<b>High-Frequency Murine Ultrasound of the Cardiac Effects of Lactation on Postpartum and Hypertension During Pregnancy and Microrobot Drug Delivery</b>
Creators: name: Meeks, Adalyn Maria Fulun
Publisher: name: Purdue University Graduate School
Year: 2024
Subjects: classificationCode: 400303
subject: Biomechanical engineering
classificationCode: 400304
subject: Biomedical imaging

description: Murine, or small rodent, models can provide valuable and translatable insights into human pathophysiology. Specifically, we are looking to combine murine models and high-frequency ultrasound to non-invasively investigate microrobot drug delivery systems, cardiac effects of lactation on the mother during postpartum, and cardiac remodeling due to the combination of pregnancy and hypertension.Currently, we are looking at the applications of microrobots within the colon to provide targeted treatment for patients suffering from inflammatory bowel disease (IBD). IBD is an overarching term encompassing chronic inflammation of the digestive tract tissue. The standard treatment of IBD includes oral and injectable treatments depending on disease severity. The drawbacks of these therapeutics are the associated systemic toxicity, non-specific treatment allocation, and degradation of the treatment in proximal portions of the gastrointestinal (GI) system. The goal of this research is to use an external magnetic torque to cause the microrobots to tumble to targeted areas of inflammation and release a drug payload. Retroactive locomotion of these microrobots can avoid degradation in the proximal GI tract. Therefore, these microrobots need a smaller drug payload to provide the same efficacy as traditional treatments.The cardiovascular system adapts to meet the growing physiological demands of pregnancy. Although this change has been greatly studied, it is unclear if this change in shape and function returns to prepregnant values during postpartum. Previous research has also shown that lactation affects the mother’s hemodynamics during postpartum, but its impact on cardiac morphology is still not completely understood. To study this further, we longitudinally tracked cardiovascular changes using ultrasound and blood pressure measurements in C57BL6/J mice during pregnancy and postpartum that were either lactating or not.Chronic hypertension affects approximately 1 in 20 pregnancies and its prevalence in pregnancies continues to increase. The maternal cardiovascular system goes through dynamic changes during pregnancy to meet the demands of perfusing the gestation, especially during the exponential growth seen later in pregnancy. Studies with female C57BL6/J mice demonstrate comparable cardiovascular changes during pregnancy to those observed in humans. Additionally, a study using rats showed the cardioprotective properties of pregnancy against angiotensin II-induced fibrosis. The objective of this study is to characterize non-invasive cardiac remodeling in a small animal model of hypertensive disorders in pregnancy. We used a combination of ultrasound imaging and noninvasive blood pressure measurements to longitudinally monitor the physiological adaptations that occur during pregnancy with superimposed hypertension.