Brain-derived neurotrophic factor-based therapies in peripheral nerve injury-a systematic review of animal studies

Peripheral nerve injuries (PNIs) remain a significant clinical problem, producing permanent motor-sensory deficits and diminishing patient's quality of life. Neurotrophic growth factors, a family of biomolecules, support neuronal survival and regeneration. Among them, Brain-Derived Neurotrophic Factor (BDNF) emerged as a key modulator of neurogenesis and neuroregeneration within the peripheral nervous system. This systematic review evaluates and summarises animal-based evidence on BDNF-based therapies used in peripheral nerve injury (PNI). A literature search in PubMed, EMBASE, Scopus, and Web of Science with the latest results from 10th of October 2024 to identify animal-based studies evaluating the effects of BDNF-based therapies used in PNI. Of 785 records, 40 articles met the inclusion criteria, encompassing 1887 rats and 430 mice or rabbits across various injury models. Gathered studies heterogenicity precluded meta-analysis, but most reports showed superior axonal regeneration, myelination, and functional recovery in BDNF-based therapies compared to control groups. The benefits were most significant with multimodal strategies, including multiple neurotrophins and stem cells. Combined therapies involving multiple neurotrophic growth factors, BDNF, and stem cell therapies showed the most significant improvement in functional outcomes and histological parameters of injured nerves. These results suggest that BDNF-based therapies hold promise for effective PNI treatment.