Essential fatty acid-rich diets protect against striatal oxidative damage induced by quinolinic acid in rats

Abstract

Essential fatty acids have an important effect on oxidative stress-related diseases. The Huntington's disease (HD) is a hereditary neurologic disorder in which oxidative stress caused by free radicals is an important damage mechanism. The HD experimental model induced by quinolinic acid (QUIN) has been widely used to evaluate therapeutic effects of antioxidant compounds. The aim of this study was to test whether the fatty acid content in olive- or fish-oil-rich diet prevents against QUIN-related oxidative damage in rats. Rats were fed during 20 days with an olive- or a fish-oil-rich diet (15% w/w). Posterior to diet period, rats were striatally microinjected with QUIN (240 nmol/µl) or saline solution. Then, we evaluated the neurological damage, oxidative status, and gamma isoform of the peroxisome proliferator-activated receptor (PPARγ) expression. Results showed that fatty acid-rich diet, mainly by fish oil, reduced circling behavior, prevented the fall in GABA levels, increased PPARγ expression, and prevented oxidative damage in striatal tissue. In addition none of the enriched diets exerted changes neither on triglycerides or cholesterol blood levels, nor or hepatic function. This study suggests that olive- and fish-oil-rich diets exert neuroprotective effects.

Keywords:

• Essential fatty acids
• Olive oil
• Fish oil
• Oxidative damage
• Huntington's disease

Acknowledgments

The authors thank Q.F.B. Miguel Galicia Toledo, Q.F.B. Porfirio Valle Márquez, and Rolando Dominguez Pérez for invaluable technical support and laboratory assistance. This study was supported by Consejo Nacional de Ciencia y Tecnología (CONACYT) Research grant #241911 to F. Pérez-Severiano.

Disclaimer statements

Contributors

All authors had full access to all the data in the study and take responsibility for the integrity of the data and the accuracy of the data analysis. A.M.-M., A.S.-M., and F.P.-S. designed the research; J.B.P.-F., J.C.M.-L., P.E.M.-G., M.E.-H., I.P.-N., N.C., and L.T.-L. conducted the research; S.M., A.Z.-C., and C.R. performed statistical analysis. F.P.-S. wrote the manuscript and had primary responsibility for the final content.

Funding

None.

Conflicts of interest None of the authors had any financial or personal conflict of interest to declare.

Ethics approval

All animal care and experimental procedures were performed in compliance to the National Institutes of Health Guide for Care and Use of Laboratory Animals (Publication No. 85-23, revised 1985) and the Guidelines on Ethical Standards for Investigation of Experimental Pain in Animals and were approved by our local Ethics Committee (Instituto Nacional de Neurología ‘Manuel Velasco Suárez’ Mexico City, protocol 74/12). In addition, every effort was made to minimize animal pain and suffering. A minimal number of rats were used to obtain statistical significance.