Background: This is a novel rat study using native peptide therapy, focused on reversing quadriceps muscle-to-bone detachment to reattachment and stable gastric pentadecapeptide BPC 157 per-oral therapy for shared muscle healing and function restoration. Methods: Pharmacotherapy recovering various muscle, tendon, ligament, and bone lesions, and severed junctions (i.e., myotendinous junction), per-oral in particular (BPC 157/kg/day 10 µg, 10 ng), provides muscle-to-bone reattachment after quadriceps muscle detachment, both complete (rectus muscle) and partial (vastus muscles). Results: Immediately post-injury, and at 1, 2, 3, 5, 7, 14, 21, 28, 60, and 90 days post-injury, quadriceps muscle-to-bone detachment showed definitive healing failure (impaired walking and permanent knee flexure). Contrarily, macro/microscopic, ultrasonic, magnetic resonance, biomechanical, and functional assessments revealed that BPC 157 therapy recovering effects for all time points were consistent. All parameters of the walking pattern fully improved, and soon after detachment and therapy application, muscle approached the bone, leaving a minimal gap (on ultrasonic assessment), and leg contracture was annihilated. The healing process occurs immediately after detachment from both sides: the muscle and the bone. The reattachment fibers from the ends of the muscle could be traced into the new bone formed at the surface (note, at day 3 post-detachment, increased mesenchymal cells occurred with periosteum reactivation). Consequently, at 3 months, the form was stable, and the balance between the muscle and bone was the following: well-organized bone, newly formed as more cortical bone providing a narrower bone marrow space, and the muscle and mature fibers were oriented parallel to the bone axis and were in close contact with bone. Conclusions: Therefore, to achieve quadriceps muscle-to-bone reattachment, the BPC 157 therapy reversing course acts from the beginning, resolving an otherwise insurmountable deleterious course.

As a novel theoretical and practical advantage, preclinical to clinical evidence, this systematic review of PRP, growth factors, and stable gastric pentadecapeptide BPC 157 efficacy in complex musculoskeletal and junctional injuries emphasizes the cytoprotection concept, healing to restore tissue integrity. Notably, the concept holds tendon, ligament, and muscle healing, in particular. Then, it holds their healing together as interconnected lesions. Consequently, this review presents the possibilities for cytoprotective therapies suited for tendon/ligament/muscle and recovery of osteotendinous, myotendinous, and the muscle-to-bone junction. The estimated key was the success of injury recovery amid each agent’s direct exogenous administration, alone or with a carrier, locally or systemically, without reliance on complex scaffolds, carriers, or tissue-engineering constructs. As reviewed, while with commonly acknowledged physiological significance, and acting throughout cytoprotection principles, growth factors (PDGF, TGF-β1, IGF-1, FGF, VEGF, BMPs) delivered locally with various carriers improve tendon, ligament, and muscle healing; however, some (PDGF, TGF-β1, IGF-1) may fail in muscle lesions, and all show limited or no efficacy in junctional healing. Contrarily, proposed as a cytoprotection mediator, BPC 157 acts alone with a full cytoprotection range, given systemically or locally. Moreover, without any carrier, BPC 157 acts alone, combining beneficial effects on tendon, ligament, and muscle injuries with osteotendinous, myotendinous, and muscle-to-bone healing. In rat studies, across systemic (intraperitoneal, intragastric, or drinking water) and local (cream) administration, BPC 157 consistently demonstrated efficacy, indicating considerable translational potential. Further clinical studies will strengthen cytoprotective therapy and, particularly, BPC 157 in complex musculoskeletal and junctional injuries.