In the previous paper in this series, 2) we described the identification of trypanocidal xanthones in Garcinia subelliptica against epimastigotes and trypomastigotes of the protozoan Trypanosoma cruzi, which is the etiologic agent of Chagas' disease (American trypanosomiasis). In the course of our search for trypanocidal constituents in plants, we have found that the MeOH extract of the aerial parts of Physalis angulata L. (Solanaceae) showed considerable activity.P. angulata is indigenous to tropical America and was naturalized in Japan in the Edo era. It is an annual small herb and has been traditionally utilized for antipyretic purposes in Japan.3) The isolation of ergostane-type steroidal compounds, physagulins A-G, 4-6) withangulatin A 7) and physalins, 8) has been reported from this plant.T. cruzi is transformed into three stages in its life cycle: epimastigote in the insect gut; trypomastigote, an infectious form in the mammalian blood stream; and amastigote, a proliferative form in mammalian cells. During the isolation procedure, trypanocidal activity was monitored against epimastigotes, because it is easy to cultivate them and they are not infectious. Ten withanolides (1-10) were isolated from the active fraction. To check the therapeutic possibility of these withanolides, trypanocidal activity against trypomastigotes, an infectious form, was examined. Furthermore, evaluation of the IC 50 value against epimastigotes was performed using Cell Counting Kit-8 in order to compare with cytotoxicity at the IC 50 value. In this paper we describe the structural elucidation of the four new withanolides (2, 5, 9, 10) and the trypanocidal activity of the isolates. The possibility of chemotherapeutic utility is also discussed. MATERIALS AND METHODSPlant Materials P. angulata was cultivated in the medicinal plant garden of Fukuoka University and harvested in September 2002. The aerial parts were air-dried and powdered.Instruments and Reagents The instruments used in this study were a JEOL JNM-A500 for NMR spectra (500 MHz for 1 H-NMR, 125 MHz for 13 C-NMR), a JEOL JMS-HX 110 for MS spectra, a JASCO DIP 360 polarimeter for optical rotations, and a Labsystems Multiskan JX Microplate Reader for measuring the absorbance of a formazan product. The following materials were used for chromatography: Diaion HP-20 (a styrene polymer, Mitsubishi Chemical Industries, Ltd.), Silica gel 60N (Cica), Sephadex LH-20 (Pharmacia Fine Chemicals), and YMC gel (ODS, YMC Co. Ltd.). Newborn calf serum (NCS) was purchased from Nacalai Tesque. Dulbecco's modified Eagle's medium (DMEM) and RPMI 1640 medium were purchased from Sigma. Gentian violet, ketoconazole, and 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) were purchased from Wako. A Cell Counting Kit-8 was purchased from Dojindo. Other reagents are the same as in the previous papers. 2,9)Cultivation of T. cruzi The strain of T. cruzi used in this study and the cultivation methods of epimastigotes and trypomastigotes were the same as those described in the previous p...

Abstract. Gnathostomiasis was first described in Mexico in 1970, and endemic areas have been spreading in six states of this country. In Culiacan, Sinaloa, 300 cases of cutaneous larva migrans were recorded between January 1992 and December 1995. In addition, a Gnathostoma larva was surgically removed from the eye of one patient. Cutaneous lesions were observed mainly on the face, neck, arms, and legs. About 70% of the patients showed eosinophilia. A skin biopsy was carried out on 35 patients and the parasite was identified in histopathologic sections of 12 of these patients. In four patients, the larva migrated out spontaneously from the skin. An enzyme-linked immunosorbent assay using a crude somatic extract of adult Gnathostoma doloresi worms showed that 93% of the patients were seropositive, confirming the reliability of clinical diagnosis. A total of 14 advanced third-stage Gnathostoma larvae were found in four species of ichthyophagous birds captured on dams and dikes near the city of Culiacan. Scanning electron micrographs of human and bird larvae showed that they were morphologically indistinguishable from G. spinigerum. We conclude that the life cycle of Gnathostoma has been established in Sinaloa, and has become a serious public health issue for residents.Gnathostomiasis is one of the important food-borne parasitic zoonoses caused by infection with larvae of the spirurid nematode, genus Gnathostoma, with the disease being characterized principally as cutaneous larva migrans. 1 Among 12 distinctive species, only G. spinigerum had been considered as the causative species of human gnathostomiasis until the recent discovery of human cases infected with G. hispidum, G. doloresi, and G. nipponicum in Japan. [2][3][4][5][6][7][8] The life cycle of Gnathostoma is essentially identical within the genus, with only slight variations in the secondary, paratenic, and definitive hosts. Eggs are released from adult worms that live in the stomach or esophagus wall of the definitive hosts (cats, dogs, and other wild mammals). After being hatched from eggs in fresh water, the first-stage larvae are ingested by copepods where they molt twice to become the early third-stage larva (L 3 ). They then develop into the advanced L 3 in fish and amphibians, the second intermediate hosts. They are then disseminated into a wide range of paratenic hosts such as large carnivorous fishes, reptiles, and birds along the food chain.Infection in humans occurs when the second intermediate/ paratenic hosts contaminated with the L 3 are ingested. The disease is endemic mainly in Japan and Thailand, where people prefer to eat raw freshwater fish as a delicacy. 2, 3, 9 Sporadic cases have also been described in other Asian countries. 2,3,9 In America, native cases were first found in Mexico and later in Ecuador. 10,11 Subsequently, a large number of patients with cutaneous migratory swellings were identified in the states of Oaxaca and Veracruz in Mexico. 12 Endemic areas in Mexico have spread to the states of Guerrero, Nayarit, Tamaulipas, a...

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Crude extracts of Mexican medicinal plants were screened for trypanocidal activity against Trypanosoma cruzi, which is the etiological agent for Chagas' disease, one of the most serious protozoan diseases in Latin America. There were 43 kinds of methanolic and other organic extracts from 39 plants which were examined by the preliminary screening test to see immobilization of epimastigotes of T. cruzi in vitro. Eighteen of them showed activity at the concentration of 2 mg/ml after incubation for 2 h, while 13 showed activity at the concentration of 1 mg/ml after incubation for 48 h. Among them, the MeOH extract of roots of Aristolochia taliscana (Aristolochiaceae), locally known as "Guaco," immobilized all the epimastigotes even at lower concentration of 0.5 mg/ml (48 h). In order to identify principal compounds for this activity, the MeOH extract of Guaco was subjected to bioassay-guided fractionation. From the active fractions, four neolignans, eupomatenoid-7 (1), licarin A (2), eupomatenoid-1 (5) and licarin B (6), and two lignans, austrobailignan-7 (3) and fragransin E 1 (4) were isolated. Compounds 1-4 immobilized all the epimastigotes at the minimum concentration of 25-75 m mg/ml after incubation for 48 h, while compounds 5 and 6 were inactive. Corresponding concentration of gossypol, berberine chloride and harmine was 280 m mg/ml, 300 m mg/ml and Ͼ500 m mg/ml, respectively.