Stimulatory Effect of Dietary Red Ginseng on Epidermal Hydration and Ceramide Levels in Ultraviolet-Irradiated Hairless Mice

Protective roles of mesenchymal stem cells on skin photoaging: A narrative review

Skin is a natural barrier of human body and a visual indicator of aging process. Exposure to ultraviolet (UV) radiation in the sunlight may injure the skin tissues and cause local damage. Besides, it is reported that repetitive or long-term exposure to UV radiation may reduce the collagen production, change the normal skin structure and cause premature skin aging. This is termed "photoaging". The classical symptoms of photoaging include increased roughness, wrinkle formation, mottled pigmentation or even precancerous changes. Mesenchymal stem cells (MSCs) are a kind of cells with the ability of self-renewal and multidirectional differentiation into many types of cells, like adipocytes, osteoblasts and chondrocytes. Researchers have explored diverse pharmacological actions of MSCs because of their migratory activity, paracrine actions and immunoregulation effects. In recent years, the huge potential of MSCs in preventing skin from photoaging has gained wide attention. MSCs exert their beneficial effects on skin photoaging via antioxidant effect, anti-apoptotic/anti-inflammatory effect, reduction of matrix metalloproteinases (MMPs) and activation of dermal fibroblasts proliferation. MSCs and MSC related products have demonstrated huge potential in the treatment of skin photoaging. This narrative review concisely sums up the recent research developments on the roles of MSCs in protection against photoaging and highlights the enormous potential of MSCs in skin photoaging treatment.

KGR-BG1, a Standardized Korean Black Ginseng Extract, Has No Significant Effects on Head or Face Temperature Compared with Korean Red Ginseng Extract and a Placebo

There is a lack of studies on the effects of Korean ginseng (Panax ginseng C.A. Meyer) on face or body temperature. Therefore, in this study, we evaluated the effects of a black ginseng extract, KGR-BG1, on head and face temperatures and compared them with those of red ginseng extract and a placebo. We assessed their safety and tolerability and examined changes in the serum levels of biomarkers associated with immune responses, as well as with glucose and lipid metabolism. A randomized, double-blind, placebo-controlled study was conducted with 180 participants. The participants were randomly assigned to the KGR-BG1, red ginseng extract, or placebo group. Each group received a 1500 mg oral dose of their respective substances containing 1000 mg of the active component or placebo twice daily for 6 weeks. After treatment, changes in the head, face, and body temperature were measured, and serum biomarkers were evaluated. A total of 172 participants completed the evaluation after 6 weeks of treatment. No significant differences were observed in the head, face, and body temperatures among the treatment groups. After 6 weeks of treatment, the serum levels of biomarkers associated with inflammation, glucose metabolism, and lipid metabolism were similar to the baseline levels in all treatment groups. KGR-BG1 was well-tolerated compared with red ginseng extract and placebo. KGR-BG1 did not significantly alter head, face, or body temperature, or serum biomarker levels, and it was well tolerated in healthy volunteers over 6 weeks of treatment. Study Registration: Registered at Clinical Research Information Service (CRIS; https://cris.nih.go.kr) as KCT0003126.

Low Molecular Weight Oligosaccharide from Panax ginseng C.A. Meyer against UV-Mediated Apoptosis and Inhibits Tyrosinase Activity In Vitro and In Vivo

To find new anti-UV and whitening agents, 21 fractions isolated from three preparations of ginseng (white, red, and black ginseng) were screened, and their antioxidant effects on AAPH- or H₂O₂-induced damage were investigated. Furthermore, the protective effect against UV-mediated apoptosis and the tyrosinase inhibitory activity of the targeted fractions were evaluated in vitro and in a zebrafish model. Among all fractions, F10 from white ginseng was selected as having the strongest anti-UV and antimelanogenesis activities. This fraction exhibited excellent inhibitory effects on the pigmentation of zebrafish, which may be due to its potential tyrosinase inhibitory activity. Additionally, the chemical composition of F10 was evaluated by UPLC-MS and NMR instruments. The results indicated that F10 had a carbohydrate content of more than 76%, and the weight-average molecular weight was approximately 239 Da. Disaccharide sucrose was the main active compound in F10. These results suggest that F10 could be used as an ingredient for whitening cosmetics and regarded as an anti-UV filter in the future.

Comparative Polyphenol Composition, Antioxidant and Anticorrosion Properties in Various Parts of Panax ginseng Extracted in Different Solvents

Panax ginseng C.A. (P. ginseng) Meyer has been in use since ancient times for its therapeutic activities. Although several studies have investigated the roles of phytoconstituents in human and animal health, no comparative studies have been conducted to test the efficacy of P.ginseng leaf, fruit and root. Therefore, this study aimed to identify the antioxidant and anticorrosion activities of ginseng prepared using five different solvents. The methanolic fruit extract showed comparatively good activity in all assays. The total phenolic content (TPC) was higher in fruit (95.21 mg/g), followed by leaf (39.21 mg/g) extracted in methanol solvent compared other solvents. The total flavonoid content (TFC) of fruit methanolic extract was 50.21 mg/g, which was followed by fruit extracted in ethanol (41.33 mg/g). The same phenomenon was observed in all antioxidant studies. Through Ultrahigh Performance Liquid Chromatography (UHPLC), the presence of 23 phenolic components categorized as hydroxycinnamic acids, hydroxybenzoic acids and a few other groups that play a vital role in antioxidation was identified. Phenols such as chlorogenic acid (1002.2 μg/g), gentisic acid (854.21 μg/g) and rutin (165.32 μg/g) were found in higher amounts in fruit whereas leaf showed significant amounts of m-coumaric acid (185.32 μg/g) and p-coumaric acid (125.24 μg/g). The anti-corrosive property of the fruit extract of the ginseng with methanol as a solvent was analyzed for a copper specimen exposed to 1 M HCl medium and found to have 96% corrosion inhibition efficiency at a 1000-ppm concentration. The smooth surface of the specimen exposed to corrosive media shown in a field emission scanning electron microscope (FESEM) image confirms that the specimen was protected from corrosion, and energy-dispersive X-ray spectroscopy (EDX) spectra show that the loss of Cu is reduced in inhibited metal surface. Atomic force microscopy (AFM) images and surface roughness factor also validate the corrosion inhibition characteristic of ginseng plant extract.

Effect of red ginseng NaturalGEL on skin aging

Background

In aged skin, degradation of collagen fibers, which occupy the majority of the extracellular matrix in the dermis, and changes of aquaporin 3 (AQP3) and skin constituents, such as hyaluronic acid and ceramide, cause wrinkles and decrease skin moisturization to contribute to dryness and lower elasticity skin. Red ginseng (RG) is used as a cosmetic and food material and is known to protect from UVB-induced cell death, increase skin hydration, prevent wrinkles, and have an antioxidative effect. But, in general, RG used as a material is the soluble liquid portion in the solvent, and the part that is not soluble in the solvent is discarded. Thus, we made the whole RG into microgranulation and dispersed in water to produce gel form for using entire RG, and it was named red ginseng NaturalGEL (RG NGEL).

Methods

RG NGEL was investigated for matrix metalloproteinases inhibitory activity, induction of Type I collagen, AQP3, hyaluronan synthetase 2, serine palmitoyl transferase, ceramide synthase 3, and filaggrin expression and compared with RG water extract.

Results

RG NGEL reduced the levels of UV-induced matrix metalloproteinases and increased Type I collagen in human fibroblast cells and upregulated AQP3, hyaluronan synthetase 2, serine palmitoyl transferase, ceramide synthase 3, and filaggrin expressions in human keratinocytes compared with RG water extract.

Conclusion

RG NGEL has the potential as an effective reagent for antiaging cosmetics to improve wrinkle formation and skin hydration.

Wheat Extract Oil (WEO) Attenuates UVB-Induced Photoaging via Collagen Synthesis in Human Keratinocytes and Hairless Mice

The efficacy of wheat extract oil (WEO), standardized to glucosylceramides, for protecting against ultraviolet B (UVB)-induced damage of skin barrier function was assessed using the SHK-1 hairless mouse model and two human skin cell lines, namely, CCD-986sk and HeCaT. The ability of repeated oral administration of 30, 60, and 120 mg of WEO/kg/day for 12 weeks to prevent skin damage of SKH-1 hairless mice induced by UVB irradiation was evaluated. The results demonstrated that UVB-induced water evaporation (transepidermal water loss, TEWL) was significantly decreased by WEO. Similarly, UVB-induced losses in moisture and skin elasticity were improved by WEO supplementation. WEO attenuated the tissue procollagen type I, hyaluronic acid (HA), and ceramide reductions induced by UVB treatment as well. Collagen concentrations in skin tissue were increased in the WEO-treated mice, while UVB-induced epidermal thickening was reduced. In vitro studies using HeCaT human keratinocytes confirmed increased HA and collagen synthesis in response to WEO treatment. This may occur via WEO suppression of matrix metalloproteinase-1 (MMP-1), since its induction by UVB treatment was diminished in treated CCD-986sk cells. Oral administration of WEO improves skin barrier function in UVB-irradiated mice by attenuating damage typically observed in photoaging. This research further clarifies the clinical benefits previously observed by dietary WEO consumption.

1,2-Bis[(3-Methoxyphenyl)Methyl]Ethane-1,2-Dicarboxylic Acid Reduces UVB-Induced Photodamage In Vitro and In Vivo

This study investigated the effects and mechanisms of 1,2-bis[(3-methoxyphenyl)methyl]ethane-1,2-dicarboxylic acid (S4), a sesamin derivative, on anti-inflammation and antiphotoaging in vitro and in vivo. Human skin fibroblasts were treated with S4 and did not show cytotoxicity under concentrations of 5–50 µM. In addition, S4 also reduced ultraviolet (UV)B-induced intracellular reactive oxygen species (ROS) production. Additionally, S4 inhibited UVB-induced phosphorylation of mitogen-activated protein (MAP) kinases, activator protein-1 (AP-1), and matrix metalloproteinases (MMPs) overexpression. Furthermore, S4 also inhibited UVB-induced Smad7 protein expression and elevated total collagen content in human dermal fibroblasts. For anti-inflammatory activity, S4 inhibited UVB-induced nitric oxide synthase (i-NOS) and cyclooxygenase (COX)-2 protein expression and inhibited nuclear factor-kappaB (NF-ĸB) translocation into the nucleus. S4 ameliorated UVB-induced erythema and wrinkle formation in hairless mice. On histological observation, S4 also ameliorated UVB-induced epidermal hyperplasia and collagen degradation. S4 reduced UVB-induced MMP-1, interleukin (IL)-6, and NF-ĸB expression in the mouse skin. The results indicated that S4 had antiphotoaging and anti-inflammatory activities, protecting skin from premature aging.

The use of natural ingredients in innovative Korean cosmeceuticals

BACKGROUND

The cosmeceutical industry is an ever-growing and in demand market, especially in Asia. Korea has been on the forefront of creating the newest generation and most innovative cosmeceuticals products including ingredients such as snail secretions, starfish powder, botanical extracts, green tea, and red ginseng. Given their increasing prevalence in the cosmeceutical industry, scientists have been conducting investigations into these extracts and their properties.

OBJECTIVE

To summarize the current literature surrounding multiple natural ingredients found in Korean cosmeceutical products.

METHODS

A review of the literature surrounding natural ingredients found in Korean cosmeceuticals was conducted using PubMed (U.S. National Library of Medicine).

RESULTS

Multiple natural extracts have been found to have antiaging, antitumor, and antimelanogenic effects making them useful additives in current cosmeceutical products.

CONCLUSION

With the public's increasing awareness of cosmeceutical products, it is important for physicians to understand the properties of these extracts in order to inform patients correctly and ensure patient safety.

Antiinflammatory and Antiphotodamaging Effects of Ergostatrien-3β-ol, Isolated from Antrodia camphorata, on Hairless Mouse Skin

Ergostatrien-3β-ol (EK100), isolated from the submerged whole broth of Antrodia camphorata, has antidiabetic, hyperlipidemic, and hepatoprotective activities. However, the antiphotodamage activity of EK100 has still not been revealed. Inflammation and collagen degradation contribute to skin photodamage and premature aging. In the present study, in vivo experiments were designed to investigate the antiinflammatory and antiphotodamaging activities of EK100 in hairless mice by physiological and histological analysis of the skin. Results indicated that topical application of EK100 (25 and 100 μM) for 10 weeks efficiently inhibited ultraviolet B (UVB)-induced wrinkle formation, erythema, and epidermal thickness in the mice skin. EK100 also restored UVB-induced collagen content reduction in hairless mice skin. In addition, the immunohistochemistry results indicated that EK100 significantly inhibited the UVB-induced expression of matrix metalloproteinase-1 (MMP-1), interleukin-6 (IL-6), inducible nitric oxide synthase (iNOS), and nuclear factor kappaB (NF-κB) in the mouse skin. The expression of these proteins was similar to the Normal group after 100 μM EK100 treatment. EK100 inhibited collagen degradation in the skin through MMP-1 inhibition and antiinflammation. EK100 significantly reduced the transepidermal water loss (TEWL), indicating that EK100 protected skin from UVB-induced damage. Our findings strongly suggest that EK100 has significant beneficial antiinflammatory and antiphotoaging activities and that EK100 can be developed as an antiphotodamaging agent.

Conditioned medium from human bone marrow-derived mesenchymal stem cells promotes skin moisturization and effacement of wrinkles in UVB-irradiated SKH-1 hairless mice

BACKGROUND

Mesenchymal stem cells (MSCs) are promising therapeutic agents for various diseases.

AIMS

To investigate the effects of conditioned medium from human bone marrow-derived mesenchymal stem cells (MSC-CdM) on pro-collagen production and wrinkle formation, we performed in vitro and in vivo experiments.

METHODS

We assessed the effects of MSC-CdM on proliferation and photo-aging in human dermal fibroblasts after UVB exposure using enzyme activity assays for collagen type I secretion and MMP-1. To determine the effect of topically applied MSC-CdM on wrinkle formation, MSC-CdM (1% and 10%) and vehicle (propylene glycol: ethanol, 7 : 3) were applied to the dorsal skin of UVB-irradiated hairless mice for 8 weeks. We examined the effects on wrinkle formation by assessing visual skin grading, replica, tape stripping, transepidermal water loss (TEWL), and skin hydration measurement. We also examined histology of the lesions using hematoxylin-eosin, Masson's trichrome, and immunohistochemical staining.

RESULTS

MSC-CdM markedly reduced UV-induced matrix metalloproteinase-1 expression and increased pro-collagen synthesis in a dose-dependent manner. Our findings suggest that MSC-CdM induces repair of dermal damage and effacement of wrinkles on UVB-irradiated hairless mice through protective effect of hydration.

CONCLUSION

These results support an anti-wrinkle effect of MSC-CdM that involves increased collagen synthesis and suggest that MSC-CdM might be a potential candidate for preventing UV-induced skin damage.

Effect of Dietary Supplementation of Red Ginseng By-product on Laying Performance, Blood Biochemistry, Serum Immunoglobulin and Microbial Population in Laying Hens

This study was carried out to investigate the effect of dietary supplementation of red ginseng by-product (RGB) on the laying performance, blood biochemistry, and microbial population in laying hens. A total of 120 Hy-Line Brown laying hens (75 weeks old) were randomly allotted to 1 of 3 dietary treatments with 4 replicates per treatment. A commercial-type basal diet was prepared, and 2 additional diets were prepared by supplementing 5.0 or 10.0 g/kg of RGB to the basal diet at the expense of corn. The diets were fed to hens on an ad libitum basis for 4 weeks. There were no differences in feed intake, egg weight, and feed conversion ratio during 4 weeks of the feeding trial. However, hen-day egg production was significantly greater (p<0.05) for the RGB treatment groups than that for the basal treatment group. There were no differences in triglyceride, aspartate aminotransferase, and alanine aminotransferase during the 4-week feeding trial. However, RGB supplementation increased (p<0.05) the serum immunoglobulin G (IgG) and IgM content compared with basal treatment group. The total cholesterol was lower (p<0.05) in the RGB treatments groups than that in the basal treatment group. The intestinal Lactobacillus population was greater (p<0.05) for the RGB treatments groups than that for the basal treatment group. However, the numbers of Salmonella and Escherichia coli were not different among dietary treatments. During the entire experiment, there was no significant difference in egg quality among all the treatments. In conclusion, in addition to improving hen-day production, there were positive effects of dietary RGB supplementation on serum immunoglobulin and cholesterol levels in laying hens.

A single-center, randomized, double-blind, placebo-controlled study on the efficacy and safety of "enzyme-treated red ginseng powder complex (BG11001)" for antiwrinkle and proelasticity in individuals with healthy skin

BACKGROUND

During the aging process, skin shows visible changes, characterized by a loss of elasticity and the appearance of wrinkles due to reduced collagen production and decreased elasticity of elastin fibers. Panax ginseng Meyer has been used as a traditional medicine for various diseases due to its wide range of biological activities including skin protective effects. Ginsenosides are the main components responsible for the biological activities of ginseng. However, the protective activities of an enzymatic preparation of red ginseng against human skin aging have not been investigated.

METHODS

The efficacy of an enzyme-treated powder complex of red ginseng (BG11001) in preventing human skin aging was evaluated by oral administration to 78 randomized individuals. All patients were requested to take three daily capsules containing either 750 mg of BG11001 or a placebo vehicle for 24 wk; at the end of the testing period, skin roughness, elasticity, and skin water content were measured.

RESULTS

BG11001 significantly reduced the average roughness of eye wrinkles and the Global Photo Damage Score compared with the placebo, although there were no significant differences in arithmetic roughness average between the groups. In addition, gross elasticity and net elasticity values increased, and transepidermal water loss level decreased, indicating improved skin elasticity and moisture content.

CONCLUSION

In conclusion, enzyme-treated red ginseng extract significantly improved eye wrinkle roughness, skin elasticity, and moisture content. Moreover, enzyme-treated red ginseng extract would be useful substance as a bio-health skin care product.

Epidermal Hydration Is Improved by Enhanced Ceramide Metabolism in Aged C57BL/6J Mice After Dietary Supplementation of Royal Jelly

Epidermal hydration is maintained by the epidermal lipid barrier, of which ceramide (Cer) is the major constituent. We examined the dietary effect of royal jelly (RJ) on epidermal hydration in aged mice. Altered Cer metabolism was further determined by measuring epidermal levels of individual Cer, glucosylceramide (GC), and sphingomyelin (SM) species, and of Cer-metabolizing enzymes. Aged C57BL/6J mice were fed a control diet (group AGED) or diets with 1% RJ harvested from two different areas (groups AGED+RJ1:AGED + RJ2) for 16 weeks. Aged C57BL/6J mice with no dietary intervention (the control group: group C) represented the onset of aging. In group AGED, epidermal levels of hydration, Cer1/2/5/6/7, GC-A/B/C/D, SM1/2/3, and β-glucocerebrosidase (GCase) protein, an enzyme of GC hydrolysis for Cer generation, were lower than in group C; these levels, as well as those of Cer3/4 and acidic sphingomyelinase (aSMase) protein, an enzyme of SM hydrolysis for Cer generation, were higher in group AGED + RJ1 than in group AGED. Despite increases in GC-B, SM1/2/3, and serine palmitoyltransferase2 protein, an enzyme of de novo Cer synthesis, in group AGED + RJ2 to levels higher than in group AGED, epidermal levels of hydration, Cer1-7, GC-A/C/D, GCase, and aSMase proteins were similar in these two groups. Expression of GCase and aSMase mRNAs, and of Cer synthase3 and ceramidase proteins, enzymes of de novo Cer synthesis and degradation, did not differ among groups. Dietary RJ1 improved epidermal hydration by enhancing Cer metabolism with increased levels of all Cer, GC, and SM species, and of GCase and aSMase proteins.

Effect of white, red and black ginseng on physicochemical properties and ginsenosides

A systematic comparison of the ginsenosides and physicochemical properties of white ginseng (WG), red ginseng (RG) and black ginseng (BG) was performed. The purpose of the present study was to identify the effects of the physicochemical properties by steaming process. During the steaming process, ginsenosides transform into specific ginsenosides by hydrolysis, dehydration and isomerization at C-3, C-6 or C-20. Steaming ginseng led to a significant increase in reducing sugar, acidic polysaccharide and phenolic compounds content. Antioxidative properties were investigated using the DPPH (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, compared with BHA (Butylated hydroxyanisole). RG and BG exhibited higher antioxidant activity than WG. The maximum residue level for Benzo(a)pyrene was established to 5 μg/kg in food products. The levels of benzo(a)pyrene in WG and RG were not detected. Benzo(a)pyrene was detected in the BG, the content was 0.17 μg/kg. The scientific achievements of the present study could help consumers to choose different type of ginseng products available on the market.

Analytical Research to Determine the effects of the Components of ONGABO on the Viability of HepG2 Cancer Cells by Using the Sovereign, Minister, Assistant and Courier Principle ()

Objectives:

This study used the basic principle of Oriental medicine, the sovereign, minister, assistant and courier principle (君臣佐使論) to investigate the effects of the component of ONGABO, which is composed of Ginseng Radix (Red Ginseng), Angelica Gigantis Radix, Schisandrae Fructus, Cuscuta Semen and Curcumae tuber on the viability of HepG2 cells.

Methods:

Single and mixed extracts of the component of ONGABO were prepared by lypohilizing powder of Red Ginseng (6-year root from Kanghwa), Angelica Gigantis Radix, Schisandrae Fructus, Cuscuta Semen, Curcumae Tuber (from Omniherb Co., Ltd., Korea) at the laboratory of herbal medicine in Woosuk University and were eluted after being macerated with 100% ethanol for three days. The cell viability of HepG2 was determined by using an absorptiometric analysis with PrestoBlue (Invitrogen) reagent after the plate had been incubated for 48 hours. All of the experiments were repeated three times to obtain the average value and standard deviation. The statistical analysis was done and the correlation factor was obtained by using Microsoft Office Excel 2007 and Origin 6.0 software.

Results:

Although Ginseng Radix (Red Ginseng) and Schisandrae Fructus did not enhance the viability of HepG2 cells, they were shown to provide protection of those cells. On the other hand, Angelica Gigantis Radix decreased the viability of HepG2 cells significantly, Cuscuta Semen and Curcumae Tuber had a small or no effect on the viability of HepG2 cells.

Conclusions:

In the sovereign, minister, assistant and courier principle (君臣佐使論), Ginseng Radix (Red Ginseng) corresponds to the sovereign component because it provides cell protection effects, Angelica Gigantis Radix corresponds to minister medicinal because it kills cells, Schisandrae Fructus corresponds to the assistant medicinal to help red ginseng having cell protect effects. Cuscuta Semen and Curcumae Tuber correspond to the courier medicinal having no effect in cell viability in HepG2. We hope this study provides motivation for advanced research on the sovereign, minister, assistant and courier principle.

Enzyme-processed Korean Red Ginseng extracts protects against skin damage induced by UVB irradiation in hairless mice

UV irradiation is the main factor contributing to skin damages that are associated with an excessive production of matrix-degrading metalloproteinase (MMP)-1 and a deficient expression of collagens. To date, red ginseng has been revealed to possess many biomedical effects, such as anti-aging, anti-oxidation, and anti-inflammatory. In this study, we prepared the Korean Red Ginseng extracts treated with enzyme (KRGE) and investigated the effects of dietary KRGE on the formation of wrinkles generated by UVB irradiation in hairless mice. It was found that KRGE inhibited the UVB-induced formation of wrinkles, epidermal thickness, and skin dryness in hairless mice. Further results also showed that KRGE attenuated UVB-induced MMP-1 level, while accelerated procollagen type I, transforming growth factor-β1 secretion. Interestingly, the expression of profilaggrin and filaggrin in both the epidermis and dermis were decreased due to UVB exposure and reversed by KRGE. The KRGE 0.06% was prior to KRGE 0.24%. In view of these results, which indicated that KRGE protected skin from UVB-induced photodamages, which may not only mediated by regulating of MMP-1 and procollagen type I, but also by increasing the production of profilaggrin and filaggrin. In conclusion, our results suggest that KRGE may be a promising agent for the treatment of skin photodamages. The challenge of KRGE will be expected as cosmeceuticals and nutraceuticals in order to intervene in aging-related degenerative skin changes.

Dietary silk protein, sericin, improves epidermal hydration with increased levels of filaggrins and free amino acids in NC/Nga mice

Epidermal hydration is maintained primarily by natural moisturising factors (NMF), of which free amino acids (AA) are major constituents that are generated by filaggrin degradation. To identify dietary sources that may improve skin dryness of atopic dermatitis (AD), we investigated dietary effects of silk proteins, sericin and fibroin, on epidermal levels of hydration, filaggrins and free AA, as well as PPARγ, peptidylarginine deiminase-3 (PAD3) and caspase-14 proteins involved in filaggrin expression and degradation processes. NC/Nga mice, an animal model of AD, were fed a control diet (group CA: atopic control) or diets with 1 % sericin (group S) or fibroin (group F) for 10 weeks. In group S, epidermal levels of hydration, total filaggrins and total free AA, as well as PPARγ, PAD3 and caspase-14, which were reduced in group CA, were increased to higher or similar levels of a normal control group of BALB/c mice (group C). Furthermore, profilaggrin, a precursor with multiple filaggrin repeats, and three repeat intermediates were increased, while two repeat intermediates and filaggrin were decreased in parallel with increased levels of glutamate and serine, major AA of NMF in group S. Despite increased levels of total filaggrins, total free AA, PPARγ and PAD3, epidermal levels of hydration, glutamate, serine and caspase-14 were not increased, but other minor AA of NMF were highly detected in group F. Dietary sericin improves epidermal hydration in parallel with enhancing profilaggrin expression and degradation into free AA that is coupled with elevated levels of PPARγ, PAD3 and caspase-14 proteins.

Ultraviolet-B irradiation induces epidermal up-regulation of heparanase expression and activity

Heparan sulfate (HS) glycosaminoglycans are abundant components of basement membranes and cell surfaces where they are present associated with specific core-proteins to form proteoglycans, mainly perlecan, glypicans and syndecans. They play many roles such as modulation of cell proliferation and differentiation, cell-matrix adhesion and assembly. It was previously shown that HS content decreases during skin aging. This decrease could be explained either by a decrease of HS synthesis or by an increased activity of its degrading enzyme, heparanase (Hpse-1). Since UV-B irradiation is one of the most important factor for skin photo-damage, we decided to study the effects of UV-B irradiation on heparanase expression and activity in human epidermal keratinocytes. Normal human keratinocytes and reconstructed epidermis were submitted to increasing doses of UV-B. HPSE1 mRNA levels were measured using real time PCR and heparanase enzymatic activity was quantified in human keratinocyte cultures using a microtiter-based assay. Expression and distribution of Hpse-1 were also studied in reconstructed epidermis by immunofluorescence. Both HPSE1 mRNA level and heparanase enzymatic activity were increased after UV-B irradiation of keratinocyte cultures in a time and dose-dependent manner. Protein expression of Hpse-1 was also up-regulated with increasing doses of UV-B in reconstructed epidermis. Increase of Hpse-1 expression and activity in the epidermis after UV-B irradiation could contribute to skin photo-aging.