Journal of Ethnopharmacology 145 (2013) 67–76 Contents lists available at SciVerse ScienceDirect Journal of Ethnopharmacology journal homepage: www.elsevier.com/locate/jep Plants as medicinal stressors, the case of depurative practices in Chazuta valley (Peruvian Amazonia) Jaume Sanz-Biset, Salvador Cañigueral n   Unitat de Farmacologia i Farmacognosia, Facultat de Farmacia, Universitat de Barcelona, Av. Joan XXIII, s/n, Barcelona E-08028, Catalonia, Spain a r t i c l e i n f o abstract Article history: Received 7 June 2012 Received in revised form 24 September 2012 Accepted 24 September 2012 Available online 30 October 2012 Ethnopharmacological relevance: Depurative practices, based on taking emetic plants and the restriction of food intake, are very much used in the traditional medicine of Chazuta (Peruvian Amazon) not only to restore health but also to maintain it. Aim of the study: To describe Chazuta’s depurative practices, within a theoretical framework that involves the stress system and which defines the role played by the medicinal plants used as medicinal stressors. This biomedical model is more inclusive in relation to the variety of medicinal uses found for these practices. Material and methods: The information was obtained in the valley of Chazuta from October 2004 to August 2005 through semi-structured interviews to the 6.3% of its rural adult population (i.e., 140 individuals, 75% belonging to the San Martin Quechua’s ethnic group). Thereafter, results were analysed and confronted to the existing literature. Results: Overall, 191 depurative practices were reported in Chazuta where 114 different plant species were recorded and identified. Depending on their level of severity and duration, depurative practices can be classified as mild or strict. The wide range of medicinal uses reported supports both the involvement of adaptive stress responses in depurative practices and the consideration of the plants employed in this practices as medicinal stressors. Conclusions: By inducing moderate stress within safe levels, depurative practices in Chazuta could produce adaptive responses that would protect against the detrimental consequences of chronic stress and stress-related diseases. This hypothesis could help to understand the diversity of the medicinal uses recorded in the field. Thus, plant remedies used in these practices in Chazuta could be considered as ‘‘medicinal stressors’’ as through vomiting the necessary neuroendocrine stress activation would be produced. In addition, other bioactivities that plants may harbour could converge with the whole stress reactivity process. & 2012 Elsevier Ireland Ltd. All rights reserved. Keywords: Medicinal plants Traditional medicine Chazuta Peruvian Amazon San Martin Quechuas Depuratives Vomiting Emesis Calorie restriction Fasting Stress Adaptive response Mitohormesis Medicinal stressor 1. Introduction The use of medicinal plants in Chazuta (Peruvian Amazon) has been the study subject of recent publications of our group (SanzBiset and Cañigueral, 2011; Sanz-Biset et al., 2009). A particular aspect highlighted by these works has been the wide use of plant remedies in what we have described as depurative practices. We use the term depurative to differentiate a group of practices in Chazuta that locals considered to be medicinal because it prompted a general cleansing effect. This cleansing effect was believed to be induced first by the ingestion of medicinal plants with emetic effects (sometimes also being purgative and often considered with other various medicinal n Corresponding author. Tel.: þ34 93 402 45 31; fax: þ 34 4035982. E-mail address: s.canigueral@ub.edu (S. Cañigueral). 0378-8741/$ - see front matter & 2012 Elsevier Ireland Ltd. All rights reserved. http://dx.doi.org/10.1016/j.jep.2012.09.053 effects) and second by reducing food intake. The local belief is that this depurative effect, whether induced by emetic medicinal plants and/or through calorie restriction, produces a ‘‘general cleansing’’ that enhances health broadly speaking. It is not uncommon for depurative practices to be used for bodily purification or detoxification in complementary and alternative medicine (Kayne, 2009). Nowadays, in medicine the term depurative is mainly used in the clinical management of poisoning and around the concept of dialysis, the method that removes waste and excess water from the blood in renal failure. However, in ethnopharmacology, the term depurative is often used to indicate medicinal plants with effects such as diuretic, purgative, perspirative, choleretic, cholagogue or emmenagogue. These have been reported in regions across the world among different historical periods (Gurib-Fakim, 2006). Some depurative practices that we reported in Chazuta were employed against different ailments prevalent in the region. 68 J. Sanz-Biset, S. Cañigueral / Journal of Ethnopharmacology 145 (2013) 67–76 For some of those, we found some correlation in between the medicinal uses reported and the available bibliographic data on plant bioactivity or active compounds (Sanz-Biset and Cañigueral, 2011). In part, those results may explain the use of plants in some depurative practices due to plant activities such as antinflammatory and antimicrobial. Indeed, besides the emetic effect, local informants also considered many other medicinal effects for the plants employed in these practices. However, in many occasions depurative practices in Chazuta were generally employed to tone and strengthen the body. When we faced these more unspecific medicinal uses, we found ourselves limited with the conventional approach of targeting precise biological activities or active compounds, as there this relationship became less clear. Therefore, we were led to consider other biomedical models that could explain the broad spectrum of the physiological effects reported. As a result, the explanation proposed here relates to the moderate activation of stress responses. The theoretical framework used to support these explanations is described in Appendix A (see the supplementary file). To sum up, it is known that both emesis and calorie restriction stimulate the neuroendocrine activation of the stress system (Eversmann et al., 1978, Masoro, 1998). As Chazuta’s depurative practices mimic two very primitive and really stressful conditions that human beings can be encountered with, i.e., intoxication and starvation, it is feasible to consider the induction of moderate stress in a way that is medicinal. Considering models of beneficial exposure to stress is common in the study of physical exercise, diet restriction and other conditions (Jackson and Dishman, 2006; Sinclair, 2005; Tapia, 2006). Similarly to physical activity, depurative practices in Chazuta could elicit an adequate stimulation of the stress system, activating several centres such as the HPA axis, the autonomic nervous system and certain centres in the CNS. This activation could be within safe levels and could produce the corresponding adaptive responses conducive to beneficial stress resistance effects in different systems, e.g., gastrointestinal, endocrine, cardiovascular, respiratory or immune (Chrousos, 2006; Tsigos and Chrousos, 2002; Fig. 1). Plant preparation Then, plant remedies used in depurative practices in Chazuta could be considered as ‘‘medicinal stressors’’ as through vomiting they could prompt the necessary stress to trigger adaptive stress responses. In addition, other bioactivities that plants are known to harbour could converge with the whole stress reactivity process. The aim of this paper is to describe Chazuta’s depurative practices within this more inclusive theoretical framework of adaptive stress responses that is able to indicate the biological processes that would explain the variety of medicinal uses found for these practices; and ultimately, to clarify the role that medicinal plants play in these practices as medicinal stressors. The present paper also brings data to the topic of plants and practices used for depuration, purification or detoxification. Even though this is a common subject in complementary and alternative medicine, papers rarely focus on it. Hence, ethnopharmacological data on this area is especially interesting and can prove to be useful in future studies. 2. Methods The information collected in the field was obtained through semi-structured interviews to the 6.3% of the district’s rural adult population (140 individuals, 60% men, 40% women, 75% of which was considered Quechua). The data presented in this paper is based in a wider fieldwork performed in the studied region from October 2004 to August 2005. In a previous published paper about the medicinal plants of Chazuta (Sanz-Biset et al., 2009), precise information was already given on the study site, its ethnicity, the demography, its socio cultural context, the historical background, the present medical system of Chazuta, how the selection of informants was done for the study, the type of interviews used, how plants were collected, which botanists participated in determining plant species, and how local consent for the investigation in Chazuta was obtained. Moreover, permit for the collection and exportation of voucher herbarium specimens was covered by official authorisations issued by the Agricultural Ministry of Peru’s INRENA: Collection licence 087–2004-INRENA-IFFS-DCB and Exportation permit 005780-AG-INRENA. Emesis Calorie restriction Stress Neuroendocrine activation e.g. Several centres are activated HPA axis ANS Dopaminergic system Amygdale Hippocampus Arcuate nucleus Thermoregulatory and appetite-satiety centres Other ... Glucocorticoids, catecholamines, ACh, neuropeptides, ATP, NO, HSP, transcriptional factors, others Modulation of biological activities in different systems GI system Endocrine axes: reproductive, growth, thyroid, metabolic Behaviour Cardiovascular, respiratory and renal functions Immune system Fig. 1. Neuroendocrine infrastructure triggered by stress which could be activated by depurative practices in Chazuta valley. ACh: acetylcholine, ANS: autonomic nervous system, ATP: adenosine triphosphate, AVP: arginine vasopressin, CRH: corticotropin-releasing hormone, GI: gastrointestinal, HPA: hypothalamic–pituitary–adrenal, HSP: heat-shock proteins, NO: nitric oxide. J. Sanz-Biset, S. Cañigueral / Journal of Ethnopharmacology 145 (2013) 67–76 Results obtained in the field were thereafter analysed and confronted to the existing literature. 3. Results and discussion In this section, results are shown and discussed in the following sequence. First, quantitative results obtained in recording depurative practices in Chazuta valley are given. Then, depuratives practices are described whether considered being mild or strict depending on their severity and duration. Also, the different medicinal uses reported are shown. Finally, the function of plants in depurative practices is discussed. 3.1. Depurative practices reported in Chazuta On the whole, 318 plant species used for medicinal purposes by people living in the Chazuta district were collected and identified. Of these, 114 species were found to be used in 191 depurative practices recorded in the survey. Most of the plant remedies observed to be taken in depurative practices in Chazuta, were aqueous extracts, often unbearably bitter, highly unpleasant to drink, which seemed to act mainly as irritants of the gastric and intestinal mucosa triggering nausea conducive to emesis (Fig. 2). The usual drastic vomiting caused by the herbal preparations administered in depurative practices in Chazuta, naturally brings the need to follow a more constrained food and behavioural regime (known as dieta in Chazuta). This can go from simply restricting some types of food, to becoming so strict that could 69 even imply fasting. In the cases where fasting was present, salt limitation and rest in social seclusion was also prescribed. Also, the use of emetic plants as well as the depurative practices themselves can be more or less prolonged in time. From having just a single cup of the squeezed juice of Aristolochia leuconeura’s leaves, to drink every morning for seven days a litre of a decoction made from Tabernaemontana sananho’s root barks. Also, the calorie restriction prescribed can be less-or-more severe and extended in time. Normally, the prolonged the emesis, the stronger the calorie restriction and the whole regime is. Due to their severity and length in time, depurative practices can be clearly classified either as mild or strict. 3.2. Mild depurative practices. These practices are characterised by a moderate calorie restriction that never reaches fasting, where neither seclusion nor the restriction of the ingestion of salt are prescribed. They are generally short in time, many lasting just one day where only a single dose of a plant remedy is taken. In total, we recorded 93 reports of mild depurative practices, which are shown in Table 1. The remedy most reported (35 times) in these shorter depurative practices was the worldwide famous ayahuasca mixture, made with the decoction of Banisteriopsis caapi stems with Psychotria viridis leaves, and sometimes (16 reports) also adding other plant species. In comparison with other areas of the Peruvian Amazon, we observed that the traditional ingestion of these mixtures hardly entailed any complex ritual. As mentioned by Lamb (1985), it seems that even more than half a century ago, Chazuta’s medicine men were not familiar with managing the psychotropic effects commonly experienced with ayahuasca. Nowadays, it is difficult to track the original use of ayahuasca since its tourist boom experienced in recent years has spread throughout the country. Even a bar recently opened in the valley was named as Ayahuasca, and there is a thriving tourist industry in the region based on offering ayahuasca trips into the jungle. The use of ayahuasca that we reported in Chazuta, differs from what is shown in many other studies of other regions of western Amazonia (Baer, 1979; Cárdenas-Timoteo, 1989; Chaumeil, 1979; Fericgla, 1994; Luna, 1986). In Chazuta, it looks like as if this plant mixture has been included into the local repertoire of purgas. In a few occasions, we observed traditional healers giving out ayahuasca mixtures to patients. Except in those healers that had been already in contact with westerners that searched for ‘‘trips’’, the remedy was dispensed as another purga where the main goal was to produce that cleansing effect, i.e., the depurative effect. Thus, the healers did not expect any psychotropic effect rather than a simple mareacion, i.e., sickness conducive to vomiting. It is obvious that the international popularity of ayahuasca arrived years ago in this valley, however, and at least until recently, this trend seemed to have adapted and shaped quite well into the local traditional medical system, using ayahuasca more as a depurative than a psychotropic. Most likely, ayahuasca could have been introduced relatively recently in Chazuta’s ethnomedicine and the high number of reports found explained by the external pressure. Acculturation in these regions advances fast and it is likely that such a fragile environment in front of such a strong western current would quickly put ordinary farmers into singing in the middle of the night in a high, wearing condor feathers and jaguar tooth, which sincerely, it is hard to say considering the first one original, which one of the three specimens is more extinct. 3.3. Strict depurative practices Fig. 2. The act of vomiting, which is highly regarded in the ethnomedicine of Chazuta valley. Strict depurative practices are characterised by a severe calorie restriction, usually leading to fasting. In these cases, both social 70 Table 1 Plant remedies used in mild depurative practices in Chazuta valley (Peruvian Amazon). Scientific name (botanical family) (C ¼ cultivated and/or W ¼wild) (voucher herbarium specimen) Local name Part(s) used Unspecific use reportsa Nn:repeated reportsa Specific use reports Nn:repeated reports Mode of preparation (administration is oral) Ardisia guyanensis (Aubl.) Mez (Myrsinaceae) (W) (BCN 40225) Aristolochia leuconeura Linden (Aristolochiaceae) (C) (BCN 40090) Puka chakruna Leaf 1 0 Decocted with Banisteriopsis caapi stems Yawar panka, Machakuy Leaf or Omagway waska, Wankawi sacha 4 Squeezed, the juice obtained is drunk 10þ 1n 11 Cough (5), Bronchitis (5), Tobacco and cocaine addiction (1) 1 Tobacco and cocaine addiction. (1) 5 For hunting and fishing preparednessb (3), Stomach pains (2) 0 1 1 1 1 Rheumatism (1) Rheumatism (1) 1 1 Lumbago (1) 1n 1n Tobacco and cocaine addiction (1n) 1n Lumbago (1n) 1 Brugmansia suaveolens (Humb. & Bonpl. ex Willd.) Bercht. & J. Presl (Solanaceae) (C) (BCN 40186) Brunfelsia grandiflora subsp. grandiflora (Solanaceae) (C) (BCN 40340) Calliandra angustifolia Spruce ex Benth. (Fabaceae) (C) (BCN 40154) Cornutia microcalycina Pav. & Moldenke (Verbenaceae) (C and W) (BCN 40316) Couroupita guianensis Aubl. (Lecythidaceae) (C) (BCN 40136) Croton draconoides Müll. Arg. (Euphorbiaceae) (W) (BCN 40216) Gonzalagunia cornifolia (Kunth) Standl. (Rubiaceae) (W) (BCN 40275) Guarea macrophylla Vahl (Meliaceae) (C) (BCN 45069) Himatanthus sucuuba (Spruce ex Müll. Arg.) Woodson (Apocynaceae) (C) (BCN 40862) Hura crepitans L. (Euphorbiaceae) (W) (BCN 40265) Jatropha curcas L. (Euphorbiaceae) (C) (BCN 40263) Jatropha gossypiifolia L. (Euphorbiaceae) (C) (BCN 40264) Kalanchoe pinnata (Lam.) Pers. (Crassulaceae) (W) (BCN 40358) Ayawaska, Ayawaska negra, Ayawaska amarilla, Purgawaska Stem 14 Toe, Toe de flor blanca Leaf 1n Chirik sanango Root bark 4 Bobensana Stem 1n Shinkurisacha Leaf 1n Aya uma Bark 1n Bark n 1 n Decocted with Psychotria viridis leaves Decocted: w/ Ardisia guyanensis leaves (1n), w/ Psychotria alba leaves (1), w/ P. carthagenensis leaves (1), w/ P. ernestii leaves (1), w/ P. viridis and Gonzalagunia cornifolia (2), w/ P. viridis and Petiveria alliacea (2), w/ P. viridis and Pterocarpus rohrii(2) w/P. viridis, Rosenbergiodendron longifolium and Toxosiphon trifoliatus (1) Decocted with Psychotria viridis, Mansoa alliacea and Piper callosum Decocted w/ Psychotria viridis, P. carthagenensis, Cornutia microcalycina, Croton draconoides, Himatanthus sucuuba, Licaria sp., Mikania sp. and Virola calophylla Decocted w/ Psychotria viridis, P. alba, Brugmansia suaveolens, Calliandra angustifolia, Couroupita guianensis, Tovomita aff. stylosa and Zygia longifolia Decocted with Psychotria viridis and Aristolochia leuconeura Decocted with Banisteriopsis caapi, Psychotria viridis, P. alba, Calliandra angustifolia, Couroupita guianensis, Tovomita aff.stylosa and Zygia longifolia 11 Febrifuge (7), For hunting Macerated in fresh water for some minutes and fishing preparednessb (4) n 1 Lumbago (1n) Decocted with Banisteriopsis caapi, Psychotria viridis, P. alba, Brugmansia suaveolens, Couroupita guianensis, Tovomita aff.stylosa and Zygia longifolia n n 1 Rheumatism (1 ) Decocted w/ Banisteriopsis caapi, Psychotria viridis, P.carthagenensis, Croton draconoides, Himatanthus sucuuba, Licaria sp., Mikania sp. and Virola calophylla 1n Lumbago (1n) Pichana sacha, Pichana kaspi, Yaku lucero Requia Aerial part 2 0 Decocted with Banisteriopsis caapi, Psychotria viridis, P. alba, Brugmansia suaveolens, Calliandra angustifolia, Tovomita aff. stylosa and Zygia longifolia Decocted with Banisteriopsis caapi, Psychotria viridis, P. carthagenensis, Cornutia microcalycina, Himatanthus sucuuba, Licaria sp., Mikania sp. and Virola calophylla Decocted with Banisteriopsis caapi stems and Psychotria viridis leaves Bark 2 0 Decoction Bellaco kaspi Bark 2 2 1n 1n Rheumatism (1n) Sangre de grado 1 n n Rheumatism (1 ) Vermifuge (2) Decoction Catahua Latex 2 2 Piñon blanco Leaf & seed 2 0 Boiled with Banisteriopsis caapi, Psychotria viridis, P.carthagenensis, Cornutia microcalycina, Croton draconoides, Licaria sp., Mikania sp. and Virola calophylla A small dose of the crude latex is drunk. This remedy is considered very toxic if overdose occurs. Squeezed, the juice obtained is drunk Piñon colorado Leaf & seed 2 0 Squeezed, the juice obtained is drunk Rakta panka, Aire sacha Leaf 1 1 Vermifuge (2) Pain when passing water Squeezed, then a great quantity of the juice obtained needs to be taken (1) J. Sanz-Biset, S. Cañigueral / Journal of Ethnopharmacology 145 (2013) 67–76 Banisteriopsis caapi (Spruce ex Griseb.) C.V. Morton (Malpighiaceae) (C) (BCN 40135) Decocted with Banisteriopsis caapi stems and Psychotria viridis leaves Licaria sp. (Lauraceae) (W) (BCN 40116) Mansoa alliacea (Lam.) A.H. Gentry (Bignoniaceae) (C and W) (BCN 40100) Mikania sp. (Asteraceae) (C)(JSB-513) c Minquartia guianensis Aubl. (Olacaceae) (W) (BCN 40145) Petiveria alliacea L. (Phytolaccaceae) (C) (BCN 40892) Piper callosum Ruiz & Pav. (Piperaceae) (C and W) (BCN 40846) Psychotria alba Ruiz & Pav. (Rubiaceae) (W) (BCN 40291) Canela Bark 1n 1n Rheumatism (1n) Ajo sacha, Ajo sacha macho, Ajo sacha hembra Sinchi toe Stem and root bark 2 2 Aerial part 1n 1n 1n 1n Huacapú Bark 5 0 Decocted with Banisteriopsis caapi, Psychotria viridis and Piper callosum leaves Decocted with Banisteriopsis caapi, Psychotria viridis, P. carthagenensis, Cornutia microcalycina, Croton draconoides, Himatanthus sucuuba, Licaria sp. and Virola calophylla Decoction (in 3 reports), Macerated in fresh water for some minutes (in 2 reports) Mukura hembra, Mukura macho Guayusa macho or hembra Chakruna n For hunting and fishing preparedness b (2) Rheumatism (1n) Rheumatism (1n) Decocted with Banisteriopsis caapi, Psychotria viridis, P.carthagenensis, Cornutia microcalycina, Croton draconoides, Himatanthus sucuuba, Mikania sp. and Virola calophylla Macerated in fresh water for some minutes 2 0 Decocted with Banisteriopsis caapi and Psychotria viridis Leaf 1n 1n Rheumatism (1n) Decocted with Banisteriopsis caapi, Psychotria viridis and Mansoa alliacea Leaf 1n 1n 0 1n Lumbago (1n) Decocted with Banisteriopsis caapi stems Decocted with Banisteriopsis caapi, Psychotria viridis, Brugmansia suaveolens, Calliandra angustifolia, Couroupita guianensis, Tovomita aff. stylosa and Zygia longifolia Decocted with Banisteriopsis caapi stems Decocted with Banisteriopsis caapi, Psychotria viridis, Cornutia microcalycina, Croton draconoides, Himatanthus sucuuba, Licaria sp., Mikania sp. and Virola calophylla Decocted with Banisteriopsis caapi stems Psychotria carthagenensis Jacq. (Rubiaceae) (C and W) (BCN 40292) Yaku bushiklla, Chakruna Leaf 1n 1n 0 1n Rheumatism (1n) Psychotria ernestii K. Krause (Rubiaceae) (W) (BCN 40294) Psychotria viridis Ruiz & Pav. (Rubiaceae) (C) (BCN 40296) Chakruna Leaf 1n 0 Chakruna, Chakruna negra Leaf 21n 1n 5n For hunting and fishing preparedness b (3n), Stomach pains (2n) 1n Rheumatism (1n) 1n 1n 1n Rheumatism (1n) 1n Lumbago (1n) 1n 1n Tobacco & cocaine addiction (1n) 0 Decocted with Banisteriopsis caapi stems and Psychotria viridis leaves 0 Decocted with Banisteriopsis caapi, Psychotria viridis and Toxosiphon trifoliatus 1n Lumbago (1n) Decocted w/ Banisteriopsis caapi, Psychotria viridis, P. alba, Brugmansia suaveolens, Calliandra angustifolia, Couroupita guianensis & Zygia longifolia Decocted w/ Banisteriopsis caapi, Psychotria viridis & Rosenbergiodendron longiflorum Pterocarpus rohrii Vahl (Fabaceae) (C) (BCN 40159) Rosenbergiodendron longiflorum (Ruiz & Pav.) Fagerl. (Rubiaceae) (W) (BCN 40304) Tovomita aff. stylosa Hemsl. (Clusiaceae) (W) (BCN 44882) Toxosiphon trifoliatus (Pilg.) Kallunki (Rutaceae)(W)(JSB-145) c Virola calophylla (Spruce) Warb. (Myristicaceae) (W) (BCN 40115) Zygia longifolia (Humb. & Bonpl. ex Willd.) Britton & Rose (Fabaceae) (W) (BCN 44887) 2n Yawar kaspi Bark Lucero sacha Whole plant 1n Bachuja, Chullachaki Bark 1n kaspi/ hembra Lucero sisa, Lucero sacha Whole plant 1n 0 Bark 1n 1n Rheumatism (1n) Yaku or Untai shimbillu, Bark Shimbillu 1n 1n Lumbago (1n) Cumala roja Decocted: w/ Banisteriopsis caapi (19n), w/ B. caapi & Gonzalagunia cornifolia (2n), w/ B. caapi & Petiveria alliacea (2n), w/ B. caapi & Pterocarpus rohrii (2n), w/ B. caapi, Rosenbergiodendron longifolium & Toxosiphon trifoliatus (1n) Decocted with Banisteriopsis caapi, Cornutia microcalycina, Croton draconoides, Himatanthus sucuuba, Licaria sp., Mikania sp., Psychotria carthagenensis and Virola calophylla Decocted with Banisteriopsis caapi, Mansoa alliacea and Piper callosum Decocted with Banisteriopsis caapi, Brugmansia suaveolens, Calliandra angustifolia, Couroupita guianensis, Psychotria alba, Tovomita aff. stylosa and Zygia longifolia Decocted with Banisteriopsis caapi and Aristolochia leuconorrea Decocted w/ Banisteriopsis caapi, Psychotria viridis, P. carthagenensis, Cornutia microcalycina, Croton draconoides, Himatanthus sucuuba, Licaria sp. & Mikania sp. Decocted w/ Banisteriopsis caapi, Psychotria viridis, P. alba, Brugmansia suaveolens, Calliandra angustifolia, Couroupita guianensis & Tovomita aff. Stylosa J. Sanz-Biset, S. Cañigueral / Journal of Ethnopharmacology 145 (2013) 67–76 Aerial part a Unspecific use reports were those which informants considered that the cleansing effect produced by depurative practices brought a general and unspecific tonic effects (see Table 3). In Chazuta, it was common to endure depurative practices to achieve the necessary fitness to go out in hunting and fishing expeditions. Moreover, through the depurative effect most of the corporal scent was expected to disappear, hence making human presence unnoticeable for wild animals which then become easier whether to hunt or fish. c BCN codes unavailable. Instead, the collection number, i.e., Jsb-xxx, is provided. If needed, a duplicate must be found in USM (Lima, Peru), where these specimens were yet to be entered. b 71 72 Table 2 Plant remedies used in strict depurative practices in Chazuta valley (Peruvian Amazon). Scientific name (C¼ cultivated and/or W¼ wild) (voucher herbarium specimen) Local name Aspidosperma rigidum Rusby Tashkum remo kaspi, Remo kaspi (Apocynaceae) (W) (BCN 40686) Ayawaska negra, A. amarilla, Purgawaska Banisteriopsis caapi (Spruce ex Griseb.) C. V. Morton (Malpighiaceae) (C) (BCN 40135) Specific use reportsn Nn: repeated reports Mode of preparation (Administration is oral) Decocted with the root bark of Tabernaemontana undulata Bark 1 0 Stem 0 1 Pulmonary disease (1) Decocted with Psychotria viridis leaves Manchinga Latex 0 3 Chirik sanango Root bark 1 13 Rheumatism (12), Inguinal herniab (1) Shillinto blanco, Shillinto negro Stem 1 4 Guayusa macho Ullku guayusa Parinari Leaf 1 0 Bark 0 1 Munichi sacha Leaf 2 0 Decoction Millwa renaquillo, Millwa renaco, M.r. macho, M.r. hembra, M.r. de hoja ancha, M.r. de hoja pequeña Mishki panka Bark 1 0 Decoction Leaf 0 1 For hunting and fishing preparednessd (1) Infusion, for drinking and, in addition, bathing 8 Rheumatism (8) Macerated in fresh water Chuchuwasha Chuchuwasha Blanca 1 Stem and root bark Bark 0 2 Inguinal herniab (1), Broken bones (1) Macerated in fresh water Stem 0 1 Inguinal herniab (1) Decoction 0 1 Malaria (1) Infusion Guayusa macho, Guayusa hembra Whole plant Leaf 2 0 Yanchama blanca, Yanchama negra Latex 0 1 Heliconia acuminata Rich. (Heliconiaceae) (W) (BCN 40361) Mansoa alliacea (Lam.) A.H. Gentry Ajo sacha macho/ hembra (Bignoniaceae) (C and W) (BCN 40100) Maytenus aff. macrocarpa (Ruiz & Pav.) Briq. (Celastraceae) (W) (BCN 40217/ 40218) Phthirusa stelis (L.) Kuijt (Loranthaceae) (C) (BCN 40133) Physalis angulata L. (Solanaceae) (W) (BCN 40877) Piper callosum Ruiz & Pav. (Piperaceae) (C and W) (BCN 40846) Poulsenia armata (Miq.) Standl. (Moraceae) (W) (BCN 40578) Psychotria viridis Ruiz & Pav. (Rubiaceae) (C) (BCN 40296) Remijia megistocaula K. Krause (Rubiaceae) (W) (BCN 40270) Renealmia aromatica (Aubl.) Griseb. (Zingiberaceae) (W) (BCN 40836) Smilax longifolia Rich. (Smilacaceae) (W) (BCN 40850) Strychnos ramentifera Ducke (Loganiaceae) (W) (USM 206354) Unspecific use reportsa Nn: repeated reports a Suelda con suelda de hoja menuda, Pishku isman de hoja menuda Bolsa mullaka Rheumatism (3) One spoonful of the latex is mixed with warm water Macerated in fresh water Abscess (1), Leishmaniosisc (1), Tumors (1), AIDS (1) The crushed stem, (sometimes previously roasted), is macerated in fresh water. Normally, a single dose is given Infusion Tumors (1) Decocted with Remijia megistocaula, Smilax longifolia and Trichilia maynasiana Infusion n Rheumatism (1) A few spoonfuls are mixed with warm water n Pulmonary disease (1 ) Chakruna, Chakruna negra Leaf 0 1 Capirona blanca Bark 0 1n Tumors (1n) Ñukñuk panka Leaf 0 1 Zarza, Zarzaparrilla Root 0 1n Tumors (1n) Suifa, Waska chuchuwasha Stem 0 1 For hunting and fishing preparednessd (1) Malaria (1) Decocted with crushed stems of Banisteriopsis caapi Decocted with Couepia chrysocalyx, Smilax longifolia and Trichilia maynasiana Infusion, for drinking and, in addition, bathing Decocted with Couepia chrysocalyx, Remijia megistocaula and Trichilia maynasiana. Decoction J. Sanz-Biset, S. Cañigueral / Journal of Ethnopharmacology 145 (2013) 67–76 Brosimum alicastrum subsp. bolivarense (Pittier) C.C. Berg (Moraceae) (C and W) (BCN 40699) Brunfelsia grandiflora subsp. grandiflora (Solanaceae) (C) (BCN 40340) Callaeum antifebrile (Griseb.) D. M. Johnson (Malpighiaceae) (C and W) (BCN 40246) Calyptranthes bipennis O. Berg (Myrtaceae) (C) (BCN 40119) Couepia chrysocalyx (Poepp.) Benth. ex Hook. f. (Chrysobalanaceae) (W) (BCN 44897) Esenbeckia amazonica Kaastra (Rutaceae) (W) (BCN 40831) Ficus trigona L.f. (Moraceae) (C and W) (BCN 40702) Part used Strychnos solimoesana Krukoff (Loganiaceae) (W) (USM 206381) Tabernaemontana sananho Ruiz & Pav. (Apocynaceae) (C and W) (BCN40859) Tabernaemontana undulata Vahl (Apocynaceae) (C and W) (BCN 40725) Tovomita brasiliensis (Mart.) Walp. (Clusiaceae) (W) (BCN 45070) Tovomita aff. stylosa Hemsl. (Clusiaceae) (W) (BCN 44882) Suifa, Waska chuchuwasha Stem 0 1 Rheumatism (1) Decoction b 5 5 Rheumatism (3), Inguinal hernia (1), Vermifuge (1) Macerated in fresh water 1 1n 0 3 0 1 Rheumatism (2), Malaria (1) Bachuja, Chullachaki kaspi, C. k. macho Root bark Root bark Bark Bachuja, Chullachaki kaspi, C. k. hembra Bark 17 Bark 0 17 Rheumatism (7), Broken bones (5), Abscess (1), Inguinal herniab (1), Leishmaniosisc (1), Vaginal pains (1), Urine infection (1) 1n Tumors (1n) Uchu sanango Ushpawasha sanango, Ayac sanango Trichilia maynasiana C. DC. (Meliaceae) Shatunillu (W) (BCN 44884) Rheumatism (1) Decocted or macerated in fresh water. Decocted with the bark of Aspidosperma rigidum. Macerated with other plants to conform a particular Bachuja mixturee. Decocted (18) or macerated in fresh water (16), with other plants to conform the plant mixture known as Bachujaf. Decocted with Couepia chrysocalyx, Remijia megistocaula and Smilax longifolia. a Unspecific use reports were those which informants considered that the cleansing effect produced by depurative practices brought a general and unspecific tonic effect (see Table 3). We consider that the disorder known in Chazuta as bajada de testos (descendent testicles) refers to inguinal hernia. It is a much prevalent ailment among ‘‘Chazutian’’ men that is usually caused when carrying heavy weights. c We consider that the disease known in Chazuta as uta refers to leishmaniosis. Even though it is rare in Chazuta, individuals who spend days deep inside the forest (normally involved in illegal tree felling) are especially prone to leishmania infection. d In Chazuta, it was common to endure depurative practices to achieve the necessary fitness to go out in hunting and fishing expeditions. Moreover, through the depurative effect most of the corporal scent was expected to disappear, hence making human presence unnoticeable for wild animals which then become easier whether to hunt or fish. e This particular Bachuja mixture is prepared by macerating the bark of Tovomita brasiliensis with the following plants: Calliandra angustifolia Spruce ex Benth. (Fabaceae) (BCN 40154) (1 report), Clusia aff. palmicida Rich. ex Planch. and Triana (Clusiaceae) (BCN 44874) (1), Erythroxylum sp. (Erythroxylaceae) (BCN 40234) (1), Ficus nymphaeifolia Mill. (Moraceae) (BCN 40638) (1), Ficus vs. paraensis (Miq.) Miq. (Moraceae) (BCN 40711) (1), Ficus ypsilophlebia Dugand (Moraceae) (BCN 40580) (1), Tovomita cf. longifolia (Rich.) Hochr. (Clusiaceae) (BCN 44878) (1) and Zygia longifolia (Humb. and Bonpl. ex Willd.) Britton and Rose (Fabaceae) (BCN 44887) (1). f Bachuja mixtures are either macerations in fresh water or decoctions of Tovomita aff. stylosa bark with the following plants: Tovomita foldatsii Cuello (Clusiaceae) (BCN 44883) (29 reports), Calliandra angustifolia Spruce ex Benth. (Fabaceae) (BCN 40154) (20), Maytenus aff. macrocarpa (Ruiz & Pav.) Briq. (Celastraceae) (BCN 40217/40218) (13), Zygia longifolia (Humb. & Bonpl. ex Willd.) Britton & Rose (Fabaceae) (BCN 44887) (13), Allosanthus trifoliolatus Radlk. (Sapindaceae) (BCN 40140) (12), Petrea sp. (Verbenaceae) (BCN 40266) (12), Clusia aff. lineata (Benth.) Planch. & Triana (Clusiaceae) (BCN 44873) (10), Dicranopygium aff. lugonis Harling (Cyclanthaceae) (BCN 40083) (10), Dicranopygium yacu-sisa Harling (Cyclanthaceae) (BCN 40082) (10), Rourea puberula Baker (Connaraceae) (BCN 40691) (7), Ficus trigona L.f. (Moraceae) (BCN 40702) (6), Clusia aff. loretensis Engl. (Clusiaceae) (BCN 44872) (4), Salacia cordata (Miers) Mennega (Celastraceae) (BCN 40566) (4), Ficus caballina Standl. (Moraceae) (BCN40710) (3), Ruellia proxima Lindau (Acanthaceae) (BCN 40220) (3), Ardisia huallagae Mez (Myrsinaceae) (BCN 40226) (2), Clusia sp.2. (Clusiaceae) (JSB24)g (2), Clusia sp.3. (Clusiaceae) (USM 207186) (2), Clusia sp.4. (Clusiaceae) (JSB-261)g (2), Eugenia biflora (L.) DC. (Myrtaceae) (BCN 40110) (2), Ficus casapiensis (Miq.) Miq. (Moraceae) (BCN 40647) (2), Aspidosperma rigidum Rusby (Apocynaceae) (BCN 40686) (1), Asplundia sp. (Cyclanthaceae) (JSB263)g (1), Capparis sola J.F. Macbr. (Capparaceae) (BCN 46106) (1), Carpotroche aff. longifolia (Poepp.) Benth. (Flacourtiaceae) (BCN 40258) (1), Casearia sp. (Flacourtiaceae) (BCN 40087) (1), Chomelia paniculata (Bartl. ex DC.) Steyerm. (Rubiaceae) (BCN 40305) (1), Chrysochlamys ulei Engl. (Clusiaceae) (BCN 40227) (1), Clusia aff. flavida (Benth.) Pipoly (Clusiaceae) (BCN 45073) (1), Clusia aff. palmicida Rich. ex Planch. & Triana (Clusiaceae) (BCN 44874) (1), Clusia sp.1. (Clusiaceae) (JSB271)g (1), Clusia sp.5. (Clusiaceae) (JSB-469)g (1), Condaminea corymbosa (Ruiz & Pav.) DC. (Rubiaceae) (BCN40271) (1), Copaifera paupera (Herzog) Dwyer (Fabaceae) (BCN 40153) (1), Coussarea brevicaulis K. Krause (Rubiaceae) (BCN 40310) (1), Doliocarpus aff. dentatus (Aubl.) Standl. (Dilleniaceae) (BCN 40192) (1), Ficus americana subsp. guianensis (Desv. ex Ham.) C.C. Berg (Moraceae) (USM 206345) (1), Ficus eximia Schott (Moraceae) (BCN 40697) (1), Ficus macbridei Standl. (Moraceae) (BCN 40696) (1), Ficus vs. maxima Mill. (Moraceae) (BCN 40639) (1), Ficus obtusifolia Kunth. (Moraceae) (BCN 208763) (1), Ficus pertusa L.f. (Moraceae) (BCN 40694) (1), Ficus tonduzii Standl. (Moraceae) (BCN 40648) (1), Ficus ypsilophlebia Dugand (Moraceae) (BCN 40580) (1), Forsteronia graciloides Woodson (Apocynaceae) (BCN 40684) (1), Garcinia madruno (Kunth) Hammel (Clusiaceae) (JSB-139)g (1), Heteropsis flexuosa (Kunth) G.S. Bunting (Araceae) (BCN 40328) (1), Hevea guianensis Aubl. (Euphorbiaceae) (BCN 40260) (1), Hippotis tubiflora Spruce ex K. Schum. (Rubiaceae) (BCN 40277) (1), Inga ruiziana G. Don (Fabaceae) (BCN 44889) (1), Inga semialata (Vell.) Mart. (Fabaceae) (BCN 44885) (1), Marcgravia cf. crenata Poepp. ex Wittm. (Marcgraviaceae) (JSB-250)g (1), Matelea rivularis Woodson (Asclepiadaceae) (BCN 40332) (1), Maxillaria sp. (Orchidaceae) (JSB-159)g (1), Phthirusa stelis (L.) Kuijt (Loranthaceae) (BCN 40133) (1), Psittacanthus cucullaris (Lam.) Blume (Loranthaceae) (BCN 40313) (1), Psychotria carthagenensis Jacq. (Rubiaceae) (BCN 40292) (1), Rinorea viridifolia Rusby (Violaceae) (BCN 46108) (1), Sida setosa Mart. ex Colla (Malvaceae) (BCN 44891) (1), Solanum monadelphum Van Heurck & Müll. Arg. (Solanaceae) (JSB-259)g (1), Strychnos ramentifera Ducke (Loganiaceae) (USM 206354) (1), Swartzia arborescens (Aubl.) Pittier (Fabaceae) (BCN 40173) (1), Swartzia simplex (Sw.) Spreng. (Fabaceae) (W) (BCN 40172) (1), Tovomita carinata Eyma (Clusiaceae) (BCN 44877) (1), Toxosiphon trifoliatus (Pilg.) Kallunki (Rutaceae) (JSB-145)g (1) and Unonopsis sp. (Annonaceae) (W) (BCN 40720) (1). g BCN and USM codes unavailable. Instead, the collection number, i.e., Jsb-xxx, is provided. If needed, a duplicate must be found in USM (Lima, Peru), where these specimens were yet to be entered. b J. Sanz-Biset, S. Cañigueral / Journal of Ethnopharmacology 145 (2013) 67–76 73 74 J. Sanz-Biset, S. Cañigueral / Journal of Ethnopharmacology 145 (2013) 67–76 seclusion and the restriction of the ingestion of salt are often prescribed. They are longer in time than mild depurative practices and usually a plant remedy is ingested multiple times. For this second type of depurative practices, which are shown in Table 2, we obtained 98 reports. These more severe depurative practices are known as strict diets and have been the study subject in a previous paper (SanzBiset and Cañigueral, 2011). Informants stressed that the intention to take emetic remedies and to fast was again to produce this general cleansing effect considered medicinally beneficial by itself. It is common sense to see that the rejection of salt in such regimes may participate in the depurative effect as this restriction clearly enhances diuresis as well as other corporal secretions such as perspiration. The plant remedy known by informants as either bachuja or mezcla de palos was the most reported (34 times) in the survey for being taken in strict diets. It is a plant mixture that always contain species of the genus Tovomita (Clusiaceae) (Fig. 3) and which locals consider as the panacea of Chazuta. 3.4. Uses of depurative practices and the function of plants Depurative practices in the traditional medicine of Chazuta are used either to restore health or to maintain it. Even though we expected informants to bring in strong irrational beliefs to explain the function of their vomiting and starvation practices, the main argument they put forward persistently was the concept that cleansing, whether through emesis or by restricting food, was salutiferous. In addition, in Chazuta informants also stressed that if plants were to be used for curing, the necessary dieta was needed to be followed. In some occasions, fasting was said to be the main cure and plant remedies just used to complement it. In a way, the fact that vomiting and starving was not avoided but desired, left us puzzled at the beginning, as it seemed to contradict our conventional western medical beliefs on health and healing. Depurative practices reported in Chazuta were employed against different ailments prevalent in the region. The most common diseases in Chazuta have an infectious aetiology due to the tropical climate and lack of sewer systems. Musculoskeletal ailments are also frequent, due to the rural lifestyle. However, in many occasions depurative practices were employed to tone and strengthen the body, thus to cope better with the labour of being a chacarero (farmer), montaraz (hunter) and mitayero (rural worker in general). These terms partially compile the region’s view of a capable, strong and healthy individual, i.e., someone able to sustain his/her family and clan, which until recently mainly depended upon the food harvested from the orchards, the animals hunted in the jungle and fished in the rivers, as well as upon the maintenance of a certain social balance (Salas-Fasabi, 2001; Weiss, 1949). It is considered that the cleansing produced by these practices brings a more general tonic effect expressed in Chazuta in ways such as: (a) augmenting work performance, (b) enhancing endurance (hacerse más bizarro), (c) increasing weight carrying, (d) extending cold resistance, (e) sharpening the senses, (f) lessening sluggishness (dejar de ser arragán), (g) preventing illnesses, or (h) improving sexual function. The wide range of medicinal uses recorded for these practices, which can be separated as either being specific (103 reports) or unspecific (88), are shown in Table 3. Determining the function of plants in depurative practices is less straightforward as, often, precise plant activities can not be Fig. 3. Tovomita aff. stylosa with a single stilt root (left), and Tovomita foldatsii showing multiple stilt roots (right). Both are the plants most employed in the strict depurative practices in Chazuta valley. J. Sanz-Biset, S. Cañigueral / Journal of Ethnopharmacology 145 (2013) 67–76 75 Table 3 Medicinal uses reported in the 191 depurative practices recorded in Chazuta valley (Peruvian Amazon). Specific medicinal uses recorded (103 reports) Unspecific medicinal uses recorded (88 reports) Rheumatism (40 reports) For hunting and fishing preparedness (11) Febrifuge (7), malaria (3) Broken bones (6), inguinal hernia (5) Cough (5), bronchitis (5) Vermifuge (5), stomach pains (2) Tobacco and cocaine addiction (2) Abscesses (2), leishmaniosis (2) Tumors (2) Urine infection (2), vaginal pains (1) Lumbago (1) Pulmonary disease (1) AIDS (1) Depurative tonic Cleansing tonic Tonic To augment work performance To enhance endurance (hacerse más bizarro) To increase weight carrying To extend cold resistance To sharpen the senses To lessen sluggishness (dejar de ser arragán) To prevent illnesses To improve sexual function directly associated. In some cases plants are considered to play an important role in depurative practices used against specific ailments, mainly diseases where pain, inflammation and infection are present. Indeed, many plants employed in strict depurative practices are known to harbour activities such as antinflammatory and antimicrobial (Sanz-Biset and Cañigueral, 2011). Nevertheless, the broadness of the use reports obtained is maintained in depurative practices—either these being mild or strict, either these using one plant remedy or another. Thus, once the depurative effect is induced, Chazutians expect this wide array of medicinal effects from it. A similar pattern applies for the plants employed in these practices, where the depuration considered to produce the broad spectrum of medicinal effects is fundamentally triggered by the stimulation of emesis. The broadness of the use reports, the high number of unspecific uses reported and the fact that the induction of emesis is a common factor for the plants used suggest the involvement of adaptive stress responses in depurative practices and also support considering plants as medicinal stressors, that is, as inducers of beneficial levels of stress. Bearing in mind plants as medicinal stressors can lead to targeting different bioactivities. In addition, a quick look at the plants mostly used in Chazuta’s depurative practices clearly indicates the likely presence of CNS activity, especially in those plants belonging to the Apocynaceae, Clusiaceae, Loganiaceae, Malpighiaceae, Solanaceae and Rubiaceae families. Species of those botanical families were involved in 127 depurative practices reports (66% of all). It is clear that CNS activity could take part into the whole activation of the stress system. Also, a psychological aspect may contribute to the use of such drastic practices that depurations are. When the body is put under such pressure, whether through vomiting or starving, the state of the mind may be expected to follow a particular pattern where CNS plant activity may have its role. 4. Conclusions Overall, 191 depurative practices were reported in Chazuta using 114 different plant species which were recorded and identified. These practices can be classified as mild (93 reports) or strict (98) depending on how severe in restrictions and prolonged in time they are. By inducing moderate stress through emesis and calorie restriction and within safe levels, depurative practices in Chazuta could produce adaptive responses that would protect against the detrimental consequences of chronic stress and stress-related diseases. This hypothesis could help to understand the diversity of the medicinal uses that we recorded in the field, either specific (103 reports) or unspecific (88). The experimental data shown in this paper supports considering plant remedies used in these practices in Chazuta as ‘‘medicinal stressors’’ as through vomiting the necessary neuroendocrine stress activation would be produced. In addition, CNS activity and other bioactivities that plants may harbour could converge with the whole stress reactivity process. Acknowledgements To the people of Chazuta that were happy to share with us their knowledge; and to José Campos de la Cruz, Mirbel Epiquien Rivera and the other botanists who helped in the plant determination. Appendix A. Supporting information Supplementary data associated with this article can be found in the online version at http://dx.doi.org/10.1016/j.jep.2012.09.053. References Baer, G., 1979. Religión y chamanismo de los Matsigenka (Este Peruano). Amazonia Peruana 2, 101–138. Cárdenas-Timoteo, C., 1989. Los Unaya y su mundo, Editorial CAAAP, Peru. Chaumeil, J.P., 1979. Nikamwo. 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