Hepatocyte growth factor predicts survival and relates to inflammation and intima media thickness in end-stage renal disease

Serum Hepatocyte Growth Factor Concentration Correlates with Albuminuria in Individuals with Optimal Blood Pressure and Untreated Arterial Hypertension

Background/Objectives: Hepatocyte growth factor (HGF) is a protective factor against acute renal injury and chronic renal fibrosis. A positive correlation between HGF and blood pressure (BP) has been established. This study aimed to determine the association between serum HGF concentration and albuminuria in subjects with optimal blood pressure (OBP) and untreated arterial hypertension (UAH), as well as its association with BP levels, serum glucose levels, and inflammatory markers. Methods: Data from 563 subjects were analyzed. Albuminuria was normalized to urine creatinine and expressed as the albumin/creatinine ratio (ACR). HGF, serum glucose, C-reactive protein, and blood leucocyte counts were measured. BP was measured and subjects were divided into optimal blood pressure (BP < 120/80 mmHg, N = 295) and untreated arterial hypertension (BP > 140/90 mmHg, N = 268) groups. Results: The subjects with UAH were significantly older and had higher values of body mass index, waist circumference, serum total and LDL cholesterol levels, triglyceride levels, fasting glucose levels, and ACR (all p < 0.001). A significant positive correlation was found between serum HGF concentration and ACR in both groups. There was no difference or correlation between HGF and BP or inflammatory markers in either group. The multivariate regression analysis identified serum HGF concentration as a strong predictor of ACR increase (Beta = 0.376, p < 0.001). Conclusion: This study found that serum HGF concentration is associated with albuminuria not only in individuals with untreated arterial hypertension, but also in those with optimal blood pressure. The results suggest that serum HGF is an independent predictor of ACR increase in both groups.

Circulating growth factors and cardiac remodeling in the community: The Framingham Heart Study

BACKGROUND AND AIMS

Cardiac and vascular growth factors (GF) may influence myocardial remodeling through cardiac growth and angiogenic effects. We hypothesized that concentrations of circulating GF are associated with cardiac remodeling traits.

METHODS

We related blood concentrations of vascular endothelial GF (VEGF), VEGFR-1 (sFlt1), angiopoietin 2 (Ang-2), soluble angiopoietin type-2 receptor (sTie2), hepatocyte GF (HGF), insulin-like GF (IGF)-1, IGF binding protein (IGFBP)-3, and growth differentiation factor-15 (GDF-15) to echocardiographic traits in 3151 Framingham Study participants (mean age 40 years, 55% women). We evaluated the following measures: left ventricular (LV) mass index (LVMi), LV ejection fraction (LVEF), global longitudinal strain (GLS), mitral E/e', and aortic root diameter (AoR). All biomarker values were sex-standardized.

RESULTS

In multivariable-adjusted analyses, higher GDF-15 concentrations were associated with higher log-LVMi (β = 0.009 per SD, P = 0.01). Similarly, sTie2 concentrations were positively associated with log-E/e' (β = 0.011 per SD, P = 0.04). IGF-1 and Ang-2 concentrations were positively and negatively associated with GLS, respectively (βIGF-1 = 0.16 per SD and βAng-2 = -0.15 per SD, both P < 0.05), whereas higher sFlt1 and Ang-2 levels were associated with smaller log-AoR (βsFlt1 = -0.004 per SD and β Ang-2 = -0.005 per SD, respectively; P < 0.05).

CONCLUSION

In our large community-based sample, we observed patterns of associations between several circulating vascular GF and cardiac remodeling indices that are consistent with the known biological effects of these pro- and anti-angiogenic factors on the myocardium and conduit arteries. Additional studies are warranted to replicate our findings and assess their prognostic significance.

Elevated Circulating Osteoprotegerin Levels in the Plasma of Hemodialyzed Patients With Severe Artery Calcification

We studied the correlations between circulating osteoprotegerin (OPG) level and radial artery calcification (RAC) assessed histologically and carotid artery intima-media thickness (CCA-IMT). Moreover, we studied the relationship between OPG levels and all-cause and cardiovascular (CV) mortality during a 5-year observation period. The study comprised 59 CKD patients (36 hemodialyzed (HD), 23 predialysis). The biochemical parameters included: creatinine, calcium, phosphate, intact parathormone, C-reactive protein, interleukin-6, tumor necrosis factor receptor II (TNFRII), transforming growth factor-β, hepatocyte growth factor, fibroblast growth factor 23, osteonectin (ON), osteopontin, osteoprotegerin, and osteocalcin. CCA-IMT and the presence of atherosclerotic plaques was assessed by ultrasound. Fragments of radial artery obtained during creation of HD access were prepared for microscopy and stained for calcifications with alizarin red. RAC was detected in 34 patients (58%). In multiple regression adjusted for dialysis status, TNFRII, ON and Framingham risk score (FRS) were identified as the independent predictors of OPG. Serum OPG above the median value of 7.55 pmol/L significantly predicted the presence of RAC in simple logistic regression (OR 5.33; 95%CI 1.39-20.4; P = 0.012) and in multiple logistic regression adjusted for FRS, dialysis status and CCA-IMT values (OR 6.56; 95%CI 1.06-40.6; P = 0.036). OPG levels above the median were associated with higher CCA-IMT values (1.02 ± 0.10 vs. 0.86 ± 0.13; P < 0.001) and predicted the presence of atherosclerotic plaques in carotid artery (OR 14.4; 95%CI 2.84-72.9; P < 0.001), independently of FRS, dialysis status and RAC. In this study, elevated serum OPG levels correlated with higher CCA-IMT, the presence of atherosclerotic plaques and the severity of the RAC independently of each other. During follow-up, 25 patients (42%) died, including 21 due to CV causes. In multiple Cox regression, OPG above the median predicted overall survival independently of dialysis status, Framingham risk score, CCA-IMT above the median value, and the presence of atherosclerotic plaques in CCA, but not independently of RAC. We postulate that circulating OPG may play a dual role as a marker for both medial arterial calcification and atherosclerosis, hence it seems to be a valuable tool for assessing CV risk in patients with CKD. OPG might be an early indicator of all-cause mortality in CKD patients with advanced medial arterial calcification.

Evaluation of endothelial dysfunction in patients with familial Mediterranean fever: the relationship between the levels of asymmetric dimethylarginine and endocan with carotid intima-media thickness and endothelium-dependent vasodilation

It has been suggested that there is an ongoing subclinical inflammation in familial Mediterranean fever (FMF) patients also in attack-free periods as well. Due to this ongoing inflammation, endothelial dysfunction (ED) may develop. Previously, ED has been suggested to increase the risk of the atherosclerosis and cardiovascular disease (CVD). Endocan is recognized as a specific molecule of the endothelium and has been shown to increase in some cases associated with inflammation. However, there is not sufficient data whether those with FMF could develop ED in the early period of life. In this study, we aimed to investigate ED and its relation with endocan in young FMF patients. A total of 57 male patients diagnosed with FMF according to the Tel Hashomer criteria and a total of 33 healthy males with similar characteristics to the patient group were included in this research. Complete blood count, erythrocyte sedimentation rate (ESR), fibrinogen, serum glucose, serum LDL cholesterol (LDL-C) and triglyceride (TG), asymmetric dimethylarginine (ADMA), and endocan levels were tested from fasting blood samples. Moreover, carotid intima-media thickness (CIMT) and flow-mediated dilatation (FMD) were measured. The endocan levels of the FMF patients during an attack-free period were significantly higher than those of the control group (p < 0.001). On the other hand, FMD measurements were significantly lower among FMF patients (p < 0.001). ADMA levels were higher in the patient group; however, this difference was similar (p > 0.05). CIMT values were similar among FMF patients and healthy controls (p > 0.05). These results have suggested that ED may develop in the patients with FMF who have no additional CVD risk, even during young adulthood, and endocan may be a favorable biomarker at demonstration of ED than ADMA among FMF patients.

Hepatocyte growth factor (HGF) and hemodialysis: physiopathology and clinical implications

Hepatocyte growth factor (HGF) is a pleiotropic cytokine which exerts a variety of effects on several cells, being involved in the regulation of many biological processes, such as inflammation, tissue repair, morphogenesis, angiogenesis, tumour propagation, immunomodulation of viral infections and cardio-metabolic activities. Patients undergoing regular hemodialysis (HD) present elevated levels of HGF, mainly due to the leukocyte activation associated with HD treatment. High HGF levels might account for specific clinical features of HD patients, i.e. mild liver damage in course of HCV-infection and high cardiovascular risk profile. Moreover, in patients with acute kidney injury, the induction of HGF may represent a crucial step to promote renal recovery, which can have important prognostic consequences in the short and long-term. In this review we discuss the mechanisms underlying HGF production in HD patients, the role of HGF in this particular patient population and the potential clinical implications derived from the study of HGF in HD patients.

Proinflammatory Cytokines (IL-1α, IL-6) and Hepatocyte Growth Factor in Patients with Alcoholic Liver Cirrhosis

Background. The aim of the study was to assess the activity of interleukin-1α, interleukin-6, and hepatocyte growth factor protein (HGF) in serum of patients with alcoholic liver cirrhosis. Materials and Methods. Sixty patients with alcoholic liver cirrhosis treated in various hospitals were randomly enrolled. The stage of cirrhosis was assessed according to the Child-Turcotte-Pugh scoring system. The control group consisted of ten healthy persons without liver disease, who did not drink alcohol. Additionally, the group of alcoholics without liver cirrhosis was included in the study. The activity of interleukin-1α, interleukin-6, and HGF in blood plasma of patients and controls was measured using the sandwich enzyme immunoassay technique with commercially available quantitative ELISA test kits. Results. Higher concentrations of HGF protein were demonstrated in patients with Child class B and Child class C liver cirrhosis, compared to controls and alcoholics without liver cirrhosis. Moreover, significantly higher concentrations of HGF protein were found in patients with Child class C liver cirrhosis compared to patients with Child class A liver cirrhosis (p < 0.05). The concentrations of interleukin-1α in patients with Child class B and Child class C liver cirrhosis were significantly higher in comparison with controls. Significantly higher concentrations of interleukin-6 were demonstrated in Child class C, compared to Child class A.

Serum hepatocyte growth factor is associated with truncal fat mass and increased mortality in chronic kidney disease stage 5 patients with protein-energy wasting

BACKGROUND

Obese sarcopenia characterized by increased fat mass and protein-energy wasting (PEW) is not uncommon in chronic kidney disease (CKD) stage 5 patients in whom it is associated with worse outcomes. Serum hepatocyte growth factor (HGF) is associated with obesity in the general population and is increased in CKD patients in whom its association with body composition is not known. We studied the associations between HGF, PEW and body composition, and between HGF and mortality, in CKD stage 5 patients starting dialysis.

METHODS

In 224 CKD stage 5 patients (139 males, mean age 52 years, mean glomerular filtration rate (GFR) 6.6 mL/min), blood samples were obtained for analyses of HGF, high-sensitivity C-reactive protein (hsCRP), glucose, insulin and lipids. Total fat mass index (FMI), truncal fat mass index (TFMI) and lean body mass index (LBMI) assessed by dual-energy X-ray absorptiometry and PEW assessed by subjective global assessment (SGA) were recorded at baseline. Patients were followed up for 5 years.

RESULTS

Serum HGF levels were higher in patients with high TFMI versus low TFMI [3.1 (IQR: 2.4-4.5) versus 2.7 (IQR: 1.9-3.8) ng/mL; P = 0.01] and in those with PEW versus non-PEW [3.4 (IQR: 2.4-3.6) versus 2.8 (IQR: 2.1-3.8) ng/mL; P = 0.03]. Patients with both high TFMI and presence of PEW had significantly (P < 0.001) higher HGF concentration [4.4 (IQR: 3.3-6.6) ng/mL] than other patient groups (high TFMI and non-PEW, low TFMI and PEW or low TFMI and non-PEW). Multivariate linear regression showed that TFMI was an independent predictor of HGF (R(2) = 0.21, P = 0.048). In Cox analysis, patients with high HGF and presence of PEW had worse all-cause mortality after adjusting for age, gender and hsCRP (HR: 3.59, 95% CI: 1.19-5.35).

CONCLUSIONS

Increased TFMI was an independent predictor of HGF in CKD stage 5 patients. Moreover, an elevated HGF level increased the mortality risk in the presence of PEW. These results suggest a central role of HGF in the metabolic and nutritional alterations in CKD stage 5 patients.

Relationship of increased circulating adrenomedullin with cardiac dysfunction, inflammation, oxidative stress and volume overload in hemodialysis patients

Adrenomedullin (AM) is a peptide involved in cardiovascular homeostasis. The aim of our study was to investigate whether circulating AM might be related to cardiac function, volume overload, oxidative stress and inflammation in hemodialysis patients. Plasma adrenomedullin, C-reactive protein (CRP), oxidized LDL (ox-LDL), lipoprotein (a), systolic and diastolic cardiac functions were assessed before hemodialysis in 80 patients as well as in 40 healthy control subjects. Plasma adrenomedullin levels were significantly higher in the hemodialysis group compared to the control group. Plasma adrenomedullin levels were negatively correlated with systolic and diastolic blood pressure, S/D ratio, deceleration time, left ventricular ejection fraction, ox-LDL and lipoprotein (a). However, it was positively correlated with CRP, delta body weight, mitral E/A wave, and inferior vena cava diameter. Higher plasma adrenomedullin levels may provide a possible index of cardiac dysfunction, systemic inflammation, and volume overload conditions in haemodialysis patients with concomitant cardiovascular disease. In addition, the negative correlation between ox-LDL, lipoprotein (a) and adrenomedullin may suggest that endogenous AM is an important protective factor in anti-atherosclerosis and might be useful as a new target for prevention and therapy for the disease.

Proinflammatory cytokines, hepatocyte growth factor and adipokines in peritoneal dialysis patients

Chronic inflammation is a well-recognized complication in dialysis patients and a potential role of the adipose tissue as an important tissue of origin contributing to inflammation has been proposed. Stable peritoneal dialysis (PD) patients were enrolled to investigate the relationship between serum levels of proinflammatory cytokines and adipokines. Our results revealed that there was a strong association between high sensitivity C-reactive protein and interleukin (IL)-6 and tumor necrosis factor-alpha (TNF-alpha) but not with IL-10 and IL-18. IL-6 correlated with TNF-alpha, IL-10, and IL-18. No association was found between IL-10 and IL-18. Adiponectin was positively correlated with all proinflammatory cytokines, except IL-10. No significant association was found between resistin and proinflammatory cytokines. Hepatocyte growth factor (HGF) was directly related to proinflammatory cytokines but not with adipokines. The presence of residual kidney function (RKF) affected IL-6, TNF-alpha, and HGF levels. The peritoneal transport property did not influence inflammatory cytokine and adipokine levels. In conclusion, there was a close relationship between proinflammatory cytokines and adipokines. HGF correlated with proinflammatory cytokines but not with adipokines. The PD-related factors such as RKF, peritoneal property and dialysis glucose load affected levels of proinflammatory cytokines. Body mass index was an important determinant of leptin and adiponectin in PD patients.

Inflammation as a cause of malnutrition, atherosclerotic cardiovascular disease, and poor outcome in hemodialysis patients

Cardiovascular disease (CVD) remains the major cause of morbidity and mortality in end-stage renal disease (ESRD) patients treated by hemodialysis (HD). Although traditional risk factors are common in dialysis patients, they may not alone be sufficient to account for the unacceptable high prevalence of CVD in this patient group. Recent evidence demonstrates that chronic inflammation, a nontraditional risk factor that is commonly observed in HD patients, may cause malnutrition and progressive atherosclerotic CVD by several pathogenetic mechanisms. The cause(s) of inflammation in HD patients is multifactorial and includes both dialysis-related (such as graft and fistula infections, bioincompatibility, impure dialysate, and back-filtration) and dialysis-unrelated factors. Although inflammation may reflect underlying CVD, an acute-phase reaction may also be a direct cause of vascular injury. Available data suggest that proinflammatory cytokines play a central role in the genesis of both malnutrition and CVD in ESRD. Thus, it could be speculated that suppression of the vicious cycle of malnutrition, inflammation, and atherosclerosis (MIA syndrome) would improve survival in dialysis patients. As there is not yet any recognized, or even proposed, targeted treatment for ESRD patients with chronic inflammation; it would be of considerable interest to study the long-term effect of various anti-inflammatory treatment strategies on nutritional and cardiovascular status as well as outcome in these patients.

Scatter Factors in renal disease: Dr. Jeckyll and Mr. Hyde?

The Scatter Factors are two homologous proteins, named Scatter Factor/Hepatocyte Growth Factor and Macrophage Stimulating Protein. Their receptors are the products of two oncogenes, Met and Ron, respectively. The Scatter Factors induce movement, stimulate proliferation, regulate apoptosis and are morphogenic, i.e. operate an integrated program that seems tailored to drive organ development and to regenerate injured tissues. On the other hand, Scatter Factors may be responsible for pathologic tissue remodeling, infiltration of inflammatory cells, and tumor growth and diffusion. The review describes the involvement of Scatter Factors in renal disease, including acute renal failure, glomerulonephritis, chronic fibrosing nephropathies, dialysis, renal transplantation and renal tumors, and discusses the double-faced role of Scatter Factors, that play either a protective or a pathogenic role.

Consequences of low plasma histidine in chronic kidney disease patients: associations with inflammation, oxidative stress, and mortality

BACKGROUND

Histidine is considered as an antiinflammatory and antioxidant factor. Histidine deficiency may contribute to an impaired nutritional state in patients with chronic kidney disease (CKD).

OBJECTIVE

We aimed to investigate the consequences of plasma histidine deficiency in CKD patients.

DESIGN

CKD patients (n = 325; 203 M) with a median age of 54 y (range: 19-70 y) were evaluated shortly before the beginning of renal replacement therapy. The median glomerular filtration rate was 6.4 mL/min (range: 0.8-14.5 mL/min). Nutritional status was assessed by subjective global assessment. Survival was followed for up to 60 mo; 101 patients died.

RESULTS

Plasma histidine concentrations were significantly lower in CKD patients with history of cardiovascular disease, presence of plaques, protein-energy wasting, and inflammation. Plasma histidine was negatively associated with age, C-reactive protein, interleukin-6, leukocytes, thrombocytes, fibrinogen, hepatocyte growth factor, adhesion molecules, insulin-like growth factor-1, and 8-hydroxy-2'-deoxyguanosine and was positively associated with handgrip strength, hemoglobin, S-albumin and fetuin-A. A multivariate regression analysis showed that histidine concentrations were independently associated with hepatocyte growth factor, hemoglobin, and fetuin-A. In unadjusted analysis, a low histidine concentration was associated with all-cause mortality (log rank chi-square test = 8.9; P = 0.002). After adjustment for age, sex, cardiovascular disease, inflammation, diabetes mellitus, serum S-albumin, and amino acid supplementation, the association between low histidine and mortality remained significant (hazard ratio: 1.55; 95% CI: 1.02, 2.40; P < 0.05).

CONCLUSION

Low plasma concentrations of histidine are associated with protein-energy wasting, inflammation, oxidative stress, and greater mortality in CKD patients.

Differential associations of traditional and non-traditional risk factors with carotid intima-media thickening and plaque in peritoneal dialysis patients

BACKGROUND

This study sought to examine the associations of traditional and non-traditional cardiovascular risk factors with carotid intima-media thickening and plaque in peritoneal dialysis (PD) patients.

METHODS

A cross-sectional study was performed in 147 PD patients with carotid intima-media thickness (IMT) and plaque assessed by B-mode ultrasonography and fasting blood collected for biochemical measurements.

RESULTS

On univariate analysis, age, smoking history, fibrinogen, C-reactive protein (CRP), adiponectin, fetuin-A, lipoprotein(a) and diastolic blood pressure were associated with carotid IMT while age, smoking history, diabetes, CRP and diastolic blood pressure were associated with carotid plaque. Using multivariate analysis, elevated CRP (p = 0.015) and serum calcium (p = 0.022) were associated with carotid plaque but not with IMT. CRP and serum calcium were synergistically associated with carotid plaque in that those with CRP > median and serum calcium > median showed the highest prevalence of carotid plaque than either factor alone (p = 0.003).

CONCLUSIONS

An elevated CRP appeared to be a better biomarker of presence of carotid plaque than intima-media thickening. Furthermore, CRP and serum calcium showed synergistic association with presence of carotid plaque. However, our study was limited by the cross-sectional design and baseline laboratory abnormalities were inevitably confounded by the treatment already given, resulting in difficulty to distinguish cause and effect relationship. Nevertheless, these observations warrant further investigation as it may potentially have important implications on differentiating therapeutic strategies for reducing carotid IMT and plaque progression in PD patients.

Pulse Pressure Is an Independent Predictor of Aortic Stiffness in Patients with Mild to Moderate Chronic Kidney Disease

BACKGROUND

In patients with end-stage renal disease pulse wave velocity (PWV) has been widely assessed, but its behavior in mild to moderate chronic kidney disease (CKD) has been less investigated. We evaluated PWV in mild to moderate CKD.

METHODS

We studied 31 patients with grade II-IV CKD. Aortic PWV (aPWV), aortic and upper limb augmentation index, creatinine clearance, C-reactive protein, serum fibrinogen, interleukin-1, interleukin-6, tumor necrosis factor, albumin, total and high-density lipoprotein cholesterol and blood pressure were evaluated.

RESULTS

aPWV (7.95 +/- 0.64 m/s), but not augmentation index was significantly higher (p = 0.03) in CKD patients than age-matched healthy subjects (aPWV: 6.24 +/- 0.43 m/s; upper limb: 32.8 +/- 1.9; aortic: 27.7 +/- 1.9). At univariate regression analysis, aPWV was significantly correlated with age (r = 0.44; p = 0.013), interleukin-6 (r = 0.43; p = 0.027), pulse (r = 0.39; p = 0.029), systolic blood pressure (r = 0.37; p = 0.038) and tumor necrosis factor (r = 0.39; p = 0.029). At multivariate analysis, pulse pressure was the only significant independent determinant (beta = 0.37; p = 0.05) of aPWV.

CONCLUSION

The results of this study confirm an aPWV increase in mild to moderate CKD and emphasize association between pulse pressure and PWV, independently of renal failure.

Association Between Carotid Artery Intima-Media Thickness and Early-Stage CKD in a Chinese Population

BACKGROUND

Increased carotid artery intima-media thickness (IMT) predicts future vascular events in the general population. However, the relationship between IMT and chronic kidney disease (CKD) seldom was tested in subjects with early-stage CKD.

STUDY DESIGN

Cross-sectional study.

SETTING & PARTICIPANTS

1,046 residents in 1 district of Beijing participated in the study.

OUTCOMES & MEASUREMENTS

Carotid artery IMT was measured by means of high-resolution B-mode ultrasonography. Estimated glomerular filtration rate (eGFR) was calculated using the modified Modification of Diet in Renal Disease Study equation based on data for Chinese patients with CKD. Albuminuria was evaluated by means of urinary albumin-creatinine ratio on a morning spot urine sample.

RESULTS

Compared with subjects with eGFR greater than 90 mL/min/1.73 m(2) (>1.50 mL/s/1.73 m(2)), subjects with eGFR of 60 to 89 mL/min/1.73 m(2) (1.00 to 1.49 mL/s/1.73 m(2)) and 30 to 59 mL/min/1.73 m(2) (0.50 to 0.99 mL/s/1.73 m(2)) had higher mean IMT (0.74 +/- 0.27 versus 0.82 +/- 0.30 versus 0.94 +/- 0.38 mm; P < 0.001). IMTs of subjects with albuminuria tended to be higher than the mean value (0.79 +/- 0.29 versus 0.93 +/- 0.38 mm; P < 0.001). eGFR and urinary albumin-creatinine ratio significantly correlated with IMT in univariable analysis, but not after adjusting for traditional cardiovascular disease risk factors.

LIMITATIONS

Selection bias and low prevalence of CKD might affect the strength of the study.

CONCLUSIONS

In this Chinese population older than 40 years, carotid artery IMT was significantly higher in subjects with early-stage CKD. The greater prevalence of cardiovascular disease risk factors in patients with CKD appeared to account for the higher carotid artery IMT.

Adipose tissue production of hepatocyte growth factor contributes to elevated serum HGF in obesity

Serum HGF is elevated in obese individuals. This study examined the contribution of excess adipose tissue to increased circulating HGF levels in obesity. Serum HGF was measured by ELISA before and after weight loss due to bariatric surgery or a 24-h fast. At 6.1 +/- 0.1 mo following surgery, BMI (50.6 +/- 1.6 vs. 35.1 +/- 1.3 kg/m(2); P < 0.0001) and serum HGF were significantly decreased (1,164 +/- 116 vs. 529 +/- 39 pg/ml, P < 0.001). A 24-h fast did not change serum HGF, but serum leptin was significantly reduced (67.7 +/- 7.1 vs. 50.3 +/- 8.3 ng/ml, P = 0.02). HGF secretion in vitro from adipocytes of obese (BMI 40.3 +/- 2.8 kg/m(2)) subjects was significantly greater (80.9 +/- 10.4 vs. 21.5 +/- 4.0 pg/10(5) cells, P = 0.008) than release from adipocytes of lean (BMI 23.3 +/- 1.4 kg/m(2)) subjects. HGF mRNA levels determined by real-time RT-PCR were not different in adipocytes from lean (BMI 24.0 +/- 0.8 kg/m(2)) and obese (45.7 +/- 3.0 kg/m(2)) subjects, but serum HGF was significantly elevated in the obese individuals studied (787 +/- 61 vs. 489 +/- 49 pg/ml, P = 0.001). TNF-alpha (24 h treatment) significantly increased HGF release from subcutaneous adipocytes 23.6 +/- 8.3% over control (P = 0.02). These data suggest that elevated serum HGF in obesity is in part attributable to excess adipose tissue and that this effect can be reversed by reducing adipose tissue mass through weight loss. Increased HGF secretion from adipocytes of obese subjects may be due to posttranscriptional events possibly related to adipocyte size and stimulation by elevated TNF-alpha in the adipose tissue of obese individuals.

Risk factors for de novo acute cardiac events in patients initiating hemodialysis with no previous cardiac symptom

An initial major adverse cardiac event (MACE) is an important predictor of future cardiovascular events in patients with chronic kidney disease (CKD). We sought to identify factors influencing occurrence of initial MACE in new maintenance hemodialysis patients without previous cardiac symptoms during the predialysis phase of CKD. Among 112 participating patients with no predialysis cardiac history, 57 underwent coronary angiography, whereas the other 55 underwent stress thallium-201 single-photon emission computed tomography within 1 month of beginning hemodialysis to detect asymptomatic coronary artery disease (CAD). In subsequent follow-up for a median of 24 months, subjects experiencing an initial MACE were compared with those who did not have such an event based on several clinical parameters at the end of predialysis phase. Asymptomatic CAD was present in 47 patients (42%), who had a higher cumulative MACE rate, than subjects without CAD (49 vs 3%, P<0.001). Multivariate Cox's regression analysis showed that three variables independently predicted initial MACE: asymptomatic CAD (hazard ratio or HR, 611.31; 95% confidence interval or CI, 14.07-26549.23; P<0.001), diabetes (HR, 20.41; 95% CI, 2.07-200.00; P=0.010), and each 1 mg/l increment in C-reactive protein (CRP) (HR, 1.94; 95% CI, 1.27-2.94; P=0.002). In conclusion, detection of asymptomatic CAD, presence of diabetes, or elevated CRP at the end of the predialysis phase were significantly associated with occurrence of an initial MACE in CKD patients starting hemodialysis who had no CAD symptoms.

Inflammatory markers and hepatocyte growth factor in sustained hemodialysis hypotension

Hypotension is an important complication of hemodialysis. The pathogenesis of this complication remains unclear. The role of chronic inflammation in chronic dialysis-associated hypotension has not been investigated. A total of 38 dialysis patients with chronic hypotension were identified. Their demographic and biochemical data, inflammatory markers (high sensitivity C-reactive protein [hs-CRP] and interleukin-6 [IL-6]), hepatocyte growth factor (HGF), leptin, and adiponectin levels were measured and compared with those of another 87 nonhypotensive dialysis patients. No between-group differences in their clinical features, underlying renal disease were found. Levels of serum albumin, leptin, adiponectin, and HGF were similar between the two groups. The serum albumin levels were inversely correlated with hs-CRP and IL-6. Adiponectin was negatively correlated with hs-CRP and leptin. HGF showed a positive relation with hs-CRP. No association was found between adiponectin and HGF. Therefore, chronic inflammation is prevalent in the dialysis population, and serum HGF level is associated with inflammation but not with chronic dialysis hypotension.

Serum hepatocyte growth factor levels predict long-term clinical outcome after percutaneous coronary revascularization

AIMS

To evaluate, in patients referred for elective percutaneous coronary revascularization (PCR) without heparin pre-treatment, the relationship between baseline serum levels of the angiogenic growth factors, vascular endothelial growth factor (VEGF) and hepatocyte growth factor (HGF), and clinical outcome.

METHODS AND RESULTS

In 488 consecutive patients undergoing elective coronary angioplasty, hsC-reactive protein, HGF, and VEGF levels were measured before heparin administration. The primary endpoint, a composite of death and myocardial infarction, occurred in 44 patients at a median follow-up of 14.9 months. At baseline, VEGF levels were related to C-reactive protein levels and inversely related to age; HGF levels were related to C-reactive protein levels, diabetes, and recent clinical instability. In the univariate analysis, HGF had a significant positive relationship (P=0.003) with the primary endpoint. A similar trend was observed for VEGF (P=0.11). The only three variables significantly associated with the primary endpoint in the multivariable Cox model were HGF (P=0.004), C-reactive protein (P=0.007), and diabetes (P=0.04).

CONCLUSION

Our results demonstrate that in patients, without heparin pre-treatment, referred for PCR, a high serum level of HGF is an independent predictor of clinical events during follow-up and is correlated with other surrogate measures of the activity of atherosclerosis.

Plasma concentrations of adrenomedullin and ghrelin in hemodialysis patients with sustained and episodic hypotension

Sustained and/or episodic hypotension during hemodialysis (HD) is an important clinical issue. Plasma adrenomedullin (AM) is increased in HD patients with sustained hypotension, but little is known about its implications for episodic hypotension. Ghrelin may also contribute to the pathophysiology of hypotension in HD patients. We evaluated plasma levels of AM and total ghrelin in sustained hypotensive (SH; n = 23), episodic hypotensive (EH; n = 30) and normotensive (NT; n = 23) HD patients. In the EH group, the relationship between low blood pressure during HD and circulating levels of AM and ghrelin was also evaluated. Plasma levels of AM were significantly higher in SH (34.3 +/- 8.3 fmol/ml, p<0.01) than in NT patients (27.6 +/- 5.2 fmol/ml), but not in EH patients (30.8 +/- 6.1 fmol/ml). There was no significant difference of plasma total ghrelin in SH (548.1 +/- 426.5 fmol/ml) and in EH patients (544.6 +/- 174.3 fmol/ml), compared with NT patients (400.0 +/- 219.7 fmol/ml). On the other hand, in EH patients, the "suppressed blood pressure ratio" during HD significantly correlated with plasma AM (r = 0.77, p<0.001) and with total ghrelin levels (r = 0.44, p<0.05). Our results suggest that ghrelin, as well as AM, may play an important role as vasodilator local hormones and regulation of blood pressure during HD, especially the occurrence of EH. Further studies are necessary to clarify the implication of these hormones in the control of hypotension during HD.

Changes in common carotid artery intima-media thickness over 1 year in patients on peritoneal dialysis

BACKGROUND

Accelerated atherosclerosis and vascular calcifications increase cardiovascular morbidity and mortality in patients on dialysis. Common carotid artery (CCA) intima-media thickness (IMT) is considered useful for imaging atherosclerosis non-invasively. Since chronic inflammation may accelerate atherosclerosis in end-stage renal disease patients, the aim of this 1 year study was to assess changes in CCA-IMT in stable peritoneal dialysis (PD) patients, and to search for possible associations between these changes and selected cytokines, acute phase proteins and other risk factors of atherosclerosis.

METHODS

Of the original cohort of 61 stable patients on PD-28 female, 33 male; mean age 50.4+/-13.6 years; dialyse for a median of 17.5 months at inclusion (range 1-96 months)-47 patients survived the 1 year period on PD. CCA-IMT was assessed at baseline and after 12 months. Pro-inflammatory cytokines (IL-6, TNFalpha), acute phase proteins (CRP, fibrinogen), calcium-phosphate balance and lipid profile were assessed at baseline and after 6 and 12 months. Anthropometric parameters (age, weight, BMI, waist-to-hip ratio) were measured at baseline.

RESULTS

The mean CCA-IMT at baseline, 0.66+/- 0.19 mm, increased by a mean of 0.098+/-0.17 to 0.76+/-0.21 mm (P<0.001) in 1 year. In 14 patients (29.8%) at least one plaque was found in the CCAs examined. At the end of follow-up: 28 patients (59.6%) had increases in CCA-IMT (from 0.63+/-0.2 to 0.83+/- 0.21 mm; P = 0.03), and 19 (40.4%) remained stable or even showed slight, but non-significant, decreases of CCA-IMT (from 0.72+/-0.17 to 0.66+/-0.17 mm, P = NS). The 'progressors' had significantly higher initial BMI (P<0.05), and mean concentrations of calcium (P = 0.005), IL-6 (P = 0.05), TNFalpha (P = 0.05), CRP (P = 0.005) and lower HDL-cholesterol than 'non-progressors'. In univariate analysis, DeltaCCA-IMT correlated positively with age (R = 0.32, P = 0.03), BMI (R = 0.29, P = 0.05) and mean concentrations of CRP (R = 0.37, P = 0.01), TNFalpha (0.52, P = 0.0002), but inversely with HDL-cholesterol (R = -0.37, P = 0.01). In multiple regression analysis, however, only age appeared to be independently associated with increase in CCA-IMT (beta = 0.37, P<0.01; R(2) for the model 0.14).

CONCLUSIONS

Our results suggest a possible role of non-specific inflammation in the progression of atherosclerosis in patients treated with PD, in addition to age.

Significance of serum circulating hepatocyte growth factor in the development of carotid atherosclerosis

We investigated the relation between the serum concentration of HGF and carotid atherosclerosis. Serum concentrations of HGF were measured in 128 in-patients (mean age, 74 +/- 11 years) free from cardiac, liver and renal diseases, in addition to lung diseases, in the Medical Department of Nomura Municipal Hospital between August, 2000 and June, 2001. Carotid intima-media thickness (IMT) was evaluated by ultrasonography with a 7.5 MHz linear type B-mode probe. The results showed a significantly positive correlation between serum age and HGF concentrations in patients with carotid atherosclerosis (IMT > 1.0 mm) (r = 0.391, p = 0.005). On the other hand, there was no significant correlation between age and serum HGF concentration in those without carotid atherosclerosis (IMT </= 1.0 mm) (r = 0.157, p = 0.173). A general linear model analysis for HGF adjusted with other risk factors showed that the age-carotid atherosclerosis interactions were significantly associated with serum HGF (F [1.114] = 6.193; p = 0.014), in addition to age, systolic blood pressure (SBP), aniti-hypertensive drug use, diabetes mellitus and carotid atherosclerosis. In contrast, multiple regression analysis showed that serum HGF (beta = 0.160, p = 0.033) was independently associated with carotid atherosclerois, in addition to gender, age, SBP and HDL-cholesterol. These results suggest that increased serum HGF concentrations were associated with carotid atherosclerosis, independent of known risk factors for atherosclerosis.

Activation of hepatocyte growth factor/activin A/follistatin system during hemodialysis: Role of heparin

BACKGROUND

Hepatocyte growth factor (HGF), activin A, and follistatin compose an organotrophic system that may be modulated by heparin. We prospectively studied the effects of unfractionated heparin (UFH) versus low-molecular-weight heparin (LMWH) enoxaparin-anticoagulated hemodialysis on plasma levels of the cytokines.

METHODS

The factors were measured by immunoassays in 25 chronic hemodialysis patients at the start and at 10 and 180 minutes of the hemodialysis procedure anticoagulated with bolus enoxaparin. Then, the patients were randomized to either receive a bolus and infusion of UFH or to continue LMWH, and were reexamined after 12 weeks.

RESULTS

Predialysis HGF and follistatin were increased (both P < 0.0001), while activin A was normal in hemodialysis patients. Baseline HGF directly correlated with activin A in hemodialysis subjects (P=0.004). In healthy controls, it was positively associated with follistatin (P=0.001). Both HGF and activin A were markedly increased at each interval of enoxaparin-anticoagulated hemodialysis, and follistatin was increased at 10 minutes (all P < 0.0001). The early increments in HGF and follistatin directly depended on the dose of enoxaparin (both P < 0.030). Remarkably, the rise in activin A was inversely associated with the predialysis level of the cytokine (P < 0.0001). The actions of UFH resembled those of LMWH, although the releasing effects on the growth factors were not dose-dependent. The switch from LMWH to UFH resulted in a significant increase in over-dialysis HGF, a fall in follistatin, and no change in activin A.

CONCLUSION

HGF/activin A/follistatin system is activated and disturbed in chronic hemodialysis patients, including depletion of tissue stores of activin A. Type and dose of heparin used during hemodialysis procedures profoundly influence this pleiotropic system, and may thus modulate vital body functions and course of critical diseases.

Association of low fetuin-A (AHSG) concentrations in serum with cardiovascular mortality in patients on dialysis: a cross-sectional study

BACKGROUND

Vascular calcification is the most prominent underlying pathological finding in patients with uraemia, and is a predictor of mortality in this population. Fetuin-A (alpha2-Heremans Schmid glycoprotein; AHSG) is an important circulating inhibitor of calcification in vivo, and is downregulated during the acute-phase response. We aimed to investigate the hypothesis that AHSG deficiency is directly related to uraemic vascular calcification.

METHODS

We did a cross-sectional study in 312 stable patients on haemodialysis to analyse the inter-relation of AHSG and C-reactive protein (CRP) and their predictive effect on all-cause and cardiovascular mortality, over a period of 32 months. Subsequently, we tested the capacity of serum to inhibit CaxPO4 precipitation in patients on long-term dialysis (n=17) with apparent soft-tissue calcifications, and in those on short-term dialysis (n=8) without evidence of calcifications and cardiovascular disease.

FINDINGS

AHSG concentrations in serum were significantly lower in patients on haemodialysis (mean 0.66 g/L [SD 0.28]) than in healthy controls (0.72 [0.19]). Low concentrations of the glycoprotein were associated with raised amounts of CRP and with enhanced cardiovascular (p=0.031) and all-cause mortality (p=0.0013). Sera from patients on long-term dialysis with low AHSG concentrations showed impaired ex-vivo capacity to inhibit CaxPO4 precipitation (mean IC50: 9.0 microL serum [SD 3.1] vs 7.5 [0.8] in short-term patients and 6.4 [2.6] in controls). Reconstitution of sera with purified AHSG returned this impairment to normal. Interpretation AHSG deficiency is associated with inflammation and links vascular calcification to mortality in patients on dialysis. Activated acute-phase response and AHSG deficiency might account for accelerated atherosclerosis in uraemia.

Anaemia, cardiovascular disease and kidney disease: integrating new knowledge in 2002

PURPOSE OF REVIEW

The present review assesses recent publications, from 2001 until the present, which address the relationship between cardiovascular disease (CVD) and anaemia in patients with chronic kidney disease.

RECENT FINDINGS

Insights from the recently published basic science literature have helped to place findings from clinical studies into a new context, and thereby assist us to understand and further explore the complex relationship between haemoglobin level and survival in chronic kidney disease. The effects of erythropoietin molecules and the presence of receptors in vascular endothelium, myocardium and other tissues are described. Both observational and interventional clinical studies are examined, and limitations in the methodology and statistical analysis of clinical studies are emphasized, but are given context within the body of literature preceding the past year's publications.

SUMMARY

Data suggest that development of CVD in patients with kidney disease is multifactorial. Several factors associated with CVD are also associated with anaemia, thereby making causal arguments for the role of anaemia in CVD and survival difficult. Arguments are made for the importance of prevention of anaemia and of individualizing therapeutic goals for its treatment. Well designed prospective studies with both CVD events and mortality as outcomes, and with enrollment beginning before the start of dialysis, are essential if we are to determine the optimal therapeutic strategies.

An association between aortic pulse wave velocity, blood pressure and chronic inflammation in ESRD patients on peritoneal dialysis

Increased aortic pulse wave velocity (AoPWV) has been identified as a risk factor for cardiovascular morbidity in the general population and in patients on dialysis. Most of the studies in ESRD patients refer to subjects on hemodialysis. Influence of the inflammatory process on aortic stiffening remains largely unknown. The aim of the present study was to evaluate potential relationships between AoPWV and blood pressure, basic anthropometric parameters, selected growth factors and markers of the inflammatory process in ESRD patients treated with peritoneal dialysis. The study population consisted of 43 patients (19 F, 24 M) with a mean age of 50.6 +/- 13.4 years on PD for a mean period of 21.9 +/- 20.7 months. AoPWV was measured using two pressure transducers placed on the carotid and femoral arteries and connected to an automatic processor (Complion Colson AS, Paris, France). Serum levels of Tumor Necrosis Factor alpha (TNFalpha), interleukin 6 (IL-6) and plasma basic Fibroblast Growth Factor (bFGF) were measured with ELISA; C-reactive protein and fibrinogen with nephelometry. Serum lipid profile was also assessed. Blood pressure was measured in an outpatient department under standardized conditions. Mean aortic pulse wave velocity in the study population was 10.7 +/- 2.1 m/s. No difference in AoPWV was found between men and women. AoPWV correlated significantly with age (R = 0.41; p < 0.01) but not with time on dialysis. Positive relationship between AoPWV and body weight and BMI was shown (R = 0.31; p < 0.05 and R = 0.35; p < 0.05, respectively). AoPWV correlated significantly with systolic blood pressure (SBP), mean arterial pressure (MAP) and pulse pressure (PP) (R = 0.46, p < 0.005, R = 0.46, p < 0.005 and R = 0.43, p < 0.01, respectively). AoPWV correlated with serum IL-6 and plasma bFGF (R = 0.32, p < 0.05 and R = 0.4, p < 0.01; respectively). The correlation with serum CRP was borderline significant (p < 0.53). In multiple regression analysis age (beta 0.38; p < 0.005), plasma bFGF level (beta 0.3; p < 0.05), and systolic blood pressure (beta 0.29; p < 0.05) were independently associated with pulse wave velocity. Our results suggest that AoPWV values in patients on PD are associated with factors similar to those encountered in the general population. We suggest that increased aortic stiffening may also be related to the chronic inflammatory process in PD patients.

An association between coronary artery calcification score, lipid profile, and selected markers of chronic inflammation in ESRD patients treated with peritoneal dialysis

BACKGROUND

Chronic uremia is considered a proinflammatory state associated with high cardiovascular morbidity and mortality. The aim of the present study is to evaluate the potential relationship between the prevalence of coronary artery calcification (CAC) and selected factors that may be involved in the process of atherogenesis (lipid profile, acute-phase reactants, growth factors, and cytokines).

METHODS

The study group consisted of 43 patients (19 women, 24 men) with a mean age of 50.6 +/- 13.4 years treated with peritoneal dialysis (PD) for a median period of 15 months (range, 2 to 96 months). Only patients with sinus rhythm were included. CAC score (CaSc) was measured using multirow spiral computed tomography (MSCT). As parameters of lipid profile, total cholesterol, low-density lipoprotein (LDL) cholesterol, high-density lipoprotein (HDL) cholesterol, and triglycerides were assayed. C-reactive protein (CRP) and fibrinogen represented the level of acute-phase activation. Proinflammatory cytokines (interleukin-6 [IL-6] and tumor necrosis factor-alpha [TNF-alpha]), leptin, and basic fibroblast growth factor (bFGF) also were measured.

RESULTS

Median CaSc equaled 17.9 Agatston units (range, 0 to 5,502 Agatston units). No calcification was detected in 20 subjects (46.5%; CaSc < 10 Agatston units). CaSc correlated with age (R = 0.57; P < 0.0001), body mass index (R = 0.42; P < 0.005), and serum leptin (R = 0.3; P < 0.05) and CRP levels (R = 0.38; P < 0.05). The correlation with PD therapy duration was borderline statistically significant (P = 0.063). Patients with the greatest values for CaSc (> 400 Agatston units) were characterized by significantly greater levels of IL-6, bFGF, and CRP compared with subjects with a CaSc less than 10 Agatston units (P < 0.05 for all). Patients with history of coronary artery disease (CAD) had significantly greater CaSc values (median, 778.6 versus 3.3 Agatston units; P < 0.001) compared with those without CAD. Serum triglyceride levels were significantly greater and HDL cholesterol levels were significantly lower in patients with CAD. The first group also was characterized by significantly greater serum TNF-alpha (P < 0.01) and CRP levels (P < 0.005). In multiple regression analysis, only age was independently associated with CaSc (beta = 0.45; P = 0.002).

CONCLUSION

Our results may suggest an association between CAC and chronic inflammation activity in the mentioned group of patients. To our knowledge, this is the first study reporting the prevalence of CAC in PD patients using the MSCT method. The association between CaSc results and classic, as well as inflammatory, risk factors for CAD found in this study should be interpreted with caution because of its method limitations (cross-sectional design, heterogeneity of study population, and small number of studied patients).

Hepatocyte growth factor and left ventricular geometry in end-stage renal disease

Hepatocyte growth factor is a pleiotropic cytokine with cardioprotective properties. Its serum concentration is markedly raised in end-stage renal disease. This study assessed the relation of hepatocyte growth factor (HGF) with left ventricular mass and geometry in end-stage renal disease. Serum HGF measurements and echocardiographic studies were performed in 185 patients receiving hemodialysis. Patients with serum HGF above the median (1.85 ng/mL) had more frequent cardiovascular complications. This cytokine was directly related to mean left ventricular wall thickness (r=0.23, P=0.002) and relative wall thickness (r=0.25, P=0.0001); a multivariate analysis showed that this relation was independent of other risk factors. Accordingly, the prevalence of left ventricular concentric geometry (either concentric left ventricular hypertrophy or remodeling) was much higher (n=49, 53%) among patients with HGF values above the median that in those with values < or =1.85 ng/mL (n=31, 34%). Furthermore, the risk for left ventricular concentric geometry was higher in patients with HGF values above the median (odds ratio, 2.57; 95% CI, 1.33 to 4.98; P=0.005), and multiple logistic regression analysis confirmed that this association was independent of other risk factors. In patients receiving hemodialysis, elevated serum HGF is associated with concentric left ventricular geometry. This is consistent with reports that link this cytokine to arterial remodeling and survival in patients with end-stage renal disease and suggests that it is part of a counterregulatory response aimed at attenuating cardiovascular damage in this high-risk population.

Relations between oxidative stress, hepatocyte growth factor, and liver disease in hemodialysis patients

BACKGROUND

Hepatocyte growth factor (HGF) and copper/zinc superoxide dismutase (Cu/Zn SOD) protect against tissue injury, including that due to oxidative stress (SOX). We studied whether they could be associated with each other, SOX markers, prevalence of viral hepatitis, and cardiovascular disease (CVD) and their laboratory surrogates in maintenance hemodialysis (HD) patients.

METHODS

In 24 patients, pre-dialysis serum HGF, plasma Cu/Zn SOD, total lipid peroxides, and serum autoantibodies against oxidized LDL were measured by ELISAs. Viral hepatitis B and C markers were determined by third generation microparticle ELISAs, and CVD was identified on a clinical basis.

RESULTS

In HD patients, circulating HGF, Cu/Zn SOD, and the other SOX markers were higher than in healthy controls, and HGF directly correlated with Cu/Zn SOD levels (P = 0.0006). Both HGF (P = 0.021) and Cu/Zn SOD (P=0.017) were positively associated with prevalence of viral hepatitis and serum alanine aminotransferase activity (P = 0.021 and P=0.040, respectively). Presence of CVD directly correlated with HGF (P = 0.001) but not with Cu/Zn SOD levels (P = 0.087). Circulating HGF positively related to serum C-reactive protein (P = 0.043). In patients without viral hepatitis and CVD, both HGF and Cu/Zn SOD were lower than in those with, and higher than in healthy controls. CVD (P = 0.003) and viral hepatitis (P = 0.024) were independent predictors of increased HGF, while positive viral hepatitis marker predicted increased Cu/Zn SOD levels (P = 0.019) in HD patients. There were no associations between HGF and the SOX markers in controls.

CONCLUSIONS

In maintenance HD patients, circulating Cu/Zn SOD and HGF levels are increased, likely as a part of the reparatory reaction against liver damage. Viral hepatitis status and liver function should be considered in further studies of Cu/Zn SOD in these subjects.

Plasma hepatocyte growth factor and the relationship between risk factors and carotid atherosclerosis

Hepatocyte growth factor (HGF) has been shown to have a unique stimulating property on the endothelium as well as an anti-apoptotic action on the endothelium. Through these mechanisms, HGF has been shown to have an anti-atherogenic action in animal models. In atherosclerotic disorders, the circulating level of HGF has been shown to be increased to compensate for its decline in tissue. However, whether increased circulating HGF has any influence on the development of atherosclerosis has not been elucidated. In the present study, the association between plasma HGF concentration and the risk factor-carotid atherosclerosis relationship was evaluated. Three hundred and seventeen community-dwelling subjects participated in the study. The plasma concentration of HGF was determined by enzyme-linked immunosorbent assay (ELISA). The subjects were divided into two groups according to the plasma level of HGF: a low HGF group (n=199, plasma HGF < 150 pg/ml) and a high HGF group (n=118, plasma HGF > or = 150 pg/ml). Risk factors for atherosclerosis were evaluated in each subject. Carotid ultrasonography was performed to measure carotid arterial intima-media thickness (IMT) and the presence of plaque. The association between carotid IMT and risk factors was then evaluated in the two HGF groups. The regression lines between age and carotid IMT were significantly different between the low HGF and high HGF groups (F[1,313]=5.98, p=0.015). The regression lines between systolic blood pressure and carotid IMT were also significantly different between the two HGF groups (F[1,313]=5.17, p=0.024). A general linear model showed that the interaction between age and plasma level of HGF was significantly associated with carotid IMT, suggesting that the plasma level of HGF modifies the age-related increase in carotid IMT. In addition, clustering of risk factors was evaluated in subjects with carotid atherosclerosis. The number of total risk factors in carotid atherosclerosis subjects with high plasma HGF was significantly greater than that in those with low HGF, even though the two groups had a similar magnitude of carotid atherosclerosis. In conclusion, these findings indicate that risk factor-dependent augmentation of carotid atherosclerosis could be influenced by circulating HGF.

Advanced atherosclerosis in predialysis patients with chronic renal failure

BACKGROUND

Atherosclerosis is advanced in hemodialysis patients as shown by increased intima-media thickness of carotid arteries (CA-IMT), although it is not established whether the advanced atherosclerosis results from hemodialysis treatment or from chronic renal failure. The purpose of this study was to evaluate the effects of hemodialysis and renal failure on CA-IMT in patients with chronic renal failure.

METHODS

CA-IMT was measured by high-resolution B-mode ultrasonography in 110 patients with chronic renal failure before starting dialysis (CRF group), and compared with CA-IMT of 345 hemodialysis patients (HD group) and 302 healthy control subjects. They were all nondiabetic and the three groups were comparable in age and gender.

RESULTS

As compared with the healthy control subjects, the CRF and HD groups had greater CA-IMTs, whereas CA-IMTs of the CRF and HD groups were not statistically different. There was no significant correlation between duration of hemodialysis and CA-IMT in the HD group. Multiple regression analysis in the total subjects indicated that presence of renal failure, but not being treated with hemodialysis, was a significant factor associated with increased CA-IMT independent of age, gender, blood pressure, smoking, high-density lipoprotein (HDL) and non-HDL cholesterol levels.

CONCLUSIONS

These results demonstrate that thickening of arterial wall is present in patients with chronic renal failure before starting hemodialysis treatment, and support the concept that advanced atherosclerosis in hemodialysis patients is due not to hemodialysis treatment, but to renal failure and/or metabolic abnormalities secondary to renal failure.

Serum hepatocyte growth factor is associated with viral hepatitis, cardiovascular disease, erythropoietin treatment, and type of heparin in haemodialysis patients

BACKGROUND

Increased serum hepatocyte growth factor (HGF) level is a part of the counter-system against tissue damage and predicts mortality in maintenance haemodialysis (HD) patients. We studied which of the common co-morbid and clinical conditions, and surrogates of metabolic disorders or specific organ damage determine HGF levels in these subjects.

METHODS

In 86 patients, pre-dialysis serum HGF, soluble endothelial markers--such as thrombomodulin (TM), von Willebrand factor and plasminogen activator inhibitor-1--and hepatitis B and C markers were measured by ELISAs. Inflammatory reactants such as C-reactive protein (CRP), alpha(1)-antitrypsin, alpha(1) acid-glycoprotein, and immunoglobulin M and G were assayed by nephelometry, and lipoprotein(a) was determined by ELISA. Cardiovascular disease (CVD) was identified on a clinical basis.

RESULTS

Serum HGF was directly associated with the presence of viral hepatitis, alanine aminotransferase and TM levels, time on HD, the presence of CVD, CRP and alpha(1)-antitrypsin levels, use of unfractionated heparin (UFH) (vs enoxaparin) during HD, dose of UFH, use of recombinant erythropoietin (rHuEpo) treatment, and Kt/V. In 36 patients not treated with rHuEpo, HGF directly correlated with haemoglobin, but not with endogenous Epo levels. There was no association between HGF and the other endothelial and inflammatory markers, gender, age, smoking, cause of renal failure, body mass index, normalized protein catabolic rate, dialysate buffers, dialysers, blood pressure, antihypertensive treatment, leukocyte and platelet counts, albumin, fibrinogen, lipoprotein(a), markers of iron and calcium-phosphorus metabolism, or metabolic acidosis. Positive viral hepatitis markers, prevalent CVD and rHuEpo treatment (in descending order of significance) were independent predictors of high HGF level. In another 20 HD patients, a 4-week course of rHuEpo treatment resulted in a significant 17% increase in circulating HGF levels.

CONCLUSION

Serum HGF levels in HD patients are determined by inflammatory conditions such as viral hepatitis and CVD, increase in response to rHuEpo treatment, and may be influenced by type and dose of heparin used during HD procedures.

Association between carotid arterial remodeling and plasma concentration of circulating hepatocyte growth factor

BACKGROUND

Several studies have reported that the circulating concentration of hepatocyte growth factor (HGF) was increased in individuals with clinically overt atherosclerotic disease, including coronary heart disease and peripheral arterial disease. However, whether changes in the circulating concentration of HGF are associated with early atherosclerotic changes in apparently healthy individuals remains to be determined.

OBJECTIVE

To investigate the relationship between the plasma concentration of HGF and carotid arterial remodeling.

METHODS

Plasma concentrations of HGF were measured in 201 community-dwelling healthy residents free from any medications and signs and history of cardiovascular disease. Carotid intima-media thickness (IMT) and carotid internal diameter were determined by ultrasonography with a 7.5 MHz probe. The study participants were divided into four groups according to the presence or absence of carotid atherosclerosis (presence of plaque, IMT > or = 0.85 mm) and carotid arterial dilatation (diameter > or = 7.0 mm).

RESULTS

Carotid arterial remodeling, atherosclerosis or dilatation, or combinations thereof, was associated with significantly greater concentrations of plasma HGF. Among risk factors, plasma HGF was significantly associated with advanced age (> or = 65 years), current smoking and diabetes mellitus, whereas sex, obesity, hypertension and hypercholesterolemia did not affect plasma concentrations of HGF. Multiple regression analysis showed that plasma HGF was independently associated with carotid arterial remodeling (atherosclerosis, dilatation, or both) in addition to age and systolic blood pressure.

CONCLUSIONS

These results indicate that the plasma concentration of HGF increases in relation to carotid arterial remodeling, independently of known risk factors for atherosclerosis. These findings further support a possible role of HGF in atherosclerosis.

NUTRITIONALMANAGEMENT OFMAINTENANCEDIALYSISPATIENTS: Why Aren't We Doing Better?

About 40% of patients undergoing maintenance dialysis suffer from varying degrees of protein-energy malnutrition. This is a problem of substantial importance because many measures of nutritional status correlate with the risk of morbidity and mortality. There are many causes of protein-energy malnutrition in maintenance dialysis patients. Evidence indicates that nutritional decline begins even when the reduction in glomerular filtration rate is modest, and it is likely that the observed decrease in dietary protein and energy intake plays an important role. The nutrient intake of patients receiving maintenance dialysis also is often inadequate, and several lines of evidence suggest that toxins that accumulate with renal failure suppress appetite and contribute to nutritional decline once patients are on maintenance dialysis. Recent epidemiologic studies have suggested that both increased serum levels of leptin and inflammation may reduce nutrient intake and contribute to the development of protein-energy malnutrition. It is likely that associated illnesses, which are highly prevalent, contribute to malnutrition in maintenance dialysis patients. Recent data from the United States Renal Data System registry suggest that in the United States, the mortality rate of dialysis patients is improving. However, it remains high. We offer suggestions for predialysis and dialysis care of these patients that can result in improvement in their nutritional status. Whether this improvement will result in a decrease in patient morbidity and mortality is unknown.