Antibodies against 5-hydroxymethyl-2'-deoxyuridine are associated with lifestyle factors and GSTM1 genotype: a report from the Malm? Diet and Cancer cohort.

Plasma autoantibodies (aAbs) against the oxidized DNA base derivative 5-hydroxymethyl-2'-deoxyuridine (5-HMdU) are potential biomarkers of cancer risk and oxidative stress. We examined their association with a number of cancer risk factors: smoking, alcohol habits, body fatness, and absence of the glutathione S-transferases M1 and T1 (GSTM1 and GSTT1) in a sample from the population-based Malm? Diet and Cancer cohort (Sweden). This was a cross-sectional study of 264 men and 280 women, 46-67 years of age. Anti-5-HMdU aAb concentration was determined by an ELISA. Data on tobacco exposure were collected through a questionnaire. Alcohol consumption was estimated by a modified diet history method. Body fatness was assessed by a bioimpedance method. The absence or presence of genes coding for GSTM1 and GSTT1 was determined in granulocyte DNA by a multiplex PCR technique. aAb titers were significantly greater in those with high alcohol consumption. Current smokers lacking GSTM1, particularly men, had greater aAb titers compared with nonsmokers or persons expressing GSTM1. Body fatness was inversely associated with antibody titers in men. GSTT1 genotype was not associated with aAb titers. Overall, women had higher aAb titers than men. Adjustment for potential confounders (history of chronic diseases, anti-inflammatory medication, and season of blood sampling) did not change the results. Our study shows that a high alcohol consumption, smoking in combination with lack of GSTM1, and low body fatness (in men) is associated with high titers of anti-5-HMdU aAbs in this population.     

Effect of tissue fixatives on telomere length determination by quantitative PCR

Telomere length is a well established marker of cellular senescence and thus biological age. Quantitative PCR allows the determination even from very low amounts of tissue by using telomere specific and single copy gene primers. Comparing a directly processed tissue sample to a 4% formaldehyde fixed one showed a significantly reduced efficiency of PCR reactions (mainly in single copy gene experiments) in a storage time-dependent manner resulting in an artificial increase in reported relative telomere length. This effect was not seen when the tissue was stored in RNA later solution. In summary, telomere length determination from formaldehyde fixed material by quantitative PCR is not a reliable method. Unfortunately therefore, many easily accessible tissue samples from pathology laboratories are unsuitable for this technique.     

Rheological properties of red blood cells in kidney transplant recipients: the role of lipid profile and type of immunosuppresion

INTRODUCTION: The main rheological properties of red blood cells (RBC) are deformability and aggregability. Deformability is one of the most important factors of RBC flow in high-shear rate areas, especially in the microcirculation. Aggregability of erythrocytes can impair circulation in low-shear rate areas. Both deformability and aggregability of RBC are abnormal in patients with renal insufficiency and after kidney transplantation. Cyclosporine (CsA) and less frequently tacrolimus (Tc) may cause hyperlipidemia and hypertension. Dobiasova et al proposed the term Atherogenic Index of Plasma (AIP), defined as a log (TG/HDL-C). Subjects with high AIP have and higher risk of cardiovascular complications due to atherosclerosis. Hence the aim of this study was to compare aggregability and deformability of RBC from kidney transplant recipients on CsA or Tc-based immunosuppression with healthy volunteers and subjects with dyslipidemia (control groups). Both control and transplant recipient groups were arbitrarily divided by value of AIP as < or = 0 (AIP-) or >0 (AIP+). Deformability and aggregability of erythrocytes were measured using Rheodyn SSD and Myrenne Aggregometer, respectively. RESULTS: We observed a significant increase in aggregation index at stasis in CsA-treated patients and an increased deformability in Tc-treated patients with negative AIP. Deterioration of hemorheological properties of RBC in kidney transplant recipients was confined to an increased aggregability in CsA-treated patients regardless of AIP value. An increased deformability of RBC in Tc-treated patients with normal lipid profiles may suggest a positive effect of Tc on mechanical properties of RBC.     

-174G/C interleukin-6 gene polymorphism and the risk of transplanted kidney failure or graft loss during a 5-year follow-up period

The influence of cytokine gene polymorphisms on transplanted kidney outcome is not well understood. The aim of this one-centre study was to analyse the association between tumour necrosis factor-α (TNF-α), interleukin-6 (IL-6), IL-10, interferon-γ (IFN-γ) and transforming growth factor-β1 (TGF-β1) genotypes and the incidence of delayed graft function (DGF), acute rejection (AR) and 5-year kidney graft loss. Genotyping was performed in 199 subsequent kidney graft recipients from deceased donors without induction therapy based on polymerase chain reaction method using sequence-specific primers for TNF-α (-308A/G), IL-10 (-1082A/G, -819T/C and -592A/C), IL-6 (-174G/C), IFN-γ (+874T/A) and TGF-β1 (in codons 10T/C and 25G/C). Genotypes were grouped according to the strength of cytokine expression. During a 5-year follow-up period, 14 patients died with functioning graft and 33 developed graft failure. The analysed polymorphisms were not associated with the incidence of DGF. The frequency of early episodes of AR was significantly associated only with TGF-β1 genotype. There was an association between -174G/C IL-6 gene polymorphism and the death-censored kidney graft survival. The risk of graft loss during 5-year follow-up period was greater by 57% for GG or GC (higher IL-6 production) than for CC carriers. None of the other analysed polymorphisms significantly influenced both patients and kidney graft survival, also in the analysis of the subgroup with human leucocyte antigen-DR mismatch. -174G/C IL-6 genotype of the kidney graft recipient could modulate the rate of graft excretory function deterioration and the risk of graft loss by influencing their constitutional expression.     

Plasma adiponectin concentration in patients after successful kidney transplantation--a single-center, observational study

BACKGROUND AND AIM: Adiponectin is an anti-inflammatory protein secreted almost exclusively by adipocytes which improves insulin sensitivity and presents antiatherogenic properties. Plasma adiponectin concentration is almost 3 times higher in hemodialysis patients and markedly decreased after successful kidney transplantation. However, until now, there are no studies analyzing plasma adiponectin concentration in kidney transplant patients (KTx) during the long-term period after transplantation. Therefore, the aim of present study was to examine plasma adiponectin concentration in KTx patients during the wide range of time after transplantation. MATERIAL AND METHOD: Single center, cross-sectional study including 228 KTx adult recipients (143 M and 85 F) with estimated glomerular filtration rate (eGFR) > or = 15 ml/min, 80 hemodialysis patients (34 M and 46 F) and 52 healthy subjects (33 M and 19 F). Plasma adiponectin concentration was estimated together with HOMA-IR (homeostasis model assessment insulin resistance index) and plasma lipid profile. RESULTS: In KTx patients plasma adiponectin concentration 14.0 (13.1-15.0) microg/ml was significantly (p < 0.001), lower than in hemodialysis ones 29.0 (24.7-33.3) microg/ml, however, significantly (p < 0.001) higher than in healthy subjects 10.1 (8.8-11.5) microg/ml. Among KTx patients the highest plasma adiponectin concentration was observed in the subgroup of patients surviving with the functioning graft more than 8 years after transplantation. In KTx patients, significant, negative correlations were found between plasma adiponectin concentration and BMI (p = 0.017), HOMA-IR (p = 0.02) and estimated GFR (p < 0.009), respectively. Multiple regression analysis performed in the group of KTx patients, with plasma adiponectin concentration as the dependent variable and BMI, age, gender, estimated GFR as independent variables showed that in this model (R2 = 0.09) plasma adiponectin concentration significantly depends on BMI (p = 0.035), gender (p = 0.004) and eGFR (p = 0.023). CONCLUSIONS: Patients with long-term renal graft survival are characterized by a higher plasma adiponectin concentration. Kidney graft function (assessed as estimated GFR) is an important factor influencing plasma adiponectin concentration.