Indoxyl Sulfate Promotes Arterial Thrombosis in Rat Model via Increased Levels of Complex TF/VII, PAI-1, Platelet Activation as Well as Decreased Contents of SIRT1 and SIRT3

Abstract

Patients suffering from chronic kidney disease (CKD) are at a 20-fold higher risk of dying due to cardiovascular diseases (CVDs), primarily thrombosis following vascular injury. CKD is connected with retention of uremic toxins, especially indoxyl sulfate (IS), which are currently considered as a non-classical CKD-specific risk factor for CVDs. The present study aimed to examine the effect of chronic exposure to IS on the hemostatic system and arterial thrombosis in a model without greater interferences from the uremic milieu consisting of additional uremic toxins. Forty-eight male Wistar Crl:WI (cmdb) rats were divided into three groups: one control group and two experimental groups, which were exposed to 100 or 200 mg/kg of b.w./day of IS in drinking water for a period of 28 days. The control group received water without IS. At the end of the experiment, the induction of arterial thrombosis was performed. We investigated the impact of IS on thrombosis incidence, kinetics and strength of clot formation, platelet activity, aortic contents of sirtuin (SIRT) 1 and sirtuin 3 (SIRT3), hemostatic system, cardiorespiratory parameters, biochemistry of plasma and urine as well as histology of the thrombus, kidney, and liver. Obtained data revealed that chronic exposure to IS promotes arterial thrombosis via increased levels of complex tissue factor/factor VII, plasminogen activator inhibitor-1 (PAI-1), platelet activation, as well as decreased aortic levels of SIRT1 and SIRT3. Therefore, we hypothesize that IS enhances primary hemostasis leading to augmented formation of platelet plug with increased amounts of fibrin and affects secondary hemostasis through the influence on plasma coagulation and fibrinolysis factors, which results in the increased kinetics and strength of clot formation. The findings described may contribute to a better understanding of the mechanisms leading to increased thrombotic events in patients with CKD with elevated levels of IS.

Indoxyl Sulfate, a Uremic Endotheliotoxin

“…With the highest dosage, IS decreased the clotting time, increased the total area of the thrombus and the maximum firmness of the clot compared to control. Similar evidence of thrombus formation was reported after chronic oral exposure to IS in rat model [62] and in the mice models with higher IS doses (more than 30 mg/kg) [63]. Recently, in a model of cancer-associated thrombosis, increased levels of IS were observed and associated with more extensive thrombosis [64] extending the endotheliotoxic role of IS beyond uremia.…”

“…Karbowska et al described that IS exposure induces thrombosis in two non-CKD animal models: by direct electric stimulation of carotid artery in the rat model after chronic oral exposure to IS [62] or after one injection of IS [63] and by laser-induced endothelial injury [62] in the mouse model after one injection of IS. In the rat model, they described a higher incidence of thrombosis and a heavier thrombus after one injection of IS [63].…”

“…IS Implication in NO Production and Impaired Neovascularization IS known to induce endothelial toxicity in vitro. An increase in endothelial microparticles [62], a decrease in NO bioavailability and an increase in reactive oxygen species (ROS) production [40,[73][74][75][76] were reported when endothelial cell are exposed to IS. NO is a key mediator of endothelial cell function and angiogenesis.…”

The impact of antihypertensive pharmacotherapy on interplay between protein-bound uremic toxin (indoxyl sulfate) and markers of inflammation in patients with chronic kidney disease

“…It is proved that complexity in antihypertensive treatment in CKD patients allows for satisfactory BP control and elimination of the effect of accumulated uremic toxins on modifying bloodstream flow properties. Equally, strong evidence in the literature could be found in a case of associations between IS levels and values of eGFR (negative correlation) as well as creatinine concentration (positive correlation) in CKD [9]. Our study is bringing the same results, regardless of the examined CKD subgroup.…”

Molecular and Cellular Mechanisms that Induce Arterial Calcification by Indoxyl Sulfate and P-Cresyl Sulfate

“…IS has been associated with the regulating mammalian methyltransferase Set7/9, an epigenetic inducer of inflammatory genes, in VSMCs [44]. Moreover, data from an experimental rat study showed that IS exposure induces arterial thrombosis via decreased aortic levels of sirtuin 1, a class III histone deacetylase involved in oxidative stress [45]. We conducted a curated chemical and genomic/proteomic perturbagen matching analysis to predict upstream regulators that could be responsible for the observed changes in the arterial proteins linked to inflammation and coagulation signaling pathways.…”