Bacopa Monniera
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Monograph Bacopa monniera Bacopa monniera Introduction Bacopa monniera, also referred to as Bacopa monnieri, Herpestis monniera, water hyssop, and “Brahmi,” has been used in the Ayurvedic system of medicine for centuries. Traditionally, it was used as a brain tonic to enhance memory development, learning, and concentration,1 and to provide relief to patients with anxiety or epileptic disorders.2 The plant has also been used in India and Pakistan as a cardiac tonic, digestive aid, and to improve respiratory function in cases of bronchoconstriction.3 Recent research has focused primarily on Bacopa’s cognitive-enhancing effects, specifically memory, learning, and concentra- tion, and results support the traditional Ayurvedic claims. Research on anxiety, epilepsy, bronchitis and asthma, irritable bowel syndrome, and gastric ulcers also supports the Ayurvedic uses of Bacopa. Bacopa’s antioxidant properties may offer protection from free radical damage in cardiovascular disease and certain types of cancer. Bacoside A OH O H HOH2C HO O H H HO H H OH O O H H HO H OH H H O H CH2OH Description Bacopa monniera, a member of the Scrophulariaceae family, is a small, creeping herb with numer- ous branches, small oblong leaves, and light purple flowers. In India and the tropics it grows naturally in wet soil, shallow water, and marshes. The herb can be found at elevations from sea level to altitudes of 4,400 feet, and is easily cultivated if adequate water is available. Flowers and fruit appear in summer and the entire plant is used medicinally.2,4 Alternative Medicine Review ◆ Volume 9, Number 1 ◆ 2004 Page 79 Copyright©2004 Thorne Research, Inc. All Rights Reserved. No Reprint Without Written Permission Bacopa monniera Monograph Active Constituents and Clinical Indications Pharmacokinetics Cognitive Effects Compounds responsible for the pharmaco- Adults logical effects of Bacopa include alkaloids, saponins, Bacopa monniera has been studied clini- and sterols. Many active constituents – the alkaloids cally for its acute and chronic effects on cognitive Brahmine and herpestine, saponins d-mannitol and function. In adults, it appears only chronic admin- hersaponin, acid A, and monnierin – were isolated istration is associated with cognitive-enhancing in India over 40 years ago. Other active constituents effects. In a double-blind, placebo-controlled trial have since been identified, including betulic acid, of 38 healthy volunteers (ages 18-60), subjects stigmastarol, beta-sitosterol, as well as numerous were given a single dose of 300 mg Bacopa bacosides and bacopasaponins. The constituents re- monniera extract (standardized to 55-percent com- sponsible for Bacopa’s cognitive effects are bacosides bined bacosides A and B) or placebo. Subjects A and B.5-9 were tested two hours after drug administration, coinciding with maximum pharmacodynamic ef- Mechanisms of Action fect. Acute administration of this dose of Bacopa Since Bacopa’s primary therapeutic use is extract resulted in no significant changes in cog- to enhance cognitive function, most research has fo- nitive function when compared to baseline val- cused on the mechanism behind these properties. The ues. Parameters assessed included attention, work- triterpenoid saponins and their bacosides are respon- ing and short-term memory, verbal learning, de- sible for Bacopa’s ability to enhance nerve impulse cision making, memory consolidation, executive transmission. The bacosides aid in repair of dam- processes, planning and problem solving, speed aged neurons by enhancing kinase activity, neuronal of information processing, and motor responsive- 20 synthesis, and restoration of synaptic activity, and ness. ultimately nerve impulse transmission.10 On the other hand, significant cognitive- Loss of cholinergic neuronal activity in the enhancing benefits have been demonstrated with hippocampus is the primary feature of Alzheimer’s more chronic administration of Bacopa extracts. disease.11 Based on animal study results, bacosides Australian researchers conducted a double-blind, appear to have antioxidant activity in the hippocam- placebo-controlled, 12-week trial utilizing the pus, frontal cortex, and striatum.12 Animal research same patient selection criteria and same dose of has shown Bacopa extracts modulate the expression Bacopa extract (300 mg daily) containing 55-per- of certain enzymes involved in generation and scav- cent combined bacosides. Forty-six healthy vol- enging of reactive oxygen species in the brain.13 In unteers (ages 18-60) were randomly and evenly vitro research has shown Bacopa exerts a protective divided into treatment and placebo groups. The effect against DNA damage in astrocytes14 and hu- same series of tests administered in the acute dos- man fibroblasts.15 age trial were administered at baseline, five, and In animals Bacopa has a relaxant effect on 12 weeks after treatment began. At the end of the pulmonary arteries, aorta, trachea, and ileal and bron- 12-week study, results indicated a significant im- chial tissue, possibly mediated by inhibition of cal- provement in verbal learning, memory consolida- cium-ion influx into cell membranes.16 Bacopa ap- tion, and speed of early information processing in pears to stabilize mast cells in vitro,17 and possesses the treatment group compared to placebo. These anti-inflammatory activity via inhibition of prostag- effects were not observed at baseline or at five landin synthesis and lysosomal membrane stabiliza- weeks. These results may be attributed to Bacopa’s 18 antioxidant properties and/or its effect on the cho- tion. In vitro research suggests an anticancer effect 21 for Bacopa extracts, possibly due to inhibition of linergic system. DNA replication in cancer cell lines.19 Page 80 Alternative Medicine Review ◆ Volume 9, Number 1 ◆ 2004 Copyright©2004 Thorne Research, Inc. All Rights Reserved. No Reprint Without Written Permission Monograph Bacopa monniera Children Importantly, the Bacopa extract did not induce Bacopa’s ability to modulate or enhance amnesia, side effects associated with Lorazepam, cognitive function has also been studied in chil- but instead had a memory-enhancing effect.24 dren. Forty children from rural India (ages 6-8) A one-month, limited clinical trial of 35 were divided into treatment and placebo groups patients with diagnosed anxiety neurosis demon- of 20 children each. Children in the treatment strated that administration of Brahmi syrup (30 group received one teaspoon Bacopa syrup (350 mL daily in two divided doses, equivalent to 12 g mg Bacopa powder/teaspoonful) three times daily dry crude extract of Bacopa) resulted in a signifi- for three months. The placebo group received cant decrease in anxiety symptoms, level of anxi- Syrup Simplex (details not available). A series of ety, level of disability, and mental fatigue, and an tests measuring visuomotor and perceptual abili- increase in immediate memory span. Other ties and memory span were administered at changes noted were increased body weight, de- baseline and at the end of treatment. Significant creased respiration rate, and decreased systolic improvements were noted in strengthened explor- blood pressure.25 atory drive (as measured by maze learning), im- proved perceptual images of patterns, and in- Epilepsy creased perceptual organization and reasoning Although Bacopa has been indicated as a ability (as measured by reaction time). This study, remedy for epilepsy in Ayurvedic medicine, re- 22 however, was not double-blinded. search in animals shows anticonvulsant activity A double-blind, randomized, placebo- only at high doses over extended periods of time. controlled trial of 36 children with diagnosed at- Early research in India demonstrated that tention deficit/hyperactivity disorder was con- hersaponin (an active constituent) exhibited pro- ducted over a 16-week period. Nineteen children tection against seizures in mice.26 A more recent received an extract of Bacopa (standardized to Indian study also examined the anticonvulsant contain 20-percent bacosides) at a dosage of 50 properties of Bacopa extracts in mice and rats. mg twice daily for 12 weeks, and 17 subjects were Researchers determined that intraperitoneal injec- given a placebo. The mean age of the children in tions of high doses of Bacopa extract (close to 50 the two groups was 8.3 years and 9.3 years, re- percent of LD50) given for 15 days demonstrated spectively. Active drug treatment was followed by anticonvulsant activity. When administered four weeks of placebo and the children were evalu- acutely at lower doses (approaching 25 percent of ated on numerous cognitive function tests at LD50), anticonvulsant activity was not observed.27 baseline, four, eight, 12, and 16 weeks. A signifi- cant benefit was observed in Bacopa-treated sub- Bronchitis and Asthma jects at 12 weeks as evidenced by improvement on sentence repetition, logical memory, and paired Animal studies have demonstrated associate learning tasks. Evaluation showed these Bacopa extracts have a relaxant effect on chemi- improvements were maintained at 16 weeks (af- cally-induced bronchoconstriction, probably via ter four weeks placebo administration).23 inhibition of calcium influx into cell membranes. An earlier in vitro study by Dar and Channa dem- onstrated the broncho-vasodilatory activity of B. Anxiety and Depression monniera on rabbit and guinea pig trachea, pul- Bacopa’s traditional use as an anti-anxiety monary artery, and aorta.28 A subsequent rat study remedy in Ayurvedic medicine is supported