# References

> References — Research Peptide Fundamentals — Altera Peptides — Research Peptide Fundamentals research peptides: the complete signed bibliography supporting the Altera Peptides evidence map.

**SOURCE REGISTER / 22 ENTRIES**

The bibliography behind every numbered claim, preserved as composed.

## How this register works

This register contains the complete signed source set for the four compound files. NAD+ uses references 1–7, GHK-Cu uses 8–12, retatrutide uses 13–17, and KPV uses 18–22. Numbered citations on the site point into this list. Source type still matters: a review, structural experiment, ex vivo skin study, animal model, and randomized human trial answer different questions. The citation proves traceability; study design determines how far the conclusion can travel.

## References

[1] Vinten KT, Trętowicz MM, Coskun E, van Weeghel M, Cantó C, Zapata-Pérez R, Janssens GE, Houtkooper RH. NAD(+) precursor supplementation in human ageing: clinical evidence and challenges. Nat Metab. 2025;7:1974-1990. https://pubmed.ncbi.nlm.nih.gov/41083806/
[2] Yi L, Maier AB, Tao R, Lin Z, Vaidya A, Pendse S, Thasma S, Andhalkar N, Avhad G, Kumbhar V. The efficacy and safety of β-nicotinamide mononucleotide (NMN) supplementation in healthy middle-aged adults: a randomized, multicenter, double-blind, placebo-controlled, parallel-group, dose-dependent clinical trial. GeroScience 2023. 2023;45:29-43. https://pubmed.ncbi.nlm.nih.gov/36482258/
[3] Yoshino M, Yoshino J, Kayser BD, Patti GJ, Franczyk MP, Mills KF, Sindelar M, Pietka T, Patterson BW, Imai SI, Klein S. Nicotinamide mononucleotide increases muscle insulin sensitivity in prediabetic women. Science. 2021;372:1224-1229. https://pubmed.ncbi.nlm.nih.gov/33888596/
[4] Covarrubias AJ, et al. NAD+ metabolism and its roles in cellular processes during ageing. Nat Rev Mol Cell Biol. 2021. https://pubmed.ncbi.nlm.nih.gov/33353981/
[5] Conze D, Brenner C, Kruger CL. Safety and Metabolism of Long-term Administration of NIAGEN (Nicotinamide Riboside Chloride) in a Randomized, Double-Blind, Placebo-controlled Clinical Trial of Healthy Overweight Adults. Sci Rep. 2019;9:9772. https://pubmed.ncbi.nlm.nih.gov/31278280/
[6] Camacho-Pereira J, Tarragó MG, Chini CCS, Nin V, Escande C, Warner GM, Puranik AS, Schoon RA, Reid JM, Galina A, Chini EN. CD38 Dictates Age-Related NAD Decline and Mitochondrial Dysfunction through an SIRT3-Dependent Mechanism. Cell Metab. 2016;23:1127-1139. https://pubmed.ncbi.nlm.nih.gov/27304511/
[7] Koay YC, McIntosh B, Ng YH, et al. The Heart Has Intrinsic Ketogenic Capacity that Mediates NAD(+) Therapy in HFpEF. Circulation Research. 2025;136:1113-1130. https://pubmed.ncbi.nlm.nih.gov/40211954/
[8] Mortazavi SM, Mohammadi Vadoud SA, Moghimi HR. Topically applied GHK as an anti-wrinkle peptide: Advantages, problems and prospective. BioImpacts. 2025;15:30071. https://pmc.ncbi.nlm.nih.gov/articles/PMC11830136/
[9] Pickart L, Margolina A. Regenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data. International Journal of Molecular Sciences. 2018;19(7):1987. https://pmc.ncbi.nlm.nih.gov/articles/PMC6073405/
[10] Lee WJ, Sim HB, Jang YH, Lee SJ, Kim DW, Yim SH. Efficacy of a Complex of 5-Aminolevulinic Acid and Glycyl-Histidyl-Lysine Peptide on Hair Growth. Annals of Dermatology. 2016;28(4):438-443. https://pmc.ncbi.nlm.nih.gov/articles/PMC4969472/
[11] Pickart L, Vasquez-Soltero JM, Margolina A. GHK Peptide as a Natural Modulator of Multiple Cellular Pathways in Skin Regeneration. BioMed Research International. 2015;2015:648108. https://pmc.ncbi.nlm.nih.gov/articles/PMC4508379/
[12] Hostynek JJ, Dreher F, Maibach HI. Human skin penetration of a copper tripeptide in vitro as a function of skin layer. Inflammation Research. 2011;60(1):79-86. https://pmc.ncbi.nlm.nih.gov/articles/PMC3016279/
[13] Katsi V, Koutsopoulos G, Fragoulis C, Dimitriadis K, Tsioufis K. Retatrutide-A Game Changer in Obesity Pharmacotherapy. Biomolecules. 2025;15:796. https://pmc.ncbi.nlm.nih.gov/articles/PMC12190491/
[14] Li W, Zhou Q, Cong Z, Yuan Q, Li W, Zhao F, Xu HE, Zhao LH, Yang D, Wang MW. Structural insights into the triple agonism at GLP-1R, GIPR and GCGR manifested by retatrutide. Cell Discovery. 2024;10:77. https://pmc.ncbi.nlm.nih.gov/articles/PMC11255275/
[15] Sanyal AJ, Kaplan LM, Frias JP, Brouwers B, Wu Q, Thomas MK, Harris C, Schloot NC, Du Y, Mather KJ, Haupt A, Hartman ML. Triple hormone receptor agonist retatrutide for metabolic dysfunction-associated steatotic liver disease: a randomized phase 2a trial. Nature Medicine. 2024;30:2037-2048. https://pmc.ncbi.nlm.nih.gov/articles/PMC11271400/
[16] Jastreboff AM, et al. Triple-Hormone-Receptor Agonist Retatrutide for Obesity - A Phase 2 Trial. N Engl J Med. 2023;389(6):514-526. https://pubmed.ncbi.nlm.nih.gov/37366315/
[17] Rosenstock J, et al. Retatrutide, a GIP, GLP-1 and glucagon receptor agonist, for people with type 2 diabetes: a randomised, double-blind, placebo and active-controlled, parallel-group, phase 2 trial. Lancet. 2023;402(10401):529-544. https://pubmed.ncbi.nlm.nih.gov/37385280/
[18] Zhang D, et al. PepT1-targeted nanodrug based on co-assembly of anti-inflammatory peptide and immunosuppressant for combination treatment of acute and chronic DSS-induced colitis. Front Pharmacol. 2024;15:1442876. https://pubmed.ncbi.nlm.nih.gov/39211778/
[19] Xiao B, Xu Z, Viennois E, et al. Orally Targeted Delivery of Tripeptide KPV via Hyaluronic Acid-Functionalized Nanoparticles Efficiently Alleviates Ulcerative Colitis. Mol Ther. 2017;25(7):1628-1640. https://pubmed.ncbi.nlm.nih.gov/28143741/
[20] Dalmasso G, Charrier-Hisamuddin L, Nguyen HT, Yan Y, Sitaraman S, Merlin D. PepT1-mediated tripeptide KPV uptake reduces intestinal inflammation. Gastroenterology. 2008;134(1):166-178. https://pubmed.ncbi.nlm.nih.gov/18061177/
[21] Kannengiesser K, Maaser C, Heidemann J, et al. Melanocortin-derived tripeptide KPV has anti-inflammatory potential in murine models of inflammatory bowel disease. Inflamm Bowel Dis. 2008;14(3):324-331. https://pubmed.ncbi.nlm.nih.gov/18092346/
[22] Brzoska T, Luger TA, Maaser C, Abels C, Bohm M. Alpha-melanocyte-stimulating hormone and related tripeptides: biochemistry, antiinflammatory and protective effects in vitro and in vivo, and future perspectives for the treatment of immune-mediated inflammatory diseases. Endocr Rev. 2008;29(5):581-602. https://pubmed.ncbi.nlm.nih.gov/18612139/

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