Hepatocyte Growth Factor in Predialysis and Hemodialysis Chronic Kidney Disease Patients.

Chronic kidney disease (CKD) which is characterized by progressive loss of renal function and renal fibrosis is a worldwide public health problem. Hepatocyte growth factor (HGF) is a polypeptide that exhibits multiple functions including antifibrotic effects on kidneys. The present study was aimed at evaluating HGF levels and studying its association with markers of inflammation and oxidative stress in patients of predialysis and dialysis CKD. A total of 80 subjects including 20 healthy controls, 40 patients of CKD stage 1 to stage 5 (predialysis), and 20 CKD patients with end-stage renal disease on hemodialysis were recruited. HGF, high-sensitivity C-reactive protein (hsCRP), malondialdehyde (MDA), and ferric reducing ability of plasma (FRAP) were measured in all the subjects. HGF levels were significantly higher in all patients with CKD compared to controls. The levels were found to be lower in patients on dialysis than in the predialysis group; however, the difference was not statistically significant. hsCRP, MDA, and FRAP were significantly higher in all patients with CKD than in controls. HGF levels did not show a significant correlation with the markers studied. HGF levels were increased in response to renal injury in CKD patients. The levels were higher in predialysis patients of CKD than in CKD patients on dialysis. HGF levels may be used as an indicator of renal fibrosis in patients with CKD.

Efficacy of oral rosuvastatin intervention on HDL and its associated proteins in men with type 2 diabetes mellitus.

PURPOSE: High-density lipoprotein (HDL) undergoes structural and functional modification in patients with type 2 diabetes mellitus (T2DM). There are limited data on effect of rosuvastatin on HDL-associated proteins and the antiatherogenic effects of rosuvastatin. The present study intended to study the efficacy of rosuvastatin intervention on HDL-associated proteins and its other antiatherogenic effects in men with T2DM. METHODS: Men with T2DM on oral antidiabetic treatment, with LDL-C levels > 75 mg/dL and willing for rosuvastatin intervention (20 mg/day orally for a period of 12 weeks), were included. Fasting glucose, lipid profile were measured using standard methods. Oxidized low-density lipoprotein (oxLDL), oxidized HDL (oxHDL), paraoxonase-1 (PON-1), tumour necrosis factor-α (TNF-α) and lecithin:cholesterol acyltransferase (LCAT) in serum were measured by ELISA; serum myeloperoxidase (MPO) by spectrophotometric method and cholesterol efflux by fluorometric assay. Carotid intima-media thickness (cIMT) measurement to assess vascular health status was done using doppler. RESULTS: Rosuvastatin produced a significant decrease (p < 0.05) in lipids (total cholesterol, triglycerides, LDL-C); oxidative stress (oxLDL, oxHDL, MPO); inflammation (TNF-α); LCAT concentration; cIMT; significant increase in antiatherogenic HDL and cholesterol efflux (p < 0.05) and no change in apoA-I levels from baseline to 12 weeks of follow-up. A decrease in MPO activity was found to be independently associated with an increase in cholesterol efflux. CONCLUSIONS: Post intervention there is a quantitative and qualitative improvement in HDL, which helps in its reverse cholesterol transport (RCT) and antioxidant functions. Improvement in HDL functions and suppression of inflammation by rosuvastatin lead to regression in cIMT, which is beneficial in decreasing the progression of cardiovascular disease (CVD) in men with diabetes.

Correction to: Efficacy of oral rosuvastatin intervention on HDL and its associated proteins in men with type 2 diabetes mellitus.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.

Osteopontin, Cardiovascular Risk Factors and Carotid Intima-Media Thickness in Chronic Kidney Disease.

The pleiotropic cytokine osteopontin (OPN) is found to be involved in the pathogenesis of both kidney and cardiovascular disease (CVD). We evaluated the relationship between OPN, other cardiovascular risk factors and carotid intima-media thickness (CIMT) in chronic kidney disease (CKD) (predialysis) patients. This is a 2-year cross-sectional prospective study involving 75 patients with CKD from stage 1 to stage 5 attending the nephrology outpatient department and 25 healthy controls. Routine biochemical parameters were analyzed on clinical chemistry Autoanalyzer Beckman Coulter DXC 600 Synchron, USA. OPN was estimated by ELISA method. Carotid intima-media wall thickness was estimated by Doppler of carotid vessels. Serum OPN and other nontraditional cardiovascular risk factors such as CIMT, lipoprotein (a) Lp(a), fibrinogen, and homocysteine were significantly increased in patients of CKD compared to controls. OPN, Lp(a), fibrinogen, CIMT, parathyroid hormone, and homocysteine progressively increased from early stages of CKD and increased further with progression of the disease, but nitric oxide (NO) level progressively decreased with progression of CKD. OPN showed a positive correlation with CIMT, Lp(a), fibrinogen, and homocysteine and negative correlation with estimated glomerular filtration rate and NO. There was a close direct association between circulating levels of OPN and the presence of atherosclerotic plaques in carotid arteries of patients with CKD. Osteopontin and nontraditional CVD risk factors are altered in early stages of CKD and might predict adverse outcomes in these patients.

Carbamylated Hemoglobin can Differentiate Acute Kidney Injury from Chronic Kidney Disease.

Carbamylated hemoglobin (CarHb) was found to have a potential role in the differentiation of patients with acute kidney injury (AKI) from chronic kidney disease (CKD). This study was aimed at the evaluation of the diagnostic performance and usefulness of CarHb in the differentiation of AKI from CKD. Forty patients with renal disease and twenty age- and sex-matched healthy controls were included in the study. Urea, creatinine, Hb, and CarHb were measured in all the subjects. Patients with AKI and CKD were found to have significantly increased levels of CarHb when compared to controls (P < 0.05 for both groups). Patients with CKD had significantly increased levels of CarHb when compared to patients with AKI (P < 0.05). CarHb showed significant positive correlation with urea in patients with renal disease (r = 0.776, P < 0.0001). Significant area under curve (AUC = 0.840, P < 0.0001) was obtained for CarHb and a cut-off value of 98.33 µg VH/g Hb resulted with the best combination of 85% sensitivity and 75% specificity. CarHb may provide clinical utility since patients with AKI and CKD have similar clinical presentation usually. A cut-off value of 98.33 µg VH/g Hb has been found to be useful to differentiate AKI from CKDs.

Simultaneous determination of arginine, citrulline, and asymmetric dimethylarginine in plasma by reverse-phase high-performance liquid chromatography.

BACKGROUND: Arginine, citrulline and asymmetric dimethylarginine (ADMA) are three molecules in the nitric oxide (NO) pathway which provide useful information about vascular endothelial function. ADMA accumulates with patients with chronic kidney disease (CKD) and inhibits NO synthesis. We describe the modification of a previously established method for the measurement of amino acids analysis for simultaneous detection of arginine, citrulline, and ADMA in plasma and to validate its performance in patients with CKD. MATERIALS AND METHODS: Arginine, citrulline, and ADMA were simultaneously separated by reverse-phase high-performance liquid chromatography by precolumn derivatization with O-phthalaldehyde using the modified method. It was then applied for analysis in thirty patients with CKD and thirty healthy controls so as to cover the entire measuring range, i.e., normal and uremic range. RESULTS: The method showed a good performance in terms of linearity, precision, and recovery. The detection limit of the assay for ADMA was found to be 0.05 µmol/L at a signal-to-noise ratio of 3:1. The average within run coefficient of variation for ADMA using this method was 4.7% in the normal range and 1.9% in the uremic range, while the average between-day precision in the normal and uremic range was 6.5% and 5.2%, respectively. Patients with CKD were found to have higher concentration of ADMA compared to controls. CONCLUSION: This method can be useful in assessing the baseline cardiovascular risk in an individual as well as in the follow-up of the patients who are receiving L-arginine, and thus, assess the response to treatment by simultaneous measurement of arginine and ADMA.

Role of Gut-derived Uremic Toxins on Oxidative Stress and Inflammation in Patients with Chronic Kidney Disease.

Several cardiovascular disease (CVD) risk factors have been identified among patients with chronic kidney disease (CKD). Gut-derived uremic toxins (GDUT) are important modifiable contributors in this respect. There are very few Indian studies on GDUT changes in CKD. One hundred and twenty patients older than 18 years diagnosed with CKD were enrolled along with forty healthy subjects. The patients were classified into three groups of forty patients based on stage of CKD. Indoxyl sulfate (IS), para cresyl sulfate (p-CS), indole acetic acid (IAA), and phenol were estimated along with the assessment of oxidative stress (OS), inflammatory state, and bone mineral disturbance. All the GDUT increased across the three groups of CKD. All patients had higher levels of malondialdehyde (MDA), ferric reducing ability of plasma (FRAP), high-sensitivity C-reactive protein (hsCRP), and interleukin-6 (IL-6) as compared to controls. IS and IAA showed positive association with MDA/FRAP corrected for uric acid, whereas IS and p-CS showed positive association with IL-6. IS, IAA, and phenol showed a positive association with calcium × phosphorus product. GDUT increase OS and inflammatory state in CKD and may contribute to CVD risk.

Utility of saliva as a sample to assess renal function and estimated glomerular filtration rate.

Diagnosis of renal diseases by assessing renal parameters in saliva. Biochemical investigations using serum form important component of monitoring patients with renal disease. Utility of saliva, in diagnosis and monitoring of patients with renal disease and for calculation of estimated glomerular filtration rate (eGFR), was studied. Sixty patients with renal disease and sixty ageand sex-matched healthy controls were studied. Urea, creatinine, sodium, potassium, uric acid, calcium, and phosphorus were measured in both serum and saliva. eGFR was calculated using salivary creatinine. Data were expressed as mean ± standard deviation. Comparison and correlation between groups were assessed by Student's t-test and Pearson correlation, respectively. Bland-Altman plot, mountain plot, and intra-class correlation coefficient were used to test agreement. A P <0.05 was considered statistically significant. Statistical analysis was done using Microsoft excel spreadsheets, Medcalc Version 10.0, and SPSS version 11.5. Salivary levels of urea, creatinine, uric acid, sodium, potassium, and phosphorus were higher in patients compared to controls. Potassium and phosphorus levels were higher (P = 0.001) and creatinine, sodium, calcium, and uric acid levels were lower (P = 0.001) in saliva compared to serum in both patients and controls. Positive correlation was observed between serum and salivary urea and creatinine (P < 0.0001). eGFR values calculated from salivary creatinine showed good agreement with those calculated form serum creatinine. Salivary urea (>6 mmol/L) and creatinine (>14.6 µmol/L) and eGFR calculated from salivary creatinine can be used to identify patients with renal disease.

Nitric oxide status in patients with chronic kidney disease.

Patients with chronic kidney disease (CKD) are at an increased risk of cardiovascular (CVD) morbidity and mortality, mainly due to atherosclerosis. Decreased production or reduced bioavailability of nitric oxide (NO) can result in endothelial dysfunction (ED). Multiple mechanisms are known to cause a state of NO deficiency in patients with CKD. Patients in various stages of CKD grouped as group-1 (CKD stage 1 and 2), group-2 (CKD stage 3 and 4), group-3 (CKD stage 5) and healthy controls were included in the study. Each group of patients and controls comprised 25 subjects. Plasma nitrites, L-arginine, asymmetric dimethyl arginine (ADMA) and citrulline were measured in all the subjects. Patients in all stages of CKD had lower NO and higher ADMA levels compared to controls. Further, group-2 and group-3 patients had lower levels of NO and higher levels of ADMA than group-1 patients. L-arginine levels showed no difference between patients and controls. However, group-3 patients had lower L-arginine levels compared to group-1 patients. Citrulline levels were decreased in group-3 patients. NO production was decreased in patients in all stages of CKD. The decrease could be due to decreased availability of the substrate, L-arginine or due to an increased ADMA, a potent inhibitor of endothelial NO synthase. Therapeutic interventions directed towards improvement of NO production in addition to management of other CVD risk factors may prevent development of ED and facilitate proper management of CKD patients who are at increased risk for CVD.

Subclinical atherosclerosis in patients with rheumatoid arthritis by utilizing carotid intima-media thickness as a surrogate marker.

BACKGROUND & OBJECTIVES: Patients with rheumatoid arthritis (RA) are more prone for accelerated atherosclerosis and Asian Indians as an ethnic group are predisposed to a high risk of premature atherosclerosis. However, sparse data are available regarding the burden of atherosclerosis among asymptomatic adult patients with RA in south India. We studied the burden of asymptomatic atherosclerosis in adult south Indian patients with RA at Tirupati, Andhra Pradesh, India, utilizing carotid intima-media thickness (CIMT) as a surrogate marker. METHODS: Ultrasound examination of the carotids and CIMT measurement (mm) were carried out in 32 patients with RA, 32 age- and gender-matched normal controls, and 32 patients with atherosclerosis and angiographically proven coronary artery disease. The CIMT values in patients with CAD and normal controls were used to derive the appropriate cut-off value of CIMT for defining atherosclerosis that would be applicable for the ethnic population studied. RESULTS: Patients with RA had a higher mean CIMT (mm) compared with normal control subjects (0.598 ± 0.131 vs 0.501 ± 0.081; p0 = 0.001). Carotid plaque was found more frequently among the cases compared with normal controls [5/32 (15.6%) vs 0/32 (0%), p0 =0.020]. Using this cut-off value derived by the receiver operator characteristic curve method (≥ 0.57 mm; sensitivity 84.4; specificity 90.6%) and the 75 th percentile value among normal controls (≥ 0.55 mm) as surrogate markers, the presence of subclinical atherosclerosis was significantly more among asymptomatic patients with RA compared with normal controls [(59.3 vs 12.5%; p0 <0.001) and (62.5 vs 25%; P<0.001) respectively]. INTERPRETATION & CONCLUSIONS: Based on the present findings CIMT appears to be a useful surrogate marker for detecting subclinical atherosclerosis in adult Indian patients with RA.

Evaluation of protein oxidation and its association with lipid peroxidation and thyrotropin levels in overt and subclinical hypothyroidism.

Both overt (OHT) and subclinical hypothyroid (SHT) disorders have been found to be associated with increased oxidative stress (OXS). Excess thyrotropin [thyroid stimulating hormone (TSH)] is known to directly produce OXS. Increased lipid peroxidation is known to facilitate protein carbonylation. However, the associations between lipid and protein oxidation and elevated TSH levels have not been studied. Thyroid profile, lipid peroxidation as malondialdehyde (MDA) levels and protein carbonylation as protein carbonyls (PCO) were estimated in OHT and SHT groups consisting of 36 patients each, in comparison to 39 euthyroid controls. We also determined the associations between TSH, MDA, and PCO levels in OHT and SHT groups. Increased oxidative damage was evidenced through significant elevations in the concentrations of MDA and PCO in OHT and SHT groups compared to controls (p < 0.01). Both TSH and MDA levels were positively associated with PCO in OHT group. Partial correlation analysis revealed that both excess TSH and increased MDA levels are mutually influencing elevated PCO. The results indicate that there is a simultaneous oxidative damage to lipids and proteins leading to increased MDA and PCO levels in both patient groups. Either of the excess TSH and increased MDA levels are combinably involved in the elevation of PCO in hypothyroidism.

Acute renal failure in falciparum malaria: clinical characteristics, demonstration of oxidative stress, and prognostication.

In this prospective study, we aimed to assess the clinical characteristics of acute renal failure (ARF), determine oxidative stress, as well as to predict the outcome in patients with severe falciparum malaria (FM). The study included a total of 75 subjects; there were 25 adult patients with acute severe FM and ARF, 25 adult patients with uncomplicated FM without ARF, and 25 age- and sex-matched healthy subjects who served as controls. In patients with severe FM and ARF (n = 25), renal failure was non-oliguric in 28% and oliguric in 72%. The average duration of renal failure was 10.53 ± 4.0 days. Sixty percent recovered and 40% died. All patients with non-oliguric presentation recovered. The mean serum malondialdehyde (MDA) levels were 0.82 ± 0.43 µmol/L, 2.97 ± 1.11 µmol/L, and 6.86 ± 2.62 µmol/L, respectively, in healthy controls, in patients with uncomplicated FM, and in those with severe FM with ARF. The Acute Physiology Age and Chronic Health Evaluation II (APACHE II) score, Sequential Organ Failure Assessment (SOFA) score, and the Acute Tubular Necrosis-Individual Severity Index (ATN-ISI) score were all significantly higher in the expired group (19 ± 5.49) when compared to the survivor group (14.4 ± 3.15) (P = 0.014). Kaplan-Meier survival analysis showed that survival was low in patients with delayed hospitalization and longer duration of symptoms. Also, we observed a high occurrence of acute respiratory distress syndrome and central nervous system involvement among the patients who expired.

The effect of L-carnitine supplementation on lipid parameters, inflammatory and nutritional markers in maintenance hemodialysis patients.

Protein energy malnutrition and inflammation are common and usually concurrent in maintenance hemodialysis (MHD) patients. Carnitine, a small molecule involved in fatty acid metabolism, is significantly decreased in long-term HD patients. L-Carnitine supplementation may have potential benefits in improving dialysis-related disorders. However, there are conflicting reports with regard to the beneficial effects of L-Carnitine supplementation. Hence, the present study was carried out to evaluate the effect of L-Carnitine supplementation on lipid parameters, apoproteins and inflammatory and nutritional markers in HD patients. A total of 35 patients with end-stage renal disease, on MHD for a period of 2 to 5 years were recruited into the study. The study group consisted of 20 patients who received Carnitine supplementation intravenously three times a week after each HD session, at 1 g/dose, while the control group consisted of 15 patients without supplementation with L-Carnitine. Highly sensitive C-reactive protein (hsCRP), total protein, albumin, lipid profile and apoprotein AI and B were determined at baseline and at the end of the study. A significant decrease in the hsCRP levels was observed in the Carnitine-supplemented group (P < 0.05). However, no significant change was observed in the lipid parameters and nutritional markers in the Carnitine-supplemented group. In conclusion, the present study demonstrates the significant benefit of L-Carnitine supplementation on inflammatory status in MHD patients as noted by marked decrease in hsCRP levels in comparison with the control group.

Oxidative stress in hemodialysis--postdialytic changes.

BACKGROUND: There is evidence for production of free oxygen radicals during hemodialysis. Hemodialysis is an intervention that is intermittent and is usually undertaken once in two or three days. It is known that the free oxygen radicals are short lived. Hence, it is necessary to know how long the effects of this oxidative stress are seen in the postdialytic period and whether they are carried over to the next dialysis. Review of the literature showed that there is no information in this area. Hence, this study was undertaken in order to learn whether oxidative stress due to a dialysis session is carried over to next dialysis session or not. METHODS: The effects were studied after four different types of membrane and dialysate--Polysulphone-Bicarbonate (PB), Polysulphone-Acetate (PA), Cuprophan-Acetate (CA) and Cuprophan-Bicarbonate (CB). Two consecutive dialysis sessions were studied to know the effect of re-use of the membrane. For each dialysis session, blood samples were collected at 0 (immediately prior to dialysis or preHD), 4 (immediate postdialysis), 6, 12, 24 and 48 hours (start of next session). Lipid peroxides, SOD and GP were determined in erythrocytes. Vitamins A and E and lipid peroxides were estimated in plasma. RESULTS: In the postdialytic phase there was an increase in plasma lipid peroxide levels. Plasma vitamin E levels increased significantly in all groups after first use dialysis, whereas the increase found after re-use dialysis was not statistically significant. Erythrocyte lipid peroxide levels showed a significant decrease. No significant changes were observed in the plasma vitamin A, erythrocyte SOD and GP levels. There was no significant change in any of the parameters between preHD and either 48-hour or 96-hour samples in all groups studied. CONCLUSIONS: Our results show that there is no carry-over of oxidative stress produced by dialysis to the next session regardless of the type of dialysis.