Long-term Treatment with Oriental Medicinal Herb Artemisia princepsAlters Neuroplasticityin a Rat Model of Ovarian Hormone Deficiency

Abstract

Artemisia princeps (AP) is a flowering perennial used as a traditional medicine and dietary supplement across East Asia. No study has yet assessed its effects on synaptic plasticity in hippocampus and much less in a model of ovarian hormone deficiency. We examined the influence of chronic oral AP ethanol extract treatment in ovariectomized rats on the induction of long-term depression in a representative synapse (CA3-CA1) of the hippocampus. Ovariectomized rats demonstrated lower trabecular mean bone mineral densities than sham, validating the establishment of pathology. Against this background of pathology, AP-treated ovariectomized rats exhibited attenuated long-term depression (LTD) in CA1 relative to water-treated controls as measured by increased field excitatory post-synaptic potentials (fEPSP) activation averages over the post-stimulation period. While pathological significance of long-term depression (LTD) in ovariectomized rats is conflicting, that AP treatment significantly affected its induction offers justification for further study of its influences on plasticity and its related disorders.

Curcumin Alters Neural Plasticity and Viability of Intact Hippocampal Circuits and Attenuates Behavioral Despair and COX-2 Expression in Chronically Stressed Rats

“…The MEA system is composed of a 64-channel array with four stimulating and 60 recording electrodes (STG1004; Multi Channel Systems GmbH, Germany), an amplifier (MEA1060; Multi Channel Systems GmbH, Germany), temperature control units (Multi Channel Systems GmbH, Germany), and data acquisition software ( http://www.multichannelsystems.com/ ) [ 15 ]. The amplifier was placed in a Faraday cage.…”

“…MC_Rack (v.3.2.1.0, Multi Channel Systems) was used to digitize the analog MEA signal and isolate EPSPs from triggering amplitudes greater than 40 mV, and a custom MATLAB (v.7.0.1, Mathworks, Inc.) program was used to remove stimulus artifacts and integrate the evoked field potential trajectory, as reported previously [ 15 , 16 ].…”

ESP‐102, a Combined Herbal Extract of Angelica gigas, Saururus chinensis, and Schisandra chinensis, Changes Synaptic Plasticity and Attenuates Scopolamine‐Induced Memory Impairment in Rat Hippocampus Tissue

“…For this purpose it is logical to develop novel therapeutic candidates from traditional herbal medicines and botanical drugs with already proven efficacy and safety [ 6 ]. Based on previous findings of the neuroprotective activity of ESP-102, it was presumed that it might affect hippocampal neural plasticity [ 11 ]. Therefore, we examined the effects of ESP-102 on the conditions of LTP and LTD in organotypic hippocampal slice cultures from 7-day-old Sprague-Dawley rats.…”

“…MC_Rack (v.3.2.1.0, Multi Channel Systems) was used to digitize the analog MEA signal and isolate EPSPs from triggering amplitudes greater than 40 mV, and a custom MATLAB (v.7.0.1, Mathworks, Inc.) program was used to remove stimulus artifacts and integrate the evoked field potential trajectory, as reported previously [ 6 , 11 ].…”

“…This results in a dramatic change in the working nature of the whole neural network because a strong TBS might not be localized in the vicinity of target but spread out to the whole network [ 7 , 8 ]. Recently accumulating knowledge about the LTP mechanism has indicated that LTP enhances learning and memory processes in various pathological conditions [ 9 – 11 ]. Improved understanding of synaptic plasticity will help us verify the pharmacological effects of drug candidates and their effects on the neuronal network [ 9 ].…”