Herbal Support for Brain Health and Beyond

The use of plants to support brain health and protect against cognitive decline has been a part of traditional herbal practice for millennia, with many originating from Eastern medical philosophies such as Ayurvedic and Traditional Chinese Medicine. A substantial amount of scientific curiosity into the mechanisms that plants can impart upon the brain and nervous system has since been conducted, with a range of in vitro, in vivo, and clinical studies across various ages and life stages demonstrating support for such beneficial effects as:

• Supporting working memory, storage, recall, learning, and knowledge retention.₁
• Enhancing attention, focus and concentration.₁
• Slowing or preventing the onset of age or Alzheimer’s-related cognitive decline (e.g. via disrupted cholinergic transmission, reducing oxidative or ischemic neuronal damage and beta-amyloid formation).₂

Though the term is not solely applied to plants, these herbs are often referred to as nootropics (pronounced “no-uh-TROH-pic”), which can be any substance considered to enhance memory and learning, improve cognition, and impart neuroprotective effects. Many herbs with nootropic properties will also often have complementary effects upon the body’s stress response, helping to reduce anxiety, inflammation, and ultimately help result in improved mental and emotional well-being. While simultaneously benefiting brain health, the overlapping actions of many herbs useful to enhancing cognition include adaptogens, nervine tonics, and nervine relaxants.

Converging lines of historical, mechanistic, and clinical evidence all suggest that herbs have the potential to support brain health while concurrently mitigating the damaging effects of stress (mental, emotional, and oxidative). Considered beneficial at any age, these plants can provide a well-tolerated, preventative treatment for declines in cognitive function associated with disease or aging, and for anyone looking to sharpen the mind while operating under stress.

Bacopa

Bacopa (Bacopa monnieri) also known as brahmi or water hyssop, is a treasured Ayurvedic herb native to India where it has been regularly consumed for thousands of years as a rejuvenating tonic to promote longevity and strengthen cognitive function. Consistently found in many Ayurvedic preparations prescribed for cognitive dysfunction, Bacopa was initially described around the 6th century A.D. as an herb taken to sharpen intellect and improve memory and concentration. It was often prescribed for continuous daily use.₃

Bacopa’s mechanism of action has been studied extensively using in vitro systems and animal models and, with chronic and moderate administration appearing to nourish rather than deplete neurons, confirming the observations of over a millennia of Ayurvedic study. The most studied constituents in Bacopa that appear to be of primary therapeutic importance are the bacosides (particularly bacoside A), which are triperpenoid saponins that demonstrate significant antioxidant and neuroprotective effects. Several pharmacological activities of bacosides that have been observed include:₃

• Acetylcholinesterase inhibition and choline acetyltransferase activation
• β-amyloid reduction
• Increased cerebral blood flow
• Monoamine potentiation and modulation

Animal models evaluating cognitive performance have shown significantly better acquisition, improved retention, and faster reaction times compared to controls, and suggest considerable protection against age-related neurodegeneration without toxicity or tolerance formation.₄

Clinical studies with Bacopa have focused on its potential to support memory, focus, and cognition across various life stages and particularly with chronic use ( > 3 months)._5-7 From significantly improving memory in seniors, to improved cognitive and behavioral outcomes in children and adolescents with attention deficit hyperactivity disorder._8-11  Many human trials have also noted additional benefits such as attenuation of task-induced ratings of stress and fatigue, and in one case a simultaneous significant reduction in anxiety.₁₂ One study which compared the nootropic effects of Bacopa to both Panax ginseng and modafinil (an eugeroic wakefulness drug), found that Bacopa produced the most consistent and largest effect size of the three for a variety of auditory and verbal learning tasks.₁₃

Rosemary

Rosemary (Rosmarinus officinalis) leaf has a long history as an herb associated with remembrance both literally and symbolically, and in classical writings it is said to “stimulate the mind, memory, and the senses”.₁₄ In ancient Egypt it was used in the process of mummification, and later by the Greeks and Romans as a memory enhancer. In fact, Greek students were said to wear sprigs or garlands of rosemary at times of high educational demand.₁

The leaf is rich in aromatic volatile oils (e.g. 1,8-cineole, borneol, and a-pinene) and phenolics such as rosmarinic, carnosic, and ursolic acids.₁₅ In aromatherapy, Rosemary oil is regarded as a tonic towards the central nervous system and is often used to strengthen mental clarity and improve memory.₁₆ In one clinical study, the inhalation of Rosemary was shown to provide increased alertness and lowered anxiety ratings, producing a more relaxed yet alert state while performing mathematical calculations.₁₇

Eleuthero

Eleuthero (Eleutherococcus senticosus), sometimes referred to as “Siberian Ginseng” is a root with a long history of use in Traditional Chinese Medicine to reinforce Qi and calm the nerves in cases of stress and insomnia.₁₈ More modern uses have focused on its role as an adaptogen which can increase mental alertness and physical performance particularly when under stress. As cognitive support, Eleuthero therefore becomes particularly helpful in cases of brain fog due to overwhelm and/or high-pressure working conditions, aiding the body’s ability to perform and withstand such mental stressors.

The therapeutic properties of Eleuthero are likely due to the combined effect of many constituents, however syringaresinol diglucosides (e.g. eleutherosides D and E) are likely the most pharmacologically important for increasing resistance to stress and fatigue.₁₉ Eleuthero extract has been shown to improve short-term memory in humans, with other trials demonstrating an ability to improve mental and physical performance and stamina of workers, as well as endurance and concentration in athletes._20,21 In animals with atrophic neuritis those given Eleuthero extract were capable of protecting against neuronal damage, atrophy, and cell death, thus demonstrating the potential to regenerate damaged brain neurons.₁₉

Schisandra

Schisandra (Schisandra chinensis or Wu Wei Zi) berry is a tart fruit commonly used in Traditional Chinese Medicine formulations to calm the nervous system in cases of anxiety and insomnia, and also to aid in memory loss.₂₂ It also has a reputation as an adaptogen and nervine tonic, however there is limited available evidence indicating its ability to increase mental efficiency outside of animal studies. In one human study where Schisandra was given alongside other herbal adaptogens (Eleuthero and Rhodiola), cognitive improvements such as improved accuracy and attention were noted while under stressful studying conditions when compared against placebo.₂₃

Lignans found in the berry (specifically dibenzocyclooctene lignans e.g. schisandrins and gomisins) have been extensively studied in animal models and have demonstrated many beneficial brain health and nervous system effects, showing significant improvements in cognitive and behavioural functions including:

• Increasing memory and cognition in the presences of excessive beta-amyloid pigmentation, suggesting potential use in symptoms of Alzheimer’s Disease.₂₄
• Reducing activation of the hypothalamus-pituitary-adrenal axis, attenuating rises in cortisol and catecholamines associated with stress and physical activity, and reducing behaviours associated with anxiety._25,26
• Neuroprotective effects against stress-induced senescence, mitochondrial dysfunction, and oxidative damage within the brain._27,28

References

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