NEW YORK (Reuters Health) Dec 26 - A polymer hydrogel has the ability to enhance functional recovery to some degree, and tissue reconstruction, in a rat model of chronic spinal cord injury (SCI), investigators report.

NeuroGel is a water-saturated cross-linked hydrophilic copolymer of N-2-(hydroxypropyl) methacrylamide which contains interconnected pores and has viscoelastic properties.

Dr. Stéphane Woerly, of Organogel Canada Ltée in Quebec City, Canada, and colleagues induced a compression injury of the ventral spine in 16 adult rats. As reported in the December 15th issue of the Journal of Neuroscience Research, 14 weeks later the rats exhibited maximal deficit. NeuroGel implants were placed in the injured area of eight rats, seven of which were placed in an enriched environment with other animals and exercise equipment.

The Basso, Beattie & Bresnahan (BB Locomotor Rating Scale improved significantly from 4.5 before implant placement to 5.44 at approximate 5 to 7 months post-implantation (p < 0.01) in those in the enriched environment. The post-treatment BBB scores were significantly different between the controls and the implanted animals (p = 0.02). However, Combined Behavioral Scores showed no improvement.

Seven months after the reconstructive surgery, neural tissue that included myelinated axons and dendro-dendritic contacts had formed within the polymer gel. Wallerian degeneration was inhibited compared to the control animals.

While the functional improvements seen were small, "In a person afflicted with SCI these changes could make a big difference in quality of life," Dr. Woerly and colleagues write. Greater joint mobility could ease the tasks of caregivers, allow the patient to be placed in a wheelchair, and permit physical therapy designed to develop muscular strength.

J Neurosci Res 2001;66:1187-1197.

Comentario

Es muy interesante el trabajo desarrollado por el dr Woerly de Quebec, Canada, en el cual demuestra, en forma por demás objetiva, una recuperación parcial, en ratas adultas con compresión medular crónica ,hasta obtener un avance de 0.9 puntos en la escala de función locomotora de Basso, Beattie y Bresnahan (BBB locomotor rating scale), con una p< 0.01 en comparación con controles.

Dicho avance, como se especifica, se refiere a movilidad de articulaciones en general (por supuesto sin vencer gravedad). Pero ya con movilidad de articulaciones, se puede mejorar la calidad de vida de un paciente pléjico, y además, se facilita la rehabilitación de potencia muscular.

Continúa dicho estudio hasta probarse en humanos( el copolímero prácticamente es atóxico, y sobre todo, no es de origen biológico, lo cual facilitará aun más su administración).

Nos llama la atención , que dicho copolímero inhibe la degeneración Walleriana, lo cual aun no tiene una explicación muy clara. Por otro lado, estos resultados son en modelos animales con compresión medular crónica. Habrá que esperar resultados tambien en lesión medular traumática aguda. Ref Bibl : J Neurosci Res 2001; 66 : 1187 - 1197

Dr Hugo Navarrete

Hospital Excel, Tijuana, B.C.
Grupo de Estudio de Demencias de la Academia Mexicana de Neurología

hugon@telnor.net