Bacopa monnieri is also in my list. The following has some updated details published in September last year -
Molecules. 2012 Sep 26;17(10):11391-420.
Recent updates in redox regulation and free radical scavenging effects by herbal products in experimental models of Parkinson's disease.
Koppula S, Kumar H, More SV, Lim HW, Hong SM, Choi DK.
Department of Biotechnology, Konkuk University, Chungju, Korea.
Parkinson's disease (PD) is a complex multifactorial disease marked by extensive neuropathology in the brain with selective yet prominent and progressive loss of mid-brain dopaminergic neurons. The etiological factors involved in the development of PD are still elusive, but oxidative stress arising when reactive oxygen species (ROS) exceed amounts required for normal redox signaling is considered one of the major factors. ROS cause oxidative damage to proteins, lipids, and DNA and are one of the most prominent factors related to neurodegeneration. Pre-clinical and clinical studies clearly demonstrate the effectiveness of oxidative stress in the pathogenesis of PD. Therefore, regulation of redox signaling and inhibiting excess ROS would contribute greatly not only to extend longevity but also to ameliorate the progression of dopaminergic cell death seen in patients with PD. Several herbal products are beneficial for maintaining nerve cell function and for treating various neurodegenerative disorders by reducing oxidative stress. Here, we summarize the recent knowledge concerning promising herbs that have shown significant beneficial effects based on regulation of redox status and ROS inhibition in toxin-induced PD models.
6.5. Bacopa monnieri
B. monnieri Linn. is in the family Plantaginaceae and a common herb that grows throughout India,
Nepal, Sri Lanka, China, Taiwan, Vietnam, as well as in Florida, Hawaii and other southern states of
the US where it grows in damp conditions by ponds or in bogs. B. monnieri has been used in Indian
Ayurvedic traditional medicine for almost 3,000 years and is classified as one of the most important
herbs used to improve memory and cognition as well as a potent nerve tonic [108,109]. B. monnieri is
well tolerated without side effects , and the LD50 in rats is as high as 2.7 g/kg when
administrated orally . In a study conducted by Singh et al. , B. monnieri protected a DAergic
SK-N-SH cell line against MPP+- and paraquat-induced toxicity in various survival assays. B. monnieri
pretreatment (10 mg/mL) significantly attenuated the generation of intracellular ROS and decreased
mitochondrial superoxide levels. Furthermore, B. monnieri treatment activated the Nrf2 pathway by
modulating Keap1 expression, thereby upregulating endogenous GSH synthesis. The authors
concluded that B. monnieri might be useful in age-related neurodegeneration including PD by
preserving cellular redox homeostasis and mitochondrial activities . In an earlier study Hosamani
and Muralidhara , investigated a standardized B. monnieri powder against rotenone-induced
oxidative stress and neurotoxicity in Drosophila melanogaster exposed to B. monnieri powder (0.05
and 0.1%) for 7 days in the diet. The results showed significant attenuation in the levels of endogenous
oxidative markers such as malondialdehyde, hydroperoxide, and protein carbonyl content. Complete
protection was offered by B. monnieri against rotenone (500 mM)-induced oxidative stress and further
markedly inhibited DA depletion (head region, 33%; body region, 44%) in the flies. The authors
hypothesized that B. monnieri may have the ability to mitigate rotenone-induced oxidative stress .
In much more recent studies, Shinomol et al. tested the hypothesis that a B. monnieri extract could
offset neurotoxicant-induced oxidative dysfunction in the developing brain of rotenone and
3-nitropropionic acid mouse models [113–116]. They indicated that rotenone-induced (1.0 mg/kg
b.w./day, i.p.) oxidative stress and cell death in vitro was attenuated significantly by pretreatment with
B. monnieri (2, 4, and 6 μg) in DAergic N27 cell lines. In vivo studies revealed that B. monnieri
(5 mg/kg b.w. once daily for 7 days, i.p.) normalized the levels of oxidative markers
(malondialdehyde, ROS, and hydroperoxides) and restored depleted GSH levels in rotenone-induced
(1 mg/kg b.w. /day for 7 days) mice. B. monnieri also effectively normalized protein carbonyl content
in all brain regions, suggesting an ability to prevent protein oxidation. Furthermore, oxidative stress
and mitochondrial dysfunction in DAergic (N27) cells and prepubertal mouse brain induced by
3-nitropropionic acid were significantly attenuated as evidenced by restoration of the ETC enzyme
Molecules 2012, 17 11400
activities (NADH: ubiquinone oxidoreductase, NADH: cytochrome c reductase, succinate-ubiquinone
oxidoreductase, and cytochrome c oxidase) as well as mitochondrial viability. The activities of
antioxidant enzymes (SOD, GPx, glutathione reductase, and thioredoxin reductase), Na (+), K (+)-ATPase,
and citric acid cycle enzymes in the striatum that were discernible among 3-NPA mice were restored
significantly upon B. monnieri pretreatment. In addition, pretreatment with B. monnieri for 10 days
followed by a 3-NPA challenge (75 mg/kg b.w./day, i.p.) completely prevented 3-NPA-induced
oxidative dysfunction in the striatum and other brain regions. Elevated oxidative marker levels
(malondialdehyde, ROS, hydroperoxide, and protein carbonyls) were predominantly abolished among
mice given B. monnieri prophylaxis. The neuroprotective effects of B. monnieri may be wholly or in
part related to its propensity to scavenge free radicals, maintain redox status, and upregulate
antioxidant machinery in striatal mitochondria. The ability of a B. monnieri ethanol extract to enhance
reduced glutathione and antioxidant defenses in brain regions has been hypothesized for its potent
neuroprotective action .
Bacopa monnieri (过长沙) is not so popular in China and East Asia than it is in India and maybe also Sri Lanka. The good news is Bacopa Monnieri Extract is available here. I am going to try after I know better about it.