[Serum troponin-I as a marker of fibroblast growth factor-23 (FGF-23) cardiotoxic effect, in patients with chronic kidney disease].

AIM: It has been established that an increased fibroblast growth factor (FGF-23) serum levels significantly contribute to the heart and blood vessels remodeling in patients with chronic kidney disease (CKD). But the precise mechanisms of the FGF-23 cardiac effect are currently being actively studied. At the same time, it is believed that the cardiac effects of FGF-23 may be due to the increasing deficit of Klotho protein as CKD progresses. In parallel with these changes, a number of studies indicate the persistence of the detectable troponins serum levels in CKD patients, even in the absence of clear clinical manifestations of cardiovascular diseases (CVD). The aim of the study was to confirm / exclude the existence of a causal relationship between elevated FGF-23, reduced Klotho and elevated troponin-I (as the most specific troponin in CKD). MATERIALS AND METHODS: The study included 130 CKD stages 1-5D patients without clinically pronounced symptoms of СVD (Coronary artery disease, CCS class 2-4, Chronic heart failure, NYHA 24, myocarditis, pericarditis, arrhythmias), as well as the severe arterial hypertension (BP >160/90 mm Hg), according to the laboratory and instrumental methods of examination. The selected group of patients was studied: serum levels of FGF-23 (Human FGF-23 ELISA kit), Klotho (Human soluble Klotho with antiklotho monoclonal antibodies), troponin-I (high - sensitive assay), and also data from instrumental examination methods: electrocardiography (ECG), echocardiography (left ventricular myocardial mass index (LVMI), cardiac (valvular) calcification score (CCS) using a semi - quantitative point scale), sphygmagraphy (augmentation (stiffness) indices of vessels (AI), pulse wave velocity (PWV), central (aortic) blood pressure (CBP), blood supply of subendocardium (BSE) - using "Shygmacor" device (Australia)). RESULTS AND DISCUSSION: The changes in serum levels of FGF-23, Klotho and troponin-I (Tr-I) depended on the stage of CKD. The following correlations were identified: FGF-23 and: Tr-I (r=0.601; p.

Fibroblast growth factor-23 (FGF-23) / soluble Klotho protein (sKlotho) / sclerostin glycoprotein ratio disturbance is a novel risk factor for cardiovascular complications in ESRD patients receiving treatment with regular hemodialysis or hemodiafiltration.

AIM: Aim of the study was to explore the role of the FGF-23/sKlotho/sclerostin ratio disturbance in the determining of cardiovascular risk in end stage renal disease (ESRD) patients, receiving treatment with regular hemodialysis (НD) or hemodiafiltration (НDF) online in Russia. MATERIALS AND METHODS: 42 patients with ESRD, at the age of 18-55 years, treated with HD or HDF on line for at least 6 months, were examined. 22 (52.3%) patients received traditional HD, the remaining 20 (47.7%) - HDF online. In all the patients, in addition to a general examination, the serum levels of FGF-23, sKlotho, sclerostine (by ELISA), their associations with cardiovascular risk factors (left ventricular hypertrophy (LVH), acute coronary syndrome (ACS), serum troponin I levels) with the numbers of techniques (ECG; Eho-CGF (with calculation of left ventricular myocardium mass index (LVMMI), as well as the relative thickness of the walls of the left ventricle (RWT); sphygmography (central (aortal) blood pressure (CBP), subendocardial blood flow (SBF) - by «Sphygmocor¼), and the effect of regular HD and HDF on serum levels of the studied markers, were assessed. RESULTS: An independent effect of FGF-23 on the risk of LVH, as well as on the increase of serum troponin I in the studied ESRD patients [ß=3.576 p<0.01, and ß=1.115, p<0.05, respectively] was found. Serum Klotho was the factor most associated with the CBP [ß=-0.023; p<0.001]. The increased serum sclerostin was correlated with a lower incidence of both reduced SBF [r=0.492; p<0.05], symptoms of coronary heart disease [r=-0.449; p<0.05] and rhythm disturbances [r=-0.446; p<0.05]. In addition, in HD patients higher FGF-23 and lower Klotho and sclerostine serum levels were associated with: inadequate dialysis syndrome (Kt/V <1.1; r=0.463; p<0.05), chronic inflammation (C-reactive protein >10 mg/L; r=0.612; p<0.01), and with a decrease in serum albumin level (<35 g/l; r=0.459; p<0.05). The FGF-23/sKlotho/sclerostin ratio disturbance was more pronounced in patients treated with traditional HD then HDF online. A direct correlation (r=0.445; p<0.05) was established between FGF-23 serum levels and serum phosphorus, which was more pronounced in HD patients (r=0.545; p<0.01). CONCLUSION: In HD and HDF ESRD patients, higher serum FGF-23 and lower sKlotho and sclerostin levels were associated with a chronic inflammation, malnutrition, secondary hyperparathyroidism, and may considered as predictors of cardiovascular complications such as LVH, ACS, rhythm disturbances, persisting of subincreased serum troponin I.

Quality of life of chronic kidney disease patients on renal replacement therapy.

The study demonstrated the results of the comparative analysis of various types of renal replacement therapy effects on the quality of life patients with terminal stage of chronic kidney disease on the basis of standardized questionnaires. It has been shown that the quality of life is significantly improved after a kidney transplantation. At the same time, it has also been found that the introduction of home dialysis, epoetins, active metabolites of vitamin D, calcimimetics in the clinic care expanded the opportunities for the labor rehabilitation of the dialysis patients and made their quality of life comparable with the same of the kidney transplant recipients.

[Effects of keto/amino acids and a low-protein diet on the nutritional status of patients with Stages 3B-4 chronic kidney disease]. / Vliianie keto/aminokislot i ogranicheniia belka na status pitaniia bol'nykh khronicheskoi bolezn'iu pochek IIIB-IV stadii.

AIM: To evaluate the efficacy of keto/amino acids in maintaining protein balance and preventing mineral metabolic disturbances and the development of uremic hyperparathyroidism in the long-term use of a low-protein diet (LPD) in patients with Stages 3B-4 chronic kidney disease (CKD). SUBJECTS AND METHODS: Ninety patients with CKD caused by chronic latent glomerulonephritis in 65 patients and chronic tubulointerstitial nephritis of various etiologies (gout, drug-induced, and infection) in 25 were examined. The investigators conducted clinical, laboratory, and instrumental examinations, including bioelectrical impedance analysis (body mass index (BMI), the percentages of lean and fat mass), echocardiography and radiography of the abdominal aorta in the lateral projection (the presence of cardiac valvular and aortic calcification), and pulse wave velocity measurements using a Sphygmocor apparatus (vessel stiffness estimation). The stages of CKD were defined according to the 2012 Kidney Disease: Improving Global Outcomes (KDIGO) criteria; glomerular filtration rate was calculated using the CKD EPI equation. According to the diet used, all the patients were divided into 3 groups: 1) 30 patients who took LPD (0.6 g of protein per kg of body weight/day) in combination with the keto/amino acid ketosteril (1 tablet per 5 kg of body weight/day; Diet One); 2) 30 patients who used LPD in combination with the other keto/amino acid ketoaminol at the same dose (Diet Two); 3) 30 patients had LPD without using the keto/amino acids (Diet Three) (a control group). RESULTS: During a follow-up, there were no signs of malnutrition in Groups 1 and 2 patients receiving LPD (0.6 g protein per kg/day) in combination with the keto/amino acids ketosteril and ketaminol, respectively. At the same time, 11 (36.6%) patients in Group 3 (a control group) who did not take the keto/amino acids showed a BMI decrease from 24 (23; 26) kg/m2 to 18.5 (17; 19.2) kg/m2 (p < 0.05), including that of lean body mass from 37.4 (36; 38.8) to 30 (29.1; 34.7)% in the men (p<0.05) and from 29.8 (26.8; 31) to 23.9 (22; 25.7)% in the women (p<0.01). In addition, at the end of the study, there were elevated serum phosphorus levels (p<0.05) and mainly higher parathyroid hormone concentrations in Group 3 patients who received LPD without using the amino/keto acids than in Groups 1 and 2. As compared to Group 3, Groups 1 and 2 displayed no differences in the quantity of cardiac and aortic calcification and in the augmentation index (arterial stiffness). The ketosteril and ketaminol groups versus the control group had also higher s-Klotho levels (p<0.01) that were inversely correlated with glomerular filtration rate (r =-0.467; p<0.01). CONCLUSION: The keto/amino acids ketosteril or ketoaminol are an important component of LPD, which prevents malnutrition and an additional source of calcium that inhibits hyperphosphatemia and slows the development of uremic hyperparathyroidism. Incorporation of keto/amino acids into LPD leads to a less pronounced reduction in s-Klotho protein in relation to the degree of renal failure than does LPD without keto/amino acids.

[The serum level of the morphogenetic protein fibroblast growth factor 23 (FGF-23) as a marker for the efficiency of hyperphosphatemia therapy with phosphate-binding agents in chronic kidney disease]. / Uroven' morfogeneticheskogo belka - faktora rosta fibroblastov 23-go tipa (FGF-23) v syvorotke krovi kak marker effektivnosti terapii giperfosfatemii svyazyvayushchimi fosfat preparatami pri khronicheskoi bolezni pochek.

AIM: To study whether the excessive production of serum fibroblast growth factor 23 (FGF-23) may be reduced with phosphate-binding agents to treat hyperphosphatemia in patients with Stage VD chronic kidney disease (CKD). MATERIALS AND METHODS: The investigation enrolled 25 patients with Stage VD CKD on regular hemodialysis (HD) (12 patients with chronic glomerulonephritis, 8 with tubulointerstitial nephritis, and 5 with hypertensive nephrosclerosis); among them there were 15 men and 10 women at the age of 21 to 65 years; their mean age at inclusion in the study was 43±4.5 years. The clinical, laboratory, and instrumental examination similar to that in patients with the early stages of CKD was done. Serum FGF-23 levels (Human FGF-23 ELISA kit using monoclonal antibodies to the full FGF-23 molecule) were investigated in all the 25 patients. A whole blood sample was taken 2 days after the last session of HD before initiation of its regular procedure. RESULTS: The elevated serum FGF-23 concentrations in the patients on regular HD correlated with their HD duration (r=0.508; p<0.001). Along with this, a strong direct correlation (r=0.522; p<0.001) was found between the concentration of FGF-23 in the serum and inorganic phosphorus; at the same time hyperphosphatemia was less significantly associated with higher serum intact parathyroid hormone (PTH) levels (r=0.398; p<0.05). Lower FGF-23 and PHT levels were noted in a group of patients who could achieve and maintain the target serum inorganic phosphorus level (0.9-1.45 mmol/l) compared to that of patients with uncorrected hyperphosphatemia (>1.45 mmol/l) (p<0.01). A decrease in FGF-23 and PHT levels was achieved chiefly in the patients who had used phosphate-binders that contained no calcium (sevelamer hydrochloride). CONCLUSION: Lower FGF-23 levels were observed in the patients with CHD on regular HD who can achieve and maintain the target serum inorganic phosphorus level when using phosphate-binders that do not contain calcium than in those with uncorrected hyperphosphatemia (p<0.01).

[Alterations of the complement system in patients with catastrophic antiphospholipid syndrome].

AIM: To investigate alterations of the complement system in patients with catastrophic antiphospholipid syndrome (CAPS). SUBJECTS AND METHODS: Four patients (2 men aged 23 and 40 years and 2 women aged 39 and 58 years) diagnosed as having CAPS, including 3 patients with systemic lupus erythematosus and secondary antiphospholipid syndrome (APS) and 1 patient with primary APS, were examined. The activity of the complement components C1-C5 and total hemolytic activity were determined in all the patients at the moment of an acute episode and in 1 patient after treatment. RESULTS: The activity of the studied complement components and total hemolytic complement activity proved to be significantly decreased in all the patients. That of complement components recovered after treatment using fresh frozen plasma. The possibility and mechanisms of complement system activation in the patients with CAPS are discussed. CONCLUSION: The preliminary results obtained by the examination of few cases may lead to the conclusion that the complement system may be involved in the development of CAPS.

[Experience with active vitamin D metabolites in phosphorus-calcium metabolic disorders in patients with predialysis chronic kidney disease].

AIM: To evaluate the efficacy and safety of alfacalcidol and paracalcitol used to correct impaired phosphorus-calcium metabolism (PCM) in patients with predialysis chronic kidney disease (CKD). SUBJECTS AND METHODS: Examinations were made in 128 patients with Stages III-V CKD, including 89 (69.5%) patients with chronic glomerulonephritis, 30 (23.4%) with chronic tubulointerstitial nephritis, and 9 (7.1%) with hypertensive nephrosclerosis. Impaired PCM was detected in 90 (70.3%) of the examined patients. According to the pattern of the previous therapy, all the 90 CKD patients with PCM disorders were divided into 3 groups: 1) 32 patients with Stages IIIB-V CKD who had taken oral alfacalcidol 0.25 microg/day; 2) 28 patients with Stages IIIB-V CKD who had used oral paricalcitol 1 microg/day; 3) 30 patients with Stages IIIB-V CKD who had not received, as self- motivated, active vitamin D metabolites at the predialysis stage. RESULTS: Alfacalcidol and paricalcitol were quite satisfactorily tolerated by the patients. After 3 months of initiation of the use of these agents, Groups 1 and 2 patients with predialysis CKD and baseline elevated blood intact parathyroid hormone (iPTH) levels could not only achieve, but also maintain target blood iPTH levels. In the patients taking paricalcitol, the urinary protein level decreased more promptly; moreover, by the end of month 6 the reduction in blood pressure (BP) was more significant than in those using alfacalcidol (p < 0.05). Comparison of the effects of angiotensin-converting enzyme inhibitors in combination with alfacalcidol or paricalcitol on BP changes and left ventricular mass index indicated that the most pronounced positive changes occurred when angiotensin-converting enzyme inhibitors were used in combination with paricalcitol. CONCLUSION: The use of paricalcitol in predialysis CKD with PTH hyperproduction results in not only normalization of the levels of both PTH and osseous isoenzyme of alkaline phosphatase, but also in significantly reduced daily proteinuria and regression of left ventricular hypertrophy and chronic heart failure.

[Mechanisms of phosphorus and calcium homeostatic disorders in the development of cardiovascular events in patients with chronic renal diseases. The role of fibroblast growth factor 23 and Klotho].

The paper deals with the analysis of studies of the role of the bone morphogenetic proteins fibroblast growth factor 23 (FGF-23) and Klothno in the development of vascular wall calcification in chronic renal disease (CRD). FGF-23 is shown to be an important phosphaturic hormone that inhibits hypercalcemic and hyperphosphatemic effects of elevated serum vitamin D concentrations. There is evidence that there is an association between high serum FGF-23 levels and vascular wall calcification irrespective of the content of phosphorus and parathyroid hormone. Most authors regard FGF-23 as a potential uremic toxin in patients with end-stage CRD. There are data that support the renoprotective value of the morphogenetic protein Klotho whose expression in CRD is decreased.

[The role of balanced low-protein diet in inhibition of predialysis chronic kidney disease progression in patients with systemic diseases].

AIM: To evaluate the effects of low-protein diet (LPD) balanced by addition of highly energetic mix and essential keto/amino acids on inhibition of renal failure in patients with systemic diseases with predialysis stages of chronic disease of the kidney (CDK). MATERIAL AND METHODS: Forty six patients with stage III--IV of CDK in systemic diseases (33 SLE patients and 13 with systemic vasculitis) were randomized into three groups. Group 1 consisted of 18 patients with CDK (10 with stage III and 8 with stage IV). They received LPD (0.6 g/kg/day) with addition of essential keto/amino acids for 24-48 months. Group 2 of 18 CDK patients with the same stages received the same diet but greater amount of vegetable protein (highly purified soya protein) to 0.3 g/kg/day in highly energetic nutrient mixture. Group 3--10 CDK patients (7 with stage III and 3 with stage IV) received free diet. Group 1 and 2 patients received LPD irrespective of the nutrient status assessed basing on anthropometric and other data. Protein consumption and caloric value were estimated by 3-day food diary. RESULTS: Before diet therapy, out of 46 examinees nutrient status was abnormal in 45.7% patients. Both variants of LPD were well tolerated and nutrient status was corrected while the rate of nutritive disorders in group 3 increased 1.5-fold (from 40 to 60%) with progression of renal failure. Intake of LPD diet for at least a year reduced glomerular filtration rate inhibition, especially in addition of highly energetic mixture. CONCLUSION: Early (predialysis) restriction of diet protein (0.6 g/kg/day) with addition of highly energetic mixture and essential keto/amino acids improves a nutritive status of CDK patients and inhibits GFR decline.