The Efficacy, the Treatment Response and the Aquaretic Effects of a Three-Year Tolvaptan Regimen in Polycystic Kidney Disease Patients.

Tolvaptan, a selective vasopressin V2 receptor antagonist, is the first and only approved specific treatment for Autosomal-Dominant Polycystic Kidney Disease (ADPKD), and is used in current clinical practice. Real clinical data are missing. In this retrospective study, 41 ADPKD patients received tolvaptan for 3 years, from 2018 to 2021. Total kidney volume (TKV) was measured using Magnetic Resonance Imaging, at initiation and at the end of the treatment period. A complete biochemistry/hematology profile and a 24 h urine volume collection were performed monthly for the first 18 months and every 3 months thereafter. At the end of the treatment period, the median (IQR) estimated Glomerular Filtration Rate (e-GFR) was 5.3 (-1.3, 8.7) mL/min higher than the expected e-GFR decline without treatment, while the prediction for End Stage Chronic Kidney Disease (ESKD) had been prolonged by 1 (0, 2) year. Total Kidney Volume did not change significantly (2250 (1357) mL at 3 years of treatment vs. 2180 (1091) mL expected without treatment, p = 0.48). Younger patients with a relatively preserved e-GFR, lower hypertension burden, better familiar renal prognosis and more severe imaging data showed better outcomes. The aquaretic adverse effects of tolvaptan did not affect renal function and electrolyte balance in 51 patients, in a follow-up period of 18 months. Consequently, tolvaptan seems to be effective in preventing progression of ADPKD when administered in a timely manner in patients with better familiar renal history, shorter hypertension duration and worse imaging profile. Increased diuresis does not affect treatment efficacy.

Is there a connection between inflammation, telomerase activity and the transcriptional status of telomerase reverse transcriptase in renal failure?

Telomerase is involved in the elongation of telomeres. It remains active in very few types of cell in mature organisms. One such cell type is the lymphocytes. In this study, we investigated the activity and expression of telomerase in lymphocytes from renal failure patients and compared it to that for normal controls. Inflammation status was determined at the same time. The enzyme activity was measured using PCR-ELISA with peripheral blood mononuclear cells (PBMCs) from three groups: 53 healthy individuals, 50 patients with chronic kidney disease (CKD) and 50 dialysis patients. In the same cell populations, the expression of the reverse transcriptase of the human telomerase gene (hTERT) was measured via real-time PCR. The inflammationstatus of these individuals was determined by calculating the interleukin 6 (IL-6), IL-10, C-reactive protein (CRP) and tumor necrosis factor alpha (TNF-a) serum concentrations via ELISA. The lowest levels of telomerase activity were detected in CKD, and this group had the highest IL-6 and CRP values and the lowest hTERT expression. The dialysis group showed significant differences in comparison to the normal subjects and to the CKD patients. Further studies are warranted in order to explore the way inflammation influences telomerase activity and hTERT expression.

Serum hepcidin levels are associated with serum triglycerides and interleukin-6 concentrations in patients with end-stage renal disease.

Hepcidin has emerged as a peptide with a key role in the regulation of iron homeostasis in patients with chronic kidney disease (CKD), having a strong dependence on inflammation. Recent studies reveal that hepcidin may be also associated with the progression of atherosclerosis. This study was performed to analyze the relation of hepcidin to markers of atherosclerosis and inflammation in patients on dialysis. A total of 90 individuals were enrolled. Sixty patients with end-stage renal disease, who were on hemodialysis (HD) (N = 30) and peritoneal dialysis (N = 30) were compared with 30 normal controls (NC). Age, body mass index, time on dialysis, serum lipids, C-reactive protein (CRP) and interleukin-6 (IL-6) were measured and analyzed in correlation with hepcidin concentration. It was found that patients on HD and peritoneal dialysis have significantly higher (P < 0.0001) levels of hepcidin, CRP and IL-6 than NC. Hepcidin in dialysis patients is significantly related to age (r = 0.373, P = 0.012), serum triglycerides (r = 0.401, P = 0.005), HDL-C (r = -0.268, P = 0.048), CRP (r = 0.436, P = 0.0007) and IL-6 (r = 0.569, P < 0.0001). In multiple regression analysis, hepcidin correlated independently with triglycerides (ß = 0.402, P = 0.041) and IL-6 (ß = 0.559, P = 0.006). Moreover, patients with high triglycerides in combination with high IL-6 levels have significantly increased concentrations of hepcidin than those with low triglycerides and low IL-6 levels (P < 0.0001). Elevated levels of hepcidin in patients with CKD on dialysis may be related to the occurrence of high triglycerides and high IL-6 serum concentrations. This probably suggests that hepcidin may play a role to the progression of atherosclerosis and inflammation, but this hypothesis should be further evaluated.

Transcription of the Tumor Suppressor Genes p53 and RB in Lymphocytes from Patients with Chronic Kidney Disease: Evidence of Molecular Senescence?

Patients suffering from renal failure exhibit an impaired immune system function. We wanted to investigate the transcription of the tumor suppressor genes p53 and RB to record, if these cells could be stimulated in vitro in order to divide, after the addition of antigenic and inflammatory factors. This expression was measured by real-time PCR in peripheral blood mononuclear cells (PBMCs) from three different groups: ten healthy individuals, ten patients with chronic kidney disease (CKD), and ten dialysis patients with end stage renal disease (ESRD). The transcription rate of these genes was also measured after the cultivation of PBMCs under four different conditions: just with the culture medium, with lipopolysaccharide (LPS), with C-reactive protein (CRP), and with lipoxin A(4) (LXA(4))-LPS. Our results show that in most cases after the cultivation with additives, the transcription levels were higher in dialysis patients compared to those of the other two groups. Our findings serve as indications of cellular senescence on a molecular level, while it seems that these cells are less easily stimulated in vitro in order to duplicate.

Myocardial performance index suggests optimal fluid loss during hemodialysis.

BACKGROUND: Patients on long-term maintenance hemodialysis (HD) are at high risk of developing cardiovascular disease and suffering various cardiovascular complications during HD. HYPOTHESIS: The purpose of this study was to evaluate the influence of changing loading conditions on the myocardial performance index (MPI) in patients on long-term HD and to specify an optimal level of fluid loss during HD that would maintain stable global cardiac function. METHODS: The study consisted of 52 patients with end-stage renal failure (ESRF), mean age 56±11.7 y, range: 25-80 y, on regular HD. For each patient a complete echocardiographic-Doppler examination was performed before and after HD. Systolic and diastolic parameters of left ventricular function were measured, and the myocardial performance index (MPI) was calculated. RESULTS: The MPI was significantly prolonged after HD (0.47±0.15 before HD versus 0.59±0.16 after HD, p < 0.001). Mean change in body weight during HD was 2.1±0.86 kg. The MPI did not change significantly in patients with intradialytic weight loss up to 1.75 kg. CONCLUSIONS: The MPI value seems to be independent of acute preload changes only when fluid loss is less than 1.75 kg. A 1.75-kg fluid loss during HD seems to be the optimal goal. In ESRF patients on HD, the MPI seems to be a good indicator of global left ventricular function and potentially a valuable aid in the effort to maintain optimal fluid balance.

Low cholesterol along with inflammation predicts morbidity and mortality in hemodialysis patients.

Low and not high cholesterol seems to predict high mortality in hemodialysis (HD) patients. The confirmation of this reverse epidemiology as well as its possible interconnection with the increased inflammatory activity observed in this population is being explored in the present study. A group of 136 HD patients was prospectively studied for 2 years, and cardiovascular disease (CVD) as well as all-cause mortality and morbidity were recorded. Baseline lipid profile, inflammatory status, and patients' characteristics were studied as potential survival and hospitalization predictors. During the 24-month follow-up, 21 deaths (52.4% due to CVD) and 38 hospitalizations (55.3% due to CVD) were recorded. In multivariate Cox regression analysis, decreased interleukin-10 (IL-10) and decreased total serum cholesterol (TChol) were the only independent predictors of CVD mortality while C-reactive protein and decreased TChol predicted all-cause mortality. Interleukin-10 at baseline was 11.29 +/- 21.49 vs. 5.51 +/- 4.57 pg/mL (P<0.018) and TChol 167.37 +/- 47.84 vs.122.04 +/- 26.48 mg/dL (P<0.000) in survivors vs. nonsurvivors from CVD, while C-reactive protein at baseline was 9.37 +/- 11.54 vs. 23.15 +/- 18.76 mg/L (P<0.000) and TChol 169.26 +/- 46.42 vs. 133.26 +/- 46.33 mg/dL (P<0.003) in survivors vs. nonsurvivors from any cause of death. Using the same method of statistical analysis, IL-6 and decreased soluble gp130 (sgp130)--an antagonist of IL-6 action--were found to be the only independent prognostic factors for hospitalization due to CVD while decreased soluble gp130 remained the sole predictor of hospitalization due to any cause. In conclusion, reverse epidemiology regarding cholesterol is confirmed in the present study. Furthermore, inflammatory activity also predicts, independently of or in conjunction with low-cholesterol, CVD and all-cause morbidity and mortality in HD patients.

Cellular senescence and inflammation: a noteworthy link.

Although cellular senescence and inflammation have been indirectly associated, a direct connection was absent until recently, when two studies proved that senescence at a cellular level is directly linked to an interleukin (IL)-dependent inflammatory network. IL-6 and IL-8, two well-known proinflammatory cytokines, seem to play a central role in premature cellular senescence induction. Activation of the above-mentioned molecules and their receptors is necessary for the initiation of senescence while their deactivation ceases the process. Taking in consideration that atherosclerosis is an inflammatory process and cellular senescence is an emerging cardiovascular risk factor, these new data may be of great importance, especially for chronic kidney disease patients who suffer from increased cardiovascular disease morbidity.

Cellular senescence, cardiovascular risk, and CKD: a review of established and hypothetical interconnections.

Cellular senescence is associated with shortened or damaged telomeres and is characterized by permanent exit from the cell cycle, morphological changes, and altered function. It develops after repeated cell divisions and also can be induced prematurely by stress conditions. The senescent phenotype, depending on cell type and atherosclerosis phase, seems to be a proatherosclerotic one: it promotes endothelial dysfunction and appears to be implicated in plaque destabilization, as well as in endothelial progenitor cell alteration. Many traditional and nontraditional cardiovascular disease risk factors induce senescence in a variety of vascular cells. Several of these factors, such as diabetes, hypertension, oxidative stress, and inflammation, are clustered in patients with chronic kidney disease. In a limited number of recent studies, stress-induced premature cellular senescence in this biologically aged population also was described. The hypothesis that premature cellular senescence might be considered an additional atherosclerosis-inducing factor in patients with chronic kidney disease is proposed.

Is inflammation the link between atherosclerosis and vascular calcification in chronic kidney disease?

Atherosclerosis and vascular calcification often co-exist in chronic kidney disease (CKD) patients. Although the former has been recently recognized as an active inflammatory process, atherosclerosis-related calcification of the intima is still viewed as a passive epiphenomenon. Recent experimental data showed that ossification of the internal vascular wall might also be an active inflammatory process interrelated to atherosclerosis. Factors like RANKL (receptor activator of nuclear factor kappaB ligand), RANK and osteoprotegerin modulate vascular calcification and at the same time are involved in the process of atherosclerosis. Moreover, basic calcium phosphate crystals could interact with and activate monocytes-macrophages that produce proinflammatory cytokines capable of initiating - via endothelial activation and leukocyte adhesion - the atherosclerotic process. Thus, vascular calcification might be an active player and not simply an epiphenomenon in atherosclerosis. Should the above-mentioned data be confirmed in future studies, calcification of the internal vascular wall and atherosclerosis might be viewed and treated as tightly interconnected and linked by inflammation processes in CKD patients.

Telomerase activity is decreased in peripheral blood mononuclear cells of hemodialysis patients.

BACKGROUND: Telomerase preserves telomere length and structure, preventing cellular senescence, which is associated with alteration of the chromosomal ends. We hypothesized that telomerase activity is altered in peripheral blood mononuclear cells (PBMCs) of hemodialysis (HD) patients. To investigate this hypothesis as well as the relationship between telomerase and inflammation, we measured the activity of this reverse transcriptase as well as the level of several inflammatory markers in PBMCs and serum of an end-stage renal failure (ESRF) population and a non-renal-failure group of subjects. METHODS: In PBMCs isolated from 42 HD and 39 non-renal-failure subjects of the same age (51.0 +/- 12.4 and 51.4 +/- 12.1 years, respectively) telomerase activity was measured using PCR-ELISA; the method was based on the telomeric repeat amplification protocol. RESULTS: Telomerase activity in PBMCs was detected in 18 (42.9%) HD and 28 (71.8%) non-renal-failure subjects (p = 0.013). Among positive subjects, percent telomerase activity in PBMCs was significantly higher in non-renal- failure (117 +/- 112 %) than in HD (47.6 +/- 57.1 %) subjects (p = 0.008). Detectable telomerase activity was lower in long-term than in short-term HD patients (13.3 +/- 8.9 vs. 75.0 +/- 64.8%, respectively, p = 0.015). Although higher in HD group, inflammatory indexes (C-reactive protein, interleukin-6, IL-6, soluble IL-6 and soluble gp130) were not correlated to telomerase activity in PBMCs. CONCLUSION: Telomerase activity in PBMCs is reduced in HD patients. It seems that, at least in this type of cell in this population, defense from senescence, as assessed by telomerase activity, is altered and associated with the chronicity of uremia/HD procedure.

Serum oxidized low-density lipoprotein is inversely correlated to telomerase activity in peripheral blood mononuclear cells of haemodialysis patients.

BACKGROUND: Telomerase preserves telomeres' function and structure preventing cellular senescence. Its activity is reduced in peripheral blood mononuclear cells (PBMC) of haemodialysis (HD) patients. The purpose of this study is to investigate the potential correlation between increased oxidative stress/inflammation and telomerase activity in PBMC of HD patients. METHODS: Telomerase activity was measured by PCR-ELISA in PBMC isolated from a group of 42 HD patients and 39 subjects with estimated glomerular filtration rate >or=80 mL/min (control group). Serum oxidized low-density lipoprotein (ox-LDL), tumour necrosis factor-alpha (TNF-alpha) and interleukin-10 (IL-10) were also measured in both groups by ELISA. RESULTS: Ox-LDL was negatively correlated to percentage telomerase activity in PBMC (r = -0.506, P = 0.000 in the whole group of 81 HD and normal subjects and r = -0.559, P < 0.001 in HD patients). TNF was also inversely associated with percentage telomerase activity in the whole group studied (r = -0.492, P = 0.000) while IL-10 was not. In stepwise multiple linear regression, taking into consideration the most important characteristics of the HD patients and control group, the only significant predictors for percentage telomerase activity in PBMC were ox-LDL and TNF (beta = -0.421, t = -4.083, P = 0.000 and beta = -0.381, t = -3.691, P = 0.000, respectively) while examining separately HD patients, the predictors for the same parameter were ox-LDL and HD duration (beta = -0.671, t = -4.709, P = 0.000 and beta = -0.349, t = -2.447, P = 0.023, respectively). CONCLUSION: Ox-LDL serum level is inversely correlated to telomerase activity in PBMC of HD patients. Our study proposes a new consequence of increased oxidative stress in HD patients: the premature cellular senescence potentially related to atherosclerosis through LDL oxidation.

Release of interleukin-6 and its soluble receptors by activated peripheral blood monocytes is elevated in hypocholesterolemic hemodialysis patients.

BACKGROUND: A reverse association between cholesterol level and cardiovascular disease mortality is observed in hemodialysis (HD) patients; this paradoxical relationship may be explained by the coexistence of inflammation. Interleukin-6 (IL-6) is a central regulator of inflammation; its action is augmented by the soluble IL-6 receptor (sIL-6R) and inhibited by the soluble gp130 (sgp130). In order to investigate the potential association of inflammation with cholesterol levels in the HD population, release of soluble IL-6 components by peripheral blood mononuclear cells (PBMCs) was measured in two groups of HD patients with distinctly different lipid profile and in a control group. METHODS: Twenty-two HD patients with low serum cholesterol (range 85-171 mg/dl), 23 HD patients with high cholesterol (189-342 mg/dl) and 21 normolipidemic non-renal failure subjects were enrolled in the study. IL-6, sIL-6R and sgp130 were measured by ELISA in the serum and in the supernatant collected from cell cultures of activated or resting PBMCs isolated from all three groups. RESULTS: Serum IL-6 and sgp130 level was higher while sIL-6R was lower in both groups of HD patients compared to the control group. The ex-vivo release of the IL-6 and sgp130 by unstimulated PBMCs did not differ significantly between the three groups but that of the sIL-6R was higher in non-renal failure than in hypercholesterolemic HD subjects. Production of sIL-6R by stimulated PBMCs was higher in low-cholesterol HD patients (p < 0.001) and the same was valid for the sgp130 release (p = 0.034). Release of IL-6 by activated PBMCs was higher in the low-cholesterol compared to the high-cholesterol HD patients group (p = 0.011 for post hoc test). Major serum lipid fractions were inversely correlated to IL-6 and sIL-6R production from stimulated PBMCs in HD but not in non-renal failure subjects. Finally, release of the sgp130 by PBMCs was significantly reduced in 13 hypertriglyceridemic--and hypercholesterolemic--HD patients. CONCLUSION: Production of soluble components of a crucial pro-inflammatory and potentially atherogenic cytokine, namely the IL-6, by stimulated PBMCs appears to be inversely correlated with the serum cholesterol levels in HD patients.

Inflammation in atherosclerosis and other conditions: a response to danger.

In the last few years atherosclerosis has been recognized as an inflammatory process. Assessment of low-grade inflammation with indexes like C-reactive protein (CRP) is considered indicative and potentially predictive for this disease. On the other hand, in a large number of clinical studies, a grade of microinflammation has been found to be associated with numerous other processes that may be directly, indirectly or not related to atherosclerosis. The most interesting finding these studies have yielded is that innate immunity is activated in various, previously unexpected, conditions. This phenomenon is better explained by the application of a recently proposed immune activation mechanism, namely, the 'danger model'. It seems that many conditions related to metabolic or homeostatic stress or to pro-atherosclerotic and pre-diabetic dysfunctions, established atherosclerosis or diabetes, but also other early tissue injury -- like renal, pulmonary or connective tissue -- and several exogenous stimuli, constitute 'danger signals' that induce inflammation which interacts with and complicates the above-mentioned processes. On this basis the complex relationships between CVD risk factors, atherosclerotic process, other tissue injury and inflammation is examined. The practical application of this hypothesis, namely the new clinical use of CRP as a sensitive -- although not specific for atherosclerosis -- index of low-grade inflammatory activity as well as to the atherosclerosis treatment are also discussed.

Serum and peripheral blood mononuclear cells infectious burden: correlation to inflammation and atherosclerosis in haemodialysis patients.

BACKGROUND: Infectious agents may be implicated in the inflammatory atherosclerotic process. Not only specific microorganisms but also the infectious burden, defined as the number of pathogens to which a patient is exposed, has been associated with atherosclerosis. In the present study, the infectious burden, determined directly (by identification of viable pathogens in peripheral blood mononuclear cells (PBMC)) and indirectly (by serum antibodies detection) is correlated to the inflammatory and atherosclerotic status in haemodialysis (HD) patients, a population at high risk for cardiovascular disease. METHODS: The viable forms of four microorganisms (Chlamydia pneumoniae, herpes virus 1 and 2 and cytomegalovirus) were identified in patients PBMC by cell cultures and subsequent polymerase chain reaction. Serum IgG against the above pathogens and Helicobacter pylori were also determined. Inflammation was assessed by measurement of C-reactive protein (CRP), serum amyloid A (SAA), three pro- and one anti-inflammatory cytokines and four adhesion molecules. Atherosclerosis was defined by a scoring system using medical history data. RESULTS: The number of viable pathogens identified in PBMC in the 122 HD patients included in the study were zero in 22.1% of them, one in 33.6%, two in 43.4% and three in one patient. The number of IgG antibodies determined was one in 6.6% of patients, two in 32%, three in 48.4% and four in 13.1%. Seropositivity was not significantly different between patients with or without the respective viable pathogen identified in PBMC. Atherosclerosis was present in 40.2% of patients, and CRP, SAA and interleukin-6 were all increased in these patients. Neither inflammatory indexes nor atherosclerosis were significantly different in patients with a higher number of viable pathogens detected in PBMC or in those with a higher antibodies number. CONCLUSIONS: The direct infectious burden determination (the number of viable pathogens in PBMC) does not coincide with the serum (by IgG detection) infectious burden. Although inflammation correlates to atherosclerosis, neither PBMC nor the serum infectious burden is associated with these two entities in the inflamed and atherosclerotic HD patients.

Catastrophic antiphospholipid syndrome in a 14-year-old child.

Antiphospholipid syndrome (APS) is an autoimmune disease. Less than 1% of patients with APS present with life-threatening catastrophic APS (CAPS). We report here a case of CAPS in a young girl with cardiac, gastrointestinal and renal involvement. Although the management was complicated, the outcome was better than expected. We suggest that CAPS be included in the differential diagnosis of acute renal failure in children with multi-organ involvement and prolonged phospholipid-dependent coagulation time and promptly treated with immunomodulating agents and anticoagulants.