Nanovesicles for Sensitive Skin Care Developed via Self-Assembly of Glutamine Linoleate.

BACKGROUND

glutamine and linoleic acid (LA) can suppress inflammatory cytokine expression; however, studies on their simultaneous application are limited due to polarity differences.

AIMS

To investigate the effect of glutamine linoleate vesicles (QLAsomes) on skin sensitization by assessing their impact on sensitization-related protein expression, bacterial growth, and clinical efficacy in relieving skin itchiness.

METHODS

After synthesizing and analyzing QLAsomes, their inhibitory effects on capsaicin-induced cytokine expression and Staphylococcus aureus growth were evaluated. In a double-blind clinical trial, 24 participants (ages 22-63) with sensitized skin applied 10 wt% QLAsome cream on one side and a vehicle or no cream on the other twice daily for 2 weeks. Itchiness in the elbow area was assessed using a visual analog scale and expert evaluation. Skin barrier changes were measured using transepidermal water loss (TEWL), skin erythema, and stratum corneum (SC) hydration.

RESULTS

QLAsomes, formed by glutamine and LA through hydrogen bonding, were spherical vesicles (164.6 ± 3.1 nm). Based on the inhibitory effects of glutamine and LA on inflammation-related factors, QLAsomes inhibited the capsaicin-induced expression of these factors more effectively than the individual components. IL-4 inhibition was improved by over 26%. Matrix metalloproteinase-1, which degrades collagen, showed 32% and 23% improvements compared to glutamine and LA, respectively. In a clinical evaluation, 10 wt% QLAsome cream reduced itching by 45% compared to before application, which is a 67% improvement compared to placebo. Skin evaluations revealed improvements in erythema (12%), TEWL (15%), and SC hydration (19%), suggesting that QLAsomes enhance the skin barrier function.

CONCLUSIONS

QLAsomes showed up to 32% higher expression inhibition of key skin sensitization-related factors than individual components, and based on this, improved pruritus by 67% more than placebo. As nanovesicles with skin-soothing properties, they are effective for drug encapsulation and managing skin sensitivity in pharmaceutical and cosmetic industries.