Antioxidant and anti-atherogenic activities of three Piper species on atherogenic diet fed hamsters.
ABSTRACT Atherogenic diet is known to induce high plasma lipid concentration, oxidative stress and early atherosclerosis. Antioxidants have potentials to counter the effect of atherogenic diet. The present research aims at evaluating the antioxidant and anti-atherosclerotic activities of three Piper species (Piper guineense, Piper nigrum and Piper umbellatum) on atherogenic diet fed hamsters. Hamsters divided into 8 groups: normal control, atherosclerotic control and six test groups. The normal animals fed normal rodent chow, the atherosclerotic control animals fed the same rodent chow supplemented with 0.2% cholesterol and 10% coconut oil (high cholesterol diet). The 6 test groups' animals fed same diet as the atherosclerotic control group but with additional supplementation of 2 graded doses (1 and 0.25 mg/kg body weight, o.p.) of plant extracts for 12 weeks. The atherogenic diet induced a collapse of the erythrocyte antioxidant defense system (significant decrease in superoxide dismutase, catalase and glutathione peroxidase activities). Atherogenic diet also induced an increase in plasma total cholesterol, triglyceride, thiobarbituric acid reactive substances (TBARS), oxidation of low density lipoprotein cholesterol (LDL) and accumulation of foam cells in the aorta a hall mark for atherosclerosis. Administration of the Piper species prevented the collapse of the antioxidant system and the increase of plasma parameters maintaining them towards normality. The Piper species also prevented LDL oxidation by increasing the time (lag time) for its oxidation. The results suggest that these Piper species have significant antioxidant and anti-atherogenic effect against atherogenic diet intoxication.
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ABSTRACT: Pre-clinical and clinical studies points to the use of antioxidants as an effective measure to reduce the progression of oxidative stress related disorders. The present study evaluate the effect of three Piper species (Piper guineense, Piper nigrum and Piper umbellatum) for the protection of cardiac, hepatic and renal antioxidant status of atherogenic diet fed hamsters. Hamsters were classified into eight groups: a normal control, atherogenic control and six other experimental groups (fed atherogenic diet supplemented with different doses of P. nigrum, P. guineense and P. umbellatum (1 and 0.25 g/kg) for 12 weeks. At the end of the feeding period the heart, liver and kidney from each group were analyzed for lipid profile and antioxidant enzymes activities. Atherogenic diet induced a significant (P < 0.001) increase in the lipid profile across the board and equally significantly altered the antioxidant enzyme activities. Supplementation with Piper species significantly inhibited the alteration effect of atherogenic diet on the lipid profile and antioxidant enzymes activities. The Piper extracts may possess an antioxidant protective role against atherogenic diet induced oxidative stress in cardiac, hepatic and renal tissues.Food Chemistry 10/2012; 134(3):1354-1359. DOI:10.1016/j.foodchem.2012.03.030, · 3.26 Impact Factor
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ABSTRACT: Piper umbellatum L., Piperaceae, is a shrub that grows up to 3m high. It is commonly known as "capeba" or "pariparoba" in Brazil. Tea prepared using the leaves of this plant is employed in the treatment of infections and inflammatory processes in different countries. Approximately 50 compounds, notably from the flavonoid, alkaloid, terpene, and sterol classes, have been isolated from the leaves of Piper umbellatum. To evaluate the acute toxicity, antibacterial activity, and mode of action of the hydroethanolic extract of P. umbellatum leaves (HEPu). Acute toxicity of HEPu against CHO-K1 cells was evaluated using a cytotoxicity assay with Alamar Blue and that against mice was assessed by the Hippocratic test. Antibacterial activity of HEPu was tested using the broth microdilution method using a panel of clinically relevant bacteria, and the effects of HEPu on the bacterial membrane were analyzed in detail. A preliminary phytochemical analysis based on coloration/precipitation was performed according to procedure described in the literature. Secondary metabolites detected were analyzed and confirmed by thin layer chromatography (TLC), spectrophotometry, and high performance liquid chromatography (HPLC). P. umbellatum did not appear to be toxic in the in vitro (IC50 >200µg/mL) cytotoxicity test. When administered in vivo at doses up to 2000mg/kg p.o., HEPu did not cause any signs or symptoms of toxicity in mice. It demonstrated a good spectrum of antibacterial activity and its mode of action appeared to be associated with changes in the permeability of bacterial membranes; it led to increased entry of hydrophobic antibiotics, efflux of K(+), and nucleotide leakage. Preliminary phytochemical analysis revealed the presence of flavonoids, alkaloids, terpenes, and sterols in the extract. Spectrophotometric and HPLC analysis revealed the presence of the flavonoids rutin and quercetin. In summary, HEPu has antibacterial activity and low acute toxicity in vitro and in vivo. Its mode of action appears to be associated with changes in the permeability of the bacterial cell wall and cytoplasmic membrane, which can at least be partly attributed to the flavonoids present in the extract.Journal of ethnopharmacology 11/2013; 151(1). DOI:10.1016/j.jep.2013.10.011 · 2.94 Impact Factor
Article: Antioxidant activity of peppersEuropean Journal of Lipid Science and Technology 03/2014; 116(3). DOI:10.1002/ejlt.201400036 · 2.03 Impact Factor