Histological analysis of Spinal Cord Injury treated with Amniotic Membrane

Spinal cord injury (SCI) is one of the most harmful syndromes that affects humans due to neuronal destruction and interruption of the nerve impulse transmission between axons. The conduction of motor, sensory, and autonomic responses below the level of the injury is seriously compromised, generating high treatment costs for the health system and a reduction in quality of life, stimulating research into new treatment protocols. This study aimed to evaluate the effectiveness of a biomaterial, the amniotic membrane (AM), to treat experimentally induced SCI. 15 adult rats were divided into three groups (n = 5): S (Sham), L (SCI without treatment), and AM (SCI treated with AM). Spinal cord injury was induced in the region T9-T10 by direct trauma, free-falling a weight (10 g, 2 mm flat edge) held on a mini guillotine, 25 mm above the exposed spinal cord. A fragment of AM, obtained from the human placenta after maternal consent, was applied to the injured area only in the AM group. After 28 days, specimens from the area of spinal cord injury were excised and subjected to routine histological procedures. Data from the semi-quantitative score, obtained from a scheme that assigned different scores to regions of the spinal cord, and from the quantitative analysis were subjected to parametric statistical analysis. Results showed that Group S presented medullary tissue without changes (score 0). In contrast, Group L presented numerous areas of cavitation in the dorsal and lateral regions of the white and gray matter (9.61 ± 6.60 p<0.001) with an intense inflammatory infiltrate. The AM group exhibited small areas of cavitation in the dorsal and lateral regions of the white matter and part of the dorsal columns in the gray matter (0.94 ± 1,03, p<0.001), with few inflammatory cells. The results suggest the effectiveness of AM in the treatment of induced SCI, characterized by a reduction in the evolution of inflammatory and degenerative processes in the central nervous tissue compared to the untreated group.