Evaluation of antioxidant and anticancer effects of Piper betle L (Piperaceae) leaf extract on MCF-7 cells, and preparation of transdermal patches of the extract

Purpose: To determine the antioxidant and anticancer effects of Piper betle (P. betle) leaf extract on human breast cancer MCF-7 cells, and to develop transdermal patches containing the extract. Methods: The leaf extract of P. betle was prepared by maceration method, and its antioxidant activity was evaluated using 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay. Cytotoxicity and suppression of cell migration (indices of anticancer activity) were also assessed in MCF-7 cells by sulforhodamine B (SRB) and wound healing assays, respectively. Transdermal patches were developed using the casting method, and the resultant patches were evaluated with regard to their physical appearance and mechanical properties before and after a stability test. Results: The extract exhibited antioxidant activity with half-maximal inhibitory concentration (IC50) of 30.0 ± 0.1 µg/mL. It also showed cytotoxicity with an IC50 of 114.3 ± 14.9 µg/mL, and significantly suppressed the migration of MCF-7 cells at a dose of 25 µg/mL. Based on desirable characteristics, patch base formulations containing 4.2 % pectin, 0.4 % hydroxyl propyl methylcellulose (HPMC), 0.4 % polyvinyl pyrrolidine K-90 (PVP-K90) and 3 % propylene glycol (PG) were selected for incorporation into the extract. Conclusion: Leaf extract of P. betle exhibits potential anti-breast cancer properties. A transdermal patch containing 0.03 % of the extract can be successfully developed for treatment of breast cancer.

Cytotoxic, colony formation and anti-migratory effects of <I>Spilanthes acmella</I> (Asteraceae) aerial extract on MCF-7 cells and its cream formulation

Purpose: To determine anti-breast cancer activities of Spilanthes acmella (S. acmella) extract.Methods: S. acmella was macerated with 95% ethanol. Phenolic, flavonoid content and antioxidant activity of the extract were assessed using Folin  Ciocalteu method, aluminum chloride (AlCl3) colorimetric method and 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, respectively. Cytotoxicity, colony formation and cell migration suppression on MCF-7 cells, representing anti-breast cancer effects, were also evaluated by sulforhodamine B (SRB), clonogenic and wound healing assays, respectively. Creams containing the extract were formulated and then characterized in terms of their physical appearance, viscosity and pH, before and after stability testing.Results: The crude extract contained phenolic content of 62.8 ± 5.2 mg gallic acid equivalent/g and flavonoid content of 375.6 ± 20.1 mg rutin equivalent/g. The results showed that the extract exhibits antioxidant effect with half-maximal inhibitory concentration (IC50) of 1.2 ± 0.1 mg/mL. It showed cytotoxicity on MCF-7 cells with IC50 of 37.1 ± 1.1 μg/mL in 48 h and inhibited colony formation of cells with IC50 of 44.9 ± 1.3 μM. In addition, it demonstrated an anti-migration effect at a concentration of 50 μg/mL. The developed creams displayed good physical appearance and maintained stable physical properties overt a two-month period. Conclusion: S. acmella extract exhibits potential anti-breast cancer activity. The cream containing the extract is promising for the topical treatment of breast cancer. Keywords: Spilanthes acmella, Antioxidant, Anti-breast cancer, Flavonoids, Phenolics, Topical cream

Suppression of inflammatory mediators and matrix metalloproteinase (MMP)-13 by Morus alba stem extract and oxyresveratrol in RAW 264.7 cells and C28/I2 human chondrocytes

This study aimed to investigate the effects of Morus alba stem extract (MSE) and oxyresveratrol on the suppression of pro-inflammatory mediators in LPS-stimulated RAW 264.7 macrophages and IL-1β-stimulated C28/I2 human chondrocyte cell line. The chondroprotective effect was also investigated using the chondrocyte cell line. First, MSE was prepared and analyzed for the amount of oxyresveratrol. The anti-inflammatory effects of MSE at various concentrations were evaluated through the inhibition of nitric oxide (NO), prostaglandin (PG)-E₂ and cyclooxygenase (COX)-2 production. Oxyresveratrol at the equivalent amount found in the extract was investigated in the same manner. The chondroprotective effect was investigated through the suppression of MMP-13 production. The results showed that oxyresveratrol content in MSE was 15%. In RAW 264.7 cells, MSE (5-50 μg/mL) could inhibit the NO (24-30%) and PGE₂ (11-82%) production. Oxyresveratrol at 0.75 and 7.5 μg/mL could suppress NO and also inhibited PGE₂ but at only at high concentration. In the chondrocyte cell line, MSE at 5-100 μg/mL significantly decreased the PGE₂ and COX-2 production by 44-93% and 17-65%, respectively. Again, oxyresveratrol at both concentrations could significantly inhibit PGE₂ production by 50-92% but it inhibited COX-2 only at high concentration. In addition, MSE and oxyresveratrol was shown to significantly inhibit MMP-13 production by 14-57% and 16-56%, depending on their concentrations. The MSE demonstrates the potential to be used as an alternative treatment for reducing inflammation and preventing cartilage degradation. Its component, oxyresveratrol, may exert these effects to some extent.

Method for screening sunscreen cream formulations by determination of in vitro SPF and PA values using UV transmission spectroscopy and texture profile analysis

Formulation of sunscreen products to obtain high values of sun protection factor (SPF) and protection from ultraviolet A (PA) is challenging work for cosmetic chemists. This study aimed to study factors affecting SPF and PA values using ultraviolet transmission spectroscopy as well as texture profiles of sunscreen formulations using 23 factorial designs. Results demonstrate that the correlation coefficient between the labeled SPF values of counter-brand sunscreen products and the in vitro SPF values was 0.901. In vitro SPF determination showed that the combination effect of phase volume ratio (PVR) and xanthan gum caused a significant increase to the SPF values of the formulations, whereas the interaction effect between PVR and stearic acid significantly decreased the SPF value. In addition, there was the interaction effect between xanthan gum and stearic acid leading to significant reduction of hardness, compressibility, and pH, but significantly increasing the adhesiveness. All tested factors did not significantly affect the cohesiveness of tested formulations. In conclusion, apart from sunscreen agents, the other ingredients also affected the SPF and PA values. The calculated SPF values range from 21 to 60. However, a selected formulation needs to be confirmed by the standard method of testing. In addition, the physical, chemical, and biological stability; shelf life; and sensory evaluation of all formulations need to be evaluated.

Polymeric micelles of PEG-PE as carriers of all-trans retinoic acid for stability improvement

The topical application of all-trans retinoic acid (ATRA) is an effective treatment for several skin disorders, including photo-aging. Unfortunately, ATRA is susceptible to light, heat, and oxidizing agents. Thus, this study aimed to investigate the ability of polymeric micelles prepared from polyethylene glycol conjugated phosphatidylethanolamine (PEG-PE) to stabilize ATRA under various storage conditions. ATRA entrapped in polymeric micelles with various PEG and PE structures was prepared. The critical micelle concentrations were 97-243 μM, depending on the structures of the PEG and PE molecules. All of the micelles had particle diameters of 6-20 nm and neutral charges. The highest entrapment efficiency (82.7%) of the tested micelles was exhibited by ATRA in PEG with a molecular weight of 750 Da conjugated to dipalmitoyl phosphatidylethanolamine (PEG(750)-DPPE) micelles. The PEG(750)-DPPE micelle could significantly retard ATRA oxidation compared to ATRA in 75% methanol/HBS solution. Up to 87% of ATRA remained in the PEG(750)-DPPE micelle solution after storage in ambient air for 28 days. This result suggests that PEG(750)-DPPE micelle can improve ATRA stability. Therefore, ATRA in PEG(750)-DPPE micelle is an interesting alternative structure for the development of cosmeceutical formulations.

Chitosan and trimethyl chitosan chloride (TMC) as adjuvants for inducing immune responses to ovalbumin in mice following nasal administration

Chitosan of different molecular weights (Chi-P, MW=2.7x10(5) g/mol and Chi-A, MW=5.0x10(5) g/mol) and trimethyl chitosan chloride (TMC) of various degree of quaternization (DQ) including TMC-20, TMC-40 and TMC-60 were evaluated as adjuvants for inducing of immune responses to ovalbumin (OVA). OVA in solution and in alum were used as controls. Groups of BALB/c mice were immunized on days 0, 7 and 14. The IgG and IgA titers were examined on days 0, 13 and 21. It was found that for both days 13 and 21, Chi-A could elicit higher IgG responses to OVA than Chi-P. On day 13, OVA in TMC-40 induced IgG responses significantly higher than that in solution, Chi-P and TMC-60. Moreover, OVA in TMC-40 could induce IgG responses higher than OVA in alum. Although a significant difference was not observed at day 21, OVA in TMC-40 was shown to induce higher IgG responses than that in TMC-20, TMC-60 and solution. The IgA responses were the most pronounced on day 21. Again, Chi-A could elicite higher IgA responses than Chi-P and TMC-40 induced the highest IgA responses. In conclusion, these findings demonstrate that both MW of chitosan and DQ of TMC influence the level of immune induction. TMC-40 shows to be the most potent adjuvant for intranasal administration.

Targeted transfollicular delivery of artocarpin extract from Artocarpus incisus by means of microparticles

Artocarpin (Ar), an extract of heartwood of Artocarpus incisus, possesses potent 5alpha reductase inhibitory effect. The penetration of Ar into the deeper layers of the skin where androgen receptors are present is limited. Therefore, this study was aimed to prepare alginate/chitosan (ACS) microparticles for targeted transfollicular delivery. It was found that a suitable particle size ranging from 2 to 6 microm can be prepared using the ionotropic gelation technique. Entrapment efficiency of Ar in ACS microparticles was 18.7+/-1.7%. The release of Ar from the ACS microparticles over 6 h was 0.7% of the loading dose suitable for a long-term release of Ar in the follicular ducts. The optimal growth suppression of the hamster flank organs could be achieved by topical application of Ar-ACS microparticles with a content of 0.1 mg in 5 mg microparticles to one hamster flank while the other flank (intraspecies control) showed the normal growth of the flank organs and Ar at the same concentration in solution form could not suppress the growth of the flank organs to the same extent. The efficiency of Ar 0.1 mg loaded in ACS microparticles was shown to be comparable to a dose of 1 mg Ar applied as solution. However, Ar formulated in microparticles did not show significant systemic action compared to the dermal application of an Ar solution and a flutamide preparation (1 mg) as positive control.

Effect of degree of esterification of pectin and calcium amount on drug release from pectin-based matrix tablets

The aim of this work was to assess the effect of 2 formulation variables, the pectin type (with different degrees of esterification [DEs]) and the amount of calcium, on drug release from pectin-based matrix tablets. Pectin matrix tablets were prepared by blending indomethacin (a model drug), pectin powder, and various amounts of calcium acetate and then tableting by automatic hydraulic press machine. Differential scanning calorimetry, powder x-ray diffraction, and Fourier transformed-infrared spectroscopy studies of the compressed tablets revealed no drug-polymer interaction and the existence of drug with low crystallinity. The in-vitro release studies in phosphate buffer (United States Pharmacopeia) and tris buffer indicated that the lower the DE, the greater the time for 50% of drug release (T50). This finding is probably because of the increased binding capacity of pectin to calcium. However, when the calcium was excluded, the pectins with different DEs showed similar release pattern with insignificant difference of T50. When the amount of calcium acetate was increased from 0 to 12 mg/tablet, the drug release was significantly slower. However, a large amount of added calcium (ie, 24 mg/tablet) produced greater drug release because of the partial disintegration of tablets. The results were more pronounced in phosphate buffer, where the phosphate ions induced the precipitation of calcium phosphate. In conclusion, both pectin type and added calcium affect the drug release from the pectin-based matrix tablets.

Uptake of antigen encapsulated in polyethylcyanoacrylate nanoparticles by D1-dendritic cells

Polyethylcyanoacrylate (PECA) nanoparticles were prepared by interfacial polymerization of a water-in-oil microemulsion. Nanoparticles were isolated from the polymerization template by sequential ethanol washing and centrifugation. A nanocapsule preparation yielding the original particle size and distribution following redispersion in an aqueous solution was achieved by freeze-drying the isolated nanoparticles in a solution of 5% w/v sugar. The cytotoxicity and uptake of nanocapsules by dendritic cells was investigated using a murine-derived cell line (D1). PECA nanoparticles were found to adversely effect cell viability at concentrations greater than 10 microg/ml of polymer in the culture medium. In comparison to antigen in solution, cell uptake of antigen encapsulated within nanoparticles was significantly higher at both 4 and 37 degrees C. Following a 24 h incubation period, the percentage of cells taking-up antigen was also increased when antigen was encapsulated in nanoparticles as compared to antigen in solution. The uptake of nanoparticles and the effect of antigen formulation on morphological cell changes indicative of cell maturation were also investigated by scanning electron microscopy (SEM). SEM clearly demonstrated the adherence of nanoparticles to the cell surface. Incubation of D1 dendritic cells with nanoparticles containing antigen also resulted in morphological changes indicative of cell maturation similar to that observed when the cells were incubated with lipopolysaccharide. In contrast, cells incubated with antigen solution did not demonstrate such morphological changes and appeared similar to immature cells that had not been exposed to antigen.

Factors influencing the entrapment of hydrophilic compounds in nanocapsules prepared by interfacial polymerisation of water-in-oil microemulsions

This study demonstrates the effect of drug properties and method of loading (sorption and encapsulation) on entrapment within poly(alkyl cyanoacrylate) nanocapsules prepared by interfacial polymerisation of biocompatible water-in-oil microemulsions. For small molecular weight compounds (<1000 Da), entrapment efficiency is more dependent on charge of the compound than on the method used for entrapment. Entrapment efficiency within the negatively charged nanocapsules (zeta potential approximately -30 mV) was in the order cationic compound > neutral compound > anionic compound. Only minimal differences for entrapment efficiency were noted between sorption (addition of the compound 4 h after initiation of the polymerisation) and encapsulation (addition of the compound to microemulsion prior to polymerisation). For high molecular weight compounds, the method used for entrapment however, is very important. For hydrophilic macromolecules such as proteins, high entrapment efficiencies can only be achieved by encapsulation. Entrapment of such compounds seems to be independent of the net charge of the compound being encapsulated but depended on the molecular weight. For nanocapsules prepared by interfacial polymerisation of water-in-oil microemulsions, these findings are useful as a foundation in the development of nanocapsules with desired properties.

Studies on pectins as potential hydrogel matrices for controlled-release drug delivery

Polymeric hydrogels are widely used as controlled-release matrix tablets. In the present study, we investigated high-methoxy pectins for their potential value in controlled-release matrix formulations. The effects of compression force, ratio of drug to pectin, and type of pectin on drug release from matrix tablets were also investigated. The results of the in vitro release studies show that the drug release from compressed matrix tablets prepared from pectin can be modified by changing the amount and the type of pectin in the matrix tablets. However, compression force did not significantly affect the drug release. The mechanisms controlling release rate were discussed with respect to drug diffusion through the polymer matrices, but may be more complex.