title: Verbascoside isolated from Tectona grandis mediates gastric protection in rats via inhibiting proton pump activity.
abstract: Evidences have suggested that Tectona grandis (TG) attenuates gastric mucosal injury; however its mechanism has not yet been established. The aim of present study was to evaluate the gastroprotective mechanism of ethanolic extract of TG (E-EtOH), butanolic fraction (Fr-Bu) and to identify its active constituents. Anti-ulcer activities were evaluated against cold restraint (CRU) and pyloric ligation (PL) induced gastric ulcer models and further confirmed through H(+) K(+)-ATPase inhibitory activity. Cytoprotective activity was evaluated in alcohol (AL) induced gastric ulcer model and further through PGE(2) level. E-EtOH and Fr-Bu attenuated ulcer formation in CRU. Moreover E-EtOH and Fr-Bu displayed potent anti-secretory activity as evident through reduced free acidity and pepsin activity in PL, confirmed further by in vitro inhibition of H(+) K(+)-ATPase activity. In addition cytoprotective potential of E-EtOH and Fr-Bu were apparent with protection in AL model, increased PGE(2) content and enhanced mucin level in PL. Phytochemical investigations of Fr-Bu yielded terpenoides and a phenolic glycoside, verbascoside. The anti-secretory mechanism of verbascoside mediated apparently through inhibition of H(+) K(+)-ATPase with corresponding decrease in plasma gastrin level, is novel to our finding. Gastroprotection elicited by TG might be through proton pump inhibition and consequent augmentation of the defensive mechanism.
authors.affiliation: Division of Pharmacology, Central Drug Research Institute, CSIR, Lucknow-226001, Uttar Pradesh, India. singh_neetu2000@rediffmail.com
authors.forename: Neetu
authors.initials: N
authors.lastname: Singh
authors.forename: Nivedita
authors.initials: N
authors.lastname: Shukla
authors.forename: Pratibha
authors.initials: P
authors.lastname: Singh
authors.forename: Rolee
authors.initials: R
authors.lastname: Sharma
authors.forename: S M
authors.initials: SM
authors.lastname: Rajendran
authors.forename: Rakesh
authors.initials: R
authors.lastname: Maurya
authors.forename: Gautam
authors.initials: G
authors.lastname: Palit
mesh_terms: D000818:Animals; D000897:Anti-Ulcer Agents / Q000302:isolation & purification / Q000494:pharmacology* / Q000627:therapeutic use; D003080:Cold Temperature; D015232:Dinoprostone / Q000378:metabolism; D004195:Disease Models, Animal; D005260:Female; D005744:Gastric Acid / Q000378:metabolism; D005753:Gastric Mucosa / Q000378:metabolism; D005755:Gastrins / Q000097:blood; D005960:Glucosides / Q000032:analysis / Q000494:pharmacology* / Q000627:therapeutic use; D008297:Male; D009077:Mucins / Q000378:metabolism; D010434:Pepsin A / Q000037:antagonists & inhibitors; D010636:Phenols / Q000032:analysis / Q000494:pharmacology* / Q000627:therapeutic use; D008517:Phytotherapy; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology* / Q000627:therapeutic use; D018515:Plant Leaves; D054328:Proton Pump Inhibitors; D051381:Rats; D017207:Rats, Sprague-Dawley; D000254:Sodium-Potassium-Exchanging ATPase / Q000037:antagonists & inhibitors*; D013270:Stomach / Q000187:drug effects; D013276:Stomach Ulcer / Q000188:drug therapy* / Q000378:metabolism; D029648:Verbenaceae / Q000737:chemistry*; D059808:Polyphenols
chemical_list: D000897:Anti-Ulcer Agents; D015232:Dinoprostone; D005755:Gastrins; D005960:Glucosides; D009077:Mucins; D010434:Pepsin A; D010636:Phenols; D010936:Plant Extracts; D054328:Proton Pump Inhibitors; D000254:Sodium-Potassium-Exchanging ATPase; C058956:acteoside; D059808:Polyphenols