Session Information: Moderated by Dr. Jaime Murphy in the Holland-Waller Commons from 10:00-11:15 a.m. on Thursday, April 16th.
Arriona Davis
Using Deoxyribose Assay to Measure Antioxidant Capabilities of Cysteine
Oxidative stress occurs when the body cannot remove reactive oxygen species (ROS) quickly enough, leading to cellular damage. Antioxidants help to prevent this damage. This study examined whether cysteine, a sulfur-containing amino acid, can protect against the highly reactive hydroxyl radical (•OH). Using the deoxyribose assay—which generates hydroxyl radicals and measures how much damage they cause to deoxyribose sugar— different concentrations of cysteine were tested and damage levels measured with a UV-Vis spectrophotometer. Cysteine showed antioxidant activity at lower concentrations, reducing the amount of damage formed in the reaction. However, at higher concentrations, cysteine became less effective and even behaved as a pro-oxidant, likely because it reacted with other chemicals in the assay before it could neutralize the hydroxyl radical. These findings suggest that cysteine does have antioxidant properties, but the deoxyribose assay is not the best assay to test its antioxidant capabilities.
Eva Rogers
Spaceflight Drives Genomic Mutation Through Reactive Oxygen Species and Reveals the Radical-Scavenging Capacity of Antioxidants
Oxidative stress arises when reactive oxygen species (ROS) exceed antioxidant defense. ROS contain unpaired electrons that readily react with and damage biological macromolecules. The overproduction of ROS can cause cancer, cardiovascular disease, and diabetes. Spaceflight is a stressor that contributes to ROS overproduction through elevated levels of radiation, carbon dioxide, and microgravity. When this imbalance occurs, ROS readily oxidizes nucleotides and contributes to somatic mutation. To study the effect of spaceflight-induced oxidative stress on somatic mutation, two mice cohorts were chosen to fly into space or remain on Earth as a control. Upon return to Earth, tissues were sampled from both mice cohorts. Analysis of the RNA-sequencing data found 5-17 fold higher mutation frequencies across tissues of the flight mice relative to the ground controls, with adenine-to-guanine substitutions predominating. This suggested that spaceflight-induced oxidative stress contributed to increased somatic mutation. To combat ROS-induced damage, antioxidants neutralize ROS by donating an electron. My research evaluated the antioxidant potential of 1,3-Dimethylimidazole-2(3H)-thione (DMIT) in neutralizing ROS and thereby preventing deoxyribose damage using a deoxyribose assay. Results found that DMIT helped prevent ROS-induced deoxyribose damage. Future directions include examining whether antioxidant supplementation benefits astronauts experiencing oxidative stress amidst spaceflight.
Emily Smith
Investigating the synthesis and antibacterial activity of a main-chain cationic polymer
Antibiotic resistance is a growing threat to public health. Due to the overuse of antibiotics in agriculture, the overprescription of antibiotics, and the misuse of antibiotics by patients, antibiotic resistance is spreading at an alarming rate. As antibiotic resistance spreads, the antibiotics we depend on to treat common infections become ineffective. Therefore, it is imperative to develop novel treatments for infections that do not increase the prevalence of antibiotic resistance. One treatment being explored is the use of synthetic polymers with antibacterial properties. Through electrospinning, polymers can be used to create wound dressings to promote healing of infected wounds and protect them from the environment. This study shows the successful synthesis of a main-chain cationic polymer that has previously shown promising antibacterial activity. This study shows the successful creation of nanofibers from the polymer using electrospinning and tests the antibacterial activity of the nanofibers on organisms that have the highest risk of developing antibiotic resistance. While this delivery method did not show large effects on bacterial growth, the polymer did exhibit promising effects on several organisms. Further studies should investigate the use of a greater amount of nanofibers or a greater amount of polymer embedded within the nanofibers to improve antibacterial activity.
Information for 