@article{PlauthGeikowskiCichonetal.2016, author = {Plauth, Annabell and Geikowski, Anne and Cichon, Susanne and Wowro, Sylvia J. and Liedgens, Linda and Rousseau, Morten and Weidner, Christopher and Fuhr, Luise and Kliem, Magdalena and Jenkins, Gail and Lotito, Silvina and Wainwright, Linda J. and Sauer, Sascha}, title = {Hormetic shifting of redox environment by pro-oxidative resveratrol protects cells against stress}, series = {Free Radical Biology and Medicine}, volume = {99}, journal = {Free Radical Biology and Medicine}, doi = {10.1016/j.freeradbiomed.2016.08.006}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-187186}, pages = {608-622}, year = {2016}, abstract = {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.}, language = {en} } @article{YoussifHaggagElshamyetal.2019, author = {Youssif, Khayrya A. and Haggag, Eman G. and Elshamy, Ali M. and Rabeh, Mohamed A. and Gabr, Nagwan M. and Seleem, Amany and Salem, M. Alaraby and Hussein, Ahmed S. and Krischke, Markus and Mueller, Martin J. and Ramadan Abdelmohsen, Usama}, title = {Anti-Alzheimer potential, metabolomic profiling and molecular docking of green synthesized silver nanoparticles of Lampranthus coccineus and Malephora lutea aqueous extracts}, series = {PLoS ONE}, volume = {14}, journal = {PLoS ONE}, number = {11}, doi = {10.1371/journal.pone.0223781}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-202696}, pages = {e0223781}, year = {2019}, abstract = {The green synthesis of silver nanoparticles (SNPs) using plant extracts is an eco-friendly method. It is a single step and offers several advantages such as time reducing, cost-effective and environmental non-toxic. Silver nanoparticles are a type of Noble metal nanoparticles and it has tremendous applications in the field of diagnostics, therapeutics, antimicrobial activity, anticancer and neurodegenerative diseases. In the present work, the aqueous extracts of aerial parts of Lampranthus coccineus and Malephora lutea F. Aizoaceae were successfully used for the synthesis of silver nanoparticles. The formation of silver nanoparticles was early detected by a color change from pale yellow to reddish-brown color and was further confirmed by transmission electron microscope (TEM), UV-visible spectroscopy, Fourier transform infrared (FTIR) spectroscopy, dynamic light scattering (DLS), X-ray diffraction (XRD), and energy-dispersive X-ray diffraction (EDX). The TEM analysis of showed spherical nanoparticles with a mean size between 12.86 nm and 28.19 nm and the UV- visible spectroscopy showed λ\(_{max}\) of 417 nm, which confirms the presence of nanoparticles. The neuroprotective potential of SNPs was evaluated by assessing the antioxidant and cholinesterase inhibitory activity. Metabolomic profiling was performed on methanolic extracts of L. coccineus and M. lutea and resulted in the identification of 12 compounds, then docking was performed to investigate the possible interaction between the identified compounds and human acetylcholinesterase, butyrylcholinesterase, and glutathione transferase receptor, which are associated with the progress of Alzheimer's disease. Overall our SNPs highlighted its promising potential in terms of anticholinesterase and antioxidant activity as plant-based anti-Alzheimer drug and against oxidative stress.}, language = {en} }