Background: Neurotmesis leads to neuromuscular junction (NMJ) degeneration, muscle atrophy, and functional loss. While neurorrhaphy is standard, motor recovery is often incomplete. Heterologous fibrin biopolymer (HFB) shows potential as an adjunct, hence, we investigate HFB's late regenerative effects.
Material/methods: Twenty adult male Wistar rats (CEUA-FMB 1402/2021) were divided into Control (C), Denervated (D), Neurorrhaphy (N), and Neurorrhaphy + HFB (NB) groups. After 120 days, nerves and muscles were analyzed.
Results: NB (1355 ± 170.4) showed more intact axons than C (927 ± 170.4, p = .0026) and N (774 ± 158.2, p = .0002). NMJ morphology in NB was closer to C than N, with increased nAChR alpha-1 (NB vs. N p = .0428; NB vs C p = .0084) and Rapsyn (NB vs. N p = .0130; NB vs C p = .0053) expression. Muscle integrity in NB resembled C, exhibiting less atrophy (area: C vs. N p = .0002; NB vs. N p = .0117; perimeter: C vs. N p = .0002; NB vs. N p = .0114; central nuclei: C vs. N p = .0009; NB vs. N p = .0110) and fibrosis (C vs. N p = .0061; N vs. NB p = .0326) compared to N.
Conclusion: HFB associated with neurorrhaphy enhanced muscle and nerve regeneration, attenuating muscle atrophy and fibrosis.
Keywords: Neurorrhaphy; degeneration; fibrin sealant; peripheral nerve injury; regenerative medicine.
When a nerve is completely cut, it can really limit how people can move and take care of themselves, making their lives much harder. Doctors usually try to fix this by sewing the cut ends of the nerve back together. But often, people don’t fully recover their movement, so we need better treatments. This research looked at using a special biological glue called heterologous fibrin biopolymer (HFB) to help nerves heal better after they’ve been sewn back together. In this study, we saw that after four months, using HFB along with the usual nerve sewing created a better place for the nerve to regrow compared to just sewing the nerve alone, as this association led to healthier nerve and muscle regeneration. Our findings suggest that HFB has good long-term benefits for fixing damaged nerves, which consequently prevents severe cases of atrophy and muscle degeneration. This makes HFB a promising material that could be used in hospitals to help people with nerve injuries recover better.