Drug compartmentalization as strategy to improve the physico-chemical properties of diclofenac sodium loaded niosomes for topical applications.

The objective of this research was to study the effect of diclofenac sodium compartmentalization on the physico-chemical properties (such as size, drug entrapment efficiency and percutaneous permeation across rabbit skin) of niosomal vesicles used as carriers. Niosomes were prepared starting from nonionic commercial surfactants belonging to the class of Polysorbates and Pluronics: mixtures of Span 60/F127 and Tween 60/F127 at different ratios were used to obtain vesicles and all formulations were compared in terms of dimensions, morphology, polydispersity index and entrapment efficiency. Moreover, the enhancing effect of niosomes on the ex vivo percutaneous penetration of diclofenac sodium was investigated using Franz-type diffusion chambers and compared to that obtained by using the corresponding drug solution. Results demonstrated that niosomes were spherical and homogeneous in shape. Their size was found to be dependent on the hydrophile-lipophile balance of the surfactant mixture: increasing hydrophobicity resulted in smaller vesicles. Drug incorporation led to a significant variation in vesicle size dependently from the compartment in which the drug was located. The permeation of diclofenac from free solution used as control was found to be lower respect to that obtained for all niosomal formulations, that can be considered as percutaneous permeation enhancers. In particular, the results indicated that the highest cumulative amounts of diclofenac permeated across rabbit skin after 24 h were obtained by formulations in which the drug was located in the aqueous core.

Comparative study on the chemical composition, antioxidant properties and hypoglycaemic activities of two Capsicum annuum L. cultivars (Acuminatum small and Cerasiferum).

The present study aimed to evaluate for the first time the phenols, flavonoids, carotenoids, capsaicin and dihydrocapsaicin content and the antioxidant and hypoglycemic properties of Capsicum annuum var. acuminatum small and C. annuum var. cerasiferum air-dried fruits. The ethanol extract of C. annuum var. acuminatum small, characterized by the major content of total poliphenols, flavonoids, carotenoids and capsaicinoids, showed the highest radical scavenging activity (IC(50) of 152.9 µg/ml). On the contrary, C. annuum var. cerasiferum showed a significant antioxidant activity evaluated by the ß-carotene bleaching test (IC(50) of 3.1 µg/ml). The lipophilic fraction of both C. annuum var. acuminatum and C. annuum var. cerasiferum exhibited an interesting and selective inhibitory activity against α-amylase (IC(50) of 6.9 and 20.1 µg/ml, respectively).

In vitro photo-induced cytotoxic activity of Citrus bergamia and C. medica L. cv. Diamante peel essential oils and identified active coumarins.

CONTEXT: The search for innovative therapeutic approaches is gaining more interest in clinical oncology. OBJECTIVE: In the present investigation we reported the chemical profile and the photo-induced cytotoxic activity of two endemic Calabrian Citrus species (Rutaceae): Citrus bergamia Risso & Poit. and Citrus medica L. cv. Diamante. MATERIALS AND METHODS: Essential oils were obtained by hydrodistillation and analyzed by GC and GC/MS. In order to evaluate the cytotoxic activity two melanoma models, such as amelanotic melanoma C32 and malignant melanoma A375, were used. RESULTS: The essential oil of C. bergamia was characterized by limonene, linalyl acetate, gamma-terpinene, linalool and beta-pinene as major components. The most abundant compounds of C. medica cv. Diamante oil were limonene, gamma-terpinene, citral, geranial, beta-pinene and alpha-pinene. Two coumarins, bergapten and citropten, were also identified in C. bergamia and C. medica cv. Diamante, respectively and tested for biological activity. Both C. bergamia and C. medica cv. Diamante oils exhibited a selective interesting activity against the A375 cell line with IC(50) values of 79.3 and 89.1 microg/mL, respectively, after 100 min exposure to UV irradiation. The strong antiproliferative activity demonstrated with bergapten (IC(50) value of 71.3 microg/mL after 20 min of irradiation) was not found with citropten. DISCUSSION AND CONCLUSION: Our study suggested that UV irradiation is effective in activating essential oils and in particular bergapten. This phototoxicity may be considered as a treatment option in some cases of lentigo maligna or lentigo maligna melanoma.

In vitro inhibitory activities of plants used in Lebanon traditional medicine against angiotensin converting enzyme (ACE) and digestive enzymes related to diabetes.

AIM OF THE STUDY: In recent years the use of medicinal plants has been growing worldwide and this is particularly true in Lebanon. In the present investigation we report the inhibitory activity against digestive enzymes related to diabetes and angiotensin converting enzyme (ACE) of extracts of nine plant species collected in Lebanon, where they have a traditional use against diabetes. MATERIALS AND METHODS: In order to evaluate if the extraction procedure could influence the activity we decided to perform different extractions with methanol, n-hexane and chloroform of Calamintha origanifolia, Satureja thymbra, Prangos asperula, Sideritis perfoliata, Asperula glomerata, Hyssopus officinalis, Erythraea centaurium, Marrubium radiatum and Salvia acetabulosa and test each of them. RESULTS AND CONCLUSIONS: Marrubium radiatum and Salvia acetabulosa methanol extracts exerted the highest activity against alpha-amylase (IC(50) 61.1 and 91.2 microg/ml, respectively) and alpha-glucosidase (IC(50) 68.8 and 76.9 microg/ml, respectively). The same extracts exhibited a strong inhibitory activity against ACE with IC(50) of 72.7 and 52.7 microg/ml, respectively. The results support the traditional use of some the species examined.

The blood rheology in renal pathology.

The blood is a viscoelastic material often studied as a Newtonian or non-linear liquid. Some pathologies and extracorporeal blood treatment processes may affect both the liquid and solid blood component. An adequate rheological technique, able to detect these alterations, may provide clinicians with an important diagnostic aid. Creep tests consisting in the application of a constant stress are very promising because they may roughly separate the liquid-like (i.e., at long response times) from the solid-like (i.e., at short response times) component of the blood rheological behaviour. In this paper, some preliminary results obtained in creep tests on healthy and uremic individuals are reported showing the potentiality of this technique.

The effects of intermolecular interactions on the physical properties of organogels in edible oils.

The microstructure of organogels based on monoglycerides of fatty acids (MAGs) and policosanol and on different edible oils was investigated by using different techniques (calorimetry, nuclear magnetic resonance, infrared spectroscopy, rheology, polarized light microscopy) towards a better understanding and control of the oil gelation phenomena. Dynamic moduli were related via a fractal model to microstructural information such as solid content and fractal dimension. Infrared spectroscopy evidenced that network structure in MAGs gel is mainly due to hydrogen bonding, whereas in policosanol system is mainly given by van der Waals interactions. Because of the different relative contribution of molecular interactions, the investigated organogelators exhibit a distinguished macroscopic behavior. MAGs are sensitive to the utilized oil and structuration occurs quickly, even though at a temperature lower than policosanol. Policosanol organogels exhibit a behavior independent of the used oil and a slower gelation rate, as a result of the weaker van der Waals interactions. Nevertheless, at lower concentration a stronger final gel is obtained, probably due to of the large number of interactions arising among the long alkyl chains of the fatty alcohols. Obtained results evidenced that policosanol is very effective in gelation of different oils and seems promising for potential commercial uses.

Co-encapsulation of antioxidants into niosomal carriers: gastrointestinal release studies for nutraceutical applications.

Recently niosomes have been used as nutraceutical vehicles of functional components, useful in the prevention of many diseases caused by oxidative stress, with the aim to control their delivery into the body and to increase the nutritional quality of food dairy products with which these products can be enriched. We decided to develop novel niosomal formulations containing nutritional supplements such as gallic acid, ascorbic acid, curcumin and quercetin as single agents and in combination, to evaluate the effect of the active molecules co-encapsulation on the physico-chemical properties of the carriers, on their antioxidant properties and capability of releasing the encapsulated materials. Results suggest that the co-encapsulations of gallic acid/curcumin and ascorbic acid/quercetin mix influence their physico-chemical properties and their entrapment efficiencies respect to the formulations containing the single antioxidant; also the antioxidants releases appeared to improve and their combinations resulted in a promoted ability of reducing free radicals, due to a synergic antioxidant action.

Co-encapsulation of lipophilic antioxidants into niosomal carriers: percutaneous permeation studies for cosmeceutical applications.

Niosomal vesicular systems containing resveratrol, alpha-tocopherol and curcumin as single agents and in combination, were designed with the aim to develop novel cosmeceutical formulations. The effects of antioxidants co-encapsulation on the physico-chemical properties of the carriers, their antioxidant properties and in vitro percutaneous permeation profiles were evaluated. Results showed that the co-encapsulation of resveratrol/curcumin and alpha-tocopherol/curcumin affected the physico-chemical properties of niosomes and the entrapment efficiencies values, respect to the formulations containing the single antioxidant. The antioxidants in vitro percutaneous permeations appeared to be controlled and improved respect to the corresponding free solutions used as control. Moreover the antioxidants combinations resulted in a promoted ability to reduce free radicals, due to a synergic antioxidant action.

Malvidin, a red wine polyphenol, modulates mammalian myocardial and coronary performance and protects the heart against ischemia/reperfusion injury.

A moderate red wine consumption and a colored fruit-rich diet protect the cardiovascular system, thanks to the presence of several polyphenols. Malvidin-3-0-glucoside (malvidin), an anthocyanidine belonging to polyphenols, is highly present in red grape skin and red wine. Its biological activity is poorly characterized, although a role in tumor cell inhibition has been found. To analyze whether and to which extent, like other food-derived polyphenols, malvidin affects the cardiovascular function, in this study, we have performed a quantitative analysis by high-performance liquid chromatography of polyphenolic content of red grape skins extract, showing that it contains a high malvidin amount (63.93 ±12.50 mg/g of fresh grape skin). By using the isolated and Langendorff perfused rat heart, we found that the increasing doses (1-1000 ng/ml) of the extract induced positive inotropic and negative lusitropic effects associated with coronary dilation. On the same cardiac preparations, we observed that malvidin (10(-10)-10(-6) mol/L) elicited negative inotropism and lusitropism and coronary dilation. Analysis of mechanism of action revealed that malvidin-dependent cardiac effects require the activation of the phosphatidylinositol 3-kinase (PI3K)/nitric oxide (NO)/cGMP/PKG pathway and are associated with increased intracellular cGMP and the phosphorylation of endothelial NO synthase (eNOS), PI3K-AKT, ERK1/2, and GSK-3ß. AKT and eNOS phosphorylation was confirmed in human umbilical vein endothelial cell. We also found that malvidin act as a postconditioning agent, being able to elicit cardioprotection against ischemia/reperfusion damages. Our results show the cardioactivity of polyphenols-rich red grape extracts and indicate malvidin as a new cardioprotective principle. This is of relevance not only for a better clarification of the beneficial cardiovascular effects of food-derived polyphenols but also for nutraceutical research.

Niosomes vs microemulsions: new carriers for topical delivery of Capsaicin.

The development of advanced biomaterials and drug-delivery systems has had a significant impact on our ability to treat several diseases. A new study was performed on niosomal formulations obtained from a mixture of commercial surfactants (Tween 80 and Span 80) to be applied topically for the release of Capsaicin. Capsaicin is the pungent principle of red pepper and it has a variety of pharmacological actions on the cardiovascular, respiratory and nervous systems. Niosomal carriers were prepared using a particular ratio between surfactants, to obtain systems with a specific HLB (10,12,14) and characterized in terms of dimension, morphology and their drug entrapment efficiency. Niosomes were compared to microemulsions prepared from the same surfactants in the same ratio, to evaluate their possible use in transdermal drug delivery. As regards the in vitro percutaneous permeation of Capsaicin from both microemulsions and niosomal formulations, it was carried out using diffusion Franz cells. The results indicate that niosomes could better promote the transdermal delivery of Capsaicin, with respect to microemulsions, even if both carriers could be an effective vehicle for topical delivery of this drug.

Chemical composition and bioactivity of Citrus medica L. cv. Diamante essential oil obtained by hydrodistillation, cold-pressing and supercritical carbon dioxide extraction.

The chemical composition of the essential oil of Citrus medica L. cv. Diamante peel obtained by hydrodistillation, cold-pressing and supercritical carbon dioxide extraction techniques was determined by GC/MS analysis. Forty-six components were fully characterised. Limonene and γ-terpinene were the major components of the oils obtained by hydrodistillation (HD) and cold-pressing (CP), while citropten was the major constituent in the oil obtained by supercritical carbon dioxide extraction (SFE). Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities were evaluated. The essential oil obtained by hydrodistillation exerted the highest inhibitory activity against BChE (IC50 value of 154.6 µg mL⁻¹) and AChE (IC50 value of 171.3 µg mL⁻¹. Interestingly, the oil obtained by cold-pressing exhibited a selective inhibitory activity against AChE. The essential oils have also been evaluated for the inhibition of NO production in LPS induced RAW 264.7 macrophages. The oil obtained by hydrodistillation exerted a significant inhibition of NO production with an IC50 value of 17 µg mL⁻¹ (IC50 of positive control 53 µg mL⁻¹).

Phytochemical profile, antioxidant, anti-inflammatory and hypoglycemic potential of hydroalcoholic extracts from Citrus medica L. cv Diamante flowers, leaves and fruits at two maturity stages.

Since the past decade consumption of certain foods has been reported to have a positive effect on health. The object of the study was to determine for the first time the chemical composition and the antioxidant, anti-inflammatory and hypoglycemic potential of Citrus medica L. cv Diamante flowers, leaves and fruits (endocarp and mesocarp) at two maturity stages. Flowers and leaves were characterized by the highest total phenols and flavonoids content. A declining trend was observed during maturity of fruits for both phenols and flavonoids. The antioxidant activity evaluated by the ß-carotene bleaching test showed a strong activity for flowers and endocarp of mature fruits with IC50 values of 2.8 µg/mL and 3.5 µg/mL, respectively, after 30 min of incubation. Interestingly, the mature fruits endocarp (IC50 value of 426.0 µg/mL) could inhibit α-amylase with an IC50 value 2-fold higher than immature fruits. None of the tested extracts affected the proliferation of human skin fibroblasts 142BR. The obtained results suggest a potential use of C. medica L. cv Diamante as new valuable Citrus species with functional properties for food or nutraceutical product on the basis of high content of phytochemicals.

Protective effect of Pimpinella anisoides ethanolic extract and its constituents on oxidative damage and its inhibition of nitric oxide in lipopolysaccharide-stimulated RAW 264.7 macrophages.

The present study shows for the first time the chemical profile and the in vitro properties (antioxidant and inhibition of nitric oxide [NO] production) of the aromatic plant Pimpinella anisoides V Brig. (Family Apiaceae). The ethanolic extract of the fruits is characterized by 23 major components. Fourteen monoterpenes, two sesquiterpenes, one fatty acid, five methyl esters and one aldehyde were identified. Among them the most abundant components were the monoterpenes trans-anethole (54.5%), limonene (13.5%), and sabinene (4.4%). The extract showed significant antioxidant activity (50% inhibitory concentration [IC(50)], 3.02 mg/mL) using the 2,2-diphenyl-1-picrylhydrazyl test. The test for inhibition of NO production was performed using the murine monocytic macrophage cell line RAW 264.7. The ethanolic extract had significant activity with an IC(50) value of 72.7 microg/mL, and this might indicate that it would have an anti-inflammatory effect in vivo. Among the pure compounds that most effectively inhibited lipopolysaccharide-induced NO production were the most abundant constituents, trans-anethole and limonene, with IC(50) values of 102.7 microg/mL and 70.1 microg/mL, respectively. The cytotoxic effect of P. anisoides extract and pure compounds in the presence of lipopolysaccharide (1 microg/mL) was evaluated but found to be negligible.