Evaluation of serum fetuin-A relationships with biochemical parameters in patients on hemodialysis

Low serum butyrylcholinesterase is independently related to low fetuin-A in patients on hemodialysis: a cross-sectional study

PURPOSE

Fetuin-A, which plays a protective role against the atherosclerosis and progression of vascular calcification, is decreased in patients on hemodialysis (HD). Fetuin-A and serum butyrylcholinesterase (BChE) levels decrease during malnutrition. We explored whether BChE was independently related to fetuin-A in patients on HD.

METHODS

Laboratory data including BChE and serum fetuin-A were acquired from 230 patients on HD between August 2017 and April 2018. Nutritional status was evaluated using the Geriatric Nutritional Risk Index (GNRI). Abdominal aortic calcification index (ACI) was measured using computed tomography. Patients were stratified into two groups: low fetuin-A (< lowest quartile) and non-low fetuin-A (≥ lowest quartile) groups. Patient background, medication, and laboratory data were compared. The receiver operating characteristic analysis was conducted to determine the optimal cutoff values of BChE and GNRI for lower fetuin-A level. Factors independently related with lower fetuin-A levels were determined using multivariate logistic regression analysis.

RESULTS

The lowest quartile value of fetuin-A and optimal cutoff values of BChE and GNRI were 0.213 g/L, 200 IU/L, and 92.6, respectively. The study included 57 and 173 patients in the low fetuin-A and non-low fetuin-A groups, respectively. Significant between-group differences were observed for age, C-reactive protein (CRP), history of cardiovascular disease, serum albumin, GNRI, and BChE. Multivariate analysis showed that BChE of < 200 IU/L [odds ratio (OR) 3.05], CRP (OR 2.49), and GNRI of < 92.6 (OR 2.34) were independent factors for lower fetuin-A level after adjusting for confounders.

CONCLUSIONS

BChE was a significant independent marker for fetuin-A levels in patients on HD, in addition to GNRI.

The relationship between poor nutritional status and progression of aortic calcification in patients on maintenance hemodialysis

Background

Although aortic calcification has a significant negative impact on prognosis in patients on hemodialysis (HD), risk factors for aortic calcification progression remain unclear. The aim of this study was to investigate the relationship between malnutrition and aortic calcification progression in patients on HD.

Methods

Between April 2015 and October 2016, we treated 232 patients on HD. Of those, we retrospectively evaluated data from 184 patients who had had regular blood tests and computed tomography (CT) scans. The abdominal aortic calcification index (ACI) was quantitatively measured by abdominal CT. Nutritional status was evaluated using the Geriatric Nutritional Risk Index (GNRI). A normalized treatment ratio of functional urea clearance was evaluated by Kt/V. The difference in ACI values between 2015 and 2016 was evaluated as a ΔACI, and patients were stratified into two groups according to ΔACI value: high (≥75th percentile, ΔACI-high group) and low (<75th percentile, ΔACI-low group). Variables such as age, sex, comorbidities, dialysis vintage, serum data, and GNRI were compared between ΔACI-high and ΔACI-low patients. Factors independently associated with a higher ΔACI progression (ΔACI ≥75th percentile) were determined using multivariate logistic analysis.

Results

Median values of ACIs in 2015 and 2016 were 40.8 and 44.6%, respectively. Of 184 patients, 125 (68%) patients experienced ACI progression for 1 year. The median ΔACI and 75th percentile of ΔACI were 2.5% and 5.8%, respectively. The number of patients in the ΔACI-low and ΔACI-high groups were 128 (70%) and 56 (30%), respectively. There were significant differences in sex, presence of diabetic nephropathy, HD vintage, serum albumin, serum phosphate, C-reactive protein, intact parathyroid hormone, Kt/V, and GNRI. Multivariate logistic regression analysis revealed that independent factors associated with a higher ΔACI progression were male sex, serum phosphate levels, HD vintage, and GNRI of < 90.

Conclusions

Our results suggest that poor nutritional status is an independent risk factor for the progression of aortic calcification. Nutrition management may have the potential to improve progression of aortic calcification in patients on HD.

Trial registration

UMIN Clinical Trials Registry UMIN000028050.

Fetuin-A and vascular calcification in Indian end-stage renal disease population

Fetuin-A levels, its correlation with vascular calcification and other biochemical markers of chronic kidney disease-mineral and bone disorder (CKD-MBD) has not been studied in Indian end-stage renal disease population. Forty patients on dialysis for more than 3 months were studied. Biochemical parameters of CKD-MBD, highly sensitive-C reactive protein (hs-CRP), lipid profile and fetuin-A levels were estimated. Multi-slice computed tomography (MSCT) at the level of L1-L4 was done, and calcification score calculated using AJ 130 smart score. Levels of fetuin-A were correlated with calcification score and biochemical markers of CKD-MBD. Mean fetuin-A levels were 0.33 ± 0.098 g/l. Positive correlation of abdominal aortic calcification scores was found with age (P < 0.01) and duration of dialysis (P = 0.018). No correlation was detected between MSCT score, calcium phosphate product, intact parathyroid hormone, vitamin D, triglycerides and fetuin-A, and there was no correlation between fetuin-A levels, age, dialysis duration and calcium phosphate product but a significant correlations with vitamin D3 (P = 0.034), serum albumin (P = 0.002) was detected. Inverse correlation with hs-CRP was obtained. Patients with ischemic heart disease had numerically lower levels of fetuin-A (P = 0.427) and numerically higher MSCT score (P = 0.135). Patients with low hs-CRP (<10) had numerically higher fetuin-A levels (P = 0.090) and significantly low MSCT scores (P = 0.020). Calcium deposition seen on MSCT increases with age and duration of dialysis but is not related to fetuin-A levels. Inconclusive relationship exists with other parameters of CKD-MBD. Large controlled studies are needed to establish the role of fetuin-A in vascular calcification in Indian population.

Fetuin-A and Ghrelin Levels in Children with End Stage Renal Disease and the Effect of a Single Hemodialysis Session on Them

BACKGROUND

Fetuin-A and ghrelin have been implicated in cardiovascular diseases and mortality among end stage renal disease patients. The exact mechanisms have not been fully elucidated. There is robust data supporting an association between ghrelin and various cardiovascular conditions, and some common processes such as inflammation, oxidative stress, and endoplasmic reticulum stress have been implicated.

AIM

This study was conducted to assay serum fetuin-A and ghrelin in chronic renal failure pediatric patients and to study changes in their level that may occur after a single hemodialysis.

MATERIAL AND METHODS

Forty nine pediatric patients suffering from ESRD on maintenance hemodialysis (HD), 20 patients with chronic renal failure (CRF) not on dialysis and 35 healthy subjects as control group were included. The mean age of the study population was 10.58 ± 3.94, 10.62 ± 3.24 and 10.61 ± 3.97 years respectively. Serum fetuin-A and plasma acyl ghrelin levels were measured by using ELISA method.

RESULTS

The present study revealed that predialysis serum fetuin-A level was significantly increased in pediatric HD patients compared with the normal population, while ghrelin levels were significantly reduced. Furthermore, serum levels of fetuin-A decreased significantly after a single HD session.

CONCLUSION

Our study concluded that fetuin-A and acyl ghrelin may play a role in inflammatory process among HD pediatric patients which may account for cardiovascular insults and mortality but their use as biochemical markers among ESRD pediatric patients have limitations due to wide fluctuations.

Vascular calcification: from pathophysiology to biomarkers

The link between vascular calcification (VC) and increased mortality is now well established. Over time, as clinical importance of this phenomenon has begun to be fully considered, scientists have highlighted more and more physiopathological mechanisms and signaling pathways that underlie VC. Several conditions such as diabetes, dyslipidemia and renal diseases are undoubtedly identified as predisposing factors. But even if the process is better understood, many questions still remain unanswered. This review briefly develops the various theories that attempt to explain mineralization genesis. Nonetheless, the main purpose of the article is to provide a profile of the various existing biomarkers of VC. Indeed, in the past years, a lot of inhibitors and promoters, which form a dense and interconnected network, were identified. Given importance to assess and control mineralization process, a focusing on accumulated knowledge of each marker seemed to be necessary. Therefore, we tried to define their respective role in the physiopathology and how they can contribute to calcification risk assessment. Among these, Klotho/fibroblast growth factor-23, fetuin-A, Matrix Gla protein, Bone morphogenetic protein-2, osteoprotegerin, osteopontin, osteonectin, osteocalcin, pyrophosphate and sclerostin are specifically discussed.

Jacalin bound plasma O-glycoproteome and reduced sialylation of alpha 2-HS glycoprotein (A2HSG) in rheumatoid arthritis patients

Glycosylation studies of plasma proteins can reveal information about the onset and progression of diseases, where in the glycan biosynthetic pathways are disturbed as in rheumatoid arthritis (RA). The present study was focused on analysis of O-linked glycoproteins of plasma in RA patients. Two dimensional gel electrophoresis of jacalin bound plasma of RA patients revealed a number of differentially expressed protein spots as compared to healthy controls. Eighteen protein spots were found to have statistically significant (p<0.05) difference in their expression level from four sets of gels and were identified by MALDI-TOF MS. Most of the identified proteins were predicted to be O-glycosylated proteins by Net-O-Gly 3.1 algorithm. Among these the alpha 2HS glycoprotein (A2HSG) was found to be down regulated whereas inter alpha trypsin inhibitor H4 (ITIH4) was up regulated and this was validated by Western blotting. The glycosylation studies showed the reduced N-linked sialylation of A2HSG in RA patients. Altered glycoprotein expression and functional as well as structural studies of glycans might help in the diagnosis of RA and understanding the disease pathogenesis.

Fetuin-A and interleukin-18 levels in ankylosing spondylitis

AIM

Interleukin-18 (IL-18) and fetuin-A have been implicated in atherosclerosis. Preliminary evidence suggests that ankylosing spondylitis (AS) is associated with an increased risk of atherosclerosis. The aim of the present study was to investigate possible abnormalities in IL-18 and fetuin-A levels in AS.

METHODS

Subjects without established cardiovascular (CV) risk factors were studied. Fasting glucose, serum lipids, high sensitive C-reactive protein (hsCRP), erythrocyte sedimentation rate, IL-18 and fetuin-A were assessed. Patients were also evaluated with the Bath Ankylosing Spondylitis Metrology Index, Bath Ankylosing Spondylitis Functional Index, and the Bath Ankylosing Spondylitis Disease Activity Index.

RESULTS

Fourty-five patients with AS (37.4 +/- 9.7 years; 35M/10F) and 29 controls (35.5 +/- 11.1 years; 21M/8F) were studied. Fetuin-A levels were significantly higher in AS patients compared to controls (1023.5 +/- 171.6 vs. 856.9 +/- 207.9 microg/mL, P < 0.001). IL-18 levels were also higher in the AS group but the difference was not significant (184 +/- 186 vs. 140 +/- 115, P = 0.1). Significant but weak correlations were found between fetuin-A, IL-18, hsCRP, low density lipoprotein cholesterol, and triglyceride levels (P < 0.05; r = 0.4, 0.3, 0.2, and 0.3 respectively). Comparison of subjects with respect to the treatment type, disease activity and history of peripheral arthritis yielded no difference regarding fetuin-A and IL-18 between groups.

CONCLUSION

Fetuin-A and IL-18 levels seem to be increased in AS patients regardless of disease activity and treatment type.

Factors associated with aortic stiffness and its change over time in peritoneal dialysis patients

BACKGROUND

An increase in aortic stiffness, as reflected by an increase in pulse wave velocity (PWV), is an important predictor of cardiovascular mortality in dialysis patients. Decreased serum concentration of calcification inhibitor, such as fetuin-A, is inversely related to mortality in haemodialysis patients. Our aim is to investigate the factors associated with aortic stiffness and its change over time in peritoneal dialysis (PD) patients.

METHODS

As a prospective observational study, we analysed 67 PD patients, aged 50 ± 14 years (mean ± SD) and with dialysis duration of 26 (5-58) months (median, interquartile range). At baseline, age, mean arterial pressure (MAP), left ventricular mass (LVM) index, diabetes, serum albumin, calcium (Ca), phosphorus (P) and intact parathyroid hormone (iPTH), uric acid, total bilirubin, high-sensitivity C-reactive protein (hsCRP), fetuin-A, and residual renal function were included in association analysis with aortic stiffness represented by heart-to-femoral PWV (hfPWV). We also evaluated simple vascular calcification score (SVCS) with plain radiograph of the pelvis and both hands. PWV was measured both at baseline and at 1 year. Change of aortic stiffness was determined by △PWV (difference between 1-year PWV and baseline PWV). Time-averaged concentrations were used to evaluate the relation between biologic markers and changes of aortic stiffness.

RESULTS

hfPWV was 1022 ± 276 cm/s at baseline, and hfPWV determined at 1 year was 1069 ± 317 cm/s. Mean serum fetuin-A concentration was 0.34 ± 0.08 g/L. At baseline, aortic PWV positively correlated with age, smoking status, diabetes, MAP, total cholesterol and LDL cholesterol. On the other hand, aortic PWV inversely correlated with fetuin-A, log PTH, haemoglobin and albumin. In a multiple regression model, association of serum fetuin-A (β = -0.329, P = 0.003) with aortic PWV remained significant, along with age (β = 0.512, P < 0.001), MAP (β = 0.215, P = 0.047) and log PTH (β = -0.269, P = 0.025). At follow-up, △MAP (β = 0.500, P < 0.001) and time-averaged TG (aTG) (β = 0.259 P = 0.019) were determinants of △PWV.

CONCLUSIONS

For our PD patients, serum fetuin-A was an independent determinant of aortic stiffness, as well as age, MAP and log PTH. Although 1 year is not sufficient to observe the change of aortic stiffness, some patients exhibited >15% increase of PWV during this period. △MAP and aTG were factors affecting the change of PWV. Follow-up over a longer period is necessary to elucidate factors that determine changes of aortic stiffness over time from PD patients.

Development and validation of an immunoluminometric assay (ILMA) for fetuin-A-glycoprotein

BACKGROUND

To identify dialysis patients with low fetuin-A levels, a sensitive immunoluminometric assay (ILMA) was developed.

METHODS

For the two-site ILMA, one monoclonal antibody was coated to polystyrene beads and one polyclonal antibody was labelled with acridinium ester.

RESULTS

The lower detection threshold was 0.013 g/L, with the normal range 0.20-0.87 g/L (arithmetic mean 0.437 +/- 0.118 g/L). Serum fetuin-A levels in the dialysis patients were significantly lower (arithmetic mean: 0.352 +/- 0.099 g/L, p < 0.0001).

CONCLUSION

This ILMA has been proved to be a reliable method for the determination of serum fetuin-A concentrations in dialysis patients.

Clinical assessment of atherosclerotic parameters and cardiac function in chronic hemodialysis patients

BACKGROUND/AIM

Atherosclerosis is evaluated by carotid mean intima-media thickness (mean IMT), pulse wave velocity (PWV), and the aortic calcification index (ACI). We have attempted to examine if these atherosclerotic parameters are associated with each other and which parameters are closely related to cardiac function in chronic HD patients.

METHODS

The mean IMT, PWV and ACI were examined in 69 maintenance HD patients using carotid ultrasonography, a blood volume plethysmographic apparatus and abdominal CT, respectively. Echocardiographic studies were also performed for measuring left ventricular (LV) geometry. Serum total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, triglyceride, albumin, C-reactive protein (CRP), calcium and phosphate were measured.

RESULTS

The mean IMT correlated positively with ACI (r = 0.461, P < 0.0001) and tended to be correlated with PWV, but did not reach statistical significance. The PWV value correlated positively with ACI (r = 0.494, P <or= 0.0001). The mean IMT correlated positively with the LV mass index (r = 0.273, P = 0.0228), and fractional shortening (FS) correlated negatively with PWV value (r = -0.293, P = 0.0141) and ACI score (r = -0.289, P = 0.0158). Multivariate analyses indicated that the LV mass index was independently associated with mean IMT (P = 0.0231) as well as systolic blood pressure (P < 0.0001), pulse pressure (P < 0.0001) and hemoglobin (P = 0.016), and FS is independently associated with ACI (P = 0.0162) as well as PWV (P = 0.0144) and CRP (P = 0.0375).

CONCLUSION

Atherosclerosis and reduced LV function are associated with increased vascular calcification and arterial stiffness in chronic HD patients.

Meta-analysis and profiling of cardiac expression modules

Heart failure is a complex, complicated disease that is not yet fully understood. We used the Module Map algorithm to uncover groups of genes that have a similar pattern of expression under various conditions of heart stress. These groups of genes are called modules and may serve as computational predictions of biological pathways for the various clinical situations. The Module Map algorithm allows a large-scale analysis of genes expressed. We applied this algorithm to 700 different mouse experiments downloaded from the Gene Expression Omnibus database, which identified 884 modules. The analysis reconstructed partially known principles that play a role in governing the response of heart to stress, thus demonstrating the strength of the method. We have shown a role of genes related to the immune system in conditions of heart remodeling and failure. We have also shown changes in the expression of genes involved with energy metabolism and changes in the expression of contractile proteins of the heart following myocardial infarction. When focusing on another module we noted a new correlation between genes related to osteogenesis and heart failure, including Runx2 and Ahsg, whose role in heart failure was unknown so far. Despite a lack of prior biological knowledge, the Module Map algorithm has reconstructed known pathways, which demonstrates the strength of this new method for analyzing gene profiles related to clinical phenomenon. The method and the analysis presented are a new avenue to uncover the correlation of clinical conditions to the molecular level.