sh-Decapeptide-7 is a chemical compound, molecular platform and synthetic protein, identical to a portion of the protein Layilin and capable of providing bioactivity, composed of 10 amino acids linked together including:  glycine, leucine, lysine, phenylalanine, serine, threonine and tyrosine.

Synthetic peptides can be generated as copies of protein fragments by incorporating non-proteinogenic amino acids and modifications to enhance the proteolytic stability of the molecules. Peptides are used in the development of therapeutic drugs (1) for their antimicrobial activity (2), and their bioactive interest (3).

The name describes the structure of the molecule:

• sh - This abbreviation typically stands for "signal peptide" or "synthetic human" suggesting that the peptide is engineered to mimic human biological activities or is designed for specific signaling functions in cosmetic or medical applications.
• Decapeptide  indicates that the molecule is composed of ten amino acids linked together.
• 7 - The numeral represents a specific sequence or variant of the decapeptide, indicating its unique identification or the particular modification in its sequence compared to other similar peptides.

What it is used for and where

sh-Decapeptide-7 is valued in cosmetic formulations for its versatility. It acts as an antioxidant, protecting the skin from free radical damage. As a buffering agent, it helps maintain the optimal pH of the formulation. Its chelating ability allows it to stabilize heavy metals, enhancing product stability and efficacy. As a hair conditioning agent, it improves hair manageability and softness. Its reducing function helps protect hair structure from damage. Lastly, as a skin protector, it strengthens the skin barrier against external aggressors. It is especially effective in anti-aging products and treatments for damaged hair.

Cosmetics - INCI Functions

• Antioxidant agent. Ingredient that counteracts oxidative stress and prevents cell damage. Free radicals, pathological inflammatory processes, reactive nitrogen species and reactive oxygen species are responsible for the ageing process and many diseases caused by oxidation.
• Buffering agent. It is an iingredient that can bring an alkaline or acid solution to a certain pH level and prevent it from changing, in practice a pH stabiliser that can effectively resist instability and pH change.
• Chelating agent. It has the function of preventing unstable reactions and improving the bioavailability of chemical components within a product, and removes calcium and magnesium cations that can cause cloudiness in clear liquids.
• Hair conditioning agent. A significant number of ingredients with specific and targeted purposes may co-exist in hair shampoo formulations: cleansers, conditioners, thickeners, matting agents, sequestering agents, fragrances, preservatives, special additives. However, the indispensable ingredients are the cleansers and conditioners as they are necessary and sufficient for hair cleansing and manageability. The others act as commercial and non-essential auxiliaries such as: appearance, fragrance, colouring, etc. Hair conditioning agents have the task of increasing shine, manageability and volume, and reducing static electricity, especially after treatments such as colouring, ironing, waving, drying and brushing. They are, in practice, dispersants that may contain cationic surfactants, thickeners, emollients, polymers. The typology of hair conditioning agents includes: intensive conditioners, instant conditioners, thickening conditioners, drying conditioners. They can perform their task generally accompanied by other different ingredients.
• Reducing agent. Ingredient that facilitates permanent hair waving by adjusting the pH to an optimal level.
• Skin protectant. It creates a protective barrier on the skin to defend it from harmful substances, irritants, allergens, pathogens that can cause various inflammatory conditions. These products can also improve the natural skin barrier and in most cases more than one is needed to achieve an effective result.

The industrial production process of decapeptides can be divided into several key phases.

• Preparation of solid phase. An appropriate resin is selected as the solid support, which is functionalized with the C-terminal amino acid of the decapeptide.
• Peptide synthesis. Using solid-phase peptide synthesis, amino acids are sequentially added, starting from the C-terminus and proceeding to the N-terminus. Each addition involves deprotecting the terminal amino group followed by coupling of the next amino acid.
• Deprotection. After each amino acid coupling, the protective group is removed and the resin is washed to eliminate unreacted reagents and byproducts.
• Cleavage. Once the peptide chain synthesis is complete, the peptide is cleaved from the resin using a mixture of trifluoroacetic acid (TFA) and other scavenger agents, which help remove side-chain protective groups.
• Purification. The crude peptide is purified using chromatography techniques such as ion-exchange or reverse-phase chromatography to isolate the desired decapeptide.
• Lyophilization. Finally, the decapeptide is lyophilized to remove the solvent and convert it into a powder for more stable storage and distribution.
• Quality control. The purified decapeptide undergoes various tests, including purity determination via HPLC and molecular weight verification via mass spectrometry.

References_____________________________________________________________________

(1) Myšková A, Sýkora D, Kuneš J, Maletínská L. Lipidization as a tool toward peptide therapeutics. Drug Deliv. 2023 Dec;30(1):2284685. doi: 10.1080/10717544.2023.2284685. 

Abstract. Peptides, as potential therapeutics continue to gain importance in the search for active substances for the treatment of numerous human diseases, some of which are, to this day, incurable. As potential therapeutic drugs, peptides have many favorable chemical and pharmacological properties, starting with their great diversity, through their high affinity for binding to all sort of natural receptors, and ending with the various pathways of their breakdown, which produces nothing but amino acids that are nontoxic to the body. Despite these and other advantages, however, they also have their pitfalls. One of these disadvantages is the very low stability of natural peptides. They have a short half-life and tend to be cleared from the organism very quickly. Their instability in the gastrointestinal tract, makes it impossible to administer peptidic drugs orally. To achieve the best pharmacologic effect, it is desirable to look for ways of modifying peptides that enable the use of these substances as pharmaceuticals. There are many ways to modify peptides. Herein we summarize the approaches that are currently in use, including lipidization, PEGylation, glycosylation and others, focusing on lipidization. We describe how individual types of lipidization are achieved and describe their advantages and drawbacks. Peptide modifications are performed with the goal of reaching a longer half-life, reducing immunogenicity and improving bioavailability. In the case of neuropeptides, lipidization aids their activity in the central nervous system after the peripheral administration. At the end of our review, we summarize all lipidized peptide-based drugs that are currently on the market.

(2) Nguyen HLT, Trujillo-Paez JV, Umehara Y, Yue H, Peng G, Kiatsurayanon C, Chieosilapatham P, Song P, Okumura K, Ogawa H, Ikeda S, Niyonsaba F. Role of Antimicrobial Peptides in Skin Barrier Repair in Individuals with Atopic Dermatitis. Int J Mol Sci. 2020 Oct 14;21(20):7607. doi: 10.3390/ijms21207607.

Abstract. Atopic dermatitis (AD) is a common chronic inflammatory skin disease that exhibits a complex interplay of skin barrier disruption and immune dysregulation. Patients with AD are susceptible to cutaneous infections that may progress to complications, including staphylococcal septicemia. Although most studies have focused on filaggrin mutations, the physical barrier and antimicrobial barrier also play critical roles in the pathogenesis of AD. Within the physical barrier, the stratum corneum and tight junctions play the most important roles. The tight junction barrier is involved in the pathogenesis of AD, as structural and functional defects in tight junctions not only disrupt the physical barrier but also contribute to immunological impairments. Furthermore, antimicrobial peptides, such as LL-37, human b-defensins, and S100A7, improve tight junction barrier function. Recent studies elucidating the pathogenesis of AD have led to the development of barrier repair therapy for skin barrier defects in patients with this disease. This review analyzes the association between skin barrier disruption in patients with AD and antimicrobial peptides to determine the effect of these peptides on skin barrier repair and to consider employing antimicrobial peptides in barrier repair strategies as an additional approach for AD management.

(3) Stephanopoulos N. Peptide-Oligonucleotide Hybrid Molecules for Bioactive Nanomaterials. Bioconjug Chem. 2019 Jul 17;30(7):1915-1922. doi: 10.1021/acs.bioconjchem.9b00259. Epub 2019 May 28. PMID: 31082220.

Abstract. Peptides and oligonucleotides are two of the most interesting molecular platforms for making bioactive materials. Peptides provide bioactivity that can mimic that of proteins, whereas oligonucleotides like DNA can be used as scaffolds to immobilize other molecules with nanoscale precision. In this Topical Review, we discuss covalent conjugates of peptides and DNA for creating bioactive materials that can interface with cells. In particular, we focus on two areas. The first is multivalent presentation of peptides on a DNA scaffold, both linear assemblies and more complex nanostructures. The second is the reversible tuning of the extracellular environment-like ligand presentation, stiffness, and hierarchical morphology-in peptide-DNA biomaterials. These examples highlight the potential for creating highly potent materials with benefits not possible with either molecule alone, and we outline a number of future directions and applications for peptide-DNA conjugates.

sh-Decapeptide-13 is a chemical compound, molecular platform and synthetic protein, identical to a portion of the protein Layilin and capable of providing bioactivity, composed of 10 amino acids linked together including:  aspartic acid, cysteine, glutamic acid, glutamine, isoleucine and serine.

Synthetic peptides can be generated as copies of protein fragments by incorporating non-proteinogenic amino acids and modifications to enhance the proteolytic stability of the molecules. Peptides are used in the development of therapeutic drugs (1) for their antimicrobial activity (2), and their bioactive interest (3).

The name describes the structure of the molecule:

• sh - This abbreviation typically stands for "signal peptide" or "synthetic human" suggesting that the peptide is engineered to mimic human biological activities or is designed for specific signaling functions in cosmetic or medical applications.
• Decapeptide  indicates that the molecule is composed of ten amino acids linked together.
• 13 - The numeral represents a specific sequence or variant of the decapeptide, indicating its unique identification or the particular modification in its sequence compared to other similar peptides.

What it is used for and where

sh-Decapeptide-13 is used in hair care cosmetic formulations for its conditioning properties that help to strengthen hair and improve its overall appearance. It promotes scalp health by stimulating the production of vital components that enhance hair elasticity and resilience. It is especially effective in restorative treatments for damaged hair, where it contributes to reducing breakage, increasing shine, and improving manageability.

Cosmetics - INCI Functions

• Skin conditioning agent. It is the mainstay of topical skin treatment as it has the function of restoring, increasing or improving skin tolerance to external factors, including melanocyte tolerance. The most important function of the conditioning agent is to prevent skin dehydration, but the subject is rather complex and involves emollients and humectants that can be added in the formulation.

The industrial production process of decapeptides can be divided into several key phases.

• Preparation of solid phase. An appropriate resin is selected as the solid support, which is functionalized with the C-terminal amino acid of the decapeptide.
• Peptide synthesis. Using solid-phase peptide synthesis, amino acids are sequentially added, starting from the C-terminus and proceeding to the N-terminus. Each addition involves deprotecting the terminal amino group followed by coupling of the next amino acid.
• Deprotection. After each amino acid coupling, the protective group is removed and the resin is washed to eliminate unreacted reagents and byproducts.
• Cleavage. Once the peptide chain synthesis is complete, the peptide is cleaved from the resin using a mixture of trifluoroacetic acid (TFA) and other scavenger agents, which help remove side-chain protective groups.
• Purification. The crude peptide is purified using chromatography techniques such as ion-exchange or reverse-phase chromatography to isolate the desired decapeptide.
• Lyophilization. Finally, the decapeptide is lyophilized to remove the solvent and convert it into a powder for more stable storage and distribution.
• Quality control. The purified decapeptide undergoes various tests, including purity determination via HPLC and molecular weight verification via mass spectrometry.

References_____________________________________________________________________

(1) Myšková A, Sýkora D, Kuneš J, Maletínská L. Lipidization as a tool toward peptide therapeutics. Drug Deliv. 2023 Dec;30(1):2284685. doi: 10.1080/10717544.2023.2284685. 

Abstract. Peptides, as potential therapeutics continue to gain importance in the search for active substances for the treatment of numerous human diseases, some of which are, to this day, incurable. As potential therapeutic drugs, peptides have many favorable chemical and pharmacological properties, starting with their great diversity, through their high affinity for binding to all sort of natural receptors, and ending with the various pathways of their breakdown, which produces nothing but amino acids that are nontoxic to the body. Despite these and other advantages, however, they also have their pitfalls. One of these disadvantages is the very low stability of natural peptides. They have a short half-life and tend to be cleared from the organism very quickly. Their instability in the gastrointestinal tract, makes it impossible to administer peptidic drugs orally. To achieve the best pharmacologic effect, it is desirable to look for ways of modifying peptides that enable the use of these substances as pharmaceuticals. There are many ways to modify peptides. Herein we summarize the approaches that are currently in use, including lipidization, PEGylation, glycosylation and others, focusing on lipidization. We describe how individual types of lipidization are achieved and describe their advantages and drawbacks. Peptide modifications are performed with the goal of reaching a longer half-life, reducing immunogenicity and improving bioavailability. In the case of neuropeptides, lipidization aids their activity in the central nervous system after the peripheral administration. At the end of our review, we summarize all lipidized peptide-based drugs that are currently on the market.

(2) Nguyen HLT, Trujillo-Paez JV, Umehara Y, Yue H, Peng G, Kiatsurayanon C, Chieosilapatham P, Song P, Okumura K, Ogawa H, Ikeda S, Niyonsaba F. Role of Antimicrobial Peptides in Skin Barrier Repair in Individuals with Atopic Dermatitis. Int J Mol Sci. 2020 Oct 14;21(20):7607. doi: 10.3390/ijms21207607.

Abstract. Atopic dermatitis (AD) is a common chronic inflammatory skin disease that exhibits a complex interplay of skin barrier disruption and immune dysregulation. Patients with AD are susceptible to cutaneous infections that may progress to complications, including staphylococcal septicemia. Although most studies have focused on filaggrin mutations, the physical barrier and antimicrobial barrier also play critical roles in the pathogenesis of AD. Within the physical barrier, the stratum corneum and tight junctions play the most important roles. The tight junction barrier is involved in the pathogenesis of AD, as structural and functional defects in tight junctions not only disrupt the physical barrier but also contribute to immunological impairments. Furthermore, antimicrobial peptides, such as LL-37, human b-defensins, and S100A7, improve tight junction barrier function. Recent studies elucidating the pathogenesis of AD have led to the development of barrier repair therapy for skin barrier defects in patients with this disease. This review analyzes the association between skin barrier disruption in patients with AD and antimicrobial peptides to determine the effect of these peptides on skin barrier repair and to consider employing antimicrobial peptides in barrier repair strategies as an additional approach for AD management.

(3) Stephanopoulos N. Peptide-Oligonucleotide Hybrid Molecules for Bioactive Nanomaterials. Bioconjug Chem. 2019 Jul 17;30(7):1915-1922. doi: 10.1021/acs.bioconjchem.9b00259. Epub 2019 May 28. PMID: 31082220.

Abstract. Peptides and oligonucleotides are two of the most interesting molecular platforms for making bioactive materials. Peptides provide bioactivity that can mimic that of proteins, whereas oligonucleotides like DNA can be used as scaffolds to immobilize other molecules with nanoscale precision. In this Topical Review, we discuss covalent conjugates of peptides and DNA for creating bioactive materials that can interface with cells. In particular, we focus on two areas. The first is multivalent presentation of peptides on a DNA scaffold, both linear assemblies and more complex nanostructures. The second is the reversible tuning of the extracellular environment-like ligand presentation, stiffness, and hierarchical morphology-in peptide-DNA biomaterials. These examples highlight the potential for creating highly potent materials with benefits not possible with either molecule alone, and we outline a number of future directions and applications for peptide-DNA conjugates.

sh-Decapeptide-3 is a chemical compound, molecular platform and synthetic protein, identical to a portion of the protein Layilin and capable of providing bioactivity, composed of 10 amino acids linked together including:  arginine, asparagine, glycine, leucine, phenylalanine, serine, tryptophan and tyrosine. 

Synthetic peptides can be generated as copies of protein fragments by incorporating non-proteinogenic amino acids and modifications to enhance the proteolytic stability of the molecules. Peptides are used in the development of therapeutic drugs (1) for their antimicrobial activity (2), and their bioactive interest (3).

The name describes the structure of the molecule:

• sh - This abbreviation typically stands for "signal peptide" or "synthetic human" suggesting that the peptide is engineered to mimic human biological activities or is designed for specific signaling functions in cosmetic or medical applications.
• Decapeptide  indicates that the molecule is composed of ten amino acids linked together.
• 3 - The numeral represents a specific sequence or variant of the decapeptide, indicating its unique identification or the particular modification in its sequence compared to other similar peptides.

What it is used for and where

sh-Decapeptide-3 is effectiveness in boosting skin resilience and structural integrity. By acting directly on skin cells, it intensely stimulates collagen production, essential for a firmer, more youthful appearance. This peptide is particularly effective in treating visible signs of aging, such as deep wrinkles and skin sagging, offering long-lasting benefits and improving the overall texture of the skin.

Cosmetics - INCI Functions

• Skin conditioning agent. It is the mainstay of topical skin treatment as it has the function of restoring, increasing or improving skin tolerance to external factors, including melanocyte tolerance. The most important function of the conditioning agent is to prevent skin dehydration, but the subject is rather complex and involves emollients and humectants that can be added in the formulation.

The industrial production process of decapeptides can be divided into several key phases.

• Preparation of solid phase. An appropriate resin is selected as the solid support, which is functionalized with the C-terminal amino acid of the decapeptide.
• Peptide synthesis. Using solid-phase peptide synthesis, amino acids are sequentially added, starting from the C-terminus and proceeding to the N-terminus. Each addition involves deprotecting the terminal amino group followed by coupling of the next amino acid.
• Deprotection. After each amino acid coupling, the protective group is removed and the resin is washed to eliminate unreacted reagents and byproducts.
• Cleavage. Once the peptide chain synthesis is complete, the peptide is cleaved from the resin using a mixture of trifluoroacetic acid (TFA) and other scavenger agents, which help remove side-chain protective groups.
• Purification. The crude peptide is purified using chromatography techniques such as ion-exchange or reverse-phase chromatography to isolate the desired decapeptide.
• Lyophilization. Finally, the decapeptide is lyophilized to remove the solvent and convert it into a powder for more stable storage and distribution.
• Quality control. The purified decapeptide undergoes various tests, including purity determination via HPLC and molecular weight verification via mass spectrometry.

References_____________________________________________________________________

(1) Myšková A, Sýkora D, Kuneš J, Maletínská L. Lipidization as a tool toward peptide therapeutics. Drug Deliv. 2023 Dec;30(1):2284685. doi: 10.1080/10717544.2023.2284685. 

Abstract. Peptides, as potential therapeutics continue to gain importance in the search for active substances for the treatment of numerous human diseases, some of which are, to this day, incurable. As potential therapeutic drugs, peptides have many favorable chemical and pharmacological properties, starting with their great diversity, through their high affinity for binding to all sort of natural receptors, and ending with the various pathways of their breakdown, which produces nothing but amino acids that are nontoxic to the body. Despite these and other advantages, however, they also have their pitfalls. One of these disadvantages is the very low stability of natural peptides. They have a short half-life and tend to be cleared from the organism very quickly. Their instability in the gastrointestinal tract, makes it impossible to administer peptidic drugs orally. To achieve the best pharmacologic effect, it is desirable to look for ways of modifying peptides that enable the use of these substances as pharmaceuticals. There are many ways to modify peptides. Herein we summarize the approaches that are currently in use, including lipidization, PEGylation, glycosylation and others, focusing on lipidization. We describe how individual types of lipidization are achieved and describe their advantages and drawbacks. Peptide modifications are performed with the goal of reaching a longer half-life, reducing immunogenicity and improving bioavailability. In the case of neuropeptides, lipidization aids their activity in the central nervous system after the peripheral administration. At the end of our review, we summarize all lipidized peptide-based drugs that are currently on the market.

(2) Nguyen HLT, Trujillo-Paez JV, Umehara Y, Yue H, Peng G, Kiatsurayanon C, Chieosilapatham P, Song P, Okumura K, Ogawa H, Ikeda S, Niyonsaba F. Role of Antimicrobial Peptides in Skin Barrier Repair in Individuals with Atopic Dermatitis. Int J Mol Sci. 2020 Oct 14;21(20):7607. doi: 10.3390/ijms21207607.

Abstract. Atopic dermatitis (AD) is a common chronic inflammatory skin disease that exhibits a complex interplay of skin barrier disruption and immune dysregulation. Patients with AD are susceptible to cutaneous infections that may progress to complications, including staphylococcal septicemia. Although most studies have focused on filaggrin mutations, the physical barrier and antimicrobial barrier also play critical roles in the pathogenesis of AD. Within the physical barrier, the stratum corneum and tight junctions play the most important roles. The tight junction barrier is involved in the pathogenesis of AD, as structural and functional defects in tight junctions not only disrupt the physical barrier but also contribute to immunological impairments. Furthermore, antimicrobial peptides, such as LL-37, human b-defensins, and S100A7, improve tight junction barrier function. Recent studies elucidating the pathogenesis of AD have led to the development of barrier repair therapy for skin barrier defects in patients with this disease. This review analyzes the association between skin barrier disruption in patients with AD and antimicrobial peptides to determine the effect of these peptides on skin barrier repair and to consider employing antimicrobial peptides in barrier repair strategies as an additional approach for AD management.

(3) Stephanopoulos N. Peptide-Oligonucleotide Hybrid Molecules for Bioactive Nanomaterials. Bioconjug Chem. 2019 Jul 17;30(7):1915-1922. doi: 10.1021/acs.bioconjchem.9b00259. Epub 2019 May 28. PMID: 31082220.

Abstract. Peptides and oligonucleotides are two of the most interesting molecular platforms for making bioactive materials. Peptides provide bioactivity that can mimic that of proteins, whereas oligonucleotides like DNA can be used as scaffolds to immobilize other molecules with nanoscale precision. In this Topical Review, we discuss covalent conjugates of peptides and DNA for creating bioactive materials that can interface with cells. In particular, we focus on two areas. The first is multivalent presentation of peptides on a DNA scaffold, both linear assemblies and more complex nanostructures. The second is the reversible tuning of the extracellular environment-like ligand presentation, stiffness, and hierarchical morphology-in peptide-DNA biomaterials. These examples highlight the potential for creating highly potent materials with benefits not possible with either molecule alone, and we outline a number of future directions and applications for peptide-DNA conjugates.

sh-Decapeptide-2 is a chemical compound, molecular platform and synthetic protein, identical to a portion of the protein Layilin and capable of providing bioactivity, composed of 10 amino acids linked together including:  arginine, glutamic acid, glutamine, isoleucine, lysine, serine, and tryptophan. 

Synthetic peptides can be generated as copies of protein fragments by incorporating non-proteinogenic amino acids and modifications to enhance the proteolytic stability of the molecules. Peptides are used in the development of therapeutic drugs (1) for their antimicrobial activity (2), and their bioactive interest (3).

The name describes the structure of the molecule:

• sh - This abbreviation typically stands for "signal peptide" or "synthetic human" suggesting that the peptide is engineered to mimic human biological activities or is designed for specific signaling functions in cosmetic or medical applications.
• Decapeptide  indicates that the molecule is composed of ten amino acids linked together.
• 2 - The numeral represents a specific sequence or variant of the decapeptide, indicating its unique identification or the particular modification in its sequence compared to other similar peptides.

What it is used for and where

sh-Decapeptide-2 is a valuable component in advanced cosmetic formulations, acting as a powerful stimulator of skin renewal. It facilitates the repair of damaged tissues and improves skin’s resilience against environmental stresses, reducing aging effects such as loss of elasticity and the formation of fine lines. Ideally incorporated in formulations aimed at treating mature and tired skins

Cosmetics - INCI Functions

• Skin conditioning agent. It is the mainstay of topical skin treatment as it has the function of restoring, increasing or improving skin tolerance to external factors, including melanocyte tolerance. The most important function of the conditioning agent is to prevent skin dehydration, but the subject is rather complex and involves emollients and humectants that can be added in the formulation.

The industrial production process of decapeptides can be divided into several key phases.

• Preparation of solid phase. An appropriate resin is selected as the solid support, which is functionalized with the C-terminal amino acid of the decapeptide.
• Peptide synthesis. Using solid-phase peptide synthesis, amino acids are sequentially added, starting from the C-terminus and proceeding to the N-terminus. Each addition involves deprotecting the terminal amino group followed by coupling of the next amino acid.
• Deprotection. After each amino acid coupling, the protective group is removed and the resin is washed to eliminate unreacted reagents and byproducts.
• Cleavage. Once the peptide chain synthesis is complete, the peptide is cleaved from the resin using a mixture of trifluoroacetic acid (TFA) and other scavenger agents, which help remove side-chain protective groups.
• Purification. The crude peptide is purified using chromatography techniques such as ion-exchange or reverse-phase chromatography to isolate the desired decapeptide.
• Lyophilization. Finally, the decapeptide is lyophilized to remove the solvent and convert it into a powder for more stable storage and distribution.
• Quality control. The purified decapeptide undergoes various tests, including purity determination via HPLC and molecular weight verification via mass spectrometry.

References_____________________________________________________________________

(1) Myšková A, Sýkora D, Kuneš J, Maletínská L. Lipidization as a tool toward peptide therapeutics. Drug Deliv. 2023 Dec;30(1):2284685. doi: 10.1080/10717544.2023.2284685. 

Abstract. Peptides, as potential therapeutics continue to gain importance in the search for active substances for the treatment of numerous human diseases, some of which are, to this day, incurable. As potential therapeutic drugs, peptides have many favorable chemical and pharmacological properties, starting with their great diversity, through their high affinity for binding to all sort of natural receptors, and ending with the various pathways of their breakdown, which produces nothing but amino acids that are nontoxic to the body. Despite these and other advantages, however, they also have their pitfalls. One of these disadvantages is the very low stability of natural peptides. They have a short half-life and tend to be cleared from the organism very quickly. Their instability in the gastrointestinal tract, makes it impossible to administer peptidic drugs orally. To achieve the best pharmacologic effect, it is desirable to look for ways of modifying peptides that enable the use of these substances as pharmaceuticals. There are many ways to modify peptides. Herein we summarize the approaches that are currently in use, including lipidization, PEGylation, glycosylation and others, focusing on lipidization. We describe how individual types of lipidization are achieved and describe their advantages and drawbacks. Peptide modifications are performed with the goal of reaching a longer half-life, reducing immunogenicity and improving bioavailability. In the case of neuropeptides, lipidization aids their activity in the central nervous system after the peripheral administration. At the end of our review, we summarize all lipidized peptide-based drugs that are currently on the market.

(2) Nguyen HLT, Trujillo-Paez JV, Umehara Y, Yue H, Peng G, Kiatsurayanon C, Chieosilapatham P, Song P, Okumura K, Ogawa H, Ikeda S, Niyonsaba F. Role of Antimicrobial Peptides in Skin Barrier Repair in Individuals with Atopic Dermatitis. Int J Mol Sci. 2020 Oct 14;21(20):7607. doi: 10.3390/ijms21207607.

Abstract. Atopic dermatitis (AD) is a common chronic inflammatory skin disease that exhibits a complex interplay of skin barrier disruption and immune dysregulation. Patients with AD are susceptible to cutaneous infections that may progress to complications, including staphylococcal septicemia. Although most studies have focused on filaggrin mutations, the physical barrier and antimicrobial barrier also play critical roles in the pathogenesis of AD. Within the physical barrier, the stratum corneum and tight junctions play the most important roles. The tight junction barrier is involved in the pathogenesis of AD, as structural and functional defects in tight junctions not only disrupt the physical barrier but also contribute to immunological impairments. Furthermore, antimicrobial peptides, such as LL-37, human b-defensins, and S100A7, improve tight junction barrier function. Recent studies elucidating the pathogenesis of AD have led to the development of barrier repair therapy for skin barrier defects in patients with this disease. This review analyzes the association between skin barrier disruption in patients with AD and antimicrobial peptides to determine the effect of these peptides on skin barrier repair and to consider employing antimicrobial peptides in barrier repair strategies as an additional approach for AD management.

(3) Stephanopoulos N. Peptide-Oligonucleotide Hybrid Molecules for Bioactive Nanomaterials. Bioconjug Chem. 2019 Jul 17;30(7):1915-1922. doi: 10.1021/acs.bioconjchem.9b00259. Epub 2019 May 28. PMID: 31082220.

Abstract. Peptides and oligonucleotides are two of the most interesting molecular platforms for making bioactive materials. Peptides provide bioactivity that can mimic that of proteins, whereas oligonucleotides like DNA can be used as scaffolds to immobilize other molecules with nanoscale precision. In this Topical Review, we discuss covalent conjugates of peptides and DNA for creating bioactive materials that can interface with cells. In particular, we focus on two areas. The first is multivalent presentation of peptides on a DNA scaffold, both linear assemblies and more complex nanostructures. The second is the reversible tuning of the extracellular environment-like ligand presentation, stiffness, and hierarchical morphology-in peptide-DNA biomaterials. These examples highlight the potential for creating highly potent materials with benefits not possible with either molecule alone, and we outline a number of future directions and applications for peptide-DNA conjugates.

sh-Decapeptide-1 is a chemical compound, molecular platform and synthetic protein, identical to a portion of the protein Layilin and capable of providing bioactivity, composed of 10 amino acids linked together including:  arginine, glutamic acid, glutamine, isoleucine, lysine, serine, and tryptophan. 

Synthetic peptides can be generated as copies of protein fragments by incorporating non-proteinogenic amino acids and modifications to enhance the proteolytic stability of the molecules. Peptides are used in the development of therapeutic drugs (1) for their antimicrobial activity (2), and their bioactive interest (3).

The name describes the structure of the molecule:

• sh - This abbreviation typically stands for "signal peptide" or "synthetic human" suggesting that the peptide is engineered to mimic human biological activities or is designed for specific signaling functions in cosmetic or medical applications.
• Decapeptide  indicates that the molecule is composed of ten amino acids linked together.
• 1 - The numeral represents a specific sequence or variant of the decapeptide, indicating its unique identification or the particular modification in its sequence compared to other similar peptides.

What it is used for and where

sh-Decapeptide-1 is an active ingredient used in cosmetic formulations for its ability to stimulate collagen production and support cell renewal. This peptide effectively improves skin elasticity and firmness, helping to reduce visible signs of aging such as wrinkles and fine lines. It is commonly used in anti-aging treatments, serums, and creams, providing significant regenerative benefits.

Cosmetics - INCI Functions

• Skin conditioning agent. It is the mainstay of topical skin treatment as it has the function of restoring, increasing or improving skin tolerance to external factors, including melanocyte tolerance. The most important function of the conditioning agent is to prevent skin dehydration, but the subject is rather complex and involves emollients and humectants that can be added in the formulation.

The industrial production process of decapeptides can be divided into several key phases.

• Preparation of solid phase. An appropriate resin is selected as the solid support, which is functionalized with the C-terminal amino acid of the decapeptide.
• Peptide synthesis. Using solid-phase peptide synthesis, amino acids are sequentially added, starting from the C-terminus and proceeding to the N-terminus. Each addition involves deprotecting the terminal amino group followed by coupling of the next amino acid.
• Deprotection. After each amino acid coupling, the protective group is removed and the resin is washed to eliminate unreacted reagents and byproducts.
• Cleavage. Once the peptide chain synthesis is complete, the peptide is cleaved from the resin using a mixture of trifluoroacetic acid (TFA) and other scavenger agents, which help remove side-chain protective groups.
• Purification. The crude peptide is purified using chromatography techniques such as ion-exchange or reverse-phase chromatography to isolate the desired decapeptide.
• Lyophilization. Finally, the decapeptide is lyophilized to remove the solvent and convert it into a powder for more stable storage and distribution.
• Quality control. The purified decapeptide undergoes various tests, including purity determination via HPLC and molecular weight verification via mass spectrometry.

References_____________________________________________________________________

(1) Myšková A, Sýkora D, Kuneš J, Maletínská L. Lipidization as a tool toward peptide therapeutics. Drug Deliv. 2023 Dec;30(1):2284685. doi: 10.1080/10717544.2023.2284685. 

Abstract. Peptides, as potential therapeutics continue to gain importance in the search for active substances for the treatment of numerous human diseases, some of which are, to this day, incurable. As potential therapeutic drugs, peptides have many favorable chemical and pharmacological properties, starting with their great diversity, through their high affinity for binding to all sort of natural receptors, and ending with the various pathways of their breakdown, which produces nothing but amino acids that are nontoxic to the body. Despite these and other advantages, however, they also have their pitfalls. One of these disadvantages is the very low stability of natural peptides. They have a short half-life and tend to be cleared from the organism very quickly. Their instability in the gastrointestinal tract, makes it impossible to administer peptidic drugs orally. To achieve the best pharmacologic effect, it is desirable to look for ways of modifying peptides that enable the use of these substances as pharmaceuticals. There are many ways to modify peptides. Herein we summarize the approaches that are currently in use, including lipidization, PEGylation, glycosylation and others, focusing on lipidization. We describe how individual types of lipidization are achieved and describe their advantages and drawbacks. Peptide modifications are performed with the goal of reaching a longer half-life, reducing immunogenicity and improving bioavailability. In the case of neuropeptides, lipidization aids their activity in the central nervous system after the peripheral administration. At the end of our review, we summarize all lipidized peptide-based drugs that are currently on the market.

(2) Nguyen HLT, Trujillo-Paez JV, Umehara Y, Yue H, Peng G, Kiatsurayanon C, Chieosilapatham P, Song P, Okumura K, Ogawa H, Ikeda S, Niyonsaba F. Role of Antimicrobial Peptides in Skin Barrier Repair in Individuals with Atopic Dermatitis. Int J Mol Sci. 2020 Oct 14;21(20):7607. doi: 10.3390/ijms21207607.

Abstract. Atopic dermatitis (AD) is a common chronic inflammatory skin disease that exhibits a complex interplay of skin barrier disruption and immune dysregulation. Patients with AD are susceptible to cutaneous infections that may progress to complications, including staphylococcal septicemia. Although most studies have focused on filaggrin mutations, the physical barrier and antimicrobial barrier also play critical roles in the pathogenesis of AD. Within the physical barrier, the stratum corneum and tight junctions play the most important roles. The tight junction barrier is involved in the pathogenesis of AD, as structural and functional defects in tight junctions not only disrupt the physical barrier but also contribute to immunological impairments. Furthermore, antimicrobial peptides, such as LL-37, human b-defensins, and S100A7, improve tight junction barrier function. Recent studies elucidating the pathogenesis of AD have led to the development of barrier repair therapy for skin barrier defects in patients with this disease. This review analyzes the association between skin barrier disruption in patients with AD and antimicrobial peptides to determine the effect of these peptides on skin barrier repair and to consider employing antimicrobial peptides in barrier repair strategies as an additional approach for AD management.

(3) Stephanopoulos N. Peptide-Oligonucleotide Hybrid Molecules for Bioactive Nanomaterials. Bioconjug Chem. 2019 Jul 17;30(7):1915-1922. doi: 10.1021/acs.bioconjchem.9b00259. Epub 2019 May 28. PMID: 31082220.

Abstract. Peptides and oligonucleotides are two of the most interesting molecular platforms for making bioactive materials. Peptides provide bioactivity that can mimic that of proteins, whereas oligonucleotides like DNA can be used as scaffolds to immobilize other molecules with nanoscale precision. In this Topical Review, we discuss covalent conjugates of peptides and DNA for creating bioactive materials that can interface with cells. In particular, we focus on two areas. The first is multivalent presentation of peptides on a DNA scaffold, both linear assemblies and more complex nanostructures. The second is the reversible tuning of the extracellular environment-like ligand presentation, stiffness, and hierarchical morphology-in peptide-DNA biomaterials. These examples highlight the potential for creating highly potent materials with benefits not possible with either molecule alone, and we outline a number of future directions and applications for peptide-DNA conjugates.

Sodium lauryl oxyethyl sulfate (Sodium Laureth sulfate or SLES), is a chemical compound and belongs to a group of salts of sulfated ethoxylated alcohols. It occurs in liquid form or clear transparent slightly yellow gel or white fine powder.

The name describes the structure of the molecule:

• Sodium is the sodium ion (Na+), an alkaline metal.
• Laureth is a term used in the cosmetics industry for a mixture of polyethylene glycol (PEG) and lauryl alcohol. The term 'laureth' is a contraction of 'lauryl ether', where 'lauryl' refers to the 12-carbon lauryl group derived from lauric acid, a medium-chain fatty acid found in coconut oil and palm kernel or palm oil.
• sulphate is a sulphate group (SO4-2-), a sulphur atom bonded to four oxygen atoms and having a negative charge.

The synthesis process takes place in different steps:

• Extraction.The raw materials are lauryl alcohol and ethylene oxide. Lauryl alcohol is typically derived from coconut or palm oil, while ethylene oxide is a petrochemical product.
• Ethoxylation. Lauryl alcohol is reacted with ethylene oxide in a process called ethoxylation. This reaction is catalysed by a base, usually a strong alkali such as potassium hydroxide. The term 'eth' in 'laureth' indicates that ethylene oxide has been added.
• Sulphonation. Ethoxylated alcohol is reacted with sulphur trioxide (SO3) to produce a sulphate.
• Neutralisation. The sulphate is neutralised with sodium hydroxide (NaOH) to produce sodium sulphate.
• Purification. The resulting product is purified through distillation and filtration to remove any unreacted materials and by-products.
• Quality control. The final product is tested to ensure that it meets quality standards.

SLES (Sodium laureth sulfate) must not be confused with SLS  because, although both are similar and have sulphuric acid and lauryl alcohol as their formula, differ in chemical properties. In SLES, which is less aggressive than SLS but is ethoxylated (obtained from ethylene oxide), it is not uncommon to find in SLES ethylene oxide and 1,4-dioxane residues, chemical compounds that are considered carcinogenic.

The term 'eth' refers to the ethoxylation reaction with ethylene oxide after which residues of ethylene oxide and 1,4-dioxane, chemical compounds considered carcinogenic, may remain. The degree of safety therefore depends on the degree of purity of the compound obtained. No manufacturer appears to provide this information on the label, at least as of the date of this review.

A preliminary remark must be made about synthetic surfactants, which can be divided into four groups:

• Anionic (SLS, ALS, SLES), which solubilises well with lipid monolayers but not with lipid bilayers model of liposomes or cytotoxicity tests towards cultured skin cells
• Nonionic amphoteric (CAPB), which solubilises well with both mono- and bilayers
• Biotensioactive (SAP), which penetrates monolayers at 1% dry mass without solubilisation, and probably penetrates bilayers, increasing their size (without solubilisation).

What it is for and where

Chemical intermediate, anionic surfactant, densifying and foaming agent, with good solvency, wide compatibility, strong resistance to hard water, high biodegradation and relatively low skin and eye irritation.

Sodium Laureth sulfate is used in cosmetics, in liquid detergents, such as hair and bath shampoos, dishwashing detergents, toothpastes, bubble bath and hand washing, soap etc.. In chromatography as a reagent, it has excellent properties as a solvent. In printing and dyeing industry, oil and leather, textile,,, it can be used as lubricant, dyeing agent, cleaner, foaming agent and degreasing agent.

Cosmetics

Cleansing agent. Ingredient that cleanses skin without exploiting the surface-active properties that produce a lowering of the surface tension of the stratum corneum. 

Foaming.  Its function is to introduce gas bubbles into the water for a purely aesthetic factor, which does not affect the cleaning process, but only satisfies the commercial aspect of the detergent by helping to spread the detergent. This helps in the commercial success of a cleansing formulation. Since sebum has an inhibiting action on the bubble, more foam is produced in the second shampoo. In practice, it creates many small bubbles of air or other gases within a small volume of liquid, changing the surface tension of the liquid.

Surfactant - Cleansing agent. Cosmetic products used to cleanse the skin utilise the surface-active action that produces a lowering of the surface tension of the stratum corneum, facilitating the removal of dirt and impurities. 

Surfactant - Emulsifying agent. Emulsions are thermodynamically unstable and are used to soothe or soften the skin and emulsify, so they need a specific, stabilising ingredient. This ingredient forms a film, lowers the surface tension and makes two immiscible liquids miscible. A very important factor affecting the stability of the emulsion is the amount of the emulsifying agent. Emulsifiers have the property of reducing the oil/water or water/oil interfacial tension, improving the stability of the emulsion and also directly influencing the stability, sensory properties and surface tension of sunscreens by modulating the filmometric performance.

Safety

It is used in mild soaps and shampoos. However, it can cause eye irritation if used in large quantities. Since it is not mandatory to indicate the percentage or quantity of the chemical on labels, it is still difficult to know how much Sodium Laureth sulfate is in the product. The scientific literature that has dealt with this chemical compound for decades has concluded in favour of a recognition of the irritant properties of Sodium lauryl ether sulphate. Since it is not uncommon for ethylene oxide (1) and 1,4-Dioxane, a synthetic cyclic ether traditionally used as a stabiliser (2), to be found in this chemical compound during the production process, the IARC (International Agency for Research on Cancer ) warns that ethylene oxide is carcinogenic to humans (3) and 1,4-Dioxane is potentially carcinogenic to humans (4). The real problem is that no manufacturer declares SLES as free of these two compounds on the label. So we cannot know if and how much ethylene oxide and 1,4-dioxane are present in the product we have purchased. In addition, 1,4-dioxane does not degrade easily and is therefore considered to be a water pollutant that must be removed using special techniques (5).

From the above, a rather negative picture emerges for SLES, and my opinion is to be cautious and not to buy products containing SLES unless the absence of ethylene oxide and 1,4-dioxane is clearly indicated.

 It is also important not to mistake the acronyms SLES (Sodium lauryl polyoxyethylene ether sulfate Sodium Laureth Sulfate) with SLS (Sodium lauryl sulfate), also a surfactant but much less aggressive.

The most relevant studies on this chemical compound have been selected with a summary of their contents:

Sodium Laureth sulfate studies

Typical characteristics of the commercial product Sodium lauryl polyoxyethylene ether sulfate Sodium Laureth Sulfate (SLES)

PSA	84.04000
LogP	4.48150
Safety

• Molecular Formula: C₁₄H₂₉NaO₅S
• Molecular Weight: 332.431 g/mol
• CAS: 15826-16-1
• EC Number: 239-925-1 
• UNII 410Q7WN1BX
• DSSTox Substance ID: DTXSID2029298    DTXSID70274019
• MDL number  
• PubChem Substance ID 
• InChI=1S/C14H30O5S.Na/c1-2-3-4-5-6-7-8-9-10-11-12-18-13-14-19-20(15,16)17;/h2-14H2,1H3,(H,15,16,17);/q;+1/p-1  
• InChl Key      ASEFUFIKYOCPIJ-UHFFFAOYSA-M
• SMILES    CCCCCCCCCCCCOCCOS(=O)(=O)[O-].[Na+]
• IUPAC   sodium;2-dodecoxyethyl sulfate
• RTECS    KK7890000

Synonyms:

• SLES
• Sodium dodecylpoly(oxyethylene) sulfate
• Sodium Laureth sulfate

 References______________________________________________________________________

(1) Vleugels LF, Pollet J, Tuinier R. Polycation-sodium lauryl ether sulfate-type surfactant complexes: influence of ethylene oxide length. J Phys Chem B. 2015 May 21;119(20):6338-47. doi: 10.1021/acs.jpcb.5b02043.

(2) Black RE, Hurley FJ, Havery DC. Occurrence of 1,4-dioxane in cosmetic raw materials and finished cosmetic products. J AOAC Int. 2001 May-Jun;84(3):666-70.

(3) Ethylene oxide. IARC Monogr Eval Carcinog Risks Hum. 1994;60:73-159. 

(4) 1,4-Dioxane. IARC Monogr Eval Carcinog Risks Hum. 1999;71 Pt 2(PT 2):589-602.

Wilbur S, Jones D, Risher JF, Crawford J, Tencza B, Llados F, Diamond GL, Citra M, Osier MR, Lockwood LO. Toxicological Profile for 1,4-Dioxane. Atlanta (GA): Agency for Toxic Substances and Disease Registry (US); 2012 Apr.

(5) Scaratti G, De Noni Júnior A, José HJ, de Fatima Peralta Muniz Moreira R. 1,4-Dioxane removal from water and membrane fouling elimination using CuO-coated ceramic membrane coupled with ozone. Environ Sci Pollut Res Int. 2020 Jun;27(18):22144-22154. doi: 10.1007/s11356-019-07497-6.

Dipeptide-45  is a chemical compound, a synthetic peptide, and a molecule composed of asparagine and serine.

Peptides are substances consisting of two or more amino acids linked together by a linear chain. Synthetic peptides can be generated as copies of protein fragments by incorporating non-proteinogenic amino acids and modified so as to also increase the proteolytic stability of the molecules. Dipeptides are composed of two amino acids connected by a peptide bond.

What it is used for and where

Dipeptide-45 is a synthetic peptide commonly included in skincare products due to its moisturizing and regenerative properties. It helps stimulate collagen production, improving skin elasticity and reducing the appearance of wrinkles and fine lines. Additionally, it strengthens the skin barrier, making the skin more resistant to environmental damage. 

Cosmetics

• Skin conditioning agent. It is the mainstay of topical skin treatment as it has the function of restoring, increasing or improving skin tolerance to external factors, including melanocyte tolerance. The most important function of the conditioning agent is to prevent skin dehydration, but the subject is rather complex and involves emollients and humectants that can be added in the formulation.

Medical

Tripeptides and dipeptides have proven useful in biomedical applications (1) and for sensitive skin (2) and have demonstrated antioxidant activity (3).

References_____________________________________________________________________

(1) Santos S, Torcato I, Castanho MA. Biomedical applications of dipeptides and tripeptides. Biopolymers. 2012;98(4):288-93. doi: 10.1002/bip.22067. PMID: 23193593.

Abstract. Peptides regulate many physiological processes, acting at some sites as endocrine or paracrine signals and at others as neurotransmitters or growth factors, for instance. These molecules represent a major evolution in medical and industrial fields, as it is becoming mandatory to design and exploit molecules that do not necessarily fit the description of classical drug classes. The list of peptides with potential biomedical applications is huge and is growing each year. These biomedical applications range from uses as drugs to flavor-active peptides as ingredients in natural health products, nutraceuticals and functional foods. Among the peptide family, dipeptides and tripeptides are very appealing for drug discovery and development because of their cost-effectiveness, possibility of oral administration, and simplicity to perform molecular structural and quantitative structure-activity studies. Our objective is to review different actual and future uses of dipeptides and tripeptides as well as the major advances and obstacles in this growing area.

(2) Resende DISP, Ferreira MS, Sousa-Lobo JM, Sousa E, Almeida IF. Usage of Synthetic Peptides in Cosmetics for Sensitive Skin. Pharmaceuticals (Basel). 2021 Jul 21;14(8):702. doi: 10.3390/ph14080702. 

 Abstract. Sensitive skin is characterized by symptoms of discomfort when exposed to environmental factors. Peptides are used in cosmetics for sensitive skin and stand out as active ingredients for their ability to interact with skin cells by multiple mechanisms, high potency at low dosage and the ability to penetrate the stratum corneum. This study aimed to analyze the composition of 88 facial cosmetics for sensitive skin from multinational brands regarding usage of peptides, reviewing their synthetic pathways and the scientific evidence that supports their efficacy. Peptides were found in 17% of the products analyzed, namely: acetyl dipeptide-1 cetyl ester, palmitoyl tripeptide-8, acetyl tetrapeptide-15, palmitoyl tripeptide-5, acetyl hexapeptide-49, palmitoyl tetrapeptide-7 and palmitoyl oligopeptide. Three out of seven peptides have a neurotransmitter-inhibiting mechanism of action, while another three are signal peptides. Only five peptides present evidence supporting their use in sensitive skin, with only one clinical study including volunteers having this condition. Noteworthy, the available data is mostly found in patents and supplier brochures, and not in randomized placebo-controlled studies. Peptides are useful active ingredients in cosmetics for sensitive skin. Knowing their efficacy and synthetic pathways provides meaningful insight for the development of new and more effective ingredients.

(3) Ozawa H, Miyazawa T, Burdeos GC, Miyazawa T. Biological Functions of Antioxidant Dipeptides. J Nutr Sci Vitaminol (Tokyo). 2022;68(3):162-171. doi: 10.3177/jnsv.68.162. PMID: 35768247.

Abstract. In the history of modern nutritional science, understanding antioxidants is one of the major topics. In many cases, food-derived antioxidants have π conjugate or thiol group in their molecular structures because π conjugate stabilizes radical by its delocalization and two thiol groups form a disulfide bond in its antioxidative process. In recent years, antioxidant peptides have received much attention because for their ability to scavenge free radicals, inhibition of lipid peroxidation, chelation of transition metal ions, as well as their additional nutritional value. Among them, dipeptides are attracting much interest as post-amino acids, which have residues in common with amino acids, but also have different physiological properties and functions from those of amino acids. Especially, dipeptides containing moieties of several amino acid (tryptophan, tyrosine, histidine, cysteine, and methionine) possess potent antioxidant activity. This review summarizes previous details of structural property, radical scavenging activity, and biological activity of antioxidant dipeptide. Hopefully, this review will help provide a new insight into the study of the biological functions of antioxidant dipeptides.