Phytochemical and anti-inflammatory properties of Senegalese propolis and isolated compounds.

Propolis is a chemically complex resinous product collected from various plant sources by honeybees that has been used historically a traditional folk medicine in many parts of the world. The main constituents of propolis are beeswax and plant resins. We recently obtained Senegalese propolis, which, to our knowledge, has not been previously reported. The purpose of this study was to analyze the composition of Senegalese propolis and evaluate its anti-inflammatory activity. Ten known phenolic compounds with phenanthrene or stilbene skeletons were isolated. Nitric oxide (NO) production assay revealed that Senegalese propolis suppresses lipopolysaccharide (LPS)-stimulated production of NO in J774.1 cells in a dose-dependent manner. The anti-inflammatory potency of Senegalese propolis was higher than that of other previously reported propolis. Furthermore, the eight compounds isolated from Senegalese propolis showed high anti-inflammatory activity by inhibiting the LPS-induced expression of inducible NO synthase (iNOS). These results suggest that Senegalese propolis and its components have potential applications as anti-inflammatory agents.

Chiisanoside is not absorbed but inhibits oil absorption in the small intestine of rodents.

Chiisanoside is the main component of Acanthopanax sessiliflorus leaves. Simultaneous administration of chiisanoside resulted in a decrease in the plasma TG level and increase of undigested TG in the intestinal lumen after oil gavage to mice. This suggests that chiisanoside has the potential to prevent obesity as a lipase inhibitor which suppresses fat absorption in vivo.

Lupane-type saponins from leaves of Acanthopanax sessiliflorus and their inhibitory activity on pancreatic lipase.

Three known saponins, chiisanoside, 11-deoxyisochiisanoside, and isochiisanoside, and one novel saponin, 3,4-seco-4(23),20(29)-lupadiene-3,28-dioic acid 28-O-alpha-l-rhamnopyranosyl (1-->4)-beta-d-glucopyranosyl (1-->6)-beta-d-glucopyranoside, referred to as sessiloside, were isolated from a hot water extract of Acanthopanax sessiliflorus leaves. All of these saponins were lupane-type triterpene triglycosides, and their concentrations were 4.1, 1.0, 0.5, and 0.4% (w/w) of the total extract, respectively. Sessiloside and chiisanoside inhibited pancreatic lipase activity in vitro, and addition of the saponin-rich fraction to a high-fat diet suppressed the body weight gain of mice. The possibility of application of the lupane-type saponins from A. sessiliflorus leaves to the treatment of obesity is discussed.

[Xanthine oxidase inhibitory activity and hypouricemia effect of propolis in rats].

The xanthine oxidase (XOD) inhibitory activity of propolis from China and Brazil was measured. The propolis from both place were seen to have XOD inhibitory activity. However, a stronger tendency was shown in the propolis from China. The compounds in each the propolis were measured quantitatively. A great deal of chrysin, galangin, and caffeic acid phenetyl ester were found in the propolis from China, an abundance of p-coumaric acid and artepillin C in the propolis from Brazil. Therefore it was revealed that the propolis compounds are very different depending on their place of origin. The XOD inhibitory activity of these five compounds was measured. Caffeic acid phenetyl ester had the strongest activity, with chrysin and galangin next; p-coumaric acid and artepillin C showed weak XOD inhibitory activity. We evaluated the hypouricemic effect of propolis from China on hyperuricemia induced by the uricase inhibitor, oxonic acid (500 mg/kg p.o., 1 h before the test drugs), and measured plasma uric acid values in rats. Oral propolis had a hypouricemic effect 2 h after its administration to oxonate-pretreated rats. These results suggested that a continuous intake of propolis may be effective for the prevention and the treatment of gout and hyperuricemia.

Absorption and urinary excretion of quercetin, rutin, and alphaG-rutin, a water soluble flavonoid, in rats.

Quercetin, rutin, alphaG-rutin (a water soluble flavonoid), and a mixture of rutin and alphaG-rutin were administered to rats by a single gastric intubation, and their absorption and urinary excretion were examined. The plasma and 24 h urinary levels of aglycons (quercetin and tamarixetin/isorhamnetin) were measured by HPLC after deconjugation with beta-glucuronidase/sulfatase treatment. alphaG-rutin was absorbed more rapidly than quercetin or rutin, and the plasma concentrations of quercetin and tamarixetin/isorhamnetin reached the highest peak level 30 min after dosing. Quercetin, rutin, and the mixture of rutin and alphaG-rutin showed the first peak level 8 h, 8 h, and 30 min after dosing, respectively. The area under the concentration-time curve (AUC) for quercetin in rats administered alphaG-rutin was approximately 4.5- and 2-fold higher than those in rats administered quercetin and rutin, respectively, and was almost the same as that in rats administered a mixture of rutin and alphaG-rutin. The highest 24 h urinary excretion was observed in alphaG-rutin-administered rats. These results suggest that alphaG-rutin is absorbed more efficiently than either quercetin or rutin and that a high plasma concentration can be maintained by supplying rutin and alphaG-rutin in combination.