Age-Related Changes in Clinical and Analytical Variables in Chronic Hemodialyzed Patients.

Worldwide, the number of elderly individuals receiving chronic hemodialysis is rising. The aim of our study was to evaluate several clinical and analytical biomarkers in chronically dialyzed patients and analyze how they change with age. A cross-sectional study was performed by evaluating 289 end-stage renal disease patients undergoing dialysis. We evaluated the hemogram, adipokines, the lipid profile, and several markers related to inflammation, endothelial function/fibrinolysis, nutrition, iron metabolism, and cardiac and renal fibrosis. Clinical data and dialysis efficacy parameters were obtained from all patients. The relationships between studied biomarkers and age were assessed by a statistical comparison between younger (adults with age < 65 years) and older (age ≥ 65 years) patients and by performing regression analysis. Participants presented a mean age of 68.7 years (±13.6), with 66.8% (n = 193) being classified as older. Compared to younger patients, older patients presented the following: (a) significantly lower values of diastolic blood pressure (DBP) and ultrafiltration volume; (b) lower levels of phosphorus, uric acid, creatinine, and albumin; and (c) higher circulating concentrations of tissue-type plasminogen activator (tPA), D-dimer, interleukin-6, leptin, N-terminal pro B-type natriuretic peptide, and tissue inhibitor of metalloproteinase-1. In the multiple linear regression analysis, DBP values, tPA, phosphorus, and D-dimer levels were independently associated with the age of patients (standardized betas: -0.407, 0.272, -0.230, and 0.197, respectively; p < 0.001 for all), demonstrating relevant changes in biomarkers with increasing age at cardiovascular and nutritional levels. These findings seem to result from crosstalk mechanisms between aging and chronic kidney disease.

Inflammatory biomarkers in staging of chronic kidney disease: elevated TNFR2 levels accompanies renal function decline.

BACKGROUND: Inflammation is a common feature in the pathogenesis of chronic kidney disease (CKD), regardless of the disease cause. Our aim was to evaluate the potential of several inflammatory biomarkers in CKD diagnosis and staging. METHODS: A total of 24 healthy controls and 92 pre-dialysis CKD patients with diverse etiologies, were enrolled in this study and grouped according to their CKD stage. We analysed the circulating levels of inflammatory molecules, C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), tumor necrosis factor receptor 2 (TNFR2), pentraxin 3 (PTX3) and leptin, as well as the hemogram. We studied their association with parameters of kidney function and kidney injury, to evaluate their potential as early markers of the disease and/or of its worsening, as well as their interplay. RESULTS: Compared to controls, patients in CKD stages 1-2 presented significantly higher IL-6 and TNFR2 levels, and higher neutrophil-to-lymphocyte ratio. All inflammatory cytokines and acute-phase proteins showed a trend to increase up to stage 3, stabilizing or declining thereafter, save for TNFR2, which steadily increased from stage to stage. All inflammatory molecules, apart from PTX3, were negatively and significantly correlated with eGFR, with a remarkable value for TNFR2 (r = - 0.732, p < 0.001). CONCLUSION: TNFR2 might be useful for an early detection of CKD, as well as for disease staging/worsening. Still, the potential value of this biomarker in disease progression warrants further investigation.

Long Pentraxin 3 as a Broader Biomarker for Multiple Risk Factors in End-Stage Renal Disease: Association with All-Cause Mortality.

Persistent inflammation in end-stage renal disease (ESRD) patients is known to underlie the progression of chronic kidney disease and to be associated with multiple risk factors including malnutrition, atherosclerosis, and cardiovascular disease (CVD). The acute-phase protein pentraxin 3 (PTX3) has a proven potential as a local inflammatory biomarker, but its clinical utility in ESRD remains unclear. Circulating levels of PTX3 and classical inflammatory mediators, including the clinical prototypical C-reactive protein (CRP), were assessed in 246 ESRD patients on dialysis and analysed in relation to the lipid profile, adipokine levels, and nutritional, cardiac, and renal fibrosis markers. Occurrence of deaths was recorded for the following year. Contrarily to the classical inflammatory markers, PTX3 levels were negatively correlated with nutritional markers and associated with a less atherogenic lipid profile. Levels of the cardiac and renal fibrosis markers and of the oxidized LDL/LDL-C ratio were found to be independent determinants of PTX3 concentration. When comparing inflammatory mediators, the increase in the PTX3 levels was the only predictor of all-cause mortality in dialysis patients in a survival model adjusted to all markers under study, other than the inflammatory ones, besides common confounding factors in dialysis. Data support the clinical applicability of PTX3 as a broader inflammatory biomarker than the classical ones, presenting a close association with inflammation, malnutrition, CVD, and renal fibrosis and a great potential to predict all-cause mortality in dialysis patients. The pleiotropic character of PTX3 may be of clinical relevance, and it could be targeted to ameliorate the high morbidity and mortality associated with ESRD.

Hepcidin and diabetes are independently related with soluble transferrin receptor levels in chronic dialysis patients.

Background: Soluble transferrin receptor (sTfR) is a biomarker of erythropoiesis, which is often impaired in dialysis patients. The aim of our study was to evaluate sTfR levels in chronically dialyzed patients and assess potential determinants of its levels. Methods: We performed a cross-sectional study by evaluating 246 end-stage renal disease patients undergoing dialysis and 32 healthy controls. Circulating levels of interleukin (IL)-6, C-reactive protein (CRP), tumor necrosis factor (TNF)-α, hepcidin, sTfR, growth differentiation factor 15 (GDF15), and traditional iron metabolism markers were measured, as well as hemogram parameters. Clinical data was obtained from all patients. Results: Compared to controls, patients presented similar values of sTfR, reticulocytes and reticulocyte production index (RPI), and significantly higher levels of IL-6, CRP, ferritin, hepcidin, TNF-α, and GDF15. Iron, transferrin, hemoglobin levels, erythrocyte count, mean cell hemoglobin (MCH), and mean cell hemoglobin concentration (MCHC) values were significantly lower in dialysis group. Within patients, sTfR values were higher in diabetic patients and were positively and significantly correlated with reticulocytes and erythrocytes, RPI, and therapeutic doses of erythropoiesis stimulating agents (ESA) and intravenous iron; and inversely and significantly correlated with circulating iron, ferritin, transferrin saturation, hepcidin, MCH, and MCHC. In multiple linear regression analysis, ESA dose, RPI, serum iron, diabetes, and hepcidin levels were independently associated with sTfR levels in dialysis patients and, thus, with erythropoiesis. Conclusion: Our data suggest that, besides RPI and ESA dose, diabetes and hepcidin are closely related to erythropoiesis in dialysis patients. The influence of diabetes on sTfR levels deserves further investigation.

Physical exercise intervention at school improved hepcidin, inflammation, and iron metabolism in overweight and obese children and adolescents.

BackgroundObesity is often associated with iron deficiency in children and adolescents. We aimed to study the effect of an 8-month physical exercise (PE) intervention on hepcidin and other markers of inflammation and on iron status in overweight/obese children and adolescents.MethodsSeventy-three overweight/obese children and adolescents participated in the 8-month-long longitudinal study. They were divided into two groups according to their participation in an after-school PE program: the PE group (n=44) and the control group (n=29). Hepcidin, interleukin (IL)-6, C-reactive protein (CRP), iron, ferritin, transferrin, and soluble transferrin receptor (sTfR) were evaluated.ResultsAt baseline, IL-6 correlated positively with hepcidin and negatively with iron and transferrin saturation, suggesting that increasing adiposity associates with increasing IL-6 and hepcidin synthesis, reducing iron availability. After 8 months, the PE group showed a decrease in BMI z-score (P=0.003), body fat mass (P=0.012), CRP (P=0.002), IL-6 (P=0.048), ferritin (P=0.013), hepcidin (P=0.040), and sTfR (P=0.010), and an increase in iron concentration (P=0.002). Moreover, the PE group, when compared with the control group, showed lower weight (P=0.026), BMI (P=0.040), waist circumference (P=0.010), and waist-to-height ratio (P=0.046).ConclusionWe showed that an 8-month-long intervention at school allowed a reduction in BMI z-score and an improvement in inflammation, reducing hepcidin levels and the disturbances in iron status.

Recombinant human erythropoietin-induced erythropoiesis regulates hepcidin expression over iron status in the rat.

The crosstalk between several factors controlling hepcidin synthesis is poorly clarified for different physiological and pathological conditions. Our aim was to study the impact of increasing recombinant human erythropoietin (rHuEPO) doses on erythropoiesis, iron metabolism and hepcidin, using a rat model. Male Wistar rats were divided in 5 groups: control (vehicle) and rHuEPO-treated groups (100, 200, 400 and 600IU/kgbody weight/week), 3 times per week, during 3weeks. Hematological and iron data were evaluated. The expression of several genes involved in iron metabolism was analyzed by qPCR. Liver hepcidin protein was evaluated by Western Blot. The rHuEPO treatment induced erythropoiesis and increased transferrin saturation (TSAT) in a dose dependent manner. Tf receptor 2 (TfR2), hemojuvelin (HJV) and bone morphogenetic protein 6 (BMP6) were up-regulated in rHuEPO200 group. Matriptase-2 was down-regulated in rHuEPO200 group, and up-regulated in the other rHuEPO-treated groups. Hepcidin synthesis was increased in rHuEPO200 group, and repressed in the rHuEPO400 and rHuEPO600 groups. Our study showed that when a high erythropoietic stimulus occurs, hepcidin synthesis is mainly regulated by TSAT; however, when the erythropoiesis rate reaches a specific threshold, extramedullary hematopoiesis is triggered, and the control of hepcidin synthesis is switched to matriptase-2, thus inhibiting hepcidin synthesis.

Renal risk-benefit determinants of recombinant human erythropoietin therapy in the remnant kidney rat model - hypertension, anaemia, inflammation and drug dose.

Clinical studies showed that high doses of recombinant human erythropoietin (rHuEPO) used to correct anaemia in chronic kidney disease (CKD) hyporesponsive patients may lead to deleterious effects. The aim of this study was to analyze the effects of rHuEPO in doses usually used to correct CKD-anaemia (100, 200 IU/kg body weight (BW) per week) and in higher doses used in the treatment of hyporesponsive patients (400, 600 IU/kg BW per week), focusing on renal damage, hypoxia, inflammation and fibrosis. Male Wistar rats with chronic renal failure (CRF) induced by 5/6 nephrectomy were treated with rHuEPO or with vehicle, over a 3-week period. Haematological, biochemical and renal function analyses were performed. Kidney and liver mRNA levels were evaluated by quantitative real-time polymerase chain reaction (qPCR) and protein expression by Western blot and immunohistochemistry. Kidney histopathological evaluations were also performed. The CRF group developed anaemia, hypertension and a high score of renal histopathologic lesions. Correction of anaemia was achieved with all rHuEPO doses, with improvement in hypertension, renal function and renal lesions. In addition, the higher rHuEPO doses also improved inflammation. Blood pressure was reduced in all rHuEPO-treated groups, compared to the CRF group, but increased in a dose-dependent manner. The current study showed that rHuEPO treatment corrected anaemia and improved urinary albumin excretion, particularly at lower doses. In addition, it is suggested that a short-term treatment with high doses, used to overcome an episode of hyporesponsiveness to rHuEPO therapy, can present benefits by reducing inflammation, without worsening of renal lesions; however, the pro-hypertensive effect should be considered, and carefully managed to avoid a negative cardiorenal impact.

Impact of a School-Based Intervention Protocol - ACORDA Project - On Adipokines in An Overweight and Obese Pediatric Population.

PURPOSE: There are few reliable studies assessing the effect of physical exercise (PE) on adipokines levels at young ages. Our objective was to study the effects of regular PE on plasma adipokines in pediatric overweight and obesity. METHOD: 117 overweight and obese children and adolescents (47% females; 10.2 years) participated in an 8-month longitudinal study divided in two groups: PE group (n = 80), engaged in an after-school PE program; control group (n = 37), with no PE program. Plasma lipids, C-reactive protein (CRP), adiponectin, resistin, leptin, IL-6, IL-1beta, TNF-alpha, insulin and glucose levels were determined. RESULTS: contrarily to the control group, the PE group presented reductions in body mass index z-score (BMIzsc) and body fat percentage that were accompanied by an improvement in lipid profile and insulin resistance, a reduction in CRP and TNF-alpha and an increase in adiponectin levels. The reductions in BMIzsc were inversely correlated with changes in adiponectin (r=-0.329, p = .003) and positively correlated with changes in percentage body fat (r = .262, p = .032), triglycerides (r = .228, p = .042) and leptin (r = .285, p = .010). CONCLUSIONS: Moderate reductions in adiposity improve proinflammatory status in obese children and adolescents. A more substantial reduction in BMIzsc was associated with a greater increment in adiponectin and reduction in leptin.

Resistance to Recombinant Human Erythropoietin Therapy in a Rat Model of Chronic Kidney Disease Associated Anemia.

This study aimed to elucidate the mechanisms explaining the persistence of anemia and resistance to recombinant human erythropoietin (rHuEPO) therapy in a rat model of chronic kidney disease (CKD)-associated anemia with formation of anti-rHuEPO antibodies. The remnant kidney rat model of CKD induced by 5/6 nephrectomy was used to test a long-term (nine weeks) high dose of rHuEPO (200 UI/kg bw/week) treatment. Hematological and biochemical parameters were evaluated as well as serum and tissue (kidney, liver and/or duodenum) protein and/or gene expression of mediators of erythropoiesis, iron metabolism and tissue hypoxia, inflammation, and fibrosis. Long-term treatment with a high rHuEPO dose is associated with development of resistance to therapy as a result of antibodies formation. In this condition, serum EPO levels are not deficient and iron availability is recovered by increased duodenal absorption. However, erythropoiesis is not stimulated, and the resistance to endogenous EPO effect and to rHuEPO therapy results from the development of a hypoxic, inflammatory and fibrotic milieu in the kidney tissue. This study provides new insights that could be important to ameliorate the current therapeutic strategies used to treat patients with CKD-associated anemia, in particular those that become resistant to rHuEPO therapy.

Adiponectin and markers of metabolic syndrome in obese children and adolescents: impact of 8-mo regular physical exercise program.

BACKGROUND: Adiponectin circulates as low-, medium-, and high-molecular-weight multimers (LMW, MMW, and HMW) and influences lipid profile and insulin resistance (IR), HMW being considered as the most biologically active form. We aimed to study the relation between adiponectin and markers of metabolic syndrome (MS) in pediatric obesity, and the impact of physical exercise. METHODS: The study consisted of a cross-sectional part and an 8-mo physical exercise program. Lipid profile, insulin, glucose, C-reactive protein (CRP), total adiponectin (TA), and homeostasis model assessment IR (HOMA-IR) were measured. Adiponectin multimers were studied in a prepubertal group. RESULTS: Obesity is associated with increased dyslipidemia, IR, and inflammation. TA is correlated inversely with adiposity, triglycerides, HOMA-IR, and CRP, and positively with high-density lipoprotein cholesterol (HDLc)/total cholesterol (TC) ratio. HMW mimicked TA associations. The intervention program led to a reduction of TC, low-density lipoprotein cholesterol (LDLc), insulin, HOMA-IR, and trunk percentage of fat, and an increase of HDLc/TC ratio, in the obese group. BMI improvements prevented adiponectin reduction and correlated with increments in HMW and MMW. CONCLUSION: Obesity-related increase in MS features might be linked to lower adiponectin. HMW and MMW were the multimers that most explained the MS features. The intervention program improved the lipid profile and IR, and prevented the reduction of adiponectin.

Transition from cyclosporine-induced renal dysfunction to nephrotoxicity in an in vivo rat model.

Cyclosporin A (CsA), a calcineurin inhibitor, remain the cornerstone of immunosuppressive regimens, regardless of nephrotoxicity, which depends on the duration of drug exposure. The mechanisms and biomarkers underlying the transition from CsA-induced renal dysfunction to nephrotoxicity deserve better elucidation, and would help clinical decisions. This study aimed to clarify these issues, using a rat model of short- and long-term CsA (5 mg/kg bw/day) treatments (3 and 9 weeks, respectively). Renal function was assessed on serum and urine; kidney tissue was used for histopathological characterization and gene and/or protein expression of markers of proliferation, fibrosis and inflammation. In the short-term, creatinine and blood urea nitrogen (BUN) levels increased and clearances decreased, accompanied by glomerular filtration rate (GFR) reduction, but without kidney lesions; at that stage, CsA exposure induced proliferating cell nuclear antigen (PCNA), transforming growth factor beta 1 (TGF-ß1), factor nuclear kappa B (NF-κß) and Tumor Protein P53 (TP53) kidney mRNA up-regulation. In the long-term treatment, renal dysfunction data was accompanied by glomerular and tubulointerstitial lesions, with remarkable kidney mRNA up-regulation of the mammalian target of rapamycin (mTOR) and the antigen identified by monoclonal antibody Ki-67 (Mki67), accompanied by mTOR protein overexpression. Transition from CsA-induced renal dysfunction to nephrotoxicity is accompanied by modification of molecular mechanisms and biomarkers, being mTOR one of the key players for kidney lesion evolution, thus suggesting, by mean of molecular evidences, that early CsA replacement by mTOR inhibitors is indeed the better therapeutic choice to prevent chronic allograft nephropathy.

Impact of TNFRSF1B (rs3397, rs1061624 and rs1061622) and IL6 (rs1800796, rs1800797 and rs1554606) Gene Polymorphisms on Inflammatory Response in Patients with End-Stage Kidney Disease Undergoing Dialysis.

We aimed to study the impact of polymorphisms in the genes encoding interleukin-6 (IL6) and tumor necrosis factor receptor-2 (TNFR2), reported to be mortality risk predictors, in patients with end-stage kidney disease (ESKD) undergoing dialysis. TNFRSF1B (rs3397, rs1061624, and rs1061622) and IL6 (rs1800796, rs1800797, and rs1554606) polymorphisms were studied in patients with ESKD and controls; the genotype and allele frequencies and the associations with inflammatory and erythropoiesis markers were determined; deaths were recorded throughout the following two years. The genotype and allele frequencies for the TNFRSF1B rs3397 polymorphism were different in these patients compared to those in the controls and the global and European populations, and patients with the C allele were less common. Patients with the CC genotype for TNFRSF1B rs3397 presented higher hemoglobin and erythrocyte counts and lower TNF-α levels, suggesting a more favorable inflammatory response that seems to be associated with erythropoiesis improvement. Patients with the GG genotype for TNFRSF1B rs1061622 showed lower serum ferritin levels. None of the TNFRSF1B (rs3397, rs1061624, and rs1061622) or IL6 (rs1800796, rs1800797, and rs1554606) polymorphisms had a significant impact on the all-cause mortality rate of Portuguese patients with ESKD.

The antiestrogen 4-hydroxytamoxifen protects against isotretinoin-induced permeability transition and bioenergetic dysfunction of liver mitochondria: comparison with tamoxifen.

The combination of isotretinoin (13-cis-retinoic acid) with antiestrogens seems to be a promising strategy for cancer chemotherapy. The aim of the study was to evaluate the effects of isotretinoin alone or in combination with 4-hydroxytamoxifen (OHTAM) and with its prodrug tamoxifen (TAM), on the functions of rat liver mitochondria, i.e., mitochondrial permeability transition (MPT), bioenergetic functions and adenine nucleotide translocase (ANT). Isotretinoin (5 nmol/mg protein) induced the Ca²âº-dependent MPT pore opening in mitochondria energized with succinate, which was prevented by OHTAM, cyclosporine A, TAM and ANT ligands. When mitochondria were energized with glutamate/malate and in the absence of added Ca²âº isotretinoin decreased the state 3 respiration, the ATP levels, the active ANT content and increased the lag phase of the phosphorylation cycle, demonstrating that isotretinoin decreased the mitochondrial phosphorylation efficiency. These changes of isotretinoin in bioenergetic parameters were not significant in the presence of succinate. The effects of isotretinoin at 5 nmol/mg protein on the Ca²âº-dependent MPT and phosphorylative efficacy may be related with interactions with the ANT. Above 10 nmol/mg protein isotretinoin strongly diminished the active ANT content, decreased the Δψ, inhibited the complex I and induced proton leak through the Fo fraction of complex V. The combination of OHTAM with isotretinoin only induced significant changes in the energy production systems at concentrations ≥5 nmol isotretinoin/mg protein. Therefore, our results suggest that isotretinoin-associated liver toxicity is possibly related with mitochondrial dysfunctions and that the combination with OHTAM may contribute to decrease its toxicity.

Implication of low HDL-c levels in patients with average LDL-c levels: a focus on oxidized LDL, large HDL subpopulation, and adiponectin.

To evaluate the impact of low levels of high density lipoprotein cholesterol (HDL-c) on patients with LDL-c average levels, focusing on oxidative, lipidic, and inflammatory profiles. Patients with cardiovascular risk factors (n = 169) and control subjects (n = 73) were divided into 2 subgroups, one of normal HDL-c and the other of low HDL-c levels. The following data was analyzed: BP, BMI, waist circumference and serum glucose Total-c, TGs, LDL-c, oxidized LDL, total HDL-c and subpopulations (small, intermediate, and large), paraoxonase-1 (PON1) activity, hsCRP, uric acid, TNF- α , adiponectin, VEGF, and iCAM1. In the control subgroup with low HDL-c levels, significantly higher values of BP and TGs and lower values of PON1 activity and adiponectin were found, versus control normal HDL-c subgroup. However, differences in patients' subgroups were clearly more pronounced. Indeed, low HDL-c subgroup presented increased HbA1c, TGs, non-HDL-c, Ox-LDL, hsCRP, VEGF, and small HDL-c and reduced adiponectin and large HDL. In addition, Ox-LDL, large-HDL-c, and adiponectin presented interesting correlations with classical and nonclassical markers, mainly in the normal HDL-c patients' subgroup. In conclusion, despite LDL-c average levels, low HDL-c concentrations seem to be associated with a poor cardiometabolic profile in a population with cardiovascular risk factors, which is better evidenced by traditional and nontraditional CV biomarkers, including Ox-LDL, large HDL-c, and adiponectin.

Body mass index and resistance to recombinant human erythropoietin therapy in maintenance hemodialysis patients.

The aim of this work was to contribute to a better understanding of the relationship between resistance to recombinant human erythropoietin (rhEPO) therapy and body mass index (BMI) in hemodialysis (HD) patients. We evaluated 191 HD patients and 25 healthy individuals. Complete blood count, reticulocyte count, and circulating levels of ferritin, transferrin, iron, soluble transferrin receptor (sTfR), transferrin saturation, hepcidin, C-reactive protein (CRP), interleukin 6 (IL-6), albumin, and adiponectin were measured in all patients and controls. Non-responder patients (n = 16), as compared with responder patients (n = 175), showed statistically significant lower BMI values, an enhanced inflammatory and higher adiponectin levels, associated with disturbances in iron metabolism. Analyzing the results according to BMI, we found that underweight patients required higher rhEPO doses than normal, overweight, and obese patients, and a higher percentage of non-responders patients were found within the underweight group of HD patients. Moreover, underweight patients presented lower levels of transferrin and higher levels of adiponectin compared to overweight and obese patients, and lower levels of iron compared with normal weight patients. Multiple regression analysis identified the sTfR, hemoglobin, BMI, and albumin as independent variables associated with rhEPO doses. In conclusion, our work showed that HD patients resistant to rhEPO therapy present a functional iron deficiency and a higher degree of inflammation, despite their lower BMI values and higher levels of adiponectin. Actually, BMI is poorly related with markers of systemic inflammation, such as IL-6 and CRP, while adiponectin works a fairly good indirect marker of adiposity within HD patients.

The Association of Leptin with Left Ventricular Hypertrophy in End-Stage Kidney Disease Patients on Dialysis.

Left ventricular hypertrophy (LVH) is a common cardiovascular complication in end-stage kidney disease (ESKD) patients. We aimed at studying the association of LVH with adiponectin and leptin levels, cardiovascular stress/injury biomarkers and nutritional status in these patients. We evaluated the LV mass (LVM) and calculated the LVM index (LVMI) in 196 ESKD patients on dialysis; the levels of hemoglobin, calcium, phosphorus, parathyroid hormone, albumin, adiponectin, leptin, N-terminal pro B-type natriuretic peptide (NT-proBNP) and growth differentiation factor (GDF)-15 were analyzed. ESKD patients with LVH (n = 131) presented higher NT-proBNP and GDF-15, lower hemoglobin and, after adjustment for gender, lower leptin levels compared with non-LVH patients. LVH females also showed lower leptin than the non-LVH female group. In the LVH group, LVMI presented a negative correlation with leptin and a positive correlation with NT-proBNP. Leptin emerged as an independent determinant of LVMI in both groups, and NT-proBNP in the LVH group. Low hemoglobin and leptin and increased calcium, NT-proBNP and dialysis vintage are associated with an increased risk of developing LVH. In ESKD patients on dialysis, LVH is associated with lower leptin values (especially in women), which are negatively correlated with LVMI, and with higher levels of biomarkers of myocardial stress/injury. Leptin and NT-proBNP appear as independent determinants of LVMI; dialysis vintage, hemoglobin, calcium, NT-proBNP and leptin emerged as predicting markers for LVH development. Further studies are needed to better understand the role of leptin in LVH in ESKD patients.

Main determinants of PON1 activity in hemodialysis patients.

BACKGROUND/AIMS: Cardiovascular diseases are the major cause of morbidity and mortality in hemodialysis (HD) patients. These patients present reduced paraoxonase 1 (PON1) activity that depends on genetic and non-genetic factors; however, how these factors influence PON1 activity in HD patients is poorly clarified. Our aim was to evaluate the influence of two polymorphisms and non-genetic factors on PON1 activity in HD patients. METHODS: We evaluated 183 HD patients under recombinant human erythropoietin (rhEPO) treatment and 22 healthy individuals. The lipid profile [total cholesterol, triglycerides, HDL-c, LDL-c, apolipoprotein (Apo) A-I, Apo B, lipoprotein(a) and oxidized low-density lipoprotein (Ox-LDL)], inflammatory markers [adiponectin, interleukin-6 (IL-6) and C-reactive protein (CRP)], PON1 activity and PON1 gene polymorphisms (L55M and Q192R) were evaluated. RESULTS: HD patients presented higher levels of IL-6, CRP and Ox-LDL/LDL-c, and lower PON1 activity, total cholesterol, HDL-c, LDL-c, Apo A and Apo B; the most frequent genotype was heterozygosity for L55M polymorphism and homozygosity for the Q allele, the more frequent genotype of Q192R polymorphism. Multiple regression analysis identified heterozygosity and homozygosity for L55M and Q192R polymorphisms, very low-density lipoproteins, LDL-c, Apo A and CRP levels, time on dialysis and rhEPO dose, as the independent variables significantly associated with PON1 activity. The associations with CRP, rhEPO and time on dialysis were negative. CONCLUSION: Our results show that the reduced PON1 activity in HD patients who are not under statin therapy is strongly associated with inflammation, longer time on dialysis and high rhEPO doses, suggesting that the reduction in PON1 activity may worsen the prognosis of these patients.

Adiponectin is an independent predictor of tissue plasminogen activator levels in patients under haemodialysis.

OBJECTIVE: The aim of this study was to evaluate the association of tissue-type plasminogen activator (t-PA) levels with clinical data of patients under haemodialysis (HD) and with several variables potentially related to endothelial function and dysfunction. MATERIAL AND METHODS: In a cross-sectional study involving 189 Portuguese HD patients, circulating levels of t-PA, lipids, oxidized low-density lipoprotein (Ox-LDL), interleukin-6 (IL-6), C-reactive protein (CRP), adiponectin, plasminogen activator inhibitor type 1 (PAI-1) and fibrin fragment D-dimer were measured. RESULTS: Considering the entire population, t-PA correlated inversely and significantly with adiponectin and high-density lipoprotein-cholesterol, and positively and significantly with age, body mass index, PAI-1, IL-6, CRP, D-dimer, cholesterol and Ox-LDL. In multiple linear regression analysis PAI-1, age and adiponectin remained statistically associated with t-PA values (p < 0.01 for all). The weakest significant association (p = 0.046) was that found between t-PA and D-dimer. CONCLUSION: Adiponectin is a main determinant of t-PA level, which may be a good marker of endothelial dysfunction in HD patients.

Chemopreventive efficacy of Atorvastatin against nitrosamine-induced rat bladder cancer: antioxidant, anti-proliferative and anti-inflammatory properties.

To investigate the anti-carcinogenic effects of Atorvastatin (Atorva) on a rat bladder carcinogenesis model with N-butyl-N-(4-hydroxibutil)nitrosamine (BBN), four male Wistar rat groups were studied: (1) CONTROL: vehicle; (2) Atorva: 3 mg/kg bw/day; (3) Carcinogen: BBN (0.05%); (4) Preventive Atorva: 3 mg/kg bw/day Atorva + BBN. A two phase protocol was used, in which the drug and the carcinogen were given between week 1 and 8 and tumor development or chemoprevention were expressed between week 9 and 20, when the bladders were collected for macroscopic, histological and immunohistochemical (p53, ki67, CD31) evaluation. Serum was assessed for markers of inflammation, proliferation and redox status. The incidence of bladder carcinoma was: control 0/8 (0%); Atorva 0/8 (0%); BBN 13/20 (65%) and Atorva + BBN 1/8 (12.5%). The number and volume of tumors were significantly lower in the Atorva + BBN group, with a marked reduction in hyperplasia, dysplasia and carcinoma in situ lesions. An anti-proliferative, anti-inflammatory and antioxidant profile was also observed in the preventive Atorva group. p53 and ki67 immunostaining were significantly increased in the BBN-treated rats, which was prevented in the Atorva + BBN group. No differences were found for CD31 expression. In conclusion, Atorvastatin had a clear inhibitory effect on bladder cancer development, probably due to its antioxidant, anti-proliferative and anti-inflammatory properties.

Complementary markers for the clinical severity classification of hereditary spherocytosis in unsplenectomized patients.

Hereditary spherocytosis (HS) is usually classified as mild, moderate or severe using conventional features, namely, hemoglobin (Hb) concentration, reticulocyte count and bilirubin levels, which do not always contribute to an adequate clinical classification. The aim of our study was to establish the importance of some laboratory routine parameters, as markers of HS clinical outcome, by studying a control group (n=26) and unsplenectomized HS patients (n=82) presenting mild, moderate or severe HS. We performed a basic hematologic study and evaluated the reticulocyte count, bilirubin, erythropoietin (EPO) and soluble transferrin receptor (sTfR) levels; the osmotic fragility (OFT) and criohemolysis tests (CHT); the ratios Hb/MCHC (mean cell hemoglobin concentration), Hb/RDW (red cell distribution width) and MCHC/RDW, were calculated. Hb changed significantly in accordance with HS severity, but not reticulocytes or bilirubin. We found that MCHC, RDW, EPO, sTfR, OFT, CHT and the calculated ratios were significantly changed in patients, and, therefore, were valuable as complementary diagnostic tools for HS. Moreover, RDW, Hb/MCHC, Hb/RDW and MCHC/RDW changed significantly with worsening of HS; thus, they are also good markers for the clinical outcome of HS. In conclusion, we propose the use of these routine parameters as useful to complement the analysis of HS severity.