Protective Effect of Fucoxanthin against UVB-Induced Skin Photoaging in Hairless Mice

Phytocosmetic potential of Blumea balsamifera oil in mitigating UV-induced photoaging: Evidence from cellular and mouse models

ETHNOPHARMACOLOGICAL RELEVANCE

Blumea balsamifera (L.) DC. (BB), the source of Blumea balsamifera oil (BBO), is an aromatic medicinal plant, renowned for its pharmacological properties and its traditional use in Southeast Asian countries such as China, Thailand, Vietnam, Malaysia, and the Philippines for centuries. Traditionally, BB has been used as a raw herbal medicine for treating various skin conditions like eczema, dermatitis, athlete's foot, and wound healing for skin injuries.

AIM OF THE STUDY

This research aimed to explore the inhibitory effects of BBO on skin aging using two models: in vitro analysis with human dermal fibroblasts (HDF) under UVB-induced stress, and in vivo studies on UVA-induced dorsal skin aging in mice. The study sought to uncover the mechanisms behind BBO's anti-aging effects, specifically, its impact on cellular and tissue responses to UV-induced skin aging.

MATERIALS AND METHODS

We applied doses of 10-20 μL/mL of BBO to HDF cells that had been exposed to UVB radiation to simulate skin aging. We measured cell viability, and levels of reactive oxygen species (ROS), SA-β-gal, pro-inflammatory cytokines, and matrix metalloproteinases (MMPs). In addition, we investigated the involvement of mitogen-activated protein kinases (MAPKs) and nuclear factor kappa B (NF-κB) signaling pathways in mediating the anti-aging effects of BBO. Histopathological and biochemical analyses were conducted in a mouse model to examine the effects of BBO on UV-induced photoaging.

RESULTS

UV exposure accelerated aging, and caused cellular damage and inflammatory responses through ROS-mediated pathways. In HDF cells, BBO treatment countered the UVB-induced senescence, and the recovery of cell viability was correlated to notable reductions in SA-β-gal, ROS, pro-inflammatory cytokines, and MMPs. Mechanistically, the anti-aging effect of BBO was associated with the downregulation of the JNK/NF-κB signaling pathways. In the in vivo mouse model, BBO exhibited protective capabilities against UV-induced photoaging, which were manifested by the enhanced antioxidant enzyme activities and tissue remodeling.

CONCLUSIONS

BBO effectively protects fibroblasts from UV-induced photoaging through the JNK/NF-κB pathway. Recovery from photoaging involves an increase in dermal fibroblasts, alleviation of inflammation, accelerated synthesis of antioxidant enzymes, and slowed degradation of ECM proteins. Overall, BBO enhances the skin's defensive capabilities against oxidative stress, underscoring its potential as a therapeutic agent for oxidative stress-related skin aging.

Human Serum Albumin/Selenium Complex Nanoparticles Protect the Skin from Photoaging Injury

Introduction

Photoaging-induced skin damage leads to appearance issues and dermatoma. Selenium nanoparticles (SeNPs) possess high antioxidant properties but are prone to inactivation. In this study, human serum albumin/SeNPs (HSA-SeNPs) were synthesized for enhanced stability.

Methods

HSA-SeNPs were prepared by self-assembling denatured human serum albumin and inorganic selenite. The cytotoxicity of HSA-SeNPs was assessed using the MTT method. Cell survival and proliferation rates were tested to observe the protective effect of HSA-SeNPs on human skin keratinocytes against photoaging. Simultaneously, ICR mice were used for animal experiments. H&E and Masson trichromatic staining were employed to observe morphological changes in skin structure and collagen fiber disorders after UVB irradiation. Quantitative RT-PCR was utilized to measure changes in mRNA expression levels of factors related to collagen metabolism, inflammation, oxidative stress regulation, and senescence markers.

Results

The HSA-SeNPs group exhibited significantly higher survival and proliferation rates of UVB-irradiated keratinocytes than the control group. Following UVB irradiation, the back skin of ICR mice displayed severe sunburn with disrupted collagen fibers. However, HSA-SeNPs demonstrated superior efficacy in alleviating these symptoms compared to SeNPs alone. In a UVB-irradiated mice model, mRNA expression of collagen type I and III was dysregulated while MMP1, inflammatory factors, and p21 mRNA expression were upregulated; concurrently Nrf2 and Gpx1 mRNA expression were downregulated. In contrast, HSA-SeNPs maintained the mRNA expression of those factors to be stable In addition, the level of SOD decreased, and MDA elevated significantly in the skin after UVB irradiation, but no significant differences in SOD and MDA levels between the HSA-SeNPs group with UVB irradiation and the UVB-free untreated group.

Discussion

HSA-SeNPs have more anti-photoaging effects on the skin than SeNPs, including the protective effects on skin cell proliferation, cell survival, and structure under photoaging conditions. HSA-SeNPs can be used to protect skin from photoaging and repair skin injury caused by UVB exposure.

Preventive effects of dietary fucoxanthin on ultraviolet A induced photoaging in hairless mice

BACKGROUND

Repeated exposure to ultraviolet A (UVA) irradiation, which can penetrate the epidermis and reach the dermis, is one of the major causes of skin photoaging. Photoaged skin is characterized clinically by generalized wrinkling, a dry and loose appearance, and seborrheic keratoses, along with skin barrier dysfunction. Fucoxanthin, a xanthophyll carotenoid with a specific allenic bond and 5,6-monoepoxide in its structure, has been found to serve various functions as a food supplement. In the present study, the protective effects of orally administered fucoxanthin at relatively low concentrations (0.001% and 0.01%) against UVA induced photoaging were evaluated in vivo using hairless mice.

RESULTS

Oral supplementation of 0.001% fucoxanthin was sufficient for its metabolites to accumulate in the skin, thereby inhibiting pathological changes induced by UVA irradiation, including impaired skin barrier function and accelerated wrinkle formation. Analysis of gene expression revealed that dietary fucoxanthin exerted antiphotoaging effects, possibly by modulating natural moisturizing factor (NMF) synthesis, desquamation, and ceramide composition in the epidermis, and by inhibiting the UVA induced degradation of collagen fibers and inflammation in the dermis.

CONCLUSION

Taken together, our data indicate the potential application of dietary fucoxanthin as a novel ingredient in nutricosmetics for skin care against photoaging. © 2024 Society of Chemical Industry.

Effect and mechanism of Tricholoma matsutake extract combined with bakuchiol and ergothioneine on UVB-induced skin aging

BACKGROUND

Aging is a physiological phenomenon in the process of life, and skin aging has a significant impact on human appearance. Therefore, the search for methods to delay skin aging is of great significance for improving the quality of human life.

MATERIALS AND METHODS

This study investigated the anti-photoaging effect of Tricholoma matsutake (T) extract composition combined with bakuchiol (B) and ergothioneine (E), and explored its potential mechanism through transcriptome, metabolomics, and network pharmacology.

RESULTS

57 main chemical components are identified from the ethanol extract of T. matsutake (T), including D-carnitine (24.55%), α,α-trehalose (15.56%), DL malic acid (8.99%), D-(-)-quinic acid (7.46%), erucamide (7.04%) and so on. After TBE treatment, inflammation of the mice dorsal skin is significantly minimized. Hematoxylin and eosin (H&E) staining and toluidine blue staining reveal that TBE has an anti-inflammatory effect on the back skin tissue of mice. Masson staining shows that TBE has a repair effect on mice dorsal skin tissue. In addition, the inflammatory factors (IL-1β, IL-6, TNF-α) in the mice dorsal skin tissues are significantly reduced but collagen (COL-1) is significantly increased. By cellular immunofluorescence assay, TBE is shown to promote PPAR-α expression in cells. Transcriptomics, metabolomics, and network pharmacology have revealed that TBE can regulate exogenous stimuli and cancer-related signaling pathways to prevent skin aging.

CONCLUSION

The results suggest that TBE can be a beneficial supplement to natural anti-aging.

Oleracone C from Portulaca oleracea attenuates UVB-induced changes in matrix metalloproteinase and type I procollagen production via MAPK and TGF-β/Smad pathways in human keratinocytes

BACKGROUND

Chronic exposure to ultraviolet (UV) radiation induces photo-oxidation, which in turn causes the overproduction of matrix metalloproteinases (MMPs) and collagen degradation. These symptoms are referred to as photoaging, which is characterized by skin thickness, irregular pigmentation, elastosis and coarse wrinkles. In this study, the protective effects of oleracone C isolated from Portulaca olerace against UVB-induced changes in MMPs and type I procollagen production were investigated in human keratinocytes.

METHODS

Human immortalized keratinocytes have been used as an in vitro cell model to study the abnormal skin barrier development such as in photoaging. The effects of the compound on cell viability were determined by colorimetric MTT assay. This study also measured ROS production using DCFH-DA assay. Releases of MMPs and type Iα1 procollagen were analysed by ELISA. RT-PCR and Western blot were carried out to test the expressions of mRNA and proteins related to MMPs and type I procollagen biosynthesis.

RESULT

Effect of oleracone C against UVB-mediated oxidative stress was evaluated measuring its ability to eliminate UVB-induced activation of reactive oxygen species (ROS). Treatment of oleracone C hindered the production of intracellular ROS. UVB exposure increased MMPs (MMP-1, MMP-2 and MMP-9) release from keratinocytes and decreased the release of type I procollagen. Treatment with oleracone C reversed these effects of UVB exposure. Oleracone C treatment also diminished the intracellular expression of MMP-1, MMP-2 and MMP-9 and elevated the type I procollagen. Oleracone C suppressed the UVB irradiation-dependent upregulation phosphorylation of p38 and ERK1/2 in the mitogen-activated protein kinase (MAPK) pathway. Furthermore, oleracone C stimulated collagen production through the TGF-β signalling pathway, which activates collagen synthesis in UVB-irradiated keratinocytes.

CONCLUSION

These findings reasonably suggest ameliorating the potential of oleracone C against the UVB-induced photoaging of the human keratinocytes.

Advances in Fucoxanthin Research for the Prevention and Treatment of Inflammation-Related Diseases

Owing to its unique structure and properties, fucoxanthin (FX), a carotenoid, has attracted significant attention. There have been numerous studies that demonstrate FX's anti-inflammatory, antioxidant, antitumor, and anti-obesity properties against inflammation-related diseases. There is no consensus, however, regarding the molecular mechanisms underlying this phenomenon. In this review, we summarize the potential health benefits of FX in inflammatory-related diseases, from the perspective of animal and cellular experiments, to provide insights for future research on FX. Previous work in our lab has demonstrated that FX remarkably decreased LPS-induced inflammation and improved survival in septic mice. Further investigation of the activity of FX against a wide range of diseases will require new approaches to uncover its molecular mechanism. This review will provide an outline of the current state of knowledge regarding FX application in the clinical setting and suggest future directions to implement FX as a therapeutic ingredient in pharmaceutical sciences in order to develop it into a treatment strategy against inflammation-associated disorders.

Molecular mechanisms of Marine-Derived Natural Compounds as photoprotective strategies

Excessive exposure of the skin to ultraviolet radiation (UVR) causes oxidative stress, inflammation, immunosuppression, apoptosis, and changes in the extracellular matrix, which lead to the development of photoaging and photodamage of skin. At the molecular level, these pathological changes are mainly caused by the activation of related protein kinases and downstream transcription pathways, the increase of matrix metalloproteinase, the formation of reactive oxygen species, and the combined action of cytokines and inflammatory mediators. At present, the photostability, toxicity, and damage to marine ecosystems of most sun protection products in the market have affected their efficacy and safety. Another way is to use natural products produced by various marine species. Marine organisms have evolved a variety of molecular strategies to protect themselves from the harmful effects of ultraviolet radiation, and their unique chemicals have attracted more and more attention in the research of photoprotection and photoaging resistance. This article provides an extensive description of the recent literature on the potential of Marine-Derived Natural Compounds (MDNCs) as photoprotective and photoprotective agents. It reviews the positive effects of MDNCs in counteracting UV-induced oxidative stress, inflammation, DNA damage, apoptosis, immunosuppression, and extracellular matrix degradation. Some MDNCs have the potential to develop feasible solutions for related phenomena, such as photoaging and photodamage caused by UVR.

Fucoxanthin: A Promising Phytochemical on Diverse Pharmacological Targets

Fucoxanthin (FX) is a special carotenoid having an allenic bond in its structure. FX is extracted from a variety of algae and edible seaweeds. It has been proved to contain numerous health benefits and preventive effects against diseases like diabetes, obesity, liver cirrhosis, malignant cancer, etc. Thus, FX can be used as a potent source of both pharmacological and nutritional ingredient to prevent infectious diseases. In this review, we gathered the information regarding the current findings on antimicrobial, antioxidant, anti-inflammatory, skin protective, anti-obesity, antidiabetic, hepatoprotective, and other properties of FX including its bioavailability and stability characteristics. This review aims to assist further biochemical studies in order to develop further pharmaceutical assets and nutritional products in combination with FX and its various metabolites.

Shedding a New Light on Skin Aging, Iron- and Redox-Homeostasis and Emerging Natural Antioxidants

Reactive oxygen species (ROS) are necessary for normal cell signaling and the antimicrobial defense of the skin. However excess production of ROS can disrupt the cellular redox balance and overwhelm the cellular antioxidant (AO) capacity, leading to oxidative stress. In the skin, oxidative stress plays a key role in driving both extrinsic and intrinsic aging. Sunlight exposure has also been a major contributor to extrinsic photoaging of the skin as its oxidising components disrupt both redox- and iron-homeostasis, promoting oxidative damage to skin cells and tissue constituents. Upon oxidative insults, the interplay between excess accumulation of ROS and redox-active labile iron (LI) and its detrimental consequences to the skin are often overlooked. In this review we have revisited the oxidative mechanisms underlying skin damage and aging by focussing on the concerted action of ROS and redox-active LI in the initiation and progression of intrinsic and extrinsic skin aging processes. Based on these, we propose to redefine the selection criteria for skin antiaging and photoprotective ingredients to include natural antioxidants (AOs) exhibiting robust redox-balancing and/or iron-chelating properties. This would promote the concept of natural-based or bio-inspired bifunctional anti-aging and photoprotective ingredients for skincare and sunscreen formulations with both AO and iron-chelating properties.

Advances on marine-derived natural radioprotection compounds: historic development and future perspective

Natural extracts and compounds from marine resources have gained intensive scientific and industry attention for radioprotective activities in the past ten years. However, the marine-derived radioprotectants have been studied against UV-rays, gamma (γ)-rays and X-rays for more than 30 years. This review aims to identify key marine-derived extracts/compounds and their modes of action studied for radioprotective activities from 1986 to 2019. A comprehensive survey was conducted to establish the trend in terms of the publications each year and the countries of origin. A total of 40 extracts and 34 natural compounds showing radioprotective activities against UV-rays, gamma (γ)-rays and X-rays were identified from a range of marine plants and animals. These extracts and compounds are broadly categorized into polysaccharides, phlorotannins, carotenoids and mycosporine-like amino acids (MAAs). Macroalgae and microalgae were found to be the dominant sources of polysaccharides, phlorotannins and carotenoids. MAAs were mainly identified in algae, sponges, sea cucumber and corals that showed significant UV-absorbing activities. A number of radioprotective mechanisms were shown by these compounds, predominantly free radicals scavenging, inhibition of apoptosis, UV-ray absorption and DNA damage-repair signaling pathways. While these bio-discoveries warrant further investigation and development of radioprotective therapeutics, however, the lack of clinical studies is a major obstacle to be tackled in the future.

Supplementary Information

The online version contains supplementary material available at 10.1007/s42995-021-00095-x.

Role of Fucoxanthin towards Cadmium-induced renal impairment with the antioxidant and anti-lipid peroxide activities

Kidney damages caused by cadmium are considered to be one of the most dangerous consequences for the human body. This study aimed to investigate the protective effects of fucoxanthin supplementation on mice models subjected to cadmium-induced kidney damage. The mice treated with cadmium chloride (CdCl₂) were observed to have significantly reduced the cross-section area of glomeruli. Cadmium exposure has also caused the damage of the structural integrity of mitochondria and increased blood urea nitrogen (BUN), kidney injury molecule 1 (KIM1), and neutrophil gelatinase associated lipocalin (NGAL) levels. Peroxidase (POD), superoxide dismutase (SOD), catalase (CAT), and ascorbate peroxidase (APX) levels in cadmium-exposed mice were markedly declined. Caspase3, caspase8, and caspase9 gene expressions in association with apoptosis were dramatically elevated in renal tissues. The CdCl₂ treated mice were orally administered with 50 mg/kg Shenfukang, 10 mg/kg, 25 mg/kg, and 50 mg/kg fucoxanthin for 14 days. The results revealed that high doses of fucoxanthin administration significantly decreased BUN, KIM1, NGAL levels, increasing POD, SOD, CAT, and ascorbate APX levels. Fucoxanthin administration also promoted recovery of the renal functions, micro-structural organization, and ultra-structural organization in the renal cells. In summary, the ameliorative effects of fucoxanthin supplementation against cadmium-induced kidney damage were mediated via inhibiting oxidative stress and apoptosis, promoting the recovery of structural integrity of mitochondria.

Modulation of the ubiquitin-proteasome system by marine natural products

The ubiquitin-proteasome system (UPS) is a key player in the maintenance of cellular protein homeostasis (proteostasis). Since proteasome function declines upon aging leading to the acceleration of its progression and the manifestation of age-related pathologies, many attempts have been performed towards proteasome activation as a strategy to promote healthspan and longevity. The marine environment hosts a plethora of organisms that produce a vast array of primary and secondary metabolites, the majority of which are unique, exhibiting a wide spectrum of biological activities. The fact that these biologically important compounds are also present in edible marine organisms has sparked the interest for elucidating their potential health-related applications. In this review, we focus on the antioxidant, anti-aging, anti-aggregation and anti-photoaging properties of various marine constituents. We further discuss representatives of marine compounds classes with regard to their potential (direct or indirect) action on UPS components that could serve as UPS modulators and exert beneficial effects on conditions such as oxidative stress, aging and age-related diseases.

Anti-Photoaging and Potential Skin Health Benefits of Seaweeds

The skin health benefits of seaweeds have been known since time immemorial. They are known as potential renewable sources of bioactive metabolites that have unique structural and functional features compared to their terrestrial counterparts. In addition, to the consciousness of green, eco-friendly, and natural skincare and cosmetics products, their extracts and bioactive compounds such as fucoidan, laminarin, carrageenan, fucoxanthin, and mycosporine like amino acids (MAAs) have proven useful in the skincare and cosmetic industries. These bioactive compounds have shown potential anti-photoaging properties. Furthermore, some of these bioactive compounds have been clinically tested and currently available in the market. In this contribution, the recent studies on anti-photoaging properties of extracts and bioactive compounds derived from seaweeds were described and discussed.

Therapeutic attributes and applied aspects of biological macromolecules (polypeptides, fucoxanthin, sterols, fatty acids, polysaccharides, and polyphenols) from diatoms - A review

Diatoms are ubiquitous, biologically widespread, and have global significance due to their unique silica cell wall composition and noteworthy applied aspects. Diatoms are being extensively exploited for environmental monitoring, reconstruction, and stratigraphic correlation. However, considering all the rich elements of diatoms biology, the current literature lacks sufficient information on the therapeutic attributes and applied aspects of biological macromolecules from diatoms, hampering added advances in all aspects of diatom biology. Diatoms offer numerous high-value compounds, such as fatty acids, polysaccharides, polypeptides, pigments, and polyphenols. Diatoms with a high content of PUFA's are targets of transformation into high-value products through microalgal technologies due to their wide application and growing market as nutraceuticals and food supplements. Diatoms are renewable biomaterial, which can be used to develop drug delivery systems due to biocompatibility, surface area, cost-effective ratio, and ease in surface modifications. Innovative approaches are needed to envisage cost-effective ways for the isolation of bioactive compounds, enhance productivity, and elucidate the detailed mechanism of action. This review spotlights the notable applications of diatoms and their biologically active constituents, such as fucoxanthin and omega 3 fatty acids, among others with unique structural and functional entities.

Meeting Sustainable Development Goals: Alternative Extraction Processes for Fucoxanthin in Algae

The ever-expanding human population puts tremendous pressure on global food security. With climate change threats lowering crop productivity and food nutritional quality, it is important to search for alternative and sustainable food sources. Microalgae are a promising carbon-neutral biomass with fast growth rate and do not compete with terrestrial crops for land use. More so, microalgae synthesize exclusive marine carotenoids shown to not only exert antioxidant activities but also anti-cancer properties. Unfortunately, the conventional method for fucoxanthin extraction is mainly based on solvent extraction, which is cheap but less environmentally friendly. With the emergence of greener extraction techniques, the extraction of fucoxanthin could adopt these strategies aligned to UN Sustainable Development Goals (SDGs). This is a timely review with a focus on existing fucoxanthin extraction processes, complemented with future outlook on the potential and limitations in alternative fucoxanthin extraction technologies. This review will serve as an important guide to the sustainable and environmentally friendly extraction of fucoxanthin and other carotenoids including but not limited to astaxanthin, lutein or zeaxanthin. This is aligned to the SDGs wherein it is envisaged that this review becomes an antecedent to further research work in extract standardization with the goal of meeting quality control and quality assurance benchmarks for future commercialization purposes.

Process optimization of fucoxanthin production with Tisochrysis lutea

To optimize fucoxanthin production in Tisochrysis lutea, the effect of different process parameters on fucoxanthin productivity (Pfx) were evaluated using batch and continuous experiments. In batch, the highest Pfx was found at 30 °C and 300 μmol m^-2 s^-1, allowing to design continuous experiments to optimize the dilution rate. The highest ever reported Pfx (9.43-9.81 mg L^-1 d^-1) was achieved at dilution rates of 0.53 and 0.80 d^-1. Irradiance was varied (50-500 μmol m^-2 s^-1) to result in a range of absorbed light between 2.23 and 25.80 mol m^-2 d^-1 at a fixed dilution rate (0.53 d^-1). These experiments validated the hypothesis that light absorbed can be used to predict fucoxanthin content, resulting in 2.23 mol m^-2 d^-1 triggering the highest fucoxanthin content (16.39 mg/g). The highest Pfx was found with 18.38 mol m^-2 d^-1. These results can be used to achieve high Pfx or fucoxanthin content during cultivation of Tisochrysis lutea.

On a Beam of Light: Photoprotective Activities of the Marine Carotenoids Astaxanthin and Fucoxanthin in Suppression of Inflammation and Cancer

Every day, we come into contact with ultraviolet radiation (UVR). If under medical supervision, small amounts of UVR could be beneficial, the detrimental and hazardous effects of UVR exposure dictate an unbalance towards the risks on the risk-benefit ratio. Acute and chronic effects of ultraviolet-A and ultraviolet-B involve mainly the skin, the immune system, and the eyes. Photodamage is an umbrella term that includes general phototoxicity, photoaging, and cancer caused by UVR. All these phenomena are mediated by direct or indirect oxidative stress and inflammation and are strictly connected one to the other. Astaxanthin (ASX) and fucoxanthin (FX) are peculiar marine carotenoids characterized by outstanding antioxidant properties. In particular, ASX showed exceptional efficacy in counteracting all categories of photodamages, in vitro and in vivo, thanks to both antioxidant potential and activation of alternative pathways. Less evidence has been produced about FX, but it still represents an interesting promise to prevent the detrimental effect of UVR. Altogether, these results highlight the importance of digging into the marine ecosystem to look for new compounds that could be beneficial for human health and confirm that the marine environment is as much as full of active compounds as the terrestrial one, it just needs to be more explored.

Dietary ceramide 2-aminoethylphosphonate, a marine sphingophosphonolipid, improves skin barrier function in hairless mice

Sphingolipids are one of the major components of cell membranes and are ubiquitous in eukaryotic organisms. Ceramide 2-aminoethylphosphonate (CAEP) of marine origin is a unique and abundant sphingophosphonolipid with a C-P bond. Although molluscs such as squids and bivalves, containing CAEP, are consumed globally, the dietary efficacy of CAEP is not understood. We investigated the efficacy of marine sphingophosphonolipids by studying the effect of dietary CAEP on the improvement of the skin barrier function in hairless mice fed a diet that induces severely dry-skin condition. The disrupted skin barrier functions such as an increase in the transepidermal water loss (TEWL), a decrease in the skin hydration index, and epidermal hyperplasia were restored by CEAP dietary supplementation. Correspondingly, dietary CAEP significantly increased the content of covalently bound ω-hydroxyceramide, and the expression of its biosynthesis-related genes in the skin. These effects of dietary CAEP mimic those of dietary plant glucosylceramide. The novel observations from this study show an enhancement in the skin barrier function by dietary CAEP and the effects could be contributed by the upregulation of covalently bound ω-hydroxyceramide synthesis in the skin.

Algae Metabolites in Cosmeceutical: An Overview of Current Applications and Challenges

Cosmetics are widely used by people around the world to protect the skin from external stimuli. Consumer preference towards natural cosmetic products has increased as the synthetic cosmetic products caused adverse side effects and resulted in low absorption rate due to the chemicals' larger molecular size. The cosmetic industry uses the term "cosmeceutical", referring to a cosmetic product that is claimed to have medicinal or drug-like benefits. Marine algae have gained tremendous attention in cosmeceuticals. They are one of the richest marine resources considered safe and possessed negligible cytotoxicity effects on humans. Marine algae are rich in bioactive substances that have shown to exhibit strong benefits to the skin, particularly in overcoming rashes, pigmentation, aging, and cancer. The current review provides a detailed survey of the literature on cosmeceutical potentials and applications of algae as skin whitening, anti-aging, anticancer, antioxidant, anti-inflammation, and antimicrobial agents. The biological functions of algae and the underlying mechanisms of all these activities are included in this review. In addition, the challenges of using algae in cosmeceutical applications, such as the effectiveness of different extraction methods and processing, quality assurance, and regulations concerning extracts of algae in this sector were also discussed.

Fucoxanthin for Topical Administration, a Phototoxic vs. Photoprotective Potential in a Tiered Strategy Assessed by In Vitro Methods

Fucoxanthin possesses a well-described antioxidant activity that might be useful for human skin photoprotection. However, there is a lack of scientific information regarding its properties when applied onto human skin. Thus, the objective of the present study was to assess the photoprotective and phototoxicity potential of fucoxanthin based on its ultraviolet (UVB 280-320 nm; UVA 320-400 nm) and visible (VIS 400-700 nm) absorption, photostability, phototoxicity in 3T3 mouse fibroblast culture vs. full-thickness reconstructed human skin (RHS), and its ability to inhibit reactive oxygen species formation that is induced by UVA on HaCaT keratinocytes. Later, we evaluated the antioxidant properties of the sunscreen formulation plus 0.5% fucoxanthin onto RHS to confirm its bioavailability and antioxidant potential through the skin layers. The compound was isolated from the alga Desmarestia anceps. Fucoxanthin, despite presenting chemical photo-instability (dose 6 J/cm2: 35% UVA and 21% VIS absorbance reduction), showed acceptable photodegradation (dose 27.5 J/cm2: 5.8% UVB and 12.5% UVA absorbance reduction) when it was added to a sunscreen at 0.5% (w/v). In addition, it increased by 72% of the total sunscreen UV absorption spectra, presenting UV-booster properties. Fucoxanthin presented phototoxic potential in 3T3 fibroblasts (mean photo effect 0.917), but it was non-phototoxic in the RHS model due to barrier function that was provided by the stratum corneum. In addition, it showed a significant inhibition of ROS formation at 0.01% (p < 0.001), in HaCat, and in a sunscreen at 0.5% (w/v) (p < 0.001), in RHS. In conclusion, in vitro results showed fucoxanthin protective potential to the skin that might contribute to improving the photoprotective potential of sunscreens in vivo.

Treatment with Modified Extracts of the Microalga Planktochlorella nurekis Attenuates the Development of Stress-Induced Senescence in Human Skin Cells

More recently, we have proposed a safe non-vector approach to modifying the biochemical profiles of the microalga Planktochlorella nurekis and obtained twelve clones with improved content of lipids and selected pigments and B vitamins and antioxidant activity compared to unaffected cells. In the present study, the biological activity of water and ethanolic extracts of modified clones is investigated in the context of their applications in the cosmetic industry and regenerative medicine. Extract-mediated effects on cell cycle progression, proliferation, migration, mitogenic response, apoptosis induction, and oxidative and nitrosative stress promotion were analyzed in normal human fibroblasts and keratinocytes in vitro. Microalgal extracts did not promote cell proliferation and were relatively non-cytotoxic when short-term treatment was considered. Long-term stimulation with selected microalgal extracts attenuated the development of oxidative stress-induced senescence in skin cells that, at least in part, was correlated with nitric oxide signaling and increased niacin and biotin levels compared to an unmodified microalgal clone. We postulate that selected microalgal extracts of Planktochlorella nurekis can be considered to be used in skin anti-aging therapy.

Sunscreen Boosting Effect by Solid Lipid Nanoparticles-Loaded Fucoxanthin Formulation

Fucoxanthin is a bioactive compound that is a kind of natural carotenoid. Fucoxanthin is known to protect against UV-B-induced cell damage in hairless mice, even though it is physiochemically unstable to heat and acid due to its polyunsaturated structure, indicating that fucoxanthin possesses a low bioavailability, and this disadvantage limits its application in the cosmetic industry. Solid lipid nanoparticle (SLN) systems are known to be suitable as carriers for sunscreen agents. In this research work, the sunscreen-boosting effect of SLN, as a deliverer of functional ingredient, especially fucoxanthin, has been developed and evaluated by comparing the sunburn protection factors (SPF) of macroemulsion (cream and lotion type) and an SLN formula containing various kinds of sunscreen agents, respectively. Several results such as stability test, particle size, DSC analysis, and X-ray analysis show that the SLN formula loading fucoxanthin has the possibility of being a stable and high-functioning ingredient delivery system. Moreover, the SLN formula has shown a higher SPF value than others, meaning that the SLN formula exhibits a good sunscreen-boosting effect. This study indicates that the use of SLN as a carrier enhanced the bioavailability of fucoxanthin and shows that SLN could be a promising carrier for the production of sunscreen products by allowing the scaling-up of production.

Potential Use of Seaweed Bioactive Compounds in Skincare-A Review

Modern lifestyles have developed new attention on appearance and personal care which attract a huge number of consumers towards cosmetic products. The demand for a skincare product with natural ingredients is rapidly increasing. Seaweeds are major resources for in-demand active compounds with a wide variety of applications. The use of seaweed-derived ingredients in cosmetic products has increased in recent years as many scientific studies have proved the potential skincare properties of seaweed bioactive compounds. This review emphasizes possible skincare properties of seaweed bioactive compounds. The review outlines the mechanism involved in skin problems including hyperpigmentation, premature skin aging, and acne in the first part while the second part focuses on the promising application of seaweeds in skin protection by highlighting the bioactive compound responsible for their bioactivity.

Aquaculture and by-products: Challenges and opportunities in the use of alternative protein sources and bioactive compounds

There is a growing concern about chronic diseases such as obesity, diabetes, hypertension, hypercholesterolemia, cancer and cardiovascular diseases resulting from profound changes in the western lifestyle. Aquaculture by-products are generated in large quantities and they can be profitably recycled through their bioactive compounds used for health or food supplements. Improving waste utilization in the field of aquaculture is essential for a sustainable industry to prevent or minimize the environmental impact. In this sense fish by-products are a great source of protein and omega-3 polyunsaturated fatty acids which are particularly studied on Atlantic salmon or rainbow trout. Fish protein hydrolysate (FPH) obtained from chemical, enzymatical and microbial hydrolysis of processing by-products are being used as a source of amino acids and peptides with high digestibility, fast absorption and important biological activities. Omega-3 polyunsaturated fatty acids, eicosapentaenoic (EPA) and docosahexaenoic (DHA) from fish discards have been reported to decrease postprandial triacylglycerol levels, reduction of blood pressure, platelet aggregation and the inflammatory response. Crustacean by-products can also be used to produce chitosan with antioxidant and antimicrobial activity for food and pharmaceutical industries and carotenoids with important biological activity. Seaweeds are rich in bioactive compounds such as alginate, carrageenan, agar, carotenoids and polyphenols with different biological activities such as antioxidant, anticancer, antidiabetic, antimicrobial or anti-inflammatory activity. Finally, regarding harvest microalgae, during the past decades, they were mainly used in the healthy food market, with >75% of the annual microalgal biomass production, used for the manufacture of powders, tablets, capsules or pills. We will report and discuss the present and future role of aquaculture by-products as sources of biomolecules for the design and development of functional foods/beverages. This chapter will focus on the main bioactive compounds from aquaculture by-products as functional compounds in food and their applications in biomedicine for the prevention and treatment of diseases.

Fucoxanthin and Rosmarinic Acid Combination Has Anti-Inflammatory Effects through Regulation of NLRP3 Inflammasome in UVB-Exposed HaCaT Keratinocytes

Excessive exposure to ultraviolet (UV) radiation is the main risk factor to develop skin pathologies or cancer because it encourages oxidative condition and skin inflammation. In this sense, strategies for its prevention are currently being evaluated. Natural products such as carotenoids or polyphenols, which are abundant in the marine environment, have been used in the prevention of oxidative stress due to their demonstrated antioxidant activities. Nevertheless, the anti-inflammatory activity and its implication in photo-prevention have not been extensively studied. Thus, we aimed to evaluate the combination of fucoxanthin (FX) and rosmarinic acid (RA) on cell viability, apoptosis induction, inflammasome regulation, and anti-oxidative response activation in UVB-irradiated HaCaT keratinocytes. We demonstrated for the first time that the combination of FX and RA (5 µM RA plus 5 μM FX, designated as M2) improved antioxidant and anti-inflammatory profiles in comparison to compounds assayed individually, by reducing UVB-induced apoptosis and the consequent ROS production. Furthermore, the M2 combination modulated the inflammatory response through down-regulation of inflammasome components such as NLRP3, ASC, and Caspase-1, and the interleukin (IL)-1β production. In addition, Nrf2 and HO-1 antioxidant genes expression increased in UVB-exposed HaCaT cells pre-treated with M2. These results suggest that this combination of natural products exerts photo-protective effects by down-regulating NRLP3-inflammasome and increasing Nrf2 signalling pathway.

Do We Utilize Our Knowledge of the Skin Protective Effects of Carotenoids Enough?

Due to their potential health-promoting effects, carotenoids have drawn both scientific and public attention in recent years. The primary source of carotenoids in the human skin is diet, mainly fruits, vegetables, and marine product, but they may originate from supplementation and topical application, too. In the skin, they accumulate mostly in the epidermis and act as a protective barrier to various environmental influences. Namely, the skin is exposed to numerous environmental factors, including ultraviolet radiation (UVR), air pollution, and smoking, that cause oxidative stress within the skin with consequent premature (extrinsic) aging. UVR, as the most prominent environmental factor, may cause additional detrimental skin effects, such as sunburn, DNA damage, and skin cancer. Therefore, photoprotection is the first line intervention in the prevention of premature aging and skin cancer. Numerous studies have demonstrated that carotenoids, particularly β-carotene, lycopene, lutein, and astaxanthin, have photoprotective effects, not only through direct light-absorbing properties, but also through their antioxidant effects (scavenging reactive oxygen species), as well as by regulation of UV light-induced gene expression, modulation of stress-dependent signaling, and/or suppression of cellular and tissue responses like inflammation. Interventional studies in humans with carotenoid-rich diet have shown its photoprotective effects on the skin (mostly by decreasing the sensitivity to UVR-induced erythema) and its beneficial effects in prevention and improvement of skin aging (improved skin elasticity and hydration, skin texture, wrinkles, and age spots). Furthermore, carotenoids may be helpful in the prevention and treatment of some photodermatoses, including erythropoietic protoporphyria (EPP), porphyria cutanea tarda (PCT) and polymorphous light eruption (PMLE). Although UVR is recognized as the main etiopathogenetic factor in the development of non-melanoma skin cancer (NMSC) and melanoma, and the photoprotective effects of carotenoids are certain, available studies still could not undoubtedly confirm the protective role of carotenoids in skin photocarcinogenesis.

Grape Peel Extract and Resveratrol Inhibit Wrinkle Formation in Mice Model Through Activation of Nrf2/HO-1 Signaling Pathway

Considering the anti-photoaging effect of antioxidant compounds, we investigated the protective capacity of grape peel extract (GPE) and resveratrol on ultraviolet (UV)-induced skin wrinkle formation. Total phenolic, total anthocyanin, and total flavonoid content in GPE prepared from peel of Campbell Early variety were 23.96 ± 0.09, 3.27 ± 0.40, and 1.24 ± 0.09 mg/g dry weight, respectively. Additionally, trans-resveratrol and piceid content of the resulting GPE were 117.14 ± 19.97 and 85.23 ± 8.89 µg/g dry weight, respectively. Oral administration of either 2 g GPE or 2 mg resveratrol per kg body weight in mice attenuated UVB-induced epidermal thickening (the thickness was reduced by about 63% and 55% with GPE and resveratrol consumption prior to exposure to UVB, respectively, compared to only UVB-treated condition) and had marginally protective effect on wrinkle formation of skin exposed to UVB. As introduction of either GPE or resveratrol induced Nrf2-dependent antioxidant enzymes including heme oxygenase-1 (HO-1) in liver and skin as well as inhibited metalloproteinases, it is highly probable that the extract or resveratrol mitigated UVB-induced photoaging through activation of Nrf2/HO-1 signaling pathway. PRACTICAL APPLICATION: This study proved that resveratrol and the extract of grape peel, a common by-product of grape juice processing, provide effective protection from UV-induced skin wrinkle formation. Therefore, grape peel extract, which contains an appreciable amount of bioactive compound resveratrol, can be utilized as functional food ingredient for the manufacture of inner beauty products.

Fucoxanthin Exerts Cytoprotective Effects against Hydrogen Peroxide-induced Oxidative Damage in L02 Cells

Several previous studies have demonstrated the excellent antioxidant activity of fucoxanthin against oxidative stress which is closely related to the pathogenesis of liver diseases. The present work was to investigate whether fucoxanthin could protect human hepatic L02 cells against hydrogen peroxide- (H₂O₂-) induced oxidative damage. Its effects on H₂O₂-induced cell viability, lactate dehydrogenase (LDH) leakage, intracellular reduced glutathione, and reactive oxygen species (ROS) contents, along with mRNA and protein relative levels of the cytoprotective genes including Nrf2, HO-1, and NQO1, were investigated. The results showed that fucoxanthin could upregulate the mRNA and protein levels of the cytoprotective genes and promote the nuclear translocation of Nrf2, which could be inhibited by the PI3K inhibitor of LY294002. Pretreatment of fucoxanthin resulted in decreased LDH leakage and intracellular ROS content but enhanced intracellular reduced glutathione. Interestingly, pretreatment using fucoxanthin protected against the oxidative damage in a nonconcentration-dependent manner, with fucoxanthin of 5 μM demonstrating the optimal effects. The results suggest that fucoxanthin exerts cytoprotective effects against H₂O₂-induced oxidative damage in L02 cells, which may be through the PI3K-dependent activation of Nrf2 signaling.

Photoprotective Substances Derived from Marine Algae

Marine algae have received great attention as natural photoprotective agents due to their unique and exclusive bioactive substances which have been acquired as an adaptation to the extreme marine environment combine with a range of physical parameters. These photoprotective substances include mycosporine-like amino acids (MAAs), sulfated polysaccharides, carotenoids, and polyphenols. Marine algal photoprotective substances exhibit a wide range of biological activities such as ultraviolet (UV) absorbing, antioxidant, matrix-metalloproteinase inhibitors, anti-aging, and immunomodulatory activities. Hence, such unique bioactive substances derived from marine algae have been regarded as having potential for use in skin care, cosmetics, and pharmaceutical products. In this context, this contribution aims at revealing bioactive substances found in marine algae, outlines their photoprotective potential, and provides an overview of developments of blue biotechnology to obtain photoprotective substances and their prospective applications.

Determination of fucoxanthinol in rat plasma by liquid chromatography-tandem mass spectrometry

Previous studies have indicated that dietary fucoxanthin is mainly converted into fucoxanthinol (the deacetylated form) in mammals, but the pharmacokinetics of fucoxanthinol remains unknown. In this study, after intravenous (i.v.) and intragastric gavage (i.g.) administration of fucoxanthinol to rats at 0.8 and 20 mg/kg respectively, one-step protein precipitation with methanol was employed to prepared plasma samples, and an accurate and precise liquid chromatography-tandem mass spectroscopy (LC-MS/MS) method was developed to determine fucoxanthinol. Plasma samples were resolved by LC-MS/MS on a reverse-phase SB-C18 column equilibrated and eluted with acetonitrile (A, 0.1% formic acid) and water (B, 0.1% formic acid) (A:B = 92:8, v/v) at a flow rate of 0.5 mL/min and the injection volume was 5 μL. Analytes were monitored by Selected-reaction monitoring in positive electrospray ionization mode. The calibration curves for fucoxanthinol were linear over the range 1.17-300 ng/mL. The inter-day and intra-day accuracy and precision were within 1.55%-7.90%. The method was applied successfully in a pharmacokinetic study of fucoxanthinol and the resulting bioavailability was calculated.

Fucoxanthin-Containing Cream Prevents Epidermal Hyperplasia and UVB-Induced Skin Erythema in Mice

Microalgae represent a source of bio-active compounds such as carotenoids with potent anti-inflammatory and antioxidant properties. We aimed to investigate the effects of fucoxanthin (FX) in both in vitro and in vivo skin models. Firstly, its anti-inflammatory activity was evaluated in LPS-stimulated THP-1 macrophages and TNF-α-stimulated HaCaT keratinocytes, and its antioxidant activity in UVB-irradiated HaCaT cells. Next, in vitro and ex vivo permeation studies were developed to determine the most suitable formulation for in vivo FX topical application. Then, we evaluated the effects of a FX-containing cream on TPA-induced epidermal hyperplasia in mice, as well as on UVB-induced acute erythema in hairless mice. Our results confirmed the in vitro reduction of TNF-α, IL-6, ROS and LDH production. Since the permeation results showed that cream was the most favourable vehicle, FX-cream was elaborated. This formulation effectively ameliorated TPA-induced hyperplasia, by reducing skin edema, epidermal thickness, MPO activity and COX-2 expression. Moreover, FX-cream reduced UVB-induced erythema through down-regulation of COX-2 and iNOS as well as up-regulation of HO-1 protein via Nrf-2 pathway. In conclusion, FX, administered in a topical formulation, could be a novel natural adjuvant for preventing exacerbations associated with skin inflammatory pathologies as well as protecting skin against UV radiation.

Natural Antioxidants: Multiple Mechanisms to Protect Skin From Solar Radiation

Human skin exposed to solar ultraviolet radiation (UVR) results in a dramatic increase in the production of reactive oxygen species (ROS). The sudden increase in ROS shifts the natural balance toward a pro-oxidative state, resulting in oxidative stress. The detrimental effects of oxidative stress occur through multiple mechanisms that involve alterations to proteins and lipids, induction of inflammation, immunosuppression, DNA damage, and activation of signaling pathways that affect gene transcription, cell cycle, proliferation, and apoptosis. All of these alterations promote carcinogenesis and therefore, regulation of ROS levels is critical to the maintenance of normal skin homeostasis. Several botanical products have been found to exhibit potent antioxidant capacity and the ability to counteract UV-induced insults to the skin. These natural products exert their beneficial effects through multiple pathways, including some known to be negatively affected by solar UVR. Aging of the skin is also accelerated by UVR exposure, in particular UVA rays that penetrate deep into the epidermis and the dermis where it causes the degradation of collagen and elastin fibers via oxidative stress and activation of matrix metalloproteinases (MMPs). Because natural compounds are capable of attenuating some of the UV-induced aging effects in the skin, increased attention has been generated in the area of cosmetic sciences. The focus of this review is to cover the most prominent phytoproducts with potential to mitigate the deleterious effects of solar UVR and suitability for use in topical application.

Fucoxanthin Elicits Epigenetic Modifications, Nrf2 Activation and Blocking Transformation in Mouse Skin JB6 P+ Cells

Nuclear factor erythroid-2-related factor-2 (Nrf2 or NFE2L2) is a master regulator of the anti-oxidative stress response, which is involved in the defense against many oxidative stress/inflammation-mediated diseases, including anticancer effects elicited by an increasing number of natural products. Our previous studies showed that the epigenetic modification of the Nrf2 gene plays a key role in restoring the expression of Nrf2. In this study, we aimed to investigate the epigenetic regulation of Nrf2 by astaxanthin (AST) and fucoxanthin (FX), carotenoids which are abundant in microalgae and seaweeds, in mouse skin epidermal JB6 P+ cells. FX induced the anti-oxidant response element (ARE)-luciferase and upregulated the mRNA and protein levels of Nrf2 and Nrf2 downstream genes in HepG2-C8 cells overexpressing the ARE-luciferase reporter. Both FX and AST decreased colony formation in 12-Otetradecanoylphorbol-13-acetate (TPA)-induced transformation of JB6 P+ cells. FX decreased the methylation of the Nrf2 promoter region in the JB6 P+ cells by the bisulfite conversion and pyrosequencing. Both FX and AST significantly reduced DNA methyltransferase (DNMT) activity but did not affect histone deacetylase (HDAC) activity in JB6 P+ cells. In summary, our results show that FX activates the Nrf2 signaling pathway, induces the epigenetic demethylation of CpG sites in Nrf2 and blocks the TPA-induced transformation of JB6 P+ cells, indicating the potential health-promoting effects of FX in skin cancer prevention.

Potential biomedical applications of marine algae

Functional components extracted from algal biomass are widely used as dietary and health supplements with a variety of applications in food science and technology. In contrast, the applications of algae in dermal-related products have received much less attention, despite that algae also possess high potential for the uses in anti-infection, anti-aging, skin-whitening, and skin tumor treatments. This review, therefore, focuses on integrating studies on algae pertinent to human skin care, health and therapy. The active compounds in algae related to human skin treatments are mentioned and the possible mechanisms involved are described. The main purpose of this review is to identify serviceable algae functions in skin treatments to facilitate practical applications in this high-potential area.

Current Perspective in the Discovery of Anti-aging Agents from Natural Products

Aging is a process characterized by accumulating degenerative damages, resulting in the death of an organism ultimately. The main goal of aging research is to develop therapies that delay age-related diseases in human. Since signaling pathways in aging of Caenorhabditis elegans (C. elegans), fruit flies and mice are evolutionarily conserved, compounds extending lifespan of them by intervening pathways of aging may be useful in treating age-related diseases in human. Natural products have special resource advantage and with few side effect. Recently, many compounds or extracts from natural products slowing aging and extending lifespan have been reported. Here we summarized these compounds or extracts and their mechanisms in increasing longevity of C. elegans or other species, and the prospect in developing anti-aging medicine from natural products.

Preventive effect of dietary astaxanthin on UVA-induced skin photoaging in hairless mice

Astaxanthin, a carotenoid found mainly in seafood, has potential clinical applications due to its antioxidant activity. In this study, we evaluated the effect of dietary astaxanthin derived from Haematococcus pluvialis on skin photoaging in UVA-irradiated hairless mice by assessing various parameters of photoaging. After chronic ultraviolet A (UVA) exposure, a significant increase in transepidermal water loss (TEWL) and wrinkle formation in the dorsal skin caused by UVA was observed, and dietary astaxanthin significantly suppressed these photoaging features. We found that the mRNA expression of lympho-epithelial Kazal-type-related inhibitor, steroid sulfatase, and aquaporin 3 in the epidermis was significantly increased by UVA irradiation for 70 days, and dietary astaxanthin significantly suppressed these increases in mRNA expression to be comparable to control levels. In the dermis, the mRNA expression of matrix metalloprotease 13 was increased by UVA irradiation and significantly suppressed by dietary astaxanthin. In addition, HPLC-PDA analysis confirmed that dietary astaxanthin reached not only the dermis but also the epidermis. Our results indicate that dietary astaxanthin accumulates in the skin and appears to prevent the effects of UVA irradiation on filaggrin metabolism and desquamation in the epidermis and the extracellular matrix in the dermis.

Protective and therapeutic effects of fucoxanthin against sunburn caused by UV irradiation

Mild exposure to ultraviolet (UV) radiation is also harmful and hazardous to the skin and often causes a photosensitivity disorder accompanied by sunburn. To understand the action of UV on the skin we performed a microarray analysis to isolate UV-sensitive genes. We show here that UV irradiation promoted sunburn and downregulated filaggrin (Flg); fucoxanthin (FX) exerted a protective effect. In vitro analysis showed that UV irradiation of human dermal fibroblasts caused production of intracellular reactive oxygen species (ROS) without cellular toxicity. ROS production was diminished by N-acetylcysteine (NAC) or FX, but not by retinoic acid (RA). In vivo analysis showed that UV irradiation caused sunburn and Flg downregulation, and that FX, but not NAC, RA or clobetasol, exerted a protective effect. FX stimulated Flg promoter activity in a concentration-dependent manner. Flg promoter deletion and chromatin immunoprecipitation analysis showed that caudal type homeo box transcription factor 1 (Cdx1) was a key factor for Flg induction. Cdx1 was also downregulated in UV-exposed skin. Therefore, our data suggested that the protective effects of FX against UV-induced sunburn might be exerted by promotion of skin barrier formation through induction of Flg, unrelated to quenching of ROS or an RA-like action.

Potential for tyndalized Lactobacillus acidophilus as an effective component in moisturizing skin and anti-wrinkle products

It is widely accepted that ultraviolet (UV) irradiation induces skin damage. In the present study, a UVB-induced hairless mouse model of skin photoaging was developed to determine whether tyndalized Lactobacillus acidophilus was able to significantly enhance the repair of photodamaged skin. To evaluate the effects of tyndalized L. acidophilus on UVB-induced skin-wrinkle formation in vivo, HR-1 hairless male mice were exposed to UVB radiation and orally administered tyndalized L. acidophilus. Compared with the control group, the UVB irradiation mice displayed a significant increase in transepidermal water loss and a reduction in skin hydration. In mice with UVB-induced photodamage, the effacement of the fine wrinkles by tyndalized L. acidophilus was correlated with dermal collagen synthesis, accompanied by histological changes. Furthermore, western blotting was performed to investigate the protein expression levels of matrix metalloproteinases (MMPs) and mitogen-activated protein kinase. Notably, orally administered tyndalized L. acidophilus reduced the expression levels of MMP-1 and MMP-9. Based upon the aforementioned results, it was determined that tyndalized L. acidophilus effectively inhibited the wrinkle formation induced by UVB irradiation, and that this may be attributed to the downregulation of MMPs. Therefore, tyndalized L. acidophilus may be considered a potential agent for preventing skin photoaging and wrinkle formation.

Inhibition of Ultraviolet B-Induced Expression of the Proinflammatory Cytokines TNF-α and VEGF in the Cornea by Fucoxanthin Treatment in a Rat Model

Ultraviolet B (UVB) irradiation is the most common cause of radiation damage to the eyeball and is a risk factor for human corneal damage. We determined the protective effect of fucoxanthin, which is a carotenoid found in common edible seaweed, on ocular tissues against oxidative UVB-induced corneal injury. The experimental rats were intravenously injected with fucoxanthin at doses of 0.5, 5 mg/kg body weight/day or with a vehicle before UVB irradiation. Lissamine green for corneal surface staining showed that UVB irradiation caused serious damage on the corneal surface, including severe epithelial exfoliation and deteriorated epithelial smoothness. Histopathological lesion examination revealed that levels of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α) and vascular endothelial growth factor (VEGF), significantly increased. However, pretreatment with fucoxanthin inhibited UVB radiation-induced corneal disorders including evident preservation of corneal surface smoothness, downregulation of proinflammatory cytokine expression, and decrease of infiltrated polymorphonuclear leukocytes from UVB-induced damage. Moreover, significant preservation of the epithelial integrity and inhibition of stromal swelling were also observed after UVB irradiation in fucoxanthin-treated groups. Pretreatment with fucoxanthin may protect against UVB radiation-induced corneal disorders by inhibiting expression of proinflammatory factors, TNF-α, and VEGF and by blocking polymorphonuclear leukocyte infiltration.

Orally administered betaine reduces photodamage caused by UVB irradiation through the regulation of matrix metalloproteinase-9 activity in hairless mice

Betaine is widely distributed in plants, microorganisms, in several types of food and in medical herbs, including Lycium chinense. The administration of 100 mg betaine/kg body weight/day is an effective strategy for preventing ultraviolet irradiation‑induced skin damage. The present study aimed to determine the preventive effects of betaine on ultraviolet B (UVB) irradiation‑induced skin damage in hairless mice. The mice were divided into three groups: Control (n=5), UVB‑treated vehicle (n=5) and UVB‑treated betaine (n=5) groups. The level of irradiation was progressively increased between 60 mJ/cm2 per exposure at week 1 (one minimal erythematous dose = 60 mJ/cm2) and 90 mJ/cm2 per exposure at week 7. The formation of wrinkles significantly increased following UVB exposure in the UVB‑treated vehicle group. However, treatment with betaine suppressed UVB‑induced wrinkle formation, as determined by the mean length, mean depth, number, epidermal thickness and collagen damage. Furthermore, oral administration of betaine also inhibited the UVB‑induced expression of mitogen‑activated protein kinase kinase (MEK), extracellular signal‑regulated kinase (ERK), and matrix metalloproteinase‑9 (MMP‑9). These findings suggested that betaine inhibits UVB‑induced skin damage by suppressing increased expression of MMP‑9 through the inhibition of MEK and ERK.