Y. Oi et al., ALLIIN AND VOLATILE SULFUR-CONTAINING-COMPOUNDS IN GARLIC ENHANCE THETHERMOGENESIS BY INCREASING NOREPINEPHRINE SECRETION IN RATS, Journal of nutritional biochemistry, 9(2), 1998, pp. 60-66
The effects of alliin and volatile sulfur-containing compounds in garl
ic on thermogenesis were investigated in rats. Rats were fed high-fat
diet with or without a ethanol extracted-garlic powder (EE-garlic) sup
plemented at 0.8% for 28 days. After feeding, mitochondrial protein co
ntent in interscapular brown adipose tissue (IBAT) and plasma norepine
phrine secretion were significantly greater in rats given EE-garlic as
compared with control rats. The effects of the administrations of EE-
garlic and alliin on norepinephrine secretions were evaluated in anest
hetized rats. The norepinephrine concentrations of arterial blood were
significantly increased by EE-garlic and alliin administration, and t
hese increases were dose dependent. The administration of allylsulfide
s having a different number of sulfur atoms (diallyldisulfide and dial
lyltrisulfide) also significantly increased the norepinephrine secreti
on. The effects of the administration of EE-garlic, alliin, and dially
ldisulfide on thermogenesis were examined by the direct measurement of
IBAT and rectal temperatures in anesthetized rats. The temperatures w
ere significantly increased by the administration of these compounds,
and the effect of diallyldisulfide disappeared in the presence of beta
-adrenergic blocker. These results suggest that the administration of
alliin and volatile sulfur-containing compounds in garlic enhance the
thermogenesis by increasing norepinephrine secretion via beta-adrenerg
ic action. (C) Elsevier Science Inc. 1998.