Liposomes Composed by Membrane Lipid Extracts from Macrophage Cell Line as a Delivery of the Trypanocidal N,N'-Squaramide 17 towards Trypanosoma cruzi

Oxocarbon Acids and their Derivatives in Biological and Medicinal Chemistry

The biological and medicinal chemistry of the oxocarbon acids 2,3- dihydroxycycloprop-2-en-1-one (deltic acid), 3,4-dihydroxycyclobut-3-ene-1,2-dione (squaric acid), 4,5-dihydroxy-4-cyclopentene-1,2,3-trione (croconic acid), 5,6-dihydroxycyclohex- 5-ene-1,2,3,4-tetrone (rhodizonic acid) and their derivatives is reviewed and their key chemical properties and reactions are discussed. Applications of these compounds as potential bioisosteres in biological and medicinal chemistry are examined. Reviewed areas include cell imaging, bioconjugation reactions, antiviral, antibacterial, anticancer, enzyme inhibition, and receptor pharmacology.

Rapid and Versatile Biosensing of Liposome Encapsulation Efficiency Using Electrical Conductivity Sensor

Liposomes are prominent nanosystems for drug delivery, with potential extending beyond isolated drugs. Ethanol-aqueous plant extracts can be encapsulated within liposomes to protect bioactive compounds (secondary metabolites) from rapid oxidation and enable sustained release. Determining which compound classes are present in each extract and the encapsulation efficiency (EE) of these extracts in liposomes is crucial for nanocarrier functionality. This involves assessing the ratio of bioactive substances within liposomes to the total content. However, quantifying EE for non-isolated compounds poses challenges due to the need for advanced analytical equipment and biosensing approaches. This study introduces an innovative method for EE quantification, using a conductivity electrode (k = 0.842/cm) to establish an EE biosensing technology. By correlating dynamic light scattering (DLS), zeta potential (ZP), and electrical conductivity (Cnd) data with the conductivity meter's calibration curve, a robust relationship between the free extract concentration and Cnd (r2 ≥ 0.950) was established. Lavender-loaded liposomes demonstrated an EE of 56.33%, while wormwood and oregano formulations exhibited high EEs of 94.33% and 91.70%, respectively. In contrast, sage-loaded liposomes exhibited an inadequate EE, encapsulating only approximately 0.57% of the extract. The straightforward quantification of the free extract within liposome formulations, compared to more complex approaches, could facilitate EE determination and support future characterizations.

From Benznidazole to New Drugs: Nanotechnology Contribution in Chagas Disease

Chagas disease is a neglected tropical disease caused by the protozoan Trypanosoma cruzi. Benznidazole and nifurtimox are the two approved drugs for their treatment, but both drugs present side effects and efficacy problems, especially in the chronic phase of this disease. Therefore, new molecules have been tested with promising results aiming for strategic targeting action against T. cruzi. Several studies involve in vitro screening, but a considerable number of in vivo studies describe drug bioavailability increment, drug stability, toxicity assessment, and mainly the efficacy of new drugs and formulations. In this context, new drug delivery systems, such as nanotechnology systems, have been developed for these purposes. Some nanocarriers are able to interact with the immune system of the vertebrate host, modulating the immune response to the elimination of pathogenic microorganisms. In this overview of nanotechnology-based delivery strategies for established and new antichagasic agents, different strategies, and limitations of a wide class of nanocarriers are explored, as new perspectives in the treatment and monitoring of Chagas disease.

Toward the next-generation phyto-nanomedicines: cell-derived nanovesicles (CDNs) for natural product delivery

Phytochemicals are plant-derived bioactive compounds, which have been widely used for therapeutic purposes. Due to the poor water-solubility, low bioavailability and non-specific targeting characteristic, diverse classes of nanocarriers are utilized for encapsulation and delivery of bio-effective agents. Cell-derived nanovesicles (CDNs), known for exosomes or extracellular vesicles (EVs), are biological nanoparticles with multiple functions. Compared to the artificial counterpart, CDNs hold great potential in drug delivery given the higher stability, superior biocompatibility and the lager capability of encapsulating bioactive molecules. Here, we provide a bench-to-bedside review of CDNs-based nanoplatform, including the bio-origin, preparation, characterization and functionalization. Beyond that, the focus is laid on the therapeutic effect of CDNs-mediated drug delivery for natural products. The state-of-art development as well as some pre-clinical applications of using CDNs for disease treatment is also summarized. It is highly expected that the continuing development of CDNs-based delivery systems will further promote the clinical utilization and translation of phyto-nanomedicines.

Thermoresponsive chimeric nanocarriers as drug delivery systems

Chimeric or mixed nanosystems belong to the class of advanced therapeutics. Their distinctive characteristic compared with other types of nanoparticles is that they combine two or more different classes of biomaterials. These platforms have created a promising and versatile field of nanomedicine, incorporating materials that are biocompatible, such as lipids, but also functional, such as stimuli-responsive polymers. In the present work, thermoresponsive chimeric nanocarriers composed of l-α-phosphatidylcholine (Egg, Chicken) (EPC) phospholipids and poly(N-isopropylacrylamide)-b-poly(lauryl acrylate) (PNIPAM-b-PLA) block copolymers were designed and developed. Initially, model lipid bilayers with incorporated polymers and drug molecule TRAM-34 were built and studied for their thermodynamics, in order to assess the stability and functionality of the systems. Chimeric nanoparticles of EPC and PNIPAM-b-PLA were then developed and evaluated for their physicochemical properties in different medium conditions, as well as for their morphology. Polymer incorporation led to alterations in the properties and morphology of the nanoparticles, while interactions with serum proteins were absent. TRAM-34 was also incorporated inside the developed nanocarriers, followed by incorporation and release studies, which revealed the functionality of the system in elevated temperature conditions. Finally, in vitro studies on normal cells suggest the biocompatibility of these nanosystems. The proposed platforms are promising for further studies and applications in vitro and in vivo.

Nano Based Approach for the Treatment of Neglected Tropical Diseases

Neglected tropical diseases (NTDs) afflict more than one billion peoples in the world’s poorest countries. The World Health Organization (WHO) has recorded seventeen NTDs in its portfolio, mainly caused by bacterial, protozoal, parasitic, and viral infections. Each of the NTDs has its unique challenges on human health such as interventions for control, prevention, diagnosis, and treatment. Research for the development of new drug molecules against NTDs has not been undertaken by pharmaceutical industries due to high investment and low-returns, which results in limited chemotherapeutics in the market. In addition, conventional chemotherapies for the treatment of NTDs are unsatisfactory due to its low efficacy, increased drug resistance, short half-life, potential or harmful fatal toxic side effects, and drug incompetence to reach the site of parasite infection. In this context, active chemotherapies are considered to be re-formulated by overcoming these toxic side effects via a tissue-specific targeted drug delivery system. This review mainly emphasizes the recent developments of nanomaterial-based drug delivery systems for the effective treatment of NTDs especially sleeping sickness, leishmaniasis, chagas disease, soil-transmitted helminthiasis, african trypanosomiasis and dengue. Nanomaterials based drug delivery systems offer enhanced and effective alternative therapy through the re-formulation approach of conventional drugs into site-specific targeted delivery of drugs.