Using Glycosylated Hemoglobin and Heat Shock Protein 70 as Thermal Biomarkers in North American Pikas (Ochotona princeps)

Abstract

Pikas (Ochotona princeps), high altitude lagomorphs, are potentially one of the first mammals to be directly affected by global warming. Population decline has been observed in pika populations in Nevada and California. The cause of their decline is unknown but several studies suggest that heat stress, especially at lower altitudes, is a contributing factor. In Montana, populations are potentially stressed in the same way. One hypothesis is that direct thermal stress is causing population decline. This study looks at heat shock protein 70 (HSP70) and glycosylated hemoglobin levels in high and low altitude pika populations as biomarkers for thermal stress. Pikas were trapped from Gold Creek (1962m) and Vista Point (2832m) Montana. Blood was extracted and separated into plasma and packed blood cells. ELISA high sensitivity tests were used for HSP70 quantification. Chromatography techniques, using manimophenylboronic beaded gels, were used to measure the percent of glycosylated hemoglobin. A strong positive correlation was observed between HSP70 levels and weekly average temperatures prior to capture. Due to the inconsistent nature of the glycosylated hemoglobin results, these assays are unable to support oxidative stress as a factor caused by direct thermal stress. Future work includes attaining a larger sample size, locating more trapping sites, further temperature data collection, and refining techniques to assay for glycosylated hemoglobin before definitive conclusions can be made.