@article{LaegerCastanoMartinezWernoetal.2018, author = {Laeger, Thomas and Castano-Martinez, Teresa and Werno, Martin W. and Japtok, Lukasz and Baumeier, Christian and Jonas, Wenke and Kleuser, Burkhard and Sch{\"u}rmann, Annette}, title = {Dietary carbohydrates impair the protective effect of protein restriction against diabetes in NZO mice used as a model of type 2 diabetes}, series = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, volume = {61}, journal = {Diabetologia : journal of the European Association for the Study of Diabetes (EASD)}, number = {6}, publisher = {Springer}, address = {New York}, issn = {0012-186X}, doi = {10.1007/s00125-018-4595-1}, pages = {1459 -- 1469}, year = {2018}, abstract = {Aims/hypothesis Low-protein diets are well known to improve glucose tolerance and increase energy expenditure. Increases in circulating fibroblast growth factor 21 (FGF21) have been implicated as a potential underlying mechanism. Methods We aimed to test whether low-protein diets in the context of a high-carbohydrate or high-fat regimen would also protect against type 2 diabetes in New Zealand Obese (NZO) mice used as a model of polygenetic obesity and type 2 diabetes. Mice were placed on high-fat diets that provided protein at control (16 kJ\%; CON) or low (4 kJ\%; low-protein/high-carbohydrate [LP/HC] or low-protein/high-fat [LP/HF]) levels. Results Protein restriction prevented the onset of hyperglycaemia and beta cell loss despite increased food intake and fat mass. The effect was seen only under conditions of a lower carbohydrate/fat ratio (LP/HF). When the carbohydrate/fat ratio was high (LP/HC), mice developed type 2 diabetes despite the robustly elevated hepatic FGF21 secretion and increased energy expenditure. Conclusion/interpretation Prevention of type 2 diabetes through protein restriction, without lowering food intake and body fat mass, is compromised by high dietary carbohydrates. Increased FGF21 levels and elevated energy expenditure do not protect against hyperglycaemia and type 2 diabetes per se.}, language = {en} } @article{JonasKluthHelmsetal.2022, author = {Jonas, Wenke and Kluth, Oliver and Helms, Anett and Voss, Sarah and Jahnert, Markus and Gottmann, Pascal and Speckmann, Thilo and Knebel, Birgit and Chadt, Alexandra and Al-Hasani, Hadi and Sch{\"u}rmann, Annette and Vogel, Heike}, title = {Identification of novel genes involved in hyperglycemia in mice}, series = {International journal of molecular sciences}, volume = {23}, journal = {International journal of molecular sciences}, number = {6}, publisher = {MDPI}, address = {Basel}, issn = {1661-6596}, doi = {10.3390/ijms23063205}, pages = {13}, year = {2022}, abstract = {Current attempts to prevent and manage type 2 diabetes have been moderately effective, and a better understanding of the molecular roots of this complex disease is important to develop more successful and precise treatment options. Recently, we initiated the collective diabetes cross, where four mouse inbred strains differing in their diabetes susceptibility were crossed with the obese and diabetes-prone NZO strain and identified the quantitative trait loci (QTL) Nidd13/NZO, a genomic region on chromosome 13 that correlates with hyperglycemia in NZO allele carriers compared to B6 controls. Subsequent analysis of the critical region, harboring 644 genes, included expression studies in pancreatic islets of congenic Nidd13/NZO mice, integration of single-cell data from parental NZO and B6 islets as well as haplotype analysis. Finally, of the five genes (Acot12, S100z, Ankrd55, Rnf180, and Iqgap2) within the polymorphic haplotype block that are differently expressed in islets of B6 compared to NZO mice, we identified the calcium-binding protein S100z gene to affect islet cell proliferation as well as apoptosis when overexpressed in MINE cells. In summary, we define S100z as the most striking gene to be causal for the diabetes QTL Nidd13/NZO by affecting beta-cell proliferation and apoptosis. Thus, S100z is an entirely novel diabetes gene regulating islet cell function.}, language = {en} }