BM Skin Care
BM skin care consists of products to clean, tone and protect your complexion. These products are formulated with stem cells and growth factors that help your skin look healthy. These products are often called anti-aging.
Considering the important roles of the DEJ in skin homeostasis, modulation of the basement membrane comprising proteins has been proposed as an anti-aging strategy. The present study investigated the anti-aging effects of peptide derivatives that stimulate epidermal protein expression by using a combination of in vitro cell culture and ex vivo human skin models.
Biotinylated peptides
The dermal-epidermal junction (DEJ) is a physical and biological interface between the epidermis and the dermis. It provides a passageway for molecular transport. Recently, it was found that peptides that stimulate the DEJ can reduce skin wrinkles. In this study, a peptides complex that stimulates dermal basement membrane proteins was developed and its anti-wrinkle efficacy was confirmed in in vitro and ex vivo studies.
This complex consists of six biotinylated peptides: biotinyl nidogen, biotinyl laminin, biotinyl collagen XVII and biotinyl ascorbyl tetrapeptide. The peptides were produced using liquid-phase and solid-phase synthesis methods. The peptides were conjugated to streptavidin using maleimide or iodoacetyl groups, and the resultant products were characterized BM skin care by SDS-PAGE and immunoblot analysis. The peptides were also tested in a human skin model to assess their effect on the DEJ and BM.
Biotinylated peptides are used in biomedical screening assays that require immobilization onto streptavidin coated beads, membranes, glass slides or microtiter plates. They are also useful in immunoassays where they can bind to antibodies that recognize histone modifications or binding partners. For conjugation to streptavidin, the peptides are first purified by HPLC and then subjected to a chemical modification reaction. The biotin-maleimide reagent (1-biotinamido-4-[4’-(maleimidomethyl)cyclohexanecarboxamido]butane, or BMCC-Biotin) reacts with the maleimide group of lysine residues in the protein, forming a covalent linkage that can be cleaved to release the biotin spacer arm and re-conjugated with other reagents such as iodoacetyl.
Biotinylated nidogen
The basement membrane (BM) is a multilayered extracellular matrix that provides a stable structural environment for the epidermis. It supports cell adhesion, regulates core cellular activities and supports molecular transport. It is composed of the proteins laminins, collagen IVs, nidogens and heparin sulfate proteoglycans. The expression of these components is regulated by epidermal growth factors. The BM is an important interface between the epidermis and the dermis. The loss of BM proteins is associated with skin aging, such as wrinkles.
Nidogen is a multidomain glycoprotein that serves as a bridge between the two most abundant molecules in BMs: laminin and type IV collagen. It also integrates other ECM proteins, such as the proteoglycans heparin sulfate and perlecan, into this specialized extracellular matrix. It is a conserved protein that is present in vertebrates, Drosophila, Caenorhabditis elegans and ascidians. However, phenotypic analysis of mutants deficient in Nidogen has shown that its functions vary between species and tissues.
Nidogen is expressed pericellularly in adipocytes, endothelial cells, chondrocytes, myocytes and nerve cells. It has been shown to play a critical role in the differentiation of these cells. It is involved in the regulation of core cellular functions, including apoptosis and proliferation. It is also involved in cell migration and adherence. In addition, nidogen is an important regulator of the fibronectin/collagen III complex and a mediator of integrin signaling.
Biotinylated laminin
The epithelial layer of the skin is separated from the mesenchymal cells of the stroma by a specialized type of extracellular matrix called the basement membrane (BM). This complex structure consists of a lamina densa, lamina lucida, and large heparin sulfate proteoglycans that form hemidesmosomes. Alterations of the BM have been observed in many types of epithelial neoplasms. They range from local discontinuities to complete loss of heparin fibers and the lamina densa. In addition, alterations of heparan sulfate proteoglycans are also observed in the BM of some keratinocyte carcinomas.
Several BM proteins, including laminins, nidogens, and collagen XVII, are involved in heparin sulfate crosslinking and act as insoluble scaffoldings to support cell growth and differentiation. In addition, these proteins are known to regulate cell migration and adhesion in vitro. Since these proteins are decreased during aging, it is important to identify and develop anti-aging ingredients that can stimulate their expression.
Biotinylated laminins are a good option for this purpose. This peptide derivative is a synthetic analogue of the laminin b2 chain and binds to both the nidogen and heparin sulfate ligands in a 1:1 ratio. It is also highly soluble and has been shown to be effective in promoting the proliferation of cultured keratinocytes and in stimulating the synthesis of collagen XVII. In addition, it has been found to have anti-wrinkle effects in vivo.
Biotinylated collagen XVII
Collagen XVII, a type II transmembrane protein and epithelial adhesion molecule, is proteolytically shed from keratinocytes to generate a soluble form. Shedding is enhanced by phorbol esters and inhibited by metalloprotease inhibitors, including hydroxamates and TIMP-3. Shedding is also stimulated by ADAMs, and expression of the peptide fragments TACE, ADAM-10, and ADAM-9 in keratinocytes correlates with increased shedding. Increasing the activity of these enzymes by transfection with cDNA for their respective products significantly reduces shedding.
To test the effect of peptides on epidermal protein expression, keratinocytes were cultured with different combinations of the three biotinylated peptide derivatives. The peptides demonstrated stimulating activities on the expression of nidogen, laminin, BM skin care shop and collagen XVII in vitro. In addition, peptide complexes showed significant anti-aging effects when applied to ex vivo human skin tissue.
BM proteins are important for cell signaling, migration, differentiation, and proliferation in the dermis. However, their levels decrease with aging, which may contribute to the formation of wrinkles. To address this issue, several researchers have attempted to increase the levels of BM proteins in keratinocytes. This has been done by using peptides that stimulate the synthesis of nidogen and laminin. One such peptide is a pentapeptide that is derived from the b1 chain of laminin, tyrosine-isoleucine-glycine-serine-arginine (YIGSR). The YIGSR pentapeptide was found to promote the synthesis of the full-length laminin 522 and stimulated nidogen and collagen XVII expression in cultured epidermal cells.