Procoagulant phenotype induced by oxidized high-density lipoprotein associates with acute kidney injury and death

Background: Oxidative stress derived from severe systemic inflammation promotes conversion from high-density lipoprotein HDL to oxidized HDL (oxHDL), which interacts with vascular endothelial cells (ECs). OxHDL acquires procoagulant features playing a role in modulating coagulation, which has been linked with organ failure in ICU patients. However, whether oxHDL elicits a ECs-mediated procoagulant phenotype generating organ failure and death, and the underlying molecular mechanism is not known. Therefore, we studied whether oxHDL-treated rats and high-oxHDL ICU patients exhibit a procoagulant phenotype and its association with kidney injury and mortality and the endothelial underlying molecular mechanism. Methods: Human ECs, oxHDL-treated rats and ICU patients were subjected to several cellular and molecular studies, coagulation analyses, kidney injury assessment and mortality determination. Results: OxHDL-treated ECs showed a procoagulant protein expression reprograming characterized by increased E-/P-selectin and vWF mRNA expression through specific signaling pathways. OxHDL-treated rats exhibited a procoagulant phenotype and modified E-/P-selectin, vWF, TF and t-PA mRNA expression correlating with plasma TF, t-PA and D-dimer. Also, showed increased death events and the relative risk of death, and increased creat-inine, urea, BUN/creatinine ratio, KIM-1, NGAL, beta 2M, and decreased eGFR, all concordant with kidney injury, correlated with plasma TF, t-PA and D-dimer. ICU patients showed correlation between plasma oxHDL and increased creatinine, cystatin, BUN, BUN/creatinine ratio, KIM-1, NGAL, beta 2M, and decreased GFR. Notably, ICU high-oxHDL patients showed decreased survival. Interestingly, altered coagulation factors TF, t-PA and D-dimer correlated with both increased oxHDL levels and kidney injury markers, indicating a connection between these factors. Conclusion: Increased circulating oxHDL generates an endothelial-dependent procoagulant phenotype that as-sociates with acute kidney injury and increased risk of death.

Automated summary

Severe systemic inflammation can lead to oxidative stress, promoting the conversion of high-density lipoprotein (HDL) to oxidized HDL (oxHDL), which interacts with vascular endothelial cells (ECs). OxHDL can acquire procoagulant features and modulate coagulation, which has been linked with organ failure in ICU patients. However, the exact role and underlying molecular mechanism of oxHDL in generating a procoagulant phenotype and causing organ failure and death are still unknown.