Small daily doses of allicin, the active metabolic in garlic, proved effective in preventing a severe form of pulmonary hypertension in rats, according to a study reported Saturday, April 2 by <<>> researchers at the Experimental Biology 2005 meeting in San Diego. The human form of the disease – primary pulmonary hypertension – often leads to cardiovascular complications such as right heart hypertrophy and failure and is frequently lethal.
Dr. David D. Ku says the findings confirm an earlier study by the team that garlic protects against a less lethal form of acute pulmonary hypertension in rats. The new study by Ku, graduate student Hsien Chin Wu and research assistant Xiaowei Sun, not only looks at a chronic form of the disease but also goes a big step further by pinpointing the effective ingredient in garlic and demonstrating that it achieves its protective effects through vasorelaxation.
The presentation at Experimental Biology 2005 was part of the scientific sessions of the metabolite.
In the UAB study, rats were given a single dose of monocrotaline, a well-established mechanism for inducing vasoconstriction of the pulmonary arteries. Within three weeks, half the rats had developed chronic pulmonary hypertension, with markedly increased pulmonary arterial pressure, just as expected. But the other half experienced no such increase. These rats had received the hypertension-causing drug but their diets also had been supplemented daily for three weeks with small doses of allicin. And it was the allicin, not the garlic itself that protected the supplemented rats from developing the disease, emphasizes Dr. Ku. Animals that consumed garlic from which the active metabolite had been removed or inactivated with heat experienced no benefit.
In a separate but related study also presented at Experimental Biology 2005, in the scientific sessions of the American Society for Pharmacology and Experimental Therapeutics, Dr. Ku's team found that garlic treatment also could protect coronary vascular function and lessen the severity of right heart hypertrophy, two of the serious byproducts of chronic pulmonary hypertension.