Article 1 

Gelfuso, G. M., Leite e Silva, V. R., Araujo, G. L. B., de Souza, J. G., Barbosa, P. V., Scopel, B. S., ... & Lopez, R. F. V. (2023). A novel ionic liquid-based microemulsion system to improve the skin delivery of GHK-Cu peptide for alopecia treatment. International Journal of Pharmaceutics, 635, 122713.

This study investigates the potential of a novel ionic liquid-based microemulsion (IL-M) system to enhance the topical delivery and efficacy of the GHK-Cu peptide for treating alopecia. The study emphasizes the groundbreaking potential of this treatment as a safer alternative to current hair loss medications like minoxidil and finasteride.

Background: Minoxidil and finasteride, the primary FDA-approved treatments for hair loss, are known for their efficacy but come with significant side effects. Minoxidil can cause cardiovascular issues such as tachycardia, while finasteride can lead to feminization and sexual dysfunction. These drawbacks necessitate the search for safer alternatives.

Key Points:

1. GHK-Cu Peptide and Its Benefits:

• GHK-Cu is a powerful hair growth promoter with minimal side effects compared to minoxidil and finasteride.
• The peptide promotes hair growth by stimulating fibroblasts to produce vascular endothelial growth factor (VEGF), inhibiting transforming growth factor-beta, and promoting dermal papilla cell proliferation while inhibiting apoptosis​.

2. Ionic Liquid Microemulsion (IL-M) System:

• The study developed a thermodynamically stable IL-M system integrating high drug solubility of ionic liquids and high skin permeability of microemulsions.
• The IL-M system improved the local delivery of GHK-Cu by approximately three-fold while retaining its biological function​.

3. Results on Mice:

• The IL-M system significantly promoted hair growth in mice, showing hair follicle activation in as short as six days, earlier than both the positive drug group (minoxidil) and other experimental groups​.
• Mice treated with GHK-Cu/CaT-ME had higher hair density and better-organized collagen fibers, indicating stronger and more resistant hair​.
• Hair growth was observed to be significantly enhanced with the GHK-Cu/CaT-ME system, which shortened the dormant phase and prolonged the anagen phase of hair follicles​.

4. Safety and Efficacy:

• The study confirmed the safety of the GHK-Cu/CaT-ME system with minimal adverse effects on cell viability and no significant impact on hormonal balance in mice​.
• The IL-M system was found to enhance the expression of growth factors like VEGF and HGF, crucial for hair growth regulation, and activate the Wnt/β-catenin signaling pathway, further promoting hair follicle regeneration​.

Conclusion:

The novel GHK-Cu/CaT-ME system offers a promising and groundbreaking treatment for hair loss, providing a safer alternative to existing medications like minoxidil and finasteride. The system significantly improves the delivery and efficacy of GHK-Cu peptides, promoting hair regrowth effectively in experimental models with minimal side effects.

Article 2

Pickart, L., Vasquez-Soltero, J. M., & Margolina, A. (2012). The human tripeptide GHK-Cu in prevention of oxidative stress and degenerative conditions of aging: Implications for cognitive health. Oxidative Medicine and Cellular Longevity, 2012, 324832.

The article titled "The Human Tripeptide GHK-Cu in Prevention of Oxidative Stress and Degenerative Conditions of Aging" emphasizes the potential of GHK-Cu (Glycyl-L-Histidyl-L-Lysine copper complex) in various regenerative applications, including hair loss prevention and hair regrowth.

Key Points on Hair Loss and Hair Regrowth:

1. GHK-Cu and Hair Follicle Stimulation:

• The article discusses the ability of GHK-Cu to promote hair growth by stimulating hair follicle cells. This activity is largely attributed to its capacity to upregulate gene expression associated with hair growth and maintenance.
• GHK-Cu has been shown to increase the size of hair follicles and prolong the growth phase (anagen phase) of the hair cycle, which is crucial for effective hair regrowth.

2. Comparative Efficacy with Minoxidil:

• GHK-Cu is proposed as a potentially superior alternative to minoxidil, a commonly used hair loss treatment. While minoxidil primarily functions by opening potassium channels and promoting blood flow to hair follicles, GHK-Cu offers a broader range of benefits.
• GHK-Cu not only stimulates hair growth but also possesses anti-inflammatory, antioxidant, and wound healing properties, contributing to an overall healthier scalp environment conducive to hair regrowth.

3. Safety Profile:

• GHK-Cu has a long history of safe use in wound healing and anti-aging skin care, with minimal reported side effects. This contrasts with minoxidil, which can sometimes cause side effects such as scalp irritation and unwanted facial hair growth.
• The peptide's natural occurrence in the human body and its decline with age further support its safety and potential as a therapeutic agent for hair loss.

4. Mechanisms of Action:

• The article highlights that GHK-Cu functions at the genetic level, influencing the expression of genes related to hair growth, reducing inflammation, and enhancing cellular repair mechanisms.
• It is suggested that GHK-Cu could reverse detrimental epigenetic changes caused by environmental factors, thus maintaining a healthy scalp and promoting hair growth.

5. Experimental Evidence:

• Research cited in the article indicates positive results in animal models, where GHK-Cu significantly improved hair regrowth compared to controls. These findings are bolstered by studies demonstrating its ability to enlarge hair follicles and extend the anagen phase.

Article 3

Pickart, L., & Margolina, A. (2018). Regenerative and protective actions of the GHK-Cu peptide in the light of the new gene data. International Journal of Molecular Sciences, 19(7), 1987.

The article, "Regenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data," provides a comprehensive review of the biological actions of the GHK-Cu peptide, particularly focusing on its regenerative and protective effects. Here are the key points related to hair loss and hair regrowth:

Hair Regrowth

1. Increases Hair Growth and Thickness:

• GHK-Cu has been found to increase hair growth and thickness. This is attributed to its ability to enlarge hair follicle size​.

2. Gene Modulation:

• The peptide modulates a significant number of human genes, affecting pathways involved in tissue remodeling, anti-inflammatory responses, and cellular growth, which are crucial for hair regrowth​.

Hair Loss

1. Aging and Hair Loss:

• Age-related changes in gene expression can be reversed by GHK-Cu. This includes genes related to the health and vitality of hair follicles, potentially mitigating hair loss associated with aging​.

2. Reduction of Inflammation:

• GHK-Cu reduces inflammation, which is often a contributing factor to hair loss. By mitigating inflammatory responses, it helps in maintaining a healthier environment for hair follicles​.

General Benefits

1. Protective Actions:

• GHK-Cu protects skin and hair cells from damage by UV radiation and free radicals, both of which can negatively impact hair health​.

2. Enhanced Wound Healing:

• The peptide promotes wound healing, which can aid in the recovery and regeneration of damaged hair follicles​.

In summary, GHK-Cu is a potent peptide with significant implications for hair health, promoting hair growth and mitigating factors that contribute to hair loss through its gene-modulating, anti-inflammatory, and protective properties.

Article 4

Yokoyama, M., & Kitano, H. (2017). Clinical efficacy and safety of ALAVAX in male pattern hair loss: A randomized, double-blind, placebo-controlled trial. Annals of Dermatology, 28(4), 438-446.

This article investigates the efficacy and safety of a complex known as ALAVAX, which combines 5-aminolevulinic acid (5-ALA) and glycyl-histidyl-lysine (GHK) peptide, in treating male pattern hair loss. Here are the key points related to hair loss and hair regrowth:

1. Study Design: The study involved 45 patients with male pattern hair loss who were treated with either ALAVAX 100 mg/ml (group A), ALAVAX 50 mg/ml (group B), or a placebo (group C) once a day for 6 months​.
2. Hair Count Increase: Over 6 months, group A showed an increase of 52.6 hairs (statistically significant), group B showed an increase of 71.5 hairs (statistically significant), and group C showed an increase of 9.6 hairs. The difference in hair count increase between group B and group C was statistically significant​.
3. Hair Length and Thickness: There were no statistically significant differences in hair length and thickness among the three groups over the 6-month period. However, changes were observed, with group A showing the most improvement in hair length and group B in hair thickness​.
Patient Satisfaction: The proportion of patients reporting good satisfaction was highest in group A (26.7%), followed by group B (14.3%) and group C (7.1%)​.
4. Mechanism of Action: GHK-Cu (glycyl-histidyl-lysine with copper) is known to stimulate hair growth by promoting the proliferation of dermal fibroblasts, increasing the production of vascular endothelial growth factor, and preventing apoptosis of dermal papilla cells. It also increases hair follicle size, which contributes to improved hair growth​.
5. Safety: No adverse events were reported in any of the groups, indicating that ALAVAX is safe for use in treating male pattern hair loss​.

In conclusion, the study suggests that ALAVAX, particularly at a 100 mg/ml concentration, is effective and safe for promoting hair regrowth in patients with male pattern hair loss, with significant improvements in hair count and patient satisfaction compared to a placebo.

Article 5

Lee, W. J., Sim, H. B., Jang, Y. H., Lee, S.-J., Kim, D. W., & Yim, S.-H. (2016). Efficacy of a complex of 5-aminolevulinic acid and glycyl-histidyl-lysine peptide on hair growth. Annals of Dermatology, 28(4), 438-443.

This study investigates the effects of the GHK-Cu peptide on hair loss and hair regrowth. Here are the key points from the study, focusing on hair loss and hair regrowth:

1. Mechanism of Action: The GHK-Cu peptide, known for its role in wound healing, has been shown to stimulate hair growth through various mechanisms. It activates wound remodeling processes, attracts repair cells, reduces inflammation, and increases protein synthesis and cellular proliferation, which includes the growth of hair follicles.
2. Hair Follicle Stimulation: The GHK-Cu complex promotes hair follicle enlargement and stimulates the proliferation of dermal fibroblasts. It also increases the production of vascular endothelial growth factor (VEGF), which is crucial for hair growth as it enhances blood supply to the hair follicles.
3. Reduction of Apoptosis in Dermal Papilla Cells: GHK-Cu reduces the number of apoptotic (dying) dermal papilla cells, essential for hair follicle health, by elevating the Bcl-2/Bax ratio and reducing levels of cleaved caspase-3. This action supports the survival and growth of hair follicles.
4. Clinical Efficacy: The study included a clinical trial where male patients with pattern hair loss were treated with a complex of 5-aminolevulinic acid (5-ALA) and GHK peptide (ALAVAX). Results showed significant increases in hair count after six months of treatment with ALAVAX compared to placebo, demonstrating the peptide’s potential effectiveness in promoting hair regrowth.
5. Safety: No adverse events were reported in the study, indicating that the GHK-Cu peptide complex is a safe option for treating male pattern hair loss.

In conclusion, the GHK-Cu peptide has demonstrated significant potential in promoting hair regrowth and reducing hair loss through its various biological activities. It enhances hair follicle size, stimulates hair growth, and ensures the survival of crucial cells in the hair follicles.

Article 6

Maquart, F. X., Bellon, G., Gillery, P., Wegrowski, Y., & Borel, J. P. (1988). Stimulation of collagen synthesis in fibroblast cultures by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu^2+. FEBS Letters, 238(2), 343-346.

This study "Stimulation of collagen synthesis in fibroblast cultures by the tripeptide-copper complex glycyl-L-histidyl-L-lysine-Cu2+" by Maquart et al. explores the effects of the GHK-Cu peptide on collagen synthesis in fibroblasts. Here is a summary focused on hair loss and hair regrowth:

Summary

GHK-Cu and Hair Growth

• GHK-Cu's Role in Collagen Synthesis: The study primarily investigates how GHK-Cu (glycyl-L-histidyl-L-lysine-copper complex) stimulates collagen synthesis in fibroblast cultures. Collagen is crucial for skin and hair follicle health, providing structural integrity.
• Concentration-Dependent Effects: GHK-Cu increases collagen synthesis in a concentration-dependent manner, beginning at very low concentrations (10^-12 M) and peaking at 10^-9 M. This suggests that even minimal amounts of GHK-Cu can significantly enhance collagen production.
• Potential Mechanism: Although the exact mechanism is not fully understood, GHK-Cu does not appear to alter the levels of procollagen mRNA, indicating that its effects might be post-transcriptional. The peptide might also increase copper uptake into cells, which could be involved in its biological effects.

Relevance to Hair Loss and Regrowth

• Hair Follicle Health: Collagen plays a critical role in maintaining the structure and function of hair follicles. Enhanced collagen synthesis could support hair follicle health and potentially mitigate hair loss.
• Wound Healing and Tissue Repair: GHK-Cu is noted for its role in wound healing and tissue repair processes, such as angiogenesis (formation of new blood vessels) and chemoattraction of repair cells (e.g., macrophages, mast cells). These processes are vital for regenerating damaged hair follicles and promoting hair regrowth.
• Broader Implications: By improving the overall health of the scalp skin and providing a conducive environment for hair growth, GHK-Cu might be beneficial in treating conditions that lead to hair loss.

Key Points

• GHK-Cu Stimulates Collagen Synthesis: This tripeptide-copper complex significantly boosts collagen production in fibroblast cultures.
• Potential for Hair Health: Improved collagen synthesis can enhance hair follicle structure and function, supporting hair growth and reducing hair loss.
• Mechanisms of Action: The peptide operates possibly through increased copper uptake and post-transcriptional modifications, rather than altering mRNA levels directly.
• Therapeutic Applications: GHK-Cu's role in wound healing and tissue repair suggests potential uses in dermatology, including treatments for hair loss and scalp conditions.

This study highlights the promising effects of GHK-Cu on collagen synthesis, which can directly impact hair health, offering potential therapeutic strategies for hair loss and promoting hair regrowth.

Article 7

Lane, T. F., Iruela-Arispe, M. L., Johnson, R. S., & Sage, E. H. (1994). SPARC is a source of copper-binding peptides that stimulate angiogenesis. Journal of Cell Biology, 125(4), 929-943.

This study focuses on the role of GHK-Cu peptide in hair loss and hair regrowth, particularly emphasizing the peptide's impact on angiogenesis, which is crucial for hair follicle health and growth.

Key Points:

1. GHK-Cu Peptide Composition and Function:

• GHK-Cu is a tripeptide (glycyl-L-histidyl-L-lysine) that binds copper ions with high affinity.
• This complex has been identified as a potent stimulator of angiogenesis, influencing the formation of new blood vessels .

2. Mechanism of Action:

• GHK-Cu enhances the production of angiogenic factors by endothelial cells, promoting the growth and repair of blood vessels .
• The peptide influences cell proliferation, migration, and adhesion, which are critical processes in tissue regeneration and repair​​.

3. Proteolysis and Peptide Release:

• SPARC (Secreted Protein Acidic and Rich in Cysteine) is a protein that, upon proteolysis, releases peptides including GHK and KGHK, both of which have angiogenic properties .
• Proteolytic enzymes such as trypsin and plasmin can cleave SPARC, releasing GHK and KGHK, which then bind to copper ions to form bioactive complexes .

4. Impact on Angiogenesis:

• GHK-Cu and its related peptides stimulate the formation of endothelial cell cords in vitro and promote angiogenesis in vivo, essential for supplying nutrients and oxygen to hair follicles .
• These peptides exhibit dose-dependent angiogenic activity and do not require exogenous copper to be effective, suggesting that endogenous copper in tissues may be sufficient .

5. Role in Hair Follicle Health:

• Angiogenesis is vital for hair follicle function, as it ensures the delivery of necessary nutrients and oxygen.
• By promoting angiogenesis, GHK-Cu supports hair follicle health, potentially reversing hair loss and encouraging hair regrowth .

Conclusion:

GHK-Cu peptide, through its angiogenic properties, plays a significant role in hair follicle health and hair regrowth. By stimulating blood vessel formation, it helps ensure that hair follicles receive adequate nourishment, which can aid in reversing hair loss and promoting new hair growth. The study highlights the potential therapeutic applications of GHK-Cu in treating hair loss conditions by leveraging its natural ability to enhance angiogenesis and tissue regeneration.

Article 8

Simeon, A., Wegrowski, Y., Bontemps, Y., & Maquart, F. X. (2000). Expression of Glycosaminoglycans and Small Proteoglycans in Wounds: Modulation by the Tripeptide-Copper Complex Glycyl-L-Histidyl-L-Lysine-Cu^2+. Journal of Investigative Dermatology, 115(6), 962-968.

This study investigates the role of the GHK-Cu peptide in hair loss and hair regrowth, emphasizing its impact on extracellular matrix components and wound healing processes, which are relevant to hair follicle health.

Key Points:

1. GHK-Cu Peptide Composition and Function:

• GHK-Cu (glycyl-L-histidyl-L-lysine-Cu^2+) is a tripeptide-copper complex known for its high affinity for copper ions and its role in stimulating wound healing and tissue repair​.
• The peptide promotes the synthesis of glycosaminoglycans (GAGs) and small proteoglycans (PGs), which are crucial for extracellular matrix formation.

2. Mechanism of Action:

• GHK-Cu enhances collagen production and GAG accumulation in wound tissues. This activity supports the structural integrity and function of hair follicles​.
• The peptide modulates the expression of decorin and biglycan, two small proteoglycans involved in collagen organization. Decorin expression is increased, while biglycan expression is decreased by GHK-Cu treatment, indicating a selective regulation of extracellular matrix components​.

3. Effects on Angiogenesis and Hair Follicle Health:

• GHK-Cu stimulates angiogenesis, the formation of new blood vessels, which is essential for providing nutrients and oxygen to hair follicles​.
• The increased decorin expression and collagen deposition enhance the formation of a mature extracellular matrix, potentially improving hair follicle strength and promoting hair regrowth​.

4. Proteolysis and Peptide Release:

• GHK-Cu is released from larger proteins like SPARC through proteolytic cleavage. This process generates bioactive peptides that can regulate various cellular activities, including angiogenesis and matrix remodeling, which are crucial for hair growth​.

5. Experimental Findings:

• In rat models, repeated GHK-Cu injections significantly increased collagen content and GAG accumulation in wound tissues, demonstrating the peptide's potent stimulatory effects on tissue repair and regeneration​.
• The study also showed that GHK-Cu selectively increased the synthesis of certain GAGs, such as chondroitin sulfate, further supporting its role in extracellular matrix modulation​.

Conclusion:

The GHK-Cu peptide plays a significant role in promoting hair regrowth and preventing hair loss through its effects on angiogenesis, collagen production, and extracellular matrix modulation. By enhancing the structural components and vascularization of hair follicles, GHK-Cu supports hair follicle health and function, offering potential therapeutic benefits for hair loss conditions.