Fig. 4.

An in situ forming hyaluronic acid hydrogel with reactive oxygen species-scavenging activity by inhibiting oxidative stress and neuroinflammation in traumatic brain injury (TBI) repair. a) Schematic showing neural functional repair in TBI model by hyaluronic acid-tyramine combined with gallic acid-grafted hyaluronic acid (HT/HGA) hydrogel injection by removing free radicals and changing microglial polarization from M1 (pro-inflammatory phenotype) to M2 (anti-inflammatory phenotype). Neurogenesis and brain tissue remodeling were observed after 21 days of treatment by b) western blot, c) relative gene expression of NFL, NSE, NeuN, β-III tubulin, and d) imaging of TBI mice brain and hematoxylin and eosin stain (H&E) staining. e) Lesion volume of the TBI mice brain. f) Immunofluorescence staining (IF) of Ki67 and NeuN. The learning and memory abilities were assessed via the Morris water maze (MWM) behavior test, including g) swimming trails, h) escape latency, i) time in the target zone (I quadrant), j) the number of site crossings [213]. Copyright 2022 Elsevier.