Dietary supplementation with Salvia sahendica attenuates memory deficits, modulates CREB and its down-stream molecules and decreases apoptosis in amyloid beta-injected rats.

Abstract

Herein, we investigated the effect Salvia sahendica (S. sahenica) extract, an endemic plant of Iran on the improvement of learning and memory deficits in amyloid beta-(Aβ) injected rats. In order to test this hypothesis, we pretreated rats with S. sahendica 1 week prior to Aβ injection, then performed Morris water maze test. Besides, we studied the molecular factors involved in neuronal plasticity and apoptosis such as Ca(2+)/cAMP-response element binding protein (CREB), c-fos, Peroxisome proliferator-activated receptor γ co-activator 1α (PGC-1α), Poly (ADP-ribose) polymerase (PARP) and caspase-3. Moreover, we used Terminal-Transferase dUTP Nick End Labeling (TUNEL) technique to detect apoptosis in the hippocampus of Aβ-injected rats. Results showed that S. sahendica could improve learning and memory in the behavioral test. The results of molecular section showed that CREB, c-fos and PGC-1α levels attenuated in the Aβ-injected rats in comparison with control group. These decreases were attenuated 58, 62, 57% respectively in S. sahendica-pretreated rats. This dietary supplementation could decrease apoptotic factors including caspase-3, PARP and TUNEL positive cells as well. Collectively, the present result from behavioral testing and biochemical analysis demonstrated that S. sahendica treatment for 1 week protected against apoptosis and memory deficits in Aβ-injected rats.