@article{VieraElMerahbiNieswandtetal.2016, author = {Viera, Jonathan Trujillo and El-Merahbi, Rabih and Nieswandt, Bernhard and Stegner, David and Sumara, Grzegorz}, title = {Phospholipases D1 and D2 Suppress Appetite and Protect against Overweight}, series = {PLoS ONE}, volume = {11}, journal = {PLoS ONE}, number = {6}, doi = {10.1371/journal.pone.0157607}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-179729}, year = {2016}, abstract = {Obesity is a major risk factor predisposing to the development of peripheral insulin resistance and type 2 diabetes (T2D). Elevated food intake and/or decreased energy expenditure promotes body weight gain and acquisition of adipose tissue. Number of studies implicated phospholipase D (PLD) enzymes and their product, phosphatidic acid (PA), in regulation of signaling cascades controlling energy intake, energy dissipation and metabolic homeostasis. However, the impact of PLD enzymes on regulation of metabolism has not been directly determined so far. In this study we utilized mice deficient for two major PLD isoforms, PLD1 and PLD2, to assess the impact of these enzymes on regulation of metabolic homeostasis. We showed that mice lacking PLD1 or PLD2 consume more food than corresponding control animals. Moreover, mice deficient for PLD2, but not PLD1, present reduced energy expenditure. In addition, deletion of either of the PLD enzymes resulted in development of elevated body weight and increased adipose tissue content in aged animals. Consistent with the fact that elevated content of adipose tissue predisposes to the development of hyperlipidemia and insulin resistance, characteristic for the pre-diabetic state, we observed that Pld1\(^{-/-}\) and Pld2\(^{-/-}\) mice present elevated free fatty acids (FFA) levels and are insulin as well as glucose intolerant. In conclusion, our data suggest that deficiency of PLD1 or PLD2 activity promotes development of overweight and diabetes.}, language = {en} } @phdthesis{Marker2020, author = {Marker, Caroline}, title = {On a meta-level: Contributions of meta-analytic summaries in media psychological research}, doi = {10.25972/OPUS-20917}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-209173}, school = {Universit{\"a}t W{\"u}rzburg}, year = {2020}, abstract = {The rising use of new media has given rise to public discussions about their possible negative consequences. The social sciences have answered these concerns, providing many studies investigating different media types (e.g., social media, video games) and different related variables (e.g., psychological well-being, academic achievement). Within this big body of research, some research results have confirmed negative associations with frequent media use; other studies have found no or even positive relationships. With heterogeneous results, it is difficult to obtain a clear picture of the relationships and causalities of new media. The method of meta-analysis allows a synthesis of all existing data, providing an overall effect size as well as moderator and mediator analyses which might explain the heterogeneity. Three manuscripts present meta-analytic evidence related to a) the relationship between social media use and academic achievement, b) the relationship between video gaming and overweight, and c) the relationship between social media and psychological correlates. Manuscript \#1 found small relationships which depend on the usage pattern of social media. The relationship is positive, as long as social media use is related to school. Manuscript \#2 showed that children's and adolescents' video gaming is independent from their body mass, while adults who play more have a higher body mass. Manuscript \#3 summarized existing meta-analytic evidence that links social media with psychological wellbeing, academic achievement, and narcissism with small to moderate effect sizes. All three manuscripts underscore the potential of meta-analyses to synthesize previous research and to identify moderators. Although meta-analyses are not necessarily superior to other approaches because of their limitations (e.g. limited information or quality of primary studies) they are very promising for media psychology. Meta-analyses can reduce complexity and might be helpful for the communication of research results to the general public.}, subject = {Medienkonsum}, language = {en} } @article{JurowichOttoRikkalaetal.2015, author = {Jurowich, Christian Ferdinand and Otto, Christoph and Rikkala, Prashanth Reddy and Wagner, Nicole and Vrhovac, Ivana and Sabolić, Ivan and Germer, Christoph-Thomas and Koepsell, Hermann}, title = {Ileal interposition in rats with experimental type 2 like diabetes improves glycemic control independently of glucose absorption}, series = {Journal of Diabetes Research}, volume = {2015}, journal = {Journal of Diabetes Research}, number = {490365}, doi = {10.1155/2015/490365}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-149166}, year = {2015}, abstract = {Bariatric operations in obese patients with type 2 diabetes often improve diabetes before weight loss is observed. In patients mainly Roux-en-Y-gastric bypass with partial stomach resection is performed. Duodenojejunal bypass (DJB) and ileal interposition (IIP) are employed in animal experiments. Due to increased glucose exposition of L-cells located in distal ileum, all bariatric surgery procedures lead to higher secretion of antidiabetic glucagon like peptide-1 (GLP-1) after glucose gavage. After DJB also downregulation of Na\(^{+}\)-D-glucose cotransporter SGLT1 was observed. This suggested a direct contribution of decreased glucose absorption to the antidiabetic effect of bariatric surgery. To investigate whether glucose absorption is also decreased after IIP, we induced diabetes with decreased glucose tolerance and insulin sensitivity in male rats and investigated effects of IIP on diabetes and SGLT1. After IIP, we observed weight-independent improvement of glucose tolerance, increased insulin sensitivity, and increased plasma GLP-1 after glucose gavage. The interposed ileum was increased in diameter and showed increased length of villi, hyperplasia of the epithelial layer, and increased number of L-cells. The amount of SGLT1-mediated glucose uptake in interposed ileum was increased 2-fold reaching the same level as in jejunum. Thus, improvement of glycemic control by bariatric surgery does not require decreased glucose absorption.}, language = {en} } @article{NordbeckBoenhofHilleretal.2013, author = {Nordbeck, Peter and B{\"o}nhof, Leoni and Hiller, Karl-Heinz and Voll, Sabine and Arias-Loza, Paula and Seidlmaier, Lea and Williams, Tatjana and Ye, Yu-Xiang and Gensler, Daniel and Pelzer, Theo and Ertl, Georg and Jakob, Peter M. and Bauer, Wolfgang R. and Ritter, Oliver}, title = {Impact of Thoracic Surgery on Cardiac Morphology and Function in Small Animal Models of Heart Disease: A Cardiac MRI Study in Rats}, series = {PLoS ONE}, volume = {8}, journal = {PLoS ONE}, number = {8}, doi = {10.1371/journal.pone.0068275}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-130064}, pages = {e68275}, year = {2013}, abstract = {Background Surgical procedures in small animal models of heart disease might evoke alterations in cardiac morphology and function. The aim of this study was to reveal and quantify such potential artificial early or long term effects in vivo, which might account for a significant bias in basic cardiovascular research, and, therefore, could potentially question the meaning of respective studies. Methods Female Wistar rats (n = 6 per group) were matched for weight and assorted for sham left coronary artery ligation or control. Cardiac morphology and function was then investigated in vivo by cine magnetic resonance imaging at 7 Tesla 1 and 8 weeks after the surgical procedure. The time course of metabolic and inflammatory blood parameters was determined in addition. Results Compared to healthy controls, rats after sham surgery showed a lower body weight both 1 week (267.5±10.6 vs. 317.0±11.3 g, n<0.05) and 8 weeks (317.0±21.1 vs. 358.7±22.4 g, n<0.05) after the intervention. Left and right ventricular morphology and function were not different in absolute measures in both groups 1 week after surgery. However, there was a confined difference in several cardiac parameters normalized to the body weight (bw), such as myocardial mass (2.19±0.30/0.83±0.13 vs. 1.85±0.22/0.70±0.07 mg left/right per g bw, p<0.05), or enddiastolic ventricular volume (1.31±0.36/1.21±0.31 vs. 1.14±0.20/1.07±0.17 µl left/right per g bw, p<0.05). Vice versa, after 8 weeks, cardiac masses, volumes, and output showed a trend for lower values in sham operated rats compared to controls in absolute measures (782.2±57.2/260.2±33.2 vs. 805.9±84.8/310.4±48.5 mg, p<0.05 for left/right ventricular mass), but not normalized to body weight. Matching these findings, blood testing revealed only minor inflammatory but prolonged metabolic changes after surgery not related to cardiac disease. Conclusion Cardio-thoracic surgical procedures in experimental myocardial infarction cause distinct alterations upon the global integrity of the organism, which in the long term also induce circumscribed repercussions on cardiac morphology and function. This impact has to be considered when analyzing data from respective animal studies and transferring these findings to conditions in patients.}, language = {en} } @article{HeldMittnachtKolbetal.2014, author = {Held, Matthias and Mittnacht, Maria and Kolb, Martin and Karl, Sabine and Jany, Berthold}, title = {Pulmonary and Cardiac Function in Asymptomatic Obese Subjects and Changes following a Structured Weight Reduction Program: A Prospective Observational Study}, series = {PLOS ONE}, volume = {9}, journal = {PLOS ONE}, number = {9}, doi = {10.1371/journal.pone.0107480}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-119239}, pages = {e107480}, year = {2014}, abstract = {Background The prevalence of obesity is rising. Obesity can lead to cardiovascular and ventilatory complications through multiple mechanisms. Cardiac and pulmonary function in asymptomatic subjects and the effect of structured dietary programs on cardiac and pulmonary function is unclear. Objective To determine lung and cardiac function in asymptomatic obese adults and to evaluate whether weight loss positively affects functional parameters. Methods We prospectively evaluated bodyplethysmographic and echocardiographic data in asymptomatic subjects undergoing a structured one-year weight reduction program. Results 74 subjects (32 male, 42 female; mean age 42±12 years) with an average BMI 42.5±7.9, body weight 123.7±24.9 kg were enrolled. Body weight correlated negatively with vital capacity (R = -0.42, p<0.001), FEV1 (R = -0.497, p<0.001) and positively with P 0.1 (R = 0.32, p = 0.02) and myocardial mass (R = 0.419, p = 0.002). After 4 months the study subjects had significantly reduced their body weight (-26.0±11.8 kg) and BMI (-8.9±3.8) associated with a significant improvement of lung function (absolute changes: vital capacity +5.5±7.5\% pred., p<0.001; FEV1+9.8±8.3\% pred., p<0.001, ITGV+16.4±16.0\% pred., p<0.001, SR tot -17.4±41.5\% pred., p<0.01). Moreover, P0.1/Pimax decreased to 47.7\% (p<0.01) indicating a decreased respiratory load. The change of FEV1 correlated significantly with the change of body weight (R = -0.31, p = 0.03). Echocardiography demonstrated reduced myocardial wall thickness (-0.08±0.2 cm, p = 0.02) and improved left ventricular myocardial performance index (-0.16±0.35, p = 0.02). Mitral annular plane systolic excursion (+0.14, p = 0.03) and pulmonary outflow acceleration time (AT +26.65±41.3 ms, p = 0.001) increased. Conclusion Even in asymptomatic individuals obesity is associated with abnormalities in pulmonary and cardiac function and increased myocardial mass. All the abnormalities can be reversed by a weight reduction program.}, language = {en} } @article{ZinmanInzucchiLachinetal.2014, author = {Zinman, Bernard and Inzucchi, Silvio E. and Lachin, John M. and Wanner, Christoph and Ferrari, Roberto and Fitchett, David and Bluhmki, Erich and Hantel, Stefan and Kempthorne-Rawson, Joan and Newman, Jennifer and Johansen, Odd Erik and Woerle, Hans-Juergen and Broedl, Uli C.}, title = {Rationale, design, and baseline characteristics of a randomized, placebo-controlled cardiovascular outcome trial of empagliflozin (EMPA-REG OUTCOME (TM))}, series = {Cardiovascular Diabetology}, volume = {13}, journal = {Cardiovascular Diabetology}, number = {102}, issn = {1475-2840}, doi = {10.1186/1475-2840-13-102}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-116036}, year = {2014}, abstract = {Background: Evidence concerning the importance of glucose lowering in the prevention of cardiovascular (CV) outcomes remains controversial. Given the multi-faceted pathogenesis of atherosclerosis in diabetes, it is likely that any intervention to mitigate this risk must address CV risk factors beyond glycemia alone. The SGLT-2 inhibitor empagliflozin improves glucose control, body weight and blood pressure when used as monotherapy or add-on to other antihyperglycemic agents in patients with type 2 diabetes. The aim of the ongoing EMPA-REG OUTCOME (TM) trial is to determine the long-term CV safety of empagliflozin, as well as investigating potential benefits on macro-/microvascular outcomes. Methods: Patients who were drug naive (HbA(1c) >= 7.0\% and <= 9.0\%), or on background glucose-lowering therapy (HbA(1c) >= 7.0\% and <= 10.0\%), and were at high risk of CV events, were randomized (1:1:1) and treated with empagliflozin 10 mg, empagliflozin 25 mg, or placebo (double blind, double dummy) superimposed upon the standard of care. The primary outcome is time to first occurrence of CV death, non-fatal myocardial infarction, or non-fatal stroke. CV events will be prospectively adjudicated by an independent Clinical Events Committee. The trial will continue until >= 691 confirmed primary outcome events have occurred, providing a power of 90\% to yield an upper limit of the adjusted 95\% CI for a hazard ratio of <1.3 with a one-sided a of 0.025, assuming equal risks between placebo and empagliflozin (both doses pooled). Hierarchical testing for superiority will follow for the primary outcome and key secondary outcomes (time to first occurrence of CV death, non-fatal myocardial infarction, non-fatal stroke or hospitalization for unstable angina pectoris) where non-inferiority is achieved. Results: Between Sept 2010 and April 2013, 592 clinical sites randomized and treated 7034 patients (41\% from Europe, 20\% from North America, and 19\% from Asia). At baseline, the mean age was 63 +/- 9 years, BMI 30.6 +/- 5.3 kg/m(2), HbA1c 8.1 +/- 0.8\%, and eGFR 74 +/- 21 ml/min/1.73 m(2). The study is expected to report in 2015. Discussion: EMPA REG OUTCOME (TM) will determine the CV safety of empagliflozin in a cohort of patients with type 2 diabetes and high CV risk, with the potential to show cardioprotection.}, language = {en} }