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  • The Internet Journal of Endocrinology
  • Volume 2
  • Number 1

Original Article

Plasma Lipid Peroxidation Zinc And Erythrocyte Cu-Zn Superoxide Dismutase Enzyme Activity In Patients With Type 2 Diabetes Mellitus In Gorgan City (South East Of The Caspian Sea)

A Marjani

Citation

A Marjani. Plasma Lipid Peroxidation Zinc And Erythrocyte Cu-Zn Superoxide Dismutase Enzyme Activity In Patients With Type 2 Diabetes Mellitus In Gorgan City (South East Of The Caspian Sea). The Internet Journal of Endocrinology. 2004 Volume 2 Number 1.

Abstract

Diabetes mellitus is a chronic metabolic disorder, which may be associated with the imbalance between protective effect of antioxidants and increased free radical production. Diabetes mellitus can alter the nutritional status of the individual. The aim of this study was to determine the changes of plasma lipid peroxidation , zinc and erythrocyte cu-zn superoxide dismutase activity in patients with type 2 diabetes mellitus and healthy control in Gorgan city.


Fifty type 2 patients with diabetes mellitus and 50 people without diabetes were included in this randomized study. None of patients studied had any diabetic complications.


The levels of plasma malondialdehyde and zinc from type 2 diabetes mellitus patients (6.24 ± 0.85 nmol / ml and 116.78± 5.51 mg / dl) and control groups (3.63 ± 0.97 nmol / ml and 146.86 ± 9.06 mg / dl) were determined. Erythrocyte Cu-Zn superoxide dismutase activity from patients with diabetes ( 675.34± 60.89 U / g Hb) and control groups (1052.70± 52.76 U / g Hb) were determined.


The increased plasma lipid peroxidation and decreased plasma zinc and erythrocyte Cu-Zn superoxide dismutase activity that we observed in patients with type 2 diabetes mellitus may predispose to the development of cardiovascular complications.We propose that diabetic patients may have elevated requirement for antioxidants. Supplementation with zinc and vitamin or dietary free radical scavengers such as vitamins E and C or tomato, orange and etc. have a potential role in boosting antioxidant-related defences and maybe important in patients with diabetes.

 

Introduction

Free radicals are highly reactive molecules generated by biochemical redox reactions that occur as a part of normal cell metabolism (1). These unstable species may cause oxidative damage to DNA, carbohydrate, proteins and lipids that are normally counteracted by protective antioxidants. Oxidative defense is provided by a number of enzymes and vitamins, including the vitamin E, vitamin C and glutathione (2,3,4). In times of increased free radical production, individuals may become deficient in these antioxidants. Excessive free radical production or low antioxidant level leads to oxidation of cellular lipids, proteins and nucleic acids, which results in fragmentation and cross-linking. This may ultimately lead to cell death with widespread pathological consequences (5) The imbalance between protective antioxidants (antioxidant defense) and increased free radical production, leading to oxidative damage, is known as oxidative stress. Oxidative stress is caused by a relative overload of oxidants, i.e., reactive oxygen species. This impairs cellular functions and contributes to the pathophysiology of many diseases. Evidence has accumulated suggesting that complications of diabetes seem to be partially mediated by oxidative stress (6,7,8).

The function of zinc in the body metabolism is based on its enzymatic affinity, such as a zinc-enzyme complex or Zinc metalloenzyme. In humans and animals, diabetes maybe results in disturbance of these vital trace elements (9). In most mammals, insulin is stored as zinc crystals and is likely secreted in zinc form. Zinc has important role in modulating the immune system, and its dysfunction in diabetes mellitus may be related in part to the status of zinc (10). Lack or inadequate supply of such nutrients produces functional impairment and can result in disease. The clinical significance and evaluation of zinc in regard to different diseases, including diabetes mellitus remains conflicting as well as controversial. Many questions still remain unanswered. Several reports underscore the role of micronutrient status in patients with type 1 or 2 diabetes mellitus (11,12,13,14,15,16,17). Zinc maybe act in normalizing glycemia, and a restored zinc status in patients with type 2 diabetes mellitus may counteract the deleterious effects of oxidative stress, helping to prevent many complications associated with diabetes.

Diabetes mellitus is a major source of morbidity in developed countries. Morbidity and mortality are increased in patients with type 2 diabetes mellitus compared with the general population, particularly with respect to coronary artery disease. One possible explanation for this is that oxidative stress may be a contributory factor. There are contradictory reports on changes in plasma lipid peroxidation , zinc and erythrocyte Cu-Zn superoxide dismutase activity in patients with type 2 diabetes. Some of the studies show an increase whereas others show a decrease, or no significant differences. There are a few reports describing differences in plasma lipid peroxidation, zinc and erythrocyte antioxidant enzymes between patients with type 2 diabetes and controls.

For this reason the present study was designed to determine the changes of plasma lipid peroxidation, zinc and erythrocyte Cu-Zn superoxide dismutase activity in patients with type 2 diabetes mellitus (at a diabetes center in Gorgan city) in comparison to controls.

Material and Methods

Samples were obtained, in a randomized fashion, from 50 patients with type 2 diabetes as well as 50 control subjects. Patients were chosen from the patients referred to the Department of Diabetes Center at the 5 th Azar Hospital in Gorgan University of Medical Sciences. The patients studied had no evidence of vascular complications, including hypertension, coronary artery disease. Controls were defined as not having a major medical illness, no hospital admissions, no current medication, and a subjective perception of good health as determined by health questionnaire. None of the study subjects received any medication and trace element supplement in the previous 2-3 months. Characteristics of both groups are shown in the table 1. Blood samples were obtained after an overnight fast in heparinized tubes. Plasma was separated soon after blood was taken. The plasma malondialdehyde (the level of lipid peroxidation expressed as malondialdehyde [MDA]), fasting blood sugar (FBS) and erythrocyte Cu-Zn superoxide dismutase (SOD), glycated haemoglobin (HbA1c) and hemoglobin (Hb) were determined using laboratory kits and spectrophotometry techniques (model JENWAY 6105 UV / VIS ). Plasma Zi nc(Zn) was analyzed using an atomic absorption spectrophotometry method (Model AA670, Shimadzu, Japan) in the laboratory of biochemistry (Faculty of Medicine). Plasma MDA, FBS and erythrocyte Cu-Zn SOD, HbA1c and Hb were determined using previously described methods (18,19,20,21,22). Data was analyzed by Student's t-test, using SPSS-10 software. P-value < 0.05 was considered significant.

Figure 1
Table 1: Baseline characteristic

Malondialdehyde measurement

To 0.5 ml plasma, 2.5 ml of trichloroacetic acid was added and the tube was left to stand for 10 min at room temperature. After centrifugation at 3500 RPM for 10 min, the supernatant was decanted and the precipitate was washed once with sulfuric acid. Thereafter, 2.5 ml sulfuric acid and 3 ml thiobarbituric acid (TBA) in sodium sulfate were added to the precipitate and the coupling of lipid peroxide with TBA was carried out in a boiling water bath for 30 min. After cooling in cold water, the resulting chromogen was extracted with 4 ml of n-butyl alcohol by vigorous shaking. Separation of the organic phase was facilitated by centrifugation at 3000 RPM for 10 min and its absorbance was determined at the wavelength of 530 nm.

Cu-Zn Superoxide dismutase measurement

This method employs xanthine and xanthine oxidase (XOD) to generate superoxide radicals, which react with 2-(4-iodophenyl)-3-(4-nitrophenol)-5-phenyltetrazolium chloride (I.N.T.) to form a red formazan dye. The superoxide dismutase (SOD) activity is then measured (at 505 nm) by the degree of inhibition of this reaction. One unit of SOD is that which causes a 50% inhibition of the rate of reduction of INT under the conditions of the assay.

Results

In the present study we determined the plasma levels of malondialdehyde, Zinc and erythrocyte Cu-Zn superoxide dismutase in 50 patients with type 2 diabetes mellitus (20 men and 30 women) and 50 control subjects (22 men and 28 women). As shown in table 2 plasma level of Zn and erythrocyte SOD were significantly decreased, and the plasma level of MDA was significantly increased in patients with diabetes compared with controls (p <0.001).

Figure 2
Table 2 : Plasma malondialdehyde, zinc levels and erythrocyte superoxide dismutase activity

Discussion

There are varying reports on changes in plasma lipid peroxidation, zinc and erythrocyte Cu-Zn supetoxide dismutase enzyme activity in patients with type 2 diabetes. Some of the studies shown an increase, whereas others showed a decrease or no significant differences. There are a few reports describing differences in plasma lipid peroxidation, zinc and erythrocyte Cu-Zn superoxide dismutase activity between patients with type 2 diabetes versus controls.

Patients with type 2 diabetes mellitus have increased mortality and morbidity compared with controls, and are more likely to suffer from coronary artery, cerebrovascular and peripheral vascular diseases (23). It has been proposed that oxidative stress may be associated with the pathogenesis of macrovascular complications of type 2 diabetes (5,24). In people with diabetes, the vulnerability to oxidative damage maybe partly attributed to deficient antioxidant micronutrient status, including trace elements. Impairment of zinc (14, 25,26,27) status has been reported as an aggravating factor in the progression of diabetes. Although zinc may influence the processes associated with oxidant stress, the practical consequences of its status have not been studied extensively (28).

The results of this study show that in patients with type 2 diabetes plasma lipid peroxidation (expressed as malondialdehyde) was significantly increased, and that zinc levels were decreased compared with controls (p < 0.05). This study also shows that the erythrocyte superoxide dismutase enzyme activity was decreased in patients with type 2 diabetes compared with controls (p < 0.05).

Some of the previous studies are in agreement with our findings of increased lipid peroxidation and decreased Cu-Zn superoxide dismutase activity in patients with type 2 diabetes (29,30). Sundaram et al. (31) studied patients with type 2 diabetes mellitus and showed an increase in lipid peroxidation from the onset of disease. Study of Nourooz-Zadeh et al. (32) showed that changes in lipid peroxidation were related to the underlying metabolic abnormalities in type 2 diabetes rather than to the onset of complications.

The some studies describe that plasma Zn in type 2 diabetes mellitus patients is decreased (33,34), whereas others show no significant differences (34,35) compared to controls. The results of this study are in agreement with the results of studies showing that plasma Zn levels in patients with type 2 diabete sis significantly decreased (33,34). A possible explanation for this is that there is loss of a large amount of Zn from the body via urine. The source of the Zn that being excreted remains unresolved. There is a concurrent hypozincemia and a decrease in tissue Zn stores. However, it is not clear if this results from hyperzincuria, or from an independent event, an insulin or hyperglycemia related induced loss of Zn from tissue stores. Zn would then be released into the plasma and thereafter excreted. This results in a net loss of total body Zn and eventual hypozincemia.

Possible sources of elevated free radicals in type 2 diabetes include increased production of radical oxygen species, especially from glycation or lipoxidation processes, auto-oxidation of glucose and oxidizing of glucose, and decreased antioxidant defense systems (36). Improvement of glycemic control and supplementation with zinc appears to be a beneficial factor in decreasing lipid peroxidation in patients with diabetes. Prevention of lipid peroxidation may help to delay the development of diabetic complications.

The results of this study also show that in type 2 diabetes mellitus patients, erythrocyte Cu-Zn superoxide dismutase activity is decreased. Other studies have reported that erythrocyte superoxide dismutase activity in this type of patients was either decreased (37,38), increased (39) or no significant differences were observed (40). Possible explanations for our results include reduced antioxidant protection in type 2 diabetes mellitus and/or greatly increased amounts of free radicals that overwhelm the defense system.

Other explanations include decreased activity of Cu-Zn superoxide dismutase related to either increased free radical production causing oxidation followed by denaturing of the enzyme, or alternatively glycation of the enzyme with resulting inhibition of enzymatic activity (41). Furthermore, zinc is a required cofactor for a variety of antioxidant enzymes, particularly superoxide dismutase. Alterations of zinc metabolism resulting in reduced availability of zinc might be expected contribute to tissue damage observed in diabetes (42).

Increased lipid peroxidation, decreased plasma zinc, and reduced erythrocyte Cu-Zn superoxide dismutase activity may predispose patients with type 2 diabetes to cardiovascular complications.We propose that patients with type 2 diadetes may have supraphysiological antioxidants requirements . Supplementation with zinc and other free radical scavengers such as vitamins E and C or foodstuff contianing these such as tomatos, oranges and similars have the potential to boost antioxidant defences and thus may be important for patients with diabetes (43,44).

Acknowledgements

This work was supported by the Golestan University of Medical Sciences.

Correspondence to

Abdoljalal Marjani , Ph.D. Golestan University of Medical Sciences , Gorgan, IRAN Fax : 0098-171-4421289 E-mail : abdoljalal@yahoo.com Tel : 4421651 - 4421653 & 4422652

References

1. Kohen R Chevion S, Schartz R, Berry , EM. (1996) Evaluation of the total low moleculer weight antioxidant activity of plasma in health and diseases: a new approach .Cell Pharmacol 3:355-359
2. Halliwell B. (1997)Antioxidants and human disease : a general introduction. Nutrition Rev 55:S44-S52
3. Halliwell B, Gutteridge JMC. (1989) Free radicals in biology and medicine,2nd edn. Oxford, Oxford University Press.
4. Sies H. (1993) Strategies of antioxidant defence. Eur J Biochem 215: 213-219
5. Baynes JW.(1991) Perspective in diabetes.Role of oxidative stress in development of complication in diabetes. Diabetes 40: 405-41.
6. Hayoz D, Ziegler T, Brunner HR, Ruiz J. (1998) Diabetes mellitus and vascular lesions.Metabolism 47:16-19.
7. Rosen P, Du X, Tschope D. (1998) Role of oxygen derived radicals for a- tocopherol? Mol Cell Biochem 188:103-111.
8. Szaleczky E, Prechl J, Feher J, Somogyi A. (1999) Alterations in enzymatic antioxidant defence in diabetes mellitus - a rationale approach. Postgrad Med J 75: 13-17.
9. Kinlaw WB, Levine AS, Morley JE, et al. (1983) Abnormal zinc metabolism in type 2 diabetes mellitus. Am J Med 75:273 -277.
10. Mocchegianai E, Boemi M, Fumelli P, Fabris N. (1989) Zinc-dependent low thymic hormone level in type 1 diabetes. Diabetes 38:932-937.
11. Mooradian AD, Failla M, Hoogwerf B, Marynuik M, Wylie-Roset J. (1994) Selected vitamins and minerals in diabetes. Diabetes Care 5: 464-478
12. Strain JJ. (1991) Disturbances of micronutrient and antioxidant status in diabetes. Proc Nutr Soc 50: 591-604
13. Anderson RA. (1995) Chromium, glucose tolerance, diabetes and lipid metabolism. J advacement Med 8:37-49
14. Chaumer AB. (1998) Zinc, insulin, and diabetes. J Am Coll Nutr 17:109-115.
15. Anderson RA, Cheng N, Bryden NA, Polansky MM, Cheng N, Chi J, Feng J. (1997) Elevated intakes of supplemental chromium improve glucose and insulin variables in individuals with type 2 diabetes. Diabetes 46:1786-1791
16. Ravina A, Slezak L, Mirsky N, Bryden N, Anderson RA. (1999) Reversal of corticosteroid-induced diabetes mellitus with supplemental chromium. Diabet Med 16 :164-167
17. Ravina A, Slezak L, Mirsky N, Anderson RA. (1999) Control of steroid-induced diabetes with supplemental chromium. J Trace Elem Exptl Med 12:375-378
18. Satoh K. (1978) Serum lipid peroxide in cerebrovascular disorders determined by
19. Clin. Chim. Acta 90:37-43.
20. Barnrnham D, Trinder (1972). Analyst 97
21. Woolliams JA, Wiener G., Anderson PH, McMurray CH. (1983) Research in veterinery science. 34:253-256.
22. Bodor GS, Little RR, Garrett N, et al (1992). Standarization of glycohemaglobin determination in the clinical laboratory: Three years experience. Clin Chem 38:2414-2418.
23. Barnrnham D. Trinder. (1972). Cyanomethhaemoglobin. Analyst 97 ,142.
24. Kannel WB, McGee DL. (1979) Diabetes and cardiovascular disease. The framingham study. JAMA , 2035-2038.
25. Giugliano D, Ceriello A, Paolisso G. (1995) Diabetes mellitus, hypertension and cardiovascular disease :Which role for oxidative stress? Metabolism 44:363-368.
26. Walter RM, Uriu-Hare JY, Olin KL, Oster MH, Anawalt BD, Critchfield JW, Keen CL. (1991) Copper, zinc, manganese, and magnesium complications of diabetes mellitus. Diabetes Care 14:1051-1056
27. Bolstein-Fujii, DiSilvestro RA, Frid D, Katz C, Malarkey W. (1997) Short-term zinc supplementation in women with non-insulin-dependent diabetes mellitus: Effects on plasma 5-nucleotidase activities, insulin-like growth factor I concentrations, and lipoprotein oxidation rates in vitro. Am J Nutr 66:639-642
28. Ruiz C, Alegria, Barbera R, Farre R, Lagarda MJ. (1998) Selenium, zinc and copper in plasma of pateints with type 1 diabetes mellitus in different metabolic control states. J Trace Elem Med Biol 12:91-95
29. DiSilvestro RA. (2000) Zinc in relation to diabetes and oxidative disease. J Nutr 130:1509S-1511S
30. Vanizor B., Orem A.,Karahan SC., et al. (2001) Decreased nitric oxide end-products its relationship with high density lipoprotein and oxidative stress in people with type 2 diabetes without complications. Diabetes Res. Clin.Prac 54:33-39.
31. Cho SY, Park JY, et al. (2002) Alternation of hepatic antioxidation enzyme activities and lipid profile in streptozotocin-induced diabeticrats by supplementation of dandelion water extract.Clin. Chim. Acta 317:109-117.
32. Sundaram RK, Bhaskar A, Vijayalingam S, Viswanathan M, Mohan R, Shanmugasundaram KR. (1996) Antioxidant status and lipid peroxidation in type 2 diabetes mellitus with and without complications. Clin. Sci 90:255-260.
33. Nourooz-Zadeh J, Rahimi A, Tajaddini - Sarmadi J, Tritschler H, Rosen P, Halliwel B, Betteridge DJ. (1997) Relationships between plasma measures of oxidative stress and metabolic control in NIDDM. Diabetologica 40:647- 63.
34. Walter RM, Uriu-Hare JY, Olin KL, et al. (1991) Copper, Zinc, Magnesium status and
35. Diabetes Care14:1050-1056.
36. Evliaoglu O, Kilicaslan N, Uzuncan N, Karaca B, Kocaclebi A, Yensel N, Inci S. (2002) Serum levels of Cu, Zinc, Mg in type 1and 2 diabetic pateints.17.Turkish National Biochemical Congress 285-286.
37. Zargar AH, Shah NA, Massodi SR, et al. (1998) Copper, zinc and magnesium levels in non insulin dependent diabetes mellitus. Postgard Med J 74:665-668.
38. Giugliano D, Ceriello A, Paolisso G. (1995) Diabetes mellitus, hypertension and cardiovascular disease . The role of oxidative stress. Metabolism 44:363-368
39. Cigremis Y, Kose M, Ozgurlu F, Turkoz Y, Egri M. (2003) The investigation of erythrocyte SOD , Cat and GPX antioxidant enzyme level in pateints with type 2 diabetes mellitus. G.U. Journal of Science 16: 239-244.
40. Palanduz S, Ademoglu E, Gokkusu C, Tamer S. (2001) Plasma antioxidants and type 2 diabetes mellitus. Res. Commun Mol Pathol Pharmacol 109:309-318.
41. Turk HM, Sevinc A, Camci C, Cigli A, Buyukberber S, Savli H, Bayraktar N. (2002. Plasma lipid peroxidation products and antioxidant enzyme activities in patients with type 2 diabetes mellitus. Acta Diabetol 39:117-122.
42. Memisogullari R, Taysi S, Bakan E, Capoglu I. (2003). Antioxidant status and lipid peroxidation in type 2 diabetes mellitus, Cell Biochem Funct 21 (3):291-296
43. Hunt J., Wolff SP. (1991) Oxidative glycation and free radical production : A causal mechanism of diabetic complications . Free Rad Res Commun 12:115-123.
44. Sumovski W, Baquerizo H, Rabinovich A. (1992) Oxygen free radical scavenger protect rat islet cells from damage by cytokines. Diabetelogica 32:792-796
45. Dieber-Rotheneder M, Puhl H, Waeg G, Striegl G, Esterbauer H. (1991) Effect of oral supplementation with D- alfa - tocopherol on the vitamin E content of human low density lipoproteins and resistance to oxidation. J Lipid Res 32:1325 -1332.
46. Porkkala-Sarataho E, Nyyssonen K, Salonen JT. (1996) Increased oxidation resistance of atherogenic plasma lipoproteins at high vitamin E levels in non-vitamin E supplemented men. Atherosclerosis 124 :83-94.

Author Information

Abdoljalal Marjani, Ph.D.
Department of Biochemistry and Biophysic, Golestan University of Medical sciences

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