(-)-α-bisabolol prevents neuronal damage and memory deficits through reduction of proinflammatory markers induced by permanent focal cerebral ischemia in mice.

The pathophysiology of ischemic stroke involves multiple events such as inflammation and oxidative stress which will lead to neuronal death and cognitive deficits. The (-)-α-bisabolol is a monocyclic sesquiterpene alcohol found in various plants and mainly in Matricaria chamomilla, which exerts antioxidant, anti-inflammatory, and anti-apoptotic activities. The aim of this work was to investigate the neuroprotective effects of (-)-α-bisabolol in mice underwent permanent occlusion of the middle cerebral artery (pMCAO). Animals were treated with (-)-α-bisabolol (50, 100 and 200 mg/kg/day, orally) or vehicle (3% tween 80) one day before and 1 h after pMCAO and the treatment continued once daily for the following five days. The treatment with (-)-α-bisabolol (100 and 200 mg/kg) significantly reduced the infarcted area and neurological deficits caused by pMCAO. (-)-α-bisabolol at the 200 mg/kg dose increased cell viability and decreased neuronal degeneration, as evaluated by cresyl violet and Fluoro-Jade C stainings, respectively. (-)-α-bisabolol also increased the locomotor activity which was reduced by cerebral ischemia and improved pMCAO-induced working, spatial, object recognition, and aversive memories deficits. (-)-α-bisabolol (200 mg/kg) significantly prevented the increase of myeloperoxidase (MPO) activity, TNF-α immunoreactivity in the temporal cortex, and the increase of iNOS both in the temporal cortex and in the striatum. (-)-α-bisabolol treatment also prevented astrogliosis in these areas. These data showed that (-)-α-bisabolol provides neuroprotective action probably due to its anti-inflammatory activity, although other mechanisms cannot be discarded.

alpha,beta-amyrin, a natural triterpenoid ameliorates L-arginine-induced acute pancreatitis in rats.

AIM: To study the beneficial effects of triterpene alpha,beta-amyrin and the underlying mechanisms in an experimental pancreatitis model. METHODS: Acute pancreatitis was induced in five groups of rats (n = 8) by L-arginine (2 x 2.5 g/kg, intraperitoneal, 1 h apart) and 1 h later, they received a single oral dose of alpha,beta-amyrin (10, 30 and 100 mg/kg), methylprednisolone (30 mg/kg) and vehicle (3% Tween 80). A saline (0.9% NaCl) treated group served as a normal control. Efficacy was assessed at 24 h by determination of serum levels of amylase, lipase and pro-inflammatory cytokines [tumor necrosis factor (TNF)-alpha and interleukin (IL)-6], pancreatic myeloperoxidase (MPO) activity, lipid peroxidation [thiobarbituric acid reactive substances (TBARS)], nitrate/nitrite levels, and the wet weight/body weight ratio. Tissue histology and the immunoreactivity for TNF-alpha and inducible nitric oxide synthetase (iNOS) were performed. RESULTS: alpha,beta-amyrin and methylprednisolone treatments significantly (P < 0.05) attenuated the L-arginine-induced increases in pancreatic wet weight/body weight ratio, and decreased the serum levels of amylase and lipase, and TNF-alpha and IL-6, as compared to the vehicle control. Also, pancreatic levels of MPO activity, TBARS, and nitrate/nitrite were significantly lower. Histological findings and TNF-alpha and iNOS immunostaining further confirmed the amelioration of pancreatic injury by alpha,beta-amyrin. CONCLUSION: alpha,beta-amyrin has the potential to combat acute pancreatitis by acting as an anti-inflammatory and antioxidant agent.