Traditional Chinese Medicine in Treatment of Metabolic
Sophora flavescens Ait.: Traditional usage, phytochemistry
Traditional herbal medicine
Traditional herbal medicine has been used since ancient time in many parts of the world where access to formal and modern healthcare is limited. Nepal is not exempt and in mid-hills, mountainous and rural areas of the country where access and services are limited, herbal medicine is the basis of treatment of most illness through traditional knowledge. It is estimated that approximately 90% of the Nepalese people reside in rural areas where access to government health care facilities is lacking . These people rely predominantly on traditional herbal medicine. Traditional medicine is made available via ancient, natural health care practices such as tribal lore, home herbal remedy, and the Baidhya, Ayurveda and Amchi (traditional healing system of Tibet and mountain areas of Nepal) systems. The former one is innate to the tribal group (i.e. Raute in study area) . Home herbal remedy and the Baidhya system are indigenous to far-west Nepal [14,15] and are partly influenced by the Ayurveda . Extant of home herbal remedy in far-west Nepal is also due to relatively homogenous resource users and less encroachment from immigrants. Home herbal remedy and Baidhya system, yet transformations of the Ayurveda, are well established and practiced in the study area. The Amchi system is widely accepted and practiced throughout high altitude areas of Nepal  and is important in Darchula district, albeit with some modifications .
As communicated by Kunwar et al. , the knowledge base for traditional herbal medicine stems from spirituality, customs, livelihood strategies and available nearby resources. Medicinal herbs are main ingredients of traditional herbal medicine, and the traditional herbal medicine is considered as the main lifeline , the first choice , fewer side-effects, better patience tolerance, relatively less expense, and cultural acceptance and long history of use, in comparison to western medicine. Thus, the traditional herbal medicine has not only survived but also thrived in the trans-cultural environment with its intermixture of ethnic traditions and beliefs. Most of the time, this knowledge is passed on orally and therefore is endangered. Particularly the Amchi knowledge is passed down through dedicated apprenticeships under the tutelage of senior Amchi . Although traditional herbal medicine is effective in treatment of various ailments with considering ritual and socio-cultural customs , very often the medicine is used indigenously with indifference to the scientific knowledge and their possible side effects were overlooked. The dearth of reports of adverse effects and interactions probably reflect a combination of under-reporting and the benign nature of most herbs used . Therefore, the traditional herbal medicine deserves a great scope of research in the light of modern science.
The present assessment showed that traditional herbal medicine has flourished in rural areas where modern medicine is parsimoniously accessed as a result of the high cost and long travel time to health center. Moreover inadequate modern medical resources/facilities and government subsidies also made traditional herbal medicine pertinent in Nepal. It is estimated that there is one physician for every 20,000 people whereas there is more than one healer for every 100 people in Nepal [41,42]. Herbal medicine prescribed by healers is either preparation based on single plant part or a combination of several plant parts. However, we dealt only the primary one for further discussion in the present study. Many of the plants most often used in study area to treat ailments are also commonly used all over Nepal. Particularly the ethnic groups and scheduled caste are the major stakeholders of the traditional herbal medicine , so, traditional medicine is still the mainstay of health care in the rural areas of Nepal where the majorities of the denizens are from ethnic groups and scheduled castes.
The results obtained support prior observations, pharmacology and Ayurvedic uses concerning the following species: the crude extracts of Acacia catechu for cold and cough, Aconitum spicatum as analgesic, Aesculus indica for joint pain, Andrographis paniculata for fever, Anisomeles indica for urinary affections, Azadirachta indica for fever, Euphorbia hirta for asthma, Taxus wallichiana for tumor control, and Tinospora sinensis for diabetes. This probably explains the use of these plants by indigenous people against a number of infections as transcend from transcultural environment with following home herbal remedy, Ayurveda and Baidhya systems. It is known that the families Rutaceae and Meliaceae are among the richest and most diverse sources of secondary metabolites among the angiosperms , and the species of Meliaceae are known to have intense antimalarial characters due to highly oxygenated terpenoids . Use of leaves of Azadirachta indica (Meliaceae) as antipyretic is widely used in study area (Table ) and throughout Nepal  was substantiated by the nimbidin flavonoids [,]. Oleic acid and gedunin of A. indica are also reported to be an in vitro antimalarial [-]. Other species contributed as antipyretic in home herbal remedy in study area were Andrographis paniculata (Acanthaceae), Aconitum spicatum (Ranunculaceae) and Osmanthes fragrans (Oleaceae).
Andrographolide and neoandrographolide from Andrographis paniculata own anti-inflammatory activity [52,]. Its diterpene exhibits antioxidant and hepato-protective properties [54-57]. Immunostimulant , antibacterial , analgesic  and antiprotozoal  characteristics of A. paniculata extract have also been demonstrated. These values probably explain the use of A. paniculata by the indigenous people against a number of infections and fever. Crude root extract of Podophyllum hexandrum (Berberidaceae) was used as hepato-protective, despite the hepatotoxic character reported due to its lignans . Podophyllotoxin has manifested antimitotic activity and capability of inhibiting DNA, RNA and protein synthesis . There were seven species in study area exhibiting hepato-protective effects. Among them, six were pharmacology based and three were folkloric. Plant extracts of P. hexandrum and Andrographis paniculata showed hepato-protective characters consistent with the folk use and pharmacology.
Alkaloids are most common in flowering plants, especially in Fabaceae, Ranunculaceae and Solanaceae . Some alkaloids (aconitine, anisodamine, berberine, charantine, leurosine) show antidiabetic effects . Berberine of Tinospora sinensis (Menispermaceae) is antidiabetic [-], but higher doses may be antagonistic , which strongly support the folkloric use of the plant extract. According to Marles and Farnsworth , there are about 1,000 species of plants that can act as an antidiabetic and approximately 80% of these are used in folk herbal medicine. Antidiabetic reports of Azadirachta indica, Carum carvi, Tinospora sinensis and Vitex negundo stated in the present communication were pharmacologically rationale and that of A. indica and T. sinensis was folk-based.
Euphorbiaceae species are generally characterized by milky latex , and sticky saps are co-carcinogenic, and can cause severe skin irritation and are toxic to livestock and humans . They are rich in active compounds including terpenoids, alkaloids, phenolics and fatty acids, having ethnopharmaceutical uses . Sapium insigne (Euphorbiaceae) is skin irritant, and commonly used as fish poison in study area and throughout Nepal . Both the water and methanol extracts of Euphorbia hirta (Euphorbiaceae) are antibacterial [74,] and effective as expectorant [76,77] and broncho-dilator , which is consistent with the folkloric use in treatment of respiratory complaints.
Pharmacologically, curcumin of Curcuma species (Zingiberaceae) acts as an anti-inflammatory [-80], antibacterial , antiviral , antifungal , antitumor [,], antispasmodic , and hepato-protective . The oxygen radical scavenging activity of curcumin has been implicated in its anti-inflammatory effects [,89] thus curcumin may prove useful as a drug for arthritis, cancer, HIV [-] and high blood pressure . Wide range of pharmacological reports including antibacterial and antiviral complements the folk use to treat paralysis. Rhizome extract of the plant was widely used for skin diseases (bruises, injuries, etc.) in west Nepal  and in the Ayurveda .
The folk use of Acacia catechu (Fabaceae) wood tea as an expectorant fairly corroborated the pharmacological properties because the tannin and cyanidanol [94,95] of the plant impart astringent activity which helps to recuperate diarrhea. Tannins are also known as antimicrobial  and triterpenoids are beneficial for inflammation and cancer . The hepato-protective and hypoglycemic properties of A. catechu could be attributed to the quercetin  and epicatechin  respectively. Leaf extracts of Taxus wallichiana (Taxaceae) inhibit pregnancy in rats , vitiate blood disorders  and control tumor growth . In the study area, Taxus leaf juice is used for treatment of cancer and bronchitis.
Lectins of Cannabis sativa (Cannabaceae) possess haema-gluttinating properties  which corroborate the indigenous use of the leaf extract to control bleeding. Crude leaf extract of Vitex negundo (Verbenaceae) is recommended as antitussive and anti-asthma , antibacterial , antifungal , hypoglycemic , anti-cancer , acne control , inhibitor of edema [108,109] to tracheal contraction . However, it did not corroborate the folk use for stomachache but was partially complemented by earlier observations [30,111]. The unlike uses of the species after thorough scrutiny, under different medical systems and comparisons pose more research scopes. Several instances are rational behind a certain function of a phytomolecule sometimes inconsistent to the pharmacology and ethnopharmacology. Moreover, while advocating herbal medicine as alternative therapy, toxicity of plants should be borne in mind.
Lichens and their metabolites have manifold biological activity: antiviral, antibiotic , antitumor, allergenic, plant growth inhibitory, antiherbivore, ecological roles and enzyme inhibitory [,114]. Usnic acid and vulpunic acid (produced by mycobiont) of lichens are mitotic regulators  and own antibiotic properties . Parmelia sulcata lichen manifests antibacterial and antifungal activities [,118]. Use of Parmelia species to treat warts  is analogous to its folk use. Folk use of wood tea of Quercus lanata (Fagaceae) as a laxative may verify the actions of tannin. Tannins reveal activities against central nervous system disorders  and inflammation [,]. Further pharmacological evaluation of the extracts of those species which reveal weak pharmacological validities are needed before they can be used as therapeutic potentials.
The compounds which contribute to the antioxidative properties are polyphenols , vitamin C , β carotene , anthocyanins , and flavonoids . Ellagic acid of Fragaria nubicola (Rosaceae) is also responsible for antioxidant activity . Antioxidants are associated with reduced risk of cancer and cardiovascular diseases  and many other ailments . Antimicrobial and anti-inflammatory properties of Fragaria fruit extracts [101,131] are consistent with the folkloric use as remedy for skin diseases and wounds. The usage of root powder of Potentilla fulgens (Rosaceae) as a dentifrice is common in the study area and throughout Nepal [,133] and it is in accord to the Ayurvedic uses. However, the usage is yet to be verified pharmacologically.
Wogonin of Scutellaria discolor (Lamiaceae) is considered as a most potent antiviral  and anxiolytic  compound. Plant root extract is also useful for rheumatism . Whole plant and leaf paste is useful for cuts & wounds, which probably rationalize the activities of wogonin. Linalool also possesses an anxiolytic effect , and this effect probably substantiates the folk uses of Skimmia anquetilia (Rutaceae) leaves as medicine for headache and freshness. Linalool is the main constituent of Skimmia root. The indigenous uses of six species Arisaema flavum, Ficus religiosa, Rhododendron campanulatum (Figure ), Smilax aspera, Solena heterophylla and Sterculia villosa repudiated to any of the comparables, since these uses were additional to the Nepalese ethnomedicinal vault and these addition demands further research.
Rhododendron campanulatum D.Don (Chimal): Flowers are used in body ache and throat pain.
Aconitum spicatum (Ranunculaceae), taken alone is poisonous, so it is never used alone by the local communities. A paste made from its roots is applied as antipyretic and analgesic after mixing with Terminalia chebula (Combretaceae). Folk use of root extract of A. spicatum as an analgesic is consistent to the anti-inflammatory activity of caffeic acid found in the plant extract . About 80% of plant alkaloids possesses anti-inflammatory properties and among them isoquinoline (berbamine, berberine, cepharanthine and tetrandine) was the most active [,140]). Diterpenoid alkaloids, commonly isolated from the plants of Ranunculaceae family, are commonly found to have antimicrobial properties . Folk uses as antipyretic and analgesic of A. spicatum root extract are validated by the in vitro antimicrobial properties. In some cases, multi-component therapy has been practiced and considered as effective as Kareru et al.  observed in Kenya, but the present assessment considered only the primary one to discuss. We believe that the associate plants must also be considered as excellent candidates for future studies to determine the mechanisms of their activity, as well as for the isolation and identification of active constituents [143,]. Thus, traditional herbal medicine renders primary health care needs of two thirds of the rural population of the Nepalese, represents a largely unexplored source for potential development of new drugs [145,].