In vitro
This cell-culture study investigated whether the endogenous tripeptide Lysine-Proline-Valine (KPV), derived from α-melanocyte-stimulating hormone, could protect liver cells from fat accumulation. Using the human hepatocellular carcinoma cell line HepG2, researchers induced a hepatic steatosis model by exposing cells to oleic acid (OA), which mimics lipid overload seen in non-alcoholic fatty liver disease (NAFLD). The study found that OA treatment increased intracellular lipid deposits and upregulated fatty acid synthase (FAS), a key enzyme in fat production. KPV treatment was reported to attenuate these effects without causing cytotoxicity. Mechanistically, the authors propose that KPV reduced reactive oxygen species (ROS), which in turn blunted activation of ERK, reduced AKT/mTORC1 phosphorylation, and normalized phosphorylation of PPARγ — a transcription factor central to de novo lipogenesis — ultimately suppressing FAS expression. The study is limited to a single in vitro cell line model, with no animal or human data, meaning findings cannot yet be extrapolated to living organisms. Concentrations used in cell culture do not translate directly to physiological dosing. Results are hypothesis-generating and require further validation in vivo.
Cytotechnology · Apr 2026DOI ↗ Review
This critical review examines the emerging use of peptides and peptide analogues as performance-enhancing drugs in both competitive sport and recreational bodybuilding. The authors survey a range of compounds — including growth hormone secretagogues (e.g., Ipamorelin), growth hormone-releasing hormone analogues (e.g., CJC-1295, Sermorelin), and synthetic peptide fragments (e.g., Frag 176-191, KPV) — which are promoted in bodybuilding communities for purported benefits in muscle growth, fat loss, recovery, and anti-inflammation. The review notes that these compounds are attractive partly due to their enhanced receptor selectivity and stability compared to older anabolic agents. However, the authors conclude that clinical evidence supporting their use in sport contexts is limited; most existing research addresses therapeutic applications under controlled medical settings, not the high-dose or stacked protocols typical in bodybuilding. The review identifies potential risks including cardiovascular strain, insulin resistance, dyslipidemia, and psychiatric instability. It also highlights the dangers posed by an unregulated supply chain prone to mislabeling and contamination. Anti-doping detection remains challenging due to peptides' structural similarity to endogenous hormones and short half-lives. A key gap identified is the near-complete absence of population-level prevalence data, particularly for recreational users. The authors characterize peptide use in sport as high-risk and ethically problematic pending longitudinal safety evidence.
The Journal of sports medicine and physical fitness · Mar 2026DOI ↗ Review
This comprehensive review synthesizes research published between 2016 and 2025 on the role of tripeptides in wound healing and skin regeneration. The authors examine how these short, three-amino-acid peptides regulate critical repair processes including cell migration, proliferation, and differentiation, as well as inflammation modulation, angiogenesis promotion, and extracellular matrix (ECM) remodeling. The review highlights several specific tripeptides: GHK-based formulations (including nanoparticle conjugates, hydrogels, and clinical derivatives TriHex and TriHex 2.0) were found in cited studies to enhance fibroblast migration, collagen and elastin synthesis, ECM remodeling, and wound closure with added antimicrobial activity. KdPT was reported to mitigate hyperglycemia-induced oxidative stress and restore keratinocyte function, while KPV-loaded hydrogels reduced inflammation and combated MRSA infections. Lipotripeptides (DICAMs) were noted to inhibit and disrupt bacterial biofilms, and GPE was associated with neuroprotection via ERK and PI3K/Akt signaling. The review also addresses physicochemical comparisons with larger peptides, biomaterial scaffold integration, and emerging applications in cancer and cosmetics. As a narrative review, it does not generate new experimental data. Key limitations include inherent selection bias and the predominance of preclinical evidence in the underlying literature. The authors call for further research into stability, bioavailability, and delivery optimization.
International journal of medical sciences · Oct 2025DOI ↗ Preclinical
This study investigated how dysregulation of the NLRP3 inflammasome in melanocytes contributes to vitiligo pathogenesis. Using skin samples from vitiligo patients and a melanoma-Treg-induced vitiligo mouse model, the researchers found that NLRP3 expression is significantly elevated in vitiligo melanocytes. Mechanistically, they identified that decreased expression of the E3 ubiquitin ligase β-TrCP1 in vitiligo melanocytes reduces K27-linked ubiquitination of NLRP3, weakening its interaction with the autophagy receptor NDP52. This disrupts selective autophagic clearance of NLRP3, allowing it to hyperactivate inflammatory and pyroptotic pathways—including GSDMD pore formation and IL-1β release—ultimately destroying melanocytes. Genetic knockout of NLRP3 in mice alleviated vitiligo progression. As a potential therapeutic approach, the authors developed lysine-proline-valine (KPV)-modified deformable liposomes carrying Nlrp3 shRNA, which achieved melanocyte-targeted NLRP3 knockdown and reduced vitiligo development in mice. Key limitations include reliance primarily on a mouse model, limited human mechanistic validation, and the therapeutic intervention being tested only in animals, leaving clinical translation unestablished.
Cell death and differentiation · Sep 2025DOI ↗