Stem cell-based therapy represents a promising approach for the treatment of numerous currently uncurable diseases. However, wider application of this therapy is still bound by various limitations. To increase the effectiveness of cell therapy, a combined application of stem cells with various types of chemicals or agents, which could support the immunoregulatory and therapeutic properties of stem cells, has been proposed and tested. One prospective approach is offered by the co-application of mesenchymal stem cells (MSCs), which have potent immunomodulatory and regenerative properties, and selected metal nanoparticles (NPs) which have been used in various fields of medicine for their immunomodulatory, anti-oxidant and antibacterial properties. It has been shown that the main mechanism of the therapeutic action of MSCs is the production of immunomodulatory molecules and growth factors, and that the secretory activity of MSCs can be modified by different types of NPs. For this purpose, metal NPs are extremely useful. They possess unique characteristics and can influence the growth and repair of tissues, exert strong antimicrobial activity and serve as nanocarriers. Thus, treatment based on the simultaneous application of MSCs and selected NPs combines the therapeutic effects of MSCs and impacts of NPs on applied MSCs, and on the cells and tissues of the recipient. In this review we outline the current state of studies combining the administration of MSCs and the application of metal NPs, with a focus on perspectives to use such treatment for corneal and retinal injuries and diseases.

• Keywords
• combined application, mesenchymal stem cells, metal nanoparticles, ocular disorders, therapeutic effect,
• MeSH
• Combined Modality Therapy methods   MeSH
• Metal Nanoparticles * chemistry   therapeutic use   MeSH
• Humans MeSH
• Mesenchymal Stem Cells * cytology   MeSH
• Eye Diseases * therapy   MeSH
• Mesenchymal Stem Cell Transplantation * methods   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Review MeSH

Iron oxide nanoparticles (IONs) are frequently used in various biomedical applications, in particular as magnetic resonance imaging contrast agents in liver imaging. Indeed, number of IONs have been withdrawn due to their poor clinical performance. Yet comprehensive understanding of their interactions with hepatocytes remains relatively limited. Here we investigated how iron oxide nanocubes (IO-cubes) and clusters of nanocubes (IO-clusters) affect distinct human hepatic cell lines. The viability of HepG2, Huh7 and Alexander cells was concentration-dependently decreased after exposure to either IO-cubes or IO-clusters. We found similar cytotoxicity levels in three cell lines triggered by both nanoparticle formulations. Our data indicate that different expression levels of Bcl-2 predispose cell death signaling mediated by nanoparticles. Both nanoparticles induced rather apoptosis than autophagy in HepG2. Contrary, IO-cubes and IO-clusters trigger distinct cell death signaling events in Alexander and Huh7 cells. Our data clarifies the mechanism by which cubic nanoparticles induce autophagic flux and the mechanism of subsequent toxicity. These findings imply that the cytotoxicity of ION-based contrast agents should be carefully considered, particularly in patients with liver diseases.

• Keywords
• Apoptosis, Autophagy, Cytotoxicity, Iron oxide nanoparticles, Magnetic resonance imaging,
• Publication type
• Journal Article MeSH

Spinal cord injury (SCI) is a serious trauma, which often results in a permanent loss of motor and sensory functions, pain and spasticity. Despite extensive research, there is currently no available therapy that would restore the lost functions after SCI in human patients. Advanced treatments use regenerative medicine or its combination with various interdisciplinary approaches such as tissue engineering or biophysical methods. This review summarizes and critically discusses the research from specific interdisciplinary fields in SCI treatment such as the development of biomaterials as scaffolds for tissue repair, and using a magnetic field for targeted cell delivery. We compare the treatment effects of synthetic non-degradable methacrylate-based hydrogels and biodegradable biological scaffolds based on extracellular matrix. The systems using magnetic fields for magnetically guided delivery of stem cells loaded with magnetic nanoparticles into the lesion site are then suggested and discussed.

• Keywords
• Biomaterials, Cell delivery, Hydrogel, Magnetic field, Spinal cord injury,
• MeSH
• Biocompatible Materials pharmacology   therapeutic use   MeSH
• Hydrogels therapeutic use   MeSH
• Humans MeSH
• Magnetic Field Therapy methods   trends   MeSH
• Spinal Cord Injuries physiopathology   therapy   MeSH
• Nerve Regeneration drug effects   physiology   MeSH
• Stem Cell Transplantation methods   trends   MeSH
• Animals MeSH
• Check Tag
• Humans MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Review MeSH
• Names of Substances
• Biocompatible Materials MeSH
• Hydrogels MeSH

Lysosome-activated apoptosis represents an alternative method of overcoming tumor resistance compared to traditional forms of treatment. Pulsed magnetic fields open a new avenue for controlled and targeted initiation of lysosomal permeabilization in cancer cells via mechanical actuation of magnetic nanomaterials. In this study we used a noninvasive tool; namely, a benchtop pulsed magnetic system, which enabled remote activation of apoptosis in liver cancer cells. The magnetic system we designed represents a platform that can be used in a wide range of biomedical applications. We show that liver cancer cells can be loaded with superparamagnetic iron oxide nanoparticles (SPIONs). SPIONs retained in lysosomal compartments can be effectively actuated with a high intensity (up to 8 T), short pulse width (~15 µs), pulsed magnetic field (PMF), resulting in lysosomal membrane permeabilization (LMP) in cancer cells. We revealed that SPION-loaded lysosomes undergo LMP by assessing an increase in the cytosolic activity of the lysosomal cathepsin B. The extent of cell death induced by LMP correlated with the accumulation of reactive oxygen species in cells. LMP was achieved for estimated forces of 700 pN and higher. Furthermore, we validated our approach on a three-dimensional cellular culture model to be able to mimic in vivo conditions. Overall, our results show that PMF treatment of SPION-loaded lysosomes can be utilized as a noninvasive tool to remotely induce apoptosis.

• Keywords
• apoptosis, lysosomal death pathways, lysosomal membrane permeabilization, magnetic nanoparticles, pulsed magnetic field,
• Publication type
• Journal Article MeSH

Proteins of the mammalian target of rapamycin (mTOR) signaling axis are overexpressed or mutated in cancers. However, clinical inhibition of mTOR signaling as a therapeutic strategy in oncology shows rather limited progress. Nanoparticle-based mTOR targeted therapy proposes an attractive therapeutic option for various types of cancers. Along with the progress in the biomedical applications of nanoparticles, we start to realize the challenges and opportunities that lie ahead. Here, we critically analyze the current literature on the modulation of mTOR activity by nanoparticles, demonstrate the complexity of cellular responses to functionalized nanoparticles, and underline challenges lying in the identification of the molecular mechanisms of mTOR signaling affected by nanoparticles. We propose the idea that subcytotoxic doses of nanoparticles could be relevant for the induction of subcellular structural changes with possible involvement of mTORC1 signaling. The evaluation of the mechanisms and therapeutic effects of nanoparticle-based mTOR modulation will provide fundamental knowledge which could help in developing safe and efficient nano-therapeutics.

• Keywords
• lysosomes, mTOR, molecular targeting, nanoparticles, reactive oxygen species,
• Publication type
• Journal Article MeSH
• Review MeSH

Physics-based biomedical approaches have proved their importance for the advancement of medical sciences and especially in medical diagnostics and treatments. Thus, the expectations regarding development of novel promising physics-based technologies and tools are very high. This review describes the latest research advances in biomedical applications of external physical cues. We overview three distinct topics: using high-gradient magnetic fields in nanoparticle-mediated cell responses; non-thermal plasma as a novel bactericidal agent; highlights in understanding of cellular mechanisms of laser irradiation. Furthermore, we summarize the progress, challenges and opportunities in those directions. We also discuss some of the fundamental physical principles involved in the application of each cue. Considerable technological success has been achieved in those fields. However, for the successful clinical translation we have to understand the limitations of technologies. Importantly, we identify the misconceptions pervasive in the discussed fields.

• Keywords
• cell signaling, cytotoxicity, lasers, magnetic nanoparticles, non-thermal plasma,
• Publication type
• Journal Article MeSH
• Review MeSH

Specifically designed and functionalized nanoparticles hold great promise for biomedical applications. Yet, the applicability of nanoparticles is critically predetermined by their surface functionalization and biodegradability. Here we demonstrate that amino-functionalized polystyrene nanoparticles (PS-NH2), but not amino- or hydroxyl-functionalized silica particles, trigger cell death in hepatocellular carcinoma Huh7 cells. Importantly, biodegradability of nanoparticles plays a crucial role in regulation of essential cellular processes. Thus, biodegradable silica nanoparticles having the same shape, size and surface functionalization showed opposite cellular effects in comparison with similar polystyrene nanoparticles. At the molecular level, PS-NH2 obstruct and amino-functionalized silica nanoparticles (Si-NH2) activate the mTOR signalling in Huh7 and HepG2 cells. PS-NH2 induced time-dependent lysosomal destabilization associated with damage of the mitochondrial membrane. Solely in PS-NH2-treated cells, permeabilization of lysosomes preceded cell death. Contrary, Si-NH2 nanoparticles enhanced proliferation of HuH7 and HepG2 cells. Our findings demonstrate complex cellular responses to functionalized nanoparticles and suggest that nanoparticles can be used to control activation of mTOR signaling with subsequent influence on proliferation and viability of HuH7 cells. The data provide fundamental knowledge which could help in developing safe and efficient nano-therapeutics.

• MeSH
• Adsorption MeSH
• Amines chemistry   MeSH
• Carcinoma, Hepatocellular metabolism   pathology   MeSH
• Protein Conformation MeSH
• Lysosomes metabolism   MeSH
• Cell Line, Tumor MeSH
• Liver Neoplasms metabolism   pathology   MeSH
• Nanoparticles chemistry   MeSH
• Silicon Dioxide chemistry   MeSH
• Permeability MeSH
• Polystyrenes chemistry   MeSH
• Surface Properties MeSH
• Cell Proliferation MeSH
• Ribonucleases metabolism   MeSH
• Serum Albumin, Bovine metabolism   MeSH
• Signal Transduction * MeSH
• Cattle MeSH
• TOR Serine-Threonine Kinases metabolism   MeSH
• Animals MeSH
• Check Tag
• Cattle MeSH
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH
• Names of Substances
• Amines MeSH
• Silicon Dioxide MeSH
• Polystyrenes MeSH
• Ribonucleases MeSH
• Serum Albumin, Bovine MeSH
• TOR Serine-Threonine Kinases MeSH