Janvi Desai
Pronouns: she/her/hers
Research Mentor(s): Scott Leiser
Research Mentor School/College/Department: Molecular and integrative Physiology / Medicine
Program: UROP
Session: Session 4 (1:40pm – 2:30pm)
Authors: Janvi Desai, Ajay Bhat, Rebecca Cox, Scott Leiser
Abstract
Diet can have either a positive or negative impact on healthy aging. For example, in many model systems, dietary restriction increases lifespan, while high glucose diets decrease lifespan. Diet also influences the gut microbiome, which can also have negative or beneficial effects on the host. As an organism ages, it alters both the diversity and the composition of its microbiome. Recent studies demonstrate that microbes have the potential to regulate the longevity of their host. However, it is unknown how microbes adapt to host dietary changes, or whether this microbial adaptation influences the physiology of the host. In this study, we use Caenorhabditis elegans as a model system to understand the effect of diet and microbiome on aging. We employed high glucose as a dietary model known to decrease lifespan in C. elegans. Intake of high glucose can increase the production of reactive oxygen species (ROS), which is a stress for both the host and microbes. With the knowledge that microbes have a shorter generation time and can thus evolve and adapt to stress more quickly, we wondered whether ROS-evolved bacteria can alter the lifespan of their host during high glucose conditions. To test this, we used bacterial strains evolved to resist ROS (OP50-AEP). These strains were generated previously in the Leiser lab through adaptive laboratory evolution experiments where the bacteria has a mutation in the gene encoding the iron-sulfur cluster regulator. By feeding these bacteria to worms in high glucose and measuring their lifespan, we are testing whether this microbial ROS stress resistance leads to protection of the host nematodes. Concurrently, we are conducting adaptive laboratory evolution of bacteria in the presence of high glucose (4% glucose) to generate bacterial strains adapted to grow in high glucose conditions. We will use this newly evolved bacterial strain in a lifespan where worms are in the presence of high glucose to test whether the evolved bacteria benefit the health and longevity of the host in this environment.
