Valeriana officinalis attenuates the rotenone-induced toxicity in Drosophila melanogaster

Abstract

In this study, we investigated the potential protective effects of Valeriana officinalis (V. officinalis) against the toxicity induced by rotenone in Drosophila melanogaster (D. melanogaster). Adult wild-type flies were concomitantly exposed to rotenone (500 μM) and V. officinalis aqueous extract (10mg/mL) in the food during 7 days. Rotenone-fed flies had a worse performance in the negative geotaxis assay (i.e. climbing capability) and open-field test (i.e. mobility time) as well as a higher incidence of mortality when compared to control group. V. officinalis treatment offered protection against these detrimental effects of rotenone. In contrast, the decreased number of crossings observed in the flies exposed to rotenone was not modified by V. officinalis. Rotenone toxicity was also associated with a marked decrease on the total-thiol content in the homogenates and cell viability of flies, which were reduced by V. officinalis treatment. Indeed, rotenone exposure caused a significant increase in the mRNA expression of antioxidant enzymes superoxide dismutase (SOD) and catalase (CAT) and also in the tyrosine hydroxylase (TH) gene. The expression of SOD and CAT mRNAs was normalized by V. officinalis treatment. Our results suggest that V. officinalis extract was effective in reducing the toxicity induced by rotenone in D. melanogaster as well as confirm the utility of this model to investigate potential therapeutic strategies on movement disorders, including Parkinson disease (PD).

Standardized extract of Withania somnifera (Ashwagandha) markedly offsets rotenone-induced locomotor deficits, oxidative impairments and neurotoxicity in Drosophila melanogaster

“…induction of a temporal and concentration dependent locomotor phenotype (as evident by significant impaired climbing ability). These data are consistent with findings of several other researchers (Sudati et al 2013;Laurent et al 2013) and our findings in the fly model (Girish and Muralidhara, 2012). Interestingly, we demonstrate substantial improvement of ROT-induced early mortality as well as locomotor impairment with WS -enrichment.…”

“…In recent times, Drosophila system is extensively employed not only to obtain basic mechanistic data on the pathophysiology of several neurodegenerative diseases, but also as a primary platform to screen various putative phytochemicals for their neuromodulatory potency against experimentallyinduced neurodegeneration (Laurent et al 2013;Sudati et al 2013). Rotenone (ROT), a well-established mitochondrial toxin is often used as a model chemical, since it reproduces some important aspects of PD pathology both in Drosophila and rodent models (Coulom and Birman, 2004;Canon and Greenamyere 2010).…”

“…Exposure of flies to sub-lethal concentrations of ROT in the medium over 7 days has been demonstrated to result in a concentration-related locomotor dysfunction, specific dopaminergic neuronal loss and depletion in dopamine levels in adult flies (Coulom and Birman 2004). Subsequently this system has been widely employed to screen and assess a large number of therapeutic drugs and plant extracts (Chaudhuri et al 2007;Sudati et al 2013). We have also recapitulated these characteristic features of PD in the wild Drosophila melanogaster strains in our laboratory (Hosamani and Muralidhara 2009;.…”

“…The selection criteria was based on our previous findings (Hosamani and Muralidhara 2009;. Several workers have also employed similar concentrations of ROT in their studies in Drosophila system (Saini et al 2010;Sudati et al 2013). Flies were regularly monitored for lethality, and locomotor phenotype (negative geotaxis assay).…”

Valeriana officinalis and melatonin: Evaluation of the effects in Drosophila melanogaster rapid iterative negative geotaxis (RING) test

“…These flies were grown in standard food medium for D. melanogaster containing 1, 2.5, 5 and 10 mg/ml VoE, 8 mM ME or a combination of both 8 mM ME + 10 mg/ml VoE. The choice of V. officinalis aqueous extract concentrations was based on previous observations by Sudati et al (2013) which showed that V. officinalis aqueous extracts in the range of 5 -20 mg/ml did not cause overt signals of toxicity in flies. Coulom and Birman (2004) showed that a 5 mM concentration of the antioxidant melatonin was able to prevent both locomotor deficits and neuron degeneration in Drosophila.…”