Regulation of elastase-type endopeptidase activity, MMP-2 and MMP-9 expression and activation in human dermal fibroblasts by fucose and a fucose-rich polysaccharide

Therapeutic Effect of Lecigel, Cetiol®CC, Activonol-6, Activonol-M, 1,3-Propanediol, Soline, and Fucocert® (LCAA-PSF) Treatment on Imiquimod-Induced Psoriasis-like Skin in Mice

The individual ingredients of 1,3-Propanediol, Soline, and Fucocert® (PSF) are often used as cosmetic formulations in skin care. In addition, the mixture of Lecigel, Cetiol®CC, Activonol-6, and Activonol-M (LCAA) is often used as a cosmetic base. However, whether the combination of LCAA with PSF (LCAA-PSF) exerts a therapeutic effect on psoriasis remains unclear. In this study, mice induced with imiquimod (IMQ) were divided into three groups and administered 100 mg/day of LCAA, 100 mg/day of LCAA-PSF, or Vaseline on the dorsal skin of each mouse. Weight-matched mice treated with Vaseline alone were used as controls. Hematoxylin and eosin (H&E) staining and enzyme-linked immunosorbent assay(ELISA) were used to assess tissue morphology and inflammatory cytokines. RNA sequencing analysis was used to predict the mechanism underlying the action of LCAA-PSF against psoriasis, while immunohistochemical analysis validation was used to identify pertinent molecular pathways. The results demonstrated that LCAA-PSF alleviated IMQ-induced keratinocyte differentiation/ proliferation bydecreasingthe serum levels of inflammatory cytokines such as IL-6, TNF-α, IL-23, and IL-17A and the epidermisof TGFβ, Ki67, CK5/6, and VEGF expression, which is associated with angiogenesis and keratinocyte differentiation/ proliferation. These findings highlight the antipsoriatic activity of LCAA-PSF in a psoriasis-like mouse model and suggest this may occurvia the inhibition of inflammatory factor secretionand the TGFβ-related signal pathway.

The role of fibrosis in cardiomyopathies: An opportunity to develop novel biomarkers of disease activity

Cardiomyopathies encompass a spectrum of heart disorders with diverse causes and presentations. Fibrosis stands out as a shared hallmark among various cardiomyopathies, reflecting a common thread in their pathogenesis. This prevalent fibrotic response is intricately linked to the consequences of dysregulated extracellular matrix (ECM) remodeling, emphasizing its significance in the development and progression the disease. This review explores the ECM involvement in various cardiomyopathies and its impact on myocardial stiffness and fibrosis. Additionally, we discuss the potential of ECM fragments as early diagnosis, prognosis, and risk stratification. Biomarkers deriving from turnover of collagens and other ECM proteins hold promise in clinical applications. We outline current clinical management, future directions, and the potential for personalized ECM-targeted therapies with specific focus on microRNAs. In summary, this review examines the role of the fibrosis in cardiomyopathies, highlighting the potential of ECM-derived biomarkers in improving disease management with implications for precision medicine.

Research progress on the functions, preparation and detection methods of l-fucose

l-fucose is a six-carbon sugar that has potential applications in many fields. It exerts antitumor effects and could relieve intestinal disease. It exhibits potential as an emulsifier in the food industry. It is also used as a functional food and in anti-aging skincare products. However, at present, it is not possible to prepare high-purity l-fucose on a large scale, and its preparation needs further development. This review summarizes the preparation methods of l-fucose including chemical synthesis, enzymatic synthesis, microbial fermentation, and separation and purification from algae. The detection methods of l-fucose are also introduced in detail, such as l-fucose-specific lectin, detection l-fucose dehydrogenase, cysteine-sulfuric acid method, high-performance liquid chromatography, gas chromatography, and biosensors. In this review, the properties and pharmacological effects of l-fucose; preparation methods, and the commonly used detection methods of l-fucose are reviewed to serve as a reference material.

The effects of fucoidan-rich polysaccharides extracted from Sargassum horneri on enhancing collagen-related skin barrier function as a potential cosmetic product

BACKGROUND

Sargassum horneri came ashore after flowing from the South China Sea to Jeju Island a few years ago. This caused a significant environmental impact on coastal areas where S. horneri has accumulated because of decomposition and the release of toxic substances, such as hydrogen sulfide.

AIMS

In this study, we evaluated a biological ingredient prepared from fucoidan-rich S. horneri and demonstrated its antiwrinkle effects on ultraviolet B (UVB)-induced fibroblast cells.

MATERIALS AND METHODS

Fucoidan samples from S. horneri were prepared according to a previously published process with modifications. The compositional analysis of S. horneri fucoidan extract (SHFE) as well as its effects on antiaging were examined to determine its utility as a functional material.

RESULTS

SHFE exhibited antioxidant properties using 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay. Treatment of UVB-induced fibroblasts with SHFE significantly increased the synthesis of procollagen compared with adenosine treatment and inhibited MMP-1 and MMP-3 expression. In a clinical study, SHFE lotion improved skin barrier effects in forearms and transepidermal water loss (TEWL) values were reduced after 3 weeks of use compared with a placebo.

CONCLUSION

SHFE has utility as an additive with functional antiaging effects for a range of cosmetic products as it restores skin hydration in the epidermal barrier.

Mass Spectrometry Approach for Differentiation of Positional Isomers of Saccharides: Toward Direct Analysis of Rare Sugars

Rare sugars have gained popularity in recent years due to their use in antiaging treatments, their ability to sweeten with few calories, and their ability to heal infections. Rare sugars are found in small quantities in nature, and they exist typically as isomeric forms of traditional sugars, rendering some challenges in their isolation, synthesis, and characterization. In this work, we present the first direct mass spectrometric approach for differentiating structural isomers of sucrose that differ only by their glycosidic linkages. The method employed a noncontact nanoelectrospray (nESI) platform capable of analyzing minuscule volumes (5 μL) of saccharides via the formation of halide adducts ([M+X]-; X = Cl and Br). Tandem mass spectrometry analysis of the five structural isomers of sucrose afforded diagnostic fragment ions that can be used to distinguish each isomer. Detailed mechanisms showcasing the distinct fragmentation pattern for each isomer are discussed. The method was applied to characterize and confirm the presence of all five selected rare sugars in raw honey complex samples. Aside from the five natural α isomers of sucrose, the method was also suitable for differentiating some β isomers of the same glycosidic linkages, provided the monomeric sugar units are different. The halide adduct formation via the noncontact nESI source was also proven to be effective for oligosaccharides such as raffinose, β-cyclodextrin, and maltoheptaose. The results from this study encourage the future development of methods that function with simple operation to enable straightforward characterization of small quantities of rare sugars.

Renewable marine polysaccharides for microenvironment-responsive wound healing

Marine polysaccharides (MPs) are an eco-friendly and renewable resource with a distinctive set of biological functions and are regarded as biological materials that can be in contact with tissues and body fluids for an extended time and promote tissue or organ regeneration. Skin tissue is easily invaded by the external environment due to its softness and large surface area. However, the body's natural physiological healing process is often too slow or suffers from the incomplete restoration of skin structure and function. Functional wound dressings are crucial for skin tissue engineering. Herein, popular MPs from different sources are summarized systematically. In particular, the structure-effectiveness of MP-based wound dressings and the physiological remodeling process of different wounds are reviewed in detail. Finally, the prospect of MP-based smart wound dressings is stated in conjunction with the wound microenvironment and provides new opportunities for high-value biomedical applications of MPs.

Antiaging effect of inotodiol on oxidative stress in human dermal fibroblasts

Oxidative damage is one of the major causes of human skin aging. Inotodiol is a lanostane triterpenoid that demonstrates antiviral, anticancer, and anti-inflammatory activities. Previous studies have reported that inotodiol also has antiallergic effects. However, whether inotodiol inhibits oxidative stress-induced human skin aging is not known. Stimulation of human dermal fibroblast cells with hydrogen peroxide is related to skin aging. Inotodiol inhibited the expression of mitogen-activated protein kinase (MAPK) and NADPH Oxidase 5 (NOX5). Moreover, inotodiol effectively decreased nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), as well as nitric oxide (NO), reactive oxygen species (ROS), cyclooxygenase-2 (COX-2), and cytokines such as IL-1β, IL-6, and TNF-α. Based on our results, inotodiol protects human dermal fibroblast by preventing MAPK-NOX5 and NF-κB activation and attenuates the expression of aging genes. Inotodiol may therefore be considered a potential candidate for developing natural antiaging products, because it protects the human skin from oxidative stress-induced skin aging by inhibiting the MAPK-NOX5 and NF-κB signaling pathways.

Anti-Photoaging Effects of Low Molecular-Weight Fucoidan on Ultraviolet B-Irradiated Mice

Ultraviolet (UV) B exposure induces DNA damage and production of reactive oxygen species (ROS), which causes skin photoaging through signaling pathways of inflammation and modulation of extracellular matrix remodeling proteins, collagens, and matrix metalloproteinase (MMP). As low molecular-weight fucoidan (LMF) has potential antioxidant and anti-inflammatory properties, we examined the protective effects of LMF against UVB-induced photoaging. A UVB-irradiated mouse model was topically treated with myricetin or LMF at 2.0, 1.0 and 0.2 mg/cm² (LMF2.0, LMF1.0 and LMF0.2, respectively) once a day for 15 weeks. Wrinkle formation, inflammation, oxidative stress, MMP expression, and apoptosis in the treated regions were compared with those in a distilled water-treated photoaging model (UVB control). LMF treatments, particularly LMF2.0 and LMF1.0, significantly inhibited the wrinkle formation, skin edema, and neutrophil recruitment into the photo-damaged lesions, compared with those in the UVB control. While LMF decreased interleukin (IL)-1β release, it increased IL-10. The LMF treatment inhibited the oxidative stresses (malondialdehyde and superoxide anion) and enhanced endogenous antioxidants (glutathione). Additionally, LMF reduced the mRNA expression of MMP-1, 9, and 13. The histopathological analyses revealed the anti-photoaging effects of LMF exerted via its antioxidant, anti-apoptotic, and MMP-9-inhibiting effects. These suggest that LMF can be used as a skin-protective remedy for photoaging.

Mid-dermal elastolysis: A female-centric disease; case report and updated review of the literature

Background

Mid-dermal elastolysis (MDE) is a rare, yet well-defined clinical and histopathologic entity manifested by fine wrinkling of the skin and mid-dermal loss of elastic fibers. This disease predominantly affects young to middle-aged Caucasian females and although it has no reported systemic features, it is psychologically bothersome and can be of great cosmetic concern.

Methods

We report a case of a healthy 45 year-old female with widespread mid-dermal elastolysis. A literature search using the search terms “mid-dermal elastolysis,” “mid dermal elastolysis,” “middermal elastolysis,” and “elastophagocytosis” was conducted on Pubmed, using articles published from January 2008 until November 2014 to accompany Gambichler’s comprehensive 1977 to 2009 review of mid-dermal elastolysis. The references of relevant papers were reviewed and further cases included as appropriate.

Results

We review the clinical features and histological, ultrastructural, and immunohistochemical findings of MDE, as well as differential diagnoses. There are 13 new publications of MDE since 2008. The novel findings since Gambichler’s review are discussed and pathomechanisms revisited. Interestingly, given the striking female predominance of MDE, there is no known hormonal role in its etiology.

Skin mirrors human aging

Abstract Aged skin exhibits disturbed lipid barrier, angiogenesis, production of sweat, immune functions, and calcitriol synthesis as well as the tendency towards development of certain benign or malignant diseases. These complex biological processes comprise endogenous and exogenous factors. Ethnicity also markedly influences the phenotype of skin aging. The theories of cellular senescence, telomere shortening and decreased proliferative capacity, mitochondrial DNA single mutations, the inflammation theory, and the free radical theory try to explain the biological background of the global aging process, which is mirrored in the skin. The development of advanced glycation end-products and the declining hormonal levels are major factors influencing intrinsic aging. Chronic photodamage of the skin is the prime factor leading to extrinsic skin aging. The deterioration of important skin functions, due to intrinsic and extrinsic aging, leads to clinical manifestations, which mirror several internal age-associated diseases such as diabetes, arterial hypertension and malignancies.

Ultraviolet radiation and skin aging: roles of reactive oxygen species, inflammation and protease activation, and strategies for prevention of inflammation-induced matrix degradation - a review

Inflammation and the resulting accumulation of reactive oxygen species (ROS) play an important role in the intrinsic and photoaging of human skin in vivo. Environmental insults such as ultraviolet (UV) rays from sun, cigarette smoke exposure and pollutants, and the natural process of aging contribute to the generation of free radicals and ROS that stimulate the inflammatory process in the skin. UV irradiation initiates and activates a complex cascade of biochemical reactions in human skin. In short, UV causes depletion of cellular antioxidants and antioxidant enzymes (SOD, catalase), initiates DNA damage leading to the formation of thymidine dimmers, activates the neuroendocrine system leading to immunosuppression and release of neuroendocrine mediators, and causes increased synthesis and release of pro-inflammatory mediators from a variety of skin cells. The pro-inflammatory mediators increase the permeability of capillaries leading to infiltration and activation of neutrophils and other phagocytic cells into the skin. The net result of all these effects is inflammation and free radical generation (both reactive oxygen and nitrogen species). Furthermore, elastsases and other proteases (cathepsin G) released from neutrophils cause further inflammation, and activation of matrix metalloproteases. The inflammation further activates the transcription of various matrixes degrading metalloproteases, leading to abnormal matrix degradation and accumulation of non-functional matrix components. In addition, the inflammation and ROS cause oxidative damage to cellular proteins, lipids and carbohydrates, which accumulates in the dermal and epidermal compartments, contributing to the aetiology of photoaging. Strategies to prevent photodamage caused by this cascade of reactions initiated by UV include: prevention of UV penetration into skin by physical and chemical sunscreens, prevention/reduction of inflammation using anti-inflammatory compounds (e.g. cyclooxygenase inhibitors, inhibitors of cytokine generation); scavenging and quenching of ROS by antioxidants; inhibition of neutrophil elastase activity to prevent extracellular matrix damage and activation of matrix metalloproteases (MMPs), and inhibition of MMP expression (e.g. by retinoids) and activity (e.g. by natural and synthetic inhibitors).

Mid-dermal elastolysis revisited

The clinical as well as histological data of 79 mid-dermal elastolysis (MDE) patients reported in the literature were evaluated. MDE is an acquired skin condition of the elastic tissue predominantly manifesting on the trunk and proximal extremities of young women. Most commonly observed skin changes include patches of well-circumscribed fine wrinkles (type I) and perifollicular papular protrusions (type II). Rarely, MDE may also occur with persistent reticular erythema and wrinkling (type III). The critical diagnostic histopathological feature of MDE is the selective loss of elastic fibres in the mid-dermis. Mild lymphohistiocytic infiltrates, elastophagocytosis of elastic fibres by macrophages, and even multinucleate giant cells are occasionally observed in MDE lesions. Immunohistological studies and cell culture experiments indicate that dysbalances in elastin turnover are associated with pathological degradative processes including increased elastolytic activity that finally lead to loss of elastic fibres in the mid-dermis. First-line differential diagnoses may include closely related conditions such as anetoderma, annular elastolytic giant cell granuloma, cutis laxa acquisita and pseudoxanthoma elasticum-like papillary dermal elastolysis. Future therapeutic approaches in MDE patients should focus on agents that are able to block increased elastase activity and induce elastin synthesis.

Role of matrix metalloproteinases in skin ageing

Matrix metalloproteinases are a family of ubiquitous endopeptidases playing a role in many different physiological and pathological processes in the skin. They are also involved in cutaneous ageing. This review summarizes the features and regulation of these enzymes and presents an overview of the molecular mechanisms of both intrinsic and extrinsic skin ageing presents. The role of matrix metalloproteinases in skin ageing is discussed in detail.

Bowman-Birk inhibitor suppresses autoimmune inflammation and neuronal loss in a mouse model of multiple sclerosis

The Bowman-Birk inhibitor (BBI) is a soybean-derived serine protease inhibitor. BBI concentrate (BBIC) is an extract enriched with BBI, but predominantly contains other ingredients including several protease inhibitors. We previously found that BBIC administration to Lewis rats with experimental autoimmune encephalomyelitis (EAE) significantly suppresses disease. In the present study we determined whether BBI mediates the suppressive effects of BBIC in EAE, evaluated its potential neuroprotective effects, and investigated mechanisms of BBI action. We tested effects of purified BBI on clinical and histopathological parameters of EAE in two models (relapsing/remitting EAE in SJL/J mice and chronic EAE in C57BL/6 mice). Effects of BBI were compared to BBIC in relapsing/remitting EAE, and effects of BBI on neuronal survival were examined during acute optic neuritis. Treatment with BBI in both EAE models significantly improved EAE disease parameters (onset, severity, weight loss, inflammation and demyelination). BBI significantly reduced the incidence of optic neuritis and prevented loss of retinal ganglion cells. In most experiments proliferation of immune cells derived from BBI-treated mice was significantly lower relative to control groups. Using Boyden's chamber assay we found that BBI inhibited invasiveness of activated splenocytes through the matrigel barrier. BBI also induced higher production of EAE-suppressive cytokine IL-10 by immune cells. These results demonstrate that BBI is the active component of BBIC that ameliorates clinical EAE. BBI reduces inflammation and attenuates neuronal loss, making it an excellent candidate for oral therapy in MS. BBI likely ameliorates EAE by inhibiting multiple pathways involved in disease pathogenesis.

Inhibition activity of sulfated polysaccharide of Sepiella maindroni ink on matrix metalloproteinase (MMP)-2

SIP-SII is the sulfated S. maindroni ink polysaccharide (SIP) isolated from cuttlefish Sepiella maindroni. SIP-SII weakly inhibited tumor cell growth without cytotoxicity in vitro assay. Herein, we examined the effects of SIP-SII on the expression of matrix metalloproteinase MMP-2 and MMP-9 as well as tumor cell invasion and migration. SIP-SII (0.8-500 microg/ml) significantly decreased the expression of MMP-2 activity in human ovarian carcinoma cells SKOV3 as evidenced by the gelatin zymography analysis. No significant decrease of MMP-9 was detected in the cell line after SIP-SII treatment. The expression of MMP-2 was also evaluated using Western blot analysis. The results showed that SIP-SII inhibited the expression of MMP-2 in SKOV3 and human umbilical vein vascular endothelial cells ECV304 after 24 h incubation. Furthermore, the activity of invasion and migration of SKOV3 and ECV304 cells were measured. SIP-SII displayed an inhibitory effect on the penetration of SKOV3 cells through Matrigel-coated membrane in transwell chamber. A significant inhibition of ECV304 cell migration was observed in the presence of SIP-SII. These results suggest that SIP-SII might suppress invasion and migration of carcinoma cells via inhibition of MMP-2 proteolytic activity.

The effect of cell-matrix interactions and aging on the malignant process

The malignant process, transformation of normal cells, proliferation, and metastasis formation, was considered as if originating from one single cell. Although the intrinsic mechanisms of transformation from the normal to the malignant state were both confirmed, an increasing body of evidence points to the surrounding matrix and cell-matrix interactions as major players in this process. Some of the most important arguments in favor of this contention are cited and commented in this chapter. Another important question concerns the relationship between the aging process and malignant transformation. A few decades ago, the frequency of clinically manifest tumors of several organs and tissues appeared to increase with age. As, however, average life expectancy increased rapidly over the last decades, clinical frequency of malignant tumors did not follow this tendency. It was argued that late in life the malignant process appears to decline. This justly inspired several teams to study the relationship between cellular senescence and malignant transformation. This is now an actively growing field which deserves special attention. Some of the pertinent experimental and theoretical arguments in favor of an antioncogene-mediated switch between these two processes are also reviewed with the caveat that this important and new subject of basic and clinical research on the malignant process is just at its beginning. It will certainly take an increasing importance during the coming years and decades with the hope to contribute to answer one of the most burning questions concerning the aging process: will life expectancy continue to increase linearly as predicted by some gerontologists, or will life expectancy level off or even decline as predicted by other epidemiologists. The relationship between cellular senescence and malignant transformation will play in this respect an important role.

Burn injury reveals altered phenotype in mannan-binding lectin-deficient mice

Burn injury destroys skin, the second largest innate immune organ in the body, and triggers chaotic immune and inflammatory responses. The pattern recognition molecule, mannan-binding lectin (MBL), plays an important role in the first-line host defense against infectious agents. MBL initiates the lectin complement pathway and acts as an opsonin. Recent studies suggest that MBL also modulates inflammatory responses. We report that local responses after burn in MBL null mice differ from those found in wild-type (WT) mice in the following important biological markers: spontaneous eschar separation, thinned epidermis and dermis, upregulation of soluble factors including cytokines, chemokines, cell adhesion molecules, a growth factor-binding protein, and matrix metalloproteinases. Mice lacking C1q, C4, or C3 did not show the lack of eschar separation seen in MBL null-burn phenotype. These findings implicate MBL as an important molecule in the maintenance of the homeostatic balance.

Chitooligosaccharides inhibit activation and expression of matrix metalloproteinase-2 in human dermal fibroblasts

Recently, much attention has been given to chitosan and its hydrolyzed products due to their diverse biological activities. For the first time here we report the inhibitory effect of chitooligosaccharides (COS) on activation and expression of matrix metalloproteinase-2 (MMP-2) in primary human dermal fibroblasts (HDFs). COS with 3-5 kDa exhibited the highest inhibitory effect on MMP-2 activity in HDFs assessed by gelatin zymography. Interestingly, protein expression of MMP-2 was also inhibited by COS with same molecular weight. This inhibition was caused by the decrease of the gene expression and transcriptional activity of MMP-2. Furthermore, it was found that COS repressed the gene expression of c-fos, a part of AP-1 transcription factor. These results suggest that COS may play an important role in the prevention and treatment of MMP-2 mediated several health problems such as metastasis and wrinkle formation.

Effect of a preparation containing a fucose-rich polysaccharide on periorbital wrinkles of human voluntaries

BACKGROUND

Skin aging is accompanied by wrinkle formation. At some sites, as the periorbital skin, this is a relatively early phenomenon, variable from one woman to the other and even between the right and left eye.

PURPOSE

We tested the effect of a preparation with fucose-rich oligo- and polysaccharide (FROP-3) on periorbital wrinkles (crow's feet) on a team of voluntaries.

METHOD

The efficiency of a preparation containing as active principle a fucose-rich polysaccharide in a base-cream for the treatment of temporal periorbital wrinkles on 20 voluntary women was tested as follows: the women applied the cream twice a day for 4 weeks. Negative replicas were taken on the periorbital skin before and after 4 weeks of application of the cream. The results were evaluated by semi-automated morphometry on the plastic replicas and expressed as the 'wrinkle-factor' obtained by multiplying total wrinkle length in millimeters by the average wrinkle width.

RESULTS

After 4 weeks of treatment, there was a significant improvement of the periorbital wrinkles for the majority of the voluntary team who tested the cream. On the 29 periocular wrinkles examined 65% showed an improvement at the end of the treatment. In two cases, the improvement was 100% on one eye (disappearance of the crow's feet) and of 75% and 79% on the other eye. On six eyes, there was no significant change after the end of the treatment, and on four eyes a worsening was observed. The age-dependent modifications showed that improvement was independent of age and was the result of individual skin reactions to the cream. The occurrence and the severity of crow's feet is highly individual, and differs from one side of the face to the other for the same person. These strong individual variations explain the highly variable results, not only from one woman to the other but also comparing one side of the face to the other for the same person.

CONCLUSION

Under the effect of 4 weeks of treatment with the FROP-3-containing cream, most of the voluntaries had their periorbital wrinkles attenuated and some women showed a total regression of crow's feet on one of their eyes.

Pharmacology of skin aging. Stimulation of glycosaminoglycan biosynthesis by L-fucose and fucose-rich polysaccharides, effect of in vitro aging of fibroblasts

The effect of L-fucose and fucose-rich polysaccharides (FROP-s [Biomed. Pharmacother., 2003; 57: 187-94]) was investigated, using human skin fibroblast cultures at several passages. The cells were incubated with radioactive glucosamine for 24 h, followed by the determination of individual glycosaminoglycans (GAG-s) by selective hydrolysis using specific enzymes. The effect of L-fucose and of FROP-3 [Biomed. Pharmacother., in 2003; 57: 187-94], both at 1 and 10 microg/ml, added to the culture medium, was investigated. L-Fucose stimulated the incorporation of the tracer in heparan sulfates by fibroblasts at the ninth passage by 20%. FROP-3 stimulated incorporation in keratan sulfates by 45% by fibroblasts of the fifth passage. This effect was identical at both concentrations tested. For fibroblasts at the ninth passage FROP-3 stimulated incorporation in dermatan sulfate. This effect was dose dependent of the order of +67% at 1 microg/ml and +128% at 10 microg/ml. Incorporation in hyaluronan was also stimulated by about +27%. These stimulations of GAG-biosynthesis might play a role in the increase of total skin thickness of hairless rats treated with L-fucose, as well as in several other favorable results recorded for FROP-3 such as the increased hydration (resistance to pressure) and elasticity of human skin (Robert C, Robert AM, Robert L).

Effect of L-fucose and fucose-rich polysaccharides on elastin biosynthesis, in vivo and in vitro

With increasing age elastic fibres in human skin are progressively lysed and skin elasticity is also decreasing. Still there is an age-dependent increase of elastic fibre surface density, mostly due to an alteration of the fibres. The present experiments were undertaken to explore if L-fucose and fucose-rich polysaccharides (FROP-s) could influence elastin biosynthesis. We show here, that topical application of a fucose-containing preparation to the skin of hairless rats increased after 4 weeks the elastic fibre surface density by about 40%, shown by quantitative morphology. Using human skin fibroblasts in explant cultures, the addition of L-fucose or of FROP-3 increased the biosynthesis of immunoprecipitable tropoelastin by about 40%. No increase was found however of desmosine-isodesmosine in skin explant cultures after 72 h of incubation. The effect of L-fucose and FROP-3 on the biosynthesis of collagen and non-collagen proteins excreted by the skin explant cultures was also investigated. L-fucose, but not FROP-3, decreased collagen biosynthesis but both increased non-collagen protein biosynthesis. These results show that L-fucose and FROP-3 stimulate tropoelastin biosynthesis in vitro, and elastic fibre formation in vivo. This stimulation concerns also several non-collagen proteins secreted by skin explant cultures. Elastic fibre formation necessitates the simultaneous synthesis of several microfibrillar glycoproteins as well as of tropoelastin. The increased elastic fibre density in the in vivo experiments suggests that this is indeed achieved by L-fucose and FROP-3, further demonstrating their efficiency in the control of age-dependent modifications of connective tissues in general and of skin in particular.

Effects of L-fucose and fucose-rich oligo- and polysaccharides (FROP-s) on collagen biosynthesis by human skin fibroblasts. Modulation of the effect of retinol, ascorbate and α-tocopherol

The action of L-fucose and a fucose-rich oligosaccharide (FROP-3) on skin explant cultures and fibroblast cell cultures, alone or together with three vitamins (A, C, E, often used in topical preparations) was studied, using as criteria collagen accumulation and collagen and non-collagen protein biosynthesis. In order to confirm the results observed, several variants of the chemical procedure were used. Collagen accumulation in cell cultures and (3)H-proline incorporation in proteins and collagen gave comparable results. L-Fucose produced a slight but significant inhibition of collagen accumulation and of incorporation of radioactive proline in cell associated collagen and also modified the ratio of excreted (soluble) to cell- or tissue-bound collagen and non-collagen proteins. The oligosaccharide (FROP-3) did not produce a comparable inhibition of collagen biosynthesis. Both L-fucose and FROP-3 modulated the action of the two above-mentioned vitamins in most experimental conditions used. The combined action of the three vitamins (all-trans retinol, ascorbate, alpha-tocopherol) with L-fucose and even more so with FROP-3 can be considered as favourable for the modulation of the biosynthetic activity of fibroblasts.

Studies on skin aging. Preparation and properties of fucose-rich oligo- and polysaccharides. Effect on fibroblast proliferation and survival

Skin aging represents an important chapter of connective tissue aging and concerns an organ of vital importance. Here we describe the preparation as well as the biological properties of fucose-rich oligo- and polysaccharides (FROPs), composed of polymers of a trisaccharide containing galactose, acetyl galacturonic acid and fucose, from the original high molecular weight bacterial polysaccharide (Fucogel), Solabia, France). Using endoglycosidases, oligo- and polysaccharides were prepared and characterized by physical and chemical procedures. The non-reducing end-groups comprise equal amounts of galactose and fucose. The here-described biological properties are: stimulation of cell proliferation of cultured human skin fibroblasts, protection of cells against ascorbate-induced cytotoxicity due to the release of reactive oxygen species (ROS). Properties elsewhere described concern the inhibition of matrix metallo-proteinases 2 and 9 (MMP-2 and MMP-9), their expression and activation. Using fluorescein isothiocyanate (FITC)-labeled polysaccharides, their interaction with cell membranes and also their penetration and accumulation in cells, especially in the cell nucleus could be demonstrated, probably via cell-membrane receptor-mediated mechanisms. We describe some of the symptoms of skin aging and show, that the here-described polysaccharide preparations are susceptible to slow down some of the cellular and molecular mechanisms involved, partly by the mediation of the above-mentioned receptors, partly by acting directly on the regulation of gene expression.

Effect of L-fucose and fucose-rich oligo- and polysaccharides (FROP-s) on skin aging: penetration, skin tissue production and fibrillogenesis

Skin thickness is decreasing with age. This loss concerns both dermis and epidermis, cells and extracellular matrix. We could show here that percutaneous application of an L-fucose-containing preparation produced an increase of skin thickness and a densification of collagen bundles. We also could show that 3H-L-fucose penetrates in the dermis, a prerequisite for the above mentioned favorable pharmacological activities. These results, together with the previous favorable activities on the downregulation of matrix-degrading enzymes, free radical scavenging and increased cell proliferation confirm the favorable action of fucose and fucose-rich polysaccharides (FROP-s) on the skin by slowing down its aging.

Pharmacological properties of fucose. Applications in age-related modifications of connective tissues

Fucose is the only component of glycoconjugates of vertebrates in the L-configuration. It exhibits a number of unique and interesting biological properties reviewed briefly in this article. Its constant end-standing position on glycan chains predisposes fucose to play a key role in cell-cell and cell-matrix interactions, mediated by several receptors such as those recognising the Lewis-type blood group substances, fucose-recognising lectines and the mannose-fucose receptors. Some of the as yet unstudied or less well understood properties of L-fucose were explored in the present study, as its non-enzymatic interaction with amine-groups on macromolecules, its cellular uptake attributed to specific transport mechanisms and its effect on fibroblast cell cultures. We could document the stimulation of cell-proliferation and the inhibition of MMP-expression and activation, both for MMP-2 and MMP-9. These and the other shortly reviewed properties of L-fucose may play an important role in its biological applications and actions.

Protection by L-fucose and fucose-rich polysaccharides against ROS-produced cell death in presence of ascorbate

It was shown previously, that millimolar concentrations of ascorbate have cytotoxic and anti-proliferative effects (Eur. J. Clin. Invest. 32 (2002) 372). With increasing concentrations of ascorbate an increasing number of fibroblasts was detached from the culture dish and shown to be lysed by the effect of ascorbate-induced generation of reactive oxygen species (ROS-s). It also could be shown, that this cytotoxic effect is partly due to the dose-dependent inhibition by ascorbate of fibronectin biosynthesis. Superoxide dismutase (SOD) and catalase were shown to salvage cells from ROS-induced cell-death by preventing the inhibition of fibronectin biosynthesis. We used this model system to test the cyto-protective effect of L-fucose and fucose-rich oligo- and polysaccharides (FROP-s). It appeared that relatively low concentrations of L-fucose and FROP-3 (Biomed. Pharmacother. in press) could efficiently protect fibroblasts from the ascorbate-induced cell-death. These novel pharmacological properties of L-fucose and FROP-3 might well be related to their accelerating effect of wound healing.