Evaluation of octyl p-methoxycinnamate included in liposomes and cyclodextrins in anti-solar preparations: preparations, characterizations and in vitro penetration studies

Comparative Study of Liposomal and Ethosomal Formulations of Curcuma heyneana Rhizome Extract in a Transdermal Delivery System

AIMS

This study aimed to develop an anti-aging nanoformulation with Curcuma heyneana extract as bioactive substance.

BACKGROUND

Curcuma heyneana Valeton & Zipj extract has been proven in previous research to have antioxidant, anti-ageing, anti-inflammatory, and wound healing properties, which makes it a potential bioactive material for anti-ageing and sunscreen cosmetic products. Phytoantioxidants need to penetrate into deeper skin layers to ensure effectivity. Thus, a transdermal delivery system is needed to deliver the extract to a deeper skin layer.

OBJECTIVES

The objective of the study was to compare the permeability and anti-ageing activity of liposomal and ethosomal formulations of C. heynena rhizome ethanolic extract.

METHODS

In this study, C. heyneana extract was loaded into a phospholipid vesicular system in the form of liposome and ethosome formulations using the ethanolic injection method. The anti-ageing activity was assessed by analyzing the epidermal thickness, number of sunburn cells, distance between collagen fibers, and number of fibroblasts. While the histologic specimen scoring was carried out for the in vivo penetration study.

RESULTS

The ethosomal formulation had been found to have better penetration ability since it was able to reach the lower dermis area compared to the liposomes, which only reached the upper dermis. The ethosomal formulation of C. heyneana extract exhibited a better anti-ageing activity based on the parameters of epidermal thickness, sunburn cell count, fibroblast count, and the distance between collagen fibres in rat skin histology.

CONCLUSION

Ethosomes have been found to be a more proficient carrier system for transdermal delivery of C. heyneana extract compared to liposomes. Meanwhile, their penetration correlated with the effectivity of the formulation, suggesting that the vesicular system enhanced the penetration ability of the extract.

Sunscreens Containing Cyclodextrin Inclusion Complexes for Enhanced Efficiency: A Strategy for Skin Cancer Prevention

Unprotected exposure of skin to solar ultraviolet radiation (UVR) may damage the DNA of skin cells and can lead to skin cancer. Sunscreens are topical formulations used to protect skin against UVR. The active ingredients of sunscreens are UV filters that absorb, scatter, and/or reflect UVR. Preventing the formation of free radicals and repairing DNA damages, natural antioxidants are also added to sunscreens as a second fold of protection against UVR. Antioxidants can help stabilise these formulations during the manufacturing process and upon application on skin. However, UV filters and antioxidants are both susceptible to degradation upon exposure to sunlight and oxygen. Additionally, due to their poor water solubility, natural antioxidants are challenging to formulate and exhibit limited penetration and bioavailability in the site of action (i.e., deeper skin layers). Cyclodextrins (CDs) are cyclic oligosaccharides that are capable of forming inclusion complexes with poorly soluble drugs, such as antioxidants. In this review, we discuss the use of CDs inclusion complexes to enhance the aqueous solubility of antioxidants and chemical UV filters and provide a protective shield against degradative factors. The role of CDs in providing a controlled drug release profile from sunscreens is also discussed. Finally, incorporating CDs inclusion complexes into sunscreens has the potential to increase their efficiency and hence improve their skin cancer prevention.

Multifunctional Cosmetic Containing Blueberry and Tinosorb M®-Loaded Microparticles Improves Sunscreen Performance

Purpose: We aimed to evaluate the effect of blueberry extract and microparticles (MP) on sunscreen performance of multifunctional cosmetics. Octocrylene (OCT), benzophenone-3 (BENZ-3) and Tinosorb® M (MBBT) were employed as UV filters.

Methods: An in-silico modeling was used to determine the UV filters concentrations to obtain high values of sunscreen protection factor (SPF) and UVA protection factor (UVA-PF). MBBT and blueberry-loaded microparticles (MP_MB+B) and MBBT-loaded microparticles (MP_MBBT) were prepared by spray-drying. OCT and BENZ-3 were added in the oil phase of cosmetics. Cosmetics A and B contained MP_MB+B and MP_MBBT, respectively, and cosmetic C was prepared without MP. Characterization, physicochemical stability and in vitro SPF was performed. UV filters distribution in human stratum corneum (SC) for each cosmetic was performed. Anti-oxidant activity of blueberry extract was evaluated.

Results: Sunscreen combination with the highest SPF was selected for formulations. Formulations A and B maintained their rheological behavior over time, unlike formulation C. In-vitro SPFs for formulations A, B and C were 51.0, 33.7 and 49.6, respectively. We also developed and validated a method for analysis of the UV filters by HPLC/ PDA suitable for the in-vivo assay. In Tape stripping test, MBBT showed SC distribution similar for all cosmetic formulations. OCT and BENZ-3 distribution to formulation A and C was also similar. Blueberry extract showed antioxidant capacity of 16.71 μg/mL equivalent to vitamin C.

Conclusion: Cosmetics containing MPs presented better physical stability. Blueberry increased the photoprotective capacity of the formulations and added extra benefits due to its anti-oxidant and anti-aging properties.

Development and characterization of a nanoemulsion containing propranolol for topical delivery

BACKGROUND

Propranolol (PPN) is a therapeutic option for the treatment of infantile hemangiomas. This study aimed at the development of nanoemulsion (NE) containing 1% PPN, characterization of the system, and safety studies based on ex vivo permeation, cytotoxicity, and biodistribution in vivo.

METHODS

The formulation was developed and characterized in relation to the droplet size, polydispersity index (PDI), pH, zeta potential, and electronic microscopy. Ex vivo permeation studies were used to evaluate the cutaneous retention of PPN in the epidermis and dermis. Cytotoxicity studies were performed in fibroblasts, macrophages, and keratinocytes. In vivo biodistribution assay of the formulations was performed by means of labeling with technetium-99m.

RESULTS

NE1 exhibited droplet size of 26 nm, PDI <0.4, pH compatible with the skin, and zeta potential of -20 mV, which possibly contributes to the stability. Electron microscopy showed that the NE presented droplets of nanometric size and spherical shape. NE1 provided excellent stability for PPN. In the ex vivo cutaneous permeation assay, the NE provided satisfactory PPN retention particularly in the dermis, which is the site of drug action. In addition, NE1 promoted cutaneous permeation of the PPN in small amount. In vivo biodistribution showed that the radiolabeled formulation remained in the skin and a small amount reached the bloodstream. NE1 presented low cytotoxicity to fibroblasts, macrophages, and keratinocytes in the concentrations evaluated in the cytotoxicity assay.

CONCLUSION

We concluded that the formulation is safe for skin administration; however, cutaneous irritation studies should be performed to confirm the safety of the formulation before clinical studies in patients with infantile hemangiomas.

Cyclic Glucans Enhance Solubility of Bioavailable Flavonoids

Diverse flavonoids are abundant in dietary food constituents and possess useful biological activities. However, some flavonoids have limited bioavailability due to their low solubility in water. As an important approach to enhance aqueous solubility, inclusion of hydrophobic guest molecules in hydrophilic hosts such as cyclic glucans has been used. This review summarizes applications of β-cyclodextrin, synthetic β-cyclodextrin derivatives, and newly synthesized derivatives of cyclosophoraoses as complexing agents to enhance the bioavailability of flavonoids such as baicalein, kaempferol, and naphthoflavones.

Comparing in vivo biodistribution with radiolabeling and Franz cell permeation assay to validate the efficacy of both methodologies in the evaluation of nanoemulsions: a safety approach

The Franz cells permeation assay has been performed for over 25 years. However, the advent of nanotechnology created a whole new world, especially with regard to topical products. In this new global scenario an increasing number of nanostructure-based delivery systems (NDSs) have emerged and a global warning relating to the safety of these NDSs is arising. This work studied the efficacy of the Franz cells assay, comparing it with the radiolabeling biodistribution test. For this purpose a formulation of sunscreen based on an NDS was developed and characterized. The results demonstrated both that the NDS did not present in vitro cytotoxicity and that the radiolabeling biodistribution test is more precise for the evaluation of NDS cosmetics than the Franz cells assay, since it detected the permeation of the NDS at a picogram order. Due to this fact, and considering all the concerns related to NDSs and nanoparticles in general, more precise methods must be used in order to guarantee the safe use of these new classes of products.

In vivo and in vitro evaluation of octyl methoxycinnamate liposomes

Solar radiation causes damage to human skin, and photoprotection is the main way to prevent these harmful effects. The development of sunscreen formulations containing nanosystems is of great interest in the pharmaceutical and cosmetic industries because of the many potential benefits. This study aimed to develop and evaluate an octyl methoxycinnamate (OMC) liposomal nanosystem (liposome/OMC) to obtain a sunscreen formulation with improved safety and efficacy by retaining OMC for longer on the stratum corneum.