title: Effects of plant extracts on the reversal of glucose-induced impairment of stress-resistance in Caenorhabditis elegans.
abstract: Enhanced blood glucose levels are a hallmark of diabetes and are associated with diabetic complications and a reduction of lifespan. In order to search for plant extracts that display preventive activities in such a scenario, we tested 16 extracts used in human nutrition for their survival enhancing activities in the nematode Caenorhabditis elegans. Nematodes were exposed for 48 h to 10 mM glucose in the absence or presence of 0.1% extract. Thereafter, survival was measured at 37 °C. Extracts made from coffee, kola, rooibos and cinnamon, did not influence the glucose-induced reduction of survival. Those made from ginseng, camomile, lime blossom, paraguay tea, balm, rhodiola, black tea, or knotgrass all extended the lifespan of the glucose-treated nematodes significantly but did not rescue survival completely. Extracts from the leaves of blackberries, from hibiscus, elderberries, or jiaogulan completely countered the glucose-induced survival reduction. A potent activation of the proteasome was shown for the most preventive extracts suggesting a more efficient degradation of proteins impaired by glucose. In conclusion, we present a simple animal model to screen for plant extracts with potency to reverse glucose toxicity. Extracts from blackberry leaves, hibiscus, elderberries, and jiaogulan were identified as very potent in this regard whose exact mechanisms of action appear worthwile to investigate at the molecular level.
authors.affiliation: Molecular Nutrition Research, Interdisciplinary Research Center, Justus-Liebig-University of Giessen, Heinrich-Buff-Ring 26-32, 35392, Giessen, Germany.
authors.forename: Elena
authors.initials: E
authors.lastname: Fitzenberger
authors.forename: Dorothé Jenni
authors.initials: DJ
authors.lastname: Deusing
authors.forename: Anette
authors.initials: A
authors.lastname: Wittkop
authors.forename: Adolf
authors.initials: A
authors.lastname: Kler
authors.forename: Erwin
authors.initials: E
authors.lastname: Kriesl
authors.forename: Bernd
authors.initials: B
authors.lastname: Bonnländer
authors.forename: Uwe
authors.initials: U
authors.lastname: Wenzel
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans; D003920:Diabetes Mellitus / Q000378:metabolism; D004195:Disease Models, Animal; D005947:Glucose / Q000009:adverse effects* / Q000378:metabolism; D019684:Magnoliopsida; D010936:Plant Extracts / Q000494:pharmacology*; D046988:Proteasome Endopeptidase Complex / Q000378:metabolism*; D059748:Proteolysis
chemical_list: D010936:Plant Extracts; D046988:Proteasome Endopeptidase Complex; D005947:Glucose