Halloysite Nanotubes and Sepiolite for Health Applications.

The need for safe, therapeutically effective, and patient-compliant drug delivery systems continuously leads researchers to design novel tools and strategies. Clay minerals are widely used in drug products both as excipients and active agents but, in recent years, there has been a growing interest in research aimed at the development of new organic or inorganic nanocomposites. The attention of the scientific community has been drawn by nanoclays, thanks to their natural origin, worldwide abundance, availability, sustainability, and biocompatibility. In this review, we focused our attention on the studies inherent to the pharmaceutical and biomedical applications of halloysite and sepiolite, and their semi-synthetic or synthetic derivatives, as drug delivery systems. After having described the structure of both materials and their biocompatibility, we delineate the use of the nanoclays to enhance the stability, the controlled release, the bioavailability, and the adsorption properties of drugs. Several types of surface functionalization have been discussed, showing that these materials could be used for the development of an innovative therapeutic approach.

Nanomaterials: A Review about Halloysite Nanotubes, Properties, and Application in the Biological Field.

The use of synthetic materials and the attention towards environmental hazards and toxicity impose the development of green composites with natural origins. Clay is one of the candidates for this approach. Halloysite is a natural clay mineral, a member of the Kaolin group, with characteristic tubular morphology, usually named halloysite nanotubes (HNTs). The different surface chemistry of halloysite allows the selective modification of both the external surface and the inner lumen by supramolecular or covalent interactions. An interesting aspect of HNTs is related to the possibility of introducing different species that can be released more slowly compared to the pristine compound. Due to their unique hollow morphology and large cavity, HNTs can be employed as an optimal natural nanocarrier. This review discusses the structure, properties, and application of HNTs in the biological field, highlighting their high biocompatibility, and analyse the opportunity to use new HNT hybrids as drug carriers and delivery systems.

An Albanian open source telemedicine platform.

INTRODUCTION: The use of open source technologies to create collaboration platforms can produce huge advantages with small investment. MATERIALS AND METHODS: We set up a telemedicine network for a healthcare district with typical centralization issues of developing countries. Our network was built using broadband Internet connection, and the digital divide in rural areas was reduced by means of wireless Internet connection. A software infrastructure was deployed on the network to implement the collaboration platform among different healthcare facilities. RESULTS: We obtained an integrated platform with modest investment in hardware and operating systems and no costs for application software. Messaging, content management, information sharing, and videoconferencing are among the available services of the infrastructure. Furthermore, open source software is managed and continuously updated by active communities, making it possible to obtain systems similar to commercial ones in terms of quality and reliability. CONCLUSIONS: As the use of free software in public administration is being widely promoted across the European Union, our experience may provide an example to implement similar infrastructures in the field of healthcare and welfare.

Study of Uptake Mechanisms of Halloysite Nanotubes in Different Cell Lines.

PURPOSE: Halloysite nanotubes (HNTs) are a natural aluminosilicate clay with a chemical formula of Al2Si2O5(OH)4×nH2O and a hollow tubular structure. Due to their peculiar structure, HNTs can play an important role as a drug carrier system. Currently, the mechanism by which HNTs are internalized into living cells, and what is the transport pathway, is still unclear. Therefore, this study aimed at establishing the in vitro mechanism by which halloysite nanotubes could be internalized, using phagocytic and non-phagocytic cell lines as models. METHODS: The HNT/CURBO hybrid system, where a fluorescent probe (CURBO) is confined in the HNT lumen, has been used as a model to study the transport pathway mechanisms of HNTs. The cytocompatibility of HNT/CURBO on cell lines model was investigated by MTS assay. In order to identify the internalization pathway involved in the cellular uptake, we performed various endocytosis-inhibiting studies, and we used fluorescence microscopy to verify the nanomaterial internalization by cells. We evaluated the haemolytic effect of HNT/CURBO placed in contact with human red blood cells (HRBCs), by reading the absorbance value of the supernatant at 570 nm. RESULTS: The HNT/CURBO is highly biocompatible and does not have an appreciable haemolytic effect. The results of the inhibition tests have shown that the internalization process of nanotubes occurs in an energy-dependent manner in both the investigated cell lines, although they have different characteristics. In particular, in non-phagocytic cells, clathrin-dependent and independent endocytosis are involved. In phagocytic cells, in addition to phagocytosis and clathrin-dependent endocytosis, microtubules also participate in the halloysite cellular trafficking. Upon internalization by cells, HNT/CURBO is localized in the cytoplasmic area, particularly in the perinuclear region. CONCLUSION: Understanding the cellular transport pathways of HNTs can help in the rational design of novel drug delivery systems and can be of great value for their applications in biotechnology.

A new p65 isoform that bind the glucocorticoid hormone and is expressed in inflammation liver diseases and COVID-19.

Inflammation is a physiological process whose deregulation causes some diseases including cancer. Nuclear Factor kB (NF-kB) is a family of ubiquitous and inducible transcription factors, in which the p65/p50 heterodimer is the most abundant complex, that play critical roles mainly in inflammation. Glucocorticoid Receptor (GR) is a ligand-activated transcription factor and acts as an anti-inflammatory agent and immunosuppressant. Thus, NF-kB and GR are physiological antagonists in the inflammation process. Here we show that in mice and humans there is a spliced variant of p65, named p65 iso5, which binds the corticosteroid hormone dexamethasone amplifying the effect of the glucocorticoid receptor and is expressed in the liver of patients with hepatic cirrhosis and hepatocellular carcinoma (HCC). Furthermore, we have quantified the gene expression level of p65 and p65 iso5 in the PBMC of patients affected by SARS-CoV-2 disease. The results showed that in these patients the p65 and p65 iso5 mRNA levels are higher than in healthy subjects. The ability of p65 iso5 to bind dexamethasone and the regulation of the glucocorticoid (GC) response in the opposite way of the wild type improves our knowledge and understanding of the anti-inflammatory response and identifies it as a new therapeutic target to control inflammation and related diseases.

Multifunctional Carrier Based on Halloysite/Laponite Hybrid Hydrogel for Kartogenin Delivery.

A novel carrier system based on halloysite nanotubes (HNT), for the potential intraarticular delivery of kartogenin (KGN) by means laponite (Lap) hydrogel (HNT/KGN/Lap), is developed. The drug was first loaded into HNT, and the hybrid composite obtained was used as filler for laponite hydrogel. Both the filler and the hydrogel were thoroughly investigated by several techniques and the hydrogel morphology was imaged by transmission electron microscopy. Furthermore, the gelating ability of laponite in the presence of the filler and the rheological properties of the hybrid hydrogel were also investigated. The kinetic release of kartogenin from HNT and HNT/Lap hybrid hydrogel was studied both in physiological conditions and in ex vivo synovial fluid. In the last case, the kinetic results highlighted that HNT carrier can effectively release KGN in a sustained manner for at least 38 days. Finally, a preliminary biological assays showed that the HNT/KGN/Lap hybrid hydrogel did not exhibit any cytotoxic effect.

Halloysite nanotubes-carbon dots hybrids multifunctional nanocarrier with positive cell target ability as a potential non-viral vector for oral gene therapy.

HYPOTHESIS: The use of non-viral vectors for gene therapy is hindered by their lower transfection efficiency and their lacking of self-track ability. EXPERIMENTS: This study aims to investigate the biological properties of halloysite nanotubes-carbon dots hybrid and its potential use as non-viral vector for oral gene therapy. The morphology and the chemical composition of the halloysite hybrid were investigated by means of high angle annular dark field scanning TEM and electron energy loss spectroscopy techniques, respectively. The cytotoxicity and the antioxidant activity were investigated by standard methods (MTS, DPPH and H2O2, respectively) using human cervical cancer HeLa cells as model. Studies of cellular uptake were carried out by fluorescence microscopy. Finally, we investigated the loading and release ability of the hybrid versus calf thymus DNA by fluorescence microscopy, circular dichroism, dynamic light scattering and ζ-potential measurements. FINDINGS: All investigations performed confirmed the existence of strong electrostatic interactions between the DNA and the halloysite hybrid, so it shows promise as a multi-functional cationic non-viral vector that has also possesses intracellular tracking capability and promising in vitro antioxidant potential.

BRAFV600E mutation, TIMP-1 upregulation, and NF-κB activation: closing the loop on the papillary thyroid cancer trilogy.

BRAF(V600E) is the most common mutation found in papillary thyroid carcinoma (PTC). Tissue inhibitor of metalloproteinases (TIMP-1) and nuclear factor (NF)-κB have been shown to play an important role in thyroid cancer. In particular, TIMP-1 binds its receptor CD63 on cell surface membrane and activates Akt signaling pathway, which is eventually responsible for its anti-apoptotic activity. The aim of our study was to evaluate whether interplay among these three factors exists and exerts a functional role in PTCs. To this purpose, 56 PTC specimens were analyzed for BRAF(V600E) mutation, TIMP-1 expression, and NF-κB activation. We found that BRAF(V600E) mutation occurs selectively in PTC nodules and is associated with hyperactivation of NF-κB and upregulation of both TIMP-1 and its receptor CD63. To assess the functional relationship among these factors, we first silenced BRAF gene in BCPAP cells, harboring BRAF(V600E) mutation. We found that silencing causes a marked decrease in TIMP-1 expression and NF-κB binding activity, as well as decreased invasiveness. After treatment with specific inhibitors of MAPK pathway, we found that only sorafenib was able to increase IκB-α and reduce both TIMP-1 expression and Akt phosphorylation in BCPAP cells, indicating that BRAF(V600E) activates NF-κB and this pathway is MEK-independent. Taken together, our findings demonstrate that BRAF(V600E) causes upregulation of TIMP-1 via NF-κB. TIMP-1 binds then its surface receptor CD63, leading eventually to Akt activation, which in turn confers antiapoptotic behavior and promotion of cell invasion. The recognition of this functional trilogy provides insight on how BRAF(V600E) determines cancer initiation, progression, and invasiveness in PTC, also identifying new therapeutic targets for the treatment of highly aggressive forms.