A Possible Anti-Inflammatory Effect of Proline in the Brain Cortex and Cerebellum of Rats.

Although many studies show the toxic effects of proline, recently it has been reported some anti-inflammatory effect of this amino acid. Our principal objective was to investigate the effects of proline on the alterations caused by LPS (lipopolysaccharide) administration in the cerebral cortex and cerebellum of young Wistar rats. The animals were divided into four groups: control (0.85% saline); proline, (12.8 μmol of proline/g body weight from day 7 to 13; 14.6 μmol of proline/g body weight from day 14 to 17 and 16.4 μmol of proline/g body weight from day 18 to 21); LPS (1 mg/g body weight); LPS plus proline. The animals were killed at 22 days of age, 12 h after the last injection, by decapitation without anesthesia. The brain cortex and cerebellum were separated for chemical determinations. The effects of proline and LPS in the cerebral cortex and cerebellum on the expression of S100B and GFAP, oxidative stress parameters, enzymes of phosphoryl transfer network activity, and mitochondrial respiration chain complexes were investigated. Two-way ANOVA showed that the administration of proline did not alter the analyzed parameter in cerebral cortex and cerebellum. On the other hand, LPS administration caused a change in these parameters. Besides, the co-administration of proline and LPS showed the ability of Pro in preventing the effects of LPS. These results indicated that LPS induces inflammation, oxidative stress, and alters energy parameters in cerebral cortex and cerebellum of the rats. Moreover, co-administration of Pro was able to prevent these harmful effects of LPS.