Effect of Guggulsterone and Cembranoids of Commiphora mukul on Pancreatic Phospholipase A(2): Role in Hypocholesterolemia

    Authors

    B. Z. Yu; R. Kaimal; S. Bai; K. A. El Sayed; S. A. Tatulian; R. J. Apitz; M. K. Jain; R. T. Deng;O. G. Berg

    Abstract

    Guggulsterone (7) and cembranoids (8-12) from Commiphora mukul stem bark resin guggul were shown to be specific modulators of two independent sites that are also modulated by bile salts (1-6) to control cholesterol absorption and catabolism. Guggulsterone (7) antagonized the chenodeoxycholic acid (3)-activated nuclear farnesoid X receptor (FXR), which regulates cholesterol metabolism in the liver. The cembranoids did not show a noticeable effect on FXR, but lowered the cholate (I)-activated rate of human pancreatic 113 phospholipase A2 (hPLA2), which controls gastrointestinal absorption of fat and cholesterol. Analysis of the data using a kinetic model has suggested an allosteric mechanism for the rate increase of hPLA2 by cholate and also for the rate-lowering effect by certain bile salts or cembranoids on the cholate-activated hPLA2 hydrolysis of phosphatidylcholine vesicles. The allosteric inhibition of PLA2 by certain bile salts and cembranoids showed some structural specificity. Biophysical studies also showed specific interaction of the bile salts with the interface-bound cholate-activated PLA2. Since cholesterol homeostasis in mammals is regulated by FXR in the liver for metabolism and by PLA2 in the intestine for absorption, modulation of PLA2 and FXR by bile acids and selected guggul components suggests novel possibilities for hypolipidemic and hypocholesterolemic therapies.

    Journal Title

    Journal of Natural Products

    Volume

    72

    Issue/Number

    1

    Publication Date

    1-1-2009

    Document Type

    Article

    First Page

    24

    Last Page

    28

    WOS Identifier

    WOS:000262761700006

    ISSN

    0163-3864

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