Research Progress of GABA Receptors in Alzheimer’s Disease / 中国生物化学与分子生物学报

Alzheimer’s disease (AD) is a progressive neurodegenerative disease with the early symptom of A β plaque, tau hyperphosphorylation neuronal tangle formation in cells. At present, accumulated evidence shows that the changes of GABA receptors are closely related to AD. Some studies have shown that the expression level of each subunit of the GABA receptor changes in AD patients. Therefore, it is speculated that the changes of GABA subunits may be related to the pathogenesis of AD, but there is no better methods to improve AD by targeting GABA receptors. In order to further understand the relationship between the changes of GABA receptors and AD, this paper first reviewed the changes of GABA receptors in AD patients and animal models’ brains and found that there was differential expression in GABA(A) receptor subunits in AD patients. Then we summarized the changes of GABA receptor subunits in Alzheimer database. Based on the data, we found that a few GABA subunits had significant changes. The evidence shows that the change of GABA receptors alters the neural activity in the brain. Other studies have found that the treatment of mice with GABA receptor agonists and antagonists can improve the cognitive ability of mice. We hope that understanding the differential expression of GABA receptors in AD will provide a more accurate target for the treatment of AD.

Identification of a Novel GABAA Receptor Channel Ligand Derived from Melissa officinalis and Lavandula angustifolia Essential Oils.

Aims: Melissa officinalis (Mo) and Lavandula angustifolia (La) essential oils and their major constituents ((E) - caryophyllene, caryophyllene oxide, geranyl acetate, linalool, nerol, Oct-1-en-3-ol, 3-Octanone, myrcene, allo-ocimene, p-cymene and α- terpineol) assessed by GC-MS) which are shared by these two essential oils were probed in an attempt to identify the GABAAR ligand(s). Study Design: [35S] t-butylbicyclophosphorothionate (TBPS) radioligand binding assay to GABAA receptors. In vitro neuronal viability assay. Place and Duration of Study: School of Biological and Biomedical Sciences, Durham University, United Kingdom (December 2012 and January 2013). Results: One of the major component (s) of (Mo), trans-ocimene, inhibited [35S] (TBPS) binding to native GABAA receptors in a concentration-dependent manner with an apparent IC50 of 40μM. Concentrations (0.001 mg/ml) of whole (Mo) were shown to display modest beneficial effects upon neuronal viability while at a higher concentration (0.1 mg/ml) of (Mo) and (La) oils induced a neurotoxicity effect. Conclusion: These data provide the first evidence that allo-ocimene is an neuroactive GABAA R inhibitory component found in both (Mo) and (La), and represents a novel GABAA receptor channel chemotype derived from a natural product.