PhytoScience - Science 
Cardio protective - Invitro
Mangostin inhibits the oxidative modification of human low density lipoprotein. (LDL)
1: Free Radic Res. 1995 Aug;23(2):175-84. Related Articles, Links
Williams P, Ongsakul M, Proudfoot J, Croft K, Beilin L.
University of Western Australia, Department of Medicine, Royal Perth Hospital, Australia.
The oxidation of low density lipoprotein (LDL) may play an important role in atherosclerosis. We investigated the possible antioxidant effects of mangostin, isolated from Garcinia mangostana, on metal ion dependent (Cu2+) and independent (aqueous peroxyl radicals) oxidation of human LDL. Mangostin prolonged the lagtime to both metal ion dependent and independent oxidation of LDL in a dose dependent manner over 5 to 50 microM as monitored by the formation of conjugated dienes at 234 nm (P < 0.001).
There was no significant effect of mangostin on the rate at which conjugated dienes were formed in the uninhibited phase of oxidation.
Levels of thiobarbituric reactive substances (TBARS) generated in LDL were measured 4 and 24 hours after oxidation with 5 microM Cu2+ in the presence or absence of 50 microM or 100 microM mangostin.
We observed an inhibition of TBARS formation with 100 microM mangostin at 4 hours (P = 0.027) but not at 24 hours (P = 0.163). Similar results were observed in the presence of 50 microM mangostin. Mangostin, at 100 microM, retarded the relative electrophoretic mobility of LDL at both 4 and 24 hours after Cu2+ induced oxidation.
Mangostin (100 microM) significantly inhibited the consumption of alpha-tocopherol in the LDL during Cu2+ initiated oxidation over a 75 minute period (P < 0.001).
From these results, we conclude that mangostin is acting as a free radical scavenger to protect the LDL from oxidative damage in this in vitro system.
PMID: 7581813 [PubMed - indexed for MEDLINE]
Cardio protective - Invitro
Xanthone from Mangosteen inhibits oxidation of LDL cholesterol.
1: Free Radic Res. 2000 Nov;33(5):643-59. Related Articles, Links
Inhibition of lipoprotein oxidation by prenylated xanthones derived from mangostin.
Mahabusarakam W, Proudfoot J, Taylor W, Croft K.
Chemistry Department, Prince of Songkla University, Hat Yai, Thailand.
Oxidative damage is thought to play a critical role in cardiovascular and other chronic diseases. This has led to considerable interest in the antioxidant activity of dietary compounds.
Flavonoids have received the most attention and much is known about the structural requirements for antioxidant activity. However, little is known about the antioxidant activity of other plant derived phenolic compounds such as the xanthones.
We have previously shown that the prenylated xanthone, mangostin, can inhibit the oxidation of low density lipoprotein. In order to examine the effects of structure modification on antioxidant activity of this class of compound we have prepared a number of derivatives of mangostin and tested antioxidant activity in an isolated LDL and plasma assay.
The results of this study show that structural modification of mangostin can have a profound effect on antioxidant activity. Derivatisation of the C-3 and C-6 hydroxyl groups with either methyl, acetate, propane diol or nitrile substantially reduces antioxidant activity.
In contrast, derivatisation of C-3 and C-6 with aminoethyl derivatives enhanced antioxidant activity, which may be related to changes in solubility. Cyclisation of the prenyl chains had little influence on antioxidant activity.
PMID: 11200095 [PubMed - indexed for MEDLINE]
Cardio protective - Invivo
Cardioprotective effect of alpha-mangostin, a xanthone derivative from mangosteen on tissue defense system against isoproterenol-induced myocardial infarction in rats
Devi Sampath P, Vijayaraghavan K.
Centre for Advanced Studies in Botany, University of Madras, Guindy Campus, Chennai, India.
Increased oxidative stress and antioxidant deficit have been suggested to play a major role in isoproterenol-induced myocardial infarction
The present study was designed to evaluate the effect of alpha-mangostin on the antioxidant defense system and lipid peroxidation against isoproterenol-induced myocardial infarction in rats. Induction of rats with ISO (150 mg/kg body weight, ip) for 2 days resulted in a marked elevation in lipid peroxidation, serum marker enzymes (LDH, CPK, GOT, and GPT) and a significant decrease in the activities of endogenous antioxidants (SOD, CAT, GPx, GST, and GSH).
Pre-treatment with alpha-mangostin (200 mg/kg of body weight per day) orally for 6 days prior to the ISO administration and 2 days along with ISO administration significantly attenuated these changes when compared to the individual treatment groups.
These findings indicate the protective effect of alpha-mangostin on lipid peroxidation and antioxidant tissue defense system during ISO-induced myocardial infarction in rats.
PMID: 17994576 [PubMed - in process]
Cardio protective - Invivo
The mode of inhibitory action of alpha-mangostin, a novel inhibitor, on the sarcoplasmic reticulum Ca(2+)-pumping ATPase from rabbit skeletal muscle. (Protection from heart muscle failure)
Furukawa K, Shibusawa K, Chairungsrilerd N, Ohta T, Nozoe S, Ohizumi Y.
Department of Pharmaceutical Molecular Biology,
Faculty of Pharmaceutical Sciences,
Tohoku University, Sendai, Japan.
alpha-Mangostin, the principal ingredient of the fruit hull of Garcinia mangostana, caused a concentration-dependent decrease in the activities of both Ca(2+)-ATPase and Ca(2+)-transport of the sarcoplasmic reticulum from rabbit skeletal muscle with an IC50 value of 5 microM.
Neither Ca2+ release nor other enzyme activities were affected by alpha-mangostin.
Kinetic analysis of the inhibitory effects of alpha-mangostin on Ca(2+)-ATPase suggests that the inhibition of the ATPase is a noncompetitive-type with respect to ATP or Ca2+.
alpha-Mangostin may become a useful pharmacological tool for clarifying the physiological functions of Ca(2+)-pumping ATPase and sarcoplasmic reticulum.
PMID: 8886932 [PubMed - indexed for MEDLINE]