Review on ethnomedicinal, phytochemical and pharmacological evidence of Himalayan anticancer plants.

BACKGROUND

Himalayan plants have 6500 years old history of being using as traditional medicines. Inhabitants of the region use indigenous knowledge for the preparation of various herbal recipes in order to treat different kinds of cancer. The aim of this review is to provide ethnopharmacological, phytochemical and toxicological overview of Himalayan medicinal plants having anticancer potential. This will provide a baseline for the discovery of new anticancer drugs.

METHODS

In total, 155 articles (mostly published) were reviewed by using online search engines like PubMed, Scopus, Google Scholar, Web of Science, and floras of different Himalayan countries.

RESULTS

Sixty four anticancer medicinal plants were documented belonging to 59 genera and 37 families. Majority of 42 plants were reported from India followed by 17 from Pakistan. Traditional healers in the region mostly prepare ethnomedicinal recipes from leaves (32% plants) and roots (30% plants) in the form of decoction. Thirty plants had reported anticancer related pharmacological and phytochemical activities. Of these, 27 plants were tested in-vitro on cellular models while 16 plants for in-vivo activities. Methanolic, ethanolic and ethylacetate extracts of plants have shown excellent cytotoxic activities against breast, stomach and blood cancers' cell lines. Total 14 active secondary metabolites including phenolic compounds, glycosides, terpenoids, lignans and alkynes from the studied plants were reported active against different cancer cell lines. Plants such as Bergenia ciliata, Argemone mexicana, Capsella bursa-pastoris and Centella asiatica had toxic effects on the living systems at higher doses when studied in-vivo.

CONCLUSIONS

Certain Himalayan medicinal plants present therapeutic properties against different types of cancer. However, not all of the plants have been fully analysed for in vitro, in vivo and toxicological activities, and isolation of secondary metabolites. Further ethnomedicinal studies would help in identifying potential medicinal plant species in the region to be analysed for detailed anticancer activities.