International Journal of Cosmetic Science最新文献

Objective: To evaluate whether p-hydroxycinnamic acid (pHCA) alone and in combination with niacinamide (Nam) can mitigate UV-induced erythema, barrier disruption, and inflammation.

Methods: Three independent placebo-controlled double-blinded studies were conducted on female panellists who were pretreated on sites on their backs for 2 weeks with skin care formulations which contained 0.3% or 1% pHCA with 5% Nam, 1% pHCA alone, 1.8% octinoxate, or control formula. Treated sites were then exposed to 1.5 minimal erythemal dose (MED) solar simulated radiation (SSR) and had chromameter and expert grading measures for erythema, barrier integrity via TEWL, and the skin surface IL-1RA/IL-1α inflammatory biomarkers isolated from D-Squame tapes.

Results: Across the three independent studies, pHCA alone or in combination with Nam showed a significant mitigation of UV-induced erythema, barrier disruption, and levels of the surface inflammatory biomarkers IL-1RA/IL-1α. The cinnamate analogue Octinoxate did not replicate the effects of pHCA.

Conclusion: The study results show that pHCA alone or in combination with Nam can mitigate UV-induced damage to skin. These include mitigation of UV-induced erythema as measured by instrument and expert grade visualization. Additionally, pHCA with Nam protected damage to the barrier and reduced the induction of the SASP-related surface inflammatory biomarker IL-1RA/IL-1α. The inability of Octinoxate to have any protective effect and the detection of low levels of pHCA on skin surface after 24 h of application supports that these effects are based on a biological response to pHCA. These findings add to the body of evidence that pHCA alone or in combination with Nam can enhance the skin's biological response to UV-induced damage. This supports pHCA can potentially impact aging and senescence, thereby maintain skin's functionality and appearance.

Objective: Prosopis juliflora, commonly known as algaroba or mesquite, was introduced and has since proliferated throughout the semi-arid region of the Caatinga biome. Various studies have documented its properties, including antimicrobial, antioxidant, and antitumor activities, attributed to the presence of diverse secondary metabolites such as alkaloids, terpenoids, tannins, and flavonoids. The objective of this study was to evaluate the antioxidant and antityrosinase activities of P. juliflora fruit extract as a multifunctional active ingredient, and to develop cosmetic formulations containing this vegetal extract for potential applications in skincare products targeting pro-ageing and skin colour homogenization properties.

Methods: The extraction process followed established protocols. Chemical characterization of the extract involved quantification of total flavonoids and phenolic compounds, along with Liquid Chromatography-Mass Spectrometry (LC-MS) analysis. In vitro antioxidant activity was assessed using different methods. Antityrosinase activity was determined by employing enzymatic assays. Cosmetic formulations containing Disodium EDTA, Phenoxyethanol (and) Ethylhexyl Glycerin, Distilled Water, Sodium Acrylates Copolymer Lecithin, Polyacrylamide (and) C13-14 Isoparaffin (and) Laureth-7, and 3.0% of the investigated plant extract were subjected to preliminary and accelerated stability tests.

Results: The extract demonstrated a concentration of total flavonoids (1.71 ± 0.26 μg EQ/mg) and exhibited concentrations of phenolic compounds at 0.21 ± 0.01 mg EAG/g. Metabolites such as flavonoids and saponins were annotated, as well as some of their respective glycosidic derivatives. The extract showed antioxidant potential and the ability to inhibit the oxidation cascade in both the initiation and propagation phases. Moreover, the extract exhibited noteworthy inhibition of antityrosinase activity, presenting 62.48 ± 2.09 at a concentration of 30.00 mg/mL. The formulations were stable in accelerated stability tests over a 60-day period.

Conclusion: This research not only demonstrates scientifically by demonstrating the potential of a plant from the Caatinga biome with antioxidant and antityrosinase properties in the development of cosmetic products aimed at pro-ageing effects and skin colour harmonization, but also adds value to the P. juliflora production chain. This valorization encompasses various aspects which include environmental, social, and biodiversity responsibilities.

Background: Use of permanent hair dyes causes unintended oxidative damage during the short time frame of the dyeing process that leads to perceivable changes in the feel, manageability and appearance of hair. Moreover, after hair has been dyed, regular exposure to the sun as a key environmental stressor continues to stimulate additional oxidative damage and to induce newly developed hair colours to fade prematurely or undergo changes in colour quality.

Objective: To document the utility of acetyl zingerone methyl ether (MAZ) as a newly designed haircare ingredient to afford extra protection against oxidative damage and safeguard the integrity of hair colour.

Results: We demonstrate that MAZ is compatible chemically with the high alkaline conditions required for the colouring process and from theoretical calculations preferentially binds Fe and Cu ions relative to Ca or Zn ions. In model Fenton reactions MAZ effectively chelated active redox metals (Fe and Cu ions) in the presence of excess Ca⁺² ions to inhibit the production of hydroxyl radicals, and in separate studies, MAZ neutralized singlet oxygen with greater efficiency than α-tocopherol by a factor of 2.5. When mixed into permanent dyes prior to hair tress application, MAZ significantly reduced combing forces, and SEM images led to substantial reductions in visual signs of surface damage. In a 28-day clinical study, relative to controls, mixing MAZ into hair dyes prior to application interfered neither with colour development nor with ability to cover grey hair and led to significant improvements in perceived attributes associated with hair's condition immediately following the dyeing process. Over a 28-day maintenance phase, especially between Day 14 and Day 28, continued use of shampoo and conditioner containing MAZ significantly preserved gloss measurements and hair colour in terms of longevity and colour quality as remaining desired and fresh compared to use of control shampoo and conditioner.

Conclusion: This work establishes MAZ as a next-generation hair care ingredient for use in permanent dyes to attenuate oxidative damage and in shampoos and conditioners to promote longevity of hair colour and to maintain overall health and appearance of hair on a daily basis.

Objective: This research investigates how particle parameters, such as zeta potential, size, functional group, material composition, and hydrophobicity affect their affinity and deposition of particles onto hair.

Methods: Streaming potential was used as the technique for analysis. The streaming potential data obtained was then converted to surface coverage data. Scanning electron microscopy (SEM) was also done to visualize particle localization on the hair surface.

Results: This study found stronger particle affinity on healthy than on damaged (oxidatively bleached) hair, due to diminished interaction sites from the removal of the hair shaft's external lipid layer. SEM imaging supported these findings and offered insights into particle localization. Hydrophilic silica particles accumulated along the exposed hydrophilic cuticle edges of healthy hair, due to hydrogen bonding with the exposed endocuticle. This localization is hypothesized to be due to the limited hydrophilic binding sites on the hydrophobic healthy hair cuticle surface. In damaged hair, an abundance of hydrophilic sites across the cuticle surface results in more dispersed binding. Hydrogen bonding and electrostatic attraction were shown to be the predominant forces influencing deposition, with hydrophobic interactions playing a less influential role. The affinity studies also proved that electrostatic attractions work over a longer range and are more effective at lower particle conditions compared with hydrogen bonding which only start to play a bigger role at higher particle concentrations. Steric hindrance of bulky side groups acted as a significant repulsive force. Results also revealed that larger particles deposit poorly on both healthy and damaged hair compared with smaller ones. Compared with neutrally charged silica nanoparticles (SN-2), positively charged PMMA particles (PN+16) have a stronger affinity to healthy hair, with highly charged particles (PN+49) depositing most rapidly.

Conclusion: This study provides a fundamental understanding of how particle-surface parameters influence their affinity to hair and how damaging hair affects deposition.

Objective: Hydrolyzed conchiolin protein (HCP) derived from pearl and nacre extracts exerts skin-lightening effects; however, the underlying molecular mechanisms are not fully understood. Herein, we investigated the effect of HCP on melanogenesis and the signalling pathways involved.

Methods: B16F10 cells and PIG cells were treated with HCP to verify its ability to inhibit melanin. Western Blot, immunofluorescence, and flow cytometry methods were performed to investigate the effect of HCP on melanogenesis signalling pathway proteins. The inhibitors were used to further validate the effect of HCP on PKA/CREB and MEK/ERK signalling pathways. To further evaluate the whitening ability of HCP, changes in melanin were detected using 3D melanin skin model and zebrafish model.

Results: HCP was found to significantly inhibit melanin synthesis and decrease the expression of melanogenesis-related proteins, such as microphthalmia-associated transcription factor (MITF), tyrosinase, and tyrosinase-related protein-2, in a dose-dependent manner. Additionally, we revealed that HCP suppresses melanogenesis via the regulation of the PKA/cAMP response element-binding (CREB) and MEK/extracellular signalling-regulated kinase (ERK) signalling pathways. Using 3D melanin skin models, we demonstrated that HCP can achieve skin-lightening effects by improving apparent chroma, increasing apparent brightness, and inhibiting melanin synthesis. Furthermore, HCP exhibits skin-whitening effects in a zebrafish model.

Conclusion: These results suggest that HCP suppresses the melanogenesis signalling cascade by inhibiting the PKA/CREB, MEK/ERK signalling pathway and downregulating MITF and its downstream signalling pathways, resulting in decreased melanin synthesis. In summary, HCP is a potential anti-pigmentation agent with promising applications in cosmetics and pharmaceutical products.

The inevitable attrition of skin due to ultraviolet radiation, termed photoaging, can be partially restored by treatment with retinoid compounds. Photoaged skin in lightly pigmented individuals, clinically presents with the appearance of wrinkles, increased laxity, and hyper- and hypopigmentation. Underlying these visible signs of ageing are histological features such as epidermal thinning, dermal-epidermal junction flattening, solar elastosis and loss of the dermal fibrillin microfibrillar network, fibrillar collagen and glycosaminoglycans. Retinoid compounds are comprised of three main generations with the first generation (all-trans retinoic acid, retinol, retinaldehyde and retinyl esters) primarily used for the clinical and cosmetic treatment of photoaging, with varying degrees of efficacy, tolerance and stability. All-trans retinoic acid is considered the 'gold standard' for skin rejuvenation; however, it is a prescription-only product largely confined to clinical use. Therefore, retinoid derivatives are readily incorporated into cosmeceutical formulations. The literature reported in this review suggests that retinol, retinyl esters and retinaldehyde that are used in many cosmeceutical products, are efficacious, safe and well-tolerated. Once in the skin, retinoids utilize a complex signalling pathway that promotes remodelling of photoaged epidermis and dermis and leads to the improvement of the cutaneous signs of photoaging.

Objective: Periorbital skin ageing signs are multidimensional, highly visible and a concern for many. We evaluated the potential efficacy of an eye cream to diminish these signs.

Methods: Biological markers associated with ageing, barrier function and homeostasis were analysed in vitro to determine the effects of topically applied eye cream, compared to those of a placebo using human skin tissue models and/or explants. Collagen IV, elastin and bone morphogenic protein 4 (BMP4) expression was investigated by immunohistochemical labelling, while filaggrin, kallikrein 7 (KLK7) and HB-EGF were evaluated by RT-qPCR. IL-1α and melanin levels in darkly pigmented skin models were also quantified. The protective effect of the cream on glycation was assessed by a non-enzymatic assay. Finally, the benefits of twice-daily applications of the eye cream for 56 days were instrumentally and clinically evaluated on 33 women.

Results: Only the eye cream, not the placebo, stimulated collagen IV and BMP4 protein expression, as well as increased elastin fibre length. It also led to higher HB-EGF, filaggrin and KLK7 mRNA levels. The placebo and the eye cream did not induce changes in IL-1α and melanin levels, but both reduced non-enzymatic glycation. When assessing the in vivo effects of the cream, short-term results indicated skin hydration, transepidermal water loss (TEWL) and skin profilometry improvement within 15 min. Instrumental evaluations of wrinkles showed a reduction after 7 days, which was clinically perceivable after 28 or 56 days. The eye-opening angle and eyelid sagging also improved after seven and 28 days, respectively. Finally, dark circles became lighter within 7 days (instrumental measurement) or 28 days (clinical assessment).

Conclusion: The instrumental and clinical evaluations revealed that the eye cream reduced all periorbital ageing signs evaluated. Its effects are supported by the in vitro and ex vivo analyses of molecular markers.

Objective: The objective is to develop a natural and stable anti-oxidative stress and anti-ageing ingredient. In this study, we evaluated the changes in white tea leaves fermented with Eurotium cristatum PLT-PE and Saccharomyces boulardii PLT-HZ and their efficacy against skin oxidative stress.

Methods: We employed untargeted metabolomics technology to analyse the differential metabolites between tea extract (TE) and fermented tea extract (FTE). In vitro, using H₂O₂-induced HaCaT cells, we evaluated cell vitality, ROS, and inflammatory factors (TNF-α, IL-1β, and IL-6). Additionally, we verified the effects on the extracellular matrix and nuclear DNA using fibroblasts or reconstructed skin models. We measured skin hydration, elasticity, wrinkle area, wrinkle area ratio, erythema area, and erythema area ratio in volunteers after using an emulsion containing 3% FTE for 28 and 56 days.

Results: Targeted metabolomics analysis of white tea leaves yielded more than 20 differential metabolites with antioxidant and anti-inflammatory activities, including amino acids, polypeptides, quercetin, and liquiritin post-fermentation. FTE, compared to TE, can significantly reduce reactive oxygen species (ROS) and protect against oxidative stress-induced skin damage in H₂O₂-induced HaCaT cells. FTE can inhibit H₂O₂-induced collagen degradation by suppressing the MAPK/c-Jun signalling pathway and can also mitigate the reactive oxygen species damage to nuclear DNA. Clinical studies showed that the volunteers' stratum corneum water content, skin elasticity, wrinkle area, wrinkle area ratio, erythema area, and erythema area ratio significantly improved from the baseline after 28 and 56 days of FTE use.

Conclusion: This study contributes to the growing body of literature supporting the protective effects against skin oxidative stress and ageing from fermented plant extracts. Moreover, our findings might inspire multidisciplinary efforts to investigate new fermentation techniques that could produce even more potent anti-ageing solutions.

The stratum corneum (SC), the outermost epidermal layer, plays a pivotal role in skin barrier function. This review delves into the intricate process of protein degradation within the stratum corneum, elucidating the roles of specific enzymes, regulatory mechanisms and the consequent impact on various skin conditions. Protein degradation is a finely tuned process, orchestrated by a suite of proteolytic enzymes like kallikreins. These enzymes are responsible for the breakdown of corneodesmosomes and the orderly desquamation of corneocytes, a process essential for skin homeostasis. Another critical enzymatic process is the breakdown of proteins like filaggrin and the generation of amino acids and their derivatives, required in the physiological water-handling properties of the SC. Regulation of these proteolytic activities is complex, involving a balance between endogenous inhibitors and other factors like pH, hydration and environmental stressors. Dysregulation of protease activity is linked to a spectrum of skin conditions, ranging from xerosis to inflammatory diseases like atopic dermatitis and psoriasis. Aberrant protein degradation can lead to compromised skin barrier function, increased tissue water loss and heightened susceptibility to infections and allergens. Understanding the factors affecting protein degradation can inform the development of targeted skincare products. Advances in biochemistry and dermatology have paved the way for the search for active ingredients designed to modulate protease activity. Such innovations may offer promising therapeutic avenues for enhancing skin barrier function and treating skin disorders. This review underscores the significance of enzymatic protein degradation in the SC and its regulatory mechanisms. It provides insights into the pathophysiology of skin diseases and outlines the potential for novel skincare interventions. By bridging the gap between fundamental research and practical applications, this article aims to inspire further investigation for better understanding of skin physiology and innovation in the realm of skincare product development.