Background: Hypertensive patients are highly susceptible to oxidizability. Although hypertension is common among Iranians, few data are available about lipid oxidation status in the involved people. The aim of this study was to evaluate the relationship between serum lipids levels and susceptibility of lipids to oxidation in hypertensive patients.

Materials and Method: Fasting serum lipids and uric acid (UA) were determined in 100 patients with established hypertension, aged 56 ± 12.6 years. In addition, cooper induced serum lipid oxidation was evaluated. Total cholesterol (TC) and triglycerides were determined by enzymatic method (cholesterol oxidase and glycerol oxidase respectively) and uric acid was measured by uricase method. Test kits were supplied by Zistshimi, and technicon-RA-1000 autoanalyser was used for analysis. Lipid oxidation was followed by the formation of conjugated dienes at 245 nm, in diluted serum, after adding Cu²⁺. Quantitative parameters including lag-time, maximal rate (V-max), and maximal amount of lipid peroxide products (O-D-max) were evaluated. Microsoft Excel was used for preparing kinetic curve of lipid oxidation, and SPSS software (V.11.5) to compare and determine the correlation coefficient between variables.

Results: A significant correlation between Lag-time and serum level of uric acid was found (r=0.34, p=0.009). Also V-max and OD-max were significantly correlated with cholesterol (r=0.46, p=0.001, r=0.52, p=0.001) and triglyceride (r=0.34, p=0.008, r=0.38, p= 0.003).

Conclusion: Our results revealed that in hypertensive patients higher levels of uric acid might have a protective effect against lipid oxidation. Higher levels of serum lipids apparently do not affect lipid oxidizability, but they do influence on the production of higher amount of lipid oxidation products

Background: Chronic complications (e.g. cardiovascular failure) are among the most common problems in diabetics. It is suggested that oxidative stress and lipid peroxidation play a key role in chronic diabetic complications. Supplementation with agents containing antioxidant properties can suppress lipid peroxidation. Many studies confirmed the antioxidant properties of zinc in biological systems. The aim of the present study was to evaluate the effect of zinc supplements on serum lipid oxidizability in diabetic patients.

Materials and Methods: In this clinical trial study, 60 diabetic patients were chosen and randomly divided into two groups. Serum lipid oxidizability and serum zinc level were evaluated in each group before and after zinc supplementation (25.50 mg/day for 2 month). Lipid oxidizability was followed through monitoring the change of conjugated compounds in diluted serum after adding Cu²⁺ by spectrophotometric method. S erum zinc level was measured by atomic absorbance spectrophotometer.

Results: While there was no significant change in the post- supplementation zinc level (25 mg) in the first group, zinc serum level was increased significantly (p<0.002) in the second group. No significant change was seen in serum lipid oxidizability parameters before and after supplementation in two groups. SPSS software (V.11.5) and Wilcoxon test were used for statistical analysis.

Conclusion: Our results indicate that zinc supplementation (25.50 mg) in short period of time has no favorable effect on serum lipid oxidizability in diabetic patients. It seems that zinc dose, duration of treatment and also the patients' condition may affect their response to supplementation.

Background: Lead is a heavy metal that enters the human body through the environmental pollution such as air. Lead contamination is associated with the increased cardiovascular diseases, but the exact mechanism is not fully clarified. The aim of this study was to evaluate the effect of Lead on lipid peroxidation.

Materials and Methods: In this in vitro experimental study, a pool serum was prepared from the healthy subjects and divided into the five fractions. With the addition of Lead, its concentrations in the four samples reached to 0.5, 1, 4 and 5 μM and the fifth sample was used as control. Samples were incubated at 37 °C for one day. Lipid oxidation was induced in each diluted sample by the addition of Cu2+. Oxidation profile was monitored by reading of OD at 245nm. A number of quantitative parameters including the lag-time, maximal rate of oxidation (V-max), and maximal amount of lipid peroxide products (OD-max) were evaluated.

Results: The lag-times in the Lead samples were 4 and 5 µM (158±1.7) and (149.3±1.3) decreased compared to the control (169.7±0.5). Moreover, OD-max in the samples (0.399±0.003) and (0.409±0.008) increased compared to the control (0.373±0.01, P<0.05).

Conclusion: The results show that Lead in high concentrations can trigger serum lipid oxidation. Since the experimental concentrations were in the borderline of toxicity to humans, Lead contamination may increase the risk of cardiovascular disease by enhanced lipid peroxidation.

Background: Diabetes causes disorders in serum trace elements and lipoprotein metabolism. The aim of this study was to determine the effect of co-administration of trientine (Cu chelator agent) and flaxseed oil on serum copper and lipoproteins in diabetic rats.

Materials and Methods: Rats were divided into five groups. Diabetes was induced in 4 groups. Group I received Trientine plus flaxseed oil, group II the standard diet plus Trientine, Group III flaxseed oil and group IV was a diabetic group without treatment. Group V received the standard diet as a control group. After 2 months, the serum Cu2+, TG, Chol, and HDL-C were determined.

Results: In the Trientine plus flaxseed oil group, the serum TG and LDL significantly decreased (P<0.05) compared to the other groups. Also, the serum Chol in supplemented Trientine plus flaxseed oil group decreased (P<0.05) compared to the group which received the standard diet plus Trientine. HDL-C in group received standard diet plus Trientine significantly increased (P<0.05) compared to the other groups. In the group that received Trientine, the serum Cu2+ significantly decreased (P<0.05) compared to the other groups. Moreover, the serum Cu2+ in group received Trientine plus flaxseed oil significantly decreased (P<0.05) compared to the groups that received flaxseed oil and a diabetic group without treatment. In the flaxseed oil group, the serum Cu2+ significantly elevated (P<0.05) compared to the other groups, but this group showed no salient difference (P>0.05) compared to a diabetic group without treatment.

Conclusion: The usage of Cu2+ chelator such as Trientine may reduce the side effects of Cu2+ in diabetes. Co-administration of flaxseed oil plus Trientine significantly reduced the serum of Cu2+ and biochemical parameters such as TG, TC, LDL-C, and Chol in diabetes.

Background: Decreasing the high homocysteine level of serum as one of the risk factors of cardiovascular disease can reduce the occurrence and complications of myocardial infarction. Garlic is identified as one of the main decreasing factors of high homocysteine level. So this study was carried out to determine the garlic effect on high homocysteine level in ischemic heart disease (IHD) patients.

Material and Methods: This observational study was carried out on IHD patients (n=60) attended to heart clinic of Kashan (Isfahan, Iran). Two equal groups of patients (n=30) were administered with 800 mg garlic pills daily for 6 weeks (equvalent to 4gr fresh garlic) and placebo for 6 weeks, respectively. Before and after the  intervention the plasma homocysteine, high density lipoproteine (HDL), triglyceride (TG) and low density lipoproteine (LDL) levels were measured using the ELISA) technique and TG, HDL and enzymatic techniques, respectively.    

Results: The mean age of patients was 60.6±10.1 with 39 male (65%) and 21 female (35%). At the end of study the mean plasma homocysteine level was decreased from 4.6 mol/µl to 4.4 mol/µl; while in placebo group it increased from 4.5 mol/µl to 4.6 mol/µl. However, for the comparison of the effects two drugs on homocysteine, TG, HDL and LDL level, as the confounding factor, no significant difference was seen.  

Conclusion: A daily garlic use of 800 mg for 6 weeks has no effect on serum   homocysteine and lipids levels. The topic requires further research in future.