Innovative Materials with Possible Applications in the Wound Dressings Field: Alginate-Based Films with Moringa oleifera Extract.

For a long time, biopolymers have proven their effectiveness in the development of materials with various applications, lately those intended for the biomedical and pharmaceutical industries, due to their high biocompatibility and non-toxic, non-allergenic, and non-immunogenic nature. The ability to incorporate various active substances in this matrix has yielded materials with characteristics that are far superior to those of classic, conventional ones. The beneficial effects of consuming Moringa oleifera have promoted the use of this plant, from Ayurvedic to classical medicine. The addition of such compounds in the materials intended for the treatment of surface wounds may represent the future of the development of innovative dressings. This study followed the development of materials based on sodium alginate and moringa powder or essential oil for use as dressings, pads, or sheets. Thus, three materials with the addition of 10-30% moringa powder and three materials with the addition of 10-30% essential oil were obtained. The data were compared with those of the control sample, with sodium alginate and plasticizer. The microtopography indicated that the materials have a homogeneous matrix that allows them to incorporate and maintain natural compounds with prolonged release. For example, the sample with 30% moringa essential oil kept its initial shape and did not disintegrate, although the swelling ratio value reached 4800% after 20 min. After testing the mechanical properties, the same sample had the best tensile strength (TS = 0.248 MPa) and elongation (31.41%), which is important for the flexibility of the dressing. The same sample exhibited a very high antioxidant capacity (60.78% inhibition). The materials obtained with moringa powder added presented good values of physical and mechanical properties, which supports their use as wound dressings for short-term application and the release of embedded compounds. According to the obtained results, all the biopolymeric materials with moringa added can be used as dressings for different wound types.

Long COVID: Molecular Mechanisms and Detection Techniques.

Long COVID, also known as post-acute sequelae of SARS-CoV-2 infection (PASC), has emerged as a significant health concern following the COVID-19 pandemic. Molecular mechanisms underlying the occurrence and progression of long COVID include viral persistence, immune dysregulation, endothelial dysfunction, and neurological involvement, and highlight the need for further research to develop targeted therapies for this condition. While a clearer picture of the clinical symptomatology is shaping, many molecular mechanisms are yet to be unraveled, given their complexity and high level of interaction with other metabolic pathways. This review summarizes some of the most important symptoms and associated molecular mechanisms that occur in long COVID, as well as the most relevant molecular techniques that can be used in understanding the viral pathogen, its affinity towards the host, and the possible outcomes of host-pathogen interaction.

Cu and Zn Interactions with Peptides Revealed by High-Resolution Mass Spectrometry.

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by abnormal extracellular amyloid-beta (Aß) peptide depositions in the brain. Among amorphous aggregates, altered metal homeostasis is considered a common risk factor for neurodegeneration known to accelerate plaque formation. Recently, peptide-based drugs capable of inhibiting amyloid aggregation have achieved unprecedented scientific and pharmaceutical interest. In response to metal ions binding to Aß peptide, metal chelation was also proposed as a therapy in AD. The present study analyzes the interactions formed between NAP octapeptide, derived from activity-dependent neuroprotective protein (ADNP), amyloid Aß(9-16) fragment and divalent metal ions such as Cu and Zn. The binding affinity studies for Cu and Zn ions of synthetic NAP peptide and Aß(9-16) fragment were investigated by matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS), electrospray ion trap mass spectrometry (ESI-MS) and atomic force microscopy (AFM). Both mass spectrometric methods confirmed the formation of metal-peptide complexes while the AFM technique provided morphological and topographic information regarding the influence of metal ions upon peptide crystallization. Our findings showed that due to a rich histidine center, the Aß(9-16) fragment is capable of binding metal ions, thus becoming stiff and promoting aggregation of the entire amyloid peptide. Apart from this, the protective effect of the NAP peptide was found to rely on the ability of this octapeptide to generate both chelating properties with metals and interactions with Aß peptide, thus stopping its folding process.

The Use of Bioactive Compounds in Hyperglycemia- and Amyloid Fibrils-Induced Toxicity in Type 2 Diabetes and Alzheimer's Disease.

It has become increasingly apparent that defective insulin signaling may increase the risk for developing Alzheimer's disease (AD), influence neurodegeneration through promotion of amyloid formation or by increasing inflammatory responses to intraneuronal ß-amyloid. Recent work has demonstrated that hyperglycemia is linked to cognitive decline, with elevated levels of glucose causing oxidative stress in vulnerable tissues such as the brain. The ability of ß-amyloid peptide to form ß-sheet-rich aggregates and induce apoptosis has made amyloid fibrils a leading target for the development of novel pharmacotherapies used in managing and treatment of neuropathological conditions such as AD-related cognitive decline. Additionally, deposits of ß-sheets folded amylin, a glucose homeostasis regulator, are also present in diabetic patients. Thus, therapeutic compounds capable of reducing intracellular protein aggregation in models of neurodegenerative disorders may prove useful in ameliorating type 2 diabetes mellitus symptoms. Furthermore, both diabetes and neurodegenerative conditions, such as AD, are characterized by chronic inflammatory responses accompanied by the presence of dysregulated inflammatory biomarkers. This review presents current evidence describing the role of various small bioactive molecules known to ameliorate amyloidosis and subsequent effects in prevention and development of diabetes and AD. It also highlights the potential efficacy of peptide-drug conjugates capable of targeting intracellular targets.