[
International Worm Meeting,
2017]
Animal models of vitamin B12 deficiency have been proven to be difficult due to the storage of the vitamin and the need to maintain animals on deficient diet for extended periods. C. elegans has emerged recently as a suitable alternative due to its short lifespan. C. elegans show signs of B12 deficiency including poor growth rate, low fertility and a shortened lifespan when fed E. coli of low B12 content for five successive generations. However, bacterial diets can impose confounding effects on treatments as they modify nutrients by their metabolism. Aim of the present study was to investigate the effects of vitamin B12 deficiency under axenic conditions to avoid the confounding effects of bacteria. Wild type C. elegans (N2) were conditioned to C. elegans Habitation and Reproduction (CeHR) medium for three generations before culturing in either complete or deficient (no added B12) medium for an additional three generations. Fertility of wild type C. elegans (N2) in deficient CeHR declined significantly (P<0.05) by 52%, 74% and 85% in the first, second and third generations respectively compared to complete CeHR. Body length measured at day 2 from L1 of C. elegans maintained in deficient CeHR was reduced by 63%, 70% and 64% in the three subsequent generations compared to complete CeHR. At day 6 from L1, where all the worms attained their maximum body length, worms in deficient CeHR showed 17%, 27% and 38% reduction in the three subsequent generations respectively compared to worms in complete CeHR. Survival of B12 deficient worms was not affected in the first two generations with a significant reduction (P<0.05) of 13% in the third generation. The results show that C. elegans maintained under axenic media of low B12 develop signs of deficiency more rapidly when compared previous reports of deficiency under monoxenic conditions.
[
International Worm Meeting,
2019]
Polyphenols are a class of phytochemicals, abundant in many food plants including tea, cocoa, fruits and sugarcane. Claims of health benefits of consumption of polyphenols in humans include reduced risk of developing cardiovascular disease, type 2 diabetes and increased lifespan, due to their anti-oxidant and anti-inflammatory properties. However, limited evidence exists on the long-term health effects of consumption of polyphenols. The aims of the present study were to investigate the effects of a sugarcane polyphenol extract Polynol TM on growth, fertility and lifespan of the model organism Caenorhabditis elegans. Methods: Wild-type Bristol N2 were cultured in an axenic defined medium encapsulated into liposomes and fed to the worms in a nanoparticle delivery system. Sugarcane polyphenol extract was incorporated into liposomes at 0, 1, 2, 3, 4, and 5 mg /ml. Growth rate, viable egg count and lifespan in each treatment were measured. Results: For the first 24h, the worm growth rate was reduced in the presence of Polynol TM in a dose dependent manner. However, significantly higher growth rates were observed at 48h at all concentrations of Polynol TM . At 72h, higher growth rate was observed at 3, 4, and 5mg/ml Polynol TM . Fertility, measured as viable offspring, was similar at all concentrations of Polynol TM except a significantly higher fertility at 2 mg/ml. Polynol TM extended the lifespan (28 to 52%) of C. elegans at all dosages tested. Conclusion: Sugarcane polyphenols increase overall growth rate, improve fertility and extend lifespan of Caenorhabditis elegans.