Encapsulation of Piper cabralanum (Piperaceae) nonpolar extract in poly(methyl methacrylate) by miniemulsion and evaluation of increase in the effectiveness of antileukemic activity in K562 cells

Ephedra intermedia Schrenk & C. A. Mey Methanol Extract: Nanoencapsulation by Mini-Emulsion Polymerization and its Release Trend under Simulated Conditions of the Human Body

In this research, the extract of Ephedra intermedia Schrenk & C.A.Mey. was encapsulated using the mini-emulsion polymerization method based on methyl methacrylate polymers with a nanometer size. The encapsulated extract was characterized using different analytical techniques. Furthermore, the loading efficiency and release of the plant extract were examined. FT-IR spectroscopy confirmed the formation of an expectational product. The TEM and SEM imaging showed a spherical morphology for the prepared encapsulated extract. The average size of poly-methyl-methacrylate nanoparticles containing Ephedra extract was found to be approximately 47 nm. The extract loading efficiency and encapsulation efficiency test demonstrated a dose-depending behavior on E. intermedia extract for both analyses, which is highly advantageous for traversing biological barriers. The release assay shows a controlled release for the extract at phosphate buffer solution (PBS). A 38 % release was calculated after 36 hours. The results obtained from the present study reveal that encapsulating the plant extract is a suitable alternative to control and increase their medicinal properties.

Toxicogenetic profile of the monoterpene alpha-terpineol on normal and tumor eukaryotic cells

Alpha-terpineol is a monoterpene alcohol found in essential oils from medicinal plants with some well-known pharmacological activities and widely used in cosmetics. However, the toxicological effects and additional pharmacological activities need to be clarified. Thus, the study evaluated the toxic, cytotoxic, genotoxic, hemolytic, and oxidative potential of alpha-terpineol in non-clinical bioassays. Different concentrations of alpha-terpineol were used in bioassays, including MTT (50, 100, 200, and 400 μg/mL), Artemia salina (6.25-400 μg/mL), Allium cepa (10, 50, and 100 μg/mL), comet assay (100, 200, and 500 μg/mL), cytokinesis-block micronucleus (100, 250, and 500 μg/mL), confocal microscopy for apoptosis quantification (100 and 500 μg/mL), hemolysis and Saccharomyces cerevisiae central disk test (10, 35, and 75 μg/mL). For the MTT test, alpha-terpineol was more cytotoxic on melanoma murine B16-F10 cells rather than macrophages. For A. salina test, alpha-terpineol showed LC₅₀ of 68.29 and 76.36 μg/mL for 24 h and 48 h of exposure time, respectively. Meanwhile, alpha-terpineol was also cytotoxic to meristematic cells, which revealed inhibition of cellular division and mutagenic action by formation of bridges and delayed anaphases. The compound increased damage index and frequency of damage corroborated by the presence of micronuclei, bridges and nuclear buds at 500 μg/mL, but it caused neither hemolysis, oxidative damage on the S. cerevisiae nor cell death in normal fibroblasts. The findings indicate alpha-terpineol has cytotoxic potential by cytogenetic and molecular mechanisms associated with apoptosis and probable target effects against melanoma cells.

Films composed of white angico gum and chitosan containing chlorhexidine as an antimicrobial agent

Anadenanthera colubrina, popularly known as white angico, is a species extensively cultivated in Brazil, mainly in the cerrado region, including the state of Piauí. This study examines the development of films composed of white angico gum (WAG) and chitosan (CHI) and containing chlorhexidine (CHX), an antimicrobial agent. The solvent casting method was used to prepare films. Different combinations and concentrations of WAG and CHI were used to obtain films with good physicochemical characteristics. Properties such as the in vitro swelling ratio, the disintegration time, folding endurance, and the drug content were determined. The selected formulations were characterised by scanning electron microscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and X-ray diffraction, and the CHX release time and antimicrobial activity were evaluated. CHX showed a homogenous distribution in all CHI/WAG film formulations. The optimised films showed good physicochemical properties with 80% CHX release over 26 h, which is considered promising for local treatment of severe lesions in the mouth. Cytotoxicity tests of the films did not show toxicity. The antimicrobial and antifungal effects were very effective against the tested microorganisms.

Antiulcerogenic and Antibacterial Effects of Chitosan Derivatives on Experimental Gastric Ulcers in Rats

Gastric ulcer is an injury that develops on the lining of the stomach due to an imbalance between aggressive and defensive agents. Chitosan derivatives demonstrate promising biological activities in accelerating the healing activity of gastric lesions. Thus, this study aimed at investigating the healing activity of gastric lesion, induced by acetic acid (80%), of the chitosan derivative with acetylacetone (Cac) modified with ethylenediamine (Cacen) or diethylenetriamine (Cacdien). The biological activity was determined based on cytotoxicity, antibacterial activity, and gastroprotective activities. The results showed no significant difference in the cytotoxicity, a better antibacterial activity against S. aureus and E. coli, and a positive result on the healing of gastric lesions of the materials (Cac 18.4%, Cacen 55.2%, and Cacdien 68.1%) compared to pure chitosan (50.7%). Therefore, the results indicate that derivatives of chitosan are promising biomaterials for application in the control of lesions on the gastric mucosa.

Fabrication and characterization of Agarwood extract-loaded nanocapsules and evaluation of their toxicity and anti-inflammatory activity on RAW 264.7 cells and in zebrafish embryos

Aquilaria malaccensis has been traditionally used to treat several medical disorders including inflammation. However, the traditional claims of this plant as an anti-inflammatory agent has not been substantially evaluated using modern scientific techniques. The main objective of this study was to evaluate the anti-inflammatory effect of Aquilaria malacensis leaf extract (ALEX-M) and potentiate its activity through nano-encapsulation. The extract-loaded nanocapsules were fabricated using water-in-oil-in-water (w/o/w) emulsion method and characterized via multiple techniques including DLS, TEM, FTIR, and TGA. The toxicity and the anti-inflammatory activity of ALEX-M and the extract-loaded nanocapsules (ALEX-M-PNCs) were evaluated in-vitro on RAW 264.7 macrophages and in-vivo on zebrafish embryos. The nanocapsules demonstrated spherical shape with mean particle diameter of 167.13 ± 1.24 nm, narrow size distribution (PDI = 0.29 ± 0.01), and high encapsulation efficiency (87.36 ± 1.81%). ALEX-M demonstrated high viability at high concentrations in RAW 264.7 cells and zebrafish embryos, however, ALEX-M-PNCs showed relatively higher cytotoxicity. Both free and nanoencapsulated extract expressed anti-inflammatory effects through significant reduction of the pro-inflammatory mediator nitric oxide (NO) production in LPS/IFNγ-stimulated RAW 264.7 macrophages and zebrafish embryos in a concentration-dependent manner. The findings highlight that ALEX-M can be recognized as a potential anti-inflammatory agent, and its anti-inflammatory activity can be potentiated by nano-encapsulation. Further studies are warranted toward investigation of the mechanistic and immunomodulatory roles of ALEX-M.

Anti-Leishmania activity of extracts from Piper cabralanum C.DC. (Piperaceae)

Species of Piperaceae are known by biological properties, including antiparasitic such as leishmanicidal, antimalarial and in the treatment of schistosomiasis. The aim of this work was to evaluate the antileishmania activity, cytotoxic effect, and macrophage activation patterns of the methanol (MeOH), hexane (HEX), dichloromethane (DCM) and ethyl acetate (EtOAc) extract fractions from the leaves of Piper cabralanum C.DC. The MeOH, HEX and DCM fractions inhibited Leishmanina amazonensis promastigote-like forms growth with a half maximal inhibitory concentration (IC₅₀) of 144.54, 59.92, and 64.87 μg/mL, respectively. The EtOAc fraction did not show any relevant activity. The half maximal cytotoxic concentration (CC₅₀) for macrophages were determined as 370.70, 83.99, 113.68 and 607 μg/mL for the MeOH, HEX and DCM fractions, respectively. The macrophage infectivity was concentration-dependent, especially for HEX and DCM. MeOH, HEX and DCM fractions showed activity against L. amazonensis with low cytotoxicity to murine macrophages and lowering infectivity by the parasite. Our results provide support for in vivo studies related to a potential application of P. cabralanum extract and fractions as a promising natural resource in the treatment of leishmaniasis.

Well Defined Poly(Methyl Methacrylate)-Fe3O4/Poly(Vinyl Pivalate) Core-Shell Superparamagnetic Nanoparticles: Design and Evaluation of In Vitro Cytotoxicity Activity Against Cancer Cells

The objective of this work is to develop and characterize polymeric nanoparticles with core-shell morphology through miniemulsion polymerization combined with seeded emulsion polymerization, aiming at the application in the treatment of vascular tumors via intravascular embolization. The synthesis of the core-shell nanocomposites was divided into two main steps: (i) Formation of the core structure, consisting of poly(methyl methacrylate)/magnetic oxide coated with oleic acid (OM-OA) via miniemulsion and (ii) shell structure produced through seeded emulsion polymerization of vinyl pivalate. Nanocomposites containing about 8 wt.% of OM-OA showed high colloidal stability, mean diameter of 216.8 nm, spherical morphology, saturation magnetization (Ms) of 4.65 emu·g-1 (57.41 emu·g-1 of Fe3O4), preserved superparamagnetic behavior and glass transition temperature (Tg) of 111.8 °C. TEM micrographs confirmed the obtaining of uniformly dispersed magnetic nanoparticles in the PMMA and that the core-shell structure was obtained by seeded emulsion with Ms of 1.35 emu·g-1 (56.25 emu·g-1 of Fe3O4) and Tg of 114.7 °C. In vitro cytotoxicity assays against murine tumor of melanoma (B16F10) and human Keratinocytes (HaCaT) cell lines were carried out showing that the core-shell magnetic polymeric materials (a core, consisting of poly(methyl methacrylate)/Fe3O4 and, a shell, formed by poly(vinyl pivalate)) presented high cell viabilities for both murine melanoma tumor cell lines, B16F10, and human keratinocyte cells, HaCaT.

Biological evaluation, proposed molecular mechanism through docking and molecular dynamic simulation of derivatives of chitosan

We synthesized Schiff base and its complexes derivatives of chitosan (CS) in order to develop antibiotic compounds based on functionalized-chitosan against gram-positive and gram-negative bacteria. IR, UV-Vis, AFM, SEM, Melting point, X-ray diffraction (XRD), elemental analysis, and ¹H NMR techniques were employed to characterize the chemical structures and properties of these compounds. XRD, UV-Vis, and ¹H NMR techniques confirmed the formation of Schiff base and its functionalized-chitosan to metals. Subsequently, our antibacterial studies revealed that antibacterial activities of [Zn(Schiff base)(CS)] against S. aureus bacteria increased compared to those of their compounds. In addition, hemolysis test of CS-Schiff base-Cu(II) demonstrated better hemolytic activity than vitamin C, CS-Schiff base, CS-Schiff base-Zn(II), and CS-Schiff base-Ni(II). In a computational strategy, we carried out the optimization of compounds with molecular mechanics (MM⁺), Semi-emprical (AM1), Abinitio (STO-3G), AMBER, BIO+(CHARMM), and OPLS. Frontier orbital density distributions (HOMO and LUMO), and the optimized computational UV of the compounds were assessed. The optimized computational UV-Vis was similar to the experimental UV-Vis. We applied the docking methods to predict the DNA binding affinity, Staphylococcus aureus enoyl-acyl carrier protein reductase (ENRs), and Staphylococcus aureus enoyl-acyl carrier protein reductase (saFabI). Ultimately, the obtained data herein suggested that Schiff base is more selective toward ENRs and saFabI compared to chitosan, its complexes, and metronidazole.

In Vivo Antidepressant Effect of Passiflora edulis f. flavicarpa into Cationic Nanoparticles: Improving Bioactivity and Safety

A variety of neuroactive flavonoids can be found in the species of the Passiflora genus; however, their difficulty in crossing the blood-brain barrier limits their in vivo neuropharmacological activity. In this study, cationic nanoparticles were developed as a novel nanocarrier for improving the antidepressant activity of Passiflora edulis f. flavicarpa leaf extract. Formulations obtained using Eudragit E PO polymethylmethacrylate copolymer, as polymeric matrix had their physicochemical properties investigated. The analytical content of the flavonoids vicenin-2, orientin, isoorientin, vitexin, and isovitexin was determined in the plant extract. Small-sized and spherical nanoparticles loaded with Passiflora edulis f. flavicarpa were obtained with positive zeta potential and high encapsulation efficiency. In addition, the nanosystems were shown to be stable for at least 6 months. The antidepressant activity of P. edulis extract (50 and 100 mg/kg) as well as the extract-loaded nanoparticles (5 mg/kg) were investigated in mice using the forced swimming test, where the latter increased the potency of the former by 10-fold. In addition, histopathological and biochemical analysis confirmed the biocompatibility of the extract-loaded nanoparticles. This study demonstrated that the Eudragit cationic nanoparticles were able to improve the antidepressant activity of P. edulis in the central nervous system of mice.

Targeted delivery of poly (methyl methacrylate) particles in colon cancer cells selectively attenuates cancer cell proliferation

Poly (methyl methacrylate) (PMMA) is basically biocompatible polyester with high resistance to chemical hydrolysis, and high drug permeability and the most important characteristics of PMMA is that it does not produce any toxicity. There is not much information about PMMA action on the colon cancer cells. In the present study, we have synthesized PMMA nanoparticles. The distribution pattern of PMMA particles was analysed by Zeta sizer and the size of the particles was calculated by using quasi elastic light scattering (QELS). The surface structure and the morphology of PMMA were characterized by transmission electron microscope (TEM) and scanning electron microscope (SEM), respectively. We have also analysed their effects on cancerous cells (human colorectal carcinoma cells, HCT-116) and normal, healthy cells (human embryonic kidney cells, HEK-293) by using morphometric, MTT, DAPI and wound healing methods. We report that PMMA particles inhibited the cancer cell viability in a dose-dependent manner. The lower dose (1.0 μg/ml) showed a moderate decrease in cancer cell viability, whereas higher dosages (2.5 μg/ml, 5.0 μg/mL and 7.5 μg/mL) showed steadily decrease in the cancer cell viability. We also report that PMMA is highly selective to cancerous cells (HCT-116), as we did not find any action on the normal healthy cells (HEK-293). In conclusion, our results suggest PMMA particles are potential biomaterials to be used in the treatment of colon cancer.

In vitro and in vivo effect of hyaluronic acid modified, doxorubicin and gallic acid co-delivered lipid-polymeric hybrid nano-system for leukemia therapy

Objective: To investigate the hyaluronic acid (HA) modified, doxorubicin (DOX) and gallic acid (GA) co-delivered lipid-polymeric hybrid nano-system for leukemia therapy.

Methods: We produced a kind of lipid-polymer hybrid nanoparticle (LPHN) with a core-shell structure in which DOX and GA were co-loaded. In vitro and in vivo leukemia therapeutic effects of the HA modified, DOX and GA co-delivered LPHNs (HA-DOX/GA-LPHNs) were evaluated in DOX resistant human HL-60 promyelocytic leukemia cells (HL-60/ADR cells), DOX resistant human K562 chronic myeloid leukemia cells (K562/ADR cells), and HL-60/ADR cells bearing mouse model.

Results: The sizes and zeta potentials of HA modified LPHNs were about 160 nm and −40 mV. HA-DOX/GA-LPHNs showed the most prominent cytotoxicity and the best synergistic effect was obtained when DOX/GA ratio was 2/1. In vivo studies revealed that HA-DOX/GA-LPHNs inhibited tumor growth from 956 mm³ to 213 mm³, with an inhibition rate of 77.7%.

Conclusion: In summary, the study showed that HA-DOX/GA-LPHNs can be applied as a promising leukemia therapy system.

Development of nanoparticulate systems with action in breast and ovarian cancer: nanotheragnostics

The use of nanoparticulate systems with action in breast and ovarian cancer has been highlighted in recent years as an alternative to increasing the therapeutic index of conventional anticancer drugs. Thus, nanoparticles have advantageous characteristics in the treatment of cancer. Several nanocarriers of drugs and nanoparticles are described in the literature. The pharmacokinetics of the drugs can be modified by the use of nanocarriers, which in turn facilitate the specific delivery of the drug to the tumour cell. Therefore, the present work is a review that examines some nanosystems with nanoparticles for action in the treatment of breast cancer and ovarian cancer.