In-vitro evaluation of anti-urolithiatic activity of leaves of alstonia scholaris

Background: Urolithiasis has become a global problem with increased prevalence over last few years. Renal calculi formed usually comprises of calcium oxalate as a major constituent. Conventional treatments include use of vasodilators in early stage of urolithiasis, whereas, staghorn calculi requires Extracorporeal Shockwave Lithotripsy (ESWL) intervention which carries risk of renal injury and recurrence. They are also expensive, time bound and associated with side effects. Literature reports medicinal plants rich with multi-functional bio-active constituents, possessing lithotriptic potential which needs to be scientifically explored. Objective: Pentacyclic triterpenoids viz. lupeol, ursolic acid and betulin are reported in literature for their anti-urolithiatic effect. As the plant Alstonia scholaris (L.) R. Br. Apocynaceae is rich with these phyto-constituents, this study was conducted with the objective to find out in-vitro lithotriptic activity of four extracts of leaves of Alstonia scholaris, in comparison with standard poly herbal preparation Cystone (Cys). Method:-Leaves of Alstonia scholaris were extracted with Methanol (MeAS), Chloroform (ChAS), Ethanol (EtAS) and Hydro-ethanol (HeAS) solvents using soxhlet apparatus. Preliminary phytochemical screening of the extracts was performed to identify presence of triterpenoids; which was further confirmed by HPTLC. In-vitro lithotriptic effect of four extracts was evaluated by incubating each extract (50,100,200,400 and 800mg) at different time intervals (8, 18 and 24 hours) with calcium oxalate crystals (10mg) in semi-permeable membrane isolated from chicken eggs. Result:-Class of compound determination by HPTLC confirmed presence of pentacyclic triterpenoids in all four extracts with the highest content in EtAS. The order of extent of dissolution of calcium oxalate crystals observed was EtAS>ChAS>HeAS>MeAS. Conclusion:-Maximum lithotriptic activity of leaves of Alstonia scholaris was observed with extract EtAS which is comparable with standard Cystone. Thus, anti-urolithiatic effect exhibited by leaves of Alstonia scholaris can be attributed to the presence of pentacyclic triterpenoids detected in the plant.