The following is a summary of “Urine Exosomes Proteomics for Parenchymal Kidney Health in Heart Failure Patients With Mechanical Circulatory Support,” published in the November 2023 issue of Cardiology by Mondal et al.

In heart failure (HF) patients with left ventricular assist device (LVAD)  support, kidney health is often compromised, impacting outcomes, but the direct impact of LVAD on kidney tissue remains unclear.

Researchers conducted a retrospective study to explore the feasibility of using urine exosome proteomics as a non-invasive tool for gauging parenchymal kidney health in LVAD recipients.

They gathered urine samples from 33 patients undergoing LVAD (HeartMate III) surgery (January 2022 to February 2023). Exosomes isolated from preoperative and postoperative day 7 samples underwent untargeted proteomics using LC-MS/MS and iBAQ quantification, focusing on identifying and examining kidney-enhanced proteins.

The results showed exosome authenticity through canonical proteins (CD63, Hsp70) and TEM imaging, with 82.7% falling within the 51-120 nm size range. A total of 7,000 stringent genes yielded an average of 1,150 proteins. Exosomes dominated the primary cellular compartment in GO analysis. Among 176 kidney-enhanced proteins, >50% were consistently present. Differential expression analysis identified 8 proteins with increased expression on the 7th postoperative day, with FDR<0.1. The top 2 proteins were glutathione peroxidase 3 (GPX3, log2 FC 3.4 [95%CI 2.1-4.8]) and fatty acid binding protein 3 (FABP3, log2 FC 2.9 [95%CI 1.7-4.2]). Enrichment analysis highlighted pathway changes indicative of inflammatory and ischemic kidney damage, metabolic dysfunction, and fibrotic transformation, aligning with kidney stress from advanced HF and cardiac surgery.

They concluded that exosomes in urine proved promising for non-invasive kidney assessment in LVAD patients, warranting larger follow-up studies.

Source: ahajournals.org/doi/10.1161/circ.148.suppl_1.17326