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Biology subjects

Kavurma, M. M.

Publications and source records attributed to Kavurma, M. M..

2 recordsLinked to original sources

Patient-specific "Physical Twin" artery-on-chip platform reveals complex flow-dependent VWF mechanobiology and guides personalized antithrombotic therapy

Ischemic stroke triggered by carotid atherosclerosis remains unpredictable because the thrombosis embolization is governed by patient-specific vascular geometry and hemodynamics that cannot be recapitulated in conventional models. Here, we engineered "Physical Twin" artery-on-chip platforms that reproduce individualized carotid anatomy with humanized subendothelial matrix composition and arterial endothelial phenotype under physiological flow patterns. We then established thrombotic microenvironments following laser-induced injury. Computational fluid dynamics-guided experiments across distinct patient geometries reveal that local shear dictates a mechanobiological hierarchy: high-shear bifurcations ([~]3,000 s-{superscript 1}) produce von Willebrand factor (VWF) A1-dependent thrombi suppressible by conformationally sensitive inhibitors, whereas low-shear stenoses generate fragile aggregates where VWF-integrin IIb{beta} coupling governs embolization overgrowth. Pulsatile flow suppresses thrombotic growth independent of mean shear. Molecular dynamics simulations reveal why conformationally sensitive nanobodies (caplacizumab) outperform shear-independent aptamers (ARC1172) in high-shear bifurcation flow zones. This Physical Twin platform provides a mechanistic blueprint for geometry-informed, personalized antithrombotic therapy selection.

bioengineering↗

Mitochondrial Dysfunction in Endothelial Cells Drives Greater Vascular Impairment in Females with Diabetes-Associated Peripheral Artery Disease

BackgroundWomen with peripheral artery disease (PAD) experience poorer clinical outcomes than men, particularly in the setting of diabetes. However, the mechanistic basis for these sex- specific disparities remains unclear. MethodsHere, we investigated endothelial cell (EC) function(s) in diabetes-associated PAD, with a focus on sex differences. Limb tissues from patients with diabetes and chronic limb-threatening ischemia (CLTI) undergoing amputation, and a diabetes mouse model of hindlimb ischemia (HLI), were assessed for vasodilatory capacity, angiogenesis, oxidative stress and changes to expression of mitochondrial complex genes. ECs exposed to a hyperglycemic environment in vitro were assessed for mitochondrial function. The therapeutic potential of the mitochondrial-targeted antioxidant MitoQ was investigated. ResultsECs from females with diabetes-associated PAD have altered responses compared to males. Specifically, limb vessels and skeletal muscle from females exhibit reduced arterial relaxation, angiogenesis and increased oxidative stress in response to HLI in mice, and in tissues from patients. Single-cell RNA sequencing of murine limbs revealed marked suppression of EC mitochondrial complex genes in females with diabetes. Female human ECs exposed to high glucose had reduced respiration, reduced expression of mitochondrial genes and increased oxidative stress. Remarkably, MitoQ restored arterial relaxation and the angiogenic response in female diabetes- associated PAD. ConclusionOur findings uncover a striking sex-specific vulnerability involving oxidative stress and mitochondrial dysfunction in EC health in diabetes-associated PAD. These results highlight the need for sex-specific therapeutic strategies in diabetic PAD, which might include mitochondrial targeted antioxidant strategies.

pathology↗