# Pathophysiology and prevention of degeneration of heterograft biomaterials due to advanced glycation end products and serum protein infiltration > **NIH NIH F31** · UNIVERSITY OF PENNSYLVANIA · 2024 · $48,974 ## Abstract Bioprosthetic heart valves (BHV), fabricated from heterograft biomaterials such as glutaraldehyde-fixed bovine pericardium (BP), are widely used as a replacement for patients who have severe heart valve disease (HVD), which affects millions of people worldwide. Despite being effective, a limitation of BHV fabricated from BP is that they undergo structural valve degeneration (SVD) which limits durability. Although most commonly attributed to calcification, recent research has shown that advanced glycation end products (AGE) and serum protein infiltration also contributes to SVD. AGE mechanisms impair endothelial cell growth and may mechanistically contribute to lack of endothelialization of BHV experimentally and clinically. Many studies to inhibit calcification of BP have been done; however, strategies to mitigate AGE-serum protein accumulation have just begun to be explored. Through our studies we have recently identified, the AGE-inhibitor pyridoxamine (PYR), a vitamin B6 vitamer, to be a leading model compound that is effective in significantly reducing AGE accumulation and serum protein uptake of BP both in vitro and in vivo in rat subdermal implant studies. Furthermore, we have also established an innovative modification of BP with Poly-2-methyl-2- oxazoline (POZ), which significantly reduced serum protein uptake both in vitro and in rat subdermal explants. The central hypothesis of both my dissertation and this proposal is: Pretreatment of BP with PYR and POZ can mitigate AGE and serum protein pathophysiology that contributes to noncalcific SVD mechanisms. Ethanol (EtOH) pretreatment of BP, an FDA approved anti-calcification methodology, will be a mechanistically based experimental intervention in my study design, that will help explore the interactions between calcific and non- calcific SVD mechanisms. Aim 1: Investigate in vitro the mechanism and efficacy of inhibition of AGE and serum protein infiltration to enhance heterograft biocompatibility by studying endothelial cell-BP interactions. Subaim 1a: Evaluate the effects of PYR pretreatment of BP to mitigate AGE and serum protein mechanisms: blood outgrowth endothelial cell (BOEC) culture studies with high shear flow simulation. Subaim 1b: To determine the effect of POZ mediated serum protein exclusion on promotion of BOEC adhesion and reduction of endothelial activation. Aim 2: To investigate the mechanism and efficacy of inhibition of AGE and serum protein SVD pathology, and interactions with calcification using rat subdermal BP implants: PYR and POZ studies. Subaim 2a: To study the efficacy of PYR pretreated BP, with or without ethanol pretreatment, on mitigating AGE-serum protein pathophysiology and calcification using a rat subdermal implant model. Subaim 2b: To study the efficacy of POZ alone, and the combined BP pretreatment with PYR, POZ, and ethanol for mitigating AGE, serum protein uptake and calcification in the rat subdermal implant model. The findings from this proposal will... ## Key facts - **NIH application ID:** 10874443 - **Project number:** 5F31HL168909-02 - **Recipient organization:** UNIVERSITY OF PENNSYLVANIA - **Principal Investigator:** Tina Thomas - **Activity code:** F31 (R01, R21, SBIR, etc.) - **Funding institute:** NIH - **Fiscal year:** 2024 - **Award amount:** $48,974 - **Award type:** 5 - **Project period:** 2023-05-01 → 2026-04-30 ## Primary source NIH RePORTER: https://reporter.nih.gov/project-details/10874443 ## Citation > US National Institutes of Health, RePORTER application 10874443, Pathophysiology and prevention of degeneration of heterograft biomaterials due to advanced glycation end products and serum protein infiltration (5F31HL168909-02). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/10874443. Licensed CC0. --- *[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*