Anti-inflammatory, healing and antiophidic potential of Jatropha mollissima (Pohl) Baill. (Euphorbiaceae): From popular use to pharmaceutical formulation in gel.

Jatropha mollissima (Pohl) Baill. (Euphorbiaceae) is widely used in traditional medicine to treat inflammatory disorders. So, a topical gel containing the hydroethanolic extract of its leaves was developed and evaluated for its anti-inflammatory, wound healing, and antiophidic properties in mice. First, the chemical profile of different parts of the plant was characterized by liquid chromatography coupled to mass spectrometry (LC-MS) using molecular networking. In the leaf extract, 11 compounds were characterized, with a particular emphasis on the identification of flavonoids. The gel efficiently inhibited carrageenan-induced paw edema, as well as acute and chronic croton oil-induced ear edema models, thereby reducing inflammatory and oxidative parameters in inflamed tissues. Besides anti-inflammatory activity, the herbal gel showed significant wound healing activity. The edematogenic, hemorrhagic and dermonecrotic activities induced by Bothrops jararaca snake venom were effectively inhibited by the treatment with J. mollissima gel. The association with the herbal gel improved in up to 90% the efficacy of commercial snake antivenom in reduce venom-induced edema. Additionally, while antivenom was not able to inhibit venom-induced dermonecrosis, treatment with herbal gel reduced in 55% the dermonocrotic halo produced. These results demonstrate the pharmacological potential of the herbal gel containing J. mollissima extract, which could be a strong candidate for the development of herbal products that can be used to complement the current antivenom therapy against snake venom local toxicity.

Immobilization of Papain in Chitosan Membranes as a Potential Alternative for Skin Wounds.

Papain (an enzyme from the latex of Carica papaya) is an interesting natural bioactive macromolecule used as therapeutic alternative for wound healing due to debridement action in devitalized or necrotic tissues. However, its use in high doses can induce potential skin irritation and side effects. In this study, experiments explored the ability of chitosan membrane to immobilize papain, consequently improving enzymatic activity and controlling enzyme release. Papain-loading capacity was tested via experiments of force microscopy (AFM), scanning electron microscopy (SEM-FEG), and X-ray diffraction analyses. Fourier transform infrared spectroscopy and thermal analyses assessed the enzyme interactions with the copolymer. The investigation of the feasibility of membranes included pH on the surface, elasticity, and breaking strength measurements. The surface wettability and swelling capacity of different formulations revealed the best formulation for in vitro papain release experiments. The membranes had a transparent, rough, crystalline characteristic, which was homogeneous with the membrane within the neutrality. The immobilization of papain in the chitosan membrane resulted in a decrease in the vibration band characteristic of pure papain, suggesting a displacement in the vibration bands in the FTIR spectrum. The presence of papain decreased hydrophobicity on the surface of the membrane and disturbed the membrane's ability to swell. Chitosan membranes containing papain 2.5% (0.04 g) and 5.0% (0.08 g) preserved feasible properties and improved the enzymatic activity compared (0.87 ± 0.12 AU/mg and 1.59 ± 0.10 AU/mg) with a free papain sample (0.0042 ± 0.001 AU/mg). Concentrations of over 10% (0.16 g) led to phase separation into membranes. Chitosan membranes exhibited a slow papain release behavior adjusted via the Higushi model. The experimental achievements suggest a novel and promising method for the enhancement of papain. The results indicate the potential for prolonged bioactivity for use on wounds.

Modulation of hNav by Tst1, a ß-toxin purified from the scorpion Tityus stigmurus.

Scorpion venoms are known as a rich mixture of components, including peptides that can interact with different ion channels, particularly voltage-gated potassium channels (Kv), calcium channels (Cav) and sodium channels (Nav), essential membrane proteins for various physiological functions in organisms. The present work aimed to characterize the modulation of hNa+-channels by Tst1, a peptide purified from the venom of Tityus stigmurus, using whole-cell patch clamp. Tst1 at 100 nM provoked current inhibition in Nav 1.3 (85.23%), Nav 1.2 (67.26%) and Nav 1.4 (63.43%), while Nav 1.1, 1.5, 1.6, and 1.7 were not significantly affected. Tst1 also shifted the voltage of activation and steady-state inactivation to more hyperpolarized states and altered the recovery from inactivation of the channels, reducing repetitive firing of cells, which was more effective in Nav 1.3. Tst1 also demonstrated that the effect on Nav 1.3 is dose-dependent, with an IC50 of 8.79 nM. Taken together, these results confirmed that Tst1, the first Tityus stigmurus NaScTx assayed in relation to Nav channels, is a ß-toxin, as was previously suggested due to its amino acid sequence. KEY CONTRIBUTION: First ß-toxin purified from the venom of Tityus stigmurus scorpion broadly characterized in hNa+-channels.

Antibacterial and antibiofilm activities of thiazolidine-2,4-dione and 4-thioxo-thiazolidin-2-one derivatives against multidrug-resistant Staphylococcus aureus clinical isolates.

AIMS: Antimicrobial resistance is one of the highest priorities in global public health with Staphylococcus aureus among the most important microorganisms due to its rapidly evolving antimicrobial resistance. Despite all the efforts of antimicrobial stewardship, research and development of new antimicrobials are still imperative. The thiazolidine ring is considered a privileged structure for the development of new antimicrobials. This study aimed to compare the antibacterial effects of two analogue series of thiazolidine-2,4-dione and 4-thioxo-thiazolidin-2-one against multidrug-resistant Staph. aureus clinical isolates. METHODS AND RESULTS: The derivatives 1a, 2a and 2b exhibited MIC between 1-32 µg ml-1 , with time-to-kill curves showing a bactericidal effect up to 24 h. In the antibiofilm assay, the most active derivatives were able to inhibit about 90% of biofilm formation. The 4-thioxo-thiazolidine-2-one derivatives were more active against planktonic cells, while the thiazolidine-2,4-dione derivatives were able to disrupt about 50% of the preformed biofilm. In the in vivo infection model using Caenorhabditis elegans as a host, the derivatives 1a, 2a and 2b increased nematode survival with a concentration-dependent effect. Exposure of Staph. aureus to the derivatives 2a and 2b induced surface changes and decrease cell size. None of the derivatives was cytotoxic for human peripheral blood mononuclear cells (PBMC) but showed moderate cytotoxicity for L929 fibroblasts. CONCLUSION: The 5-(3,4-dichlorobenzylidene)-4-thioxothiazolidin-2-one (2b) was the most active derivative against Staph. aureus and showed higher selective indices. SIGNIFICANCE AND IMPACT OF THE STUDY: 4-thioxo-thiazolidin-2-one is a promising scaffold for the research and development of new antimicrobial drugs against multidrug-resistant Staph. aureus.

Antimicrobial Peptide Analogs From Scorpions: Modifications and Structure-Activity.

The rapid development of multidrug-resistant pathogens against conventional antibiotics is a global public health problem. The irrational use of antibiotics has promoted therapeutic limitations against different infections, making research of new molecules that can be applied to treat infections necessary. Antimicrobial peptides (AMPs) are a class of promising antibiotic molecules as they present broad action spectrum, potent activity, and do not easily induce resistance. Several AMPs from scorpion venoms have been described as a potential source for the development of new drugs; however, some limitations to their application are also observed. Here, we describe strategies used in several approaches to optimize scorpion AMPs, addressing their primary sequence, biotechnological potential, and characteristics that should be considered when developing an AMP derived from scorpion venoms. In addition, this review may contribute towards improving the understanding of rationally designing new molecules, targeting functional AMPs that may have a therapeutic application.

Anti-Inflammatory Activity of Bullfrog Oil Polymeric Nanocapsules: From the Design to Preclinical Trials.

BACKGROUND: Although bullfrog oil (BFO) exerts anti-inflammatory effects, it has undesirable properties limiting its use. METHODOLOGY: BFO nanocapsules (BFONc) were produced through nanoprecipitation, and their physicochemical and morphological properties were characterized. To evaluate the biocompatibility of the formulation, a mitochondrial activity evaluation assay was conducted, and cell uptake was assessed. The in vitro anti-inflammatory activity was evaluated by measuring reactive oxygen species (ROS), nitric oxide (NO), type-6 interleukin (IL-6), and tumor necrosis factor (TNF) levels. The in vivo anti-inflammatory effect was assessed by quantifying myeloperoxidase (MPO) levels using the carrageenan-induced paw edema model. RESULTS: BFONc showed a particle size of 233 ± 22 nm, a polydispersity index of 0.17 ± 0.03, and a zeta potential of -34 ± 2.6mV. BFONc revealed remarkable biocompatibility and did not induce changes in cell morphology. Furthermore, BFONc decreased ROS levels by 81 ± 4%; however, NO level increased by 72 ± 18%. TNF and IL-6 levels were reduced by approximately 10% and 90%, respectively. Significant in vivo anti-inflammatory activity was observed compared to dexamethasone. MPO levels were reduced up to 2 MPOs/mg. CONCLUSION: Taken together, the results pointed out the remarkable biocompatibility and anti-inflammatory effects of BFONc.

Phytol-Loaded Solid Lipid Nanoparticles as a Novel Anticandidal Nanobiotechnological Approach.

Phytol is a diterpene alcohol and can be found as a product of the metabolism of chlorophyll in plants. This compound has been explored as a potential antimicrobial agent, but it is insoluble in water. In this study, we describe a novel approach for an interesting anticandidal drug delivery system containing phytol. Different formulations of phytol-loaded solid lipid nanoparticles (SLN) were designed and tested using a natural lipid, 1,3-distearyl-2-oleyl-glycerol (TG1). Different compositions were considered to obtain three formulations with 1:10, 1:5, and 1:3 w/w phytol/TG1 ratios. All the formulations were prepared by emulsification solvent evaporation method and had their physicochemical properties assessed. The biocompatibility assay was performed in the HEK-293 cell line and the antifungal efficacy was demonstrated in different strains of Candida ssp., including different clinical isolates. Spherical and uniform SLN (<300 nm, PdI < 0.2) with phytol-loading efficiency >65% were achieved. Phytol-loaded SLN showed a dose-dependent cytotoxic effect in the HEK-293 cell line. The three tested formulations of phytol-loaded SLN considerably enhanced the minimal inhibitory concentration of phytol against 15 strains of Candida spp. Considering the clinical isolates, the formulations containing the highest phytol/TG1 ratios showed MICs at 100%. Thus, the feasibility and potential of phytol-loaded SLN was demonstrated in vitro, being a promising nanocarrier for phytol delivery from an anticandidal approach.

Supramolecular aggregates of cyclodextrins with co-solvent modulate drug dispersion and release behavior of poorly soluble corticosteroid from chitosan membranes.

In this study, the ability of different beta-cyclodextrins to facilitate homogeneous dispersion of triamcinolone acetonide (TA) into chitosan membranes is assessed. Drug loading was assessed through atomic force microscopy (AFM), scanning electron microscopy (MEV-FEG), and X-ray diffraction analyses. Drug interactions with the co-polymer were investigated with Fourier transform infrared spectroscopy, thermal analyses. Swelling assay, and in vitro drug release experiment were used to assess TA release behavior. Undispersed particles of drug were observed to remain in the simple chitosan membranes. Hydroxypropyl-ß-cyclodextrin enabled the dispersion of TA into chitosan membranes and subsequent sustained drug release. In addition, the membrane performance as a drug delivery device is improved by adding specified amounts of the co-solvent triethanolamine. The experimental data presented in this study confirm the utility of our novel and alternative approach for obtaining a promising device for slow and controlled release of glucocorticoids, such as triamcinolone acetonide, for topical ulcerations.

Bullfrog Oil Reduces the Carrageenan-induced Edema in Wistar Rats by in vitro Reduction of Inflammatory Mediators.

Bullfrog oil (BFO) is a natural product from the adipose tissue of the amphibian Rana catesbeiana Shaw, a bio-product rich in polyunsaturated fatty acids, which claims anti-inflammatory activity. The objective of this work was to evaluate the cytotoxicity and the anti-inflammatory activity of BFO using in vivo and in vitro assays. Thus, the in vitro cytotoxicity was assessed by the MTT assay. Additionally, the in vivo anti-inflammatory activity was performed by the carrageenan-induced paw edema model in Wistar rats, followed by histological analysis. Moreover, the BFO effect on inflammatory pathways was investigated by in vitro evaluation of the nitric oxide (NO) synthesis, and type-6 interleukin (IL-6) and tumor-necrosis-factor (TNF) levels. In vivo experiments showed that BFO administered by intragastric route produced a significant anti-inflammatory effect, which was as substantial as indomethacin, the positive control. Histopathological analysis confirmed these results, showing the absence of the edema and minimal signs of inflammation in the paws of rats treated with BFO. The MTT results showed that BFO at all tested concentrations had no toxic effect against a macrophage cell line, not affecting the cell viability. In addition, after 48 hours of treatment, the BFO itself and its blend with Cetiol®-V (1:1v/v) at 200 µg.mL-1 were able to reduce the NO synthesis, and the IL-6 and TNF levels up to 35 ± 2%, 40 ± 6%, and 12 ± 3%, respectively. Therefore, these results provide unprecedented scientific evidence of the anti-inflammatory effect of BFO, suggesting its potential as a new candidate for the development of pharmaceutical products with anti-inflammatory activity.

Kalanchoe laciniata and Bryophyllum pinnatum: an updated review about ethnopharmacology, phytochemistry, pharmacology and toxicology

Abstract The species Kalanchoe laciniata (L.) DC. and Bryophyllum pinnatum (Lam) Pers. are native from Brazil and Madagascar, respectively. Both belonging to the Crassulaceae family and being widely used by population as a natural anti-inflammatory agent. These species have similar leaf morphology and for this reason, they are known by the same popular name as " saião " or " coirama ". Several studies have been published involving different parts and preparations of these species. Therefore, this review aims to provide an update overview about the traditional uses, chemical constitution, pharmacology and toxicology of K. laciniata and B. pinnatum species. An extensive literature review was conducted in different scientific databases. Various chemical constituents have been identified in extracts from different parts of K. laciniata and B. pinnatum , being flavonoids the major compounds. They have been traditionally used to treat inflammation, microbial infection, pain, respiratory diseases, gastritis, ulcers, diabetes and cancer tumors. Non-clinical in vitro assays evaluated mainly the antimicrobial and antioxidant activities, while in vivo assays evaluated the leishmanicide, anti-inflammatory and immunomodulatory activities. Regarding toxicity, few studies have been conducted for the two species. The information reported in this work might contribute to the recognition of the importance of K. laciniata and B. pinnatum species, as well as to direct further studies. (AU)

Self-Assembled Benznidazole-Loaded Cationic Nanoparticles Containing Cholesterol/Sialic Acid: Physicochemical Properties, In Vitro Drug Release and In Vitro Anticancer Efficacy.

Cationic polymeric nanoparticles (NPs) have the ability to overcome biological membranes, leading to improved efficacy of anticancer drugs. The modulation of the particle-cell interaction is desired to control this effect and avoid toxicity to normal cells. In this study, we explored the surface functionalization of cationic polymethylmethacrylate (PMMA) NPs with two natural compounds, sialic acid (SA) and cholesterol (Chol). The performance of benznidazole (BNZ) was assessed in vitro in the normal renal cell line (HEK-293) and three human cancer cell lines, as follows: human colorectal cancer (HT-29), human cervical carcinoma (HeLa), and human hepatocyte carcinoma (HepG2). The structural properties and feasibility of NPs were evaluated and the changes induced by SA and Chol were determined by using multiple analytical approaches. Small (<200 nm) spherical NPs, with a narrow size distribution and high drug-loading efficiency were prepared by using a simple and reproducible emulsification solvent evaporation method. The drug interactions in the different self-assembled NPs were assessed by using Fourier transform-infrared spectroscopy. All formulations exhibited a slow drug-release profile and physical stability for more than 6 weeks. Both SA and Chol changed the kinetic properties of NPs and the anticancer efficacy. The feasibility and potential of SA/Chol-functionalized NPs has been demonstrated in vitro in the HEK-293, HepG2, HeLa, and HT-29 cell lines as a promising system for the delivery of BNZ.

Potent and Broad-Spectrum Antimicrobial Activity of Analogs from the Scorpion Peptide Stigmurin.

Scorpion venom constitutes a rich source of biologically active compounds with high potential for therapeutic and biotechnological applications that can be used as prototypes for the design of new drugs. The aim of this study was to characterize the structural conformation, evaluate the antimicrobial activity, and gain insight into the possible action mechanism underlying it, for two new analog peptides of the scorpion peptide Stigmurin, named StigA25 and StigA31. The amino acid substitutions in the native sequence for lysine residues resulted in peptides with higher positive net charge and hydrophobicity, with an increase in the theoretical helical content. StigA25 and StigA31 showed the capacity to modify their structural conformation according to the environment, and were stable to pH and temperature variation-results similar to the native peptide. Both analog peptides demonstrated broad-spectrum antimicrobial activity in vitro, showing an effect superior to that of the native peptide, being non-hemolytic at the biologically active concentrations. Therefore, this study demonstrates the therapeutic potential of the analog peptides from Stigmurin and the promising approach of rational drug design based on scorpion venom peptide to obtain new anti-infective agents.

Tailoring microstructural, drug release properties, and antichagasic efficacy of biocompatible oil-in-water benznidazol-loaded nanoemulsions.

This study explored the transition of lamellar-type liquid crystal (LLC) to biocompatible oil-in-water nanoemulsions able to modify benznidazole (BNZ) release and target the drug to cells infected with the T. cruzi parasite. Three cosolvents (2methylpyrrolidone [NMP], polyethylene glycol [POL], and propylene glycol [PRO] were tested to induce the transition of anisotropic LLC systems to isotropic nanoemulsions. Mixtures of soy phosphatidylcholine with sodium oleate stabilized the dispersions of medium chain triglyceride in water. Rheological measurements, polarized microscopy, and small angle X-ray scattering demonstrated that there is a phase transition from LLC to desired nanoemulsions. These small and narrow droplet-sized nanocarriers exhibited some advantages and promising features, such as the enhanced BNZ aqueous solubility and slow drug release rate. In vitro cell biocompatibility of formulations was assessed in the Vero E6 and SiHa cell lines. Drug-loaded nanoemulsions inhibited the epimastigote growth of the T. cruzi parasite (IC50 0.208 ±â€¯0.052 µg mL-1) and reduced its infective life form trypomastigote (IC50 0.392 ±â€¯0.107 µg mL-1). The oil-in-water nanoemulsions were demonstrated as promising biocompatible liquid drug delivery systems capable of improving the BNZ trypanocidal activity for the treatment of Chagas disease.

Development of an effective and safe topical anti-inflammatory gel containing Jatropha gossypiifolia leaf extract: Results from a pre-clinical trial in mice.

ETHNOPHARMACOLOGICAL RELEVANCE: Jatropha gossypiifolia L. (Euphorbiaceae) is a medicinal plant widely used in traditional medicine as an anti-inflammatory remedy. The topical use of the leaves and/or aerial parts of this plant as anti-inflammatory, analgesic, wound healing and anti-infective in several skin diseases is a common practice in many countries. The use of baths or dressings with this vegetal species is frequently reported in folk medicine. AIM OF THE STUDY: To evaluate the topical anti-inflammatory of aqueous extract from leaves of J. gossypiifolia and to develop a safe and effective herbal gel with anti-inflammatory potential. MATERIAL AND METHODS: First, the topical acute anti-inflammatory activity of J. gossypiifolia extract was evaluated in ear edema induced by single application of croton oil in mice. Then, a polaxamer-based gel containing J. gossypiifolia extract was developed, physicochemically characterized and evaluated in the same model of inflammation to assess whether the extract incorporation in gel would affect its anti-inflammatory potential. The best formulation was then assayed in ear edema induced by multiple applications of croton oil in mice, to evaluate its chronic anti-inflammatory potential. Inflammatory parameters evaluated included edema, nitrite concentration, mieloperoxidase (MPO) activity and oxidative damage in lipids and proteins. Finally, dermal irritation/corrosion test in mice was performed to access the safeness of the developed gel. Phytochemical characterization of J. gossypiifolia extract was performed by high performance liquid chromatography with diode array detector (HPLC-DAD) analysis. RESULTS: J. gossypiifolia showed significant acute anti-inflammatory activity in ear edema model, and this activity was significantly increased when equivalent amounts of extract was applied incorporated in the developed polaxamer gels. The gels containing different amounts of extract reduced significantly the levels of edema, nitrite and MPO enzyme in mice ears, with intensity similar to the anti-inflammatory standard drug dexamethasone. The gel containing 1.0% of extract was further evaluated and also showed significant anti-inflammatory activity in chronic inflammation test, reducing significantly ear edema, lipid peroxidation and depletion of reduced glutathione, similarly to dexamethasone. Placebo formulation as well as gel containing extract showed pH compatible to that of human skin and exhibited absence of signs of toxicity in mice, indicating the safeness of the developed product for topical use. HPLC analysis confirmed the presence of C-glycosylflavonoids (orientin, isoorientin, vitexin and isovitexin) as the major compounds of J. gossypiifolia aqueous leaf extract. CONCLUSIONS: The results demonstrate the potentiality of J. gossypiifolia gel as a promising safe and effective topical anti-inflammatory agent for treatment of cutaneous inflammatory diseases.

Getting the Jump on the Development of Bullfrog Oil Microemulsions: a Nanocarrier for Amphotericin B Intended for Antifungal Treatment.

Amphotericin B (AmB), a potent antifungal drug, presents physicochemical characteristics that impair the development of suitable dosage forms. In order to overcome the AmB insolubility, several lipid carriers such as microemulsions have been developed. In this context, the bullfrog oil stands out as an eligible oily phase component, since its cholesterol composition may favor the AmB incorporation. Thus, the aim of this study was to develop a microemulsion based on bullfrog oil containing AmB. Moreover, its thermal stability, antifungal activity, and cytotoxicity in vitro were evaluated. The microemulsion formulation was produced using the pseudo-ternary phase diagram (PTPD) approach and the AmB was incorporated based on the pH variation technique. The antifungal activity was evaluated by determination of minimal inhibitory concentration (MIC) against different species of Candida spp. and Trichosporon asahii. The bullfrog oil microemulsion, stabilized with 16.8% of a surfactant blend, presented an average droplet size of 26.50 ± 0.14 nm and a polydispersity index of 0.167 ± 0.006. This system was able to entrap AmB up to 2 mg mL-1. The use of bullfrog oil as oily phase allowed an improvement of the thermal stability of the system. The MIC assay results revealed a growth inhibition for different strains of Candida spp. and were able to enhance the activity of AmB against T. asahii. The microemulsion was also able to reduce the AmB toxicity. Finally, the developed microemulsion showed to be a suitable system to incorporate AmB, improving the system's thermal stability, increasing the antifungal activity, and reducing the toxicity of this drug.

Comparison of two Jatropha species (Euphorbiaceae) used popularly to treat snakebites in Northeastern Brazil: Chemical profile, inhibitory activity against Bothrops erythromelas venom and antibacterial activity.

ETHNOPHARMACOLOGICAL RELEVANCE: Jatropha species (Euphorbiaceae) are largely used in traditional medicine to treat different pathologies in Africa, Asia and Latin America. In Northeastern Brazilian folk medicine, several Jatropha species, such as Jatropha gossypiifolia L. and Jatropha mollissima (Pohl) Baill., are indistinctly used to treat snakebites. AIM OF THE STUDY: To compare two of the Brazilian most used Jatropha species for snakebites (J. gossypiifolia and J. mollissima), in relation to their ability to inhibit local edematogenic activity of Bothrops erythromelas snake venom in mice, their in vitro antibacterial activity and phytochemical profile. MATERIAL AND METHODS: Aqueous leaf extracts of J. gossypiifolia (AEJg) and J. mollissima (AEJm) were prepared by decoction. AEJg and AEJm were compared chemically, by thin layer chromatography (TLC) and high-performance liquid chromatography with diode array detection (HPLC-DAD) analysis. They were also pharmacologically compared, using the mouse model of paw edema induced by Bothrops erythromelas snake venom (BeV), and in vitro by broth microdilution and agar dilution antimicrobial tests. RESULTS: Flavonoids were detected as the major compounds in both extracts. However, AEJg and AEJm showed quantitatively different chemical profiles by HPLC-DAD. AEJg presented fewer peaks of flavonoids than AEJm, however, when the intensity of peaks were analyzed, these compounds were at high concentration in AEJg, even using the same concentration of both extracts. Differences were also observed in the biological activity of the two extracts. While no difference was observed when the extracts were administered by oral route (P > 0.05), by the intraperitoneal route AEJg presented anti-edematogenic activity significantly (P < 0.001) higher than AEJm. In antimicrobial assays, only AEJg presented antibacterial activity against Staphylococcus epidermidis, Staphylococcus aureus and Bacillus cereus. CONCLUSIONS: Although used indistinctly by folk medicine, our results suggested that AEJg is more active than AEJm in relation to its antiedematogenic and antibacterial activities. Significant differences were observed in their phytochemical profiles, especially a higher content of C-glycosylated flavonoids in the most active species, which could justify the different biological effects observed. These findings strengthen the potentiality of J. gossypiifolia species for use as complementary treatment for local effects induced by Bothrops venoms and could be helpful for distinction of the species and control quality assessment of future herbal medicines based on Jatropha plants.

Monitoring structural features, biocompatibility and biological efficacy of gamma-irradiated methotrexate-loaded spray-dried microparticles.

In this study, biodegradable and biocompatible gamma irradiated poly-(dl-lactide-co-glycolide) (PLGA) spray-dried microparticles were prepared aiming to improve the efficacy of methotrexate (MTX). The experimental design included three formulations of microparticles containing distinct drug amount (9%, 18%, and 27% w/w) and three distinct gamma irradiation dose (15kGy, 25kGy, and 30kGy). The physicochemical and drug release properties of the microparticles supported their biocompatibility and biological efficacy studies in different cell lines. The irradiation induced slight changes in the spherical shape of the microparticles and the formation of free radicals was dependent on the drug loading. However, the amorphous character, particle size, drug loading, and drug release rate of the microparticles were preserved. The drug release data from all microparticles formulation were evaluated by using four drug kinetic models and by comparison of their similarity factor (f2). The gamma irradiation did not induce changes in the biocompatibility of PLGA microparticles and in the biological activity of the MTX-loaded microparticles. Finally, the spray-dried MTX-loaded PLGA microparticles enhanced the efficacy of the drug in the human cervical cancer cells (SiHa cell line). This study demonstrated the feasibility of the gamma irradiated spray dried PLGA microparticles for prolonged release of MTX, supporting a promising antitumor-drug delivery system for parenteral (subcutaneous) or pulmonary use.

Designing structural features of novel benznidazole-loaded cationic nanoparticles for inducing slow drug release and improvement of biological efficacy.

Several polymers have been investigated for producing cationic nanocarriers due to their ability to cross biological barriers. Polycations such as copolymers of polymethylmethacrylate are highlighted due to their biocompatibility and low toxicity. The purpose of this study was to produce small and narrow-sized cationic nanoparticles able to overcome cell membranes and improve the biological activity of benznidazole (BNZ) in normal and cancer cells. The effect of composition and procedure parameters of the used emulsification-solvent evaporation method were controlled for this purpose. The experimental approach included particle size, polydispersity index, zeta potential, atomic force microscopy (AFM), attenuated total reflectance Fourier transforms infrared spectroscopy (ATR- FTIR), drug loading efficiency, and physical stability assays. Spherical and stable (over six weeks) sub 150nm cationic nanoparticles were optimized, with the encapsulation efficiency >80%. The used drug/copolymer ratio modulated the slow drug release, which was adjusted by the parabolic diffusion mathematical model. In addition, the ability of the cationic nanoparticles improve the BNZ uptake in the normal kidney cells (HEK 293) and the human colorectal cancer cells (HT 29) demonstrate that this novel BNZ-loaded cationic has great potential as a chemotherapeutic application of benznidazole.

Structure and in vitro activities of a Copper II-chelating anionic peptide from the venom of the scorpion Tityus stigmurus.

Anionic Peptides are molecules rich in aspartic acid (Asp) and/or glutamic acid (Glu) residues in the primary structure. This work presents, for the first time, structural characterization and biological activity assays of an anionic peptide from the venom of the scorpion Tityus stigmurus, named TanP. The three-dimensional structure of TanP was obtained by computational modeling and refined by molecular dynamic (MD) simulations. Furthermore, we have performed circular dichroism (CD) analysis to predict TanP secondary structure, and UV-vis spectroscopy to evaluate its chelating activity. CD indicated predominance of random coil conformation in aqueous medium, as well as changes in structure depending on pH and temperature. TanP has chelating activity on copper ions, which modified the peptide's secondary structure. These results were corroborated by MD data. The molar ratio of binding (TanP:copper) depends on the concentration of peptide: at lower TanP concentration, the molar ratio was 1:5 (TanP:Cu2+), whereas in concentrated TanP solution, the molar ratio was 1:3 (TanP:Cu2+). TanP was not cytotoxic to non-neoplastic or cancer cell lines, and showed an ability to inhibit the in vitro release of nitric oxide by LPS-stimulated macrophages. Altogether, the results suggest TanP is a promising peptide for therapeutic application as a chelating agent.

Tailoring Drug Release Properties by Gradual Changes in the Particle Engineering of Polysaccharide Chitosan Based Powders.

Chitosan is a natural copolymer generally available in pharmaceutical and food powders associated with drugs, vitamins, and nutraceuticals. This study focused on monitoring the effect of the morphology and structural features of the chitosan particles for controlling the release profile of the active pharmaceutical ingredient (API) propranolol hydrochloride. Chitosan with distinct molecular mass (low and medium) were used in the formulations as crystalline and irregular particles from commercial raw material, or as spherical, uniform, and amorphous spray-dried particles. The API⁻copolymer interactions were assessed when adding the drug before (drug-loaded particles) or after the spray drying (only mixed with blank particles). The formulations were further compared with physical mixtures of the API with chitin and microcrystalline cellulose. The scanning electron microscopy (SEM) images, surface area, particle size measurements, X-ray diffraction (XRD) analysis and drug loading have supported the drug release behavior. The statistical analysis of experimental data demonstrated that it was possible to control the drug release behavior (immediate or slow drug release) from chitosan powders using different types of particles.