The concept of ^Musa-pelo and the medicinal use of shrubby legumes (Fabaceae) in Lesotho

In the Kingdom of Lesotho, 20 plant species are commonly known as 'Miisa-pelo. The term literally means ‘the one who brings back or tums around the heart’. 'Musa-pelo is traditionally used as a sedative and is given as a first aid treatment to bereaved people who are under severe psychological duress or stress. Of the 20 species known as 'Musa-pelo, 17 belong to nine genera of the Fabaceae (Argyrolobium, Crotalaria, Indigofera, Lessertia, Lotononis, Melolobium, Sutherlandia, Tephrosia and Trifolium). The three remaining species namely Cleome monophylla, Heliophila carnosa and Cysticapnos pruinosa, belong to the families Capparaceae, Brassicaceae and Fumariaceae, respectively. In this paper, the concept of 'Musa-pelo in traditional medicine is explored.


INTRODUCTION
The concept o f 'Musa-pelo is an important part of tra ditional medicine in Lesotho. 'Musa-pelo and its cultural significance is described and explained here for the first time in a scientific context. Watt & Breyer-Brandwijk (1962) did not discuss 'Musa-pelo in their comprehen sive review of medicinal plants of southern and eastern Africa. The aim of this paper is to present and discuss the identity and uses of 20 plant species that are known as 'Musa-pelo or that have been reported in the literature as 'Musa-pelo.

METHODS
The study was based mainly on a literature survey and observations made by the first author on traditional practices at home and in the community; the first author has also used some of these remedies. Some traditional healers were consulted with regards to the use of Cleome monophylla as 'Musa-pelo-the plant was shown to them in the field.

DISCUSSION
The concept o / 'Musa-pelo 'Musa-pelo is used to treat fits, circulation problems, stress-related ailments and chronic illnesses (Maliehe 1997), As a traditional healer, Eric Maliehe (pers. comm.) pointed out: 'for ages and ages the Basotho have been using 'Musa-pelo for trauma because trauma is considered to affect the heart first'. The term 'Musa-pelo literally means 'one who brings back or tums around the heart' and according to him, it means 'bringing back health to the heart'. It is a term given to several plant species traditionally used to cure or ease a 'sore heart' or dropsy o f the heart (Phillips 1917;Jacot Guillarmod 1971). In the first author's own experience, 'Musa-pelo is administered as a sedative to bereaved people who are under severe psychological duress or stress. It is given to recently widowed women for spasms and heart disease. Most of the traditional uses point to possible sedative and/or stress-relieving activity for the plants involved.

Plants known to be used as 'Musa-pelo
Detailed information on the Sesotho names and the traditional uses (where known) of the 20 species known to be 'Musa-pelo plants are given in Appendix 1. Authorities for the scientific names are included in Appendix 1 and will not be given elsewhere. In all, 20 plant species, including 17 belonging to the fam ily Fabaceae are called 'Musa-pelo. These include two species of Argyrolobium, one o f Crotalaria, four of Indigofera, two of Lessertia and one o f Sutherlandia. Three other species Cleome monophylla (Capparaceae), Cysticapnos pruinosa (Fumariaceae) and Heliophila car nosa (Brassicaceae), have also been listed as 'Musa-pelo. Heliophila carnosa is used for auscultation (Phillips 1917); and is also known in Sesotho as Semameloana, meaning 'the small one who listens'. Cysticapnos prui nosa is used as a 'charm to comfort and drug the sorrow ing' (Jacot Guillarmod 1971). Phillips (1971) recorded 'Musa-pelo as a Sesotho name for Cleome monophylla, but did not provide any details of its usage. After consul tation with several traditional healers in Lesotho regard ing the use of C. monophylla, none of them could con firm that it is used as 'Musa-pelo.
To distinguish between the 20 species with one com mon name, variations to the name are applied either to describe a striking feature o f the plants, their size or their habitat. For example, Melolobium alpinum is 'Musapelo-o-moholo-oa-thaba (the big mountain 'Musa-pelo) because it is indeed an alpine species. To differentiate Crotalaria distans, flower colour is added to the name, i.e. 'Musa-pelo-o-mosehlanyana (the yellowish 'Musapelo). Lotononis sericophylla is characterized by whitish hairs and is known as 'Musa-pelo-o-mosoeu (the white 'Musa-pelo).
Members of the Fabaceae are well known as rich sources of nitrogen compounds. Some of the species in Appendix I have been investigated (summarized in Harbome 1994): Argyrolobium lotoides and Melolobium alpinum contain quinolizidine alkaloids (anagyrine, cyti sine, leontidine and camoensine), Lotononis sericophylla is a source of pyrrolizidine alkaloids (integerrimine and senecionine), Crotalaha distam has amino acids (2,4diaminobutanoid acid and N-y-glutamyltyrosine), and Thfolium contains flavonoids (maackiain, medicarpin and vestiol). O f special interest is the closely related Sutherlandia and Lessertia, both of which contain high levels of free amino acids and canavanine (a non-protein amino acid) in the leaves (Van Wyk & Wink 2004).

Possible mode o f action o / 'Musa-pelo
Sedatives are drugs which depress the central nervous system. Many plants, including those of 'Musa-pelo, are also used traditionally as sedatives. The traditional use of Sutherlandia species to relieve anxiety and stress is believed to be due to the presence of the amino acid gamma-aminobutyric acid (GABA), a known inhibi tory neurotransmitter with mood-elevating properties (Van Wyk & Gericke 2000). It is interesting to note that Smith & Myburgh (2004) have presented evidence that Sutherlandia alters the corticosterone response in stressed rats.
Adaptogens are described as agents or biological substances (of plant origin) that help to increase the body's resistance to stress, whether physical, chemi cal or biological (Schulz et al. 2001). For a plant to be adaptogenic, it 'must be innocuous and cause minimal disorders in the physiological functions of an organism, it must have nonspecific action, and it usually has a nor malizing action irrespective of the direction o f the patho logical state' (Brekhman & Dardymov 1969). Some very well-known adaptogenic plants include Panax ginseng (Asian ginseng), P. quinuefolium (American ginseng), Eleutherococcus senticosus (Siberian ginseng), Rhodiola rosea (roseroot) and Withania somnifera (often called Indian ginseng) (Van Wyk & Wink 2004).
Immune stimulants are substances that help increase the activity of the body's immune system but without any antigenic action against specific pathogens, whether viral or bacterial (Schulz et al. 2001). They are therefore similar to adaptogens in that their action is nonspecific and could be multifocal. Two well-known immune stimu lant herbs are Echinacea spp. (coneflower) and Viscum album (mistletoe).
Digestive bitters (amara) are tonic herbs with a bit ter taste thought to stimulate the taste buds and promote (as a reflex via the vagus nerve) the secretion of saliva, gastric juices and bile (Van Wyk & Wink 2004). The bit terness can be due to a number of chemical constituents including volatile oils, alkaloids and sesquiterpene lac tones. Surprisingly, bitters also act on the cardiovascu lar system, decreasing the heart rate and cardiac stroke volume (Schulz et al. 2001). Some commonly used bitter herbs include Gentiana lutea (gentian), which occurs in mountains o f central and southern Europe, Centaurium erythraea (century), primarily distributed in the Mediterranean and Artemisia absinthium (worm wood), native to temperate regions of Europe, Asia and northern Africa.

CONCLUSIONS
It appears to be no coincidence that of the 20 plants used as 'Musa-pelo, 17 plant species are from the Fabaceae, a family known for its rich diversity of nitro gen compounds (Harbome 1994)-alkaloids, phenolic amines, amino acids, nonprotein amino acids and other constituents known to act on the central nervous system. The chemical composition of most 'Musa-pelo plants and their pharmacological activities (such as possible corticomimetic and neuromodulatory effects), are not yet known, and this opens up a new area of investigation. It should be pointed out, however, that some plants belong ing to certain listed genera (Argyrolobium, Crotalaria, Indigofera and Lotononis) have been reported to have indications o f toxic potential (Hutchings et al. 1996), therefore, it is advisable that these remedies should not be taken without proper knowledge of required dosages. It is possible that 'Musa-pelo plants have undiscovered compounds inducing adaptogenic, bitter (amarum) or neuroreceptor responses which are, individually or col lectively, responsible for the sedative or mood-enhancing effects reported for these plants. Altogether there are 20 species listed as 'Musa-pelo plants, however there is no evidence that Cleome monophylla is used as 'Musa-pelo and should perhaps be excluded from the list.

ACKNOWLEDGEMENT
The University of Johannesburg is thanked for finan cial assistance.