Abstract

Rosmarinus officinalis L. is one of the most commonly used plants in traditional medicine. It is characterised by hepatoprotective and antioxidant activities that can be attributed to its hydroxyphenolic components, including rosmarinic acid, carnosol and flavonoids. It has also been reported to have neuroprotective effects. The aim of this study was to determine the effect of R. officinalis L. treatment on the expression of the glutamate transporter (GLT-1) and on neuronal damage in the frontal cortex of rats with hepatic damage that was induced by carbon tetrachloride (CCl₄). The protective effect of R. officinalis L. against hepatic damage induced by CCl₄ was evaluated in Wistar rats that were treated with R. officinalis L. extract one week prior to, and then during chronic treatment with CCI₄. GLT-1 expression was determined using a reverse transcriptase-polymerase chain reaction (RT-PCR), and the morphological features of irreversibly damaged cells in the cerebral cortex were studied using light microscopy. The morphological evaluation of the frontal cortex showed that R. officinalis L. exerted a protective effect that was correlated with increased GLT-1 expression. The protective effect of R. officinalis L. against CCl₄-induced hepatic damage may be due to improved hepatocellular function. Moreover, the presence of antioxidant-containing flavonoids in the extract may contribute to a probable mechanism for this effect.

Key words: Hepatic damage, neuronal damage, frontal cortex, glutamate transporter (GLT-1), Rosmarinus officinalis L.

Abbreviation

GLT-1, Glutamate transporter; CCl₄, carbon tetrachloride; RT-PCR,reverse transcriptase-polymerase chain reaction; GDH, glutamate dehydrogenase; GS,glutamine synthetase; RT, reverse transcription; ANOVA, analysis of variance.