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The use of nanoparticles as drug delivery systems to simultaneously carry several therapeutic agents is an attractive idea to create new synergic treatments and to develop the next generation of cancer therapies. Therefore, the goal of this study was the simultaneous encapsulation of a hydrophilic drug, sodium diethyldithiocarbamate (DETC), and a hydrophobic drug, 4-nitrochalcone (4NC), in beeswax nanoparticles (BNs) to evaluate the in vitro synergic activity of this combination against melanoma (B16F10) cells. BNs were prepared by water/oil/water double emulsion in the absence of organic solvents. Transmission electron microscopy imaging and dynamic light scattering analyses indicated the formation of BNs with a semispherical shape, average diameter below 250 nm, relatively narrow distributions, and negative zeta potential. The double emulsion technique proved to be effective for the simultaneous encapsulation of DETC and 4NC with efficiencies of 86.2% and 98.7%, respectively, and this encapsulation did not affect the physicochemical properties of the BNs. DETC and 4NC loaded in BNs exhibited a higher cytotoxicity toward B16F10 cells than free 4NC and DETC. This simultaneous encapsulation led to a synergic effect of DETC and 4NC on B16F10 cells, decreasing the cell viability from 46% (DETC BNs) and 54% (4NC BNs) to 64% (DETC+4NC BNs). Therefore, the IC 50 of DETC+4NC was also lower than that of either when individually encapsulated, and that of free DETC or 4NC. Therefore, DETC and 4NC were efficiently simultaneously encapsulated in BNs and this drug combination was able to generate an in vitro synergic therapeutic effect on B16F10 cells. • Colloidally stable beeswax nanoparticles by the double emulsion/melt dispersion method • Simultaneous encapsulation of hydrophobic and hydrophilic drugs for melanoma treatment • DETC and 4NC exerted synergic inhibitory effect over in vitro melanoma cells [ABSTRACT FROM AUTHOR]

• The reverse phase-evaporation method resulted in the successful encapsulation of drug. • The liposome provided greater protection to the drugs when exposed to non-tumor cells. • Phototoxicity assays were performed in human breast (MDA-MB 231) cells. • Simultaneous treatment was generated by inhibition of antioxidant enzymes SOD/GSH. There has been considerable interest in the development of novel photosensitisers for photodynamic therapy (PDT). The use of liposomes as drug delivery systems containing simultaneously two or more drugs is an attractive idea to create a new platform for PDT application. Therefore, the aim of this study was to evaluate the synergistic effect of diethyldithiocarbamate (DETC) and zinc phthalocyanine (PDT) co-encapsulated in liposomes. The reverse-phase evaporation method resulted in the successful encapsulation of DETC and ZnPc in liposomes, with encapsulation efficiencies above 85 %, mean size of 308 nm, and zeta potential of ― 36 mV. The co-encapsulation decreased the cytotoxic effects in mouse embryo fibroblast (NIH3T3) cells and inhibited damage to human erythrocytes compared to free DETC + ZnPc. In addition, both the free drugs and co-encapsulated ones promoted more pronounced phototoxic effects on human breast cancer cells (MDA-MB231) compared to treatment with ZnPc alone. This synergistic effect was determined by DETC-induced decreases in the antioxidant enzyme activity of superoxide dismutase (SOD) and glutathione (GSH). [ABSTRACT FROM AUTHOR]

The combination of hyperthermia and chemotherapy has a potential synergic effect in antitumor activity. The development of new biocompatible and biodegradable polymers to simultaneously encapsulate magnetic nanoparticles (MNPs) and antitumoral drugs offer new cancer treatment opportunities. Here, biodegradable and biocompatible poly(thioether-ester) (PTEe) was used to encapsulate MNPs and 4-nitrochalcone (4NC) using miniemulsification and solvent evaporation. The resulting hybrid particles (MNPs-4NC-PTEe) had nanometer-scale diameters, spherical morphology, negative surface charge, high encapsulation efficiency, and superparamagnetic properties. Results showed that 4NC release occurred through diffusion. Free 4NC and MNPs + 4NC-PTEe did not have any cytotoxic effect on erythrocytes and mouse embryonic fibroblast (NIH3T3) cells. 4NC antitumor activity was verified on human cervical cancer (HeLa) and melanoma (B16F10) cells. Cellular uptake of MNPs + 4NC-PTEe nanoparticles was higher in HeLa cells compared to B16F10 and NIH3T3 cells. The hyperthermia application (115 kHz–500 Oe) potentiated the 4NC effects on HeLa and B16F10 cells when MNPs + 4NC-PTEe nanoparticles were used, indicating more effective antitumor activity. We concluded that the use of MNPs + 4NC-PTEe nanoparticles associated with hyperthermia is a promising form of treatment for some types of cancers. [ABSTRACT FROM AUTHOR]

Emerging pollutants are compounds arising from human development, such as personal care products and pharmaceutical drugs, that reach rivers, lakes, and groundwater through wastewaters and have a potential risk to human health and the environment, which are not yet addressed in any laws. Anticancer drugs are a class of pharmaceutical drugs that exhibit recalcitrant behavior to conventional wastewater treatments. They have been found in domestic, industrial, and hospital wastewater, and some studies proved they can be mutagenic, genotoxic, and teratogenic to humans and wildlife. On this subject, the present study describes the enzymatic degradation of etoposide by several laccase activities and pHs. Moreover, the kinetic studies were performed in etoposide concentrations ranging from 500 to 18,000 µg·L−1. The degradation products were investigated by high-performance liquid chromatography/mass spectrometry (LC–MS/MS), and the toxicity was evaluated against L-929 cell line. The results showed that the laccase activity of 1100 U·L−1 completely degraded etoposide in 60 min, and even the laccase activity of 55 U·L−1 could remove 86% of the etoposide after 360 min. Laccase also degraded etoposide in all evaluated pHs, even in conditions similar to wastewater treatment plants (pH 6 and 7). The biocatalysis followed a first-order kinetics behavior and the degradation kinetics constant was k = 0.0477 min−1. The mass spectroscopy suggested that the degradation mechanism of etoposide was by dehydration and demethylation. Furthermore, laccase degraded etoposide to a non-toxic bio-product in which all tested concentrations show no reduction in metabolic activity of the tested cell line. The results of the etoposide degradation strongly suggested that laccase shows the potential to remove anticancer drugs in wastewater treatment plants. [ABSTRACT FROM AUTHOR]

The use of compounds from natural or synthetic sources and nanotechnology may represent an alternative to develop new drugs for the leishmaniasis treatment. DETC is an inhibitor of the SOD1 enzyme, which leads to increased ROS production, important for the elimination of Leishmania. Thus, our objective was to assess the leishmanicidal in vitro effect of free Diethydithiocarbamate (DETC) and DETC loaded in beeswax-copaiba oil nanoparticles (DETC-Beeswax-CO Nps) on L. amazonensis forms and elucidate the possible mechanisms involved in the parasite death. DETC-Beeswax-CO Nps presented size below 200 nm, spherical morphology, negative zeta potential, and high encapsulation efficiency. Free DETC reduced the viability of promastigotes and increase ROS production, lower the mitochondrial membrane potential, cause phosphatidylserine exposure, and enhance plasma membrane permeability, in addition to promoting morphological changes in the parasite. Free DETC proved toxic in the assessment of toxicity to murine macrophages, however, the encapsulation of this compound was able to reduce these toxic effects on macrophages. DETC-Beeswax-CO Nps exerted anti-amastigote effect by enhancing the production of ROS, superoxide anion, TNF-α, IL-6, and reduced IL-10 in macrophages. Therefore, free DETC induces antipromastigote effect by apoptosis-like; and DETC-Beeswax-CO Nps exerted anti-leishmanial effect due to pro-oxidant and pro-inflammatory response. [ABSTRACT FROM AUTHOR]

Leishmaniasis is a neglected tropical disease that has a wide spectrum of clinical manifestations, ranging from visceral to cutaneous, with millions of new cases and thousands of deaths notified every year. The severity of the disease and its various clinical forms are determined by the species of the causative agent, Leishmania , as well as the host's immune response. Major challenges still exist in the diagnosis and treatment of leishmaniasis, and there is no vaccine available to prevent this disease in humans. Nanotechnology has emerged as a promising tool in a variety of fields. In this review, we highlight the main and most recent advances in nanomedicine to improve the diagnosis and treatment, as well as for the development of vaccines, for leishmaniasis. Nanomaterials are nanometric in size and can be produced by a variety of materials, including lipids, polymers, ceramics, and metals, with varying structures and morphologies. Nanotechnology can be used as biosensors to detect antibodies or antigens, thus improving the sensitivity and specificity of such immunological and molecular diagnostic tests. While in treatment, nanomaterials can act as drug carriers or, be used directly, to reduce any toxic effects of drug compounds to the host and to be more selective towards the parasite. Furthermore, preclinical studies show that different nanomaterials can carry different Leishmania antigens, or even act as adjuvants to improve a Th1 immune response in an attempt to produce an effective vaccine. [Display omitted] • Nanomaterials of various types can play an important role against leishmaniasis. • Nanomaterials can improve leishmaniasis diagnosis by increasing sensitivity/specificity. • Nanomaterials can reduce host toxicity and increase selectivity against the parasite. • Nanomaterials can be used as adjuvants and carriers of antigens. • Nanomaterials may stimulate a Th1 response, providing protection against Leishmania infection. [ABSTRACT FROM AUTHOR]

The Leishmaniasis treatment currently available involves some difficulties, such as high toxicity, variable efficacy, high cost, therefore, it is crucial to search for new therapeutic alternatives. Over the past few years, research on new drugs has focused on the use of natural compounds such as chalcones and nanotechnology. In this context, this research aimed at assessing the in vitro leishmanicidal activity of free 4-nitrochalcone (4NC) on promastigotes and encapsulated 4NC on L. amazonensis -infected macrophages, as well as their action mechanisms. Free 4NC was able to reduce the viability of promastigotes, induce reactive oxygen species production, decrease mitochondrial membrane potential, increase plasma membrane permeability, and expose phosphatidylserine, in addition to altering the morphology and lowering parasite cellular volume. Treatment containing encapsulated 4NC in beeswax-copaiba oil nanoparticles (4NC-beeswax-CO Nps) did not alter the viability of macrophages. Furthermore, 4NC-beeswax-CO Nps reduced the percentage of infected macrophages and the number of amastigotes per macrophages, increasing the production of reactive oxygen species, NO, TNF-α, and IL-10. Therefore, free 4NC proved to exert anti-promastigote effect, while 4NC-beeswax-CO Nps showed a leishmanicidal effect on L. amazonensis -infected macrophages by activating the macrophage microbicidal machinery. Image 1 [ABSTRACT FROM AUTHOR]