Apolipoprotein A2 -265 T>C polymorphism interacts with dietary fatty acids intake to modulate inflammation in type 2 diabetes mellitus patients.

OBJECTIVE: Several investigations have been conducted regarding the interaction between Apolipoprotein A2 (APOA2) -265 T>C polymorphism and dietary intake of saturated fatty acids (SFAs) on obesity in healthy individuals or type 2 diabetes mellitus (T2 DM) patients. The aim of the present study is to examine the effect of this interaction on inflammatory markers in T2 DM patients. METHODS: This is a comparative cross-sectional study on 180 T2 DM patients with known APOA2 genotype. Dietary intake was assessed by food-frequency questionnaire and serum levels of inflammatory markers (interleukin [IL]-18, pentraxin 3, and high-sensitivity C-reactive protein [hs-CRP]) were measured. The subjects were dichotomized into "high" and "low" categories, based on the median dietary intake of polyunsaturated fatty acids (PUFAs), monounsaturated fatty acids (MUFAs), and SFAs. The data were analyzed by analysis of covariance multivariate interaction model. RESULTS: In CC genotype, higher median intake of ω-3 PUFAs and MUFAs was associated with decreased serum levels of IL-18 and hs-CRP (P = 0.014 and 0.008, respectively). In T-allele carriers, higher median intake of SFAs was associated with increased serum hs-CRP level (P < 0.001). There was a significant relationship between APOA2 polymorphism and ω-3 PUFA intake on serum IL-18 level (P interaction = 0.03). Moreover, the relationship between this polymorphism and SFA and MUFA intake on serum hs-CRP level was statistically significant (P interaction = 0.03 and 0.024, respectively). CONCLUSIONS: In T2 DM patients, the dietary intake of antiinflammatory fatty acids, such as ω-3 PUFAs and MUFAs, could reduce the inflammatory effects associated with the CC genotype. In addition, proinflammatory fatty acids, such as SFAs, could overcome the antiinflammatory effect of the T-allele. Further studies are needed to confirm these findings.

The interaction between ApoA2 -265T>C polymorphism and dietary fatty acids intake on oxidative stress in patients with type 2 diabetes mellitus.

INTRODUCTION: Apolipoprotein A2 (APOA2) -265T>C polymorphism has been studied in relation to oxidative stress and various dietary fatty acids. Since the interaction between APOA2 polymorphism and dietary fatty acids on oxidative stress has not yet discussed, we aimed to investigate the interaction on oxidative stress in type 2 diabetes mellitus (T2DM) patients. METHODS: The subjects were 180 T2DM patients with known APOA2 genotype, either TT, TC or CC. Superoxide dismutase (SOD) activity was determined by colorimetric method. Total antioxidant capacity (TAC) and serum level of 8-isoprostane F2α were measured by spectrophotometry and ELISA, respectively. Dietary intake was collected through a food frequency questionnaire. Based on the median intake, fatty acids intake was dichotomized into high or low groups. The interaction between APOA2 polymorphism and dietary fatty acids intake was analyzed by ANCOVA multivariate interaction model. RESULTS: Higher than median intake of omega-6 polyunsaturated fatty acids (n-6 PUFA) was associated with increased serum level of 8-isoprostane F2α in subjects with TT/TC genotype (p = 0.004), and higher than median intake of omega-3 polyunsaturated fatty acids (n-3 PUFA) was associated with increased serum SOD activity in CC genotype (p < 0.001). There was a statistically significant interaction between APOA2 polymorphism and n-6 PUFA intake on 8-isoprostane F2α concentration as well as n-3 PUFA intake on serum SOD activity (p-interaction = 0.04 and 0.02, respectively). CONCLUSIONS: The current study shows the interaction between APOA2 polymorphism and dietary fatty acids intake on oxidative stress. More investigations on different populations are required to confirm the interaction.

Dietary ω-3 polyunsaturated fatty acid intake modulates impact of Insertion/Deletion polymorphism of ApoB gene on obesity risk in type 2 diabetic patients.

OBJECTIVES: The goal of the study described here was to determine whether dietary ω-3 polyunsaturated fatty acid (PUFA) intake modulates the association between ApoB Ins/Del polymorphism and obesity in type 2 diabetic patients. METHODS: In this cross-sectional study, 700 patients with type 2 diabetes were recruited in Tehran. Weight and waist circumference (WC) were measured, and body mass index (BMI) was calculated. Dietary intake was assessed using a validated semiquantitative food frequency questionnaire. ApoB genotyping was performed with 8% polyacrylamide gel electrophoresis. RESULTS: We observed a significant interaction between Ins/Del genotype and dietary ω-3 PUFA intake with respect to BMI, WC, and obesity risk in both unadjusted (P = 0.007, P = 0.001, and P = 0.021, respectively) and adjusted (P = 0.007, P = 0.04, and P = 0.002, respectively) samples. Thus, the carriers of the Del allele were only associated with lower BMI (P = 0.01) and WC (P = 0.002) among individuals with high ω-3 PUFA intake (≥0.6% of energy), but not in those with low ω-3 PUFA intake (<0.6%). Also, when dietary ω-3 PUFA was <0.6%, general obesity risk in carriers of the Del allele was about 1.6 times higher than that of Ins/Ins homozygotes (odds ratio = 1.59, 95% confidence interval: 1.05-2.52, P = 0.039). But with high ω-3 PUFA intake (≥0.6%), the risk was 0.46 times lower (odds ratio = 0.46, 95% confidence interval: 0.25-0.79, P = 0.003). Moreover, a similar interaction was observed in central obesity only in men after adjustment for confounder variables (P = 0.041). CONCLUSIONS: These findings support the hypothesis that a diet high in ω-3 PUFA (≥0.6%) can decrease the obesity risk in carriers of the Del allele of ApoB gene.

Effects of Iron Supplementation With and Without Docosahexaenoic Acid on the Cardiovascular Disease Risk Based on Paraoxonase-1, hs-CRP, and ApoB/ApoA-I Ratio in Women with Iron Deficiency Anemia.

Numerous studies have demonstrated that tissue deposition of iron following prolonged high dose of oral supplementation for treatment of iron deficiency anemia (IDA) leads to body iron overload and oxidative stress, which starts the process of atherosclerosis. This study aimed to determine the effect of iron supplementation in combination with docosahexaenoic acid (DHA) on the cardiovascular disease risk based on paraoxonase-1 (PON-1), high-sensitivity C-reactive protein (hs-CRP), and ApoB/ApoA-I ratio in women with IDA. In this randomized controlled trial, 76 women with IDA, aged 15-45 years, were included. The patients were randomly assigned to receive 500 mg of DHA supplement or placebo with an iron tablet, once daily for 12 weeks. The participants were assessed by measurement of the serum iron, ferritin, PON-1, hs-CRP levels, and the ApoB/ApoA-I ratio at the beginning and end of study. Serum hs-CRP decreased in the DHA-supplemented group (p = 0.036), and ApoA-I decreased in the placebo group (p = 0.013). No significant difference was detected for the serum PON-1 concentration and the ApoB/ApoA-I ratio in two groups. Iron supplementation combined with DHA may have favorable effects on serum hs-CRP in women with IDA.

Effect of spinach aqueous extract on wound healing in experimental model diabetic rats with streptozotocin.

BACKGROUND: Chronic ulcer is still a serious issue for diabetic patients. Diabetes is a prevalent cause of ulcer regeneration delay and (or) disruption. Since Spinacia oleracea extract contains compounds with anti-oxidative and anti-inflammatory effects, this may be effective in accelerating the healing process of ulcers, especially diabetic ulcers. Hence, this study examined the effect of Spinacia oleracea aqueous extract on ulcer regeneration in an experimental animal model. RESULTS: Macroscopic examination of the wounds of the control group and spinach aqueous extract group between 7 and 21 days compared with diabetic group, significant changes were observed (P < 0.05). On microscopic examination, epithelial tissue formation, formation of granulation tissue and new blood vessels in the spinach aqueous extract group and non-diabetic group compared to the diabetic group showed significant improvements (P < 0.05). Also, significant differences in vascular endothelial growth factor were observed between groups on days 3 and 7 (P < 0.05). CONCLUSION: The Spinacia oleracea aqueous extract can be effective in regenerating diabetic ulcers. It affects the speed and structure of the ulcer. © 2015 Society of Chemical Industry.

Effect of DHA-rich fish oil on PPARγ target genes related to lipid metabolism in type 2 diabetes: A randomized, double-blind, placebo-controlled clinical trial.

BACKGROUND: The beneficial effects of omega-3 polyunsaturated fatty acids on lipid levels are well documented. However, the related molecular mechanisms are widely unknown. Omega-3 polyunsaturated fatty acids are natural ligand for peroxisome proliferator-activated receptor γ (PPARγ). OBJECTIVE: The aim of this study was to evaluate the effect of docosahexaenoic acid (DHA)-rich fish oil supplementation on modulation of some PPARγ-responsive genes related to lipid metabolism. METHODS: Patients with type 2 diabetes were randomly assigned to consume either DHA-rich fish oil (containing 2400 mg/d fish oil; DHA: 1450 mg and eicosapentaenoic acid: 400 mg) or placebo for 8 weeks. Lipid profile and glycemic control parameters as well as the gene expression of PPARγ, liver x receptor-a, ATP-binding cassette A1, and CD36 in peripheral blood mononuclear cells were measured at baseline and after 8 weeks. RESULTS: DHA-rich fish oil supplementation resulted in decreased triglycerides (TG) level compared with placebo group, independently of the baseline value of TG (all patients (P = .003), hypertriglyceridemic subjects (P = .01), and normotriglyceridemic subjects (P = .02)). Moreover, a higher reduction in TG level was observed in hypertriglyceridemic subjects, comparing to normotriglyceridemic subjects with DHA-rich fish oil supplementation (P = .01). Other lipid parameters as well as the expression of PPARγ, liver x receptor-a, ATP-binding cassette A1, and CD36 were not affected by DHA-rich fish oil supplementation. Only in hypertriglyceridemic subjects, DHA-rich fish oil supplementation upregulated CD36 expression, compared with the placebo group (P = .01). CONCLUSIONS: DHA-rich fish oil supplementation for 8 weeks increased CD36 expression in hypertriglyceridemic subjects, which might result to higher reduction in TG level, comparing with normotriglyceridemic subjects. However, this finding should be investigated in further studies.

Impact of Vitamin A Supplementation on Disease Progression in Patients with Multiple Sclerosis.

BACKGROUND: Many studies have shown that active vitamin A derivatives suppress the formation of pathogenic T cells in multiple sclerosis (MS) patients. The aim of the present study is to determine the impact of vitamin A on disease progression in MS patients. METHODS: A total of 101 relapsing-remitting MS (RRMS) patients were enrolled in a 1-year placebo-controlled randomized clinical trial. The treated group received 25000 IU/d retinyl palmitate for six month followed by 10000 IU/d retinyl palmitate for another six month. The results of the expanded disability status scale (EDSS) and multiple sclerosis functional composite (MSFC) were recorded at the beginning and the end of the study. The relapse rate was recorded during the intervention. Patients underwent baseline and follow up brain MRIs. RESULTS: The results showed "Mean ± SD" of MSFC changes in the treated group was (-0.14 ± 0.20) and in the placebo group was (-0.31 ± 0.19). MSFC was improved significantly (P < 0.001) in the treatment group. There were no significant differences between the "Mean ± SD" of EDSS changes in the treated (0.07 ± 0.23) and placebo (0.08 ± 0.23) groups (P = 0.73). There were also no significant differences between the "Mean ± SD" of annualized relapse rate in the treated group (-0.36 ± 0.56) and placebo (-0.53 ± 0.55) groups (P = 0.20). The "Mean ± SD" of enhanced lesions in the treatment (0.4 ± 1.0) and in the placebo (0.2 ± 0.6) groups were not significantly different (P = 0.26). Volume of T2 hyperintense lesions "Mean ± SD" was not significantly different between treatment (45 ± 137) and placebo (23 ± 112) groups after intervention (P = 0.23). CONCLUSION: Vitamin A improved total MSFC score in RRMS patients, but it did not change EDSS, relapse rate and brain active lesions.

Docosahexaenoic Acid-Rich Fish Oil Supplementation Improves Body Composition without Influence of the PPARγ Pro12Ala Polymorphism in Patients with Type 2 Diabetes: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial.

BACKGROUND: The aims of this research were to investigate (1) the impact of docosahexaenoic acid (DHA)-rich fish oil supplementation on body composition, plasma adiponectin level, and peroxisome proliferator-activated receptor γ (PPARγ) gene expression, and (2) whether the effect of DHA-rich fish oil supplementation on the aforementioned variables is modulated by PPARγ Pro12Ala polymorphism. METHODS: We genotyped PPARγ Pro12Ala polymorphism in subjects with type 2 diabetes mellitus (T2DM). Ala carriers and non-Ala carriers were randomly assigned to DHA-rich fish oil or placebo intake for 8 weeks. RESULTS: Glycemic control was not affected by the intervention. The supplementation with DHA-rich fish oil decreased waist circumference (p < 0.001), body fat mass (p = 0.01), body fat percent (p = 0.04), and viscera fat rating (p = 0.02) as well as trunk fat mass (p = 0.04). Weight, body mass index, fat-free mass, adiponectin level, and PPARγ gene expression changes showed no significant difference. No gene-diet interaction was found on body composition, adiponectin level, and PPARγ gene expression. CONCLUSIONS: DHA-rich fish oil supplementation favorably modulated body composition in patients with T2DM and could be useful to reduce visceral obesity. However, the PPARγ Pro12Ala polymorphism did not influence the changes in the desired variables.

Vitamin A supplementation and serum Th1- and Th2-associated cytokine response in women.

AIMS AND BACKGROUND: T helper (Th)1/Th2 immune response has been linked to obesity-related immune disorders. It has been proven that retinoid active derivates improve immunity via regulating Th1/Th2 balance. However, there is not a well-identified report of direct effect of vitamin A on Th1/Th2 balance in obesity. The present study aimed to investigate the possible role of vitamin A on serum Th1/Th2 response in obese women. MATERIALS AND METHODS: A randomized double-blind placebo-controlled trial was conducted on 84 obese (n = 56; body mass index [BMI] 30-39.9 kg/m(2)) and nonobese (n = 28; BMI 18.5-24.9 kg/m(2)) women. Obese women were randomly allocated to receive either vitamin A (retinyl palmitate 25,000 IU/d) or placebo. Nonobese women also received 25,000 IU/d retinyl palmitate. Anthropometric variables were assessed and serum interleukin (IL)-1ß, tumor necrosis factor (TNF)-α, IL-4, and IL-13 were analyzed before and 4 months after intervention. RESULTS: Vitamin A treatment significantly reduced serum concentrations of IL-1ß in obese vitamin A-treated subjects (from 3.58 ± 0.36 to 2.45 ± 0.23 pg/ml, p < 0.006). Serum concentrations of IL-4 and IL-13 were also reduced in obese and nonobese vitamin A-treated subjects (p < 0.05). A significant reduction in IL-1ß/IL-4 ratio in the obese vitamin A-treated group was also observed (p = 0.03). CONCLUSIONS: Decline in serum concentrations of IL-1ß and IL-1ß/IL-4 ratio in obese women suggests that vitamin A is capable of regulating the immune system and possibly reducing the risk of autoimmune disease in this group. Further studies are needed to explore the possible underlying mechanisms.

Vitamin A supplementation, serum lipids, liver enzymes and C-reactive protein concentrations in obese women of reproductive age.

BACKGROUND: High-dose vitamin A influences glucose and lipid profile; however, the possible effects of moderate doses (25,000 IU/d) are conflicting. We aimed to compare the effect of vitamin A supplementation on several anthropometric and biochemical variables between obese and non-obese women. METHODS: This study was performed on 84 women among whom 56 were obese (body mass index [BMI] 30-35 kg/m(2)) and 28 were non-obese (BMI 18.5-24.9 kg/m(2)). Obese women were randomly divided into two groups: one group received 25,000 IU/d retinyl palmitate and another group received placebo. The third group was age-matched non-obese women who received 25,000 IU/d retinyl palmitate. At baseline and four months after intervention, fasting blood glucose (FBG), lipid profile, C-reactive protein (CRP) and liver enzymes were evaluated. RESULTS: Baseline concentrations of serum FBG and triglyceride in the obese vitamin A-treated group were significantly higher compared with the other groups (P = 0.004 and 0.007, respectively). A significant increase in serum FBG (P = 0.026), total cholesterol (TC) (P = 0.004) and low-density lipoprotein cholesterol (LDL-C) (P = 0.016) in the non-obese group and a significant decrease in serum high-density lipoprotein cholesterol (HDL-C) (P = 0.001) in the obese group was observed. Serum CRP increased significantly in the obese vitamin A-treated group (P = 0.03) and serum aspartate transaminase increased significantly in the obese and non-obese groups after vitamin A supplementation (P = 0.008 and 0.001, respectively). CONCLUSIONS: Treatment with 25,000 IU/d vitamin A induced a mild elevation in serum lipids, CRP and liver enzymes in obese and non-obese women. Considering the other information about possible side-effects of excess vitamin A, use of vitamin A in this dose and duration should be considered with caution.

The effect of vitamin A supplementation on stimulated T-cell proliferation with myelin oligodendrocyte glycoprotein in patients with multiple sclerosis.

BACKGROUND: Multiple sclerosis (MS) is an autoimmune disease whereby myelin sheath of the central nervous system is destroyed. Vitamin A is known to play a role in the immune system. It has been recognized that some metabolites of vitamin A can be used effectively to treat experimental autoimmune encephalomyelitis (EAE). AIMS: The effect of vitamin A as retinyl palmitate on T-cell proliferation in MS patients. SETTING AND DESIGN: This study is a double blind clinical trial of two test groups over a period of 6 months. MATERIALS AND METHODS: Thirty five multiple sclerosis (MS) patients were divided into two groups. One group received 25,000 IU/day vitamin A (as retinyl palmitate) and the other group were administered a placebo. The peripheral blood mononuclear cells (PBMCs) were separated and stimulated with myelin oligodendrocyte glycoprotein (MOG) and phytohemagglutinin (PHA) before and after the trial period. BrdU calorimetric assay was performed to measure cell proliferation. STATISTICAL ANALYSIS: Analysis of covariance (ANCOVA) and paired t-test were used to analyze the data. RESULTS: Observations showed statistical significant differences in the reduction of cell proliferation in the presence of MOG and fetal calf serum (FCS) in the culture medium, between patients receiving vitamin A and the placebo (P = 0.046). Although, this difference was not significant between the two vitamin A and placebo groups in MOG treatment with human serum, a decrease was observed in the group of patients taking vitamin A supplements (P = 0.019). Phytohemagglutinin did not cause any change in cell proliferation between the two groups. CONCLUSION: The results suggest supplementation with retinyl palmitate in patients with MS reduce MOG stimulatory effects on T-cells.

The effect of vitamin A supplementation on thyroid function in premenopausal women.

OBJECTIVE: Vitamin A and its retinoid derivates play an important role in regulation of normal growth and development. Vitamin A has been shown to regulate thyroid hormone metabolism and inhibit thyroid-stimulating hormone (TSH) secretion via down regulation of TSH-ß gene expression; however, the effect of vitamin A on thyroid function in obese individuals who are at higher risk of subclinical hypothyroidism is still unclear. In the present study we investigate the impact of vitamin A supplementation on thyroid function in obese women. METHOD: A 4-month randomized, double blind controlled trial was conducted among 84 healthy women aged 17-50 years old: 56 were obese (body mass index [BMI] 30-35 kg/m(2)) and 28 were nonobese (BMI 18.5-24.9 kg/m(2)). Obese women were randomly allocated to receive either vitamin A (25,000 IU/d retinyl palmitate) or placebo. Nonobese women received vitamin A. At baseline and 4 months after intervention, serum concentrations of TSH, total thyroxine (T4), total triiodothyronine (T3), retinol-binding protein (RBP), and transthyretin (TTR) were measured. RESULTS: Baseline concentrations of thyroid hormones, RBP and TTR were not significantly different between groups. Vitamin A caused a significant reduction in serum TSH concentrations in obese (p = 0.004) and nonobese (p = 0.001) groups. Serum T3 concentrations also increased in both obese and nonobese vitamin A-treated groups (p < 0.001). Serum T4 decreased in all 3 groups after treatment. The results showed a significant reduction in serum RBP in the obese group after vitamin A supplementation (p = 0.007), but no significant change was seen in serum TTR. CONCLUSIONS: Serum TSH concentrations in vitamin A-treated subjects were significantly reduced; therefore, vitamin A supplementation might reduce the risk of subclinical hypothyroidism in premenopausal women.

Regular consumption of vitamin D-fortified yogurt drink (Doogh) improved endothelial biomarkers in subjects with type 2 diabetes: a randomized double-blind clinical trial.

BACKGROUND: Endothelial dysfunction has been proposed as the underlying cause of diabetic angiopathy that eventually leads to cardiovascular disease, the major cause of death in diabetes. We recently demonstrated the ameliorating effect of regular vitamin D intake on the glycemic status of patients with type 2 diabetes (T2D). In this study, the effects of improvement of vitamin D status on glycemic status, lipid profile and endothelial biomarkers in T2D subjects were investigated. METHODS: Subjects with T2D were randomly allocated to one of the two groups to receive either plain yogurt drink (PYD; containing 170 mg calcium and no vitamin D/250 mL, n1 = 50) or vitamin D3-fortified yogurt drink (FYD; containing 170 mg calcium and 500 IU/250 mL, n2 = 50) twice a day for 12 weeks. Anthropometric measures, glycemic status, lipid profile, body fat mass (FM) and endothelial biomarkers including serum endothelin-1, E-selectin and matrix metalloproteinase (MMP)-9 were evaluated at the beginning and after the 12-week intervention period. RESULTS: The intervention resulted in a significant improvement in fasting glucose, the Quantitative Insulin Check Index (QUICKI), glycated hemoglobin (HbA1c), triacylglycerols, high-density lipoprotein cholesterol (HDL-C), endothelin-1, E-selectin and MMP-9 in FYD compared to PYD (P < 0.05, for all). Interestingly, difference in changes of endothelin-1, E-selectin and MMP-9 concentrations in FYD compared to PYD (-0.35 ± 0.63 versus -0.03 ± 0.55, P = 0.028; -3.8 ± 7.3 versus 0.95 ± 8.3, P = 0.003 and -2.3 ± 3.7 versus 0.44 ± 7.1 ng/mL, respectively, P < 0.05 for all), even after controlling for changes of QUICKI, FM and waist circumference, remained significant for endothelin-1 and MMP-9 (P = 0.009 and P = 0.005, respectively) but disappeared for E-selectin (P = 0.092). On the contrary, after controlling for serum 25(OH)D, the differences disappeared for endothelin-1(P = 0.066) and MMP-9 (P = 0.277) but still remained significant for E-selectin (P = 0.011). CONCLUSIONS: Ameliorated vitamin D status was accompanied by improved glycemic status, lipid profile and endothelial biomarkers in T2D subjects. Our findings suggest both direct and indirect ameliorating effects of vitamin D on the endothelial biomarkers. TRIAL REGISTRATION: ClinicalTrials.gov: NCT01236846.

Effects of carnitine and coenzyme Q10 on lipid profile and serum levels of lipoprotein(a) in maintenance hemodialysis patients on statin therapy.

INTRODUCTION: Dyslipidemia and high serum lipoprotein(a) are among the risk factors for cardiovascular diseases in hemodialysis patients. Statins as a first line of therapy in hyperlipidemia does not always reduce the serum lipoprotein(a) level. Several studies have reported the lipid-lowering effects of carnitine and coenzyme Q10 in hemodialysis patients. This study was designed to investigate the effects of carnitine and coenzyme Q10 on serum lipid profile and lipoprotein(a) level in maintenance hemodialysis patients. MATERIALS AND METHODS: This was a randomized placebo-controlled trial. We studied on hemodialysis patients who were on treatment with atorvastatin or lovastatin to assess the efficacy of supplement therapy. They were divided into 4 groups to receive carnitine, coenzyme Q10, both carnitine and coenzyme Q10, and placebo. After a 3-month experiment, blood samples were collected to measure serum levels of lipoprotein(a), triglyceride, total cholesterol, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol. RESULTS: Fifty-two hemodialysis patients, 27 men and 25 women, completed the course of the study. Three months after supplement therapy, serum levels of lipoprotein(a) reduced significantly in the carnitine, coenzyme Q10, and combination groups compared to the baseline values and the 3-month value of lipoprotein(a) in the placebo group (P = .01). Serum levels of triglyceride and other lipoproteins did not significantly alter. CONCLUSIONS: Our study showed that supplementation with carnitine and coenzyme Q10 could reduce serum levels of lipoprotein(a) in maintenance hemodialysis patients treated with statins.

Comparison of the effects of simultaneous administration of vitamin C and omega-3 fatty acids on lipoproteins, apo A-I, apo B, and malondialdehyde in hyperlipidemic patients.

BACKGROUND: Control of hyperlipidemia is vital in patients with cardiovascular disease (CVD). Omega-3 fatty acids (n-3FAs) have desirable effects on serum triglyceride (TG) levels, thrombosis, and arrhythmia, but lead to increases in serum low-density lipoprotein (LDL) and apo-B as well. OBJECTIVE: To determine and compare the effects of administration of n-3FAs, vitamin C (VitC) and n-3FAs + VitC on the serum levels of LDL, apoB, other serum lipids, and malondialdehyde (MDA). The present study was performed in Tehran University of Medical Sciences from 2000 to 2001. DESIGN: In a double-blind, placebo trial of parallel design, 68 hyperlipidemic patients [total cholesterol (TC) and TG greater than 200 mg/dL] were randomly assigned to receive daily 500 mg VitC, 1 g n-3FAs, 500 mg VitC + 1 g n-3FAs, or placebo (control) for 10 weeks. Fasting blood samples were collected at the beginning and at the end of the period. TG, TC, LDL-cholesterol-C (LDL-C), and high-density lipoprotein-cholesterol (HDL-C) were measured enzymatically, VitC and MDA colorimetrically, and apo-B and apo-A-I immunoturbidometrically. The pattern of food consumption, socio-economic, and anthropometric indices were determined; there was no significant change in these indices during the study. RESULTS: There was a significant difference in the blood VitC level at the end of the study in comparison to the initial value in the VitC (p = 0.001) and VitC + n-3FAs (p = 0.027) groups. Similarly, the serum TG level at the end of study was significantly different from the initial value in the n-3FAs group (p = 0.002) and also from the final value in the control group (p = 0.013). In the VitC group, there was a significant decrease in TC (p = 0.004), apo-B (p = 0.005), and MDA (p = 0.015) at the end of study as compared to the respective initial values. There was also a significant increase in blood VitC compared to the control value (p = 0.018) and a significant decrease in MDA compared to the n-3FAs group (p = 0.034). At the end of study, in the n-3FAs group, there was a significant (p = 0.04) and a marginally significant decrease (p = 0.05), respectively, in TG/HDL and apo-B levels as compared to the initial values, and the TG/HDL ratio showed a significant decrease as compared to the control group (p = 0.047). CONCLUSION: Simultaneous administration of n-3FAs and VitC had no beneficial effects on the lipid profile of hyperlipidemic patients, but 1 g purified n-3FAs daily for 10 weeks is a beneficial supplement for decreasing TG without any increase in LDL-C, apo-B or MDA. Administration of 500 mg VitC for more than 10 weeks might decrease significantly TC and apo-B in hyperlipidemic patients.