Association between serum fatty acids and microcirculation in kidney transplant recipients

Chronic kidney disease (CKD) is associated with an increased cardiovascular risk, including microvascular complications. Previous studies have shown alterations in the fatty acid profile in kidney transplant (KT) recipients, which included deficiencies in polyunsaturated fatty acids (PUFA). The goal of this study was to determine the associations between the fatty acid profile and microvascular parameters in KT patients. The fatty acids 22:4n-6 and 20:4n-3 negatively correlated with the wall-to-lumen ratio (WLR), with respective R-values being - 0.39 (p = 0.017) and - 0.405 (p = 0.013), suggesting their potential protective effect on microcirculation, despite their levels being decreased after KT. Additionally, 18:2n-6, a precursor of pro-inflammatory oxylipins, showed a positive correlation with the wall cross-sectional area (WCSA), which may indicate its negative impact on microvascular remodeling. Moreover, 22:5n-6 was associated with greater microcirculatory function reflected by the normoxia oscillatory index (NOI). Associations between microcirculation and branched-chain fatty acids (BCFA) were also observed. Iso C17 and iso C16 correlated positively with lumen diameter with R-values of 0.397 (p = 0.017) and 0.331 (p = 0.049), respectively, suggesting their beneficial effect on microcirculatory structure, while iso C15 was linked to the hyperemic response (HR) index. The study results indicate that certain circulating PUFA and BCFA are significantly associated with microvascular parameters, with most of them in a favorable (vasculoprotective) manner. Since these fatty acids may potentially improve microcirculation and their levels are reduced in KT patients, further studies are needed to explore their potential therapeutic role.