Proteoglycan Combined with Hyaluronic Acid and Hydrolyzed Collagen Restores the Skin Barrier in Mild Atopic Dermatitis and Dry, Eczema-Prone Skin: A Pilot Study

The Role of Collagens in Atopic Dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease affecting both children and adults. The clinical picture of AD manifests in typical skin lesions, such as localized eczema and dry skin, with dominant, persistent itching that leads to sleep disturbances. The pathophysiology of AD has been extensively investigated with respect to epigenetic and genetic factors, skin barrier defects, as well as immunological and microbial disorders. However, to date, the involvement of extracellular matrix (ECM) elements has received limited attention. Collagen, a major component of the ECM, may serve as a therapeutic target for the future treatment of AD. This paper summarizes the role of collagens, which are the most abundant components of the extracellular matrix in AD.

Technological aspects and health effects of hydrolyzed collagen and application in dairy products

With the rise of a consumer market increasingly concerned with food and healthy lifestyle habits, the search for functional products has increased in the last years. In this context, dairy products are relevant since they are already included in the consumer's diet. Furthermore, hydrolyzed collagen stands out among products with bioactive action, as it promotes the reduction of the incidence of arthritis, osteoporosis, hypertension, obesity, and premature aging and contains healing, antioxidant and antimicrobial properties. In addition to health benefits, the addition of these ingredients to dairy products can influence physical, chemical, rheological, microbiological, and sensory characteristics, such as: decreased syneresis and improved texture of fermented milks; viscosity increase in dairy beverage; increased proteolytic activity in cheeses; and increasing the viability of probiotics, without significantly altering the quality standards of the legislation. Despite the benefits described, more studies are needed to evaluate these effects in different dairy products.

Synthesis and self-assembling of hyaluronan grafted with ceramide NP for topical drug delivery

In this work, amphiphilic hyaluronan was synthesized by grafting succinylated N-oleoyl-phytosphingosine via esters bonds. Succinylated N-oleoyl-phytosphingosine (sCER) was first prepared by esterification of hydroxyl moieties of the ceramide with succinic anhydride. The esterification of hyaluronan was governed by crowding effect. The oligomeric HA-sCER derivatives exhibited a strong self-aggregation as evidenced by a very low critical aggregation concentration (1.9 μg mL-1), higher pyrene binding constant (KB), and the smallest particle size (30 nm) in solution. The self-aggregation properties demonstrated to be a function of the substitution degree and molecular weight of HA. The prepared derivatives were non-cytotoxic towards cell lines NIH-3T3. Nanoparticles prepared using oligomeric HA-sCER derivatives improved the penetration of Nile red dye through the stratum corneum due to their smaller size (≤50 nm). The fluorescence intensity localized at the stratum corneum was higher for oligomeric HA-sCER. A significant inhibition of the pro-inflammatory cytokine interleukin-6 production was observed in vitro in macrophages differentiated from THP-1 cells. These findings showed that HA-sCER constituted a promising active ingredient for cosmetics use.

Anti-atopic dermatitis effect of fish collagen on house dust mite-induced mice and HaCaT keratinocytes

Collagen, a major structural protein in mammalian tissues, is effective against skin wounds and osteoarthritis. Although bovine and porcine collagens have mainly been used, several potential risks of mammalian collagen have led to the use of fish collagen (FC) as an alternative. FC and its peptides are used as common cosmeceutical products because of their antihypertensive, anti-bacterial, and antioxidant activities. Despite the effects of FC on wrinkle reduction, UV-protection, and wound healing, the relationship between FC and atopic dermatitis (AD) has not yet been reported. Therefore, we investigated the anti-AD effects of FC against house dust mite (Dermatophagoides farinae, HDM)-induced AD in NC/Nga mice and TNF-α/IFN-γ-stimulated HaCaT keratinocytes. FC alleviated AD apparent symptoms, such as dermatitis score, transepidermal water loss, epidermal thickness, and mast cell infiltration upon declining pro-inflammatory cytokines and mediators, IL-6, IL-5, IL-13, TSLP, and TNF-α. The skin barrier protein, filaggrin, was also recovered by FC administration in vivo and in vitro. Immune response and skin barrier dysfunction are both mitigated by three routes of FC administration: oral, topical, and both routes via the regulation of IκB, MAPKs, and STATs pathways. In summary, FC could be a potential therapeutic agent for AD by regulating immune balance and skin barrier function.

The EGF Motif With CXDXXXXYXCXC Sequence Suppresses Fibrosis in a Mouse Skin Wound Model

BACKGROUND/AIM

Fibrosis is an essential process for wound healing, but excessive fibrosis, such as keloids and hypertrophic scars, can cause cosmetic and functional problems. These lesions are caused by abnormal deposition and shrinkage of collagen fibers. The light chain of FIX, a plasma protein essential for hemostasis, has the amino acid sequence CXDXXXXYXCXC in the EGF domain. Peptides containing this sequence inhibited stromal growth in a mouse transplant tumor model. In this study, the effect of the FIX light chain on wound healing was studied.

MATERIALS AND METHODS

A full-layer wound was made on the back of each mouse, and cDNA encoding the light chain of mouse FIX (F9-LC) in an expression vector was injected locally once each week using a non-viral vector. Histochemical analysis of the wound was then performed to assess the effects on wound healing. Moreover, the effect of F9-LC on fibroblasts was studied in vitro.

RESULTS

Macroscopic observation showed that wounds with forced expression of F9-LC appeared flatter and had fewer wrinkles than control wounds. Tissue collagen staining and immunostaining revealed that administration of F9-LC suppressed collagen 1 and 3 deposition and decreased α-smooth muscle actin expression. Electron microscopy revealed sparse and disorganized collagen fibers in the F9-LC-treated mice. In experiments using fibroblasts, addition of a recombinant protein of the FIX light chain disrupted the typical spindle shape and alignment of fibroblasts.

CONCLUSION

F9-LC is a new candidate for use in treatments to regulate excessive fibrosis and contraction in wound healing.

The role of short-chain fatty acids in inflammatory skin diseases

Short-chain fatty acids (SCFAs) are metabolites of gut microbes that can modulate the host inflammatory response, and contribute to health and homeostasis. Since the introduction of the gut-skin axis concept, the link between SCFAs and inflammatory skin diseases has attracted considerable attention. In this review, we have summarized the literature on the role of SCFAs in skin inflammation, and the correlation between SCFAs and inflammatory skin diseases, especially atopic dermatitis, urticaria, and psoriasis. Studies show that SCFAs are signaling factors in the gut-skin axis and can alleviate skin inflammation. The information presented in this review provides new insights into the molecular mechanisms driving gut-skin axis regulation, along with possible pathways that can be targeted for the treatment and prevention of inflammatory skin diseases.

Localized Delivery of Bioactives using Structured Liposomal Gels

Liposomes have gained a lot of interest for drug delivery applications, and some of these preparations have been commercialized. These are formulated with biocompatible components and can be used for delivering a wide range of payloads differing in aqueous solubility and molecular weight. Liposome-based delivery approaches are limited mainly by two factors: (a) poor dispersion stability, and (b) pre-mature leakage of payloads. In this review, we have discussed the stabilization of liposomal vesicles by their entrapment in hydrogels. Studies reveal that such hydrogels can maintain the structural integrity of liposomes. Release of liposomes from the hydrogel network can be modulated through careful screening of matrix former and degree of its cross-linking. Accordingly, we have reviewed the approaches of stabilizing liposomal vesicles through entrapment in hydrogels. Application of liposome-embedded hydrogels has been reviewed in context of localized drug delivery. Our discussion is focussed on the delivery of bioactives to the skin. Such an approach appears alluring from the standpoint of minimizing the undesirable distribution of payload(s) the systemic circulation and off-target sites.

In vitro assessment of the anti-inflammatory and skin-moisturizing effects of Filipendula palmata (Pall.) Maxim. On human keratinocytes and identification of its bioactive phytochemicals

ETHNOPHARMACOLOGICAL RELEVANCE

The meadowsweet family (genus Filipendula) includes about 30 species, which have been traditionally used in folk medicine to treat various inflammatory diseases. Particularily, F. palmata (Pall.) Maxim. (Siberian meadowsweet) were traditionally and widely used as an ethnic herb in the Oroqen application.

AIM OF THE STUDY

Limited studies have been documented on most species, except for two main species, F. ulmaria (L.) Maxim. and F. vulgaris Moench. Thus, this study aimed to investigate the anti-inflammatory and skin-moisturizing effects of 70% ethanolic extract (FPE) of F. palmata on human epidermal keratinocytes.

MATERIALS AND METHODS

HaCaT keratinocytes were treated with FPE under different conditions. Quantitative real time-PCR, enzyme-linked immunosorbent assay, western blotting methods were used to evaluate the effect and molecular mechanism of the cells treated with FPE. The bioactive compounds in FPE, which are responsible for biological activities, was explored using mass spectrometric analysis.

RESULTS

FPE did not show a cytotoxic effect on the cells at concentrations below 200 μg/mL. FPE significantly suppressed the intracellular reactive oxygen species and mitochondrial superoxide of inflamed HaCaT cells induced by tumor necrosis factor-α and interferon-γ (T + I) and inflammatory chemokine genes and proteins, such as CC chemokine ligands (CCL5, CCL17, and CCL27) and CXC chemokine ligand (CXCL8). These anti-inflammatory activities of FPE were mediated by the downregulation of mitogen-activated protein kinase (MAPK) and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathways. In normal HaCaT cells, FPE significantly promoted the production of hyaluronic acid (HA) via the downregulation of hyaluronidase (HYAL1 and HYAL2) and upregulation of hyaluronic acid synthase (HAS1, HAS2, and HAS3) genes, and these effects seemed to be associated with the PI3K/Akt/NF-κB signaling. Ultraperformance liquid chromatography-tandem mass spectrometry indicated that FPE contains four flavonoids, including (+)-catechin, miquelianin, scutellarin, and quercitrin, as its major phytochemicals. Finally, we demonstrated that miquelianin and quercitrin contribute partially to the anti-inflammatory and HA-producing activity of FPE without cytotoxic effects on HaCaT cells.

CONCLUSIONS

Our findings suggest that topical applications of FPE can be utilized as an alternative therapy for treating skin inflammation. Additionally, our findings serve as a reference in applying FPE as a functional ingredient to treat inflammatory skin diseases and promote skin health.

Targeting Cellular Senescence with Senotherapeutics: Development of New Approaches for Skin Care

SUMMARY

Aging of the skin is evidenced by increased wrinkles, age spots, dryness, and thinning with decreased elasticity. Extrinsic and intrinsic factors including UV, pollution, and inflammation lead to an increase in senescent cells (SnCs) in skin with age that contribute to these observed pathological changes. Cellular senescence is induced by multiple types of damage and stress and is characterized by the irreversible exit from the cell cycle with upregulation of cell cycle-dependent kinase inhibitors p16INK4a and p21CIP1. Most SnCs also developed an inflammatory senescence-associated secretory phenotype (SASP) that drives further pathology through paracrine effects on neighboring cells and endocrine effects on cells at a distance. Recently, compounds able to kill senescent cells specifically, termed senolytics, or suppress the SASP, termed senomorphics, have been developed that have the potential to improve skin aging as well as systemic aging in general. Here, we provide a summary of the evidence for a key role in cellular senescence in driving skin aging. In addition, the evidence for the potential application of senotherapeutics for skin treatments is presented. Overall, topical, and possibly oral senotherapeutic treatments have tremendous potential to eventually become a standard of care for skin aging and related skin disorders.

The Role of the Extracellular Matrix (ECM) in Wound Healing: A Review

The extracellular matrix (ECM) is a 3-dimensional structure and an essential component in all human tissues. It is comprised of varying proteins, including collagens, elastin, and smaller quantities of structural proteins. Studies have demonstrated the ECM aids in cellular adherence, tissue anchoring, cellular signaling, and recruitment of cells. During times of integumentary injury or damage, either acute or chronic, the ECM is damaged. Through a series of overlapping events called the wound healing phases—hemostasis, inflammation, proliferation, and remodeling—the ECM is synthesized and ideally returned to its native state. This article synthesizes current and historical literature to demonstrate the involvement of the ECM in the varying phases of the wound healing cascade.