Traditional Medicinal Plants of Sri Lanka and Their Derivatives of Benefit to the Nervous System

Abstract

Nervous system disorders are increasing in global prevalence. The prevention and treatment of nervous system disorders by modern medicines are insufficient, facilitating the rapid growth and use of traditional medicines. Plant-derived herbal preparations are used for the well-being and treatment of nervous system disorders by a large proportion of the Sri Lankan population. This ethnopharmacology may be common to the Southeast Asian region, as in Ayurvedic treatments, or endemic to Sri Lanka. While some herbs of benefits to the nervous system are currently under scientific investigation (e.g., Centella asiatica, Bacopa monnieri, Curcuma longa, Withania somnifera), others are less well known (e.g., Celastrus paniculatus, Evolvulus alsinoides, Acorus calamus, Sphaeranthus indicus). Notably, many bioactive components beneficial to the nervous system have been described from “single-herb” preparations. Scientific data on the mechanisms of action of these phytochemicals from herbal plants are available. Further poly-herbal preparations are frequently used in the treatment of neurological disorders or for enhancing nervous system function. The efficacy of these treatments has been demonstrated over the centuries. The compositions of these preparations are discussed in terms of concurrent and synergistic actions, the negation of toxicity, and other features as sometimes described in their formulation. However, many of these preparations require scientific elucidation, where scientific data to determining active ingredients and mechanisms of action are needed. This, together with the growing interest in preventive health, has led to an interest in the health benefits of foods and traditional treatments of nervous system disorders.