ABS 127: The role of 17𝛽-estradiol on mitochondrial enzyme activity in a murine model of volumetric muscle loss injury

Reese Groover ¹ , Dr. Junwon Heo ¹ , Dr. Jarrod Call ¹

¹ University of Georgia, GA, USA

Van Wickle (2025) Volume 1, ABS 127

Introduction: The objective of this study was to explore the role of estradiol in mitochondrial enzyme activities following volumetric muscle loss (VML) injury. Next, female C57BL/6J mice were divided into three groups: VML+Sham surgery (VML), VML+Ovariectomized (OVX)+Placebo pellets (VML+OVX+Placebo), and VML+OVX+Estradiol (E2) pellets (VML+OVX+E2). At 12 weeks of age, OVX surgery was performed, followed by either placebo or E2 pellets. Two weeks after OVX surgery, unilateral VML surgery was conducted on the hindlimb plantar flexors (gastrocnemius, soleus, plantaris muscles). After 3- and 7- days post VML injury, mitochondrial enzyme activity (e.g., citrate synthase, pyruvate dehydrogenase; PDH, β-3-hydroxyacyl-CoA dehydrogenase; β-HAD) was measured using a spectrophotometer and spectrofluorometer, with results analyzed through a One-Way ANOVA test. There were no differences in CS and PDH across the groups. The VML+OVX+Placebo group has a greater β-HAD compared to the VML+Sham group. In conclusion, while estradiol does not significantly impact citrate synthase or pyruvate dehydrogenase activity following volumetric muscle loss injury, the absence of estradiol following VML injury is associated with increased β-HAD activity, suggesting a potential role of estrogen in modulating mitochondrial fatty acid oxidation.