Garlic platelet inhibition

Rahman, K. and Billington, D. 2000. Dietary supplementation with aged garlic extract inhibits ADP-induced platelet aggregation in humans. J. Nutr. 130, 2662-2665. 

Garlic has been shown to have significant effects on the cardiovascular system. Such areas include improvement in lipids, modest effects on blood pressure, platelet inhibition, antioxidant effects, and a decrease in fibrinolytic activity. In vitro studies have shown garlic possesses specific antiatherosclerotic effects such as reducing inducible nitric oxide synthase (iNOS) mRNA expression (10), inhibition of oxidized low-density lipoprotein (LDL)-induced lactate dehydrogenase (LDH) release and inhibition of oxidized LDL-induced depletion of glutathione (11). 

Rendu F, Daveloose D, Debouzy JC, BourdeauN, Levy-Toledano S, Jain MK, Apitz-Castro R. Ajoene, the antiplatelet compound derived from garlic, specifically inhibits platelet release reaction by affecting the plasma membrane internal microviscosity. U 150 INSERM, URA 184 CNRS, Hopital Lariboisiere, Paris, France. 

Aqueous extracts of raw garlic also inhibited cyclooxygenase activity in rabbit platelets, again contributing to an antithrombotic effect. In addition, AGE and S-allyl cysteine and S-allyl mercapto-cysteine have antiplatelet adhesion effects. Platelet adhesion to the endothelial surface is involved in atherosclerosis initiation. Furthermore, S-allyl mercaptocysteine inhibits the proliferation of rat aortal smooth muscle cells, another important... 

Garlic s proven mechanisms of action include (a) inhibition of platelet function, (b) increased levels of two antioxidant enzymes, catalase and glutathione peroxidase, and (c) inhibition of thiol enzymes such as coenzyme A and HMG coenzyme A reductase. Garlic s anti-hyperlipidemic effects are believed to be in part due to the HMG coenzyme A reductase inhibition since prescription medications for hyperlipidemia have that mechanism of action (statins). It is unknown whether garlic would have the same drug interactions, side effects, and need for precautions as the statins. 

Srivastava KC. (1984). Aqueous extracts of onion, garlic and ginger inhibit platelet aggregation and alter arachidonic acid metabolism. Biomed Biochim Acta. 43(8-9) S335-46. 

Garlic clearly has antithrombotic properties. Ajoene (an allicin metabolite) and methyl allyl trisulfide inhibit platelet aggregation. Garlic may promote vasodilation by relaxing smooth muscle, and it may reduce low-density lipoprotein (LDL) oxidation. 

Lawson LD, Ranson DK, Hughes BG. Inhibition of whole blood platelet-aggregation by compounds in garlic extracts and commercial garlic products. Thromb Res 1992 65 141-156. 

Garlic is used for a variety of reasons, and some of the attributes associated with it, e.g. for cancer prevention, or to reduce heart attacks, may not be substantiated. Other properties such as antimicrobial activity, effects on lipid metabolism, and platelet aggregation inhibitory action have been demonstrated. Ajoene has been shown to be a potent antithrombotic agent through inhibition of platelet aggregation. 

Garlic (Allium sativum) is thought to have several beneficial cardiovascular effects, such as lowering blood pressure and serum lipid, and antithrombotic activity. Garlic oil has been reported to interrupt thromboxane synthesis, thereby inhibiting platelet function. 

The exact mechanism by which garlic oil may suppress Fe-NTA-mediated renal damage is not known. However, onion and garlic extracts have been shown to inhibit platelet aggregation and prostaglandin synthesis. 

Antiplatelet effect (bilberry leaf, evening primrose, garlic, ginger, gingko biloba, ginseng). Clove contains eugenol derivatives, which inhibit platelets... 

The allyl sulfur compounds of garlic also have an anticoagulant action (by inhibiting platelet coagulability) and inhibit cholesterol synthesis by inactivating HMG-CoA reductase. 

Makheja AN, Vanderhoek JY, Bailey JM. Inhibition of platelet aggregation and thromboxane synthesis by onion and garlic. Lancet 1979 1 781. 

Other investigators have shown that oily garlic extracts, which contain ajoene, are able to inhibit enzymes necessary for arachidonic acid conversion to thromboxane (Srivastava anad Tyagi, 1993). Makheja et al. (1979) demonstrated the effect of garlic oil on platelet thromboxane synthesis. Human and rabbit platelets were incubated with garlic oil, resulting in almost complete... 

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