The Psychopharmacology of European Herbs with Cognition-Enhancing Properties

Abstract

Extensive research suggests that a number of plant-derived chemicals and traditional Oriental herbal remedies possess cognition-enhancing properties. Widely used current treatments for dementia include extracts of Ginkgo biloba and several alkaloidal, and therefore toxic, plant-derived cholinergic agents. Several non-toxic, European herbal species have pan-cultural traditions as treatments for cognitive deficits, including those associated with ageing. To date they have not received research interest commensurate with their potential utility. Particularly promising candidate species include sage (Salvia lavandulaefolia/officinalis), Lemon balm (Melissa officinalis) and rosemary (Rosmarinus officinalis). In the case of sage, extracts possess anti-oxidant, estrogenic, and anti-inflammatory properties, and specifically inhibit butyryl- and acetyl-cholinesterase. Acute administration has also been found to reliably improve mnemonic performance in healthy young and elderly cohorts, whilst a chronic regime has been shown to attenuate cognitive declines in sufferers from Alzheimer's disease. In the case of Melissa officinalis, extracts have, most notably, been shown to bind directly to both nicotinic and muscarinic receptors in human brain tissue. This property has been shown to vary with extraction method and strain. Robust anxiolytic effects have also been demonstrated following acute administration to healthy humans, with mnemonic enhancement restricted to an extract with high cholinergic binding properties. Chronic regimes of aromatherapy and essential oil respectively have also been shown to reduce agitation and attenuate cognitive declines in sufferers from dementia. Given the side effect profile of prescribed cholinesterase inhibitors, and a current lack of a well tolerated nicotinic receptor agonist, these herbal treatments may well provide effective and well-tolerated treatments for dementia, either alone, in combination, or as an adjunct to conventional treatments.

Dementia: Treating Patients and Caregivers with Complementary and Alternative Medicine - Results of a Clinical Expert Conference Using the World Café Method

“…The efficacy, effectiveness, and safety of CAM therapies in treating patients with dementia and their caregivers have been only partially scientifically evaluated [9,10,11,12]. According to the Dementia Cochrane Group [13], the scientific evidence for most medical and nonmedical CAM therapies is weak, mainly due to low numbers of clinical studies and methodological shortcomings, and does not allow final conclusions.…”

Does The Mediterranean Diet or Botanicals Influence Alzheimer’s Disease?

“…The herb was commonly used by the Greek and Roman civilizations as a memory enhancer [29]. It is most commonly known for its antioxidant activity, as it has over two dozen different antioxidant constituents, most notable rosmarinic acid [24].…”

“…Melissa extracts have the capability to bind to nicotinic, muscarinic, and GABA A receptors [46,47]. In a clinical setting, lemon balm extracts were found to reduce cognitive impairment in patients with Alzheimer's [29].…”

A aromaterapia científica na visão psiconeuroendocrinoimunológica: um panorama atual da aromaterapia clínica e científica no mundo e da psiconeuroendocrinoimunologia

“…Os efeitos antioxidantes dos óleos essenciais são importantes por possivelmente melhorar funções cognitivas como melhora da memória e retardo de perdas cognitivas em casos de demência e Alzheimer, nos quais há um efeito deletério pela ação de radicais livres a longo prazo, que também ocorre no processo de envelhecimento (BALLARD et al, 2002;SNOW;HOVANEC;BRANDT, 2004;.KENNEDY;SCHOLEY, 2006). Assim como por causar diminuição de agitação, stress psicológico e ansiedade estado, associado a melhora de humor e aumento do nível de calma (ATMACA et al, 2004;HWANG et al, 2006).…”

“…• Ainda temos que destacar novamente os efeitos antioxidantes, que atuam em diversos sistemas de uma forma integral: melhorando funções cognitivas e memória no sistema nervoso (BALLARD et al, 2002;SNOW;HOVANEC;BRANDT, 2004;.KENNEDY;SCHOLEY, 2006), diminuindo agitação, stress psicológico e ansiedade estado, associado a melhora de humor e aumento do nível de calma (ATMACA et al, 2004;HWANG et al, 2006) e ainda melhorando a resposta imune que é suprimida pelos radicais livres.…”