TY - JOUR A1 - Plauth, Annabell A1 - Geikowski, Anne A1 - Cichon, Susanne A1 - Wowro, Sylvia J. A1 - Liedgens, Linda A1 - Rousseau, Morten A1 - Weidner, Christopher A1 - Fuhr, Luise A1 - Kliem, Magdalena A1 - Jenkins, Gail A1 - Lotito, Silvina A1 - Wainwright, Linda J. A1 - Sauer, Sascha T1 - Hormetic shifting of redox environment by pro-oxidative resveratrol protects cells against stress JF - Free Radical Biology and Medicine N2 - Resveratrol has gained tremendous interest owing to multiple reported health-beneficial effects. However, the underlying key mechanism of action of this natural product remained largely controversial. Here, we demonstrate that under physiologically relevant conditions major biological effects of resveratrol can be attributed to its generation of oxidation products such as reactive oxygen species (ROS). At low nontoxic concentrations (in general < 50 mu M), treatment with resveratrol increased viability in a set of representative cell models, whereas application of quenchers of ROS completely truncated these beneficial effects. Notably, resveratrol treatment led to mild, Nrf2-specific gene expression reprogramming. For example, in primary epidermal keratinocytes derived from human skin this coordinated process resulted in a 1.3-fold increase of endogenously generated glutathione (GSH) and subsequently in a quantitative reduction of the cellular redox environment by 2.61 mV mmol GSH per g protein. After induction of oxidative stress by using 0.78% (v/v) ethanol, endogenous generation of ROS was consequently reduced by 24% in resveratrol pre-treated cells. In contrast to the common perception that resveratrol acts mainly as a chemical antioxidant or as a target protein-specific ligand, we propose that the cellular response to resveratrol treatment is essentially based on oxidative triggering. In physiological microenvironments this molecular training can lead to hormetic shifting of cellular defense towards a more reductive state to improve physiological resilience to oxidative stress. KW - Trans-reservatrol KW - Hydrogen-peroxide KW - In-vitro KW - Hormesis KW - Ethanol KW - Oxygen KW - Nrf2 KW - Glutathione KW - Metabolism KW - Polyphenols KW - ROS KW - Oxidative stress KW - Redox environment KW - Skin KW - Epidermis Y1 - 2016 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-187186 VL - 99 ER - TY - JOUR A1 - Triphan, Simon M. F. A1 - Jobst, Bertram J. A1 - Anjorin, Angela A1 - Sedlaczek, Oliver A1 - Wolf, Ursula A1 - Terekhov, Maxim A1 - Hoffmann, Christian A1 - Ley, Sebastian A1 - Düber, Christoph A1 - Biederer, Jürgen A1 - Kauczor, Hans-Ulrich A1 - Jakob, Peter M. A1 - Wielpütz, Mark O. T1 - Reproducibility and comparison of oxygen-enhanced T\(_1\) quantification in COPD and asthma patients JF - PLoS ONE N2 - T\(_1\) maps have been shown to yield useful diagnostic information on lung function in patients with chronic obstructive pulmonary disease (COPD) and asthma, both for native T\(_1\) and ΔT\(_1\), the relative reduction while breathing pure oxygen. As parameter quantification is particularly interesting for longitudinal studies, the purpose of this work was both to examine the reproducibility of lung T\(_1\) mapping and to compare T\(_1\) found in COPD and asthma patients using IRSnapShotFLASH embedded in a full MRI protocol. 12 asthma and 12 COPD patients (site 1) and further 15 COPD patients (site 2) were examined on two consecutive days. In each patient, T\(_1\) maps were acquired in 8 single breath-hold slices, breathing first room air, then pure oxygen. Maps were partitioned into 12 regions each to calculate average values. In asthma patients, the average T\(_{1,RA}\) = 1206ms (room air) was reduced to T\(_{1,O2}\) = 1141ms under oxygen conditions (ΔT\(_1\) = 5.3%, p < 5⋅10\(^{−4})\), while in COPD patients both native T\(_{1,RA}\) = 1125ms was significantly shorter (p < 10\(^{−3})\) and the relative reduction to T\(_{1,O2}\) = 1081ms on average ΔT\(_1\) = 4.2%(p < 10\(^{−5}\)). On the second day, with T\(_{1,RA}\) = 1186ms in asthma and T\(_{1,RA}\) = 1097ms in COPD, observed values were slightly shorter on average in all patient groups. ΔT\(_1\) reduction was the least repeatable parameter and varied from day to day by up to 23% in individual asthma and 30% in COPD patients. While for both patient groups T\(_1\) was below the values reported for healthy subjects, the T\(_1\) and ΔT\(_1\) found in asthmatics lies between that of the COPD group and reported values for healthy subjects, suggesting a higher blood volume fraction and better ventilation. However, it could be demonstrated that lung T\(_1\) quantification is subject to notable inter-examination variability, which here can be attributed both to remaining contrast agent from the previous day and the increased dependency of lung T\(_1\) on perfusion and thus current lung state. KW - Medicine KW - Chronic obstrusive pulmonary disease KW - Asthma KW - Oxygen KW - Magnetic resonance imaging KW - Breathing KW - Pulmonary imaging KW - Protons KW - Diagnostic medicine Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-171833 VL - 12 IS - 2 ER - TY - JOUR A1 - Kaireit, Till F. A1 - Sorrentino, Sajoscha A. A1 - Renne, Julius A1 - Schoenfeld, Christian A1 - Voskrebenzev, Andreas A1 - Gutberlet, Marcel A1 - Schulz, Angela A1 - Jakob, Peter M. A1 - Hansen, Gesine A1 - Wacker, Frank A1 - Welte, Tobias A1 - Tümmler, Burkhard A1 - Vogel-Claussen, Jens T1 - Functional lung MRI for regional monitoring of patients with cystic fibrosis JF - PLoS ONE N2 - Purpose To test quantitative functional lung MRI techniques in young adults with cystic fibrosis (CF) compared to healthy volunteers and to monitor immediate treatment effects of a single inhalation of hypertonic saline in comparison to clinical routine pulmonary function tests. Materials and methods Sixteen clinically stable CF patients and 12 healthy volunteers prospectively underwent two functional lung MRI scans and pulmonary function tests before and 2h after a single treatment of inhaled hypertonic saline or without any treatment. MRI-derived oxygen enhanced T1 relaxation measurements, fractional ventilation, first-pass perfusion parameters and a morpho-functional CF-MRI score were acquired. Results Compared to healthy controls functional lung MRI detected and quantified significantly increased ventilation heterogeneity in CF patients. Regional functional lung MRI measures of ventilation and perfusion as well as the CF-MRI score and pulmonary function tests could not detect a significant treatment effect two hours after a single treatment with hypertonic saline in young adults with CF (p>0.05). Conclusion This study shows the feasibility of functional lung MRI as a non-invasive, radiation-free tool for monitoring patients with CF. KW - Physics KW - Magnetic resonance imaging KW - Functional magnetic resonance imaging KW - Cystic fibrosis KW - Oxygen KW - Pulmonary imaging KW - Hypertonic KW - Pulmonary function KW - Quantum chronodynamics Y1 - 2017 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:bvb:20-opus-172457 VL - 12 IS - 12 ER -