Culture-Bound Syndromes of a Brazilian Amazon Riverine population: Tentative correspondence between traditional and conventional medicine terms and possible ethnopharmacological implications.

ETHNOPHARMACOLOGICAL RELEVANCE: It is not always possible to correlate the "emic" terms to the "etic" ones during ethnopharmacological surveys, especially regarding those related to Culture-Bound Syndromes (CBS). Nevertheless, it is the role of ethnopharmacology to address these correlations, since they are the basis for the understanding of potential bioactives. AIM AND OBJECTIVES: This study reports the clinical manifestations and therapeutic resources used for the treatment of CBS among some riverine inhabitants of Brazilian Amazonia. An effort was made to establish a correspondence between the local "emic" terms of traditional medicine and the symptoms or diseases known by conventional medicine ("etic" terms). The ultimate goal was to gain insights to suggest further pharmacological studies with the local resources. MATERIAL AND METHODS: Fieldwork was guided by methods of anthropology, botany and zoology-with the assistance of a doctor-among the traditional healing experts in Jaú National Park (during 199 days in 1995) and Unini River Extractive Reserve (210 days from 2008 to 2012). RESULTS: Fifty-nine healers of different kinds were interviewed: a prayer-maker, medium, natural resource expert, massage therapist, midwife and snakebite healer. The clinical manifestations and healing resources of the following CBS were collected: "mau olhado" (evil eye), "quebrante" (chipping); "espante" (fright or susto); "doença do ar" (air diseases); "vento caído" (fallen wind); "derrame" (leakage); "mãe do corpo" (mother of the body) and "panema" (unlucky). The first three seem to be local variations of other CBSs already described in Latin America. "doença do ar", "vento caído", "derrame" and "mãe do corpo" seem to be folk terms for known conventional medical disorders, while "panema" is a yet undescribed Brazilian CBS that is possibly related to dysthymic disorder or depression and deserves further investigation. Treatments included prayer rituals, fumigation, baths and oral remedies using 25 plants and 10 animals. CONCLUSION: It was possible to establish hypothetical correlations between CBS as described by the riverine population studied and some "etic" terms. The main importance of this is to help the proposition of target-oriented pharmacological studies of the natural resources used by these communities. Accordingly, the following plants are suggested to be submitted to further studies for antidepressant and anxiolytic activities: Siparuna guianensis, Mansoa alliacea, Leucas martinicensis, Petiveria alliacea, Annona montana and Alpinia nutans; for anti-seizure activity: Protium amazonicum, Protium aracouchini and Protium heptaphyllum; finally for antispasmodic activity: Leucas martinicensis.

The mystery of the 'resin-of-canuaru': a medicine used by caboclos river-dwellers of the Amazon, Amazonas, Brazil.

ETHNOPHARMACOLOGICAL RELEVANCE: 'Resin-of-canuaru' is a medicine utilized by caboclos living in the Amazon Region, Brazil. There is a mystery regarding its origin because the caboclos maintain that this substance is derived only from animal secretions (from a frog called canuaru), whereas the historic literature claims that 'resin-of-canuaru' is derived solely from a plant exudate (resin). Based on our ethnographic studies, we hypothesized that this substance is a combination of both. Because the past reports on this resiniferous material in the literature are based solely on observations, we aimed to present ethnographic, zoological and chemical data to try to elucidate the origin of the 'resin-of-canuaru'. MATERIALS AND METHODS: Ethnographic techniques and methods were applied, including participant observation, the use of field diaries and informal and unstructured interviews. The canuaru frog (Trachycephalus resinifictrix Goeldi, 1907) and 'resin-of-canuaru' were collected for taxonomic identification and chemical analysis, respectively. The resiniferous 'resin-of-canuaru' was extracted using MeOH and then analyzed by silica gel TLC and NMR. RESULTS: Canuaru frogs live in tree cavities and secrete a large amount of substances during spawning, resulting in a resiniferous material. NMR analysis of the MeOH extract of this crude material showed peaks assigned to 3,4-secofriedel-4(23)-en-3-oic acid (putranjuvic acid) and its methyl ester derivative (methyl putranjivate) and to biogenetic precursor of these two compounds (a lactone derivative), which is formed by the oxidation of friedelin. Based on evidence that Protium species accumulate primarily tetracyclic/pentacyclic triterpenoids and that the co-occurrence of the compounds listed above is rarely described in plant species, we suggest that these compounds could be products of the biotransformation of friedelin by the frog. CONCLUSIONS: According to our data, the 'resin-of-canuaru' seems to have both animal and vegetal origins.