Hericium erinaceus is typically used in traditional Chinese medicine for mucosal protection, healing of gastric ulcers, and treatment of gastritis. We purified from the cultured mycelia of H. erinaceus a polysaccharide with anti-gastric ulcer and antigastritis activity, but its effects on gastric malignancy have not been elucidated. We examined the differential effects of this purified polysaccharide, named EP-1, on the human gastric (GES-1) cell line and a precancerous cell line (MC) that was transformed from GES-1 using N-methyl-N'-nitro-N-nitrosoguanidine. We observed that the polysaccharide potently induced cell apoptosis and cell cycle arrest at the G0/G1 phase in the MC cell line but did not have any effect on the GES-1 cell line at the same doses. Further mechanistic studies revealed that the polysaccharide exerted its activity through an apoptosis-associated pathway by modulating the expression of Bax, Bcl-2, and caspase-3. Differential effects of the polysaccharide on the GES-1 and MC cell lines indicate that the polysaccharide was effective in preventing gastric cancer progression.

BACKGROUND/AIMS: To test the impact of vitamin C supplementation on triple therapy for H. pylori eradication. METHODOLOGY: A total of 171 H. pylori-infected patients were randomized to receive different one-week triple therapies, including 20 mg omeprazole, 1 g amoxicillin, plus the following twice daily: (1) 250 mg clarithromycin (C250 group, n=55); (2) 250 mg clarithromycin and 500 mg vitamin C (V-C250 group, n=61); (3) 500 mg clarithromycin (C500 group, n=55). Six weeks after treatment, the success of H. pylori eradication was assessed by a 13C-urea breath test. Each collected H. pylori strain was defined as either clarithromycin susceptible or resistant by E-test. RESULTS: The demographic background, clarithromycin susceptibility of H. pylori, and drug compliance were similar among the three groups (p=NS). For clarithromycin susceptible infection, the V-C250 group had a higher eradication rate than the C250 group (ITT: 85% vs. 68% and PP: 90% vs. 73%, p = 0.03), but had an equivalent rate to the C500 group (p=NS). For clarithromycin resistant infection, all three groups had a similarly poor eradication rate of less than 34%. CONCLUSIONS: Adding vitamin C to one-week triple therapy can reduce the dosage of clarithromycin, but preserve the high eradication efficacy for clarithromycin susceptible H. pylori infection.

ETHNOPHARMACOLOGICAL RELEVANCE:The fungus Hericium erinaceus (Bull.) Pers is used in Chinese traditional medicine to treat symptoms related to gastric ulcers. Different extracts from the fungus were assessed for anti-Helicobacter pylori activity to investigate the antibacterial activity of the ethanol extracts from H. erinaceus and verify the traditional indication of use.

MATERIALS AND METHODS:The fruiting bodies of H. erinaceus were concentrated with ethanol by HPD-100 macroporous resin and the whole extract was partitioned by petroleum ether and chloroform to afford fractions with using a silica gel column. Several pure compounds of petroleum ether extracts were obtained and analyzed using nuclear magnetic resonance (NMR). The activity of the extracts and fractions towards H. pylori was assessed by the microdilution assay and by the disk diffusion assay in vitro. From the most active fraction, two pure compounds were isolated and identified as the main components with anti-H. pylori activity from the fungus H. erinaceus. The cytotoxicity of these two compounds against the human erythroleu-kemia cell line K562 was also evaluated.

RESULTS:The crude ethanol extracts from the fungus H. erinaceus were inhibitory to H. pylori. The petroleum ether extracts (PE1s, PE2s) and the chloroform extracts (TEs) demonstrated strong inhibition to H. pylori. The inhibition of H. pylori was observed through an agar dilution test with minimal inhibition concentration (MIC) values from 400μg/mL to 12.5µg/mL. Two pure compounds, 1-(5-chloro-2-hydroxyphenyl)-3-methyl-1-butanone and 2,5-bis(methoxycarbonyl)terephthalic acid were isolated from the petroleum ether fractions and identified using (1)H NMR and (13)C NMR spectra analysis. The MIC value for 1-(5-chloro-2-hydroxyphenyl)-3-methyl-1-butanone was 12.5-50µg/mL and the MIC value for 2,5-bis(methoxycarbonyl)terephthalic acid was 6.25-25µg/mL. Both two compounds showed weak cytotoxicity against K562 with IC50<200mM.

CONCLUSIONS:This study revealed that the extracts from petroleum ether contribute to the anti-H. pylori activity. The compounds obtained from petroleum ether extracts, 1-(5-chloro-2-hydroxyphenyl)-3-methyl-1-butanone and 2,5-bis(methoxycarbonyl)terephthalic acid, inhibit the growth of H. pylori.

Astaxanthin (Asx), one of the carotenoids, is a red pigment in fish and Crustaceans, and possesses stronger reduction properties than conventional carotenoids, like beta-carotene. However, little is known about the biochemical properties and physiological functions of astaxanthin. The effects of astaxanthin and vitamin C on stressed rats were studied physiologically and biochemically. beta-Carotene and three kinds of astaxanthins, which were extracted from Haematococcus and Phaffia, and synthesized chemically, were used in these experiments. These rats given astaxanthins or beta-carotene had stress induced on the 12th day by immersing the rats in chest-level water at 20 degrees C for 24 h after fasting for 24 h. Rats given astaxanthins or beta-carotene prior to stressing were appreciably protected against the evolution of gastric ulcerations in relation to control rats. Ulcer indexes in particular were smaller with the rat group fed astaxanthin extracted from Haematococcus than the other groups. Next, the effects of Asx and/or vitamin C on the protection of evolution of gastric ulcer in stressed rats were persued by the same methods as described above. The results showed that rats given Asx or vitamin C were appreciably protected against the evolution of gastric ulcerations in relation to control rats. The effects were more intense, especially in rats simultaneously supplied Asx and vitamin C than in rats taking either Asx or vitamin C. It was suggested that the simultaneous supplementation of food substances with astaxanthin and vitamin C would supply enough antioxidants to offset stress-related injuries.

Turnera ulmifolia is a plant belonging to the family Turneraceae, popularly known in Brazil as chanana. This species is distributed from Guyana to southern Brazil where it is considered a weed. The plant occurs in tropical rain forest, fields, and gardens. Chanana tea is used in Brazilian folk medicine for the treatment of diseases related mainly to gastric dysfunction including gastric and duodenal ulcers. In this study, the ability of a lyophilized infusion, as an aqueous fraction (AqF) of the aerial parts of T. ulmifolia, was investigated for its ability to prevent ulceration of the gastric and duodenal mucosa was examined in mice and rats, respectively. The AqF significantly reduced the formation of lesions associated with HCl/ethanol administration by 39% and 46%, respectively, at doses of 500 mg/kg and 1000 mg/kg, p.o. The AqF also significantly reduced the incidence of gastric lesions induced by a combination of indomethacin and bethanechol by 58% and 72% at doses of 500 mg/kg and 1000 mg/kg, respectively. In stress-induced gastric ulcer, the inhibition by the AqF was 48%, 57%, and 58% at doses of 250 mg/kg, 500 mg/kg, and 1000 mg/kg, respectively (p<0.05). A pyloric ligature experiment showed that the highest dose of the AqF significantly affected the gastric juice parameters by increasing the pH from 2.5 (control) to 5.3 and decreasing the acid output from 11.3 (control) to 3.7 mEq/ml/4 h. The AqF had no significant effect on duodenal ulcers induced by cysteamine. Preliminary phytochemical screening confirmed that flavonoids were the major constituents of the AqF of T. ulmifolia. These results indicate that this extract has a significant antiulcerogenic effect, as popularly believed.