Oxidative stress is an important etiology of chronic diseases and many studies have shown that natural products might alleviate oxidative stress-induced pathogenesis. The study aims to evaluate the effect of Argan oil and Syzygium aromaticum essential oil on hydrogen peroxide (H2O2)-induced liver, brain and kidney tissue toxicity as well as biochemical changes in wistar rats. The antioxidant content of Argan oil and Syzygium aromaticum essential oil was studied with the use of gas chromatography. The animals received daily by gavage, for 21 days, either distilled water, Syzygium aromaticum essential oil, Argan oil, H2O2 alone, H2O2 and Syzygium aromaticum essential oil, or H2O2 and Argan oil. Blood samples were withdrawn on day 21 for the biochemical blood tests, and the kidney, liver and brain tissue samples were prepared for histopathology examination. The results showed that the content of antioxidant compounds in Syzygium aromaticum essential oil is higher than that found in Argan oil. H2O2 increased level of blood urea, liver enzymes, total cholesterol, Low Density Lipoprotein (LDL-C), Triglycerides (TG) and Very Low Density Lipoprotein (VLDL), and decreased the total protein, albumin and High Density Lipoprotein-cholesterol (HDL-C). There was no significant effect on blood electrolyte or serum creatinine. The histopathology examination demonstrated that H2O2 induces dilatation in the central vein, inflammation and binucleation in the liver, congestion and hemorrhage in the brain, and congestion in the kidney. The H2O2-induced histopathological and biochemical changes have been significantly alleviated by Syzygium aromaticum essential oil or Argan oil. It is concluded that the Argan oil and especially the mixture of Argan oil with Syzygium aromaticum essential oil can reduce the oxidative damage caused by H2O2, and this will pave the way to investigate the protective effects of these natural substances in the diseases attributed to the high oxidative stress.

The present study was designed to investigate the preventive effect of propolis, bee pollen and their combination on Type 2 diabetes induced by D-glucose in rats. The study was carried out by feeding daily two concentrations (100 and 200 mg/Kg BW) of propolis or bee pollen (or their combination to normal (non-diabetic) and diabetic rats for a period of 16 weeks. In vivo biochemical changes associated to diabetes are induced by drinking a solution containing 10% of D-glucose (diabetic rats). The in vitro antioxidant activity was also evaluated and the chemical composition of propolis and bee pollen extracts was determined by UHPLC-DAD. Phytochemical composition of propolis and bee pollen revealed the presence of several natural antioxidants, such as hydroxycinnamic acids, hydroxybenzoic acids, flavonoids, flavan-3-ols and stilbens. The major antioxidant compound present in propolis was Naringin (290.19 ± 0.2 mg/Kg) and in bee pollen was apigenin (162.85 ± 17.7 mg/Kg). These results have been related with a high antioxidant activity, more intense in propolis extract. In rats, the administration of D-glucose had induced hyperglycemia (13.2 ± 0.82 mmol/L), increased plasmatic insulin levels (25.10 ± 2.12 U/L) and HOMA-IR index (14.72 ± 0.85) accompanied with dyslipidemia, elevation of hepatic enzyme levels, and a change in both serum renal biomarkers and plasmatic calcium. The coadministration of propolis and bee pollen extracts alone or in combination restored these biochemical parameters and attenuated the deleterious effects of D-glucose on liver and kidney functions. Furthermore, these effects were better attenuated in the combined therapy-prevented diabetic rats. Hence, it is possible to conclude that propolis and bee pollen can be used as a preventive natural product against diabetes induced dyslipidemia and hepato-renal damage.

The main objective of this study is to determine the effects of apple vinegar on the metabolic changes caused by hypercaloric diet in Wistar rats. Apple vinegar was first analyzed to find out the total acidity, the polyphenolic and flavonoid contents, the total antioxidant capacity, and the free radical scavenging activity. In vivo study on adult male and female Wistar rats was conducted by administering a drink containing either 10% D-glucose or water (control) for five weeks. Apple vinegar is administered daily by gavage (2 mL/kg) to rats fed D-glucose for 5 weeks. The results showed that the polyphenolic content in apple vinegar was 148.02±10.16 mg GAE/100 mL, flavonoid content was 22.93±0.73 QE/100 mL, and total antioxidant capacity was 13.4±0.47 mg AAE/100 mL. Free radical IC50 apple vinegar scavenging activity (DPPH) was 0.74±0.154 μL/mL. The total acidity was (3.24±0.02 mg AAE/100 mL). The treatment during five weeks with D-glucose leads to increased plasma glucose, lipid profile, hepatic enzyme levels, urea, and creatinine. Simultaneous treatment with apple vinegar improves the parameters studied. These results clearly show that the daily consumption of vinegar can reduce the rise in blood sugar and lipid profile induced by hypercaloric diet in rats. Therefore, the use of apple vinegar would have a very beneficial effect in the prevention of metabolic disorders caused by high-caloric food.

Bee products are a promising source of phenolic compounds with strong antioxidant activity. The present study was designed to explore the protective effect of honey, propolis, and their combination on gentamicin-induced oxidative stress and hepatorenal dysfunction. This study was conducted on male Wistar rats by intraperitoneal injections of gentamicin (120 mg/kg BW/day, i.p.) or normal saline (1 ml/kg BW/day, i.p.) for 10 consecutive days. Honey (2 g/kg BW), propolis (100 mg/kg BW), or their combination were given daily by gavage to normal and gentamicin groups. Honey and propolis samples were evaluated for their phytochemical composition and antioxidant capacity. The in vitro investigations showed that the evaluated samples especially propolis extract have high antioxidant power associated with the presence of several phenolic compounds such as flavonoids, flavan-3-ols, hydroxybenzoic acids, hydroxycinnamic acids, and stilbenes, while honey contains only hydroxybenzoic acids and hydroxycinnamic acids. It was also shown that simultaneous treatment with honey or propolis extract alone or in association prevented changes caused by gentamicin administration and improved hepatic and renal functions. Changes caused by gentamicin administration, observed by in vivo experiments, include significant elevation of uric acid, urea, creatinine, and hepatic enzyme levels (ALT, AST, and ALP) and kidney biochemical changes (an increase of urea, uric acid, and creatinine and a decrease of albumin and total protein) as well as remarkable changes of renal and liver oxidative stress markers (CAT, GPx, and GSH) and elevation of MDA levels. Overall, it can be concluded that honey and propolis might be useful in the management of liver and renal diseases induced by xenobiotics.

Aim: The study investigated the chemical composition, antioxidant content, and antioxidant activity of Thymus vulgaris honey (TVH) and Origanum vulgare essential oil (OVEO) and their mixture effect on carbon tetrachloride (CCl4)-induced toxicity. Materials and Methods: The study conducted physicochemical characterization and chemical analysis of TVH and OVEO with the use of gas chromatography–mass spectrometry and high-performance liquid chromatograph (HPLC). The antioxidant activity of TVH and OVEO was done with the use of 1,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. The study used nine groups of rats to investigate the effect of TVH, OVEO, and a mixture of TVH and OVEO (HEM) on CCl4-induced toxicity. Intraperitoneal injection of CCl4 (1 mL/100 g) was used to induce toxicity. The doses of TVH and OVEO were 1 mg/kg.b.wt, and 50 mg/kg.b.wt, respectively. HEM contains TVH (1 mg/kg.b.wt) and OVEO (50 mg/kg.b.wt). Results: TVH has a high content of phenols, flavonoids, and flavanols. HPLC analysis showed that TVH contains, for the 1st time, epicatechin gallate, and at a high concentration. OVEO includes a high percentage of carvacrol and thymol. With the use of DPPH, OVEO was more potent than TVH. CCl4 caused significant liver and kidney damage and lipid disorders, which were alleviated by HVT, OVEO, and HEM. HVT was more potent than OVEO (p<0.05), and HEM was more potent than HVT and OVEO (p<0.05). Conclusion: The study identified high content of epicatechin gallate for the 1st time in TVH, and OVEO contains a high percentage of thymol and carvacrol. Epicatechin gallate might be useful as a marker for TVH. Mixing OVEO and TVH significantly potentiated their protection against CCl4-induced liver and kidney toxicity.