Guarana (Paullinia cupana Mart.) attenuates methylmercury-induced toxicity in Caenorhabditis elegans

Abstract

The influence of routine guarana (Paullinia cupana) consumption on apparent tolerance to mercury intoxication has been proposed. The present study investigated this hypothesis in Caenorhabditis elegans, a suitable experimental model for studies in toxicology. Wild type (WT) and skn-1 (ok2315) worm strains were pretreated with guarana ethanolic extract (GEE) from larvae 1 (L1) to L4 stage and then exposed for 6 hours to methylmercury (MeHg). The analyses included evaluation of GEE’s effects on lethality, developmental delay, feeding, locomotion, gene expression (sod-3, gst-4, sir-2.1, hsf-1, snn-1, mtl-1, mtl-2, aat-1, aat-2 and aat-3) and antioxidant activity. GEE pre-treatment had no aberrant effects on WT worms exposed to MeHg, and protected skn-1 (ok2315) worms, which are more susceptible to environmental stresses. Protective effects of GEE might be dependent on modulation of genes other than those directly involved in antioxidant activity. GEE increased the expression of genes involved in metal transport (aat-2), metal detoxification (mtl-1 and mtl-2) and antioxidant responses (sir-2.1 and sod-3). Thus, routine consumption of guarana might be beneficial in protecting against MeHg-induced toxicity.

Towards Therapeutic Alternatives for Mercury Neurotoxicity in the Amazon: Unraveling the Pre-Clinical Effects of the Superfruit Açaí (Euterpe oleracea, Mart.) as Juice for Human Consumption

“…Thus, the use of endemic plants is a more realistic alternative for these populations to protect themselves against MeHg-induced neurotoxicity. In recent years, many efforts have been devoted to the analysis of plants used by vulnerable populations in developing countries, such as India or Brazil [20,73,74,75,76,77]. Thus, this work contributes to the need to find alternatives for vulnerable populations exposed to MeHg.…”

“…Moreover, it was hypothesized that the consumption of Amazonian fruits would protect exposed populations, reducing the accumulation of mercury in humans [19]. Despite of that, studies with Amazonian fruits and MeHg intoxication are relatively scarce, being mainly limited to fruits such as guaraná, maná-cubiu, burití and açaí [20,21,22,23,24]. Although guaraná ( Paullinia cupana , Mart.)…”

“…Although guaraná ( Paullinia cupana , Mart.) already demonstrated that promotes the expression of antioxidant genes in C. elegans [20], locomotor improvement in fruit flies [21] and in vitro partial protection against neuroinflammation caused by MeHg [21], no data in mammals is still available. However, maná-cubiu ( Solanum sessiliflorum Dunal), burití ( Mauritia flexuosa L.) and açaí ( Euterpe oleracea , Mart.)…”

Protective Effects ofPlathymenia reticulataandConnarus favosusAqueous Extracts against Cadmium- and Mercury-Induced Toxicities

“…This eventually decreased the intracellular MeHg concentration mediated by the increased concentrations of MRP1 and MRP2 ABC transporters (40–42). Similarly, the Skn1 transcription factor, which is the homolog of the mammalian Nrf2 in Caenorhabditis elegans , is involved in the resistance of this nematode worm to MeHg, and the ethanolic extract of the guarana plant was shown to protect skn-1 -mutated nematodes against MeHg (43). MeHg also increased Nrf2 activation by the downregulation of the Fyn kinase.…”

Antioxidant protection by β‐selenoamines against thioacetamide‐induced oxidative stress and hepatotoxicity in mice

“…Here, we investigated the protective properties of antioxidant compounds, β‐selenoamines, against TAA‐induced oxidative damage. Several studies have shown that antioxidant therapies attenuate the tissue damage caused by oxidative stress . In this regard, we designed our study following previous results from our lab showing that β‐selenoamines presented significant antioxidant properties in vitro and in a Caenorhabditis elegans model …”