Beta-boswellic acid and ethanolic extract of Olibanum regulate the expression levels of CREB-1 and CREB-2 genes

Abstract

Physiological studies confirm improvement of memory by Olibanum, a resin from Boswellia species, while little is known about the molecular mechanism by which it affects memory performance. Two master transcription factors, CREB-1 and CREB-2, regulate downstream memory-related genes expression, leading to the long-term memory potentiation. This study addresses the effects of Beta-boswellic acid (β-BA), the main ingredient of Olibanum, and ethanolic extract of the resin from Boswellia serrata on the expression of CREB-1 and CREB-2 genes in B65 cell line. B65 cells were treated with β-BA) or ethanolic extract of Olibanum in different dose and time intervals and the cell viability/toxicity was measured by MTT assay. Total RNA was extracted from the treated and untreated control cells and cDNA was synthesized. The expression levels of CREB-1 and CREB-2 genes were quantified by Real-time PCR. MTT assays revealed 50% inhibitory concentrations of 42.05, 29.63 and 21.78 μg/ml for ethanolic extract of Olibanum and 89.54, 44.05 and 21.12 µM for β-BA at 24, 48 and 72h time intervals respectively. Both β-BA and ethanolic extract of Olibanum altered CREB-1 and CREB-2 genes expression levels in time-dependent but not in dose-dependent way. However, β-BA showed stronger and more stable effects. The expression levels of the both genes followed an alternate upregulation and downregulation pattern, but in opposite directions, in response to the both solutions with the progress of time. These results suggest that Olibanum possibly improves memory performance, at least partially, by regulating the levels of CREB-1 and CREB-2 transcription factors via positive/negative-feedback loops.