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bioRxiv · 10.1101/050476

Ayurvedic Amalaki Rasayana promotes improved stress tolerance and thus has anti-aging effects in Drosophila melanogaster

Abstract

Ethnopharmacological relevanceAmalaki Rasayana (AR) is a common Ayurvedic herbal formulation of Phyllanthus emblica fruits and other ingredients and is used for general good health and healthy aging. We earlier reported it to improve life history traits and to suppress neurodegeneration as well as induced apoptosis in Drosophila.\n\nAim of the studyTo examine effects of dietary AR supplement on cell stress responses in Drosophila melanogaster.\n\nMaterials and methodsLarvae/flies, reared on normal food or on that supplemented with 0.5% (w/v) AR, were exposed to crowding, thermal or oxidative stress and examined for survival, stress tolerance and levels of lipid peroxides, SOD and HSPs.\n\nResultsWild type larvae/flies reared on AR supplemented food survived the various cell stresses much better than those reared on normal food. AR-fed mutant park13 or DJ-1{beta}Delta93 (Parkinsons disease model) larvae, however, showed only partial or no protection, respectively, against paraquat-induced oxidative stress, indicating essentiality of DJ-1{beta} for AR mediated oxidative stress tolerance. AR feeding reduced the accumulation of reactive oxygen species (ROS) and lipid peroxidation even in aged (35 day old) wild type flies while enhancing superoxide dismutase (SOD) activity. We show for the first time that while Hsp70 or Hsp83 expression under normal or stress conditions was not differentially affected by AR feeding, Hsp27 levels were elevated in AR fed wild type control as well as heat shocked larvae. Therefore, besides the known anti-oxidant activity of Phyllanthus emblica fruits, dietary AR also enhances cellular levels of Hsp27.\n\nConclusionIn the context of the reported \"anti-aging\" and \"healthy-aging\" effects of AR, the present in vivo study on a model organisms shows that AR feeding significantly improves tolerance to a variety of cell stresses through reduced ROS and lipid peroxidation and enhanced SOD activity and Hsp27. Such improved cellular defences following dietary AR provide better homeostasis and thereby improve the life-span and quality of organisms life.\n\nO_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=92 SRC=\"FIGDIR/small/050476_figu1.gif\" ALT=\"Figure 1\">\nView larger version (36K):\norg.highwire.dtl.DTLVardef@4452a8org.highwire.dtl.DTLVardef@18eb595org.highwire.dtl.DTLVardef@33533aorg.highwire.dtl.DTLVardef@19d4590_HPS_FORMAT_FIGEXP M_FIG C_FIG

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BibTeXRIS

Vibha Dwivedi, Subhash C. Lakhotia. 2016-04-26. Ayurvedic Amalaki Rasayana promotes improved stress tolerance and thus has anti-aging effects in Drosophila melanogaster. https://doi.org/10.1101/050476

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