Quantifying the effects of repeated dyeing: Morphological, mechanical, and chemical changes in human hair fibers.

As hair dyeing gains popularity across all age groups, concerns about the potential damage caused by chemical treatments are also on the rise. Chemical dyes have a multifaceted impact on hair fibers, affecting their morphology, physical structure, and protein composition. In a comprehensive study, we investigated the alterations in morphological and mechanical properties, as well as the chemical composition of hair fibers following continuous dyeing.

Titania-Cored Janus Multipods as UV-Protective Pickering Emulsifiers for Sunscreens.

Pickering emulsifiers have gained significant interest as alternatives for conventional surfactants in various applications that includes pharmaceutics, food, homecare products, and cosmetics. However, their function is primarily focused on enhancing emulsion stability of which still remains to be resolved. Herein, Janus multipods are presented that simultaneously shield UV while offering high emulsion stability.

Multilayered collagen-lipid hybrid nanovesicles for retinol stabilization and efficient skin delivery.

Lipid-based nanocarriers have been extensively utilized for the solubilization and cutaneous delivery of water-insoluble active ingredients in skincare formulations. However, their practical application is often limited by structural instability, leading to premature release and degradation of actives. Here we present highly robust multilamellar nanovesicles, prepared by the polyionic self-assembly of unilamellar vesicles with hydrolyzed collagen peptides, to stabilize all-trans-retinol and enhance its cutaneous delivery.

Microencapsulation of alcohol solvents and high-content actives for efficient transdermal delivery.

The barrier function of the skin in effectively protecting the underlying tissue from the surrounding environment makes it challenging to achieve the efficient transdermal delivery of actives. Herein, we report on alcohol-solvent-encapsulated microcapsules to achieve enhanced skin efficacy. We show that using palm oil as the shell material allows for the microencapsulation of a broad range of alcohol solvents, including ethanol and dipropylene glycol (DPG), as well as on-demand release.

Liposome-assisted penetration and antiaging effects of collagen in a 3D skin model.

Background: Collagen is a major component of the extracellular matrix that supports the epidermal layers of the skin; thus, many strategies have been made to enhance the topical delivery of collagen for antiaging purposes. In addition, our previous study indicated that liposome can help the penetration of active ingredients into the skin.

Aims: To produce stable collagen-encapsulated liposomes to improve the topical delivery of collagen.

Hot Water Extract and Its Major Ingredient Hydrangenol Improve Skin Moisturization and Wrinkle Conditions via AP-1 and Akt/PI3K Pathway Upregulation.

is a plant grown in Korea and Japan with a particular natural compound, hydrangenol. has been researched for its anti-fungal properties, and ability to attenuate allergies and promote muscle growth. Its ability to reduce skin dryness is poorly understood.

Highly Robust Multilamellar Lipid Vesicles Generated through Intervesicular Self-Assembly Mediated by Hydrolyzed Collagen Peptides.

Despite the well-known advantages of lipid vesicles for drug and gene delivery, structural instability limits their practical applications and requires strictly regulated conditions for transport and storage. Chemical crosslinking and polymerization have been suggested to increase the membrane rigidity and dispersion stability of lipid vesicles. However, such chemically modified lipids sacrifice the dynamic nature of lipid vesicles and obfuscate their metabolic fates.

Enhanced stability, formulations, and rheological properties of nanoemulsions produced with microfludization for eco-friendly process.

Hypothesis: Eco-friendly processes that are emerging around the world require mass production of low-energy, low-cost nanoemulsions. The process involving the high-concentrated nanoemulsions and diluting them with a large amount of solvent can certainly save the cost; however, not much detailed research has been conducted on the stability mechanism and rheological characteristics of high-concentrated nanoemulsions.

Experiments: In this study, we produced nanoemulsions via the microfluidization (MF) process, comparing their dispersion stability and rheological characteristics with macroemulsions across various oil and surfactant concentrations.

Multilamellar ceramide core-structured microvehicles with substantial skin barrier function recovery.

This study introduces a multilamellar ceramide core-structured microvehicle platform for substantial skin barrier function recovery. Our approach essentially focused on fabricating bacterial cellulose nanofiber (BCNF)-enveloped ceramide-rich lipid microparticles (CerMPs) by solidifying BCNF-armored oil-in-water Pickering emulsions. The oil drops consisted of Ceramide NP (a phytosphingosine backbone -acylated with a saturated stearic acid) and fatty alcohols (FAs) with a designated stoichiometry.

Clinical evaluation of the brightening effect of chitosan-based cationic liposomes.

Background: Cationic liposomes can enhance the permeability of drugs in 3-D skin. Chitosan is considered a safe material for percutaneous delivery; thus, this study uses chitosan-incorporated cationic liposomes.

Aims: This study investigated the improvement in skin brightness, melanin, and melasma after treatment niacinamide-incorporated chitosan cationic liposomes.

Skin Penetration Enhancer-Incorporated Lipid Nanovesicles (SPE-LNV) for Skin Brightening and Wrinkle Treatment.

In this work, we utilize skin penetration enhancers (SPEs) such as ceramide and fatty acids in lipid nanovesicles to promote the transdermal delivery of active ingredients. These SPE-incorporated lipid nanovesicles (SPE-LNV) interact with the constituents of skin's outermost stratum corneum (SC) layer, enabling even niacinamide and adenosine with high water solubility to effectively permeate through, leading to enhanced skin efficacy. We demonstrate by both and skin permeation studies that the SPE-LNV formulation containing both ceramide and fatty acids (LNV-CF) exhibits deeper penetration depth and faster permeation rate compared to conventional lipid nanovesicles (LNV) without SPE as well as LNV-C with only ceramide.

Ultraviolet light screen using cholesteric liquid crystal capsules on the basis of selective reflection.

Sunscreen can protect human skin from sunlight by decreasing exposure to ultraviolet (UV) light, specifically UV-B and UV-A. In this study, a new type of UV screen system is proposed using cholesteric liquid crystal (CLC) capable of selectively reflecting UV-A within the human skin temperature range of 32-36 °C. Polycaprolactone (PCL) capsules with CLC mixture which had a helical chiral pitch corresponding to the wavelength of UV light were made by a solvent evaporation method.

Chronic infrared-A irradiation-induced photoaging of human dermal fibroblasts from different donors at physiological temperature.

Background: In this study, we examined cellular responses to acute and chronic IRA irradiation at mild and natural levels of exposure in two types of human fibroblasts, each isolated from a different donor, at physiological temperature (34°C).

Method: Two types of human dermal fibroblasts (derived from a 20- and 50-year-old women, respectively) were exposed to different repeat numbers of IRA exposure (3, 6, 10, and 14 times; 42 mW/cm ) at a frequency of 3-4 times per week (4 h per irradiation). Cellular responses to acute and chronic IRA irradiation were examined by reactive oxygen species (ROS) level, apoptotic signals, cellular morphology, and collagen level.

Biocompatible Wax-Based Microcapsules with Hermetic Sealing for Thermally Triggered Release of Actives.

We present a microfluidic approach that utilizes temperature-responsive and biocompatible palm oil as the shell material in microcapsules to simultaneously achieve hermetic sealing as well as on-demand temperature-triggered release of the encapsulated actives. Unlike common paraffin waxes (e.g.

Electric fields regulate cellular elasticity through intracellular Ca concentrations.

Cellular elasticity is a key factor related to a broad range of physiological and pathological processes. The elasticity of a single cell has thus emerged as a potential biomarker to characterize the cellular state. Both internal and external stimuli affect cellular elasticity, and changes in elasticity can cause alterations in cellular characteristics or function.

Comparison Study of the Effects of Cationic Liposomes on Delivery across 3D Skin Tissue and Whitening Effects in Pigmented 3D Skin.

Charged phospholipids are employed to formulate liposomes with different surface charges to enhance the permeation of active ingredients through epidermal layers. Although 3D skin tissue is widely employed as an alternative to permeation studies using animal skin, only a small number of studies have compared the difference between these skin models. Liposomal delivery strategies are investigated herein, through 3D skin tissue based on their surface charges.

In vivo determination of the Infrared-A protection factor on human skin.

Background: Chronic exposure to infrared A (IR-A) irradiation causes photoaging. However, daily or acute exposure to IR-A rarely induces erythema or pigmentation. Thus, evaluation of the physiological changes taking place on the skin surface is insufficient for clinical investigations.

Highly Scattering Hierarchical Porous Polymer Microspheres with a High-Refractive Index Inorganic Surface for a Soft-Focus Effect.

Functional light scattering materials have received considerable attention in various fields including cosmetics and optics. However, a conventional approach based on optically active inorganic materials requires considerable synthetic effort and complicated dispersion processes for special refractive materials. Here, we report a simple and effective fabrication strategy for highly scattering hierarchical porous polymer microspheres with a high-refractive index inorganic surface that mitigates the disadvantages of inorganic materials, producing organic-inorganic hybrid particles with an excellent soft-focus effect.

Highly Sustainable and Completely Amorphous Hierarchical Ceramide Microcapsules for Potential Epidermal Barrier.

As a main component of the stratum corneum, ceramides can construct protective lamellae to provide an epidermal barrier against dehydration or external microorganisms. However, as ceramide molecules can easily form the isolated crystalline phase through self-assembly due to the amphipathic nature of bioactive lipids, the effective incorporation of ceramides into liquid media is the remaining issue for controlled release. Here, we report an unprecedented effective strategy to fabricate a completely amorphous and highly sustainable hierarchical ceramide polymer microcapsule for promising epidermal barrier by using the interpenetrating and cooperative self-construction of conical amphiphiles with a different critical packing parameter.

Oleanolic Acid Protects the Skin from Particulate Matter-Induced Aging.

The role of particulate matter (PM) in health problems including cardiovascular diseases (CVD) and pneumonia is becoming increasingly clear. Polycyclic aromatic hydrocarbons, major components of PM, bind to aryl hydrocarbon receptor (AhRs) and promote the expression of CYP1A1 through the AhR pathway in keratinocytes. Activation of AhRs in skin cells is associated with cell differentiation in keratinocytes and inflammation, resulting in dermatological lesions.

Electric field-induced changes in biomechanical properties in human dermal fibroblasts and a human skin equivalent.

Purpose: An electric field (EF) can be used to change the mechanical properties of cells and skin tissues. We demonstrate EF-induced elasticity changes in human dermal fibroblasts (HDFs) and a human skin equivalent and identify the underlying principles related to the changes.

Methods: HDFs and human skin equivalent were stimulated with electric fields of 1.

Cellulose nanofiber-multilayered fruit peel-mimetic gelatin hydrogel microcapsules for micropackaging of bioactive ingredients.

We report a facile but robust approach to fabricate fruit peel-mimetic microcapsules (FPMCs) of which shell was structured by layering cellulose nanofibers (CNFs) with an antioxidant and a waxy compound on monodisperse gelatin microparticles using the layer-by-layer deposition. The thickness and moduli of the shell increased commonly depending on the number of CNF layers, indicating that the incorporation of CNFs made the shell layer rigid. We determined that the coating of the outermost FPMC layer with dodecane nanoemulsions softened the shell surface, thus preventing the generation of microcracks, which is essential for minimizing dehydration in the drying process.

A novel in vivo test method for evaluating the infrared radiation protection provided by sunscreen products.

Background: Infrared radiation (IR) exposure generates reactive oxygen species and induces matrix metalloproteinase-1 expression in human skin. Moreover, while not as acute as ultraviolet radiation, repeated infrared irradiation can result in the photoaging of skin. Broad-spectrum sunscreens can protect skin from IR, but no human in vivo test methods for the evaluation of sunscreens' IR protection effect have been developed.