This research has been set up to study the possibility of lipid peroxidation and lipid profile variation in haemodialysis patients. Twenty two patients with Chronic Renal Failure (CRF) disease who werehaemodialyzed at 5th Azar hospital of Gorgan Dialysis Center were recruited for this study (2005). The patients dont have coronary heart disease. 22 age and sex matched healthy control were recruited for this study. Plasma levels of lipid peroxidation and lipid profile were determined in haemodialysis patients and compare with control groups. The results from this research projects indicate that Plasma levels of lipid peroxidation (1.27±0.23 nmol mL-1) and triglyceride (195.22±20.28 mg dL-1) in haemodialysis patients were significantly increased when compared with control subjects (0.98±0.17 nmol mL-1, 151.09±5.74 mg dL-1, respectively), whereas plasma level of total cholesterol (171.68±16.30 mg dL-1), High Density Lipoprotein cholesterol (HDL-C, 44.13±5.38 mg dL-1) in haemodialyzed patients showed no significant difference when compared with control subjects (170.77±14.73 and 44.77±5.29 mg dL-1, respectively). The changes in level of plasma lipid peroxidation and triglyceride in haemodialyzed patients, maybe related with the patient uremia, dialysis membrane and the dialysis process. The metabolic alterations accompanying renal failure may be responsible for dyslipidemia independent of the fat distribution in haemodialysis patients. These states of affairs may play an important role in progress of cardiovascular abnormality in haemodialyzed patients. Due to this conditions a review of haemodialysis membrane, the techniques used in the dialysis, the consumption of various oral antioxidant, the elimination of active oxygen from the dialysis surrounding are among the measures which can prevent sudden cardiovascular abnormality in the haemodialysis patients.
PDF Abstract XML References Citation
How to cite this article
Heart disease is a major cause of morbidity and mortality among patients with renal failure. Mortality in dialysis patients is dramatically higher than in the general population and cardiovascular disease is the leading cause of mortality among these patients (Foley et al., 1998). Chronic renal failure is often associated with dyslipidemia. Lipid profile abnormalities has been identified as an independent risk factor for atherosclerosis (Green et al., 1983; Jeppesen et al., 1998; Assman and Schulte, 1992; Hokanson and Austin, 1996). Some of them persisting and becoming worse during dialysis treatment.
Patients with chronic renal failure, including those receiving regular long-term haemodialysis have a high incidence of premature cardiovascular disease (Loughrey et al., 1994). Free radicals may cause lipid peroxidation (the level of lipid peroxidation expressed as malondialdehyde) and damage macromolcules and cellular structure of the organism, endothelium and erythrocytes. Plasma malondialdehyde (MDA) is the breakdown product of the major chain reactions leading to definite oxidation of polyunsaturated fatty acids such as linoleic and linolenic acid and thus serves as a reliable marker of lipid peroxidation (Boaz et al., 1999a; Fiorillo et al., 1998). Plasma MDA is a predictor of cardiovascular disease in patients on haemodialysis, which may underscore the role of oxidative stress as a cardiac risk factor in these patients (Boaz et al., 1999b). Some studies have shown that haemodialysis is connected with increased free radical production (Bast et al., 1991). Clinical and subclinical myocardial ischaemia are common among chronic renal failure patients, both before and during dialysis (Foley et al., 1995; Singh et al., 1994). The prevalence of ischaemic heart disease in haemodialysis patients in 10-20 times higher than that in the general population with 50% mortality due to Cardiovascular disease. According to the US Renal Data System 42% of patients undergoing haemodialysis have had a myocardial infarction or Coronary revasculariztion. In addition, the rate of survival after myocardial infarction is much lower for haemodialysis patients than for the general population (Heeschen et al., 2000).
Dyslipidemia and oxidative stress may be the main atherogenic risk factors in chronic renal failure (Chan et al., 1981).
For this reason the aim of this study with the discriminative information was to evaluate the effect of haemodialysis on plasma lipid peroxidation (the level of lipid peroxidation expressed as malondialdehyde) and lipid profile (total cholesterol, High Density Lipoprotein cholesterol (HDL-C) and triglyceride in haemodialysis patients and compare with control groups.
MATERIALS AND METHODS
The sampling procedure was purposive sampling which carried out on 22 haemodialysis patients (without symptoms of myocardial ischaemia) with average age 43.54±9.21 years of old (range 21-55). The mean length of dialysis for each patients was 3.95±0.14 h with average 2.27±0.45 times a week. Neither of them received antioxidant medicines and foods. Patients were chosen (14 male, 8 female) from the patients reffered to the Department of Haemodialysis Center at 5th azar hospital in Gorgan University of Medical Sciences (2005). The patients studied had no evidence of vascular complications, including hypertension, coronary artery disease. Blood samples were obtained from the patients during fasting in a heparinized tubes. Plasma is seperated as soon as the blood taken.The plasma total cholesterol, High Density Lipoprotein cholesterol (HDL-C) and triglyceride (TG) were determined for haemodialyzed patients, using routine laboratory kit specterophotometry technique (model JENWAY 6105 UV/VIS) in the Laboratory of Biochemistry (Faculty of Medicine). The plasma lipid peroxidation (the level of lipid peroxidation expressed as malondialdehyde (MDA) was determined with Kei Satoh (1978) method. Data was analyzed by students t-test using spss-11.5 software. p-value less than 0.05 was considered significant.
To 0.5 mL plasma, 2.5 mL of trichloroacetic acid is added and the tube is left to stand for 10 min at room temperature. After centrifugation at 3500 rev. min for 10 min, the supernatant is decanted and the precipitate is washed once with sulfuric acid. Then 2.5 mL sulfuric acid and 3 mL thiobarbituric acid (TBA) in sodium sulfate are added to this precipitate and the coupling of lipid peroxide with TBA is carried out by heating in a boiling water bath for 30 min. After cooling in a cold water, the resulting chromogen is extracted with 4 mL of n-butyl alcohol by vigorous shaking. Separation of the organic phase is facilitated by centrifugation at 3000 rev./min for 10 min and its absorbance is determined at the wavelength of 530 nm.
RESULTS AND DISCUSSION
Plasma levels of malondialdehyde and lipid profile of 22 haemodialyzed patients and control subjects are reported in Table 1. There are a tendency to higher triglyceride and malondialdehyde levels in haemodialyzed patients when compared to control subjects. The difference is statistically significant. It was no significant difference of total cholesterol and HDL cholesterol between haemodialyzed patients and control subjects.
Several treatment approaches are currently proposed or are under investigation in order to decrease the burden of cardiovascular disease in the haemodialysis patients. Cardiac mortality is the greatest contributor to overall mortality in this susceptible population,vigorous efforts are required to identify and correct potential factors that may exacerbate this problem.The aim of the present study was to determine and compare the plasma levels of malondialdehyde and lipid profile (total cholesterol, High Density Lipoprotein Cholesterol (HDL-C) and triglyceride (TG) in predicting the outcome of haemodialysis patients on regular dialysis.
There are a few reports describing difference in plasma lipid peroxidation and lipid profile in haemodialyzed patients. Some of the studies showed an increase while some other showed a decrease or no significant differences. This study has demonstrated that plasma levels of malondialdehyde and triglyceride were significantly higher in the haemodialysis patients than in the control subjects, while the plasma levels of total cholesterol and High Density Lipoprotein Cholesterol (HDL-C) showerd no significant differences in both groups. Canestrari et al. (1995) reported that the level of plasma malondialdehyde in haemodialyzed patients was higher than healthy controls.Study of Samouilidou et al. (2003) on 31 haemodialysis patients and 17 control group showed that plasma malondialdehyde of haemodialysis patients decreased when compared with control groups. Some researchers (Loughrey et al., 1994; Canestrari et al., 1995; Ozden et al., 2002; Taylor et al., 1992; Toborek et al., 1992; Balashova et al., 1992) reported that the level of plasma malondialdehyde in haemodialysis patients increased when compared with control groups. The present show a significant increase of plasma malondialdehyde in haemodialysis patients when compared with control groups. Present results are in agreement with the groups mentioned in that the plasma level of malondialdehyde of haemodialysis patients is significantly increased from that of controls (Loughrey et al., 1994; Canestrari et al., 1995; Ozden et al., 2002, 1992; Toborek et al., 1992; Balashova et al., 1992). But the results of this study are not in agreement with the results of Samouilidou et al. (2003) showing plasma of malondialdehyde of haemodialysis patients were significantly decreased. This situation probably in due to direct relation between the blood of haemodialtsis patients with dialysis instrument, which is an conductive factor in oxidative stress and subsequent increased production of free radicals in haemodialysis patients. The probable Oxidative destruction can be due to increasing production of free radicals (Hussain et al., 1995; Dasgupta et al., 1992; Sanaka et al., 1995). An oxidative stress due to overproduction of reactive oxygen spcies by activated monocytes and impairment in antioxidant defence mechanisms (Loughrey et al., 1994; Paul et al., 1993; Saint-Georges et al., 1989) may be take place in haemodialysis patients (Cristol et al., 1994; Himmelfarl et al., 1991) and may contribute to the accelerated haemodialysis-induced atherogenesis by oxidatively modified proteins and lipids. There are a few studies describing difference in plasma lipid peroxidation and lipid profile in haemodialyzed patients without myocardial ischaemia symptoms.
|Table 1:||The plasma levels of total cholesterol, Triglyceride, HDL cholesterol and Malondialdehyde in haemodialysis patients and control groups|
The diagnosis of myocardial ischaemia is difficult in haemodialysis patients since they are not able to perform adequate exercise tests due to limited exercise tolerance.
Lee et al. (1997) suggested that the uraemic condition affected lipid abnormality. Odamaki et al (1999) showed that the presence of renal failure would modify lipid metabolism by altering the fat distribution. Prichard et al. (2003) showed that plasma levels of triglyceride and malondialdehyde in patients who undergo haemodialysis are increased while HDL-cholesterol are decreased.
Sharma et al. (1980) reported that hypertriglyceridemia was observed in only 2 out of 19 cases on dialysis. Ibels et al. (1976) also reported decrease in hypertriglyceridemia after initiation of dialysis. This may be due to improved triglyceride removal by increased post heparin lipolytic activity and decreased peripheral resistance to insulin after initiation of dialysis. Moberly et al. (2002) showed that plasma level of total cholesterol and triglyceride increased in haemodialysis patients when compared with control groups, while HDL-cholesterol decreased in these patients. Peresent results are in agreement with the groups mentioned in that the plasma level of triglyceride of haemodialysis patients is significantly increased from that of controls (Prichard, 2003; Moberly et al., 2002). But the results of this study are not in agreement with the results of some researchers showing plasma of triglyceride of haemodialysis patients were significantly decreased (Ibels et al., 1976) or not changed (Sharma et al., 1980). The results of this study also are not in agreement with the groups showing plasma of HDL-cholesterol of haemodialysis patients were significantly increased (Prichard, 2003) and decreased (Moberly et al., 2002).
The observation of meaningful increasing level of plasma lipid peroxidation and triglyceride in the haemodialyzed patients, maybe related with the patient uraemia, dialysis membrane and the dialysis process (may increase lipid peroxidation during the dialysis process). The metabolic alterations accompanying renal failure may be responsible for dyslipidemia independent of the fat distribution in haemodialysis patients. Haemodialysis patients have been reported to have a decreased concenteration of hepatic lipase (Arnadottir et al., 1995) and an increased level of the lipoprotein lipase inhibitor (Moberly et al., 1999). These states of affairs may play an important role in progress of cardiovascular abnormality in haemodialyzed pateints. Due to this conditions a review of haemodialysis membrane, the techniques used in the dialysis, the consumption of various oral antioxidant, the elimination of active oxygens from the dialysis surrounding are among the measures which can prevent sudden cardiovascular abnormality in the haemodialysis pateints and ultimately these important factors up-grade the pateints quality of life and prevent sudden silent myocardial infarction.
This research was supported by research deputy of Golestan University of Medical Sciences.I acknowledge with thanks the help of Research and Biochemistry Departments.
- Arnadottir, M., H. Thysell, J. Dallongeville, J.C. Fruchart and P. Nilsson-Ehle, 1995. Evidence that reduced lipoprotein lipase activity is not a primary pathogenic factor for hypertriglyceridemia in renal failure. Kidney Int., 48: 779-784.
- Assman, G. and H. Schulte, 1992. Relation of high density lipoprotein cholesterols and triglycerides to incidence of atherosclerotic coronary artery disease (the PROCAM experience). Prospective cardiovascular munster study. Am. J. Cardiol., 70: 733-737.
- Balashova, T.S., J.A. Rud'ko, V.M. Ermolenko, P. Tsalenchuk and A.A. Kubatiev, 1992. Lipid peroxidation as a possible mechanism of erythrocyte damage in patients with chronic kidney failure on hemodialysis. Ter. Arkh., 64: 66-69.
- Cristol, J.P., B. Canaud, H. Rabesandratana, I. Gaillard, A. Serre and C. Mion, 1994. Enhancement of reactive oxygen species production and cell surface markers expression during hemodialysis. Nephrol. Dial. Transplant., 9: 389-394.
- Foley, R.N., P.S. Parfrey, J.D. Harnett, G.M. Kent, C.J Martin, D.C Murray and P.E. Barre, 1995. Clinical and echocardiographic disease in patients starting end-stage renal disease therapy. Kidney Int., 47: 186-192.
- Heeschen, C., A. Deu, L. Langenbrink, B. Goldmann and C. Hamm, 2000. Analytical and diagnostic performance of troponin assays in patients suspicious for acute coronary syndromes. Clin. Biochem., 33: 359-368.
- Himmelfarl, J., M. Lazarus and R. Hakim, 1991. Reactive oxygen species production by monocytes and polymorphonuclear leukocytes during dialysis. Am. J. Kidney Dis., 17: 271-276.
- Hokanson, J.E. and M.A. Austin, 1996. Plasma triglyceride level is a risck factor for cardiovascular disease independent of high density lipoprotein cholesterol level: A meta-analysis of population-based prospective studies. J. Cardiovasc. Risk, 3: 213-219.
- Lee, P.O., D. Neal, B. Murphy and J. Best, 1997. The role of abdominal adiposity and insulin resistance in dyslipidemia of chronic renal failure. Am. J. Kidney Dis., 29: 54-65.
- Loughrey, C.M., I.S. Young, J.H. Lightbody, D. McMaster, P.T. McNamee and E.R. Trimble, 1994. Oxidative stress in haemodialysis. Q. J. Med., 87: 679-683.
- Moberly, J.B., P.O. Attman, O. Samuelsson, A.C. Johansson, C. Knight-Gibson and P. Alaupovic, 1999. Apolipoprotein C-III, hypertriglyceridemia and triglyceride rich lipoproteins in uremia. Electrolyte Metab., 25: 258-262.
- Moberly, J.B., P.O. Attman, O. Samuelsson, A.C. Johansson, C. Knight-Gibson and P. Alaupovic, 2002. Alterations in lipoprotein composition in peritoneal dialysis patients. Peritoneal Dialysis Int., 22: 220-228.
- Odamaki, M., R. Furuya, S. Ohkawa, T. Yoneyama, M. Nishikino, A. Hishida and H. Kumagai, 1999. Altered abdominal fat distribution and its association with the serum lipid profile in non-diabetic hemodialysis patients. Nephrol. Dial. Transplant., 14: 2427-2432.
- Paul, J.L., N.D. Sall, Soni, J.L. Poignet and A. Lindenbaum et al., 1993. Lipid peroxidation abnormalities in hemodialysed patients. Nephron, 64: 106-109.
- Prichard, S., 2003. Impact of dyslipidemia in end-stage renal disease. J. Am. Soc. Nephrol., 14: S315-S320.
- Samouilidou, E. and E. Grapsa, 2003. Effect of dialysis on plasma total antioxidant capacity and lipid peroxidation products in patients with end-stage renal failure. Blood Purif., 21: 209-212.
- Sanaka, T., C. Higuchi, T. Shinobe, H. Nishimura and M. Omata et al., 1995. Lipid peroxidation as an indicator of biocompatibility in haemodialysis. Nephrol. Dial. Transplant., 10: 34-38.
- Singh, N., A. Langer, M.R. Freeman and M.B. Goldstein, 1994. Myocardial alterationsduring hemodialysis: Insight from new noninvasive technology. Am. J. Nephrol., 14: 173-181.