Assessment of Sialylation in Skeletal Muscles of a Ground-Based Rat Model of Microgravity
Start Date
April 2025
Location
3rd floor - Library
Abstract
Muscle atrophy is a common issue for astronauts during spaceflight due to prolonged exposure to microgravity. These conditions affect muscle mass and strength, and while exercise helps combat atrophy, it is not entirely sufficient. One method being explored to counter this is the addition of sialic acid. Sialic acid (SA) is a terminal glycan attached to skeletal muscle cells. It helps with fusion and regeneration. Preliminary data shows that sialic acid depletion leads to muscle atrophy in conditions such as GNE myopathy and microgravity. Sialyltransferases (STs) add sialic acid to muscles while sialidases remove it. In this experiment, we aim to assess specific sialic acid linkages and the expression of STs and sialidases in a ground-based rodent model of microgravity. Wistar rats were subjected to hind limb suspension (HLS), which mimics microgravity. Meanwhile, a second group was subject to normal loading which acted as a control. Semiquantitative real-time polymerase chain reaction (qRT-PCR), was used to quantify RNA, and measured the relative gene expression of STs and sialidases. Western blot analysis compared STs and sialidases between the simulated microgravity and control groups. The same muscle tissues also underwent staining with the lectins PNA, WGA, MAA, and SNA, which bind to sialic acids or the underlying glycan chain. Mean fluorescence was quantified and normalized to the average cross-sectional area of muscle fibers. Findings from this study may help identify therapies to help astronauts maintain muscle mass in space.
Assessment of Sialylation in Skeletal Muscles of a Ground-Based Rat Model of Microgravity
3rd floor - Library
Muscle atrophy is a common issue for astronauts during spaceflight due to prolonged exposure to microgravity. These conditions affect muscle mass and strength, and while exercise helps combat atrophy, it is not entirely sufficient. One method being explored to counter this is the addition of sialic acid. Sialic acid (SA) is a terminal glycan attached to skeletal muscle cells. It helps with fusion and regeneration. Preliminary data shows that sialic acid depletion leads to muscle atrophy in conditions such as GNE myopathy and microgravity. Sialyltransferases (STs) add sialic acid to muscles while sialidases remove it. In this experiment, we aim to assess specific sialic acid linkages and the expression of STs and sialidases in a ground-based rodent model of microgravity. Wistar rats were subjected to hind limb suspension (HLS), which mimics microgravity. Meanwhile, a second group was subject to normal loading which acted as a control. Semiquantitative real-time polymerase chain reaction (qRT-PCR), was used to quantify RNA, and measured the relative gene expression of STs and sialidases. Western blot analysis compared STs and sialidases between the simulated microgravity and control groups. The same muscle tissues also underwent staining with the lectins PNA, WGA, MAA, and SNA, which bind to sialic acids or the underlying glycan chain. Mean fluorescence was quantified and normalized to the average cross-sectional area of muscle fibers. Findings from this study may help identify therapies to help astronauts maintain muscle mass in space.
