Eugenol and its association with levodopa in 6‐hydroxydopamine‐induced hemiparkinsonian rats: Behavioural and neurochemical alterations

Abstract

Parkinson's disease is a neurodegenerative disorder that affects the central nervous system and is mainly characterized by the loss of dopaminergic neurons and pro‐oxidant mechanisms. Eugenol has been widely studied due to its anti‐inflammatory and antioxidant activities, making it a promising neuroprotective agent. This study aimed to investigate the effects of eugenol and its combined action with levodopa in the 6‐hydroxydopamine‐induced Parkinson's disease model. Wistar rats were subjected to intrastriatal injection of 6‐hydroxydopamine (21 μg) and then treated with eugenol (0.1, 1, or 10 mg/kg), levodopa (25 mg/kg) or their combination (eugenol 10 mg/kg + levodopa 12.5 mg/kg) orally for 14 days. On the 14th day, the animals were subjected to behavioural tests, and after euthanization and dissection of the brain areas, neurochemical analyses were performed. The results showed that eugenol reduced the oxidative stress and behavioural disturbances induced by 6‐hydroxydopamine. The eugenol and levodopa combination was more effective in some behavioural parameters and body‐weight gain in addition to promoting an increase in reduced glutathione levels compared to levodopa alone. Thus, the neuroprotective activity of eugenol was observed against motor and neurochemical disorders. Additionally, the eugenol and levodopa combination was promising when compared to conventional treatment.

Protective effects of functional foods against Parkinson's disease: A narrative review on pharmacology, phytochemistry, and molecular mechanisms

“…Eugenol treatment (1 and 10 mg/kg p.o. ; for 14 days) significantly attenuated oxidative stress and behavioral dysfunction (Moreira Vasconcelos et al, 2020).…”

“…Overall, clove oil may protect against PD by attenuating oxidative stress (Moreira Vasconcelos et al, 2020).…”

Bidirectional Optogenetic Modulation of the Subthalamic Nucleus in a Rodent Model of Parkinson’s Disease

“…L-dopa (25 mg/kg, methyl L-dopa hydrochloride; #D1507, Sigma-Aldrich) and benserazide (10 mg/kg, benserazide hydrochloride; # B0477000, Sigma-Aldrich) (1 ml/kg; i. p . ), 20 min prior to test session similar to Moreira Vasconcelos et al (2020) .…”

Pharmacokinetic and Permeation Studies in Rat Brain of Natural Compounds Led to Investigate Eugenol as Direct Activator of Dopamine Release in PC12 Cells

“…To summarize, the goals of this study were to define ( i ) the pharmacokinetic profile of eugenol, cinnamaldehyde and D-limonene following their intravenous administration to rats; ( ii ) the bioavailability of these compounds after their oral administration (as they are or formulated); ( iii ) their aptitude to permeate in CSF from the bloodstream, by evaluating the ratio (R) of their concentration between CSF and the blood of rats at same times after administration; finally, ( iv ) we tried to analyze the possible effects of the EO components that easily permeate into the brain by studying in vitro their potential direct effect on cell viability and dopamine release. It is indeed known that EO components can exert neuroprotective effects on rat models of Parkinson’s disease (PD) [ 16 ]. Therefore, we used PC12 cell line, a cellular model recognized as suitable to mimic dopaminergic neurons [ 17 ], to evaluate the ability of EO components to modulate dopamine release.…”