Background: The antidepressant Mianserin has been shown to extend the lifespan of Caenorhabditis elegan (C. elegan), a well-established model organism used in ageing research. The extension of lifespan in C. elegan was shown to be dependent on increased expression of the scaffolding protein (ANK3/unc-44). In contrast, antidepressant use in humans is associated with an increased risk of death. The C. elegan elegan in the laboratory are fed Escherichia coli (E. coli), a diet high in protein and low in carbohydrate, whereas a typical human diet is high in carbohydrates. We hypothesized that dietary carbohydrates might mitigate the lifespan-extension effect of mianserin.
Objective: To investigate the effect of glucose added to the diet of C. elegan on the lifespan-extension effect of mianserin.
Methods: Wild-type Bristol N2 and ANK3/unc-44 inactivating mutants were cultured on agar plates containing nematode growth medium and fed E. coli. Treatment groups included (C) control, (M50) 50 μM mianserin, (G) 73 mM glucose, and (M50G) 50 μM mianserin and 73 mM glucose. Lifespan was determined by monitoring the worms until they died. Statistical analysis was performed using the Kaplan-Meier version of the log-rank test.
Results: Mianserin treatment resulted in a 12% increase in lifespan (P<0.05) of wild-type Bristol N2 worms but reduced lifespan by 6% in ANK3/unc-44 mutants, consistent with previous research. The addition of glucose to the diet reduced the lifespan of both strains of worms and abolished the lifespan-extension by mianserin.
Conclusion: The addition of glucose to the diet of C. elegan abolishes the lifespan-extension effects of mianserin.