Antistress effects of bacosides of Bacopa monnieri: modulation of Hsp70 expression, superoxide dismutase and cytochrome P450 activity in rat brain

Abstract

The antistress effect of bacosides of Brahmi (Bacopa monnieri, BBM), dissolved in distilled water, was -studied in adult male Sprague Dawley rats by administering oral doses of 20 and 40 mg/kg for 7 consecutive days. In half of the animals treated with 20 or 40 mg/kg of BBM, stress was given 2 h after the last dose. Stress was also administered to the animals treated with distilled water alone. BBM, at both doses, did not induce a significant change in the expression of Hsp70 in any brain region studied while stress alone produced a significant increase in the Hsp70 expression in all the brain regions. A significant decrease in the activity of superoxide dismutase (SOD) was evident in the hippocampus with the lower dose of BBM and in animals given stress alone, while an increase in the activity of SOD was observed in the brain regions with the higher dose of BBM. An increase in the activity of cytochrome P450 (P450) dependent 7-pentoxyresorufin-o-dealkylase (PROD) and 7-ethoxyresorufin-o-deethylase (EROD) was observed in all the brain regions after exposure to stress alone and with both doses of BBM although the magnitude of induction of P450 expression was less with a higher dose of BBM. Interestingly, stress when given to the animals pretreated with BBM for 7 days resulted in a decrease in Hsp70 expression in all the brain regions with a significant decrease occurring only in the hippocampus. Likewise the activity of SOD was found to be further reduced in all the brain regions in the animals treated with the lower dose of BBM followed by stress. However, when stress was given to the animals pretreated with the higher dose of BBM, a significant increase in the enzyme activity was observed in the cerebral cortex and in the rest of the brain while the activity of SOD was reduced to a much greater extent in the cerebellum and in the hippocampus. Likewise, the activity of P450 enzymes was found to be restored to almost control levels in the animals given stress and pretreated with the higher dose of BBM, while a lesser degree of induction, compared with animals treated with BBM or stress alone, was observed in the animals pretreated with the lower dose of BBM and given stress. The data indicate that BBM has potential to modulate the activities of Hsp70, P450 and SOD thereby possibly allowing the brain to be prepared to act under adverse conditions such as stress.

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

“…Bacoside A is a mixture of bacosaponin isomers. These active components facilitate learning and memory and also possess antiamnesic, antistress (Chowdhuri et al 2002), anxiolytic (Ernst 2006), antidementic (Dhawan and Singh 1996), antiulcerogenic, antiarthritis, anti-inflammatory (Channa et al 2006), antifatigue (Anand et al 2012) and neuroprotective properties (Dhanasekharan et al 2007;Pandareesh and Anand 2013). We previously demonstrated the antioxidant and plasmid DNA damage preventive properties of hexane, chloroform, ethyl acetate, acetone, methanol and aqueous extracts from B. monniera (Anand et al 2011).…”

Heat shock response: hsp70 in environmental monitoring

“…Being integrators of diverse aspects of protein damage, Hsp70 may provide added value in environmental risk assessment by complementing the already existing tests that measure more specific modes of toxic action. A few studies in recent years have correlated the expression of hsp70 with known toxicological endpoints [51][52][53]. The efficiency of hsp70 expression as biomarker of environmental pollution has been advocated by many researchers [36,51,[54][55][56][57][58][59].…”

Anti-apoptotic mechanism of Bacoside rich extract against reactive nitrogen species induced activation of iNOS/Bax/caspase 3 mediated apoptosis in L132 cell line

“…Bacoside A is a mixture of bacosaponin isomers. B. monniera possesses anti-fatigue (Anand et al 2012), antiamnesic (Bhattacharya et al 2000), anti-stress (Chowdhuri et al 2002), memory enhancing, anxiolytic (Ernst 2006), anti-ulcerogenic, anti-arthritis, antiinflammatory (Channa et al 2006) and neuroprotective properties (Dhanasekharan et al 2007). In addition, the herb is known to possess good amount of flavonoids and phenolic compounds, which has strong antioxidant property.…”