Effects of Collagen Tripeptide Supplement on Photoaging and Epidermal Skin Barrier in UVB-exposed Hairless Mice

Effects of Collagen Supplements on Skin Aging: A Systematic Review and Meta-analysis of Randomized Controlled Trials

BACKGROUND

Collagen supplements are promoted to help aging skin. However, no meta-analysis of randomized controlled trials (RCTs) has examined their effects by funding source and study quality, which may influence outcomes.

METHODS

PubMed, Embase, and Cochrane Library were searched from inception to June 14, 2024.

RESULTS

A total of 23 RCTs with 1474 participants were analyzed. In a meta-analysis of all 23 RCTs, collagen supplements significantly improved skin hydration, elasticity, and wrinkles. However, in the subgroup meta-analysis by funding source, studies not receiving funding from pharmaceutical companies revealed no effect of collagen supplements for improving skin hydration, elasticity, and wrinkles, while those receiving funding from pharmaceutical companies did show significant effects. Similarly, high-quality studies revealed no significant effect in all categories, while low-quality studies revealed a significant improvement in elasticity.

CONCLUSIONS

There is currently no clinical evidence to support the use of collagen supplements to prevent or treat skin aging.

Effective release of Eryngium maritimum L. callus extract via encapsulation in multilayered liposomes for skin delivery

AIMS

This study aimed to evaluate the potential of Eryngium maritimum L. (EM) callus media filtrate (ECMF) for enhanced skin delivery through multilayered liposomes (MLs).

MATERIALS & METHODS

ECMF was applied to human skin cells to assess its antioxidant, anti-inflammatory, and skin barrier-enhancing properties. ECMF was encapsulated in MLs to enhance delivery efficiency, creating a formulation called Cellbiome. Clinical trials involving human participants were conducted to compare its effects with traditional formulations, assessing parameters such as skin density, hydration, elasticity, and wrinkle reduction.

RESULTS

Cellbiome significantly improved skin density and moisturization, outperforming conventional formulations. ML encapsulation facilitated deeper penetration of active ingredients beyond the stratum corneum, leading to synchronized improvements in multiple skin parameters, including elasticity, wrinkle reduction, and overall skin health. Transcriptomic and metabolomic analyses further confirmed ECMF's bioactivity and its role in skin improvement.

CONCLUSIONS

ML-based formulations, such as Cellbiome, offer superior efficacy in skincare applications compared to conventional methods. This study underscores the importance of advanced delivery technologies in cosmetics and highlights the need for further research to optimize the benefits of natural extracts like EM for human skin, potentially advancing dermatological and cosmeceutical applications.

Oyster hydrolysate ameliorates UVB-induced skin dehydration and barrier dysfunction

Ultraviolet (UV) exposure triggers skin aging primarily by disrupting skin barrier function, resulting in dry skin and wrinkle formation. Oyster hydrolysate (OH), as a functional food, has been reported for anti-cancer, anti-oxidant and anti-apoptotic effects. This study investigated the underlying mechanism of OH effect on UVB-induced skin aging in SKH1 hairless mice. Mice were exposed to UVB three times per week while they were fed with a normal diet or diet containing OH for 10 weeks. Additionally, a randomized, double-blind, and placebo-controlled clinical trial was performed to investigate the OH effect on human skin moisturizing to evaluate its efficacy and safety. UVB exposure increased parameters of skin aging; dehydration, transepidermal water loss, and macroscopic dorsal skin lesions. OH significantly reduced these features of skin aging. Histological analysis demonstrated that OH decreased skin epidermal and dermal thickness and collagen degradation induced by UVB. OH significantly reduced ROS production, suppressed macrophage activation and neutrophil infiltration, and downregulated pro-inflammatory cytokine production. OH improved skin barrier function by increasing the expression of filaggrin, aquaporin-3, and hyaluronic acid synthesis enzymes and promoting recovery from skin damage. Importantly, the results from a human clinical trial demonstrated that OH improved skin moisturization and integrity with no side effects. Taken together, OH supplementation ameliorates skin damage via anti-oxidant and anti-inflammatory properties and enhances skin hydration and barrier function. OH has a therapeutic potential for skin photoaging.

Oral Intake of Collagen and Collagen Hydrolysate From Takifugu bimaculatus Attenuates Ultraviolet-Induced Skin Photoaging in Mice

With the rapid emergence of pufferfish aquaculture and processing industries, fish skin is underutilized as a byproduct of processing, leading to resource waste. In this study, Takifugu bimaculatus skin collagen (TBSC) was extracted by acetic acid solubilization and its physicochemical properties were analyzed. The effects of TBSC and the TBSC hydrolysate (TBSCH) on ultraviolet (UV) irradiation-induced photoaging were investigated using a mouse model. The purity of TBSC was 90.02%. Electrophoresis and Fourier infrared spectroscopy characterization of TBSC showed that the type of collagen in TBSC was typical standard type I. The degree of hydrolysis was selected to optimize the hydrolysis conditions for TBSC. The papain enzyme dosage, temperature, pH, and hydrolysis duration of 51,000 U/g, 48.03°C, 5.35, and 4 h have been demonstrated to be the optimum hydrolysis conditions for TBSCH. Oral administration of either TBSC or TBSCH ameliorated UV-induced skin erythema and hyperkeratosis. TBSC and TBSCH treatment increased collagen content and had an inhibitory effect on matrix metalloproteinase (MMP)-2 and MMP-3 expression, whereas MMP-9 expression was significantly reversed only in the TBSCH-treated groups. The expression of the c-Jun protein was much lower in these groups, suggesting that TBSCH had a greater alleviating effect on collagen degradation and extracellular matrix breakdown. Therefore, it is proposed that TBSCH has the potential to be used as a nutricosmetic agent with protective attributes against UV-induced skin damage and concurrent collagen depletion.

Food-derived skin-care ingredient as a promising strategy for skin aging: Current knowledge and future perspectives

Skin aging involves complex biochemical reactions and has attracted a growing concern recently. For it, there is a great desire to replace the hazardous and easy-recurring "therapy means" with "daily care" based on some natural and healthy ingredients. According to a novel theory called "homology of cosmetic and food", the safety, efficacy and accessibility of food-derived skin-care ingredients offer an attractive option for combating skin aging, which will be an inevitable trend of dermatology in the future. Ultraviolet (UV) radiation is a major trigger of skin aging. It acts on the skin and generates reactive oxygen species, which causing oxidative stress. More, matrix metalloproteinase and melanin levels are also upregulated by the UV-activated mitogen-activated protein kinase (MAPK) pathway and tyrosinase, respectively, resulting in collagen degradation and melanin deposition in the extracellular matrix. Through the existing studies, the relevant key biomarkers and biochemical pathways can be effectively controlled by skin-care ingredients from animal-derived and plant-derived foods as well as traditional herbs, thus preserving human skin from UV-induced aging in terms of antioxidant, collagen protection and melanin inhibition. To extend their application potential, some carriers represented by nanoliposomes can facilitate the transdermal absorption of food-derived skin-care ingredients by the variation of molecular weight and lipid solubility. The present review will provide an overview of the trigger mechanisms of skin aging, and focus on the molecular biology aspects of food-derived skin-care ingredients in skin matrix and the critical summarize of their research state.

Dihydroavenanthramide D Enhances Skin Barrier Function through Upregulation of Epidermal Tight Junction Expression

Skin barrier dysfunction and thin epidermis are hallmarks of sensitive skin and contribute to premature aging. Avenanthramides are the primary bioactive components of colloidal oatmeal, a commonly used treatment to enhance skin barrier function. This study investigated the relationship between skin barrier function and epidermal characteristics and explored the potential of dihydroavenanthramide D (dhAvD), a synthetic avenanthramide, to improve the skin barrier. We observed a significant correlation between impaired skin barrier function and decreased epidermal thickness, suggesting that a weakened barrier contributes to increased sensitivity. Our in vitro results in HaCaT cells demonstrated that dhAvD enhances keratinocyte proliferation, migration, and tight junction protein expression, thereby strengthening the skin barrier. To mimic skin barrier dysfunction, we treated keratinocytes and full-thickness skin equivalents with IL-4 and IL-13, cytokines that are implicated in atopic dermatitis, and confirmed the downregulation of tight junction and differentiation markers. Furthermore, dhAvD treatment restored the barrier function and normalized the expression of key epidermal components, such as tight junction proteins and natural moisturizing factors, in keratinocytes treated with inflammatory cytokines. In the reconstructed human skin model, dhAvD promoted both epidermal and dermal restoration. These findings suggest that dhAvD has the potential to alleviate skin sensitivity and improve skin barrier function.

Comprehensive Biosafety Profile of Carbomer-Based Hydrogel Formulations Incorporating Phosphorus Derivatives

Determining the safety of a newly developed experimental product is a crucial condition for its medical use, especially for clinical trials. In this regard, four hydrogel-type formulations were manufactured, all of which were based on carbomer (Blank-CP940) and encapsulated with caffeine (CAF-CP940), phosphorus derivatives (phenyl phosphinic (CAF-S1-CP940) and 2-carboxyethyl phenyl phosphinic acids (CAF-S2-CP940)). The main aim of this research was to provide a comprehensive outline of the biosafety profile of the above-mentioned hydrogels. The complex in vitro screening (cell viability, cytotoxicity, morphological changes in response to exposure, and changes in nuclei morphology) on two types of healthy skin cell lines (HaCaT-human keratinocytes and JB6 Cl 41-5a-murine epidermal cells) exhibited a good biosafety profile when both cell lines were treated for 24 h with 150 μg/mL of each hydrogel. A comprehensive analysis of the hydrogel's impact on the genetic profile of HaCaT cells sustains the in vitro experiments. The biosafety profile was completed with the in vivo and in ovo assays. The outcome revealed that the developed hydrogels exerted good biocompatibility after topical application on BALB/c nude mice's skin. It also revealed a lack of toxicity after exposure to the hen's chicken embryo. Further investigations are needed, regarding the in vitro and in vivo therapeutic efficacy and safety for long-term use and potential clinical translatability.

Upcycled canola meal extract mitigates UVB-induced skin wrinkling by regulating photoaging-related biomarkers in hairless mice

Canola meal, a by-product of processing canola into oil, reportedly contains high amounts of phenolic compounds and proteins. However, as canola meal is primarily used as feed for livestock, advances in multiple research fields are required to broaden its potential applications. Photoaging is caused by continuous exposure to ultraviolet (UV) radiation from sunlight. UV radiation generates reactive oxygen species and destroys collagen in the skin, thickening the epidermis, reducing elasticity, and causing wrinkles. We hypothesized that canola meal extract (CME) can mitigate the damage to skin associated with wrinkles induced by exposure to UVB radiation. To evaluate the anti-wrinkle effect, we administered CME orally to 40 female Hos:HR-1 hairless mice divided into 5 groups: (1) control mice, (2) a UVB group, and (3-5) CME-treated groups (CME-250, 500, and 1000 mg/kg body weight/day, respectively). All groups except the controls were irradiated with UVB 3 times a week to create wrinkles due to photoaging. CME administration inhibited the increase of the number, mean length, and mean depth of wrinkles induced by UVB radiation as assessed using a skin replica. Histopathological image analysis revealed that CME administration resulted in a decrease in epidermal thickness and an increase in collagen content, while increasing catalase activity and hydroxyproline content in skin tissues. CME administration inhibited the phosphorylation of mitogen-activated protein kinase and decreased the production of collagenase and gelatinase. These results suggest that CME, an upcycled material, has the potential to develop into a healthful and functional food ingredient with anti-wrinkling effects.

Liquid collagen from freshwater fish skin ameliorates hydration, roughness and elasticity in photo-aged skin: a randomized, controlled, clinical study

BACKGROUND/OBJECTIVES

Collagen is commonly used in diverse forms as a functional component in skincare products. On the other hand, the effects of collagen on human skin are controversial. Dietary collagen hydrolysates from freshwater Pangasius hypophthalmus fish skin ameliorated photo-aged skin of hairless mice. This study conducted a randomized, double-blind, placebo-controlled clinical trial to determine if liquid fish collagen (Collagen-Tripep20™, Tripep20) as a drink strengthens skin health and quality.

SUBJECTS/METHODS

In this clinical trial, 85 subjects aged 35-60 yrs were diagnosed with photo-aged skin. Eighty-five subjects were randomized to receive either Tripep20 (n = 44) or placebo (n = 41). Seventy-eight subjects fully participating for a 12-week period consumed 1,000 mg of Tripep20 (n = 41) or placebo (n = 37) in a 50-mL bottle as a daily drink. The intend-to-treat and per-protocol populations were 85 and 78, respectively. Skin hydration, wrinkles, and elasticity were assessed at 0 (baseline), 6, and 12 weeks during the study period.

RESULTS

Skin hydration in the Tripep20 group was significantly higher from 6 weeks (P < 0.001) than the baseline. After 12 weeks, the Crow's-feet visual score and skin roughness (Ra, Rq, and Rmax) were significantly improved in the Tripep20 group than in the placebo group (P < 0.05). Consuming liquid collagen Tripep20 greatly enhanced skin elasticity (Gross R2, Net R5, and Biological elasticity R7) in 6 weeks compared to the placebo group. The Tripep20 group showed a significant increase in skin elasticity from the baseline after 6 and 12 weeks (P < 0.001). Neither abnormal symptoms nor adverse events were encountered during the study period in subjects ingesting Tripep20 or placebo. The changes in parameters related to hematology and clinical chemistry were within the normal ranges.

CONCLUSION

Oral consumption of liquid collagen Tripep20 was safe and well-tolerated. The results of this study show that freshwater fish-derived liquid collagen Tripep20 can be used as a healthy functional food ingredient to improve skin moisturizing, anti-wrinkling, and elasticity in an aging population.

Effects of Hydrolyzed Collagen as a Dietary Supplement on Fibroblast Activation: A Systematic Review

BACKGROUND

Our objective was to conduct a systematic review of the effects of hydrolyzed collagen supplementation on the proliferation and activation of fibroblasts.

METHODS

The search was conducted for journals that published articles in the English language, peer-reviewed, meeting the following criteria: (a) randomized clinical trials, (b) randomized studies in animals or humans, (c) in vitro studies, (d) studies using hydrolyzed collagens or collagen peptides, and (e) studies assessing alterations on fibroblasts as the primary or secondary outcome. We utilized the main journal databases PubMed/Web of Science and ongoing reviews by PROSPERO. For bias risk and methodological quality, we used an adaptation of the Downs and Black checklist. Our review followed the PRISMA checklist, conducted from February 2024 to the first week of March 2024, by two independent researchers (P.A.Q.I. and R.P.V.).

RESULTS

Eleven studies were included in this review, where our findings reinforce the notion that hydrolyzed collagens or collagen peptides at concentrations of 50-500 μg/mL are sufficient to stimulate fibroblasts in human and animal tissues without inducing toxicity. Different enzymatic processes may confer distinct biological properties to collagens, allowing for scenarios favoring fibroblast promotion or antioxidant effects. Lastly, collagens with lower molecular weights exhibit greater bioavailability to adjacent tissues.

CONCLUSIONS

Hydrolyzed collagens or collagen peptides with molecular sizes ranging from <3 to 3000 KDa promote the stimulation of fibroblasts in human tissues.

Preventive and Therapeutic Benefits of Natural Ingredients in Photo-Induced Epidermal Dysfunction

BACKGROUND

The skin, particularly the epidermis, is subjected to various external stresses, including ultraviolet (UV) irradiation. UV irradiation, mainly UVB at wavelength of 280-315 nm, can alter several epidermal functions, including cutaneous inflammation, epidermal hyperproliferation, DNA damage, disruption of epidermal permeability barrier and reduction in stratum corneum hydration levels. Because of the negative impacts of UVB irradiation on epidermal functions, great efforts have been made to develop regimens for the protection of alterations in epidermal function induced by UV irradiation.

SUMMARY

While sunscreen can provide physical barrier to UV light, some natural ingredients can also effectively protect the skin from UVB irradiation-induced damages. Studies have demonstrated that either topical or oral administrations of some natural ingredients attenuate UVB irradiation-induced alterations in the epidermal function. The underlying mechanisms by which natural ingredients improve epidermal functions are attributable to antioxidation, stimulation of keratinocyte differentiation, increases in the content of epidermal natural moisturizers and inhibition of inflammation.

KEY MESSAGE

Some natural ingredients exhibit protective and therapeutical benefits in photo-induced epidermal dysfunctions via divergent mechanisms.

Gold nanobipyramids-based laser-activated sealants for effective skin sealing and repair

Anisotropic gold nanostructures have gained increased attention for biomedical applications because of their remarkable optical properties. An emerging type of gold nanostructure-gold nanobipyramids (AuNBP)-has been shown to exhibit superior absorption properties compared to conventionally used gold nanoparticles, which makes them attractive for photothermal applications. We generated a high-shape-purity dispersion of AuNBP using a seed-mediated method and embedded them as photothermal conversion agents in a silk fibroin matrix to investigate their efficacy in photothermal sealing of incisional wounds in immunocompetent mice. These AuNBP-doped laser-activated sealants, or AuNBP-LASE were able to absorb near-infrared laser energy and convert it to heat, thereby inducing transient hyperthermia in the wound and the surrounding tissue. This photothermal conversion facilitated rapid sealing of the skin tissue by the AuNBP-LASE, which resulted in faster functional recovery of skin barrier function compared to nylon sutures at the early stages of repair. Further, the biomechanical properties of the healing skin closed with AuNBP-LASE those of intact skin more rapidly compared to incisions approximated with sutures. Histology studies indicated higher penetration of the LASE within the volume of the incision in skin tissue, lower scab formation, and a similar epidermal gap compared to conventional suturing. These results demonstrate that AuNBP-LASEs can be effective as wound approximation devices for photothermal sealing.

Low-molecular-weight collagen peptides supplement promotes a healthy skin: A randomized, double-blinded, placebo-controlled study

BACKGROUND

Oral collagen peptides supplementation was reported to improve skin integrity and counteract skin aging.

AIMS

A randomized, double-blinded, placebo-controlled study was conducted to clinically evaluate the impact of low-molecular-weight collagen peptides on the human skin.

PATIENTS/METHODS

Healthy adult participants (n = 100) were randomly assigned to receive a test product containing low-molecular-weight collagen peptides or a placebo. Parameters of skin wrinkles, elasticity, hydration, and whitening (melanin and erythema indexes) were measured at baseline and after 4, 8, and 12 weeks.

RESULTS

Compared with the placebo group, the average skin roughness, maximum of all peak-to-valley values, maximum peak height of the wrinkle, and average maximum height of the wrinkle were significantly improved in the test group. Parameters of skin elasticity, including overall elasticity, net elasticity, and biological elasticity, were also significantly improved in the test group at Week 12 as compared with the placebo group. Moreover, skin hydration and whitening parameters changed more significantly in the test group than in the placebo group. None of the participants experienced adverse events related to the test product.

CONCLUSIONS

Taken together, these findings suggest that low-molecular-weight collagen peptides supplementation can safely ehance human skin wrinkling, hydration, elasticity, and whitening properties.

Low Molecular Weight Collagen Peptide (LMWCP) Promotes Hair Growth by Activating the Wnt/GSK-3β/β-Catenin Signaling Pathway

Low molecular weight collagen peptide (LMWCP) is a collagen hydrolysate derived from fish. We investigated the effects of LMWCP on hair growth using human dermal papilla cells (hDPCs), human hair follicles (hHFs), patch assay, and telogenic C57BL/6 mice, while also examining the underlying mechanisms of its action. LMWCP promoted proliferation and mitochondrial potential, and the secretion of hair growth-related factors, such as EGF, HB-EGF, FGF-4, and FGF-6 in hDPCs. Patch assay showed that LMWCP increased the neogeneration of new HFs in a dose-dependent manner. This result correlated with an increase in the expression of dermal papilla (DP) signature genes such as, ALPL, SHH, FGF7, and BMP-2. LMWCP upregulated phosphorylation of glycogen synthase kinase-3β (GSK-3β) and β-catenin, and nuclear translocation of β-catenin, and it increased the expression of Wnt3a, LEF1, VEGF, ALP, and β-catenin. LMWCP promoted the growth of hHFs and increased the expression of β-catenin and VEGF. Oral administration of LMWCP to mice significantly stimulated hair growth. The expression of Wnt3a, β-catenin, PCNA, Cyclin D1, and VEGF was also elevated in the back skin of the mice. Furthermore, LMWCP increased the expression of cytokeratin and Keratin Type I and II. Collectively, these findings demonstrate that LMWCP has the potential to increase hair growth via activating the Wnt/β-catenin signaling pathway.

Collagen study advances for photoaging skin

BACKGROUND

Collagen dominates the skin's extracellular matrix (ECM). Type I collagen comprises 80%-90% of the skin's collagen, followed by type III (8%-12%) and type V (5%). Reactive oxygen species, matrix metalloproteinases, and collagen degradation all increase during photoaging, which disrupts the ECM's dynamic balance and lowers the amount of total collagen in the body. In recent years, domestic and foreign researchers have conducted multidimensional and multifaceted studies on collagen and skin photoaging. Collagen and the peptides that are derivates of it are currently being used more and more in biomedicine and medical esthetics.

OBJECTIVE

Offering new suggestions for both the avoidance and remedy of photoaging.

METHODS

This article reviews collagen and its potential connection to skin photoaging, illustrates the effects of collagen and peptide supplementation derivatives on photoaged skin, and briefly describes other compounds that can also be used to fight photoaging by increasing collagen synthesis in the skin.

RESULT

Both internal and external aging are inevitable, and as the main component of extracellular matrix, collagen plays a variety of functions in maintaining skin structure and fighting skin aging, and its role in photoaging is undeniable. Ultraviolet radiation can induce increased fragmentation and degradation of cutaneous collagen, while conversely, supplementation with collagen can effectively counteract photodamage-induced skin impairment.

CONCLUSION

Collagen and its derived peptides are indispensable in photoaging skin, holding promising prospects for applications in skin aging.

The effect of oral supplements containing collagen peptides rich in X-Hyp or X-Hyp-Gly compared with normal collagen hydrolysates on skin elasticity and collagen holes: a randomised double-blind clinical study

Collagen peptides enriched with X-Hyp or X-Hyp-Gly have demonstrated resistance to digestive and systemic enzymes, suggesting their potential for improved absorption efficiency and enhancement of skin properties. This study aimed to evaluate the effects of oral supplementation with collagen peptides rich in X-Hyp or X-Hyp-Gly on skin properties in a clinical setting. A double-blind, randomized study was conducted on 30 healthy adult participants aged between 22 and 30. Normal collagen hydrolysates were used as the control, and each participant received a daily powdered drink containing either 5 grams of collagen peptides or hydrolysates (n = 15 in each group) for a period of 42 days. Skin elasticity was evaluated using the Cutometer, revealing a significant increase in the intervention group's skin elasticity (R2 values: 0.86 to 0.92, P < 0.001; R7 values: 0.77 to 0.84, P < 0.001). Collagen synthesis in the dermis was assessed using the SIAscope, demonstrating a substantial increase of 30.67 in the intervention group, while the control group exhibited a marginal increase of 0.49. In vitro digestion and cellular transport models were employed to evaluate the absorption and transport of Hyp-containing collagen peptides. LC-MS analysis demonstrated a significantly higher proportion of small peptide oligomers below 500 Da in the CP product compared to the control group (approximately 70% vs. 50%) after digestion. Additionally, the CP product exhibited a greater uptake of peptides (27%) compared to the control group (21%). These findings highlight the potential use of Hyp-containing collagen peptides with a low molecular weight in food supplements for improving skin health.

Nacre Extract from Pearl Oyster Shell Prevents D-Galactose-Induced Brain and Skin Aging

Pearl oyster shells comprise two layers, a prismatic and nacreous layer, of calcium carbonate. The nacreous layer has been used in Chinese medicine since ancient times. In this study, we investigated the effects of the extract from the nacreous layer of pearl oysters (nacre extract) on D-galactose-induced brain and skin aging. Treatment with nacre extract led to the recovery of D-galactose-induced memory impairment, as examined using the Barnes maze, novel object recognition, and Y-maze tests. A histological study showed that nacre extract suppressed D-galactose-induced neuronal cell death and the expression of B cell lymphoma 2 (Bcl-2)-associated X protein (Bax), which causes apoptosis in the hippocampus. In addition, the expression levels of brain-derived neurotrophic factor, which counteracts age-related brain dysfunction, and nicotinamide adenine dinucleotide-dependent deacetylase (sirtuin 1), which delays aging and extends lifespan, increased after nacre extract treatment. Moreover, the nacre extract showed anti-aging effects against D-galactose-induced skin aging; it suppressed D-galactose-induced wrinkle formation, decreased skin moisture, decreased epidermal thickness, and destroyed collagen arrangement associated with aging. Furthermore, the nacre extract suppressed oxidative stress associated with aging in the brain and skin by upregulating the expression of catalase and superoxide dismutase. The expression level of the cellular senescence marker p16, which is induced by oxidative stress, was elevated in the hippocampus and skin epidermal layer of D-galactose-treated mice, and it was suppressed by the administration of nacre extract. These results show that the nacre extract can suppress D-galactose-induced aging by enhancing anti-oxidant activity and suppressing p16 expression. Thus, the nacre extract may be an effective anti-aging agent.

Collagen supplementation in skin and orthopedic diseases: A review of the literature

Collagen is one of the main components of the extracellular matrix of the dermis and articular cartilage and influences the body's mechanical, organizational, and tissue formation properties. Produced from food industry by-products, it is considered a nutraceutical product widely used as an ingredient or supplement in food, pharmaceutical, and cosmetic industries. This study aimed to conduct a literature review on the scientific evidence regarding the beneficial effects of collagen consumption in the treatment of skin and orthopedic diseases. Literature data have shown that hydrolyzed collagen supplementation promotes skin changes, such as decreased wrinkle formation; increased skin elasticity; increased hydration; increased collagen content, density, and synthesis, which are factors closely associated with aging-related skin damage. Regarding orthopedic changes, collagen supplementation increases bone strength, density, and mass; improves joint stiffness/mobility, and functionality; and reduces pain. These aspects are associated with bone loss due to aging and damage caused by strenuous physical activity. Thus, this review addresses the economic and health potential of this source of amino acids and bioactive peptides extracted from food industry by-products.

Interactional, Functional and Biological Properties of Lactone Sophorolipid (LSL) and Collagen Oligopeptides (COP) in Aqueous Solution

For the mixed aqueous solution of LSL and COP, the interaction mode and mechanism have been comprehensively studied using multispectral methods including fluorescence spectrum, ultraviolet-visible adsorption spectrum (UV-Vis), and circular dichroism spectrum (CD). Then its surface activity, particle size, foaming, emulsifying, viscosity, and antibacterial properties are evaluated in detail by surface tension measurement (ST), dynamic light scattering (DLS), oscillametric method, spectrophotometer, ubbelohde viscometer and zone of inhibition separately. Compared with the single LSL or COP aqueous solution, the mixed system shows different performance optimizations in different aspects. The surface activity and foaming properties are mainly attributed to LSL, and the viscosity is attributed to COP. Fluorescence spectroscopy results show that the fluorescence distribution of COP has significant changes by the LSL addition and a static quenching mechanism is proved. The results of UV-Vis and CD spectra also show the changing conformation of COP by the LSL addition. The data of thermodynamic parameters prove that the combination of LSL and COP is a spontaneous exothermic process and is an enthalpy-driven process. The interaction mechanism between LSL and COP is very helpful for the application and development of the mixed mild biosurfactant-protein system used in the cosmetic and food industries.

Effects of Collagen Hydrolysate From Large Hybrid Sturgeon on Mitigating Ultraviolet B-Induced Photodamage

Ultraviolet B (UVB) radiation leads to the excessive accumulation of reactive oxygen species (ROS), which subsequently promote inflammation, degradation of the extracellular matrix, and photoaging in skin. Thus antioxidant activity is particularly important when screening for active substances to prevent or repair photodamage. Marine fish-derived bioactive peptides have become a trend in cosmetics and functional food industries owing to their potential dermatological benefits. In this study, 1-diphenyl- 2-pycryl-hydrazyl (DPPH) scavenging activity was selected to optimize the hydrolysis conditions of sturgeon skin collagen peptides with antioxidant activity. The optimal hydrolysis conditions for sturgeon skin collagen hydrolysate (SSCH) were determined by response surface methodology, which comprised an enzyme dosage of flavorzyme at 6,068.4 U/g, temperature of 35.5°C, pH of 7, and hydrolysis time of 6 h. SSCH showed good radical-scavenging capacities with a DPPH scavenging efficiency of 95%. Then, the effect of low-molecular-weight SSCH fraction (SSCH-L) on UVB irradiation-induced photodamage was evaluated in mouse fibroblast L929 cells and zebrafish. SSCH-L reduced intracellular ROS levels and the malondialdehyde content, thereby alleviating the oxidative damage caused by UVB radiation. Moreover SSCH-L inhibited the mRNA expression of genes encoding the pro-inflammatory cytokines IL-1β, IL-6, TNF-α, and Cox-2. SSCH-L treatment further increased the collagen Ⅰα1 content and had a significant inhibitory effect on matrix metalloproteinase expression. The phosphorylation level of JNK and the expression of c-Jun protein were significantly reduced by SSCH-L. Additionally, SSCH-L increased the tail fin area at 0.125 and 0.25 mg/ml in a zebrafish UVB radiation model, which highlighted the potential of SSCH-L to repair UVB-irradiated zebrafish skin damage. Peptide sequences of SSCH-L were identified by liquid chromatography-tandem mass spectrometry. Based on the 3D-QSAR modeling prediction, six total peptides were selected to test the UVB-protective activity. Among these peptides, DPFRHY showed good UVB-repair activity, ROS-scavenging activity, DNA damage-protective activity and apoptosis inhibition activity. These results suggested that DPFRHY has potential applications as a natural anti-photodamage material in cosmetic and functional food industries.

Effect of boron element on photoaging in rats

BACKGROUND

The present study further assessed the effects of oral and topical applications of boron, which is known to have antiinflammatory and wound healing effects, on photoaging.

METHODS

A total of 49 eight-week-old female Wistar albino rats randomly divided into seven groups (control, shaved control, shaved+UVB, topical dermabor 2% (D2), and %5 (D5), systemic sodium perborate tetrahydrate (SPT) 2% (SPT2) and 4% (SPT4). To induce an experimental photoaging, the rats were exposed to UVB at an emission spectrum of 290-320 nm. Biochemical, molecular, skin, histological, and collagen content analyzes were made at the end of the study.

RESULTS

Increased skin inflammatory parameters (COX-2, IL-8, NF-KB, IL-6, and TNF-α) levels in UVB-exposed groups were inhibited in all treatment groups. The tissue level of hydroxyproline and elastase was found to decrease in all UVB-exposed group. The level of hydroxyproline was significantly higher in the D2 and D5 groups than in the SPT2 and SPT4 groups. The level of elastase was significantly lower in the D2 and D5 groups than in the SPT2 and SPT4 groups.

CONCLUSIONS

In future, boron may be developed as a functionally protective treatment against photoaging caused by UVB, and may be included in sun protection systems.

Dual Skin-Whitening and Anti-wrinkle Function of Low-Molecular-Weight Fish Collagen

In this study, we investigated the protective effects of low-molecular-weight fish collagen from tilapia against melanogenesis in melanocytes, ultraviolet B (UVB)-irradiated Hs27 skin fibroblasts, and hairless mice. We observed collagen production-related pathways in UVB-irradiated Hs27 skin fibroblasts and hairless mice, and the melanogenesis-related pathways in melanocyte and UVB-irradiated hairless mice. The collagen production-related pathways were activated in the UVB-irradiated Hs27 skin fibroblasts and hairless mice. In addition, UVB exposure stimulated the melanogenesis-related pathways in melanocytes and hairless mice. However, treatment with low-molecular-weight fish collagen significantly increased the messenger RNA expressions of collagen production-related factors and significantly decreased the production of cytokines. Furthermore, treatment with low-molecular-weight fish collagen suppressed melanogenesis by inhibiting glutathione synthesis and downregulating melanocyte-inducing transcription factor expression through the suppression of cyclic AMP/protein kinase A/cAMP-responsive binding protein signaling and nitric oxide production. Low-molecular-weight fish collagen exerts protective effects against UVB-induced photoaging, through anti-inflammatory, antioxidant, and anti-melanogenesis activities and could be used for developing effective natural anti-photoaging products.

GT Collagen Improves Skin Moisturization in UVB-Irradiated HaCaT Cells and SKH-I Hairless Mice

We investigated the effects of GT collagen (Geltech low-molecular-weight fish collagen, FC) on skin moisturization in ultraviolet B (UVB)-irradiated HaCaT cells and SKH-I hairless mice. In vitro, we measured the expression of mRNA genes and proteins related to the skin moisturizing mechanism, hyaluronic acid concentrations, and sphingomyelin concentrations. As a result, FC increased the expression of LCB1, DEGS1, elastin, UGTrel7, and GlcNAc mRNA in UVB-irradiated HaCaT cells. Also, hyaluronic acid level, sphingomyelin level, and protein expressions of hyaluronan synthase (HAS)2 and CerS4 were increased compared to those in the UVB-irradiated control group. In vivo, we measured skin hydration through the expression of mRNA genes and proteins related to the skin moisturizing mechanism and found that the protein expression of HAS2 and CerS4 was increased in the groups taking FC. Moreover, FC intake increased the expression of LCB1, DEGS1, fibrilin-1, UGTrel8, and GlcNAc mRNA in UVB-irradiated SKH-I hairless mice. These results suggest that FC can be utilized to develop products aimed at improving skin moisturization.

Nutrition and youthful skin

Nutrition and dietary supplements have been used to promote a youthful appearance for millennia. Despite high public demand for these products, evidence supporting their efficacy is limited and often inconsistent. We discuss the structural and functional changes that occur in the skin during the aging process. We also review evidence supporting the use of nutritional supplements commonly used to promote a youthful appearance, including essential fatty acids, coenzyme Q, collagen peptides, curcumin, polyphenols, flavonoids, probiotics, silymarin, and vitamins A, C, D, and E. We also consider the role of advanced glycosylated end products, antiinflammatory diets, and caloric restriction in delaying premature skin aging. Although evidence supporting the use of some dietary interventions is promising, further long-term studies in humans are required to fully understand their effects on the promotion of a youthful appearance.

Low-Molecular-Weight Collagen Peptide Ameliorates Osteoarthritis Progression through Promoting Extracellular Matrix Synthesis by Chondrocytes in a Rabbit Anterior Cruciate Ligament Transection Model

This study examined whether the oral administration of low-molecular-weight collagen peptide (LMCP) containing 3% Gly-Pro-Hyp with >15% tripeptide (Gly-X-Y) content could ameliorate osteoarthritis (OA) progression using a rabbit anterior cruciate ligament transection (ACLT) model of induced OA and chondrocytes isolated from a patient with OA. Oral LMCP administration (100 or 200 mg/kg/day) for 12 weeks ameliorated cartilage damage and reduced the loss of proteoglycan compared to the findings in the ACLT control group, resulting in dose-dependent (p < 0.05) improvements of the OARSI score in hematoxylin & eosin (H&E) and Safranin O staining. In microcomputed tomography analysis, LMCP also significantly (p < 0.05) suppressed the deterioration of the microstructure in tibial subchondral bone during OA progression. The elevation of IL-1βand IL-6 concentrations in synovial fluid following OA induction was dose-dependently (p < 0.05) reduced by LMCP treatment. Furthermore, immunohistochemistry illustrated that LMCP significantly (p < 0.05) upregulated type II collagen and downregulated matrix metalloproteinase-13 in cartilage tissue. Consistent with the in vivo results, LMCP significantly (p < 0.05) increased the mRNA expression of COL2A1 and ACAN in chondrocytes isolated from a patient with OA regardless of the conditions for IL-1βinduction. These findings suggest that LMCP has potential as a therapeutic treatment for OA that stimulates cartilage regeneration.

Protective Effects of Collagen Tripeptides in Human Aortic Endothelial Cells by Restoring ROS-Induced Transcriptional Repression

Collagen tripeptide (CTP) is defined as a functional food material derived from collagenase digests of type I collagen and contains a high concentration of tripeptides with a Gly-X-Y sequence. CTP has several biological effects, including the acceleration of fracture healing, ameliorating osteoarthritis, and improving dryness and photoaging of the skin. Recently, an antiatherosclerotic effect of CTP has been reported, although its molecular mechanism is yet to be determined. In this study, we examined the effects of CTP on primary cultured human aortic endothelial cells (HAECs) under oxidative stress, because oxidative endothelial dysfunction is a trigger of atherosclerosis. DNA microarray and RT-qPCR analyses showed that CTP treatment recovered the downregulated expression of several genes, including the interleukin-3 receptor subunit alpha (IL3RA), which were suppressed by reactive oxygen species (ROS) treatment in HAECs. Furthermore, IL3RA knockdown significantly decreased the viability of HAECs compared with control cells. RT-qPCR analysis also showed that solute carrier 15 family peptide transporters, which are involved in CTP absorption into cells, were expressed in HAECs at levels more than comparable to those of a CTP-responsive human osteoblastic cell line. These results indicated that CTP exerts a protective effect for HAECs, at least in part, by regulating the recovery of ROS-induced transcriptional repression.

The Protective Effects of a Combination of an Arginine Silicate Complex and Magnesium Biotinate Against UV-Induced Skin Damage in Rats

The purpose of this study was to observe the effects of a novel combination of inositol-stabilized arginine silicate complex (ASI) and magnesium biotinate (MgB) on the prevention of skin damage after UVB exposure in rats. Forty-nine Sprague-Dawley rats were randomized into one of the following groups: (1) NC, normal control, (2) SC, shaved control, (3) UVB (exposed to UVB radiation), (4) ASI+MgB-L (Low Dose), (5) ASI+MgB-H (High Dose), (6) ASI+MgB-L+MgB cream, (7) ASI+MgB-H+MgB cream. The results showed that ASI+MgB treatment alleviated the macroscopic and histopathological damages in the skin of rats caused by UVB exposure. Skin elasticity evaluation showed a similar trend. ASI+MgB increased serum Mg, Fe, Zn, Cu, Si, biotin, and arginine concentrations and skin hydroxyproline and biotinidase levels while decreasing skin elastase activity (p < 0.05) and malondialdehyde (MDA) concentration (p < 0.001). Moreover, ASI+MgB treatment increased skin levels of biotin-dependent carboxylases (ACC1, ACC2, PC, PCC, MCC) and decreased mammalian target of rapamycin (mTOR) pathways and matrix metalloproteinase protein levels by the regulation of the activator protein 1 (AP-1), and mitogen activated protein kinases (MAPKs) signaling pathways. In addition, ASI+MgB caused lower levels of inflammatory factors, including TNF-α, NFκB, IL-6, IL-8, and COX-2 in the skin samples (p < 0.05). The levels of Bax and caspase-3 were increased, while anti-apoptotic protein Bcl-2 was decreased by UVB exposure, which was reversed by ASI+MgB treatment. These results show that treatment with ASI and MgB protects against skin damage by improving skin appearance, elasticity, inflammation, apoptosis, and overall health.

Dietary Collagen Hydrolysates Ameliorate Furrowed and Parched Skin Caused by Photoaging in Hairless Mice

Collagen hydrolysates have been suggested as a favorable antiaging modality in skin photoaged by persistent exposure to ultraviolet radiation (UV). The current study evaluated the beneficial effect of collagen hydrolysates (fsCH) extracted from Pangasius hypophthalmus fish skin on wrinkle formation and moisture preservation in dorsal skin of hairless mice challenged with UV-B. Inter-comparative experiments were conducted for anti-photoaging among fsCH, retinoic acid (RA), N-acetyl-D-glucosamine (NAG), and glycine-proline-hydroxyproline (GPH). Treating human HaCaT keratinocytes with 100−200 μg/mL fsCH reciprocally ameliorated the expression of aquaporin 3 (AQP3) and CD44 deranged by UV-B. The UV-B-induced deep furrows and skin thickening were improved in parched dorsal skin of mice supplemented with 206–412 mg/kg fsCH as well as RA and GPH. The UV-B irradiation enhanced collagen fiber loss in the dorsal dermis, which was attenuated by fsCH through enhancing procollagen conversion to collagen. The matrix metalloproteinase expression by UV-B in dorsal skin was diminished by fsCH, similar to RA and GPH, via blockade of collagen degradation. Supplementing fsCH to UV-B-irradiated mice decreased transepidermal water loss in dorsal skin with reduced AQP3 level and restored keratinocyte expression of filaggrin. The expression of hyaluronic acid synthase 2 and hyaluronidase 1 by UV-B was remarkably ameliorated with increased production of hyaluronic acid by treating fsCH to photoaged mice. Taken together, fsCH attenuated photoaging typical of deep wrinkles, epidermal thickening, and skin water loss, like NAG, RA, or GPH, through inhibiting collagen destruction and epidermal barrier impairment.

Cutaneous and ocular rosacea: Common and specific physiopathogenic mechanisms and study models

Rosacea is a chronic inflammatory disease that affects the face skin. It is clinically classified into the following four subgroups depending on its location and severity: erythematotelangiectatic, papulopustular, phymatous, and ocular. Rosacea is a multifactorial disease triggered by favoring factors, the pathogenesis of which remains imperfectly understood. Recognized mechanisms include the innate immune system, with the implication of Toll-like receptors (TLRs) and cathelicidins; neurovascular deregulation involving vascular endothelial growth factor (VEGF), transient receptor potential (TRP) ion channels, and neuropeptides; and dysfunction of skin sebaceous glands and ocular meibomian glands. Microorganisms, genetic predisposition, corticosteroid treatment, and ultraviolet B (UVB) radiation are favoring factors. In this paper, we review the common and specific molecular mechanisms involved in the pathogenesis of cutaneous and ocular rosacea and discuss laboratory and clinical studies, as well as experimental models.

Ingestion of collagen hydrolysates alleviates skin chronological aging in an aged mouse model by increasing collagen synthesis

Although the use of collagen hydrolysates (CHs) as nutraceutical agents to protect skin against photoaging has been widely investigated, little is known about their effects on skin chronological aging and the underlying mechanism. Nutritional supplementation, such as collagen and related hydrolysates, might have beneficial effects on chronologically aged skin just as on photoaged skin. Hence, 13-month-old female Kunming mice ingested CHs for eight weeks to evaluate the effects of CHs on ameliorating skin chronological aging. CHs were enzymatically prepared using alcalase or collagenase, named ACH and CCH, respectively. The results showed that CHs or proline intake had no obvious effects on skin moisture and hyaluronic acid contents. However, ACHs significantly decreased skin laxity, increased collagen I content, normalized the ratio of collagen I/III and repaired dermal collagen fibers in a dose-dependent manner. At an identical dose, ACH showed an advantage over CCH or proline in significantly increasing collagen I content. Further study indicated that CHs mainly improved skin condition by activating the transforming growth factor β (TGF-β)/Smad signaling pathway to promote the synthesis of collagen I rather than inhibiting collagen I degradation by deregulating activator protein-1 (AP-1). The results indicated that CHs could benefit skin in both extrinsic and intrinsic aging as active dietary supplements.

Protective Effect of Spirulina-Derived C-Phycocyanin against Ultraviolet B-Induced Damage in HaCaT Cells

Background and objectives: Reactive oxygen species (ROS) overwhelm the antioxidant defense system, induce oxidative stress, and increase matrix metalloproteinase (MMP) expression, resulting in skin aging. Thus, preventing ultraviolet B (UVB)-induced skin damage can attenuate skin aging. Spirulina (a biomass of cyanobacteria, also called blue-green algae) is comprised of prokaryotes, whereas microalgae are eukaryotes and are rich in phycocyanin, a powerful antioxidant. Materials and Methods: Here, we investigated the photoprotective effects of spirulina-derived C-phycocyanin (C-PC) against UVB radiation using keratinocytes (HaCaT cells). Results: UVB radiation increased MMP-1 and MMP-9 expression but decreased involucrin, filaggrin, and loricrin expression. C-PC showed no toxicity at concentrations of 5–80 μg/mL in terms of HaCaT cell viability. UVB-irradiated HaCaT cells had a 50.8% survival rate, which increased to 80.3% with C-PC treatment. MMP expression increased with UVB treatment, whereas MMP-1 and MMP-9 concentrations decreased with C-PC treatment. UVB reduced involucrin, filaggrin, and loricrin expression in HaCaT cells, but 80 μg/mL C-PC increased their expression by >25%. In the UVB radiation group, dichlorofluorescin diacetate fluorescence intensity in HaCaT cells increased by 81.6% compared with that in the control group, whereas ROS production was reduced by 51.2% and 55.1% upon treatment with 40 and 80 μg/mL C-PC, respectively. Conclusions: C-PC might reduce or prevent skin aging by reducing UVB irradiation-induced skin wrinkles and free radicals.

Effect of the Oral Administration of Common Evening Primrose Sprout (Oenothera biennis L.) Extract on Skin Function Improvement in UVB-irradiated Hairless Mice

Most of the studies on common evening primrose (Oenothera biennis L.) are focused on its oils (isolated from seed, root, and stem tissues). We aimed to investigate the effect of the oral administration of OBS-E on the improvement of skin function in skin-damaged hairless mice exposed to excessive ultraviolet B (UVB) radiation owing to the preliminary in vitro findings regarding the antioxidant, anti-wrinkle, and skin moisturizing activities of OBS-E. OBS-E administration for 14 weeks did not significantly affect the body weight or clinical signs. Significant reductions were observed in wrinkle parameters (area, number, length, and depth, and metalloproteinase levels) in OBS-E-administered mice compared with those in UVB-irradiated control mice. OBS-E significantly increased skin elasticity and hyaluronic acid content, but it significantly decreased transepidermal water loss. Histomorphometrical analysis revealed that OBS-E significantly reduced the epidermal thickness, area of the collagen-occupied region, and number of microfolds and inflammatory and mast cells. These results demonstrate that OBS-E can effectively enhance skin functions in terms of ameliorating wrinkle formation, promoting skin-moisturization, enhancing skin barrier function, and inhibiting inflammatory reactions. The obtained results provide good starting point for the continuation in the process of developing new inner beauty products based on OBS-E.

Fish Waste: From Problem to Valuable Resource

Following the growth of the global population and the subsequent rapid increase in urbanization and industrialization, the fisheries and aquaculture production has seen a massive increase driven mainly by the development of fishing technologies. Accordingly, a remarkable increase in the amount of fish waste has been produced around the world; it has been estimated that about two-thirds of the total amount of fish is discarded as waste, creating huge economic and environmental concerns. For this reason, the disposal and recycling of these wastes has become a key issue to be resolved. With the growing attention of the circular economy, the exploitation of underused or discarded marine material can represent a sustainable strategy for the realization of a circular bioeconomy, with the production of materials with high added value. In this study, we underline the enormous role that fish waste can have in the socio-economic sector. This review presents the different compounds with high commercial value obtained by fish byproducts, including collagen, enzymes, and bioactive peptides, and lists their possible applications in different fields.

AcGly-Phe-Asn(OH) and AcGly-Phe-Asn(NH2) tripeptides selectively affect the proliferation rate of MDA-MB 231 and HuDe cells

There is increasing interest in the bioactivity of peptides carrying out antiproliferative, antihypertensive, antimicrobial, antioxidant, anticholesterolemic, opioid, and antidiabetic activities. The bioavailability of peptides depends on how readily they are digested by endopeptidases and their ability to pass through cell membranes, features that are determined by the peptide's chemical and physical structure. On the basis of structures present in peptides that have biological activity, particularly antiproliferative activity, the tripeptides AcGly-Phe-Asn(OH) and AcGly-Phe-Asn(NH₂) have been designed and synthesized, then tested for their antiproliferative activity on human breast adenocarcinoma cells (MDA-MB 231) and human dermal fibroblasts (HuDe). The results show that the peptides significantly affect the proliferation of MDA-MB 231 and HuDe cells, with differentiated response between tumor and normal cells, and thus indicate that C-terminal amidation plays a role. Interestingly, the activity of both peptides in dermal fibroblasts follows the characteristic biphasic pattern of hormesis, a dose-response relationship.

Skin Hydration Effects of Scale-Up Fermented Cyclopia intermedia against Ultraviolet B-Induced Damage in Keratinocyte Cells and Hairless Mice

Photoaging occurs by chronic skin exposure to the sun and ultraviolet irradiation and leads to skin aging accompanied by a lack of skin hydration. We previously demonstrated the photoprotective effect of fermented Cyclopia intermedia (honeybush) extract on the skin. In this study, we evaluated the skin hydration effects of scaled-up fermented honeybush extract (HU-018) against ultraviolet B (UVB) radiation in HaCaT immortalized human keratinocytes and hairless mice. Pretreating HaCaT cells with HU-018 attenuated the decreased hyaluronic acid (HA) levels and mRNA expression of genes encoding involucrin, filaggrin, and loricrin by UVB irradiation. HU-018 treatment also ameliorated the decreased stratum corneum (SC) hydration and the increased levels of transepidermal water loss (TEWL) and erythema index (EI) in hairless mice after UVB exposure. Microarray analysis revealed changes in gene expression patterns of hyaluronan synthase 2 (Has2), transforming growth factor-beta 3 (TGF-β3), and elastin induced by HU-018 in UVB-irradiated mice. Consistently, the mRNA expression of Has2, TGF-β3, and elastin was increased by HU-018 treatment. Moreover, HU-018 restored the increased epidermal thickness and collagen disorganization in skin tissue of UVB-irradiated mice. HU-018 treatment also decreased matrix metalloproteinase-1 (MMP-1) expression and increased procollagen type-1, elastin, and TGF-β1 expression. In conclusion, we found that HU-018 promoted skin hydration processes in UVB-irradiated keratinocytes and hairless mice by modulating involucrin, filaggrin, loricrin, and HA expression and ameliorating visible signs of photoaging. Thus, HU-018 may be a good skin hydration agent for skin care.

The anti-skin-aging effect of oral administration of gelatin from the swim bladder of Amur sturgeon (Acipenser schrenckii)

Gelatin was extracted from the swim bladder of Amur sturgeon with hot water at 50 °C with acceptable yield (76.54%) and it showed type I collagen features. The degree of hydrolysis reached 70.42%, and 26.55% of collagen peptides (380.76 Da) survived, after simulating digestion, absorption and peripheral blood circulation in vitro. In situ single-pass intestinal perfusion showed that the AMW of the collagen peptides was about 1100 Da in the intestine and they were mainly absorbed in the jejunum (61.11%). A 12-month feeding experiment using rats demonstrated that gelatin improved the histological structure, increased the thickness of the dermis (18.45%) and the density of collagen fibers (22.17%), and decreased the ratio of type III to type I collagen (43.44%) of chronologically aged skin at 3.85 g per kg bw per d. Moreover, the antioxidant enzyme activities in skin were significantly enhanced, while the malondialdehyde content was reduced by 31.99%. These results provided new insights into the development of new nutraceuticals and functional foods for the anti-skin-aging effect.

Penta-1,2,3,4,6-O-Galloyl-β-D-Glucose Inhibits UVB-Induced Photoaging by Targeting PAK1 and JNK1

Penta-O-galloyl-β-D-glucose (PGG) is a gallotannin polyphenolic compound that occurs naturally in fermented Rhus verniciflua. The present study aimed to examine the effect of PGG on UVB-induced skin aging and its molecular mechanisms in HaCaT human keratinocytes and SKH-1 hairless mice models. PGG suppressed UVB-induced matrix metalloproteinase-1 (MMP-1) expression in HaCaT cells by inhibiting phosphorylation of RAF/MEK/ERK, MKK3/6/p38, and c-Jun. UVB-induced ERK and p38 signaling pathways that induce the MMP-1 expression were mediated by PAK1 in HaCaT cells. PGG suppressed PAK1 and JNK1 kinase activities, and directly bound both PAK1 in an ATP-competitive manner and JNK1 in an ATP-noncompetitive manner. Consistently, PGG decreased UVB-induced wrinkle formation, epidermal thickness, type 1 collagen and MMP-13 expression in mouse skin. Overall, these results indicate that PGG exhibits anti-photoaging effects in vitro and in vivo by the suppression of PAK1 and JNK1 kinase activities, and may be useful for the prevention of skin aging.

Hydrangea serrata (Thunb.) Ser. Extract Attenuate UVB-Induced Photoaging through MAPK/AP-1 Inactivation in Human Skin Fibroblasts and Hairless Mice

Skin photoaging is mainly caused by exposure to ultraviolet (UV) light, which increases expressions of matrix metalloproteinases (MMPs) and destroys collagen fibers, consequently inducing wrinkle formation. Nutritional factors have received scientific attention for use as agents for normal skin functions. The aim of this study was to investigate the effect of hot water extracts from the leaves of Hydrangea serrata (Thunb.) Ser. (WHS) against ultraviolet B (UVB)-induced skin photoaging and to elucidate the underlying molecular mechanisms in human foreskin fibroblasts (Hs68) and HR-1 hairless mice. WHS recovered UVB-reduced cell viability and ameliorated oxidative stress by inhibiting intracellular reactive oxygen species (ROS) generation in Hs68 cells. WHS rescued UVB-induced collagen degradation by suppressing MMP expression, and reduced the mRNA levels of inflammatory cytokines. These anti-photoaging activities of WHS were associated with inhibition of the activator protein 1 (AP-1), signal transduction and activation of transcription 1 (STAT1), and mitogen-activated protein kinase (MAPK) signaling pathways. Oral administration of WHS effectively alleviated dorsal skin from wrinkle formation, epidermal thickening, collagen degradation, and skin dehydration in HR-1 hairless mice exposed to UVB. Notably, WHS suppressed UVB activation of the AP-1 and MAPK signaling pathways in dorsal mouse skin tissues. Taken together, our data indicate that WHS prevents UVB-induced skin damage due to collagen degradation and MMP activation via inactivation of MAPK/AP-1 signaling pathway.

Orally administered collagen peptide protects against UVB-induced skin aging through the absorption of dipeptide forms, Gly-Pro and Pro-Hyp

Collagen hydrolysate is a well-known nutritional supplement for the improvement of healthy skin. Here, collagen peptide NS (CPNS) from fish scale was prepared, and its physicochemical properties were investigated. Gly-Pro was revealed as a representative low molecular weight peptide of CPNS, by performing prep-HPLC and LC-MS/MS. CPNS treatment attenuated matrix metalloproteinase-1 production and increased the synthesis of type 1 procollagen in HDF cells. After orally administering CPNS to rats, the plasma concentrations of Gly-Pro and Pro-Hyp increased dramatically. To examine the protective effects of CPNS against ultraviolet B (UVB)-induced photoaging in vivo, the dorsal skins of hairless mice were exposed to UVB and supplemented with CPNS for 12 weeks. The CPNS consumption significantly attenuated UVB-induced wrinkle formation, transepidermal water loss, and epidermis thickness, and increased skin hydration. Collectively, these results suggest that bioactive peptides of CPNS, Gly-Pro and Pro-Hyp, exert beneficial effects on skin health.

Anti-melanogenic effects of oyster hydrolysate in UVB-irradiated C57BL/6J mice and B16F10 melanoma cells via downregulation of cAMP signaling pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Pacific oyster (Crassostrea gigas) has been used to treat pigmentary disorders such as freckles, melasma, and moles in Korea.

AIM OF THE STUDY

We aimed to investigate the inhibitory effects of oyster hydrolysate (OH) on melanogenesis in B16F10 melanoma cells and UVB-irradiated C57BL/6J mice.

MATERIAL AND METHODS

The molecular weight distribution and peptide sequences of OH were detected using MALDI-TOF and UHPLC. To evaluate the anti-melanogenic effects of OH, cell viability, melanin content, tyrosinase activity, intracellular cyclic adenosine monophosphate (cAMP) and protein expressions levels were measured in B16F10 cells. In addition, OH was orally administered to UVB-irradiated mice for 9 weeks. After sacrificing the mice, the whitening effects of OH were evaluated based on histological observations and protein expression levels.

RESULTS

In B16F10 cells, OH decreased melanin content and tyrosinase activity in a dose-dependent manner. OH exhibited anti-melanogenic activities via downregulation of cAMP signaling pathway, which consequently decreased melanin synthesis. In UVB-irradiated mice groups, OH decreased the number of active melanocytes and melanin granules. The expression of tyrosinase-related proteins and microphthalmia-associated transcription factor (MITF) decreased in the OH-administered groups.

CONCLUSIONS

These results show that OH inhibits melanin synthesis in B16F10 cells via downregulation of cAMP signaling pathway and in UVB-irradiated mice, by decreasing the number of active melanocytes and melanin granules.

The collagen-derived compound collagen tripeptide induces collagen expression and extends lifespan via a conserved p38 mitogen-activated protein kinase cascade

The skin consists mostly of extracellular matrix (ECM) composed mainly of collagen, which provides a protective barrier from the environment. The skin continuously experiences harmful stress and damage. As aging progresses, the expression of various genes declines, and physiological functional deterioration occurs. The reduction of collagen accompanying aging impairs the barrier function of the skin and weakens protection from stressors. In the nematode Caenorhabditis elegans, ECM proteins turn over during aging. Older worms of longevity mutants exhibit increased collagen expression, whereas knockdown of collagen genes shortens lifespan. However, it is unclear whether the progression of aging can be delayed by increasing collagen production via an external stimulus. In this study, we examined the effects of collagen tripeptide (CTP), a collagen-derived compound, on lifespan and aging. Our results showed that CTP upregulated collagen genes via the p38 mitogen-activated protein kinase (MAPK)/SKN-1 pathway. Moreover, CTP extended lifespan and delayed aging through p38 MAPK/SKN-1 pathway. In addition, CTP also induced collagen expression via the p38 MAPK pathway in mammals. Our findings supported that external stimuli such as CTP could promote ECM youthfulness using a conserved signaling pathway, thereby contributing to suppression of aging.

Skin Moisturizing and Antiphotodamage Effects of Tyndallized Lactobacillus acidophilus IDCC 3302

Photoaging is generally the result of chronic exposure to the sun and ultraviolet (UV) radiation, which causes skin damage. In this study, we developed a UVB-induced hairless mouse model to determine whether Lactobacillus acidophilus IDCC 3302 tyndallizate (ACT3302) can enhance photodamaged skin repair. Mice (6 weeks old) were divided into six groups containing normal, UVB-treated vehicle, and UVB-treated ACT3302 (1 × 10⁵, 1 × 10⁶, 1 × 10⁷, and 1 × 10⁸ cells). Epidermal thickness was increased by UVB, but the thickening was lessened by ACT3302 as was the transepidermal water loss (TEWL). However, ACT3302 increased capacitance and decreased TEWL. Skin tissue staining to evaluate skin collagen increases in the number of skin collagen bundles in UVB-treated ACT3302 mice. UVB irradiation increased matrix metalloproteinase (MMP) and proinflammatory cytokine expression and activated mitogen-activated protein kinases in hairless mice; these changes were also attenuated by ACT3302. We conclude that ACT3302 effectively suppressed wrinkle formation induced by UVB irradiation through MMP downregulation. Therefore, ACT3302 potentially prevents skin photoaging and wrinkle formation.

Oral Intake of Low-Molecular-Weight Collagen Peptide Improves Hydration, Elasticity, and Wrinkling in Human Skin: A Randomized, Double-Blind, Placebo-Controlled Study

Collagen-peptide supplementation could be an effective remedy to improve hydration, elasticity, and wrinkling in human skin. The aim of this study was to conduct a double-blind, randomized, placebo-controlled trial to clinically evaluate the effect on human skin hydration, wrinkling, and elasticity of Low-molecular-weight Collagen peptide (LMWCP) with a tripetide (Gly-X-Y) content >15% including 3% Gly-Pro-Hyp. Individuals (n = 64) were randomly assigned to receive either placebo or 1000 mg of LMWCP once daily for 12 weeks. Parameters of skin hydration, wrinkling, and elasticity were assessed at baseline and after 6 weeks and 12 weeks. Compared with the placebo group, skin-hydration values were significantly higher in the LMWCP group after 6 weeks and 12 weeks. After 12 weeks in the LMWCP group, visual assessment score and three parameters of skin wrinkling were significantly improved compared with the placebo group. In case of skin elasticity, one parameter out of three was significantly improved in the LMWCP group from the baseline after 12 weeks, while, compared with the placebo group, two parameters out of three in the LMWCP group were higher with significance after 12 weeks. In terms of the safety of LMWCP, none of the subjects presented adverse symptoms related to the test material during the study period. These results suggest that LMWCP can be used as a health functional food ingredient to improve human skin hydration, elasticity, and wrinkling.