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Reeves, R. R.

Publications and source records attributed to Reeves, R. R..

3 recordsLinked to original sources

Circulating biomarkers in serum from aortic valve stenosis patients predict sex-specific drug responses in valve myofibroblasts

Aortic valve stenosis (AVS) is a prevalent, sexually dimorphic cardiovascular disease characterized by fibro-calcification of the aortic valve leaflet. Sex differences in AVS arise in part from sexually dimorphic serum composition that differentially regulate valvular interstitial cell (VIC) myofibroblast activation. However, how individual serum factors contribute to sex-specific drug responses targeting VIC myofibroblast activation remains unknown. Here, we integrate serum proteomic profiling with in vitro drug screening using hydrogel biomaterials to identify sex-specific regulators of antifibrotic drug efficacy. We found that Insulin-like Growth Factor Binding Protein 2 (IGFBP2) serum levels are associated with resistance to the antifibrotic drug Evogliptin only in female VICs cultured with female AVS serum. This mechanism is driven by IGFBP2-mediated activation of Rho/ROCK and focal adhesion kinase signaling pathways that counteract Evogliptin treatment. Our findings reveal a sex-specific, serum-mediated mechanism of Evogliptin resistance and highlight IGFBP2 as a candidate biomarker for stratifying female AVS patients for Evogliptin treatment. More broadly, these findings underscore the importance of incorporating sex-stratified biomarker analyses into AVS therapeutic development to improve patient-specific treatment recommendations.

bioengineering↗

Secreted cytokines from inflammatory macrophages modulate sex differences in valvular interstitial cells on hydrogel biomaterials

Patients with aortic valve stenosis (AVS) experience fibrosis and/or calcification in valve tissue, which leads to heart failure if left untreated. Inflammation is a hallmark of AVS and secreted cytokines from pro-inflammatory macrophages are thought to contribute to valve fibro-calcification by driving the activation of valvular interstitial cells (VICs) to myofibroblasts. However, the molecular mechanisms by which inflammatory cytokines differentially regulate myofibroblast activation as a function of biological sex are not fully defined. Here, we developed an in vitro hydrogel culture platform to culture male and female valvular interstitial cells (VICs) and characterize the sex-specific effects of inflammatory cytokines on VIC activation to myofibroblasts and osteoblast-like cells. Our data reveal that tumor necrosis factor alpha (TNF-) modulates female-specific myofibroblast activation via MAPK/ERK signaling, nuclear chromatin availability, and osteoblast-like differentiation via RUNX2 nuclear localization. Collectively, hydrogel biomaterials as cell culture platforms are critical for distinguishing sex differences in cellular phenotypes.

bioengineering↗

A New Form of Decellularized Extracellular Matrix Hydrogel for Treating Ischemic Tissue via Intravascular Infusion

Biomaterials, such as extracellular matrix (ECM) hydrogels, have been widely used in preclinical studies as injectable tissue engineering therapies; however, injectable therapies are limited as they can cause localized trauma or organ perforation. We have developed a new ECM therapy, the low molecular weight fraction derived from decellularized, digested ECM, for intravascular infusion. This new form of ECM can be infused after injury, specifically localize to injured tissues by coating the leaky microvasculature, and promote cell survival and tissue repair. In this study, we show the feasibility and targeting of intravascular ECM infusions using models of acute myocardial infarction (MI), traumatic brain injury, and pulmonary arterial hypertension. Furthermore, safety and efficacy were demonstrated in small and large animal models of acute MI following intracoronary infusion, which included using a clinically-relevant catheter in the large animal model. Functional improvements, specifically reduced left ventricular volumes and improved wall motion scores were observed after ECM infusions post-MI. Genes related to tissue repair and inflammation were differential expressed in response to ECM infusions. This study shows proof-of-concept for a new paradigm of delivering pro-healing ECM biomaterials via intravascular infusion to heal tissue from the inside out.

bioengineering↗