Serum Adipocyte Fatty Acid-Binding Protein Level is Negatively Associated with Vascular Reactivity Index Measured by Digital Thermal Monitoring in Kidney Transplant Patients

Abstract

Adipocyte fatty acid-binding protein (A-FABP) is abundantly found in mature adipocytes and is involved in cardiovascular disease. Our aim is to investigate the association between serum A-FABP levels and endothelial function among kidney transplant (KT) patients. Fasting blood samples were obtained from 80 KT patients. Serum A-FABP levels were measured using a commercially available enzyme immunoassay kit. Endothelial function and vascular reactivity index (VRI) were measured using digital thermal monitoring test. In this study, VRI < 1.0, VRI 1.0–1.9, and VRI ≥ 2.0 were defined as poor, intermediate, and good vascular reactivity, respectively. There were 12 (15.0%), 30 (37.5%), and 38 (47.5%) KT patients categorized as having poor, intermediate, and good vascular reactivity, respectively. Increased serum levels of alkaline phosphatase (p = 0.012), γ-glutamyltranspeptidase (GGT; p = 0.032), and A-FABP (p < 0.001) were associated with decreased vascular reactivity. Multivariable forward stepwise linear regression analysis revealed that age (β = −0.283, adjusted R2 change = 0.072; p = 0.003) and serum log-A-FABP level (β = −0.514, adjusted R2 change = 0.268; p < 0.001) were significantly associated with VRI values in KT patients. We concluded that serum fasting A-FABP level is negatively associated with VRI values and plays a role in endothelial dysfunction of KT patients.

Association between Serum Indoxyl Sulfate Levels and Endothelial Function in Non-Dialysis Chronic Kidney Disease

“…The endothelium is a target of injury even in renal transplantation patients. We recently found that endothelial dysfunction measured by VRI, was correlated with serum adipocyte fatty acid binding protein, which is a potential biomarker of CVD [19]. Here in our research, we similarly assessed endothelial function by using a non-invasive method, the DTM, and found that as the renal function worsened, the values of VRI decreased.…”

Serum Galectin-3 Level Is Positively Associated with Endothelial Dysfunction in Patients with Chronic Kidney Disease Stage 3 to 5

“…The endothelial function of all participants was measured using an FDA-approved device (Endothelix Inc., Houston, TX, USA) with DTM method, with BP cuffs and skin temperature sensors placed on both upper arms and index fingers, respectively [ 32 , 33 ]. In performing the DTM method, we first stably positioned both hands for 3 min, inflated the BP cuff to 50 mmHg greater than the systolic BP, and finally, deflated the BP cuff in 5 min.…”

Serum Osteocalcin Level is Negatively Associated with Vascular Reactivity Index by Digital Thermal Monitoring in Kidney Transplant Recipients

“…VRI has been defined as the maximal temperature difference between the rebound curve and the zero reactivity curves during the period of reactive hyperemia period, calculated by the VENDYS software. VRIs were found to range from 0.0 to 3.5; a VRI of less than 1.0 indicated poor vascular reactivity; a VRI ranging from 1.0 to 1.9, intermediate vascular reactivity; and a VRI of 2.0 or greater, good vascular reactivity [7,11].…”

“…Participants were weighed, wearing lightweight clothing without shoes, to the nearest 0.5 kg, and body height was measured to the nearest 0.5 cm. Body mass index was calculated as the weight in kilograms divided by the height in meters squared [11].…”

“…Fasting blood samples (approximately 5 mL) of all participants were immediately centrifuged at 3000 g for 10 min. An auto-analyzer (Siemens Advia 1800; Siemens Healthcare GmbH, Erlangen, Germany) was used to measure serum levels of blood urea nitrogen (BUN), creatinine, fasting glucose, total cholesterol, triglycerides, calcium, and phosphorus [11]. Commercially available enzyme-linked immunosorbent assays were also used to measure serum total osteocalcin levels (eBioscience, Inc., San Diego, CA, USA) and intact parathyroid hormone (iPTH) levels (Diagnostic Systems Laboratories, Webster, TX, USA) [12].…”