Abstract
BackgroundOxygen supplementation, although a cornerstone of emergency and cardiovascular medicine, often results in hyperoxia, a condition characterized by excessive tissue oxygen which results in adverse cardiac remodeling and subsequent injurious effects to physiological function. Cardiac remodeling is further influenced by various risk factors, including pre-existing conditions and sex. Thus, the purpose of this experiment was to investigate cardiac remodeling in Type I Diabetic (Akita) mice subjected to hyperoxic treatment. MethodsMale and female Akita and wild-type (WT) mice were divided into four groups based on gender and treatment, and were then subjected to either FiO2 > 90% (hyperoxia) for 72 h in an airtight chamber or normal air (normoxia). Physical, functional, and electrophysiological parameters were then evaluated. Finally, we employed correlational analysis and Multi-Way Analysis of Variance (ANOVA) which determined hyperoxia to have the greatest statistical influence on cardiac pathophysiology, followed by sex, and finally genotype.ResultsOverall, we demonstrated that Akita mice experience distinct challenges from wild type (WT) mice. Specifically, Akita males at both normoxia and hyperoxia showed significant decreases in body and heart weights, prolonged PR, QRS, and QTc intervals, and reduced %EF and %FS at normoxia compared to WT controls. Moreover, we found Akita males largely resemble female mice (both WT and Akita) with regards to the parameters studied. ConclusionsTaken together, our data suggest that Type I diabetic patients may have distinct cardiac pathophysiology under hyperoxia compared to uncomplicated patients, with males being at high risk. These findings can be used to enhance the provision of care in ICU patients with Type I diabetes as a comorbid condition.