Ethnopharmacology of Q'eqchi' Maya antiepileptic and anxiolytic plants: effects on the GABAergic system.

Ethnopharmacological Relevance: The Q'eqchi' Maya possess a large selection of plants to treat neurological disorders, including epilepsy and susto (fright), a culture-bound illness related to anxiety disorders.

Aim Of The Study: To investigate the activity of antiepileptic and anxiolytic plants in the GABAergic system, and determine if there is a pharmacological basis for plant selection.

Materials And Methods: Ethanol extracts of 34 plants were tested in vitro for their ability to inhibit GABA-transaminase (GABA-T) or bind to the GABA(A)-benzodiazepine (BZD) receptor, two principal drug targets in epilepsy and anxiety.

Bioassay-guided fractionation of lemon balm (Melissa officinalis L.) using an in vitro measure of GABA transaminase activity.

A novel pharmacological mechanism of action for the anxiolytic botanical Melissa officinalis L. (lemon balm) is reported. The methanol extract was identified as a potent in vitro inhibitor of rat brain GABA transaminase (GABA-T), an enzyme target in the therapy of anxiety, epilepsy and related neurological disorders.

Glutamic acid decarboxylase 65, 67, and GABA-transaminase mRNA expression and total enzyme activity in the goldfish (Carassius auratus) brain.

GAD65 and GAD67 are the two major isoforms of the enzyme that converts glutamate into GABA in a single step reaction. Despite studies describing GAD65 and GAD67 mRNA expression in the mammalian brain, both GAD65 and GAD67 mRNA expression has not yet been fully described for a non-mammalian vertebrate model. Similarly, the expression patterns of GABA-T mRNA, the major enzyme involved in metabolizing GABA, have not been described for any vertebrate.

Ethnopharmacological investigation of plants used to treat susto, a folk illness.

Selected plants used to treat susto, a folk illness recognized by various groups of Latin America, were screened for anxiolytic and/or fear suppression activity in behavioral assays. We found that the plant used by most of the healers interviewed (Adiantum tetraphyllum Humb. & Bonpl.

Expression of recombinant goldfish glutamic acid decarboxylase 65 and evidence for differential pH and PLP responsiveness compared to the human enzyme.

Glutamic acid decarboxylase (GAD) catalyzes the conversion of glutamate to gamma-aminobutyric acid (GABA) that acts as an important inhibitory neurotransmitter in the vertebrate brain, as well as in the regulation of neuroendocrine function. GAD65 and GAD67 are the two main isoforms that exist in vertebrates. The biochemical properties of recombinant forms of goldfish and human GAD65 were examined.