TY - JOUR A1 - von Websky, Karoline A1 - Hasan, Ahmed Abdallah Abdalrahman Mohamed A1 - Reichetzeder, Christoph A1 - Tsuprykov, Oleg A1 - Hocher, Berthold T1 - Impact of vitamin D on pregnancy-related disorders and on offspring outcome JF - The Journal of Steroid Biochemistry and Molecular Biology N2 - Observational studies from all over the world continue to find high prevalence rates of vitamin D insufficiency and deficiency in many populations, including pregnant women. Beyond its classical function as a regulator of calcium and phosphate metabolism, vitamin D elicits numerous effects in the human body. Current evidence highlights a vital role of vitamin D in mammalian gestation. During pregnancy, adaptations in maternal vitamin D metabolism lead to a physiologic increase of vitamin D levels, mainly because of an increased renal production, although other potential sources like the placenta are being discussed. A sufficient supply of mother and child with calcium and vitamin D during pregnancy ensures a healthy bone development of the fetus, whereas lack of either of these nutrients can lead to the development of rickets in the child. Moreover, vitamin D insufficiency during pregnancy has consistently been associated with adverse maternal and neonatal pregnancy outcomes. In multitudinous studies, low maternal vitamin D status was associated with a higher risk for pre-eclampsia, gestational diabetes mellitus and other gestational diseases. Likewise, several negative consequences for the fetus have been reported, including fetal growth restriction, increased risk of preterm birth and a changed susceptibility for later-life diseases. However, study results are diverging and causality has not been proven so far. Meta-analyses on the relationship between maternal vitamin D status and pregnancy outcomes revealed a wide heterogeneity of studied populations and the applied methodology in vitamin D assessment. Until today, clinical guidelines for supplementation cannot be based on high-quality evidence and it is not clear if the required intake for pregnant women differs from non-pregnant women. Long-term safety data of vitamin D supplementation in pregnant women has not been established and overdosing of vitamin D might have unfavorable effects, especially in mothers and newborns with mutations of genes involved in vitamin D metabolism. Reliable data from large observational and interventional randomized control trials are urgently needed as a basis for any detailed and safe recommendations for supplementation in the general population and, most importantly, in pregnant women. This is of utmost importance, as ensuring a sufficient vitamin D-supply of mother and child implies a great potential for the prevention of birth complications and development of diseases. KW - Vitamin D deficiency KW - Free vitamin D KW - Vitamin D binding protein KW - Epigenetics KW - DNA methylation KW - Single nucleotide polymorphism KW - Preeclampsia KW - Gestational diabetes mellitus KW - Small for gestational age KW - Long term health Y1 - 2018 U6 - https://doi.org/10.1016/j.jsbmb.2017.11.008 SN - 0960-0760 VL - 180 SP - 51 EP - 64 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Tsuprykov, Oleg A1 - Ando, Ryotaro A1 - Reichetzeder, Christoph A1 - von Websky, Karoline A1 - Antonenko, Viktoriia A1 - Sharkovska, Yuliya A1 - Chaykovska, Lyubov A1 - Rahnenfuehrer, Jan A1 - Hasan, Ahmed Abdallah Abdalrahman Mohamed A1 - Tammen, Harald A1 - Alter, Markus L. A1 - Klein, Thomas A1 - Ueda, Seiji A1 - Yamagishi, Sho-ichi A1 - Okuda, Seiya A1 - Hocher, Berthold T1 - The dipeptidyl peptidase inhibitor linagliptin and the angiotensin II receptor blocker telmisartan show renal benefit by different pathways in rats with 5/6 nephrectomy JF - Kidney international : official journal of the International Society of Nephrology N2 - Dipeptidyl peptidase (DPP)-4 inhibitors delay chronic kidney disease (CKD) progression in experimental diabetic nephropathy in a glucose-independent manner. Here we compared the effects of the DPP-4 inhibitor linagliptin versus telmisartan in preventing CKD progression in non-diabetic rats with 5/6 nephrectomy. Animals were allocated to 1 of 4 groups: sham operated plus placebo; 5/6 nephrectomy plus placebo; 5/6 nephrectomy plus linagliptin; and 5/6 nephrectomy plus telmisartan. Interstitial fibrosis was significantly decreased by 48% with linagliptin but a non-significant 24% with telmisartan versus placebo. The urine albumin-to-creatinine ratio was significantly decreased by 66% with linagliptin and 92% with telmisartan versus placebo. Blood pressure was significantly lowered by telmisartan, but it was not affected by linagliptin. As shown by mass spectrometry, the number of altered peptide signals for linagliptin in plasma was 552 and 320 in the kidney. For telmisartan, there were 108 peptide changes in plasma and 363 in the kidney versus placebo. Linagliptin up-regulated peptides derived from collagen type I, apolipoprotein C1, and heterogeneous nuclear ribonucleoproteins A2/B1, a potential downstream target of atrial natriuretic peptide, whereas telmisartan up-regulated angiotensin II. A second study was conducted to confirm these findings in 5/6 nephrectomy wild-type and genetically deficient DPP-4 rats treated with linagliptin or placebo. Linagliptin therapy in wild-type rats was as effective as DPP-4 genetic deficiency in terms of albuminuria reduction. Thus, linagliptin showed comparable efficacy to telmisartan in preventing CKD progression in non-diabetic rats with 5/6 nephrectomy. However, the underlying pathways seem to be different. Copyright (C) 2016, International Society of Nephrology. Published by Elsevier Inc. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). KW - albuminuria KW - angiotensin receptor blockers KW - chronic kidney disease KW - DPP-4 inhibition KW - proteinuria KW - proteomic analysis Y1 - 2016 U6 - https://doi.org/10.1016/j.kint.2016.01.016 SN - 0085-2538 SN - 1523-1755 VL - 89 SP - 1049 EP - 1061 PB - Nature Publ. Group CY - New York ER - TY - JOUR A1 - Reichetzeder, Christoph A1 - von Websky, Karoline A1 - Tsuprykov, Oleg A1 - Samarin, Azadeh Mohagheghi A1 - Falke, Luise Gabriele A1 - Putra, Sulistyo Emantoko Dwi A1 - Hasan, Ahmed Abdallah Abdalrahman Mohamed A1 - Antonenko, Viktoriia A1 - Curato, Caterina A1 - Rippmann, Joerg A1 - Klein, Thomas A1 - Hocher, Berthold T1 - Head-to-head comparison of structurally unrelated dipeptidyl peptidase 4 inhibitors in the setting of renal ischemia reperfusion injury JF - British journal of pharmacology : journal of The British Pharmacological Society N2 - BACKGROUND AND PURPOSE Results regarding protective effects of dipeptidyl peptidase 4 (DPP4) inhibitors in renal ischaemia-reperfusion injury (IRI) are conflicting. Here we have compared structurally unrelated DPP4 inhibitors in a model of renal IRI. EXPERIMENTAL APPROACH IRI was induced in uninephrectomizedmale rats by renal artery clamping for 30 min. The shamgroup was uninephrectomized but not subjected to IRI. DPP4 inhibitors or vehicle were given p. o. once daily on three consecutive days prior to IRI: linagliptin (1.5 mg.kg(-1).day(-1)), vildagliptin (8mg.kg(-1).day(-1)) and sitagliptin (30 mg.kg(-1).day(-1)). An additional group received sitagliptin until study end (before IRI: 30 mg.kg(-1).day(-1); after IRI: 15mg.kg(-1).day(-1)). KEY RESULTS Plasma-active glucagon-like peptide type 1 (GLP(-1)) increased threefold to fourfold in all DPP4 inhibitor groups 24 h after IRI. Plasma cystatin C, a marker of GFR, peaked 48 h after IRI. Compared with the placebo group, DPP4 inhibition did not reduce increased plasma cystatin C levels. DPP4 inhibitors ameliorated histopathologically assessed tubular damage with varying degrees of drug-specific efficacies. Renal osteopontin expression was uniformly reduced by all DPP4 inhibitors. IRI-related increased renal cytokine expression was not decreased by DPP4 inhibition. Renal DPP4 activity at study end was significantly inhibited in the linagliptin group, but only numerically reduced in the prolonged/dose-adjusted sitagliptin group. Active GLP(-1) plasma levels at study end were increased only in the prolonged/dose-adjusted sitagliptin treatment group. CONCLUSIONS AND IMPLICATIONS In rats with renal IRI, DPP4 inhibition did not alter plasma cystatin C, a marker of glomerular function, but may protect against tubular damage. Y1 - 2017 U6 - https://doi.org/10.1111/bph.13822 SN - 0007-1188 SN - 1476-5381 VL - 174 SP - 2273 EP - 2286 PB - Wiley CY - Hoboken ER - TY - JOUR A1 - Li, Jian A1 - Lu, Yong-Ping A1 - Tsuprykov, Oleg A1 - Hasan, Ahmed Abdallah Abdalrahman Mohamed A1 - Reichetzeder, Christoph A1 - Tian, Mei A1 - Zhang, Xiao Li A1 - Zhang, Qin A1 - Sun, Guo-Ying A1 - Guo, Jingli A1 - Gaballa, Mohamed Mahmoud Salem Ahmed A1 - Peng, Xiao-Ning A1 - Lin, Ge A1 - Hocher, Berthold T1 - Folate treatment of pregnant rat dams abolishes metabolic effects in female offspring induced by a paternal pre-conception unhealthy diet JF - Diabetologia : journal of the European Association for the Study of Diabetes (EASD) N2 - Aims/hypothesis Paternal high-fat diet prior to mating programmes impaired glucose tolerance in female offspring. We examined whether the metabolic consequences in offspring could be abolished by folate treatment of either the male rats before mating or the corresponding female rats during pregnancy. Methods Male F0 rats were fed either control diet or high-fat, high-sucrose and high-salt diet (HFSSD), with or without folate, before mating. Male rats were mated with control-diet-fed dams. After mating, the F0 dams were fed control diet with or without folate during pregnancy. KW - Glucose tolerance KW - High-fat-sucrose-salt diet KW - Maternal folate treatment KW - Paternal programming Y1 - 2018 U6 - https://doi.org/10.1007/s00125-018-4635-x SN - 0012-186X SN - 1432-0428 VL - 61 IS - 8 SP - 1862 EP - 1876 PB - Springer CY - New York ER - TY - JOUR A1 - Hasan, Ahmed Abdallah Abdalrahman Mohamed A1 - von Websky, Karoline A1 - Reichetzeder, Christoph A1 - Tsuprykov, Oleg A1 - Gaballa, Mohamed Mahmoud Salem Ahmed A1 - Guo, Jingli A1 - Zeng, Shufei A1 - Delic, Denis A1 - Tammen, Harald A1 - Klein, Thomas A1 - Kleuser, Burkhard A1 - Hocher, Berthold T1 - Mechanisms of GLP-1 receptor-independent renoprotective effects of the dipeptidyl peptidase type 4 inhibitor linagliptin in GLP-1 receptor knockout mice with 5/6 nephrectomy JF - Kidney international : official journal of the International Society of Nephrology N2 - Dipeptidyl peptidase type 4 (DPP-4) inhibitors were reported to have beneficial effects in experimental models of chronic kidney disease. The underlying mechanisms are not completely understood. However, these effects could be mediated via the glucagon-like peptide-1 (GLP-1)/GLP-1 receptor (GLP1R) pathway. Here we investigated the renal effects of the DPP-4 inhibitor linagliptin in Glp1r-/- knock out and wild-type mice with 5/6 nephrectomy (5/6Nx). Mice were allocated to groups: sham + wild type + placebo; 5/6Nx+ wild type + placebo; 5/6Nx+ wild type + linagliptin; sham + knock out+ placebo; 5/6Nx + knock out+ placebo; 5/6Nx + knock out+ linagliptin. 5/6Nx caused the development of renal interstitial fibrosis, significantly increased plasma cystatin C and creatinine levels and suppressed renal gelatinase/collagenase, matrix metalloproteinase-1 and -13 activities; effects counteracted by linagliptin treatment in wildtype and Glp1r-/- mice. Two hundred ninety-eight proteomics signals were differentially regulated in kidneys among the groups, with 150 signals specific to linagliptin treatment as shown by mass spectrometry. Treatment significantly upregulated three peptides derived from collagen alpha-1(I), thymosin beta 4 and heterogeneous nuclear ribonucleoprotein Al (HNRNPA1) and significantly downregulated one peptide derived from Y box binding protein-1 (YB-1). The proteomics results were further confirmed using western blot and immunofluorescence microscopy. Also, 5/6Nx led to significant up-regulation of renal transforming growth factor-beta 1 and pSMAD3 expression in wild type mice and linagliptin significantly counteracted this up-regulation in wild type and GIplr-/- mice. Thus, the renoprotective effects of linagliptin cannot solely be attributed to the GLP-1/GLP1R pathway, highlighting the importance of other signaling pathways (collagen I homeostasis, HNRNPA1,YB-1,thymosin beta 4 and TGF-beta 1) influenced by DPP-4 inhibition. KW - chronic kidney disease KW - collagen I KW - fibrosis KW - Glp1r(-/-) mice KW - HNRNPA1 KW - linagliptin KW - proteomic analysis KW - TGF-beta 1 KW - thymosin beta 4 KW - YB-1 Y1 - 2019 U6 - https://doi.org/10.1016/j.kint.2019.01.010 SN - 0085-2538 SN - 1523-1755 VL - 95 IS - 6 SP - 1373 EP - 1388 PB - Elsevier CY - New York ER - TY - JOUR A1 - Hasan, Ahmed Abdallah Abdalrahman Mohamed A1 - Hocher, Berthold T1 - Role of soluble and membrane-bound dipeptidyl peptidase-4 in diabetic nephropathy JF - Journal of Molecular Endocrinology N2 - Diabetic nephropathy is one of the most frequent, devastating and costly complications of diabetes. The available therapeutic approaches are limited. Dipeptidyl peptidase type 4 (DPP-4) inhibitors represent a new class of glucose-lowering drugs that might also have reno-protective properties. DPP-4 exists in two forms: a plasma membranebound form and a soluble form, and can exert many biological actions mainly through its peptidase activity and interaction with extracellular matrix components. The kidneys have the highest DPP-4 expression level in mammalians. DPP-4 expression and urinary activity are up-regulated in diabetic nephropathy, highlighting its role as a potential target to manage diabetic nephropathy. Preclinical animal studies and some clinical data suggest that DPP-4 inhibitors decrease the progression of diabetic nephropathy in a blood pressure-and glucose-independent manner. Many studies reported that these reno-protective effects could be due to increased half-life of DPP-4 substrates such as glucagon-like peptide-1 (GLP-1) and stromal derived factor-1 alpha (SDF-1a). However, the underlying mechanisms are far from being completely understood and clearly need further investigations. KW - DPP-4 KW - diabetic nephropathy KW - DPP-4 inhibitors KW - GLP-1 and SDF-1a Y1 - 2017 U6 - https://doi.org/10.1530/JME-17-0005 SN - 0952-5041 SN - 1479-6813 VL - 59 SP - R1 EP - R10 PB - Bioscientifica LTD CY - Bristol ER - TY - THES A1 - Hasan, Ahmed Abdallah Abdalrahman Mohamed T1 - GLP-1 receptor-independent mechanisms of DPP-4 inhibition on renal disease progression T2 - GLP-1 Rezeptor-unabhängige Mechanismen von DPP-4 Hemmung bei der Fortschreitung der Nierenerkrankung Y1 - 2018 ER - TY - JOUR A1 - Glosse, Philipp A1 - Feger, Martina A1 - Mutig, Kerim A1 - Chen, Hong A1 - Hirche, Frank A1 - Hasan, Ahmed Abdallah Abdalrahman Mohamed A1 - Gaballa, Mohamed Mahmoud Salem Ahmed A1 - Hocher, Berthold A1 - Lang, Florian A1 - Föller, Michael T1 - AMP-activated kinase is a regulator of fibroblast growth factor 23 production JF - Kidney international : official journal of the International Society of Nephrology N2 - Fibroblast growth factor 23 (FGF23) is a proteohormone regulating renal phosphate transport and vitamin D metabolism as well as inducing left heart hypertrophy. FGF23-deficient mice suffer from severe tissue calcification, accelerated aging and a myriad of aging-associated diseases. Bone cells produce FGF23 upon store-operated calcium ion entry (SOCE) through the calcium selective ion channel Orai1. AMP-activated kinase (AMPK) is a powerful energy sensor helping cells survive states of energy deficiency, and AMPK down-regulates Orai1. Here we investigated the role of AMPK in FGF23 production. Fgf23 gene transcription was analyzed by qRT-PCR and SOCE by fluorescence optics in UMR106 osteoblast-like cells while the serum FGF23 concentration and phosphate metabolism were assessed in AMPKa1-knockout and wild-type mice. The AMPK activator, 5-aminoimidazole-4-carboxamide ribonucleotide (AICAR) down-regulated, whereas the AMPK inhibitor, dorsomorphin dihydrochloride (compound C) and AMPK gene silencing induced Fgf23 transcription. AICAR decreased membrane abundance of Orai1 and SOCE. SOCE inhibitors lowered Fgf23 gene expression induced by AMPK inhibition. AMPKa1-knockout mice had a higher serum FGF23 concentration compared to wild-type mice. Thus, AMPK participates in the regulation of FGF23 production in vitro and in vivo. The inhibitory effect of AMPK on FGF23 production is at least in part mediated by Orai1-involving SOCE. KW - calcium KW - FGF23 KW - Klotho KW - Orai1 KW - phosphate KW - parathyroid hormone Y1 - 2018 U6 - https://doi.org/10.1016/j.kint.2018.03.006 SN - 0085-2538 SN - 1523-1755 VL - 94 IS - 3 SP - 491 EP - 501 PB - Elsevier CY - New York ER - TY - GEN A1 - Dwi Putra, Sulistyo Emantoko A1 - Reichetzeder, Christoph A1 - Hasan, Ahmed Abdallah Abdalrahman Mohamed A1 - Slowinski, Torsten A1 - Chu, Chang A1 - Krämer, Bernhard K. A1 - Kleuser, Burkhard A1 - Hocher, Berthold T1 - Being born large for gestational age is associated with increased global placental DNA methylation T2 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - Being born small (SGA) or large for gestational age (LGA) is associated with adverse birth outcomes and metabolic diseases in later life of the offspring. It is known that aberrations in growth during gestation are related to altered placental function. Placental function is regulated by epigenetic mechanisms such as DNA methylation. Several studies in recent years have demonstrated associations between altered patterns of DNA methylation and adverse birth outcomes. However, larger studies that reliably investigated global DNA methylation are lacking. The aim of this study was to characterize global placental DNA methylation in relationship to size for gestational age. Global DNA methylation was assessed in 1023 placental samples by LC-MS/MS. LGA offspring displayed significantly higher global placental DNA methylation compared to appropriate for gestational age (AGA; p<0.001). ANCOVA analyses adjusted for known factors impacting on DNA methylation demonstrated an independent association between placental global DNA methylation and LGA births (p<0.001). Tertile stratification according to global placental DNA methylation levels revealed a significantly higher frequency of LGA births in the third tertile. Furthermore, a multiple logistic regression analysis corrected for known factors influencing birth weight highlighted an independent positive association between global placental DNA methylation and the frequency of LGA births (p=0.001). T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1405 KW - fetal origins hypothesis KW - birth weight KW - repetitive elements KW - glucocorticoid receptor KW - nutrient transport KW - growth restriction KW - later health KW - pregnancy KW - genes KW - patterns Y1 - 2020 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-516289 SN - 1866-8372 IS - 1 ER - TY - JOUR A1 - Dwi Putra, Sulistyo Emantoko A1 - Reichetzeder, Christoph A1 - Hasan, Ahmed Abdallah Abdalrahman Mohamed A1 - Slowinski, Torsten A1 - Chu, Chang A1 - Krämer, Bernhard K. A1 - Kleuser, Burkhard A1 - Hocher, Berthold T1 - Being born large for gestational age is associated with increased global placental DNA methylation JF - Scientific Reports N2 - Being born small (SGA) or large for gestational age (LGA) is associated with adverse birth outcomes and metabolic diseases in later life of the offspring. It is known that aberrations in growth during gestation are related to altered placental function. Placental function is regulated by epigenetic mechanisms such as DNA methylation. Several studies in recent years have demonstrated associations between altered patterns of DNA methylation and adverse birth outcomes. However, larger studies that reliably investigated global DNA methylation are lacking. The aim of this study was to characterize global placental DNA methylation in relationship to size for gestational age. Global DNA methylation was assessed in 1023 placental samples by LC-MS/MS. LGA offspring displayed significantly higher global placental DNA methylation compared to appropriate for gestational age (AGA; p<0.001). ANCOVA analyses adjusted for known factors impacting on DNA methylation demonstrated an independent association between placental global DNA methylation and LGA births (p<0.001). Tertile stratification according to global placental DNA methylation levels revealed a significantly higher frequency of LGA births in the third tertile. Furthermore, a multiple logistic regression analysis corrected for known factors influencing birth weight highlighted an independent positive association between global placental DNA methylation and the frequency of LGA births (p=0.001). KW - fetal origins hypothesis KW - birth weight KW - repetitive elements KW - glucocorticoid receptor KW - nutrient transport KW - growth restriction KW - later health KW - pregnancy KW - genes KW - patterns Y1 - 2020 U6 - https://doi.org/10.1038/s41598-020-57725-0 SN - 2045-2322 VL - 10 IS - 1 SP - 1 EP - 10 PB - Springer Nature CY - London ER -