woman brushing her hair exposing the gray hair and scalp
Instant Delivery, Peptides

Sermorelin Vs. GHK-Cu Vs. PT-141: Which Is The Best For Hair Loss Treatment?

01/23/2025 | by

Peptides like GHK-Cu, Sermorelin, and PT-141 are transforming hair loss treatments by addressing root causes such as inflammation, poor blood flow, and follicle miniaturization. GHK-Cu boosts collagen, improves scalp health, and stimulates dormant follicles. Sermorelin enhances growth hormone production, aiding cellular repair and follicle regeneration. PT-141’s potential is still emerging. These peptides offer promising, innovative solutions beyond traditional treatments like minoxidil or finasteride. Read further to find out which is the best hair loss treatment.

What is Hair Loss and How Can Peptides Help?

Hair loss is not a one-size-fits-all issue; it occurs in various forms, each with distinct causes and characteristics. The common denominator in most cases is a disruption in the hair follicle’s growth cycle—the natural phases that regulate the production and shedding of hair.

Peptides, short chains of amino acids, are becoming central to the conversation about hair rejuvenation due to their ability to interact with specific biological processes.

Types of Hair Loss

Androgenic Alopecia (Pattern Baldness):

The most prevalent form, affecting men and women, is often characterized by a receding hairline or thinning at the crown. It is largely influenced by genetics and hormonal factors, particularly the sensitivity of hair follicles to dihydrotestosterone (DHT) 1

man with bald spot on the top of the head

Alopecia Areata:

An autoimmune disorder where the body’s immune system mistakenly attacks hair follicles, leading to patchy hair loss. In severe cases, it can result in complete loss of scalp and body hair. 2

Telogen Effluvium:

A temporary form of hair loss often triggered by stress, illness, hormonal changes, or nutritional deficiencies. It involves an increased number of hair follicles entering the resting phase (telogen) prematurely, leading to excessive shedding. 3

Scarring Alopecias:

A less common group of conditions where inflammation damages the hair follicles irreversibly, leading to permanent hair loss. 4

These forms of hair loss highlight the multifactorial nature of the condition, underscoring the need for tailored treatments that address specific underlying causes.

The Promise of Peptides in Hair Restoration

Traditional hair loss treatments, such as topical minoxidil or oral finasteride, have been the mainstay for decades. While effective for some, these treatments come with limitations, including side effects, inconsistent results, and the need for long-term use. Enter peptides, a groundbreaking alternative that is changing the landscape of hair restoration.

Discover Complete Peptide Solutions

Enhance your health with our range of peptides, each crafted for specific benefits like boosting muscle, improving skin health, and reducing anxiety—all ready for easy at-home use.

GHK-Cu | PT-141 | Sermorelin | Ipamorelin | Selank | Thymosin Alpha 1

Explore the possibilities and order your tailored peptide therapy today!

What Are Peptides?

Peptides are short chains of amino acids, the building blocks of proteins. These molecules are naturally present in the body and play a critical role in various biological processes, including cell signaling, tissue repair, and hormonal regulation.

In the context of hair restoration, peptides are designed to mimic or enhance the body’s natural mechanisms to address the root causes of hair loss at a molecular level. 5 6

Stimulating Hair Follicle Activity:

Peptides can invigorate dormant hair follicles, encouraging them to re-enter the active growth phase (anagen) of the hair cycle. This action directly combats the thinning and miniaturization of follicles seen in androgenic alopecia.

Improving Blood Circulation:

Adequate blood flow to the scalp is essential for delivering nutrients and oxygen to hair follicles. Certain peptides promote vasodilation (widening of blood vessels), enhancing circulation and creating a more supportive environment for hair growth.

Reducing Inflammation:

In conditions like alopecia areata or scarring alopecias, inflammation plays a central role in follicle damage. Anti-inflammatory peptides help calm immune responses, protecting hair follicles from further harm.

Stimulating Collagen Production:

Collagen is a vital component of the scalp’s extracellular matrix, providing structural support to hair follicles. Peptides that boost collagen synthesis can help strengthen follicles and improve scalp health, indirectly fostering hair growth.

Promoting Cellular Repair:

By enhancing the body’s natural repair processes, peptides help regenerate damaged hair follicles, particularly in cases where oxidative stress or hormonal imbalances have disrupted normal functioning.

GHK-Cu Peptide: A Closer Look

GHK-Cu stands for glycyl-L-histidyl-L-lysine copper, a small but powerful peptide naturally present in our skin, blood, and bodily tissues. Its unique ability to bind with copper ions is what gives this peptide its name and its incredible therapeutic properties. Copper plays an essential role in various bodily functions, including collagen production, inflammation control, and tissue repair. By combining with copper ions, GHK-Cu supercharges these processes, making it a valuable tool for enhancing skin and hair health. 78

The body produces GHK-Cu naturally, but levels decline with age. This reduction can contribute to slower wound healing, increased inflammation, and decreased skin and follicular health, all of which can exacerbate hair loss. Supplementing with GHK-Cu peptide aims to restore these declining levels, targeting the root causes of hair thinning and loss.

woman brushing her hair exposing the gray hair and scalp

Mechanism of Action for Hair Growth

GHK-Cu’s hair regrowth potential lies in its ability to enhance the skin and follicle environment. It does so by:

Boosting Collagen and Elastin Production

Collagen and elastin are structural proteins essential for skin and follicle integrity. GHK-Cu stimulates the production of these proteins, creating a healthier scalp environment. A strong, well-supported scalp provides a better foundation for hair follicles to thrive, reducing the likelihood of thinning or breakage. 9

Enhancing Blood Flow to Hair Follicles

One of GHK-Cu’s standout abilities is promoting angiogenesis, the formation of new blood vessels. By increasing blood flow to the scalp, it ensures that hair follicles receive the nutrients and oxygen they need to grow. 10

Regulating Genes Linked to Hair Growth

GHK-Cu can influence gene expression in ways that support hair health. It activates genes involved in tissue regeneration and hair growth while suppressing those linked to follicle miniaturization—a hallmark of conditions like androgenic alopecia (pattern baldness). 10

Reducing Inflammation and Oxidative Stress

Inflammation and oxidative stress are common culprits in hair loss, especially in conditions like alopecia areata or aging-related hair thinning. GHK-Cu’s anti-inflammatory and antioxidant properties protect hair follicles from damage caused by free radicals and overactive immune responses. 10

Potential Benefits for Hair Loss

A healthy scalp is the foundation of strong hair. GHK-Cu repairs damaged scalp tissues, strengthens the skin barrier, and enhances hydration, all of which contribute to a better environment for hair growth. By improving the health of the scalp and supporting follicle regeneration, GHK-Cu can help “wake up” dormant follicles that have stopped producing hair, which is especially valuable for individuals with thinning hair.

Research and Evidence

Scientific studies and laboratory research back the efficacy of GHK-Cu in promoting hair growth and overall follicular health:

  • Improved Hair Density and Thickness:

    • Research shows that GHK-Cu can significantly enhance hair density and thickness. This is achieved through its effects on collagen production and dermal fibroblasts, the cells responsible for skin and follicle regeneration. 9

  • Support for Scalp Health:

    • GHK-Cu’s wound-healing properties also play a critical role in hair growth. By repairing damaged scalp tissue, the peptide creates the ideal conditions for hair follicles to function optimally. 11

  • Potential Synergy with Other Treatments:

    • Studies suggest that GHK-Cu can complement other hair loss treatments, such microneedling 12, by amplifying their effects and promoting faster recovery.

Understanding Sermorelin for Hair Growth

Sermorelin is a synthetic compound designed to mimic the body’s natural growth hormone-releasing hormone (GHRH). This peptide stimulates the pituitary gland, a small but powerful organ at the base of the brain, to produce and release human growth hormone (HGH). 

HGH is a vital hormone responsible for numerous functions, including cell repair, tissue regeneration, and overall metabolic balance. 13 Sermorelin does not supply HGH directly but acts as a catalyst, encouraging the body to produce its own, making it a more natural and controlled approach to boosting growth hormone levels.

Mechanism of Action for Hair Growth

Although Sermorelin was initially developed for purposes like addressing growth hormone deficiencies and promoting anti-aging benefits, its secondary effects make it a promising candidate for supporting hair growth. Its mechanisms are rooted in the way it enhances HGH levels and improves overall cellular activity.

Boosting Protein Synthesis

Hair follicles require a steady supply of proteins to maintain their structure and support growth. Sermorelin, as a synthetic form of GHRH, can stimulate the production of proteins, aiding in the repair and development of hair follicles that may have been damaged or weakened by stress, aging, or other factors. 14

Enhancing Blood Flow

Healthy hair follicles depend on an ample supply of oxygen and nutrients delivered through the bloodstream. By potentially improving systemic circulation, Sermorelin may ensure that the scalp receives the resources it needs for robust follicle activity. 15

Promoting Cellular Turnover

The natural life cycle of a hair follicle involves phases of growth, rest, and shedding. Sermorelin may be able to support cellular turnover, facilitating the replacement of damaged or aging cells with new, healthy ones. 16 This process may help restart the growth cycle in underperforming follicles.

Reducing Inflammation

Chronic scalp inflammation can hinder follicle health and lead to hair thinning or loss. The anti-inflammatory properties of Sermorelin, as a GHRH, can help create a more stable environment on the scalp, reducing stress on follicles and encouraging healthier growth. 17

Potential Benefits for Hair Loss

As we age, the natural production of HGH declines, which can negatively impact hair growth. Sermorelin counteracts this decline by boosting HGH levels, indirectly promoting stronger and more resilient follicles.

Hair follicles affected by stress, aging, or hormonal imbalances may experience disrupted growth cycles. Sermorelin’s effects on cellular regeneration and metabolism can help normalize these cycles, supporting steady and consistent hair growth.

Research and Evidence

While Sermorelin is not exclusively studied for hair loss, indirect evidence from HGH-related research suggests its potential. Increased HGH levels, as promoted by Sermorelin, have been linked to improved skin elasticity and wound healing. 18 These effects suggest that Sermorelin could indirectly support scalp health, a crucial factor for maintaining active and healthy hair follicles.

HGH’s role in promoting cell repair and tissue regeneration also suggests potential benefits for hair follicles, particularly those in need of repair or stimulation to re-enter the growth phase.

Understanding PT-141 for Hair Growth

While PT-141, also known as bremelanotide, has gained attention primarily as a treatment for sexual dysfunction, its potential effects on hair health are an intriguing avenue worth exploring.

PT-141 is a synthetic peptide initially developed to treat sexual arousal disorders in both men and women. Unlike traditional treatments that target blood flow directly, PT-141 operates on a deeper, neurological level. By stimulating melanocortin receptors in the brain, it promotes a cascade of effects that influence not only sexual function but also other areas like immune response, inflammation, and skin pigmentation. 19

The role of these melanocortin receptors extends beyond their more commonly known functions. They also regulate processes that may impact hair health, such as inflammation control, vascular health, and cellular repair.

Potential Benefits for Hair Loss

Although PT-141 has not been extensively studied in the context of hair loss, its biological effects suggest it may support scalp and follicle health in the following ways:

Reducing Inflammation

Chronic inflammation is a significant factor in many types of hair loss, including alopecia areata and scarring alopecias. PT-141’s activation of melanocortin receptors has been shown to reduce inflammation in various parts of the body. 20 By calming the immune response and lowering inflammatory markers, it could possibly create a more supportive environment for hair follicles to thrive.

Enhancing Pigmentation

Melanocortin receptors are also responsible for regulating melanin production, the pigment that gives hair its color. 21 By influencing these pathways, PT-141 could possibly enhance the pigmentation of existing hair, potentially improving its overall appearance. While this would not address the root causes of hair loss, it might offer a cosmetic benefit for those seeking to maintain their hair’s natural vibrancy.

Supporting Vascular Health

Healthy hair follicles depend on a steady supply of oxygen and nutrients delivered through a robust vascular system. PT-141’s effects on vascular pathways, particularly its role in promoting circulation 22, could indirectly aid follicle vitality. Better blood flow ensures that hair follicles receive the nutrients they need to remain active and productive.

Research and Evidence

At present, there is limited direct research linking PT-141 to hair loss or regrowth. Most studies focus on its efficacy in treating sexual dysfunction or its effects on inflammation and pigmentation. However, these secondary benefits provide a compelling rationale for future exploration into how PT-141 might be leveraged to support hair health.

GHK-Cu, Sermorelin, and PT-141: A Head-to-Head Comparison

To evaluate these peptides effectively, let’s compare their key attributes.

Peptide Mechanism of Action Potential Benefits Side Effects Cost Availability
GHK-Cu Boosts collagen, improves blood flow, reduces inflammation Promotes follicle repair and scalp health Minimal; rare skin irritation Moderate Widely available
Sermorelin Increases HGH, enhances circulation, aids cell turnover Stimulates follicle growth and metabolism Mild fatigue, headache Higher Prescription-only
PT-141 Activates melanocortin receptors Reduces inflammation, improves pigmentation Nausea, flushing Moderate to High Limited

Effectiveness

GHK-Cu is the most directly researched peptide for hair loss, offering proven benefits like follicle repair, reduced inflammation, and improved scalp circulation. Sermorelin, while not hair-specific, supports systemic health by boosting natural growth hormone levels, which can indirectly aid hair regrowth in cases linked to hormonal or metabolic imbalances. PT-141 may hold promise as part of a broader treatment plan. Each peptide targets different mechanisms, making their effectiveness context-dependent.

Safety

All three peptides have favorable safety profiles, but individual tolerance varies. GHK-Cu is the safest and most widely tolerated, especially in topical applications. Sermorelin is generally safe but requires monitoring due to its systemic effects. PT-141 is known for potential side effects like nausea and flushing, which may deter some users. Overall, these peptides are low-risk when used appropriately, however professional guidance is recommended to ensure safe and effective use.

Cost and Accessibility

GHK-Cu is more affordable and easily available in topical forms, making it the most accessible of the three peptides. Sermorelin, while effective, requires a prescription, limiting its availability and convenience for some users. PT-141 is primarily marketed for non-hair-related conditions, which restricts its accessibility as a hair loss treatment. Cost and ease of acquisition vary, with GHK-Cu being the most user-friendly option.

Combination Therapy

Combining these peptides could yield synergistic benefits by addressing hair loss from multiple angles. GHK-Cu directly targets follicle health, Sermorelin provides systemic hormonal support, and PT-141 may enhance circulation and reduce inflammation. However, combining peptides requires careful dosing and medical supervision to avoid adverse effects. When used together under professional guidance, these peptides may complement each other for more comprehensive hair restoration results.

Conclusion

When it comes to finding the best peptide for hair loss, GHK-Cu stands out for its targeted action and robust research backing. However, Sermorelin and PT-141 have unique advantages that may suit specific cases or be incorporated into combination therapies. Ultimately, the choice depends on individual needs, medical history, and consultation with a healthcare professional.

Peptides represent the cutting edge of hair restoration science, holding the promise of revitalized follicles and renewed confidence for those grappling with hair loss. By staying informed and seeking expert guidance, you can harness these advancements to unlock the full potential of your hair health.

Transform Your Health with Our Peptide Therapy

Enhance your health with our comprehensive range of peptides, each designed for specific benefits. From combating aging to boosting muscle development and recovery, educing anxiety, and more, peptide treatments may help you achieve a wide range of health goals. Our peptide treatments are delivered to your doorstep and self-administered in the comfort of your home.

GHK-Cu | PT-141 | Sermorelin | Ipamorelin | Selank | Thymosin Alpha 1

Explore the possibilities and order your tailored peptide therapy today!

Order your peptides today by clicking the button below!

  • Fosgerau K, Hoffmann T. Peptide therapeutics: current status and future directions. Drug Discov Today. 2015;20(1):122-128. doi:10.1016/j.drudis.2014.10.003
  • Du, Zhenjiao & Li, Yonghui. (2022). Review and perspective on bioactive peptides: A roadmap for research, development, and future opportunities. Journal of Agriculture and Food Research. 9. 100353. 10.1016/j.jafr.2022.100353.
  • Matsui, T., Yoshino, A. & Tanaka, M. A trip of peptides to the brain. Food Prod Process and Nutr 2, 30 (2020). https://doi.org/10.1186/s43014-020-00044-8
  • Katayama, S. and Nakamura, S. (2019), Emerging roles of bioactive peptides on brain health promotion. Int J Food Sci Technol, 54: 1949-1955. https://doi.org/10.1111/ijfs.14076
  • Asua D, Bougamra G, Calleja-Felipe M, Morales M, Knafo S. Peptides Acting as Cognitive Enhancers. Neuroscience. 2018;370:81-87. doi:10.1016/j.neuroscience.2017.10.002
  • La Manna S, Di Natale C, Florio D, Marasco D. Peptides as Therapeutic Agents for Inflammatory-Related Diseases. Int J Mol Sci. 2018;19(9):2714. Published 2018 Sep 11. doi:10.3390/ijms19092714
  • Bernabeu-Zornoza A, Coronel R, Palmer C, Martín A, López-Alonso V, Liste I. Neurogenesis Is Increased in Human Neural Stem Cells by Aβ40 Peptide. Int J Mol Sci. 2022;23(10):5820. Published 2022 May 22. doi:10.3390/ijms23105820
  • Yeo XY, Cunliffe G, Ho RC, Lee SS, Jung S. Potentials of Neuropeptides as Therapeutic Agents for Neurological Diseases. Biomedicines. 2022;10(2):343. Published 2022 Feb 1. doi:10.3390/biomedicines10020343
  • Autry AE, Monteggia LM. Brain-derived neurotrophic factor and neuropsychiatric disorders. Pharmacol Rev. 2012;64(2):238-258. doi:10.1124/pr.111.005108 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3310485/
  • Gusev EI, Martynov MY, Kostenko EV, Petrova LV, Bobyreva SN. Éffektivnost’ semaksa pri lechenii bol’nykh na raznykh stadiiakh ishemicheskogo insul’ta [The efficacy of semax in the tretament of patients at different stages of ischemic stroke]. Zh Nevrol Psikhiatr Im S S Korsakova. 2018;118(3. Vyp. 2):61-68. doi:10.17116/jnevro20181183261-68
  • Tsai SJ. Semax, an analogue of adrenocorticotropin (4-10), is a potential agent for the treatment of attention-deficit hyperactivity disorder and Rett syndrome. Med Hypotheses. 2007;68(5):1144-1146. doi:10.1016/j.mehy.2006.07.017
  • Kaplan, A.Y.A., Kochetova, A.G., Nezavibathko, V.N., Rjasina, T.V. and Ashmarin, I.P. (1996), Synthetic acth analogue semax displays nootropic-like activity in humans. Neurosci. Res. Comm., 19: 115-123. https://doi.org/10.1002/(SICI)1520-6769(199609)19:2<115::AID-NRC171>3.0.CO;2-B
  • Sun X, Deng Y, Fu X, Wang S, Duan R, Zhang Y. AngIV-Analog Dihexa Rescues Cognitive Impairment and Recovers Memory in the APP/PS1 Mouse via the PI3K/AKT Signaling Pathway. Brain Sci. 2021;11(11):1487. Published 2021 Nov 11. doi:10.3390/brainsci11111487
  • Ho JK, Nation DA. Cognitive benefits of angiotensin IV and angiotensin-(1-7): A systematic review of experimental studies. Neurosci Biobehav Rev. 2018;92:209-225. doi:10.1016/j.neubiorev.2018.05.005
  • McReynolds MR, Chellappa K, Baur JA. Age-related NAD+ decline. Exp Gerontol. Published online February 22, 2020. doi:10.1016/j.exger.2020.110888
  • Braidy N, Liu Y. NAD+ therapy in age-related degenerative disorders: A benefit/risk analysis. Exp Gerontol. 2020;132:110831. doi:10.1016/j.exger.2020.110831
  • Kasian A, Kolomin T, Andreeva L, et al. Peptide Selank Enhances the Effect of Diazepam in Reducing Anxiety in Unpredictable Chronic Mild Stress Conditions in Rats. Behav Neurol. 2017;2017:5091027. doi:10.1155/2017/5091027
  • Filatova E, Kasian A, Kolomin T, et al. GABA, Selank, and Olanzapine Affect the Expression of Genes Involved in GABAergic Neurotransmission in IMR-32 Cells. Front Pharmacol. 2017;8:89. Published 2017 Feb 28. doi:10.3389/fphar.2017.00089
  • Kolik LG, Nadorova AV, Kozlovskaya MM. Efficacy of peptide anxiolytic selank during modeling of withdrawal syndrome in rats with stable alcoholic motivation. Bull Exp Biol Med. 2014;157(1):52-55. doi:10.1007/s10517-014-2490-4
  • Khavinson V, Linkova N, Kozhevnikova E, Trofimova S. EDR Peptide: Possible Mechanism of Gene Expression and Protein Synthesis Regulation Involved in the Pathogenesis of Alzheimer’s Disease. Molecules. 2020;26(1):159. Published 2020 Dec 31. doi:10.3390/molecules26010159
  • Katayama, S. and Nakamura, S. (2019), Emerging roles of bioactive peptides on brain health promotion. Int J Food Sci Technol, 54: 1949-1955. https://doi.org/10.1111/ijfs.14076
  • Pao PC, Seo J, Lee A, et al. A Cdk5-derived peptide inhibits Cdk5/p25 activity and improves neurodegenerative phenotypes. Proc Natl Acad Sci U S A. 2023;120(16):e2217864120. doi:10.1073/pnas.2217864120
  • Sun X, Deng Y, Fu X, Wang S, Duan R, Zhang Y. AngIV-Analog Dihexa Rescues Cognitive Impairment and Recovers Memory in the APP/PS1 Mouse via the PI3K/AKT Signaling Pathway. Brain Sci. 2021;11(11):1487. Published 2021 Nov 11. doi:10.3390/brainsci11111487
  • Cheng L, Shi C, Li X, Matsui T. Impact of Peptide Transport and Memory Function in the Brain. Nutrients. 2024; 16(17):2947. https://doi.org/10.3390/nu16172947
  • Knafo S, Venero C, Sánchez-Puelles C, et al. Facilitation of AMPA receptor synaptic delivery as a molecular mechanism for cognitive enhancement. PLoS Biol. 2012;10(2):e1001262. doi:10.1371/journal.pbio.1001262
  • Zozulia AA, Neznamov GG, Siuniakov TS, et al. Zh Nevrol Psikhiatr Im S S Korsakova. 2008;108(4):38-48.
  • Wang J, Sun R, Xia L, Zhu X, Zhang Q, Ye Y. Potential Therapeutic Effects of NAMPT-Mediated NAD Biosynthesis in Depression In Vivo. Brain Sci. 2022;12(12):1699. Published 2022 Dec 11. doi:10.3390/brainsci12121699
  • Ilina A, Khavinson V, Linkova N, Petukhov M. Neuroepigenetic Mechanisms of Action of Ultrashort Peptides in Alzheimer’s Disease. Int J Mol Sci. 2022;23(8):4259. Published 2022 Apr 12. doi:10.3390/ijms23084259
  • Dergunova LV, Filippenkov IB, Limborska SA, Myasoedov NF. Neuroprotective Peptides and New Strategies for Ischemic Stroke Drug Discoveries. Genes. 2023; 14(5):953. https://doi.org/10.3390/genes14050953
  • Khavinson VK, Popovich IG, Linkova NS, Mironova ES, Ilina AR. Peptide Regulation of Gene Expression: A Systematic Review. Molecules. 2021;26(22):7053. Published 2021 Nov 22. doi:10.3390/molecules26227053
  • Burgdorf JS, Yoon S, Dos Santos M, Lammert CR, Moskal JR, Penzes P. An IGFBP2-derived peptide promotes neuroplasticity and rescues deficits in a mouse model of Phelan-McDermid syndrome. Mol Psychiatry. 2023;28(3):1101-1111. doi:10.1038/s41380-022-01904-0
  • Karisetty BC, Bhatnagar A, Armour EM, Beaver M, Zhang H, Elefant F. Amyloid-β Peptide Impact on Synaptic Function and Neuroepigenetic Gene Control Reveal New Therapeutic Strategies for Alzheimer’s Disease. Front Mol Neurosci. 2020;13:577622. Published 2020 Nov 13. doi:10.3389/fnmol.2020.577622

References

[1] Lolli, Francesca, Francesco Pallotti, Alfredo Rossi, Maria C. Fortuna, Gemma Caro, Andrea Lenzi, Andrea Sansone, and Francesco Lombardo. 2017. “Androgenetic alopecia: a review.” Endocrine 57 (1): 9–17.;

[2] Juárez-Rendón, Karina J, Gildardo Rivera Sánchez, Miguel Á Reyes-López, José E García-Ortiz, Virgilio Bocanegra-García, Iliana Guardiola-Avila, and María L Altamirano-García. 2017. “Alopecia Areata. Current situation and perspectives.” Archivos Argentinos De Pediatria 115 (6).;

[3] Asghar, Fahham, Nazia Shamim, Umar Farooque, Haris Sheikh, and Ramsha Aqeel. 2020. “Telogen Effluvium: A Review of the Literature.” Cureus, May. ;

[4] Larrondo, Jorge, and Amy J. McMichael. 2023. “Scarring Alopecia.” Dermatologic Clinics 41 (3): 519–37.;

[5] Lee, Jung Ok, Yujin Kim, Jung Min Lee, Jang Mi Suk, Inhee Jung, Sun Young Choi, Kwang Ho Yoo, Joon Seok, and Beom Joon Kim. 2024. “AP collagen peptides (APCPs) promote hair growth by activating the GSK‐3β/β‐catenin pathway and improve hair condition.” Experimental Dermatology 33 (7).;

[6] Hwang, Su Bin, Hyeon Ju Park, and Bog-Hieu Lee. 2022. “Hair-Growth-Promoting Effects of the Fish Collagen Peptide in Human Dermal Papilla Cells and C57BL/6 Mice Modulating Wnt/β-Catenin and BMP Signaling Pathways.” International Journal of Molecular Sciences 23 (19): 11904.;

[7] Lee, Weon Ju, Hyun Bo Sim, Yong Hyun Jang, Seok-Jong Lee, Do Won Kim, and Soon-Ho Yim. 2016. “Efficacy of a Complex of 5-Aminolevulinic Acid and Glycyl-Histidyl-Lysine Peptide on Hair Growth.” Annals of Dermatology 28 (4): 438.;

[8] Pickart, Loren, Jessica Michelle Vasquez-Soltero, and Anna Margolina. 2015. “GHK Peptide as a Natural Modulator of Multiple Cellular Pathways in Skin Regeneration.” BioMed Research International 2015 (January): 1–7. ;

[9] Pickart, Loren, and Anna Margolina. 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.;

[10] Pickart, Loren, Jessica Vasquez-Soltero, and Anna Margolina. 2015a. “GHK-Cu may Prevent Oxidative Stress in Skin by Regulating Copper and Modifying Expression of Numerous Antioxidant Genes.” Cosmetics 2 (3): 236–47. ;

[10] Pickart, Loren, Jessica Vasquez-Soltero, and Anna Margolina. 2015a. “GHK-Cu may Prevent Oxidative Stress in Skin by Regulating Copper and Modifying Expression of Numerous Antioxidant Genes.” Cosmetics 2 (3): 236–47. ;

[10] Pickart, Loren, Jessica Vasquez-Soltero, and Anna Margolina. 2015a. “GHK-Cu may Prevent Oxidative Stress in Skin by Regulating Copper and Modifying Expression of Numerous Antioxidant Genes.” Cosmetics 2 (3): 236–47. ;

[9] Pickart, Loren, and Anna Margolina. 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.;

[11] Liu, Tianqi, Ying Liu, Xiaoyu Zhao, Liguo Zhang, Wei Wang, De Bai, Ya Liao, Zhenyuan Wang, Mi Wang, and Jiaheng Zhang. 2023. “Thermodynamically stable ionic liquid microemulsions pioneer pathways for topical delivery and peptide application.” Bioactive Materials 32 (November): 502–13.;

[12] Li, Hairui, Yong Sheng Jason Low, Hui Ping Chong, Melvin T. Zin, Chi-Ying Lee, Bo Li, Melvina Leolukman, and Lifeng Kang. 2015. “Microneedle-Mediated Delivery of Copper Peptide Through Skin.” Pharmaceutical Research, February. ;

[13] Sinha, Deepankar K., Adithya Balasubramanian, Alexander J. Tatem, Jorge Rivera-Mirabal, Justin Yu, Jason Kovac, Alexander W. Pastuszak, and Larry I. Lipshultz. 2020. “Beyond the androgen receptor: the role of growth hormone secretagogues in the modern management of body composition in hypogonadal males.” Translational Andrology and Urology 9 (S2): S149–59.;

[14] Møller, Niels, Kenneth C. Copeland, and K. Sreekumaran Nair. 2007. “Growth Hormone Effects on Protein Metabolism.” Endocrinology and Metabolism Clinics of North America 36 (1): 89–100.;

[15] Caicedo, Diego, Oscar Díaz, Pablo Devesa, and Jesús Devesa. 2018. “Growth Hormone (GH) and Cardiovascular System.” International Journal of Molecular Sciences 19 (1): 290.;

[16] Elkhenany, Hoda, Abdelrahman AlOkda, Ahmed El-Badawy, and Nagwa El-Badri. 2018. “Tissue regeneration: Impact of sleep on stem cell regenerative capacity.” Life Sciences 214 (October): 51–61.;

[17] Palacios, Blanca Soler, Concha Nieto, Pilar Fajardo, Arturo González De La Aleja, Nuria Andrés, Ángeles Dominguez-Soto, Pilar Lucas, et al. 2020. “Growth Hormone Reprograms Macrophages toward an Anti-Inflammatory and Reparative Profile in an MAFB-Dependent Manner.” The Journal of Immunology 205 (3): 776–88. ;

[18] Caicedo, Diego, and Jesús Devesa. 2019. “Growth Hormone (GH) and Wound Healing.” In IntechOpen eBooks.;

[19] Mayer, Danielle, and Sarah E. Lynch. 2020. “Bremelanotide: New Drug Approved for Treating Hypoactive Sexual Desire Disorder.” Annals of Pharmacotherapy 54 (7): 684–90.;

[20] Wang, Wei, Dong-Yu Guo, Yue-Jun Lin, and Ya-Xiong Tao. 2019. “Melanocortin Regulation of Inflammation.” Frontiers in Endocrinology 10 (October). ;

[21] Horrell, Erin M. Wolf, Mary C. Boulanger, and John A. D’Orazio. 2016. “Melanocortin 1 Receptor: Structure, Function, and Regulation.” Frontiers in Genetics 7 (May). ;

[22] Humphreys, Michael H., Xi-Ping Ni, and David Pearce. 2011. “Cardiovascular effects of melanocortins.” European Journal of Pharmacology 660 (1): 43–52.;