The effects of parenteral or dietary omega-3 polyunsaturated fatty acids in rat models of spinal cord injury
There is currently no effective treatment for spinal cord injury (SCI). Long chain omega-3 polyunsaturated fatty acids (PUFA) such as docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) have beneficial effects in various neurological disorders. DHA and EPA have neuroprotective effects when given intravenously (i.v.) after SCI, but dietary enrichment with these fatty acids is less well-characterized. It is important to characterize the effect of these compounds after parenteral and oral administration, as both regimes could be used clinically. The aims of this thesis were to: i) characterize the inflammatory response in the rat after T12 compression SCI, ii) characterize the effects of acute i.v. injection of DHA or EPA on inflammation after SCI, iii) explore the effects of i.v. DHA in a rat contusion model of SCI, iv) assess the effects of dietary enrichment with DHA or EPA before and/or after SCI. Compression SCI led to acute infiltration of neutrophils and delayed accumulation of macrophages/microglia in the spinal cord, and a systemic inflammatory response in plasma and liver. DHA i.v. injection reduced neutrophil infiltration to the epicentre and C-reactive protein in the plasma, whereas EPA had no significant effect. There was no effect of i.v. EPA or DHA on the increase in cytokines/chemokines following injury. Acute DHA restored stepping ability after contusion SCI, but there was no effect on histological markers. Dietary enrichment with EPA after compression SCI had a detrimental effect on recovery, but this was not correlated with changes in neurones, oligodendrocytes or macrophages/microglia. Dietary pre-treatment with DHA had no effect on locomotor outcome after compression SCI. Therefore, the inflammatory response after SCI is not changed significantly by acute administration of EPA and DHA. The study did not reveal a beneficial prophylactic effect of dietary DHA, but highlighted a possible risk associated with dietary EPA after SCI.
AuthorsHall, Jodie Christine Elizabeth
- Theses