RPEP-00017 · 1983Mice lost immune killing power as they aged. By 24 months (equivalent to roughly 70+ human years), their spleen cells were much weaker at destroying tumor cells compared to 1-month-old mice.
Four thymic hormones were tested: FTS (serum thymic factor), TP5 (a fragment of thymopoietin), TM4 (a synthetic version of TP5), and thymosin fraction V. Each worked differently depending on the age of the mouse and the dose used.
The most striking result: TM4 at a very low dose (1 nanogram) actually suppressed immune killing in young mice but significantly boosted it in 12- and 24-month-old mice. FTS and TP5 partially restored killing ability in old mice. Thymosin fraction V had modest and inconsistent effects.
Ghanta, V K; Noble, P J; Brown, M E; Cox, P J; Hiramoto, N S; Hiramoto, R N · Animal Study
RPEP-00235 · 1992Thymic hormones (thymosin alpha-1, thymulin, thymopoietin) decline with age alongside thymic involution, and their supplementation shows potential for partially restoring age-related immune deficits.
Hadden, J W; Malec, P H; Coto, J; Hadden, E M · Review
RPEP-00357 · 1996Daily oral MK-677 significantly stimulated the GH-IGF-1 axis in healthy elderly adults aged 64-81, raising levels toward those seen in younger individuals.
Chapman, I M; Bach, M A; Van Cauter, E; Farmer, M; Krupa, D; Taylor, A M; Schilling, L M; Cole, K Y; Skiles, E H; Pezzoli, S S; Hartman, M L; Veldhuis, J D; Gormley, G J; Thorner, M O · RCT
RPEP-00434 · 1997GHRH and GHRPs can restore GH secretion in aging and disease, addressing the visceral fat accumulation and metabolic changes associated with GH decline.
Thorner, M O; Chapman, I M; Gaylinn, B D; Pezzoli, S S; Hartman, M L · Review
RPEP-00461 · 1998GH secretagogues function as somatostatin antagonists at the hypothalamic-pituitary level and can restore youthful GH secretion patterns in elderly subjects.
Fuh, V L; Bach, M A · Review
RPEP-00524 · 1999The thymic-pituitary axis forms a bidirectional neuroendocrine circuit that deteriorates with age, contributing to immunosenescence. Thymic peptide supplementation may restore immune-endocrine homeostasis in aging.
Goya, R G; Bolognani, F · Review
RPEP-00525 · 1999Aging causes progressive disruption of the pituitary-thymic bidirectional circuit: reduced thymic peptide production, altered pituitary hormone output, and impaired integration between immune and endocrine systems, creating a self-reinforcing decline.
Goya, R G; Brown, O A; Bolognani, F · Review
RPEP-00833 · 2003Epithalon peptide (Ala-Glu-Asp-Gly) induced telomerase catalytic subunit (hTERT) expression, telomerase enzymatic activity, and telomere elongation in telomerase-negative human fetal fibroblasts.
Khavinson, V Kh; Bondarev, I E; Butyugov, A A · In Vitro
RPEP-00834 · 2003In a 6-8 year follow-up study of 266 elderly people, treatment with thymic peptide (Thymalin) and pineal peptide (Epithalamin) bioregulators for 2-3 years was associated with dramatic reductions in mortality: 2.0-2.1 times lower with Thymalin, 1.6-1.8 times lower with Epithalamin, and 2.5 times lower with the combination. The most striking result: patients treated with both peptides annually for 6 years showed a 4.1-fold decrease in mortality compared to controls.
Treated patients also showed improved cardiovascular, endocrine, immune, and nervous system function, a 2.0-2.4 fold reduction in respiratory infections, and lower rates of ischemic heart disease, hypertension, osteoarthritis, and osteoporosis.
Khavinson, Vladimir Kh; Morozov, Vyacheslav G · Clinical Trial
RPEP-00887 · 2004Combined SC GHRP-2 + GHRH infusion sustainably elevated pulsatile GH, IGF-1, and IGFBP-3 in healthy older adults without desensitization, with synergy exceeding individual effects and women showing greater response than men.
Bowers, Cyril Y; Granda, Ramona; Mohan, Subburaman; Kuipers, Jonathan; Baylink, David; Veldhuis, Johannes D · Clinical Trial
RPEP-00933 · 2004Epithalon peptide treatment enabled human somatic cells to overcome the Hayflick division limit (normally ~50 divisions), extending replicative lifespan through telomerase activation and telomere maintenance.
Khavinson, V Kh; Bondarev, I E; Butyugov, A A; Smirnova, T D · In Vitro
RPEP-01029 · 2005Ghrelin demonstrates comprehensive immunomodulatory activity: anti-inflammatory cytokine suppression, thymic output enhancement, immune cell function promotion, and potential reversal of age-related immune decline (immunosenescence).
Dixit, Vishwa Deep; Taub, Dennis D · Review
RPEP-01108 · 2005SS-31, a cell-permeable peptide targeting the inner mitochondrial membrane, prevented mitochondrial depolarization and apoptosis in neuronal cells exposed to oxidative stress — demonstrating precision subcellular peptide targeting for protecting the cell's energy source.
Zhao, Kesheng; Luo, Guoxiong; Giannelli, Serena; Szeto, Hazel H · In Vitro
RPEP-01224 · 2007Thymosin alpha-1 as an influenza vaccine adjuvant improved seroconversion and antibody titers in elderly adults with normally impaired vaccine responses, addressing the immunosenescence that makes influenza vaccination less effective in the aged.
Ershler, William B; Gravenstein, Stefan; Geloo, Zeba S · Review
RPEP-01227 · 2007GH secretagogues reversed age-related GH/IGF-I axis decline in aged rats by restoring hypothalamic GHRH sensitivity and pituitary responsiveness, with combined GHRP + GHRH achieving the most complete axis restoration for anti-aging neuroendocrine therapy.
Frutos, Miriam García-San; Cacicedo, Lucinda; Fernández, Carolina; Vicent, David; Velasco, Beatriz; Zapatero, Helena; Sánchez-Franco, Franco · Animal Study
RPEP-01290 · 2007Ghrelin receptor agonists demonstrate multi-system anti-aging potential: restoring GH/IGF-1 axis, improving body composition (lean mass/fat ratio), enhancing cardiac function, boosting immune competence, and supporting cognitive function in aging models — comprehensive geroscience intervention.
Smith, Roy G; Sun, Yuxiang; Jiang, Hong; Albarran-Zeckler, Rosie; Timchenko, Nikolai · Review
RPEP-01301 · 2007Controlled E2 repletion demonstrated tripartite estrogen regulation of GH secretion: enhanced GH secretagogue (GHRP) pathway sensitivity, reduced somatostatin inhibition, and modified GH autonegative feedback — three independent estrogen-GH control mechanisms confirmed.
Veldhuis, Johannes D; Cosma, Mihaela; Erickson, Dana; Paulo, Remberto; Mielke, Kristi; Farhy, Leon S; Bowers, Cyril Y · Clinical Trial
RPEP-01349 · 2008GH/IGF-1 axis decline correlates with Alzheimer's disease progression, with IGF-1 supporting neuronal survival, beta-amyloid clearance, and synaptic function — GH secretagogues that restore this axis may offer neuroprotective therapeutic benefit for dementia.
Gómez, José Manuel · Review
RPEP-01392 · 2008One year of oral MK-677 in healthy older adults (n=65) increased fat-free mass (+1.1 kg), GH, and IGF-1 but also increased fat mass, fasting glucose, and insulin resistance — the most comprehensive long-term RCT showing MK-677's mixed metabolic profile in aging.
Nass, Ralf; Pezzoli, Suzan S; Oliveri, Mary Clancy; Patrie, James T; Harrell, Frank E; Clasey, Jody L; Heymsfield, Steven B; Bach, Mark A; Vance, Mary Lee; Thorner, Michael O · RCT
RPEP-01402 · 2008GHK-Cu comprehensively reviewed: stimulates collagen/glycosaminoglycan synthesis, wound healing, hair growth, and reprograms gene expression (1,584 genes) toward tissue repair and anti-aging — the most versatile copper-binding tripeptide in regenerative medicine.
Pickart, Loren · Review
RPEP-04997 · 2020Mitochondrial-derived peptides serve as retrograde metabolic signals — declining in metabolic disease but rising during adaptive stress responses like exercise — and can improve insulin sensitivity when administered therapeutically.
Merry, Troy L; Chan, Alex; Woodhead, Jonathan S T; Reynolds, Joseph C; Kumagai, Hiroshi; Kim, Su-Jeong; Lee, Changhan · Review
RPEP-05003 · 2020SS-31 partitions into the mitochondrial membrane interface and modulates surface electrostatics in a charge-dependent manner, with demonstrated reduction of calcium stress as a proof-of-concept protective mechanism.
Mitchell, Wayne; Ng, Emily A; Tamucci, Jeffrey D; Boyd, Kevin J; Sathappa, Murugappan; Coscia, Adrian; Pan, Meixia; Han, Xianlin; Eddy, Nicholas A; May, Eric R; Szeto, Hazel H; Alder, Nathan N · In Vitro
RPEP-05082 · 2020ERJ-CP at 3 mg/mL extended natural aging Drosophila lifespan by 11.16%, upregulated antioxidant enzymes (T-SOD, GSH-Px, CAT), and reduced oxidative damage markers (MDA, PCO) while improving physical performance.
Qiu, Wenjing; Chen, Xu; Tian, Yongqi; Wu, Daping; Du, Ming; Wang, Shaoyun · Animal Study
RPEP-05092 · 2020TSCP at 1 mg/mL reduced AAPH-induced hemolysis from 56.35% to 18.78% (p<0.01). At 2.5 mg/10g/day oral dosing, TSCP prolonged exhaustive swimming time while decreasing serum lactic acid, urea nitrogen, and creatine kinase, and increasing glycogen and SOD.
Ren, Yao; Wu, Hui; Chi, Yuanlong; Deng, Ruijie; He, Qiang · Animal Study
RPEP-05345 · 2021A 16-week aerobic and resistance exercise intervention significantly increased MOTS-c levels in non-Hispanic White breast cancer survivors, with post-exercise MOTS-c associated with reductions in fat mass, body weight, HOMA-IR, and CRP, and increased lean mass (p < 0.01).
Dieli-Conwright, Christina M; Sami, Nathalie; Norris, Mary K; Wan, Junxiang; Kumagai, Hiroshi; Kim, Su-Jeong; Cohen, Pinchas · Randomized Controlled Trial (Secondary Analysis)
RPEP-05347 · 2021SS-31 peptide targets mitochondria directly, inhibiting oxidative stress and restoring mitochondrial function with greater therapeutic potential than traditional antioxidants like vitamin E in models of diabetes and Alzheimer's disease.
Ding, Xiao-Wen; Robinson, Megan; Li, Rongzi; Aldhowayan, Hadeel; Geetha, Thangiah; Babu, Jeganathan Ramesh · Review
RPEP-09597 · 2024Marine peptides target multiple aging mechanisms simultaneously — oxidative stress reduction, inflammation modulation, mitochondrial repair, autophagy induction, and longevity pathway regulation — making them promising multi-target anti-aging agents.
Yao, Wanzi; Zhang, Yifeng; Zhang, Gaiping · Review
RPEP-09710 · 2024GLP-1 drugs are effective for weight management in older adults but require careful monitoring for sarcopenia and bone loss, with exercise and nutrition strategies to mitigate risks.
Žižka, Ondřej; Haluzík, Martin; Jude, Edward B · Review