garlic
Effects of garlic powders with varying alliin contents on hepatic drug metabolizing enzymes in rats.

Le Bon AM, Vernevaut MF, Guenot L, Kahane R, Auger J, Arnault I, Haffner T, Siess MH.

Unite Mixte de Recherche de Toxicologie Alimentaire, Institut National de la Recherche Agronomique, 17 rue Sully, 21065 Dijon Cedex, France. lebon dijon.inra.fr

The anticarcinogenic effect of garlic has been demonstrated in both epidemiologic and experimental studies. In this study, possible mechanisms involved in the anticarcinogenic effect of garlic consumption were assessed by determining its capacity to alter drug metabolizing enzymes, in relation with its alliin content. Rats were fed a diet for 2 weeks containing 5% garlic powders produced from bulbs grown on soils with different levels of sulfate fertilization and therefore containing differing amounts of alliin. Activities of several hepatic enzymes, which are important in carcinogen metabolism such cytochromes P450 (CYP) and phase II enzymes, were determined. Garlic consumption slightly increased ethoxyresorufin O-deethylase and CYP 1A2 levels. In contrast, garlic consumption decreased CYP 2E1 activity and the level of the corresponding isoform. UDP glucuronosyl transferase and glutathion S-transferase activities were increased by garlic powders. The alliin content of the garlic powders was positively correlated with UGT activity although not with other activities. Effects produced by garlic consumption were qualitatively similar to that of diallyl disulfide, a sulfur compound that has been extensively studied. These data could partially explain the chemoprotective effect of garlic.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=14664517&dopt=Abstract garlic



garlic
Garlic (Allium sativum) as an anti-Candida agent: a comparison of the efficacy of fresh garlic and freeze-dried extracts.

Lemar KM, Turner MP, Lloyd D.

Microbiology (BIOSI 1), Cardiff University, Cardiff, Wales, UK. Lemarkm cf.ac.uk

AIMS: To determine the effects of fresh and freeze-dried extracts of Allium sativum on the physiology and morphology of Candida albicans. METHODS AND RESULTS: Inhibition of growth in glucose-yeast extract-peptone was measured using a multiwell plate reader. Scanning and transmission electron microscopy investigations indicated loss of structural integrity. Gas chromatography-mass spectrometry of extracts was employed to separate and quantify putative inhibitory sulphur-containing components. CONCLUSIONS: Fresh garlic extract has a greater efficacy than garlic powder extract as indicated both by its effects on morphology and inhibition of growth. SIGNIFICANCE AND IMPACT OF THE STUDY: The ubiquitous opportunistic pathogen C. albicans is sensitive to garlic; resistance to the broad spectrum of active principles present is unlikely so that its anticandidal effects may provide an important alternative route to chemotherapy.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12174037&dopt=Abstract garlic



garlic
Protection against acute adriamycin-induced cardiotoxicity by garlic: role of endogenous antioxidants and inhibition of TNF-alpha expression.

Mukherjee S, Banerjee SK, Maulik M, Dinda AK, Talwar KK, Maulik SK.

Department of Pharmacology, All India Institute of Medical sciences, New Delhi-110029 India. ansam77 rediffmail.com

BACKGROUND: Oxidative stress is the major etiopathological factor in adriamycin-induced cardiotoxicity. Relatively low amounts of endogenous antioxidant makes the heart vulnerable to oxidative stress-induced damage. Chronic oral administration of garlic has been reported to enhance the endogenous antioxidants of heart. We hypothesized that garlic-induced enhanced cardiac antioxidants may offer protection against acute adriamycin-induced cardiotoxicity. RESULTS: Rats were either administered freshly prepared garlic homogenate (250 and 500 mg/kg daily, orally, for 30 days) or probucol (cumulative dose, 120 mg/kg body weight divided in 12, i.p. over a period of 30 days) or double distilled water (vehicle), followed by a single dose of adriamycin (30 mg/kg i.p.). In the adriamycin group, increased oxidative stress was evidenced by a significant increase in myocardial TBARS (thiobarbituric acid reactive substances) and decrease in myocardial SOD (superoxide dismutase), catalase and GPx (glutathione peroxidase) activity. Histopathological studies showed focal as well as subendocardial myocytolysis with infiltration of macrophages, lymphocytes and edema. Immunocytochemistry showed marked expression of TNF-alpha (tumor necrosis factor-alpha) in the myocardium. Increase in myocardial TBARS and decrease in endogenous antioxidants by adriamycin was prevented significantly in the garlic treated rat hearts, which was comparable to the probucol-treated group. Histopathological evidence of protection was also evident in both garlic-treated and probucol-treated groups. Probucol, 250 mg/kg and 500 mg/kg of garlic reduced adriamycin induced TNF-alpha expression in the myocardium and was associated with reduced myocyte injury. CONCLUSIONS: It is concluded that chronic garlic administration prevents acute adriamycin-induced cardiotoxicity and decreases myocardial TNF-alpha expression.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=14687418&dopt=Abstract garlic



garlic
Endothelium mediated vasorelaxant response of garlic in isolated rat aorta: role of nitric oxide.

Ashraf MZ, Hussain ME, Fahim M.

Department of Physiology, Vallabhbhai Patel Chest Institute, University of Delhi, PO Box 2101, Delhi 110007, India.

The vasorelaxant effect of garlic (Alium sativum L.) has been suggested to be partially mediated through endothelium. The present study was designed to evaluate the role of various endothelium-mediated mechanisms in vasorelaxant response of garlic on isolated aortic rings of rats. In tissues precontracted with phenylephrine (PE) 10(-6)M, concentration-response curve for different concentrations of garlic (1, 5, 10, 20 and 50 microg/ml) was examined. In all the preparations garlic showed a concentration-dependent vasorelaxant response. There was a significant attenuation of vasorelaxation in tissues pretreated with K(+) channel blocker, glybenclamide (10(-6)M). Indomethacin (10(-5)M) enhanced the relaxant response of garlic. N(G)-Monomethyl-L-arginine (L-NMMA) 30 microM, a potent inhibitor of nitric oxide synthase, did not produce any significant effect on the response of garlic. However, cGMP blocker methylene blue (10(-5)M) showed a strong vasoconstriction and inhibited the vasorelaxant response of garlic. The results indicate that endothelium modulated vasorelaxation of garlic is partly mediated through EDHFs and cycloxygenase pathways. However, relaxing factor(s) other than NO, mediated through cGMP has a major role in the vasorelaxant response of garlic.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=14698500&dopt=Abstract garlic



garlic
Inhibitory effect of whole strawberries, garlic juice or kale juice on endogenous formation of N-nitrosodimethylamine in humans.

Chung MJ, Lee SH, Sung NJ.

Department of Food and Nutrition, Gyeongsang National University, Jinju 660-701, South Korea.

In vitro and in vivo experiments were performed on inhibition of nitrosation by strawberry, garlic, and kale extracts. Strawberry, garlic, and kale extracts inhibited nitrosation in vitro. However, garlic extract has a greater ability to inhibit the chemical nitrosation in vitro than strawberry and kale extracts. The garlic methanol-soluble fraction of the garlic extract was fractionated into G1-G4 fractions by Prep-LC. Fraction G1 inhibited N-nitrosodimethylamine (NDMA) formation by 84+/-1%. We studied the formation of the carcinogen NDMA in humans after administration of nitrate (400 mg/day) in combination with an amine-rich diet and its possible inhibition by administration of whole strawberries (300 g), garlic juice (200 g: 75 g garlic juice in drinking water), or kale juice (200 g) in 27 males and 13 females (ten healthy volunteers in each group) of age 24+/-3 years. Nitrate intake resulted in a significant rise in mean salivary nitrate and nitrite concentrations. Also, nitrate excretion in urine during the experimental day was significantly increased compared with the control days. When whole strawberries, garlic juice, or kale juice was provided immediately after an amine-rich diet with a nitrate, NDMA excretion was decreased by 70, 71, and 44%, respectively, compared with NDMA excretion after ingestion of an amine-rich diet with a nitrate. These results suggest that consumption of whole strawberries, garlic juice, or kale juice can reduce endogenous NDMA formation.

Online source: www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=12175517&dopt=Abstract garlic