Effects of BPC-157 and TB-500 on Achilles tendon healing in rats: A histopathological and biomechanical study

Biçer O, Adanir O, Güleryüz Y, et al. · Joint Diseases and Related Surgery

At four weeks, load to failure separated from control only in the TB-500 arm (median 37.41 N against 26.91 N; adjusted p=0.041); the BPC-157 arm's 37.16 N did not (p=0.389) and the combination's 34.54 N differed from no group. Total Bonar score fell significantly only with TB-500 (4.0 against 9.5; p=0.016), and total Movin score with TB-500 (8.0 against 18.0; p=0.017) and the combination (p=0.040), not with BPC-157 alone (9.5; p=0.601). BPC-157 did reach significance on individual subscores — fibre arrangement, Masson-trichrome collagen staining and Sirius-red type I collagen birefringence — and no comparison between the three treated arms reached significance on any measure, so the combination added nothing over either peptide alone.

Population

32 male Sprague-Dawley rats, 12 weeks old, with Achilles tendon transection and Kessler repair; 8 per group, 4 tendons per group to biomechanics and 4 to histology

Intervention

BPC-157 10 µg/kg/day, TB-500 60 µg/kg/day, or both, i.p. for 30 days from the first postoperative day

Comparator

Vehicle (distilled water) i.p.

Limitations

Four tendons per group per endpoint, a single four-week time point, no functional test, no cross-sectional area (so no stress or modulus), a TB-500 dose taken from the wider thymosin-β4 literature rather than any tendon dose-finding, and no blinding of surgery or dosing. Independent of the Zagreb network; peptides bought from Peptide Sciences; no funding and no conflicts declared.