Published Research
Safety and Efficacy of Approved and Unapproved Peptide Therapies for Musculoskeletal Injuries and Athletic Performance.
Mendias CL, Awan TM — 2026
Peptides are short chains of amino acids with a unique pharmacological niche between small-molecule drugs and large proteins. Their use in sports medicine is rapidly expanding, driven by patient demand for accelerated injury recovery and performance enhancement. While numerous peptide drugs have undergone a rigorous approval process that evaluates both safety and efficacy, a parallel "gray market" of unapproved compounds has emerged, operating largely outside of regulatory oversight. Our objective is to present the pharmacological mechanisms, safety profiles, and regulatory status of prominent approved and unapproved peptides marketed direct to patients, including AOD-9604 (anti-obesity drug 9604), BPC-157 (body protection compound 157), CJC-1295, FS-344 (follistatin-344), GHK-Cu (glycyl-L-histidyl-L-lysine copper), ipamorelin, MOTS-C (mitochondrial ORF of the 12S rRNA type-c), sermorelin, SS-31 (elamipretide), tesamorelin (Egrifta), Tβ4 (thymosin beta-4), and TB-500 (thymosin beta-4 fragment). Many unapproved peptides demonstrate favorable tissue repair and metabolic outcomes in animal models, but rigorous human safety data are scarce, and there is potential for serious harm to patients. This narrative review focuses on the utilization of peptides in sports medicine, and alternative treatments that may be considered. We provide a framework to navigate patient discussions about peptides to better facilitate evidence-based practices for musculoskeletal healing and athletic performance. We also discuss the placebo effect as a mediator of peptide efficacy, and how social media amplifies this effect.
Growth hormone-releasing hormone attenuates amyloid deposition and neuroinflammation in Alzheimer's disease models.
Pedrolli F, Morello G, Gesmundo I, Banfi D, Ferro A, et al. — 2026
Alzheimer's disease (AD) is a progressive neurodegenerative disorder characterized by amyloid-β (Aβ) accumulation, tau hyperphosphorylation, neuroinflammation, and synaptic loss. Existing therapies provide only modest symptomatic relief and fail to slow disease progression. Beyond its role in promoting pituitary growth hormone (GH) secretion, growth hormone-releasing hormone (GHRH) has shown neuroprotective effects in experimental ischemic stroke and spinal muscular atrophy. Here, we explored the therapeutic potential of GHRH and its agonist MR-409 in AD models. In vitro, GHRH(1-44)NH₂ promoted survival, proliferation, and neuronal differentiation of rat hippocampal neural stem cells (NSCs) and human SH-SY5Y neuroblastoma cells under growth factor deprivation and amyloid beta (Aβ) exposure. These effects involved the cAMP/PKA/CREB, ERK1/2, and PI3K/Akt signaling pathways. GHRH also attenuated Aβ-induced neurotoxicity by reducing apoptosis, suppressing GSK-3β activity and tau phosphorylation, restoring nuclear β-catenin, and inhibiting NF-κB-mediated inflammation. In vivo, subcutaneous administration of MR-409 in 5xFAD mice reduced Aβ deposition, tau phosphorylation, gliosis, and proinflammatory cytokine expression. In addition, MR-409 mitigated neuronal and synaptic loss, activated survival and neurogenic pathways, and improved cognitive performance, without altering systemic GH and IGF1 levels. MR-409 also elevated NRF2 mRNA expression while reducing its negative regulator KEAP1. Overall, these findings indicate that GHRH and its analog MR-409 exert neuroprotective effects by modulating key pathological features of AD, including neurodegeneration, impaired neurogenesis, neuroinflammation, and oxidative stress. Given their ability to modulate multiple pathological pathways, GHRH agonists may represent promising therapeutic candidates for AD and other neurodegenerative disorders.
A new era of doping? Use of peptide and peptide-analog drugs in recreational and professional sport and bodybuilding: a critical review.
Coutinho LFD, DE Oliveira Neves LF, Camilo RP — 2026
The pursuit of pharmacological enhancement in sport has evolved from the widespread use of anabolic-androgenic steroids (AAS) to novel agents such as peptides and peptide analogues. Marketed as more selective and ostensibly safer alternatives, peptides-including growth hormone secretagogues (e.g., Ipamorelin), growth hormone-releasing hormone analogues (e.g., CJC-1295, Sermorelin), and synthetic fragments (e.g., Frag 176-191, KPV)-are promoted for muscle growth, fat metabolism, recovery, and anti-inflammatory effects. Their pharmacological profiles, including enhanced stability and receptor selectivity, have made them attractive in both medical research and bodybuilding communities. Despite their growing popularity, the clinical evidence supporting peptide use in sport is limited. Most published studies examine therapeutic applications under controlled dosing regimens, not the supraphysiological or combined protocols common in bodybuilding. Emerging data highlight potential risks: cardiovascular strain, insulin resistance, dyslipidemia, and psychiatric instability. The largely unregulated supply chain exacerbates these dangers, as products are often mislabeled or contaminated. Regulatory bodies such as the World Anti-Doping Agency (WADA) have responded by expanding detection technologies, yet analytical challenges remain due to peptides' structural similarity to endogenous hormones and short half-lives. Beyond elite sport, the extent of peptide use in the general population is unknown. Anecdotal reports and widespread promotion on social media suggest growing uptake among recreational gym-goers, including younger individuals, but prevalence studies are lacking. This represents a critical gap in current knowledge. In conclusion, peptides represent a new phase in performance enhancement but remain experimental substances with poorly defined long-term risks. Until longitudinal data clarify their safety and prevalence, peptide use in both competitive and recreational settings should be considered high-risk and ethically problematic.
Therapeutic Peptides in Orthopaedics: Applications, Challenges, and Future Directions.
Rahman OF, Lee SJ, Seeds WA — 2026
Therapeutic peptides are emerging as promising adjuncts in the management of orthopaedic injuries, grounded in their ability to modulate molecular signaling networks central to cellular medicine. By acting on key pathways such as PI3K/Akt, mTOR, MAPK, TGF-β, and AMPK, peptides exert influence over tissue regeneration, inflammation resolution, and neuromuscular recovery. Wound-healing peptides such as BPC-157, TB-500, and GHK-Cu promote angiogenesis, integrin-mediated extracellular matrix remodeling, and fibroblast activation, whereas growth hormone secretagogues like ipamorelin, CJC-1295, tesamorelin, sermorelin, and AOD-9604 activate IGF-1 signaling and satellite cell repair. Recovery-enhancing agents such as epithalon, delta sleep-inducing peptide, and pinealon target circadian and mitochondrial regulators, and neuroactive peptides like selank, semax, and dihexa enhance brain-derived neurotrophic factor and HGF/c-Met pathways critical to neuroplasticity. Although preclinical studies are promising, there is a current lack of clinical trials. This review integrates current mechanistic insights with orthopaedic relevance, emphasizing safety, efficacy, and future directions for responsible integration into musculoskeletal care.
Analysis of growth hormone releasing hormone and its analogs in urine using nano liquid chromatography coupled with quadrupole/orbitrap mass spectrometry.
Uçaktürk E, Nemutlu E — 2026
Growth hormone-releasing hormone (GHRH) and its synthetic analogs are considered performance-enhancing substances and are therefore prohibited by the World Anti-Doping Agency (WADA). The analysis of GHRH and its analogs in urine presents significant analytical challenges due to their inherent in vivo instability, rapid renal clearance, and low urinary concentrations. The present study aimed to develop a robust nano-LC quadrupole/orbitrap mass spectrometry (nano-LC-Q/Orbitrap MS) method for both screening and confirmation analyses of GHRH and its synthetic analogs (sermorelin/CJC-1293, tesamorelin, and CJC-1295) and the primary metabolite of sermorelin in urine, in accordance with WADA requirements. The sample preparation workflow was systematically investigated. Existing solid-phase extraction (SPE) protocols were compared, and two additional commercially available SPE cartridges were evaluated. Within the SPE step, the influence of various washing and elution solvent strengths on peptide recovery was also systematically examined. The effectiveness of different cleanup solvents during the ultrafiltration step was further assessed. Based on these evaluations, a refined approach was developed, incorporating an initial ultrafiltration step followed by SPE. The proposed method was fully validated according to WADA guidelines, assessing key parameters such as selectivity, reliability, limits of detection (LOD), carryover, limits of identification (LOI), robustness, autosampler stability, and matrix effects. The validation results confirmed the method's suitability and robustness for anti-doping testing. Achieved LODs (≤ 0.5 ng/mL) and LOIs (0.5-0.75 ng/mL) demonstrated sufficient sensitivity for effective detection and confirmation analysis of the target peptides in urine.