Development and evaluation of topical films containing phytoestrogenic diaryheptanoids from Curcuma comosa extract

Formulation and In Vitro Evaluation of Mucoadhesive Sustained Release Gels of Phytoestrogen Diarylheptanoids from Curcuma comosa for Vaginal Delivery

Diarylheptanoids (DAs) characterized by a 1,7-diphenylheptane structural skeleton are considered a novel class of phytoestrogens. The DAs available in Curcuma comosa Roxb. (C. comosa) extract demonstrated significant estrogenic activities both in vitro and in vivo. This study aimed to develop and comprehensively evaluate a mucoadhesive vaginal gel for the sustained release of DAs. Different mucoadhesive polymers as gelling agents were investigated. C. comosa ethanolic crude extract was used as a source of DAs. All C. comosa gels were light brown homogeneous with pH within 4.4-4.6. Their flow behaviors were pseudoplastic with a flow behavior index of 0.18-0.38. The viscosity at a low shear rate varied from 6.2 to 335.4 Pa·s. Their mechanical and extrudability properties were associated well with rheological properties. Polycarbophil (PCP):hydroxypropyl methylcellulose (HPMC) blends had a higher mucoadhesiveness to porcine vaginal mucosa than those of PCP-based or HPMC-based gels. All C. comosa gels exhibited a sustained, zero-order DA release pattern over 72 h. Korsmeyer and Peppas equation fitting indicated a non-Fickian, case II transport release mechanism. C. comosa gels had good physical and chemical stability under low-temperature storage for up to 12 months. PCP:HPMC-based mucoadhesive gels could be a proper delivery system for vaginal administration of DAs.

Development and Characterisation of a Topical Methyl Salicylate Patch: Effect of Solvents on Adhesion and Skin Permeation

The advent of skin patch formulation design and technology has enabled the commercialisation of methyl salicylate (MS) as a topical patch. However, the most fundamental aspect of skin permeation is unknown at present. The study aims to investigate the effect of solvent choice on the skin permeation of MS in a neat solvent system and patch formulation with an emphasis on patch adhesion. MS in six selected solvents (propylene glycol (PG), Transcutol^®, isopropyl myristate, Labrasol^®, Plurol^® oleique CC 497 and Maisine^® CC) was characterised and in vitro permeation studies were also performed. An ATR-FTIR analysis on solvent-treated skin was conudcted. Patch formulation was prepared and characterised for adhesion, in vitro drug release and skin permeation studies. The highest MS permeation was found in neat PG over 24 h (~90 μg/cm²) due to its strong skin protein conformation effect. Transcutol^® and isopropyl myristate showed better skin deposition and formulation retention, respectively. Nevertheless, PG enhanced the patch adhesion despite having a lower cumulative amount of MS permeated (~80 μg/cm²) as compared with Transcutol^® and Maisine^® (~110-150 μg/cm²). These two solvents, however, demonstrated better skin deposition and formulation retention but a lower patch adhesion. The unpredictable influence of the solvent on patch adhesion highlights the importance of the trade-off between patch adhesion and skin permeation during formulation design.

Formulation Development and Pharmaceutical Evaluation of Lysiphyllum strychnifolium Topical Patches for Their Anti-inflammatory Potential

Topical drug delivery systems are interesting and popular dosage forms for formulation development. Thai herbs are used in alternative medicine to treat patients suffering from severe illnesses. They have significant economic and cultural value in Thailand. This work prepared Thai herbal topical patches of Lysiphyllum strychnifolium stem extracts using pectin and Eudragit^® NM 30D, and glycerin as a plasticizer. Astilbin was selected as a chemical marker in L. strychnifolium stem extracts. The L. strychnifolium stem extracts showed a statistically significant decrease in nitrate accumulation. The various properties of Thai herbal topical patches were not significantly different from blank patches. However, the trends of the properties depended on the amount of Eudragit^® NM 30D. All ingredients were homogeneously mixed in Thai herbal topical patches and showed a smooth and compact film. The astilbin content was found in a range of 52.72-63.36 μg/cm². The in vitro release of astilbin depended on the amount of Eudragit^® NM 30D. The kinetics of astilbin release were fitted to the Korsmeyer-Peppas model. The astilbin showed low permeation; thus, polyethylene glycol 400 was used as a permeation enhancer. Polyethylene glycol 400 could increase the permeation rates of astilbin and the cumulative amount of astilbin in pig skin. This would be suitable for preparing the Thai herbal topical patches and could be developed for pharmaceutical and herbal products.

Modification of release and penetration behavior of water-soluble active ingredient from ball-milled glutinous starch matrix via carboxymethylcellulose blending

This present work describes the possible advantages of carboxymethylcellulose (CMC) blending with ball-milled glutinous starch (BMGS) on the modification of release and penetration of model water-soluble active ingredient, lidocaine hydrochloride, from the blended matrix. The 20-67% CMC mass containing CMC-BMGS matrices were fabricated by casting the aqueous dispersion of CMC-BMGS onto the tray and oven-dried. BMGS and CMC were compatible as revealed by SEM and ATR-FTIR. Irrespective of the CMC mass, all CMC-BMGS matrices showed comparable matrix mass, thickness, moisture content, moisture absorption as well as mechanical and mucoadhesive properties. The surface pH of CMC-BMGS tended to increase with the CMC mass. Depends on CMC mass, matrix properties, release, and penetration rates were modulated significantly. CMC had shown a substantial role in the swelling and erosion behaviors of BMGS films, and thus modulated the release and penetration significantly. The release and penetration mechanisms of active ingredient from the CMC-BMGS matrices were Fickian diffusion-controlled, with rates of release and penetration ranging from 2.05 ± 0.21 to 7.55 ± 1.08%/min^½, and from 3.48 ± 0.28 to 8.04 ± 0.64 μg/cm²/min^½, respectively. The capability of CMC-BMGS matrices as mucoadhesive delivery systems to provide sustained delivery of water-soluble active ingredients was disclosed.

Recent advances in the anti-aging effects of phytoestrogens on collagen, water content, and oxidative stress

Skin undergoes degenerative changes as it ages, which include the loss of elasticity, reductions in the epidermal thickness and collagen content, elastic fiber degeneration, and increased wrinkling and dryness. Skin aging can be significantly delayed by the administration of estrogen. Estrogen deficiency following menopause results in atrophic skin changes and the acceleration of skin aging. Estrogen administration has positive effects on human skin by delaying or preventing skin aging manifestations, but the use of estrogen replacement is a risk factor for breast and uterine cancer. Phytoestrogens are a large family of plant‐derived molecules possessing various degrees of estrogen‐like activity; they exhibit agonist or antagonist estrogenic properties depending on the tissue. These molecules could be ideal candidates to combat skin aging and other detrimental effects of hypoestrogenism. In this paper, we review the effects of phytoestrogens on human skin and the mechanisms by which phytoestrogens can alleviate the changes due to aging.