Virgin olive oil has demonstrated its effective activity against oxidative stress. However, data on the bioactive effect of olive leaves or their major constituents on the liver are scarce. The present research work was conducted to evaluate the hepatoprotective effects of supercritical carbon dioxide (SC-CO₂) extracts from fresh and dried olive leaves on hepatotoxicity caused by carbon tetrachloride (CCl₄) in rat models. For this purpose, healthy albino rats of 180–250 g weight were used. The assessment of biochemical markers was carried out on blood and liver tissue. Then, a histopathological study was carried out on liver tissue. The obtained results showed that fresh and dried olive leaf extracts ameliorate the perturbed biochemical parameters caused by CCl₄ treatment. Furthermore, the results registered for the histopathological study are in accordance with the biochemical parameters and the protective capacity of SC-CO₂ extracts against DNA damage, indicating that olive leaf extracts helped to improve liver fibrosis caused by CCl₄ treatment.

In recent decades, the use of herbs and plants has been of great interest, as they have been the sources of natural products, commonly named as bioactive compounds. In specific, the natural compounds from the Capparaceae family which has been proved to have antioxidant, anti-inflammatory, antimicrobial and anti-carcinogenic activities, by several studies. Cleome arabica L. (CA) specie is the most used medicinal plants in Tunisia and elsewhere in North African countries for treatment of various diseases including diabetes, rheumatism, inflammation, cancer, and digestive disorders. The current work was undertaken to estimate the total phenolic, flavonoid and condensed tannin contents, to identify and quantify the polyphenolic compounds, and to evaluate the antioxidant and the anti-inflammatory proprieties of CA fruits extract against formalin induced chronic inflammation in Female Wistar rats. In fact, the antioxidant activity was tested by Diphenyl-1-Picrylhydrazyl free radical scavenging (DPPH), Ferric reducing antioxidant power (FRAP) and Nitric Oxide radical (NO·). Anti-inflammatory effect of fruits extract was examined using formalin (2%) induced paw edema in rats. Molecular docking tools were used to investigate the interaction of some compounds from CA fruits extract with the cyclooxygenase-2 (COX-2) target protein. Our results showed that, the total phenolic, flavonoid and tannins contents, which were assessed by the Folin-Ciocalteu, Quercetin, and Catechin methods, respectively, were 230.22 mg gallic acid equivalent/g dry weight (mg GAE/g DW), 55.08 mg quercetin equivalent/g dry weight (QE/g DW) and 15.17 mg catechin equivalents/g dry weight (CatE/g DW), respectively. HPLC analysis revealed the presence of five polyphenolic compounds whose catechin was found to be the most abundant compounds. The antioxidant activity of extract was quantified by DPPH, FRAP and NO· tests and IC₅₀ reached the values of 3.346 mg/mL, 2.306 and 0.023 mg/mL, respectively. Cleome fruits ameliorated the histological integrity of the skin and alleviated the disruptions in hematological parameters (WBC, LYM, RBC, and HGB), inflammatory cytokines (IL-1β, IL-6, TNF-α), C-reactive protein, and some oxidative stress markers (TBARS (−49%) and AOPP (−42%) levels, SOD (+33%) and GPx (+75%) activities, and GSH (+49%) content) induced by formalin injection. Moreover, the in-silico investigation had shown that CA fruits extract compounds have a stronger interaction with COX-2 active site, more than the reference drug “indomethacin” (two H-bonds). Our research gives pharmacological backing to the healthcare utilization of Cleome plant in the treatment of inflammatory diseases and oxidative harm.

This study aimed to investigate the potential effects of melatonin on aluminium-induced toxicity in a rat model using a set of biochemical, inflammatory, oxidant, lipid profile criteria and hepatic integrity (verified by hematoxylin-eosin staining). The results indicated that AlCl3 administration during 60 days (100 mg/kg b.w.) significantly increased the activities of transaminases AST and ALT by 46% (p < 0.001) and 21% (p < 0.01), lactate dehydrogenase (LDH) by 30% (p < 0.001), the levels of bilirubin by 85% (p < 0.001), total cholesterol by 115% (p < 0.001), triglycerides by130% (p < 0.001), LDL-cholesterol by 413% (p < 0.001), oxidized LDL (oxLDL) by 51% (p < 0.01) and apolipoprotein B100 (apoB100) by 63% (p < 0.001), as compared to controls. The inflammatory markers (TNF-alpha, IL-2, and IL-6) were significantly increased (p < 0.001), associated to higher lipid peroxidation (TBARS) level. Also, both plasma HDL-cholesterol level and hepatic LDL receptors (p < 0.01) expression and antioxidant protein (SOD, CAT, and GPx) activities are decreased. Those physiological disturbances were, however, noted to alleviate following the co-administration of melatonin (10 mg/kg b.w.). Overall, the present study is the first to provide evidence on the anti-inflammatory, anti-oxidant, anti-lipidic and, hence, therapeutic effects of melatonin with regard to the control and prevention of aluminium-intoxication.