Thyme and Basil Essential Oils Attenuate Hydrogen Peroxide-induced Hepatic Damage in Rats

Background Excessive levels of oxidative radicals injure organs by directly reacting with macromolecules [proteins, lipids, and deoxyribonucleic acid (DNA)]. Antioxidant supplements with compounds rich in antioxidants, such as essential oils, combat oxidative radicals. Objectives This investigation aimed to assess the theory that supplementation with thyme essential oil (TEO) and basil essential oil (BEO) lessen the harmful consequences of hepatic oxidative stress that occur when hydrogen peroxide (H 2 O 2 ) is added to drinking water. Materials and Methods Rats were randomly divided into four groups: normal control (NC) received a basal diet; positive control (PC) was intraperitoneally injected with a single dose of 3% H 2 O 2 ; and TEO or BEO groups were PC groups received 200 mg/kg of TEO or BEO for 30 days. Results BEO demonstrated a higher capacity for radical scavenging than TEO in 2,2-diphenyl-1-picrylhydrazyl (DPPH) and H 2 O 2 assays. Treatment with BEO and TEO significantly improved various liver functions, including total protein, total bilirubin, albumin, and liver enzymes [alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transferase (GGT), and alkaline phosphatase (ALP)] with BEO preferred over TEO. TEO and BEO administration significantly reduced oxidative stress and inflammation by lowering malondialdehyde (MDA) values and enhancing superoxide dismutase (SOD), glutathione peroxidase (GPx), and catalase (CAT) activities, and maintaining normal levels of myeloperoxidase (MPO) and nitrite production in H 2 O 2 -treated rats. TEO and BEO also repaired the deformed liver structure to the normal. Conclusion These results provide critical insight into how thyme and basil essential oils might protect the liver from H 2 O 2 -induced oxidative stress and inflammation.