Synergistic activity of pomegranate rind extract and Zn (II) against Candida albicans under planktonic and biofilm conditions, and a mechanistic insight based upon intracellular ROS induction.

Candida albicans (C. albicans) is an opportunistic pathogen, which causes superficial infection and can lead to mortal systemic infections, especially in immunocompromised patients. The incidence of C. albicans infections is increasing and there are a limited number of antifungal drugs used in treatment. Therefore, there is an urgent need for new and alternative antifungal drugs. Pomegranate rind extract (PRE) is known for its broad-spectrum antimicrobial activities, including against C. albicans and recently, PRE and Zn (II) have been shown to induce synergistic antimicrobial activity against various microbes. In this study, the inhibitory activities of PRE, Zn (II) and PRE in combination with Zn (II) were evaluated against C. albicans. Antifungal activities of PRE and Zn (II) were evaluated using conventional microdilution methods and the interaction between these compounds was assessed by in vitro checkerboard and time kill assays in planktonic cultures. The anti-biofilm activities of PRE, Zn (II) and PRE in combination with Zn (II) were assessed using confocal laser scanning microscopy, with quantitative analysis of biofilm biomass and mean thickness analysed using COMSTAT2 analysis. In addition, antimicrobial interactions between PRE and Zn (II) were assayed in terms reactive oxygen species (ROS) production by C. albicans. PRE and Zn (II) showed a potent antifungal activity against C. albicans, with MIC values of 4 mg/mL and 1.8 mg/mL, respectively. PRE and Zn (II) in combination exerted a synergistic antifungal effect, as confirmed by the checkerboard and time kill assays. PRE, Zn (II) and PRE and Zn (II) in combination gave rise to significant reductions in biofilm biomass, although only PRE caused a significant reduction in mean biofilm thickness. The PRE and Zn (II) in combination caused the highest levels of ROS production by C. albicans, in both planktonic and biofilm forms. The induction of excess ROS accumulation in C. albicans may help explain the synergistic activity of PRE and Zn (II) in combination against C. albicans in both planktonic and biofilm forms. Moreover, the data support the potential of the PRE and Zn (II) combination as a novel potential anti-Candida therapeutic system.

A Time-Kill Assay Study on the Synergistic Bactericidal Activity of Pomegranate Rind Extract and Zn (II) against Methicillin-Resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa.

There is a need for new antimicrobial systems due to increased global resistance to current antimicrobials. Pomegranate rind extract (PRE) and Zn (II) ions both possess a level of antimicrobial activity and work has previously shown that PRE/Zn (II) in combination possesses synergistic activity against Herpes simplex virus and Micrococcus luteus. Here, we determined whether such synergistic activity extended to other, more pathogenic, bacteria. Reference strains of methicillin-resistant Staphylococcus aureus (MRSA), Staphylococcus epidermidis, Escherichia coli, and Pseudomonas aeruginosa were cultured and subjected to challenge by PRE, Zn (II), or PRE + Zn (II), in time-kill assays. Data were obtained independently by two researchers using different PRE preparations. Statistically significant synergistic activity for PRE + Zn (II) was shown for all four bacterial strains tested compared to untreated controls, although the extent of efficacy and timescales varied. Zn (II) exerted activity and at 1 h, it was not possible to distinguish with PRE + Zn (II) combination treatment in all cases. PRE alone showed low activity against all four bacteria. Reproducible synergistic bactericidal activity involving PRE and Zn (II) has been confirmed. Potential mechanisms are discussed. The development of a therapeutic system that possesses demonstrable antimicrobial activity is supported which lends itself particularly to topical delivery applications, for example MRSA infections.

Anti-Proliferative, Cytotoxic and Antioxidant Properties of the Methanolic Extracts of Five Saudi Arabian Flora with Folkloric Medicinal Use: Aizoon canariense, Citrullus colocynthis, Maerua crassifolia, Rhazya stricta and Tribulus macropterus.

Saudi Arabian flora have a history of use as folklore remedies, although such properties have yet to be explored rigorously, and the safety of such remedies should be assessed. This study determined the anti-proliferative, cytotoxic, and antioxidant properties of extracts of the following five plants indigenous to Saudi Arabia: Aizoon canariense, Citrullus colocynthis, Maerua crassifolia, Rhazya stricta, and Tribulus macropterus. The aerial parts of the five plants were collected from various locations of the western and northern regions of Saudi Arabia and used to prepare methanolic extracts. Three approaches were used to determine the proliferation and cytotoxicity effects using HaCaT cells: MTT, FACS, and confocal microscopy. Meanwhile, two approaches were used to study the antioxidant potential: DPPH (acellular) and RosGlo (cellular, using HaCaT cells). C. colocynthis possessed anti-proliferative activity against HaCaT cells, showing a significant decrease in cell proliferation from 24 h onwards, while R. stricta showed significant inhibition of cell growth at 120 and 168 h. The IC50 values were determined for both plant extracts for C. colocynthis, with 17.32 and 16.91 µg/mL after five and seven days of treatment, respectively, and for R. stricta, with 175 and 105.3 µg/mL after five and seven days of treatment. R. stricta and M. crassifolia exhibited the highest capacities for scavenging the DPPH radical with IC50 values of 335 and 448 µg/mL, respectively. The subsequent ROS-Glo H2O2 assay confirmed these findings. The R. stricta and M. crassifolia extracts showed potent antioxidant activity in both acellular and cellular models. The C. colocynthis extract also demonstrated significant anti-proliferation and cytotoxic activity, as did the R. stricta extract. These properties support their usage in folk medicine and also indicate a further potential for development for holistic medicinal use or as sources of new active compounds.

Synergistic In Vitro Antimicrobial Activity of Pomegranate Rind Extract and Zinc (II) against Micrococcus luteus under Planktonic and Biofilm Conditions.

Infectious diseases caused by microbial biofilms are a major clinical problem, and new antimicrobial agents that can inhibit biofilm formation and eradicate pre-formed biofilms are urgently needed. Pomegranate extracts are a well-established folkloric medicine and have been used in the treatment of infectious diseases since ancient times, whilst the addition of metal ions, including zinc (II), has enhanced the antimicrobial activity of pomegranate. Micrococcus luteus is generally a non-pathogenic skin commensal bacterium, although it can act as an opportunistic pathogen and cause serious infections, particularly involving catheterization and comorbidities. The aims of this study were to evaluate the holistic activity of pomegranate rind extract (PRE), Zn (II), and PRE/Zn (II) individually and in combination against M. luteus under both planktonic and biofilm conditions. Antimicrobial activity was detected in vitro using the broth dilution method, and synergistic activity was determined using checkerboard and time-kill assays. Effects on biofilm formation and eradication were determined by crystal violet and BacLightTM Live/Dead staining. PRE and Zn (II) exerted antimicrobial activity against M. luteus under both planktonic and biofilm conditions. After 4 h, potent synergistic bactericidal activity was also found when PRE and Zn (II) were co-administered under planktonic conditions (log reductions: PRE 1.83 ± 0.24, Zn (II) 3.4 ± 0.08, and PRE/Zn (II) 6.88 ± 1.02; p < 0.0001). In addition, greater heterogeneity was induced in the structure of M. luteus biofilm using the PRE/Zn (II) combination compared to when PRE and Zn (II) were applied individually. The activity of PRE and the PRE/Zn (II) combination could offer a novel antimicrobial therapy for the treatment of disease-associated infections caused by M. luteus and potentially other bacteria.

Evaluation of the In Vitro Oral Wound Healing Effects of Pomegranate (Punica granatum) Rind Extract and Punicalagin, in Combination with Zn (II).

Pomegranate (Punica granatum) is a well-established folklore medicine, demonstrating benefits in treating numerous conditions partly due to its antimicrobial and anti-inflammatory properties. Such desirable medicinal capabilities are attributed to a high hydrolysable tannin content, especially punicalagin. However, few studies have evaluated the abilities of pomegranate to promote oral healing, during situations such as periodontal disease or trauma. Therefore, this study evaluated the antioxidant and in vitro gingival wound healing effects of pomegranate rind extract (PRE) and punicalagin, alone and in combination with Zn (II). In vitro antioxidant activities were studied using DPPH and ABTS assays, with total PRE phenolic content measured by Folin-Ciocalteu assay. PRE, punicalagin and Zn (II) combination effects on human gingival fibroblast viability/proliferation and migration were investigated by MTT assay and scratch wounds, respectively. Punicalagin demonstrated superior antioxidant capacities to PRE, although Zn (II) exerted no additional influences. PRE, punicalagin and Zn (II) reduced gingival fibroblast viability and migration at high concentrations, but retained viability at lower concentrations without Zn (II). Fibroblast speed and distance travelled during migration were also enhanced by punicalagin with Zn (II) at low concentrations. Therefore, punicalagin in combination with Zn (II) may promote certain anti-inflammatory and fibroblast responses to aid oral healing.

Mucoadhesive thin films for the simultaneous delivery of microbicide and anti-inflammatory drugs in the treatment of periodontal diseases.

There is an unmet clinical need for new products to address the high percentage of the populous who present with periodontal diseases. Drug dose retention at the point of application would facilitate sustained release and more efficacious treatments. The aim of this study was to evaluate mucoadhesive polymeric thin films for simultaneous in situ delivery chlorhexidine and anti-inflammatory and analgesic drugs. Mucoadhesive thin films were prepared using a polymer mixture containing chlorhexidine (25 mg) ± diclofenac sodium (10 and 50 mg), and lidocaine hydrochloride (10 mg) or betamethasone dipropionate (10 and 50 mg). The films were assessed for in vitro drug release and localised tissue delivery, followed by determination of modulated prostaglandin E2 (PGE2) levels in ex vivo tissue and cytotoxicity using a HaCaT keratinocyte cell line. Antibacterial activity of the chlorhexidine/diclofenac film was determined against planktonic and biofilm bacteria associated with periodontal disease and dental plaque. Chlorhexidine release was consistently low (up to 10% of initial loading) from all films, whereas the release of diclofenac, betamethasone and lidocaine exceeded 50% within 30 min. The 50 mg betamethasone film released up to 4-fold more than the 10 mg film. Statistically significant reduction of PGE2 was observed in ex vivo porcine gingival tissue for films containing chlorhexidine with or without diclofenac, and betamethasone. No cytotoxicity was observed for any film, apart from 50 mg betamethasone at 24 h. Films loaded with chlorhexidine and diclofenac were inhibitory against relevant test bacteria. Between 3 and 6 log10 reductions in bacterial cell recovery was observed after biofilm exposure to the chlorhexidine films irrespective of the presence of the anti-inflammatory or anaesthetic. This work demonstrated that thin film formulations have the potential to simultaneously counter key causative factors in periodontal diseases, namely associated bacteria biofilm and chronic local inflammation.

Isolation of punicalagin from Punica granatum rind extract using mass-directed semi-preparative ESI-AP single quadrupole LC-MS.

We are living in a era of alarming increases in microbial resistance to currently available antibiotics, and there is a growing need for new pharmaceutical products to treat infectious diseases. The pomegranate is an edible fruit that has virucidal and antimicrobial activities which is primarily attributable to the high concentration of hydrolysable tannins. Punicalagin, a high molecular weight tannin (1084.7), accounts for approximately 70% of the total and is concentrated in the fruit exocarp (rind). It is the focus of much research, although it is prohibitively expensive to purchase which presents an obstacle to further exploitation and development. Here we describe a method for the isolation of punicalagin from pomegranate rind extract and total pomegranate tannins using an Agilent preparative mass-directed LC-MS single quadrupole ESI-API system, where the ionization was set as negative and the mass signal acquired in Single Ion Monitoring. Thanks to the automatic fraction collector, the method can be used in automatic mode and is capable of producing punicalagin with >95% purity.

Potentiated virucidal activity of pomegranate rind extract (PRE) and punicalagin against Herpes simplex virus (HSV) when co-administered with zinc (II) ions, and antiviral activity of PRE against HSV and aciclovir-resistant HSV.

BACKGROUND: There is a clinical need for new therapeutic products against Herpes simplex virus (HSV). The pomegranate, fruit of the tree Punica granatum L, has since ancient times been linked to activity against infection. This work probed the activity of pomegranate rind extract (PRE) and co-administered zinc (II) ions. MATERIALS AND METHODS: PRE was used in conjunction with zinc (II) salts to challenge HSV-1 and aciclovir-resistant HSV in terms of virucidal plaque assay reduction and antiviral activities in epithelial Vero host cells. Cytotoxicity was determined by the MTS assay using a commercial kit. RESULTS: Zinc sulphate, zinc citrate, zinc stearate and zinc gluconate demonstrated similar potentiated virucidal activity with PRE against HSV-1 by up to 4-fold. A generally parabolic relationship was observed when HSV-1 was challenged with PRE and varying concentrations of ZnSO4, with a maximum potentiation factor of 5.5. Punicalagin had 8-fold greater virucidal activity than an equivalent mass of PRE. However, antiviral data showed that punicalagin had significantly lower antiviral activity compared to the activity of PRE (EC50 = 0.56 µg mL-1) a value comparable to aciclovir (EC50 = 0.18 µg mL-1); however, PRE also demonstrated potency against aciclovir-resistant HSV (EC50 = 0.02 µg mL-1), whereas aciclovir showed no activity. Antiviral action of PRE was not influenced by ZnSO4. No cytotoxicity was detected with any test solution. CONCLUSIONS: The potentiated virucidal activity of PRE by coadministered zinc (II) has potential as a multi-action novel topical therapeutic agent against HSV infections, such as coldsores.

Anti-inflammatory activity of Punica granatum L. (Pomegranate) rind extracts applied topically to ex vivo skin.

Coadministered pomegranate rind extract (PRE) and zinc (II) produces a potent virucidal activity against Herpes simplex virus (HSV); however, HSV infections are also associated with localised inflammation and pain. Here, the objective was to determine the anti-inflammatory activity and relative depth penetration of PRE, total pomegranate tannins (TPT) and zinc (II) in skin, ex vivo. PRE, TPT and ZnSO4 were dosed onto freshly excised ex vivo porcine skin mounted in Franz diffusion cells and analysed for COX-2, as a marker for modulation of the arachidonic acid inflammation pathway, by Western blotting and immunohistochemistry. Tape stripping was carried out to construct relative depth profiles. Topical application of PRE to ex vivo skin downregulated expression of COX-2, which was significant after just 6h, and maintained for up to 24h. This was achieved with intact stratum corneum, proving that punicalagin penetrated skin, further supported by the depth profiling data. When PRE and ZnSO4 were applied together, statistically equal downregulation of COX-2 was observed when compared to the application of PRE alone; no effect followed the application of ZnSO4 alone. TPT downregulated COX-2 less than PRE, indicating that tannins alone may not be entirely responsible for the anti-inflammatory activity of PRE. Punicalagin was found throughout the skin, in particular the lower regions, indicating appendageal delivery as a significant route to the viable epidermis. Topical application of TPT and PRE had significant anti-inflammatory effects in ex vivo skin, confirming that PRE penetrates the skin and modulates COX-2 regulation in the viable epidermis. Pomegranates have potential as a novel approach in ameliorating the inflammation and pain associated with a range of skin conditions, including cold sores and herpetic stromal keratitis.

A novel diffusion cell model for the in vitro assessment of transcutaneous breast cancer therapeutics: effect of permeants on MCF-7 cells cultured within the receptor compartment.

A novel model is described for investigating the potential efficacy of topically delivered anti-breast cancer agents. Using all-glass Franz diffusion cells, the permeation of 4-hydroxytamoxifen, two EGFR inhibitors (PD98059 and LY294002) and eicosapentaenoic acid (EPA) were determined from a fish oil vehicle across Cyclopore track etched membrane (CTEM) alone, full-thickness porcine ear skin alone and CTEM plus full-thickness porcine ear skin. Finally, the effect of the simultaneous permeation of these compounds was determined on the breast cancer cell line, MCF-7, cultured directly into the diffusion cell receptor compartments. The CTEM was found to be not rate limiting, and all compounds permeated the skin, with a large excess of EPA. The applied combined dose reduced the growth of MCF-7 cells by 66% after 7days. The following conclusions were obtained: (1) MCF-7 breast cancer cells can be successfully cultured within glass Franz diffusion cells. (2) A composite diffusion cell/cell culture model can indicate the potential efficacy of topically delivered anti-breast cancer therapeutic agents. (3) The levels of LY294002, PD98059, 4-hydroxytamoxifen and EPA delivered across full-thickness skin have a major inhibitory effect on the growth of MCF-7 breast cancer cells.

A novel ex vivo skin model for the assessment of the potential transcutaneous anti-inflammatory effect of topically applied Harpagophytum procumbens extract.

Using ex vivo skin as a model, this work tested the hypothesis that the major pharmacologically active components of topically applied Harpagophytum procumbens (H. procumbens) can elicit anti-inflammatory responses in deeper tissues post-transcutaneous delivery. Using Franz-type diffusion cells, ethanol extract of powdered H. procumbens tuber was dosed onto freshly excised porcine skin. After 24 h the receptor phase was recovered, analysed for the major glycosides of DC, then used directly to dose further freshly excised skin membranes. After 6h the skin was recovered and probed for the expression of the three major enzymes involved in the inflammatory factors: cyclooxygenase (COX-2) and its product prostaglandin E2 (PGE-2), lipoxygenase (5-LOX), and inducible nitric oxide (iNOS), using immunocytochemistry and Western blotting analyses. It was found that the receptor phase at 24 h contained (0.8, 25, 1.8, 3 x 10(-3)) micromol mL(-1) of harpagoside, harpagide, verbascoside, 8-O-p-coumaroyl-harpagide, respectively. When applied to skin, this solution effectively inhibited the expression of COX-2 and its product PGE-2. However, it did not have a significant effect on either 5-LOX or iNOS compared to control samples (PBS only). These data support the hypothesis that the transcutaneous delivery of H. procumbens can treat inflammation in deeper tissues such as in arthritis. Moreover, a novel ex vivo model has been described for assessing the potential anti-inflammatory activity of permeants delivered to deeper subcutaneous regions.

Dermal and transcutaneous delivery of the major glycoside constituents of Harpagophytum procumbens (Devil's Claw) in vitro.

The potential of the administration of Harpagophytum procumbens extract via the topical route has not been studied previously. In the current work, the dermal and transcutaneous delivery of the major pharmacologically active constituents present in H. procumbens tuber extract were determined across porcine ear skin from four vehicles: de-ionised water, 30 % ethanol in water (v/v), PEG 400, 50 : 50 PEG 400 in 30 % EtOH (v/v). Permeation profiles were obtained under infinite conditions and tape stripping was performed at 24 h. The permeation of the compounds varied according to their physicochemical properties as well as the nature of the vehicle. The highest permeation was found from the ethanol/water saturated solutions and the lowest MW harpagide was obtained at significantly higher concentrations in the receptor phase compared to the rest of the compounds, with the permeability coefficient being inversely dependent on dielectric constant of the vehicle. Depth profiling revealed higher penetration of all compounds from ethanol/water; in addition, significantly higher amounts of the pro-inflammatory harpagide were present in the strips and the remaining epidermis compared to other compounds. This suggests that ethanol is not a suitable vehicle as it leads to more harpagide penetration, potentially counteracting the anti-inflammatory activity of the other compounds. The development of new systems for local cutaneous inflammation (e. g., psoriasis, eczema) and subcutaneous inflammation (e. g., arthritis) is supported.

Topical delivery of retinyl ascorbate. 3. Influence of follicle sealing and skin stretching.

This influence of skin stretching and hair follicle sealing on the delivery of retinyl ascorbate (RA-AsA) to the epidermis was probed in vitro. Porcine ear skin was subjected to stretching by 2 and 4 mm (3.3 and 6.7%, respectively); the hair follicles of other skin sections were located and painstakingly sealed using adhesive. After mounting in Franz cells the skin was dosed with 100 microl of 2.5 mM RA-AsA in methanol/PBS with water as receptor phase. After 24 h the diffused areas were subjected to tape stripping, and the amount of RA-AsA was determined in 5 groups of 9 strips. Statistical analysis of the resulting depth profiles showed that there was no statistical difference between unstretched skin and the skin that had the follicles sealed across the 5 depth bands. Between 0 and 2 mm stretch there were generally significant differences; between 0 and 4 mm p < 0.001 was obtained at each depth. The data from this limited exercise suggest that in native skin the follicular route does not contribute to dermal absorption, but when disturbed (as when stretched) follicular delivery can substantially increase drug delivery into the skin by up to approximately 20-40%. Skin stretching becomes difficult beyond about 7%.

In vitro transdermal delivery of caffeine, theobromine, theophylline and catechin from extract of Guarana, Paullinia Cupana.

Extracts of guarana (Paullinia cupana) feature as putatively stimulating ingredients in a number of foods, drinks and dietary/herbal supplements. The objective of this work was to investigate in vitro the transdermal delivery of the major pharmacologically active compounds contained in guarana extract. Saturated solutions of guarana were prepared in polyethylene glycol 400 (PEG400), propylene glycol (PG) and H(2)O at 32 degrees C. Guarana extract was also formulated in Duro-tak 2287 transdermal adhesive in a range of concentrations and the diffusional release was determined in addition to adhesive properties. Transdermal delivery across full thickness pig ear skin was investigated in vitro using Franz-type diffusion cells, with reverse-phase HPLC being used for the quantification of the permeation of theobromine (TB), theophylline (TP), (+)-catechin (C) and caffeine (CF). Based upon a combination of release and adhesive property data a patch containing 5.55 mg guarana extract cm(-2) was deemed optimal. The general trend for the delivery of the 4 analytes was: water >5.55 mg cm(-2) patch approximately PG>PEG400. For CF the greatest steady state flux was obtained from the water vehicle: 19 microg cm(-2)h(-1), with approximately 420 microg cm(-2) permeating after 24h. This was some 6x times more than from the drug-in-adhesive patch and 10x greater than PG, a well-known penetration enhancer, and 50x that of the 'regular' excipient PEG400. A water vehicle also provided the greatest delivery of TB (0.45 microg cm(-2) h(-1)), TP (0.022 microg cm(-2) h(-1)), and C (0.10 microg cm(-2) h(-1)). An inverse relationship was noted between lipophilicity and k(p) in each vehicle. The simultaneous transdermal delivery of the major actives of guarana was established, with permeation rates being highly concentration and vehicle dependent.

Preferential pi-pi complexation between tamoxifen and borage oil/gamma linolenic acid: transcutaneous delivery and NMR spectral modulation.

The effect of different proportions of borage oil on the in vitro transcutaneous delivery of tamoxifen were studied, with the aim of developing a gel capable of the simultaneous delivery of tamoxifen and gamma linolenic acid across (breast) skin. Supplementary work probed 1H NMR spectral data for tamoxifen in the presence of different proportions of polyunsaturated or unsaturated fatty acids. Typical, non-aqueous gels were modified to contain 1% tamoxifen and three levels of borage oil ( approximately 25% gamma linolenic acid) and the transcutaneous delivery of both tamoxifen and GLA across full thickness skin determined in vitro. Both tamoxifen and gamma linolenic acid permeated the skin with the ratio of moles being consistent at approximately 4:1. This was irrespective of time, amount of borage oil contained in the formulation (above a minimum) and the presence of other (unsaturated) excipients: mineral oil, Miglyiol 810N, white soft paraffin, PEG400 and Cabosil M5. Dose-dependent downfield shifts of tamoxifen aromatic protons were observed in the presence of borage oil and linolenic acid (gamma and alpha), but not saturated triacyl glycerol. The permeation data suggested vehicular complexation between tamoxifen and polyunsaturated constituents of borage oil and that such complexes permeated the skin intact. The 1H NMR data supported the hypothesis that such complexation was a consequence of preferential pi-pi orbital interactions between the phenyl groups of tamoxifen and the multiple double bonds of GLA. The mechanism for the permeation of intact complexes across skin remains to be elucidated.

In-vitro transcutaneous delivery of tamoxifen and gamma-linolenic acid from borage oil containing ethanol and 1,8-cineole.

The objective of this study was to examine the effects of ethanol and 1,8-cineole on the transcutaneous delivery of tamoxifen and gamma-linolenic acid (GLA) as a two-pronged anti-breast cancer therapy. Formulations containing tamoxifen and varying concentrations of borage oil (approximately 25% GLA), 1,8-cineole and ethanol were prepared and the simultaneous permeation of tamoxifen and GLA determined across full-thickness pig skin using Franz-type diffusion cells over 48 h. Analysis of tamoxifen and GLA (as methyl ester) were by reverse-phase HPLC. The highest flux of tamoxifen of 488.2 +/- 191 x 10(-3) microg cm(-2) h(-1) was observed with a formulation containing 20% 1,8-cineole and 20% ethanol. The same formulation also provided the greatest flux of GLA, 830.6 x 10(-3) microg cm(-2 )h(-1). The findings from this work demonstrate the ability of 1,8-cineole and ethanol to enhance the in-vitro permeation of tamoxifen and GLA across the skin and support the plausibility of simultaneously delivering tamoxifen and GLA transcutaneously as a two-pronged anti-breast cancer system.

In vitro transdermal delivery of the major catechins and caffeine from extract of Camellia sinensis.

The aim of this study was to investigate the feasibility of the transdermal delivery of catechins and caffeine from green tea extract. Drug-in-adhesive patches containing 1.35, 1.03, 0.68, and 0.32 mg cm(-2) green tea extract were formulated and the dissolution of (-)-epigallocatechin gallate (EGCg), (-)-epigallocatechin (EGC) and (-)-epicatechin (EC) from these was determined. Transdermal delivery was determined across full thickness pig ear skin from saturated solutions of green tea extract in pH 5.5 citrate-phosphate buffer, polyethylene glycol 400 and a 50:50 mixture of the citrate phosphate buffer and polyethylene glycol in addition to patches containing 1.35 mg cm(-2) green tea extract. Dissolution experiments indicated first order release which was dose dependent in respect of the loading level, although the amounts permeated were not always proportional to the amounts in the formulation. The highest percentage permeation of EGCg was found to be from the patch formulation. EGCg, EGC and EC were all successfully delivered transdermally from saturated solutions and adhesive patches containing green tea extract in this study. There was some evidence for the dermal metabolism of EGCg, but after 24 h 0.1% permeated from the patches containing 1.35 mg cm(-2) green tea extract. This was equivalent to the percentage absorbed after intragastric administration of green tea extract in rats. In addition, the concentration of EGCg in the Franz cell receptor chamber after 24 h permeation from the 0.9 cm diameter patch containing 1.35 mg cm(-2) was within the range of Cmax plasma levels achieved after oral dosing of 2.2-4.2 gm(-2) green tea extract. Caffeine was also delivered at concentrations above those previously reported.

Targeted dermal delivery of highly potent anti-varicella zoster virus nucleoside analogues from saturated solutions and ethanolic oil-in-water creams.

Varicella zoster virus (VZV) is responsible for causing chickenpox and shingles infections, the latter of which can lead to long-term post-herpetic neuralgia (PHN), the most common complication of VZV infections. A class of anti-VZV nucleoside analogues has been synthesised that shows up to 30,000 times the potency of aciclovir in vitro. The relatively high lipophilicities exhibited by the compounds led them to be selected for dermal delivery. The aim was to assess the relative penetration and permeation of the compounds into and through the skin, ideally targeting the region of skin in which the reactivated virus replicates. By targeting the skin it should be possible to reduce the viral load that causes damage to the nerves, thereby limiting zoster-associated pain, in particular PHN. Three compounds, as saturated solutions or as ethanol-based creams, were applied to full-thickness pig ear skin in Franz-type diffusion cells. An ethanolic and water receptor phases were compared. Samples of the receptor phase were taken at specific intervals, followed by tape stripping and separation of the remaining membrane at the end of the experiment. Analysis of the samples showed that all three compounds penetrated into the ethanolic receptor phase to a considerable degree, while only the least lipophilic compound entered the water receptor phase. The effects of the organic solvent in the receptor phase were visible in both the penetration and permeation of the compounds. All three compounds were distributed throughout the membrane in a manner that indicates that the site of viral replication in the skin is reached.