Allantoin

Extracted from Dioscorea opposite Thunb. (In Vitro) :Allantoin is a well-known cosmetic ingredient reported to have anti-oxidative and anti-inflammatory activities. Allantoin attenuates apoptosis and cytotoxicity and increased the viability of STZ-induced β-cells in a dose-dependent manner. Allantoin decreases the level of caspase-3 and increases the level of phosphorylated B-cell lymphoma 2 (Bcl-2) expression. Allantoin has been demonstrated to activate imidazoline 3 (I3) receptors. (In Vivo) :The subchronic administration of allantoin (1, 3 or 10 mg/kg, for 7 days) significantly increases the latency time measured during the passive avoidance task in scopolamine-induced cholinergic blockade and normal naive mice. Allantoin treatment (3 or 10 mg/kg, for 7 days) also increases the expression levels of phosphorylated phosphatidylinositide 3-kinase (PI3K), phosphorylated protein kinase B (Akt) and phosphorylated glycogen synthase kinase-3β (GSK-3β) . Allantoin significantly increases the neuronal cell proliferation of immature neurons in the hippocampal dentate gyrus region. Daily injection of allantoin for 8 days in STZ-treated rats significantly lowers plasma glucose and increases plasma insulin levels . Allantoin decreases blood pressures in SHRs at 30 minutes, as the most effective time. Also, this antihypertensive action is shown in a dose-dependent manner from SHRs treated with allantoin. Moreover, in anesthetized rats, allantoin inhibits cardiac contractility and heart rate. Also, the peripheral blood flow is markedly increased by allantoin.