title: In vivo and in vitro anti-natriuretic activity of twigs fraction from Dorstenia picta: a possible mechanism.
abstract: The present study examine the in vivo effects of Dorstenia Picta (D. picta) on urinary volume and sodium excretion in streptozotocin-induced diabetic rats, and determine a possible mechanism by which the extract increased sodium transport in A6 cells monolayers. Administration of the plant extract at the dose of 150 mg/kg during two weeks decreased urinary volume and sodium excretion. In vitro study showed that, apical application of the plant extract at the dose of 100 µg/mL does not significantly increase sodium transport, whereas basolateral administration provoked a significant (P<0.05) increase of sodium transport in a concentration-dependent manner. The plant extract increases the sodium transport by 69.93% versus 55.41% for insulin and 78.44% for adenosine after 30 min. Preincubation of A6 cells monolayers with inhibitor of all adenosine receptors completely suppressed adenosine and plant extract stimulated sodium transport. Interesting is that, the A1 inhibitor receptor (DPCPX), at 100 nM completely abolished the effect of plant extract. The plant extract increased sodium transport by increase PI3-kinase activity and this effect is strongly inhibited by LY-294002. These data also suggest that, the twigs methanol fraction from Dorstenia picta increase sodium transport via PI 3-kinase pathway and requires A1 adenosine receptor.
authors.affiliation: Faculty of Science, Department of Animal Biology and Physiology, University of Yaounde, Cameroon. nguyeguimts@gmail.com
authors.forename: Ngueguim Tsofack
authors.initials: NT
authors.lastname: Florence
authors.forename: Markadieu
authors.initials: M
authors.lastname: Nicolas
authors.forename: Crutzen
authors.initials: C
authors.lastname: Raphael
authors.forename: Donfack Jean
authors.initials: DJ
authors.lastname: Hubert
authors.forename: Dongo
authors.initials: D
authors.lastname: Etienne
authors.forename: Kamtchouing
authors.initials: K
authors.lastname: Pierre
authors.forename: Dimo
authors.initials: D
authors.lastname: Theophile
authors.forename: Beauwens
authors.initials: B
authors.lastname: Renaud
mesh_terms: D000241:Adenosine / Q000378:metabolism; D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002460:Cell Line; D002478:Cells, Cultured; D003921:Diabetes Mellitus, Experimental / Q000188:drug therapy / Q000378:metabolism; D004232:Diuretics / Q000494:pharmacology*; D007328:Insulin / Q000378:metabolism; D029586:Moraceae / Q000737:chemistry*; D009318:Natriuresis / Q000187:drug effects; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D010766:Phosphorylation / Q000187:drug effects; D010936:Plant Extracts / Q000494:pharmacology*; D051381:Rats; D043682:Receptor, Adenosine A1 / Q000378:metabolism; D012964:Sodium / Q000378:metabolism; D014982:Xenopus laevis
chemical_list: D004232:Diuretics; D007328:Insulin; D010936:Plant Extracts; D043682:Receptor, Adenosine A1; D012964:Sodium; D019869:Phosphatidylinositol 3-Kinases; D000241:Adenosine