Simultaneous quantification of TB-500 and its metabolites in in-vitro experiments and rats by UHPLC-Q-Exactive orbitrap MS/MS and their screening by wound healing activities in-vitro.
Level 5 - mechanism / opinion, no new human data
Preclinical in vitro and animal pharmacokinetic and cell assay study
PubMed 38382158 · doi:10.1016/j.jchromb.2024.124033
What was done
Researchers developed and validated a UHPLC-Q-Exactive orbitrap MS/MS assay to simultaneously identify and quantify TB-500 (Ac-LKKTETQ) and its metabolites. Metabolism was investigated across human serum, in vitro enzymatic systems, and urine from rats administered TB-500. Cytotoxicity and wound-healing activity of parent TB-500 and its metabolites were evaluated in cultured fibroblasts.
What was found
Ac-LK was the primary metabolite with the highest urinary concentration in rats at 0–6 hour intervals, and Ac-LKK was detected up to 72 hours. Neither the parent compound nor its metabolites demonstrated cytotoxicity. Ac-LKKTE was the only metabolite that showed significant wound-healing activity compared to control. The abstract reports no numerical values for metabolic concentrations or wound-healing rates.
Why it matters
The study establishes an analytical method to quantify TB-500 and its metabolites, providing evidence that wound-healing activity attributed to TB-500 in vitro may be driven primarily by the metabolite Ac-LKKTE rather than the parent peptide.
Limits
Sample sizes for the rat cohorts and cell culture replicates are not stated in the abstract. No quantitative effect sizes, concentrations, or assay statistics are reported. The data are limited to in vitro cell assays and animal urine, without in vivo wound healing or human clinical validation.
Cited by
- partial TB-500 promotes blood flow and tissue repair at injury sites.