Background: The elaboration of biocompatible nerve guide conduits (NGCs) has been studied in recent years as a treatment for total nerve rupture lesions (axonotmesis). Different natural polymers have been used in these studies, including cellulose associated with soy protein. The purpose of this report was to describe manufacturing NGCs suitable for nerve regeneration using the method of dip coating and evaporation of solvent with cellulose acetate (CA) functionalized with soy protein acid hydrolysate (SPAH). Methods: The manufacturing method and bacterial control precautions for the CA/SPAH NGCs were described. The structure of the NGCs was analyzed under a scanning electron microscope (SEM); porosity was analyzed with a degassing method using a porosimeter. Schwann cell (SCL 4.1/F7) biocompatibility of cell-seeded nerve guide conduits was evaluated with the MTT assay. Results: The method employed allowed an easy elaboration and customization of NGCs, free of bacteria, with pores in the internal surface, and the uniform wall thickness allowed manipulation, which showed flexibility; additionally, the sample was suturable. The NGCs showed initial biocompatibility with Schwann cells, revealing cells adhered to the NGC structure after 5 days. Conclusions: The fabricated CA/SPAH NGCs showed adequate features to be used for peripheral nerve regeneration studies. Future reports are necessary to discuss the ideal concentration of CA and SPAH and the mechanical and physicochemical properties of this biomaterial.
The present study analyzed the effects of low-level laser therapy (LLLT) and the purified natural latex protein (Hevea brasiliensis, F1 protein) on the morpho-function of sciatic nerve crush injuries in rats. One-hundred and eight male Wistar rats were randomly allocated to six groups (n = 18): 1. Control; 2. Exposed (nerve exposed); 3. Injury (injured nerve without treatment); 4. LLLT (injured nerve irradiated with LLLT (15 J/cm2, 780 nm)); 5. F1 (injured nerve treated with F1 protein (0.1%)); and 6. LLLT + F1 (injured nerve treated with LLLT and F1). On the 1st, 7th, 14th, and 56th days after injury, a functional sensory analysis of mechanical allodynia and mechanical hyperalgesia and a motor analysis of grip strength and gait were performed. After 3, 15, and 57 days, the animals were euthanized for morphometric/ultrastructural analyses. The treatments applied revealed improvements in morphometric/ultrastructural parameters compared to the injured group. Sensory analyses suggested that the improvements observed were associated with time progression and not influenced by the treatments. Motor analyses revealed significant improvements in grip strength from the 7th day in the LLLT group and in gait from the 56th day in all treated groups. We concluded that even though the morphological analyses showed improvements with the treatments, they did not influence sensory recovery, and LLLT improved motor recovery.
Peripheral nerve injuries, especially neurotmesis, require precise repair strategies due to their severity and limited capacity for spontaneous regeneration. Nerve guidance conduits (NGCs) offer a promising alternative to autografts; however, consistent surgical techniques and anatomical references in rodent models could be enhanced. This ex vivo study focuses on describing and establishing a standardized, reproducible anatomical and technical protocol for implanting an NGC in the sciatic nerve of Wistar rats, identifying a 7 mm segment free of collateral branches as a safe site for neurotmesis. Thirty cadaveric hind limbs were positioned in lateral decubitus, and anatomical landmarks such as the greater trochanter, ischial bone, and femoral condyle guided the incision. A 1 cm scaffold was inserted and secured with 8-0 absorbable sutures, while muscle and skin were closed with 5-0 and non-absorbable sutures. The technique enabled safe access to the nerve, minimized risk to adjacent structures, and ensured proper scaffold positioning without tension. This standardized approach improves surgical reproducibility and supports anatomical integrity; however, because the study used ex vivo cadaveric samples, its capacity to facilitate functional nerve regeneration remains theoretical. While the protocol emphasizes the importance of surgical planning and suture patterns, it cannot account for active biological processes such as angiogenesis, inflammatory response, or axonal growth, which are critical for successful repair. Ultimately, this study provides a reliable anatomical platform for NGC evaluation under controlled experimental conditions, serving as a necessary precursor to in vivo validation of safety and functional outcomes.