An update on Ayurvedic herb Convolvulus pluricaulis Choisy

Convolvulus pluricaulis Choisy(C.pluricaulis)is a perennial herb that seems like morning glory.All parts of the herb are known to possess therapeutic benefits.The plant is used locally in Indian and Chinese medicine to cure various diseases.It is used in Ayurvedic formulation for chronic cough,sleeplessness,epilepsy,hallucinations,anxiety etc.Based on the comprehensive review of plant profile,pharmacognosy,phylochemistry,pharmacological and toxicological data on the C.pluricaulis,there will be more opportunities for the future research and development on the herb C.pluricaulis.Information on the C.pluricaulis was collected via electronic search(using Pub Med,SciFinder,Google Scholar and Web of Science)and library search for articles published in peer-reviewed journals.Furthermore,information also was obtained from some local books on ethnopharmacology.This paper covers the literature,primarily pharmacological,from 1985 to the end of 2012.The C.pluricaulis is an important indigenous medicine,which has a long medicinal application for liver disease,epileptic disease,microbial disease,cytotoxic and viral diseases,central nervous system(CNS)disease in Ayurvedic medicine,traditional Chinese medicine and other indigenous medical systems.The isolated metabolites and crude extract have exhibited a wide of in vitro and in vivo pharmacological effect,including CNS depression,anxiolytic,tranquillizing,antidepressant,antistress,neurodegenerative,antiamnesic,antioxidant,hypolipidemic,immunomodulatory,analgesic,antifungal,antibacterial,antidiabetic,antiulcer,anticatatonic,and cardiovascular activity.A chemical study of this plant was then initiated,which led to the isolation of carbohydrats,proteins,alkaloids,fatty acids,steroids,coumarins.flavanoids,and glycosides as active chemicals that bring about its biological effects.A scries of pharmacognostical studies of this plant show that it is a herb,its stem and leaves are hairy,more over it has two types of stomata,anisocytic and paracytic.A herb,C.pluricaulis has emerged as a good source of the traditional medicine for the treatment of liver disease,epileptic disease,microbial disease,cytotoxic and viral diseases,and CNS disease.Pharmacological results have validated the use of this species in traditional medicine.All the parts of the herb are known to possess therapeutic benefits.Expansion of research materials would provide more opportunities for the discovery of new bioactive principles from C.pluricaulis.

Novel insights on acetylcholinesterase inhibition by Convolvulus pluricaulis,scopolamine and their combination in zebrafish

Acetylcholinesterase(AChE)inhibitors increase the retention of acetylcholine(ACh)in synapses.Although they allevi-ate cognitive deficits in Alzheimer’s disease,their limited benefits warrant investigations of plant extracts with similar properties.We studied the anti-AChE activity of Convolvulus pluricaulis(CP)in a zebrafish model of cognitive impair-ment induced by scopolamine(SCOP).CP is a perennial herb with anti-amnesiac and anxiolytic properties.It contains alkaloid,anthocyanin,coumarin,flavonoid,phytosterol and triterpenoid components.Isoxazole(ISOX)was used as a positive control for AChE inhibition.CP-treated 168 hpf larvae showed a similar pattern of AChE inhibition(in the myelencephalon and somites)as that of ISOX-treated larvae.CP was superior to ISOX as evidenced by the retention of avoidance response behavior in adult zebrafish.Molecular docking studies indicated that ISOX binds Ser203 of the catalytic triad on the human AChE.The active components of CP-scopoletin and kaempferol-were bound by His447 of the catalytic triad,the anionic subsite of the catalytic center,and the peripheral anionic site.This suggested the ability of CP to mediate both competitive and non-competitive modes of inhibition.Surprisingly,SCOP showed AChE inhibition in larvae,possibly mediated via the choline-binding sites.CP+SCOP induced a concentration-dependent increase in AChE inhibition and ACh depletion.Abnormal motor responses were observed with ISOX,CP,ISOX+SCOP,and CP+SCOP,indicative of undesirable effects on the peripheral cholinergic system.Our study proposes the examination of CP,SCOP,and CP+SCOP as potential AChE inhibitors for their ability to modulate cognitive deficits.