Plantainoside B in Bacopa monniera Binds to Aβ Aggregates Attenuating Neuronal Damage and Memory Deficits Induced by Aβ

Alzheimer's disease (AD) is a progressive neurodegenerative disease characterized by dementia. The most characteristic pathological changes in AD brain include extracellular amyloid-β (Aβ) accumulation and neuronal loss. Particularly, cholinergic neurons in the nucleus basalis of Meynert are some of the first neuronal groups to degenerate; accumulating evidence suggests that Aβ oligomers are the primary form of neurotoxicity. Bacopa monniera is a traditional Indian memory enhancer whose extract has shown neuroprotective and Aβ-reducing effects. In this study, we explored the low molecular weight compounds from B. monniera extracts with an affinity to Aβ aggregates, including its oligomers, using Aβ oligomer-conjugated beads and identified plantainoside B. Plantainoside B exhibited evident neuroprotective effects by preventing Aβ attachment on the cell surface of human induced pluripotent stem cell (hiPSC)-derived cholinergic neurons. Moreover, it attenuated memory impairment in mice that received intrahippocampal Aβ injections. Furthermore, radioisotope experiments revealed that plantainoside B has affinity to Aβ aggregates including its oligomers and brain tissue from a mouse model of Aβ pathology. In addition, plantainoside B could delay the Aβ aggregation rate. Accordingly, plantainoside B may exert neuroprotective effects by binding to Aβ oligomers, thus interrupting the binding of Aβ oligomers to the cell surface. This suggests its potential application as a theranostics in AD, simultaneously diagnostic and therapeutic drugs.

Investigating the Effects of a Multinutrient Supplement on Cognition, Mood and Biochemical Markers in Middle-Aged Adults with 'Optimal' and 'Sub-Optimal' Diets: A Randomized Double Blind Placebo Controlled Trial

Background: Previous randomized controlled trials examining cognitive and mood effects of combination multivitamin supplements in healthy, non-clinical adults have reported mixed results. One purported explanation for this is that the dietary status of participants at the start of supplement interventions may influence the magnitude of the effect of supplementation. Methods: In this study, we evaluated the effect of a multinutrient formula containing B group vitamins, Bacopa monniera and Ginkgo biloba on memory, attention, mood and biochemical markers of nutrient status in middle-aged adults (M = 52.84 years, n = 141) with 'optimal' and 'sub-optimal' diets over 12 weeks. We hypothesised that active supplementation would differentially improve memory and attention in those with a 'sub-optimal' diet. Results: Mixed model, repeated measures analysis revealed that, in comparison to placebo, active treatment was associated with significant increases in B vitamin status (B1, B6, B12). Regarding behavioural outcomes there was no significant benefit to memory (F(1, 113.51) = 0.53, p = 0.470) nor attention (F(1,113.77) = 1.89, p = 0.171) in the whole cohort. Contrary to our hypothesis, there was a significant beneficial effect of supplementation on attentional performance in individuals with an 'optimal' diet prior to supplementation (F(1,57.25) = 4.94, p = 0.030). In the absence of a main effect of supplementation across the entire cohort, there were also a number of significant three-way interactions (treatment by time by diet group) detected in secondary outcomes including lower state anxiety and mental fatigue in those with an 'optimal' diet. Conclusion: These findings suggest that the cognitive benefit of B vitamin and herbal supplementation may be dependent on diet quality, supporting the concepts of 'co-nutrient optimisation' and interdependency of nutrients. This warrants further investigation. This study advocates characterising the diet of participants prior to supplementation as it may influence the effect of a nutraceutical intervention.

Bacopa monniera extract mitigates isoproterenol-induced cardiac stress via Nrf2/Keap1/NQO1 mediated pathway

The present study was aimed to investigate the effect of standardised hydroalcoholic extract of Bacopa monniera (BME) against isoproterenol (ISO) induced cardiac stress. Isoproterenol (85 mg/kg body weight) was administered intraperitoneally to induce cardiac stress in rats. Bacopa monniera extract (BME75 and 150 mg/kg) was orally administered for 21 days followed by ISO on 22nd and 23rd experimental days. ISO caused significant cardiac damage, which was concomitant with increased apoptosis and attenuated expressions of Nrf2, HO-1, and regulating apoptotic protein expressions of Bax, Bcl2 and NOS2. Treatment with BME in rats significantly improved cardiac dysfunction by maintaining cardiac rhythm, myocardial integrity. Decreased oxidative stress by restored expressions of Nrf2, NQO1 and HO-1 followed by elevating antioxidant enzymes and total glutathione levels. Our present results suggest that the BME treatment strengthening the endogenous defence system through Nrf2 modulation and played a key role against cardiac oxidative stress induced by ISO in rats.

Bacopasaponins with cytotoxic activity against human breast cancer cells in vitro

Globally, breast cancer is a serious concern that exhibits a persistent rise in its incidence and related mortality even after significant advancement in the field of cancer research. To find an alternative cure for the disease from natural resources we selected Bacopa monniera, a perennial ethnomedicinal plant popularly used for boosting memory and mental health. We isolated four different types of dammarane saponins, namely bacopasaponins C-F (1-4) from the plant and evaluated their toxic effects on two different types of human breast cancer cell lines-a hormone-responsive MCF7 and a triple-negative MDA-MB-231. Interestingly, MTT assay revealed a dose-dependent toxic effect of all four types of bacopasaponins on both of these cell lines, 4 being the most effective with 48 h-inhibitory concentration (IC₅₀) of 32.44 and 30 µM in MCF7 and MDA-MB-231 respectively. Further, 4 caused significant alterations in normal cytomorphology and induction of apoptosis in both of these cell lines after 48 h of treatment. No caspase-8 activity was detected in these cell lines when exposed to 4 for 2, 24, and 48 h; instead, Western blotting analysis confirmed involvement of either caspase-9 (MCF7) or both caspase-9 and caspase-3 (MDA-MB-231) in the process of apoptosis indicating the occurrence of intrinsic mode. Additionally, at comparable effective doses to cancer, bacopasaponins showed much less toxicity in normal human peripheral blood lymphocytes (≥ 85% cell survival). Overall, the findings project bacopasaponin F, a natural constituent of Bacopa monniera, as an efficient and safer alternative for breast cancer therapeutics.

Chemical structures of constituents from the whole plant of Bacopa monniera

Two new dammarane-type triterpene oligoglycosides, bacomosaponins A and B, and three new phenylethanoid glycosides, bacomosides A, B1, and B2, were isolated from the whole plant of Bacopa monniera Wettst. The chemical structures of the new constituents were characterized on the basis of chemical and physicochemical evidence. In the present study, bacomosaponins A and B with acyl groups were obtained from the whole plant of B. monniera. This is the first report of acylated dammarane-type triterpene oligoglycosides isolated from B. monniera. In addition, dammarane-type triterpene saponins significantly inhibited the aggregation of 42-mer amyloid β-protein.

Possible Involvement of Standardized Bacopa monniera Extract (CDRI-08) in Epigenetic Regulation of reelin and Brain-Derived Neurotrophic Factor to Enhance Memory

Bacopa monniera extract (CDRI-08; BME) has been known to improve learning and memory, and understanding the molecular mechanisms may help to know its specificity. We investigated whether the BME treatment alters the methylation status of reelin and brain-derived neurotropic factor (BDNF) to enhance the memory through the interaction of N-methyl-D-aspartate receptor (NMDAR) with synaptic proteins. Rat pups were subjected to novel object recognition test following daily oral administration of BME (80 mg/kg) in 0.5% gum acacia (per-orally, p.o.; PND 15–29)/three doses of 5-azacytidine (5-azaC; 3.2 mg/kg) in 0.9% saline (intraperitoneally, i.p.) on PND-30. After the behavioral test, methylation status of reelin, BDNF and activation of NMDAR, and its interactions with synaptic proteins were tested. Rat pups treated with BME/5-azaC showed higher discrimination towards novel objects than with old objects during testing. Further, we observed an elevated level of unmethylated DNA in reelin and BDNF promoter region. Up-regulated reelin along with the splice variant of apolipoprotein E receptor 2 (ApoER 2, ex 19) form a cluster and activate NMDAR through disabled adopter protein-1 (DAB1) to enhance BDNF. Observed results suggest that BME regulate reelin epigenetically, which might enhance NMDAR interactions with synaptic proteins and induction of BDNF. These changes may be linked with improved novel object recognition memory.

In vitro effects of standardized extract of Bacopa monniera and its five individual active constituents on human P-glycoprotein activity

1. For centuries Bacopa monniera (BM) has been used as an herbal drug for the treatment of various mental ailments. A chemically standardized alcoholic extract of BM is clinically available over the counter herbal remedy for memory enhancement in children and adults. Consumption of herbal preparations has been reported to alter the function of membrane transporters, especially P-glycoprotein (P-gp), ATP-dependent drug efflux transporter responsible for the development of herb-drug interactions. 2. In the present study, we evaluated the in vitro effect of BM extract and its five individual active constituents (namely, bacopaside I, bacopaside II and bacopasaponin C, bacoside A and bacoside A3) on P-gp function using luminescent P-gp ATPase assay and Rh123 transport assay across human MDR1 gene transfected LLC-GA5-COL150 cell line. 3. It was observed that BM extract and its five individual constituents inhibited both basal activity as well as verapamil-stimulated ATPase activity, suggesting their affinity towards P-gp. Further, BM and its five active constituents inhibited the rhodamine 123 (Rh123) transport across LLC-GA5-COL150 cell monolayer with bacopaside II being the most potent inhibitor of P-gp, which decreased P-gp efflux ratio of Rh123 by fourfold in comparison to control. 4. Our finding may prove beneficial in predicting the potential herb-drug interactions of BM on concomitant medication with P-gp substrate drugs in clinical settings.

Antipsychotic activity of standardized Bacopa extract against ketamine-induced experimental psychosis in mice: Evidence for the involvement of dopaminergic, serotonergic, and cholinergic systems

CONTEXT

Schizophrenia is a chronic disabling psychiatric disorder affecting 1% of the population worldwide. Due to the adverse effects of available antipsychotic medications, recent investigations have focused on the search for well-tolerated, safe molecules from natural resources to control the severity and progression of schizophrenia.

OBJECTIVE

To screen the standardized extract of Bacopa monniera Linn. (Scrophulariaceae) (BM) for its antipsychotic potential in the ketamine-induced psychosis model with mice.

MATERIALS AND METHODS

Graded dose of BM (40, 80, and 120 mg/kg, p.o.) were given to the mice 1 h prior to ketamine administration and tested for positive symptoms and cognitive deficits. A chronic ketamine treatment regimen was used to study the effect of BM on negative symptoms such as immobility enhancement. Each mouse was used once for the behavioral studies.

RESULTS

BM reduced ketamine-induced hyperactivity with an EC50 value of 76.60 mg/kg. The 80 mg/kg dose was used for all other behavior analysis. Pretreatment with BM at 80 mg/kg showed two-fold increases in transfer latency time (TLT) in passive avoidance task. Chronic BM pretreatment (80 mg/kg p.o. daily × 10 d) ameliorated the ketamine-induced enhanced immobility effect by 21% in the forced swim test. BM treatment reversed ketamine-induced increase in monoamine oxidase activity in both cortex and striatum and normalized the acetylcholinesterase activity and the glutamate levels in the hippocampus.

DISCUSSION AND CONCLUSION

Overall our findings suggest that BM possesses antipsychotic properties which might be due to its modulatory action on dopamine, serotonin, and glutamate neurotransmission.

Efficient shoots regeneration and genetic transformation of Bacopa monniera

Bacopa monniera is an important source of metabolites with pharmaceutical value. It has been regarded as a valuable medicinal plant and its entire commercial requirement is met from wild natural population. Recently, metabolic engineering has emerged as an important solution for sustained supply of assured and quality raw material for the production of active principles. Present report describes efficient in vitro multiplication and transformation method for genetic manipulation of this species. MS medium supplemented with 2 mgl(-1) BA and 0.2 mgl(-1) IAA was found optimum for maximum shoot regeneration (98.33 %) from in vitro leaves with 2-3 longitudinal cuts. Agrobacterium tumefaciens-mediated transformation method was used for generating transgenic B. monniera plants. Putative transformants were confirmed by GUS assay and PCR based confirmation of hptII gene. DNA blot analysis showed single copy insertion of transgene cassette. An average of 87.5 % of the regenerated shoots were found PCR positive for hptII gene and GUS activity was detected in leaves of transgenic shoots at a frequency of 82.5 % The efficient multiple shoots regeneration system described herein may help in mass production of B. monniera plant. Also, the high frequency transformation protocol described here can be used for genetic engineering of B. monniera for enhancement of its pharmaceutically important metabolites.

Isolation and evaluation of cytogenetic effect of Brahmi saponins on cultured human lymphocytes exposed in vitro

Major saponins of Brahmi (Bacopa monniera, Fam: Scrophulariaceae) - bacosides A and B - were isolated from the total methanol extract and characterised based on melting point, TLC, IR, (1)H NMR and (13)C NMR. They were evaluated for their in vitro cytogenetic effects on human peripheral blood lymphocytes by chromosomal aberration (CA) assay and sister chromatid exchange (SCE) assay. The frequency of chromatid type aberrations and reciprocal interchanges between sister chromatids in the treated cells was scored in comparison to the untreated control. At 30 μg/mL dose, bacoside A showed a statistically significant increase in the frequency of both CA and SCE and bacoside B showed an increase only in SCE. Our report of the genotoxicity of the saponins is significant in view of the reports of anticancer activity of Brahmi extracts.

Biochemical characterization of recombinant mevalonate kinase from Bacopa monniera

Mevalonate kinase (MK; ATP: mevalonate 5-phosphotransferase; EC 2.7.1.36) plays a key role in isoprenoid biosynthetic pathway in plants. MK catalyzes the phosphorylation of mevalonate to form mevalonate-5-phosphate. The recombinant BmMK was cloned and over-expressed in E. coli BL21 (DE3), and purified to homogeneity by affinity chromatography followed by gel filtration. Optimum pH and temperature for forward reaction was found to be 7.0 and 30 °C, respectively. The enzyme was most stable at pH 8 at 25 °C with deactivation rate constant (Kd*) 1.398 × 10(-4) and half life (t1/2) 49 h. pH activity profile of BmMK indicates the involvement of carboxylate ion, histidine, lysine, arginine or aspartic acid at the active site of enzyme. Activity of recombinant BmMK was confirmed by phosphorylation of RS-mevalonate in the presence of Mg(2+), having Km and Vmax 331.9 μM and 719.1 pKat μg(-1), respectively. The values of kcat and kcat/Km for RS-mevalonate were determined to be 143.82 s(-1) and 0.43332 M(-1) s(-1) and kcat and kcat/Km values for ATP were found 150.9 s(-1) and 1.023 M(-1) s(-1). The metal ion studies suggested that BmMK is a metal dependent enzyme and highly active in the presence of MgCl2.

Bacopa monniera selectively attenuates suppressed Superoxide dismutase activity in Diazepam induced amnesic mice

BACKGROUND

Amnesia is characterized by loss of memory that could result from abnormal neuro-chemical homeostasis, genetic predisposition or drug abuse. We earlier reported that B. monniera attenuates diazepam, scopolamine and L-NNA induced amnesia and wanted to test if SOD levels were affected by its administration.

PURPOSE

B. monniera is earlier reported to augment the defense system for oxidative stress by increasing the activities of superoxide dismutase, therefore, we investigated its levels after B. monniera administration in combination with different amnesic agents.

METHODS

We treated mice with amnesic agents such as scopolamine, diazepam, L-NNA and MK 801 either with or without B. monniera.

RESULTS

Diazepam (1.75 mg/kg ip) significantly reduced SOD activity while it was unaltered when Scopolamine (0.1 mg/kg ip), MK 801 (0.17 mg/kg ip) and L-NNA (30 mg/kg ip) were administered. B. monniera significantly attenuated diazepam induced suppression of SOD activity.

CONCLUSION

It is suggested that the mechanism of B. monniera's antiamnesic effect may vary depending on the type of amnesic agent used. However, antioxidant mechanism may be central to evoking the memory enhancing effects of B. monniera against diazepam induced amnesia.

Cytoprotective propensity of Bacopa monniera against hydrogen peroxide induced oxidative damage in neuronal and lung epithelial cells

Hydrogen peroxide (H2O2), a major reactive oxygen species (ROS) produced during oxidative stress, is toxic to the cells. Hence, H2O2 has been extensively used to study the effects of antioxidant and cytoprotective role of phytochemicals. In the present investigation H2O2 was used to induce oxidative stress via ROS production within PC12 and L132 cells. Cytoprotective propensity of Bacopa monniera extract (BME) was confirmed by cell viability assays, ROS estimation, lipid peroxidation, mitochondria membrane potential assay, comet assay followed by gene expression studies of antioxidant enzymes in PC12 and L132 cells treated with H2O2 for 24 h with or without BME pre-treatment. Our results elucidate that BME possesses radical scavenging activity by scavenging 2,2-diphenyl-1-picrylhydrazyl, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid), superoxide radical, and nitric oxide radicals. The IC50 value of BME against these radicals was found to be 226.19, 15.17, 30.07, and 34.55 µg/ml, respectively). The IC50 of BME against ROS, lipid peroxidation and protein carbonylation was found to be 1296.53, 753.22, and 589.04 µg/ml in brain and 1137.08, 1079.65, and 11101.25 µg/ml in lung tissues, respectively. Further cytoprotective potency of the BME ameliorated the mitochondrial and plasma membrane damage induced by H2O2 as evidenced by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and lactate dehydrogenase leakage assays in both PC12 and L132 cells. H2O2 induced cellular, nuclear and mitochondrial membrane damage was restored by BME pre-treatment. H2O2 induced depleted antioxidant status was also replenished by BME pre-treatment. This was confirmed by spectrophotometric analysis, semi-quantitative RT-PCR and western blot studies. These results justify the traditional usage of BME based on its promising antioxidant and cytoprotective property.

Chronic administration of bacopa monniera increases BDNF protein and mRNA expressions: a study in chronic unpredictable stress induced animal model of depression

OBJECTIVE

The present study aimed to investigate whether graded doses of Bacopa Monniera (BM) extract could produce antidepressant-like effects in chronic unpredictable stress (CUS) induced depression in rats and its possible mechanism(s).

METHODS

Rats were subjected to an experimental setting of CUS. The effect of BM extract treatment in CUS-induced depression was examined using behavioral tests including the sucrose consumption, open field test and shuttle box escape test. The mechanism underlying the antidepressant-like action of BM extract was examined by measuring brain-derived neurotrophic factor (BDNF) protein and mRNA expression in brain tissues of CUS-exposed rats.

RESULTS

Exposure to CUS for 4 weeks caused depression-like behavior in rats, as indicated by significant decreases in sucrose consumption, locomotor activity and escape latency. In addition, it was found that BDNF protein and mRNA levels in the hippocampus and frontal cortex were lower in CUS-treated rats, as compared to controls. Daily administration of the graded doses of BM extract during the 4-week period of CUS significantly suppressed behavioral changes and attenuated the CUS-induced decrease in BDNF protein and mRNA levels in the hippocampus and frontal cortex.

CONCLUSION

The results suggest that BM extract alleviates depression induced by CUS. Present study also confirms that 80-120 mg/kg doses of BM extract have significantly higher antidepressant-like activity.

In vitro evaluation of Bacopa monniera extract and individual constituents on human recombinant monoamine oxidase enzymes

Bacopa monniera is a traditional Ayurvedic medicinal plant that has been used worldwide for its nootropic action. Chemically standardized extract of B. monniera is now available as over the counter herbal remedy to enhance memory in children and adults. Considering the nootropic action of B. monniera, we evaluated the effect of clinically available B. monniera extract and six of B. monniera constituents (bacoside A3, bacopaside I, bacopaside II, bacosaponin C, bacosine, and bacoside A mixture) on recombinant human monoamine oxidase (MAO) enzymes. The effect of B. monniera extract and individual constituents on human recombinant MAO-A and MAO-B enzymes was evaluated using MAO-Glo(TM) assay kit (Promega Corporation, USA), following the instruction manual. IC50 and mode of inhibition were measured for MAO enzymes. Bacopaside I and bacoside A mixture inhibited the MAO-A and MAO-B enzymes. Bacopaside I exhibited mixed mode of inhibition with IC50 and Ki values of 17.08 ± 1.64 and 42.5 ± 3.53 µg/mL, respectively, for MAO-A enzyme. Bacopaside I is the major constituent of B. monniera, which inhibited the MAO-A enzyme selectively.

Attenuation of smoke induced neuronal and physiological changes by bacoside rich extract in Wistar rats via down regulation of HO-1 and iNOS

Bacopa monniera is well known herbal medicine for its neuropharmacological effects. It alleviates variety of disorders including neuronal and physiological changes. Crackers smoke is a potent risk factor that leads to free radical mediated oxidative stress in vivo. The aim of the current study is to evaluate the protective efficacy of B. monniera extract (BME) against crackers smoke induced neuronal and physiological changes via modulating inducible nitric oxide synthase (iNOS) and hemeoxygenase-1 (HO-1) expression in rats. Rats were exposed to smoke for 1h for a period of 3 weeks and consecutively treated with BME at three different dosages (i.e., 10, 20 and 40 mg/kg b.wt.). Our results elucidate that BME treatment ameliorates histopathalogical changes, reactive oxygen species levels, lipid peroxidation, acetylcholine esterase activity and brain neurotransmitter levels to normal. BME supplementation efficiently inhibited HO-1 expression and nitric oxide generation by down-regulating iNOS expression. Smoke induced depletion of antioxidant enzyme status, monoamine oxidase activity was also replenished by BME supplementation. Thus the present study indicates that BME ameliorates various impairments associated with neuronal and physiological changes in rats exposed to crackers smoke by its potent neuromodulatory, antioxidant and adaptogenic propensity.

Molecular characterization and differential expression studies of an oxidosqualene cyclase (OSC) gene of Brahmi (Bacopa monniera)

Triterpenoid saponins are the class of secondary metabolites, synthesized via isoprenoid pathway. Oxidosqualene cyclases (OSCs) catalyzes the cyclization of 2, 3-oxidosqualene to various triterpene skeletons, the first committed step in triterpenoid biosynthesis. A full-length oxidosqualene cyclase cDNA from Bacopa monniera (BmOSC) was isolated and characterized. The open reading frame (ORF) of BmOSC consists of 2,292 bp, encoding 764 amino acid residues with an apparent molecular mass of 87.62 kDa and theoretical pI 6.21. It contained four QxxxxxW motifs, one Asp-Cys-Thr-Ala-Glu (DCTAE) motif which is highly conserved among the triterpene synthases and another MWCYCR motif involved in the formation of triterpenoid skeletons. The deduced amino acid sequence of BmOSC shares 80.5 % & 71.8 % identity and 89.7 % & 83.5 % similarity with Olea europaea mixed amyrin synthase and Panax notoginseng dammarenediol synthase respectively. Phylogenetic analysis revealed that BmOSC is closely related with other plant OSCs. Quantitative real-time PCR (qRT-PCR) data showed that BmOSC is expressed in all tissues examined with higher expression in stem and leaves as compared to roots and floral parts.

Calcium antagonistic activity of Bacopa monniera in guinea-pig trachea

OBJECTIVE

To demonstrate the calcium antagonistic property of ethanol extract of Bacopa monniera in guinea-pig trachea.

MATERIALS AND METHODS

The dose response curves of CaCl(2) (1 × 10(-5) to 1 × 10(-1) M) were constructed in the absence and presence of ethanol extract of Bacopa monniera (100, 500 and 700 μg/ml) or nifedipine (1 × 10(-6) M) in guinea-pig trachea in calcium free high K(+)-MOPS-PSS (3-(N-morpholino)-propanesulphonic acid physiological salt solution). The data was analyzed by ANOVA followed by least significant difference test or by Student's 't' test for unequal variance when appropriate. A probability of at least P < 0.05 was considered statistically significant.

RESULTS

The plant extract (500 and 700 μg/ml) significantly (P < 0.05) depressed and shifted the calcium concentration-response curves (1 × 10(-3)- 1 × 10(-1) M) to rightward similar to that of nifedipine.

CONCLUSIONS

Bacopa monniera extract exhibited calcium channel blocking activity in guinea-pig tracheal smooth muscles that may rationalize its relaxant action on guinea-pig trachea and its traditional use in respiratory disorders.

Exploring the possible mechanisms of action behind the antinociceptive activity of Bacopa monniera

AIM

Earlier studies have demonstrated that Bacopa monniera (BM), a plant described in Ayurveda for many CNS actions was found to exhibit antidepressant (methanolic extract at 20mg/kg and 40mg/kg p.o.) as well as antinociceptive activity (aqueous extract (AE) at 80 mg/kg, 120 mg/kg and 160 mg/kg p.o.). The present study sought to explore the possible mechanisms of antinociceptive effects of aqueous extract of Bacopa monniera (AEBM) at 80 mg/kg, 120 mg/kg and 160 mg/kg given orally.

MATERIALS AND METHODS

AEBM was given singly as well as with selective α2 receptor blocker Yohimbine, selective β1 receptor blocker Atenolol, serotonin receptor antagonist Cyproheptadine and a non-selective opioid receptor antagonist naloxone in experimental groups of mice and rats under strict protocols and conditions.

RESULTS

We observed that the antinociceptive effects of AEBM in the acetic acid writhing test was prevented by prior treatment with the selective Yohimbine (1 mg/kg, i.p; 14.50 ± 2.26 and 37.17 ± 2.14 writhes in the AEBM-treated and yohimbine pre-treated AEBM groups, respectively) and selective β1 Atenolol receptor blocker (1 mg/kg, i.p; 14.50 ± 2.26 and 31.00 ± 5.44 writhes in the AEBM-treated and yohimbine pre-treated AEBM groups, respectively). In the formalin test, the reduction in licking time with AEBM was found to be reversed by prior treatment with serotonin receptor antagonist Cyproheptadine (1 mg/kg, i.p; 47.33 ± 2.25s and 113.50 ± 3.83s (during phase I i.e. 0-5 min) and 26.67 ± 3.83s and 88.17 ± 7.27s (during phase II i.e. 20-30 min) in the AEBM-treated and Cyproheptadine pre-treated AEBM groups, respectively). The % increase in tail flick latency with AEBM was prevented by prior treatment with the non-selective opioid receptor antagonist naloxone (2mg/kg, i.p; 282.35 and 107.35 in the AEBM-treated and naloxone-treated groups, respectively).

CONCLUSIONS

Our results indicate, that the endogenous adrenergic, serotonergic and opioidergic systems are involved in the analgesic mechanism of action of the aqueous extract of Bacopa monniera.

Root endophyte Piriformospora indica DSM 11827 alters plant morphology, enhances biomass and antioxidant activity of medicinal plant Bacopa monniera

Unorganized collections and over exploitation of naturally occurring medicinal plant Bacopa monniera is leading to rapid depletion of germplasm and is posing a great threat to its survival in natural habitats. The species has already been listed in the list of highly threatened plants of India. This calls for micropropagation based multiplication of potential accessions and understanding of their mycorrhizal associations for obtaining plants with enhanced secondary metabolite contents. The co-cultivation of B. monniera with axenically cultivated root endophyte Piriformospora indica resulted in growth promotion, increase in bacoside content, antioxidant activity and nuclear hypertrophy of this medicinal plant.

Molecular characterization of farnesyl pyrophosphate synthase from Bacopa monniera by comparative modeling and docking studies

Farnesyl pyrophosphate synthase (FPS; EC 2.5.1.10) is a key enzyme in isoprenoid biosynthetic pathway and provides precursors for the biosynthesis of various pharmaceutically important metabolites. It catalyzes head to tail condensation of two isopentenyl pyrophosphate molecules with dimethylallyl pyrophosphate to form C15 compound farnesyl pyrophosphate. Recent studies have confirmed FPS as a molecular target of bisphosphonates for drug development against bone diseases as well as pathogens. Although large numbers of FPSs from different sources are known, very few protein structures have been reported till date. In the present study, FPS gene from medicinal plant Bacopa monniera (BmFPS) was characterized by comparative modeling and docking. Multiple sequence alignment showed two highly conserved aspartate rich motifs FARM and SARM (DDXXD). The 3-D model of BmFPS was generated based on structurally resolved FPS crystal information of Gallus gallus. The generated models were validated by various bioinformatics tools and the final model contained only α-helices and coils. Further, docking studies of modeled BmFPS with substrates and inhibitors were performed to understand the protein ligand interactions. The two Asp residues from FARM (Asp100 and Asp104) as well as Asp171, Lys197 and Lys262 were found to be important for catalytic activity. Interaction of nitrogen containing bisphosphonates (risedronate, alendronate, zoledronate and pamidronate) with modeled BmFPS showed competitive inhibition; where, apart from Asp (100, 104 and 171), Thr175 played an important role. The results presented here could be useful for designing of mutants for isoprenoid biosynthetic pathway engineering well as more effective drugs against osteoporosis and human pathogens.

ABBREVIATIONS

IPP - Isopentenyl Pyrophosphate, DMAPP - Dimethylallyl Pyrophosphate, GPP - Geranyl Pyrophosphate, FPP - FPPFarnesyl Pyrophosphate, DOPE - Discrete Optimized Protein Energy, BmFPS - Bacopa monniera Farnesyl Pyrophosphate Synthase, RMSD - Root Mean square Deviation, OPLS-AA - Optimized Potentials for Liquid Simulations- All Atom, FARM - First Aspartate Rich Motif, SARM - Second Aspartate Rich Motif.

Protective effect ofBacopa monniera L. on cytarabine induced biochemical changes in chick embryo

Bacopa monniera, a medicinal plant distributed throughout India. Cytosine arabinoside (1-β-arabinofuranosylcytosine; Ara-C) is the most important antimetabolite chemotherapeutic drug used for acute leukemia. In this study we examined the chemoprotective property of an ethanolic extract of Bacopa monniera on biochemical changes in chick embryo. CA caused biochemical changes in a concentration and time dependent manner in amniotic fluid, liver and heart tissues. Ethanolic extract of BM given to chick embryo at doses of 2, 4, 6 mg per egg. There is significant decrease in biochemical levels of glucose, protein, urea, uric acid, creatinine and inorganic phosphorus. Enzymatic activities of alkaline phosphatase, lactate dehydrogenase, serum glutamate oxaloacetate transaminase, serum glutamate pyruvate transaminase and malatedehydrogenase were also decreased with dose dependent manner in amniotic fluid, liver and heart tissues.

Randomized controlled trial of standardized Bacopa monniera extract in age-associated memory impairment

BACKGROUND

Brahmi (Bacopa monniera) is a traditional Indian medicinal plant which causes multiple effects on the central nervous system. The standardized extract of this plant has shown enhanced behavioural learning in preclinical studies and enhanced information processing in healthy volunteers.

AIM

To study the efficacy of standardized Bacopa monniera extract (SBME) in subjects with age-associated memory impairment (AAMI) without any evidence of dementia or psychiatric disorder.

METHODS

A double-blind, placebo-controlled randomized study design was employed. The subjects received either 125 mg of SBME or placebo twice a day for a period of 12 weeks followed by a placebo period of another 4 weeks (total duration of the trial 16 weeks). Each subject was evaluated for cognition on a battery of tests comprising mental control, logical memory, digit forward, digit backward, visual reproduction and paired associate learning.

RESULTS

SBME produced significant improvement on mental control, logical memory and paired associated learning during the 12-week drug therapy.

CONCLUSION

SBME is efficacious in subjects with age-associated memory impairment.