Plasma medicine is gaining increasing attention and is moving from basic research into clinical practice. While areas of application are diverse, much research has been conducted assessing the use of cold atmospheric pressure plasma (CAP) in wound healing and cancer treatment—two applications with entirely different goals. In wound healing, a tissue-stimulating effect is intended, whereas cancer therapy aims at killing malignant cells. In this review, we provide an overview of the latest clinical and some preclinical research on the efficacy of CAP in wound healing and cancer therapy. Furthermore, we discuss the current understanding of molecular signaling mechanisms triggered by CAP that grant CAP its antiseptic and tissue regenerating or anti-proliferative and cell death-inducing properties. For the efficacy of CAP in wound healing, already substantial evidence from clinical studies is available, while evidence for therapeutic effects of CAP in oncology is mainly from in vitro and in vivo animal studies. Efforts to elucidate the mode of action of CAP suggest that different components, such as ultraviolet (UV) radiation, electromagnetic fields, and reactive species, may act synergistically, with reactive species being regarded as the major effector by modulating complex and concentration-dependent redox signaling pathways.

Due to the weak regeneration potential of cartilage, there is a high clinical incidence of articular joint disease, leading to a strong demand for cartilaginous tissue surrogates. The aim of this study was to evaluate a gelatin-based hydrogel for its suitability to support chondrogenic differentiation of human mesenchymal stem cells. Gelatin-based hydrogels are biodegradable, show high biocompatibility, and offer possibilities to introduce functional groups and/or ligands. In order to prove their chondrogenesis-supporting potential, a hydrogel film was developed and compared with standard cell culture polystyrene regarding the differentiation behavior of human mesenchymal stem cells. Cellular basis for this study were human adipose tissue-derived mesenchymal stem cells, which exhibit differentiation potential along the adipogenic, osteogenic and chondrogenic lineage. The results obtained show a promotive effect of gelatin-based hydrogels on chondrogenic differentiation of mesenchymal stem cells in vitro and therefore encourage subsequent in vivo studies.

Particulate matter is associated with different human diseases affecting organs such as the respiratory and cardiovascular systems. Very small particles (nanoparticles) have been shown to be rapidly internalized into the body. Since the sites of internalization and the location of the detected particles are often far apart, a distribution via the blood stream must have occurred. Thus, endothelial cells, which line the inner surface of blood vessels, must have had direct contact with the particles. In this study we tested the effects of metallic nanoparticles (Co and Ni) on oxidative stress and proinflammatory response in human endothelial cells in vitro. Exposure to both nanoparticle types led to a concentration-dependent cytotoxic effect. However, the effects on oxidative stress and pro-inflammatory response differed dramatically. Due to the nanoparticle-induced effects, a comparison between metallic nanoparticle- and metal ion-treatment with the corresponding ions was made. Again, divergent effects of nanoparticles compared with the ions were observed, thus indicating differences in the signaling pathways induced by these compounds. These paradoxical responses to different metallic nanoparticles and ions demonstrate the complexity of nanoparticle-induced effects and suggest the need to design new strategies for nanoparticle toxicology.

Metals play a crucial role in the human body, especially as ions in metalloproteins. Essential metals, such as calcium, iron, and zinc are crucial for various physiological functions, but their interactions within biological networks are complex and not fully understood. Mesenchymal stem/stromal cells (MSCs) are essential for tissue regeneration due to their ability to differentiate into various cell types. This review article addresses the effects of physiological and unphysiological, but not directly toxic, metal ion concentrations, particularly concerning MSCs. Overloading or unbalancing of metal ion concentrations can significantly impair the function and differentiation capacity of MSCs. In addition, excessive or unbalanced metal ion concentrations can lead to oxidative stress, which can affect viability or inflammation. Data on the effects of metal ions on MSC differentiation are limited and often contradictory. Future research should, therefore, aim to clarify the mechanisms by which metal ions affect MSC differentiation, focusing on aspects such as metal ion interactions, ion concentrations, exposure duration, and other environmental conditions. Understanding these interactions could ultimately improve the design of biomaterials and implants to promote MSC-mediated tissue regeneration. It could also lead to the development of innovative therapeutic strategies in regenerative medicine.

In this study the influence of cultivation and proliferation on energy metabolic characteristics of human umbilical vein endothelial cells (HUVEC) has been examined. The energy metabolic capacities of human endothelial cells freshly isolated from the umbilical vein were compared with those after cultivation for three passages and as subconfluent and confluent cultures. Expression of cell type-specific differentiation markers and proliferative activity were studied in dependency on cultivation characteristics. Furthermore, the energy metabolic characteristics of HUVEC were analyzed by measurement of the maximum catalytic activities of marker enzymes of various metabolic pathways. Examination of a typical marker of proliferation, Ki67, confirmed that HUVEC changed in culture from a non-proliferative to a proliferative state. Compared to other cell types, the enzyme pattern of HUVEC showed a high glycolytic and a high NADPH regenerating capacity. These capacities increased by cultivation nearly to the same degree as marker enzymes of other metabolic pathways (e.g. citric acid cycle). Our data support the theory that metabolism of EC is primarily by "aerobic glycolysis", i.e. the conversion of glucose to lactate in the presence of oxygen. These characteristics were independent of whether the cells are freshly isolated/non-proliferating or cell culture-adapted/proliferating.