PT  - JOURNAL ARTICLE
AU  - Ro, Jai Youl
AU  - Lee, Byung Chul
AU  - Kim, Ji Young
AU  - Chung, Yean Jun
AU  - Chung, Myung Hee
AU  - Lee, Seung Kee
AU  - Jo, Tae Hyung
AU  - Kim, Kyung Hwan
AU  - Park, Young In
TI  - Inhibitory Mechanism of Aloe Single Component (Alprogen) on Mediator Release in Guinea Pig Lung Mast Cells Activated with Specific Antigen-Antibody Reactions
DP  - 2000 Jan 01
TA  - Journal of Pharmacology and Experimental Therapeutics
PG  - 114--121
VI  - 292
IP  - 1
4099  - http://jpet.aspetjournals.org/content/292/1/114.short
4100  - http://jpet.aspetjournals.org/content/292/1/114.full
SO  - J Pharmacol Exp Ther2000 Jan 01; 292
AB  - We previously reported that the glycoprotein extracted from aloe strongly inhibited the mediator releases caused by the activation of guinea pig lung mast cells. Therefore, this study aimed to purify a single component that has an antiallergic effect from crude aloe extract and then to assess the effects of aloe single component (alprogen) on the mechanism of mediator releases caused by the mast cell activation. We purified aloe extracts by using various columns. We also purified mast cells from guinea pig lung tissues by using enzyme digestion, rough and discontinuous density Percoll gradient. Mast cells were sensitized with IgG1(anti-ovalbumin) and challenged with ovalbumin. Histamine was assayed by using a fluorometric analyzer and leukotrienes by radioimmunoassay. [Ca2+]i level was analyzed by using a confocal laser scanning microscope. Protein kinase activity was determined by the protein phosphorylated with [γ-32P]ATP. The phospholipase D activity was assessed by the labeled phosphatidylalcohol. The amount of mass 1,2-diacylglycerol (DAG) was measured by the [3H]DAG produced when prelabeled with [3H]myristic acid. Phospholipase A2 activity was determined by measuring the lyso-phosphatidylcholine released from the labeled phospholipids. Alprogen significantly decreased histamine and leukotriene releases and blocked completely Ca2+ influx during mast cell activation. The protein kinase C and phospholipase D activities were decreased by alprogen in dose-dependent manner. Alprogen inhibited mass DAG formation and the phospholipase A2 activity during mast cell activation. The data suggest that alprogen purified from aloe inhibits multiple signals as well as blocking Ca2+ influx caused by mast cells activated with specific antigen-antibody reactions and that then the inhibition of histamine and leukotriene release follows. The American Society for Pharmacology and Experimental Therapeutics