Neuroprotection and antioxidative effects of Sijunzi Tang Decoction in the nematode Caenorhabditis elegans

Abstract

IntroductionKnowledge about the pharmacological properties of traditional TCM formulas is scarce as is their impact on aging. This study evaluated the potential effects of Sijunzi Tang Decoction (SJZTD), Si-Wu-Tang Decoction (SWTD), and Liuwei Dihuang Decoction (LWDHD) against oxidative stress and glucotoxic stress-induced neuronal dysfunction and lifespan reduction. MethodsNematodes (C. elegans) were cultivated under 10mmol/L paraquat or 400mmol/L glucose to assess the protective effects of a systemic Traditional Chinese Medicine (TCM) treatment. Lifespan was determined by calculation of Kaplan-Meier survival curves, formation of reactive oxygen species was quantified by hydroethidine staining, and neuronal functions were evaluated by worm tracking analysis. ResultsA 10% SJZTD solution largely normalized nematode survival under both oxidative stress (increased 3-day-survival rate by 143%) and glucotoxic stress (extended mean lifespan from 19.90 to 23.71 days). Under high glucose conditions we demonstrated both antioxidative effects (reduced Reactive Oxygen Species (ROS) formation by 71%) and neuroprotective effects (improved whole nematode motility by 179%). SWTD and LWDHD failed to confer protection in our model system. ConclusionsThe neuroprotective effects for SJZT decoction against glucotoxic stress due to pronounced antioxidant properties were demonstrated. Future studies should be extended to protection of the neurovascular system in higher organisms.