Allergic inflammation is an immunological reaction to allergens that causes inflammation of tissues and dysfunction of organs. Symptoms of inflammation are redness, pain, heat and edema. Allergic inflammation involves T cells, eosinophils and mast cells. At the early stages of inflammation, histamine is released. After inflammation the cell produces prostaglandins, lymphocytes and monokines.
This study investigated the effects of extracts of the hulls of mangosteen (Garcinia mangostana), which has been used traditionally by the Thais as medicine to treat allergy. Previous studies have shown many promising properties of the mangosteen fruit: antioxidant action, anti-serotinin activity, inhibition of protein kinases, inhibition against HIV protease and antibacterial action against Staphylococcus aureus. The aim of this study was to determine the effect of extract from mangosteen hull on anti-inflammatory indicators such as histamine release and prostaglandin E2 production. This in-vitro study was carried out on rat leukaemia cells, which release histamine after contact with IgE. Mixtures of different ratios of water and ethanol were used as solvents to produce the extracts.
The researchers found that a 40 percent ethanol extract of mangosteen hull inhibited IgE-mediated histamine release of the leukaemia cells. The inhibition of this extract was higher than that of Rubus suavissimus, which is traditionally used as anti-allergy medicine in Japan. The other extracts only showed a tendency to inhibition. The extracts were also tested on their inhibitory effect on prostaglandin E2 release from rat glioma cells. The water extract had no effect on prostaglandin E2 release, whereas all the mangosteen hull extracts showed a dose-dependant inhibition. The main phytochemicals responsible for the inhibition are mangostins. The researchers also studied the effects of mangosteen extract on anaphylaxis in rats. The anaphylactic reaction was significantly reduced by the 40 percent ethanol extract.
The study concluded that the 40 percent ethanol extract of mangosteen hull inhibits histamine release and prostaglandin E2 synthesis. Mangosteen extract may be useful natural drug to treat allergy and inflammation.
Source: Nakatani K, Atsumi M, Arakawa T, Oosawa K, Shimura S, Nakahata N and Ohizumi Y. Inhibitions of histamine release and prostaglandin E2 synthesis by mangosteen, a Thai medicinal plant.
. Biological and Pharmaceutical Bulletin. 2002 September;25(9):1137-41