isocluercetin) to different proteins (human serum albumin, bovine serum albumin, soy glycinin, and lysozyme) was studied with direct (Hummel- Dreyer/size exclusion chromatography) and/or indirect methods (fluorescence absorbance properties of the binding components). In the latter case, the measurement of the phenol binding was achieved by exploiting the intrinsic fluorescence emission properties of cluercetin as a probe. From the data obtained, the binding constants and the number of binding sites were calculated. The binding parameters were influenced by different factors, where, e.g., increasing temperature and ionic strength as well as decreasing pH cause a diminished binding. The structures of the proteins as determined by circular dichroism indicate changes in the tertiary structure with the secondary structure remaining intact}, language = {en} } @article{RawelFreyMeidtneretal.2006, author = {Rawel, Harshadrai Manilal and Frey, Simone K. and Meidtner, Karina and Kroll, J{\"u}rgen and Schweigert, Florian J.}, title = {Determining the binding affinities of phenolic compounds to proteins by quenching of the intrinsic tryptophan fluorescence}, series = {Molecular nutrition \& food research : bioactivity, chemistry, immunology, microbiology, safety, technology}, volume = {50}, journal = {Molecular nutrition \& food research : bioactivity, chemistry, immunology, microbiology, safety, technology}, number = {8}, publisher = {Wiley}, address = {Weinheim}, issn = {1613-4125}, doi = {10.1002/mnfr.200600013}, pages = {705 -- 713}, year = {2006}, abstract = {The noncovalent binding of selected phenolic compounds (chlorogenic-, ferutic-, gallic acid, quercetin, rutin, and isoquercetin) to proteins (HSA, BSA, soy glycinin, and lysozyme) was studied by an indirect method applying the quenching of intrinsic tryptophan fluorescence. From the data obtained, the binding constants were calculated by nonlinear regression (one site binding; y = Bx/k + x). It has been reported that tannins inhibit human salivary amylase and that these complexes may reduce the development of cariogenic plaques. Further, amylase contains two tryptophan residues in its active site. Therefore, in a second part of the study involving 31 human subjects, evidence was sought for noncovalent interactions between the phenols of green tea and saliva proteins as measured by the fluorescence intensity. Amylase activity was determined before and after the addition of green tea to saliva of 31 subjects. Forty percent of the subjects showed an increase in amylase activity contrary to studies reporting only a decrease in activity. The interactions of tannin with amylase result in a decrease of its activity. It still remains to be elucidated why amylase does not react uniformly under conditions of applying green tea to saliva. Further, in terms of using phenols as caries inhibitors this finding should be of importance.}, language = {en} } @article{KroegerMeidtnerStefanetal.2018, author = {Kroeger, Janine and Meidtner, Karina and Stefan, Norbert and Guevara, Marcela and Kerrison, Nicola D. and Ardanaz, Eva and Aune, Dagfinn and Boeing, Heiner and Dorronsoro, Miren and Dow, Courtney and Fagherazzi, Guy and Franks, Paul W. and Freisling, Heinz and Gunter, Marc J. and Maria Huerta, Jose and Kaaks, Rudolf and Key, Timothy J. and Khaw, Kay Tee and Krogh, Vittorio and Kuehn, Tilman and Mancini, Francesca Romana and Mattiello, Amalia and Nilsson, Peter M. and Olsen, Anja and Overvad, Kim and Palli, Domenico and Ramon Quiros, J. and Rolandsson, Olov and Sacerdote, Carlotta and Sala, Nuria and Salamanca-Fernandez, Elena and Sluijs, Ivonne and Spijkerman, Annemieke M. W. and Tjonneland, Anne and Tsilidis, Konstantinos K. and Tumino, Rosario and van der Schouw, Yvonne T. and Forouhi, Nita G. and Sharp, Stephen J. and Langenberg, Claudia and Riboli, Elio and Schulze, Matthias Bernd and Wareham, Nicholas J.}, title = {Circulating Fetuin-A and Risk of Type 2 Diabetes}, series = {Diabetes : a journal of the American Diabetes Association}, volume = {67}, journal = {Diabetes : a journal of the American Diabetes Association}, number = {6}, publisher = {American Diabetes Association}, address = {Alexandria}, issn = {0012-1797}, doi = {10.2337/db17-1268}, pages = {1200 -- 1205}, year = {2018}, abstract = {Fetuin-A, a hepatic-origin protein, is strongly positively associated with risk of type 2 diabetes in human observational studies, but it is unknown whether this association is causal. Weaimed to study the potential causal relation of circulating fetuin-A to risk of type 2 diabetes in a Mendelian randomization study with single nucleotide polymorphisms located in the fetuin-A-encoding AHSG gene. We used data from eight European countries of the European Prospective Investigation into Cancer and Nutrition (EPIC)-InterAct case-cohort study including 10,020 incident cases. Plasma fetuin-A concentration was measured in a subset of 965 subcohort participants and 654 case subjects. A genetic score of the AHSG single nucleotide polymorphisms was strongly associated with fetuin-A (28\% explained variation). Using the genetic score as instrumental variable of fetuin-A, we observed no significant association of a 50 mu g/mL higher fetuin-A concentration with diabetes risk (hazard ratio 1.02 [95\% CI 0.97, 1.07]). Combining our results with those from the DIAbetes Genetics Replication And Meta-analysis (DIAGRAM) consortium (12,171 case subjects) also did not suggest a clear significant relation of fetuin-A with diabetes risk. In conclusion, although there is mechanistic evidence for an effect of fetuin-A on insulin sensitivity and secretion, this study does not support a strong, relevant relationship between circulating fetuin-A and diabetes risk in the general population.}, language = {en} } @misc{DietrichJacobsZhengetal.2019, author = {Dietrich, Stefan and Jacobs, Simone and Zheng, Ju-Sheng and Meidtner, Karina and Schwingshackl, Lukas and Schulze, Matthias Bernd}, title = {Gene-lifestyle interaction on risk of type 2 diabetes}, series = {Obesity reviews : an official journal of the International Association for the Study of Obesity}, volume = {20}, journal = {Obesity reviews : an official journal of the International Association for the Study of Obesity}, number = {11}, publisher = {Wiley}, address = {Hoboken}, issn = {1467-7881}, doi = {10.1111/obr.12921}, pages = {1557 -- 1571}, year = {2019}, abstract = {The pathophysiological influence of gene-lifestyle interactions on the risk to develop type 2 diabetes (T2D) is currently under intensive research. This systematic review summarizes the evidence for gene-lifestyle interactions regarding T2D incidence. MEDLINE, EMBASE, and Web of Science were systematically searched until 31 January 2019 to identify publication with (a) prospective study design; (b) T2D incidence; (c) gene-diet, gene-physical activity, and gene-weight loss intervention interaction; and (d) population who are healthy or prediabetic. Of 66 eligible publications, 28 reported significant interactions. A variety of different genetic variants and dietary factors were studied. Variants at TCF7L2 were most frequently investigated and showed interactions with fiber and whole grain on T2D incidence. Further gene-diet interactions were reported for, eg, a western dietary pattern with a T2D-GRS, fat and carbohydrate with IRS1 rs2943641, and heme iron with variants of HFE. Physical activity showed interaction with HNF1B, IRS1, PPAR gamma, ADRA2B, SLC2A2, and ABCC8 variants and weight loss interventions with ENPP1, PPAR gamma, ADIPOR2, ADRA2B, TNF alpha, and LIPC variants. However, most findings represent single study findings obtained in European ethnicities. Although some interactions have been reported, their conclusiveness is still low, as most findings were not yet replicated across multiple study populations.}, language = {en} }