Enquête ethnobotanique des plantes médicinales utilisées pour traiter l’ictère dans le district administratif de Labé (République de Guinée)

Introduction

Les maladies du foie sont une cause importante de morbidité et de mortalité dans le monde. L’ictère ou jaunisse est une coloration jaune de la peau, de la sclère et des muqueuses causée par la bilirubine. C’est une manifestation courante de la maladie hépatobiliaire (Abbas et al. 2016 ; Winger et Michelfelder, 2011). C’est l’une des affections les plus courantes qui touchent les hommes de tous âges. En médecine conventionnelle, l’ictère n’est pas considéré comme une maladie mais comme un symptôme visible d’une maladie hépatique, qui survient lorsque la quantité de bilirubine circulant dans le sang est élevée en raison d’un métabolisme anormal, entraînant une décoloration jaune des yeux et des téguments (Tewari et al. 2017).

La prévalence des pathologies liées à un dysfonctionnement hépatique entraînant l’ictéritérisme augmente dans le monde entier et est principalement causée par des virus (1,4 million de morts), le paludisme, des substances toxiques telles que le tétrachlorure de carbone, les médicaments et l’éthylisme alcoolique (Roy et al. 2014). L’Organisation mondiale de la santé (OMS) estime que 325 millions de personnes dans le monde vivront avec l’hépatite B et/ou C pour l’année 2023, dont 32 millions en Afrique. Pour la majorité, le dépistage et le traitement restent hors de portée (OMS 2023), conduisant à une cirrhose hépatique ou un cancer.

En Guinée, les personnes souffrent de grandes maladies hépatiques, et l’ictère représente 51,5 % des raisons des consultations hospitalières au service de gastro-entérologie-hépatologie (Diallo et al. 2023). De nombreux Guinéens utilisent encore des herbes traditionnelles pour traiter diverses maladies, y compris les maladies du foie, malgré la disponibilité de médicaments modernes, qui restent coûteux et inaccessibles, surtout en périurbain et en milieu rural.

Cependant, peu de données existent sur les plantes et leur utilisation par la population pour la gestion des Icterus. Cette étude vise à recueillir et documenter des informations sur la manière dont les guérisseurs traditionnels vivant à Labé diagnostiquent et traitent l’ictère.

2 Matériel et méthodes

3 Results

Thirty-seven (37) traditional healers were interviewed, and their demographic data are summarized in Table 1. The median age was 52, the minimum age of traditional healers was 35 and the maximum was 81; more than half of those interviewed 54.1 % were over 51 years, and the average age was 53 ± 12 years. Most traditional healers were Men (64.86 %; 24/37; p = 0.115). Inheritance (54.1 %; 20/37) was the primary source of knowledge acquisition.

Traditional healers in Fulani cited two types of icterus: “Rèmè” or “Danawel”. Yellow colouration of the eyes was described as “Rèmè”, and yellow colouration of the eye with a significant deterioration in the patient’s condition that could lead to death if not treated immediately as “Danawel”.

Traditional healers cited nine symptoms as symptoms of icterus (Table 2): “Guitè nètè” literally means yellow eyes (100 %), “Raouno bhandou” = pallor (29.7 %), “Angal wèlègol” = lack of appetite (27.0 %), “Horagol” = weight loss (13.5 %), “Moussou djiyè” = joint pain (8.1 %), “Woulou bhandou” = fever (8.1 %), chills (2.7 %), “Bhoutou redou” = swelling belly (16.2 %) and “Meto_houndouko” = dull mouth (5.4 %).

Traditional healers use medicinal plants to treat icterus, summarized in Tables 3 and 4. The leaves were the most used plant parts, followed by rhizomes and stem bark, with percentages of 69.4 % (25/37), 55.6 % (20/37), and 41.7 % (15/37), respectively (Table 3). The most commonly used preparation method was decoction, followed by maceration and grinding, with respective percentages of 83.3 % (30/37) and 58.3 % (21/37). Traditional practitioners used combinations of three plants (32.4 %) or more (29.7 %) to prepare their recipes.

Thirty-eight plant species belonging to 24 botanical families were used to treat icterius (Table 4). Despite Fabaceae (5 species) being the most represented family, Combretaceae (FUV=0.447), Bixaceae (FUV=0.342), and Apocynaceae (FUV=0.289) were the most influential families based on the FUV index. Cochlospermum tinctorium Perrier ex A.Rich (PUV=0.243) exhibited the highest value of the PUV index. Landolphia heudelotii ADC and Combretum micranthum G.Don had the same value (PUV=0.216), followed by Persea americana Mill (PUV=0.135) (Table 4).

4 Discussion

This study aimed to collect and document information on anti-icteric plants and their uses in Labé Prefecture from traditional healers.

Studies showed that men have a greater knowledge of plant species and their use, but it is no different for women (P=0.115). This could explain the male predominance, which is that men in African society are often the first to be involved in transmitting traditional knowledge. These results align with several ethnobotanical investigations in Guinea (Magassouba et al. 2007; Traore et al. 2013). The high number of ageing traditional healers could be explained by the rural exodus and the emigration of young people to industrialized countries for well-being (El Hachlafi et al. 2022; Mohamed S. Traore et al. 2022).

Inheritance was the most frequently cited means of acquiring knowledge, as shown by the results of some earlier studies carried out in Africa (M.S. Traore et al. 2013; Mohamed S. Traore et al. 2022; Benkhaira et al. 2021). It is advocated that knowledge of treatment of the disease acquired by inheritance and training must be documented for future generations.

Icterus was considered a disease and not a symptom in traditional medicine. Yellow eyes, pallor, lack of appetite, swelling belly, fever, and weight loss were the main ethno-medical signs of the disease. These symptoms could be similar to those of liver disease (Milner 2018; Langan and Goodbred, 2021; Ravi et al. 2022) but also of malaria, which is endemic in Guinea.

Their traditional remedies are mainly plant decoctions taken orally or used as a body lotion. However, some traditional healers suggest maceration to avoid destroying the recipe. These results are similar to those of Diatta et al.(2019) in Senegal, Sharma et al. (2012), and Deb et al. (2016) in India, who indicated that decoction might be the best preparation method for obtaining maximum active ingredients.

Most recipes comprised more than three plants. This could be explained by the fact that in traditional medicine, practitioners often use a combination of several plants, in all likelihood to obtain a synergistic action against several symptoms.

The most cited families were Fabaceae, Combretaceae, Hypericaceae, Bixaceae, and Apocynaceae. The dominance of these families can be explained by their extensive distribution in Guinea, where the ecological factors favour the vegetation of the species belonging to these families. Most nationwide surveys showed that Guinean healers widely use these families to treat many diseases (Camara et al. 2023; Haba et al. 2022; Goumou et al. 2022).

Leaves are the most plant parts used in recipes. This may be due to their easy harvesting and use by traditional practitioners. Using the leaves considers the need of traditional healers to protect their source of supply and the protection of biodiversity.

Several species’ anti-inflammatory, antimalarial, antioxidant, and antimicrobial activities have been described in the literature. Cochlospermum tinctorium was the plant most cited in our study for treating swollen belly. While this symptom is similar to hepatomegaly, the ethanolic extract of rhizomes showed hepatoprotective activity after CCl₄ administration in rats, and the chemical groups responsible for this activity are gallic and ellagic acids (Diallo et al., 1987). The in vitro antiplasmodial activity of 3-O-E-p-coumaroylalphitolic acid, betulinic acid, 3-tetradecanone, and 3-hexadecanone obtained from the plant roots has been previously demonstrated (Ballin et al. 2002; Ahmadu 2014). In Mali, a study by Sangaré showed a significant reduction in transaminases (GPT, GOT) with C tinctorium tea (Sangaré 2006). Cochlospermum planchonii, Carica papaya Mangifera indica, and Vernonia colorata were used by traditional practitioners to treat icterius. Previous studies showed these plant species have high antimalarial activities (Omoya 2016; Toyang et al. 2013; Atanu et al. 2021).

The main chemical constituents isolated from the ethanolic fractions of C tinctorium rhizomes are: 3-O-E-p-coumaroylalphitolic acid, cochloxanthin, dihydrocochloxanthin, alphitolic acid, 1-hydroxytetradecan-3-one in the dichloromethane, 3-bisabolen, 2tridecanone, 3-hexadecanone, 1-dodecanol, l-tetradecanol, 2-pentdecanone, 3-octadecanone, 1-hydroxy-3-hexadecanone, 1-nonadecanol, l-O-acetyl-3-hexadecanone, lhydroxy-3-oetadecanone (Diallo et al., 1987).

The traditional healers who cited Landolphia heudelotii assumed that its effectiveness was due to the orange colouration of its fruits, similar to the main symptom of icterus. Its aqueous and ethanolic extract showed promising antimalarial activity on Plasmodium NF 54 and K1 strains. These results could justify the use of this plant in the traditional treatment of icterus (Kipré et al. 2018). L. heudelotii leaves, Combretum paniculatum, and Combretum glutinosum, which are used for the management of icterus, were found to be highly active against P. falciparum in vitro, with CI₅₀ values of 1.3 and 3.6 μg/ml, 0.5 and 3.5 μg/ml, and 1.3 and 3.6 μg/ml, respectively (Baldé et al. 2020). Some traditional healers asserted that the complications of malaria led to the yellow colouration of the eye (M.S. Traore et al. 2013a).

Persea americana is cited in our survey to manage joint pain, weight loss, fever, and lack of appetite associated with icterus. These symptoms are like those of acute malaria. The study by Uzor et al. showed that Quercetin is the most prevalent flavonoid in the plant and is responsible for its antimalarial activity (Uzor et al. 2021). Oil from P americana seeds showed antioxidant potential thanks to its reducing power. This property is attributable to the flavonoids present in the seed. This shows avocado seeds are intended for nutrition and cosmetics and could have tremendous therapeutic potential. (Banji et al., 2019). Ethyl acetate extracts of P. americana stem bark and leaves showed similar anti-inflammatory activity to indomethacin, with inhibition percentages of 41.45 %, 25.78 %, and 21.08 %, respectively. The petroleum ether extract of the leaves also showed high anti-inflammatory activity, with an inhibition percentage of 38.55 %. The total stem extract, aqueous, and petroleum ether fractions of leaves showed analgesic activities close to those of acetylsalicylic acid (Mahmoud et al. 2021).

Combretum micranthum leaf extract has demonstrated intense antioxidant activity by scavenging free radicals (Kpemissi et al. 2019). A study on C micranthum herbal tea showed a significant transaminase drop (Haidara et al. 2016). Free radicals are known to be hemolytic (rupture of the red cell membrane through lipid peroxidation). Paleness is one of the symptoms cited by traditional healers in our survey, which often occurs when hemolysis is present. Also, previous studies showed the antiplasmodial activity of these species (Zofou et al., 2013; Baldé et al. 2020), which could justify the high FUV value of the Combretaceae family in our study.

Conclusion

This ethnobotanical study made it possible to highlight two types of icterus that traditional healers manage. The traditional remedies mainly focused on plant species, most of which have been described to possess antimalarial, hepatoprotective, anti-inflammatory, and(or) antimicrobial properties. However, traditional recipe standardization and bioassay-guided fractionation will be carried out to provide proof of efficacy, safety, and tolerance of these recipes or plants.