RESUMEN
Secoisolariciresinol diglucoside (SDG) is a phytoestrogen and rich in food flaxseed, sunflower seeds, and sesame seeds. Among the beneficial pharmacological activities of SDG on health, many are age related, such as anticancer, antidiabetes, antioxidant, and neuroprotective effects. Thus, we investigated if SDG had an effect on antiaging in Caenorhabditis elegans (C. elegans). Our results showed that SDG could extend the lifespan of C. elegans by up to 22.0%, delay age-related decline of body movement, reduce the lethality of heat and oxidative stress, alleviate dopamine neurodegeneration induced by 6-hydroxydopamine (6-OHDA), and decrease the toxicity of Aß protein in C. elegans. SDG could increase the expression of the downstream genes of DAF-16, DAF-12, NHR-80, and HSF-1 at mRNA level. SDG could not extend the lifespan of mutants from genes daf-16, hsf-1, nhr-80, daf-12, glp-1, eat-2, and aak-2. The above results suggested that SDG might enhance the stress resistance, delay the progression of aging-related diseases, and extend the lifespan of C. elegans via DAF-16 and HSF-1.
Asunto(s)
Butileno Glicoles/farmacología , Proteínas de Caenorhabditis elegans/metabolismo , Factores de Transcripción Forkhead/metabolismo , Glucósidos/farmacología , Longevidad/efectos de los fármacos , Factores de Transcripción/metabolismo , Envejecimiento/efectos de los fármacos , Animales , Butileno Glicoles/envenenamiento , Caenorhabditis elegans/efectos de los fármacos , Caenorhabditis elegans/metabolismo , Progresión de la Enfermedad , Glucósidos/envenenamiento , Longevidad/genética , Estrés Oxidativo/efectos de los fármacosRESUMEN
The discovery of new topoisomerase I inhibitors is necessary since most of the antitumor drugs are targeted against type II and only a very few can specifically affect type I. Topoisomerase poisons generate toxic DNA damage by stabilization of the covalent DNA-topoisomerase cleavage complex and some have therapeutic efficacy in human cancer. Two iridoids, aucubin and geniposide, have shown antitumoral activities, but their activity against topoisomerase enzymes has not been tested. Here it was found that both compounds are able to stabilize covalent attachments of the topoisomerase I subunits to DNA at sites of DNA strand breaks, generating cleavage complexes intermediates so being active as poisons of topoisomerase I, but not topoisomerase II. This result points to DNA damage induced by topoisomerase I poisoning as one of the possible mechanisms by which these two iridoids have shown antitumoral activity, increasing interest in their possible use in cancer chemoprevention and therapy.
Asunto(s)
Daño del ADN/efectos de los fármacos , Glucósidos/envenenamiento , Iridoides/envenenamiento , Neoplasias/enzimología , Piranos/envenenamiento , Inhibidores de Topoisomerasa I , Inhibidores de Topoisomerasa II , Camptotecina/farmacología , ADN-Topoisomerasas de Tipo I/química , ADN-Topoisomerasas de Tipo I/metabolismo , ADN-Topoisomerasas de Tipo II/química , ADN-Topoisomerasas de Tipo II/metabolismo , Inhibidores Enzimáticos/farmacología , Humanos , Glucósidos Iridoides , Neoplasias/patología , Células Tumorales CultivadasRESUMEN
A severe outbreak of Emory milkvetch poisoning in cattle and sheep occurred near Roswell, New Mexico, in the spring of 1975. Mortality averaged 2% to 3% and morbidity averaged 15% to 20%. Emory milkvetch collected from the infested area contained miserotoxin measured as 5 to 9 mg of NO2/g of plant (dry weight). Chicks fed extracts of Emory milkvetch showed toxic signs when fed one dose as 300 mg of NO2/kg of body weight, and died within 5 to 8 hours when fed milkvetch as 400 mg of NO2/kg. A sheep fed Emory milkvetch for 7 days in the form of 38 mg of NO2/kg/day developed signs of nitro poisoning on the 7th day. Cattle were poisoned or died when fed Emory milkvetch as 12 to 20 mg of NO2/ig for several days. The toxic signs observed in the field and under experimental conditions were similar.