Seeking better topical delivery technologies of moisturizing agents for enhanced skin moisturization

ABSTRACT

Introduction: An adequate hydration level is essential to maintain epidermal barrier functions and normal physiological activities of skin tissues. Diverse moisturizing agents and pharmaceutical formulations for dermal deliveries have thus extensively been investigated. This review comprehensively discusses scientific outcomes of moisturizing agents and pharmaceutical vehicles for skin moisturization, thereby providing insight into designing innovative pharmaceutical formulations for effective skin moisturization.

Areas covered: We discussed the functions of various moisturizing agents ranging from conventional creams to novel moisturizers which has recently been explored. In addition, novel pharmaceutical formulations for efficient dermal delivery of the moisturizers, in particular, nanocarriers, were discussed along with their uses in commercial products.

Expert opinion: Although various moisturizing agents have demonstrated their promising effects, exploitation of pharmaceutical formulations for their dermal delivery have been limited to few commonly used moisturizing agents. Thus, combinatorial investigation of novel moisturizers and pharmaceutical vehicles should be further conducted. As a new concept for improving skin moisturization, skin regeneration technologies using therapeutic cells have recently shown great promise for skin moisturization, but major challenges remain, such as efficient delivery and prolonged survival of such cells. Thus, novel approaches for improving skin moisturization require continuous efforts of pharmaceutical scientists to address the remaining problems.

KEYWORDS:

• Skin moisturization
• moisturizing agent
• pharmaceutical formulation
• skin barrier
• natural moisturizing factor
• stratum corneum
• barrier enhancer

Article highlights

• Beyond conventional moisturizers such as occlusive and humectants, novel moisturizing agents with different functions have been investigated, providing great opportunities to enhance skin moisturization.

• Various pharmaceutical formulations, in particular, nanocarriers, can be exploited to deliver moisturizing agents to the skin tissues of interest with high efficiency.

• In vitro and in vivo studies have demonstrated that efficient delivery of moisturizing agents to the skin by suitable pharmaceutical vehicles can considerably improve and prolong skin moisturization.

• There is a gap in current research regarding combinatorial investigations of novel moisturizing agents and pharmaceutical vehicles.

• As a new concept for improving skin moisturization, skin regeneration technologies using therapeutic cells have been emerging, although efficient delivery and prolonged survival of the cells have posed major challenges.

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Declaration of interest

The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Additional information

Funding

This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (No. 2015R1A5A1008958). This work was also supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (No. 2015R1D1A1A02062278).