The beneficial properties of Bacopa monnieri, both in traditional use and scientific studies, are notable, particularly for supporting cognitive and memory functions. Additionally, its positive impact on promoting relaxation and supporting brain health is well recognized.
Antioxidant action
The results of a recent study suggest that the cognition promoting functions of Bacopa monnieri may be partially attributed to the antioxidant effects of the bacosides. Currently, a number of deteriorative processes in the body are attributed to the action of damaging free radicals. During the physiological process of respiration, inhaled and tissue incorporated oxygen oxidizes cellular components and biomolecules. This process results in the generation of oxidative products, free radicals, and reactive oxygen species when titled towards excessive activity by external factors (e.g. improper nutrition) or internal factors (e.g. disease). These free radicals are highly reactive chemical molecules, which react with biological compounds causing tissue damage by a process called “free radical pathology”.
The aging process is often associated with the natural progression of cellular and tissue changes over time, influenced by oxidative stress. The human body is equipped with antioxidant defenses to help manage oxidative stress, including enzymes like superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX). With age, these defenses may require additional support to maintain balance and support overall health, highlighting the importance of nurturing our body’s ability to sustain these protective mechanisms.
Lipid peroxidation is essentially a “free radical chain reaction” involving the following stages:
Initiation
Hydrogen is abstracted from a polyunsaturated fatty acid side chain by a free radical species:
Propagation
The fatty acid side chain peroxyl radical -CO2 * attacks adjacent fatty acid side chains.
The propagation continues, leading to the accumulation of lipid peroxides in the membranes, destabilization of the membranes and the entry of damaging ions. Peroxyl radicals attack ions as well as membrane proteins. An antioxidant terminates the propagation of free radicals either by accepting and quenching them or by retarding the “initiation” step by reducing the generation of free radicals.
One study determined the effects of alcohol and hexane extracts of Brahmi on lipid peroxidation induced by ferrous sulfate and cumene hydroperoxide in rat liver homogenate. The alcohol fraction of Bacopa monnieri furnished greater protection against both inducers, ferrous Sulfate, and cumene peroxide. The table indicates the effective inhibitory doses.
The results were also compared with known antioxidants, tris (2-amino-2-hydroxymethyl-1,3-propanediol) (a hydroxyl trapper), EDTA (a metal chelator) and the natural antioxidant, vitamin E. (Note: 100 mg of the alcoholic extract of Brahmi was equivalent to 247 mg of EDTA (0.66mM) and 58 mg of vitamin E.) Tris did not show any protective effect, while Brahmi (alcoholic extract), EDTA and vitamin E, offered dose-dependent protection against ferrous sulfate-induced peroxidation
| Extract | ED50 (mg) Ferrous sulfate |
ED50 (mg) Cumene hydroperoxide |
|---|---|---|
| Alcoholic extract | 100 | 177 |
| Hexane extract | 290 | 400 |
The authors also observed that Brahmi only slightly protect against the oxidation of reduced glutathione at doses lower than 100 mg/ml, while higher concentrations enhanced the rate of oxidation. The authors concluded that Brahmi’s mechanism of antioxidant action could be attributed to metal chelation at the initiation level of the free radical-induced, chain reaction or the quenching of free radicals at propagation level.
A more recent study explored the antioxidant activity of Bacopa monnieri in the rats’ frontal cortex, striatum, and hippocampus. The levels of the antioxidant enzymes, SOD, CAT, and GPX were measured following the administration of a standardized extract of Bacopa monnieri (bacoside A content 82 ± 5%, administered in doses of 5 mg/kg and 10 mg/kg orally) for 7, 14 and 21 days. These results were compared with the effects induced by (-) deprenyl (selegiline hydrochloride, a well-known neurological antioxidant, 2 mg/kg orally) for the same time period. The enzyme activities were investigated in the frontal cortex, striatum, and hippocampus after 14 and 21 days.
After 14 and 21 days, Bacopa monnieri extract induced a dose-related increase in SOD, CAT and GPX activities in all brain regions investigated, while (-) deprenyl induced an increase in the frontal cortex and striatum but not the hippocampus. The results suggest that Bacopa monnieri extract exhibits significant antioxidant effects, and these effects extend to the hippocampus, the seat of memory and cognition, unlike deprenyl. The authors concluded that increased free radical scavenging may explain, at least in part, the cognition-facilitating action of Bacopa monnieri extract documented in the ancient ayurvedic texts and in the modern scientific literature.