Lifestyle advice follow-up improve glycemic control, redox and inflammatory status in patients with type 2 diabetes
© Mahdad et al.; licensee BioMed Central. 2014
Received: 18 March 2014
Accepted: 9 December 2014
Published: 17 December 2014
The dietary composition associated to physical activity could play a significant role in improving insulin sensitivity and reducing risk of diabetes and its complications. This study was designed to investigate whether glycemic control, redox and inflammatory status impairments in patients with type 2 diabetes (T2D), were improved after 90 (d90) and 180 (d180) days follow-up of nutritional advices.
Patients with T2D (n = 85) aged of 50 ± 8 years (Female/Male, 45/40), treated with oral antidiabetics (OAD) alone, with a body mass index (BMI) of 26 ± 2, were recruited. At the beginning of the study (d0), patients were instructed to follow-up nutritional advices adapted to T2D, and 30 to 45 min of walking per day. Assays were realized at d90 and d180 of follow-up. Data were compared by student ‘t’ test and Pearson’s correlation coefficients were determined between biochemical parameters and nutritional advices follow-up.
Reduced glycated haemoglobin (HbA1c), glucose and total cholesterol (TC) were noted in patients with T2D, at d90 and d180 compared to d0. Thiobarbituric acid reactive substances (TBARS) and hydroperoxyde levels were lower at d90 and d180 than d0. Serum nitric oxide (NO) was decreased at d180 compared to d0 and d90. In erythrocytes, superoxide dismutase (SOD) activity increased by 7% at d180 vs d0. Moreover, activity of glutathione peroxidase (GPx) enhanced (P < 0.05), whereas that of glutathione reductase (GRed) decreased (P < 0.001) at d90 vs d0. Resistin values were lower at d180 than d0 and d90 (P < 0.001). A progressive decrease in tumor necrosis factor-α (TNF-α) was observed at d90 and d180 vs d0.
Nutritional advices associated to physical activity improve glycemic control, serum TC, redox and inflammatory status in T2D, in particular after 3 months of counseling. However, these results need to be supported with a longer dietary treatment and more rigorous control during the follow-up.
KeywordsType 2 diabetes HbA1c Redox status Resistin TNF-α
Dietary and lifestyle approaches have a high potential for the primary prevention of type 2 diabetes (T2D) . This disease is a multistage process that begins as insulin resistance (IR), characterized by body inability to use properly its own insulin, and ends with exhaustion of the insulin-producing pancreatic ß-cells, thereby leading to hyperglycaemia . Several factors are implicated in T2D development, including obesity, family history, physical inactivity and inherited factors . Moreover, dietary composition could play a significant role in improving insulin sensitivity and reducing risk of diabetes and its complications . Indeed, cardiovascular diseases (CVD) are the major cause of morbidity and mortality in T2D , knowing that cardiovascular risk is threefold higher in T2D than in general population . In Algeria, the prevalence of T2D was about 10% in 2010 .
In T2D, the oxidative stress (OS) acts as a mediator of IR, and its progression to glucose intolerance and installation of the pathology, possibly contributes to the rise of several micro- and macro-vascular complications associated with diabetes . In conditions of severe OS, cell damage occurs with decreased pancreatic ß-cell function, which is due to low expression of antioxidant enzymes .
However, clinical studies have also shown that specific antioxidant concentrations in plasma and erythrocytes of diabetes patients are reduced . Indeed, superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT) activities scavenging reactive oxygen species (ROS), were decreased in patients with T2D. Thus, the improvement in oxidative stress status can contribute to diabetes management .
Inflammation is considered to be a key regulator of T2D pathogenesis, but the mechanism, by which it acts, is still unknown. Tumor necrosis factor (TNF-α) is an inflammatory cytokine implicated in metabolic disorders, including obesity and IR. Several studies have shown high levels of interleukin-6 (IL-6) and TNF-α among individuals with clinically diagnosed diabetes . Moreover, authors reported increased resistin levels in association with obesity and IR in T2D , whereas other study observed no change in resistin levels under such conditions . Data have shown that circulating resistin levels were involved in promoting adiposity, but had no effect on IR degree. These observations suggested that the role of resistin in the pathogenesis of diabetes remained controversial .
The purpose of the present study was to investigate whether TD2 impaired glycemic control, redox and inflammatory status, and their improvement after 3 and 6 months follow-up of nutritional advices.
This study was conducted from November 2009 to June 2011 in the Hospital University Establishment (HUE) (Internal Medicine) and polyclinics of Oran (west Algeria). Patients with T2D since 9 ± 3 years (n = 85) (sex ratio F/M, 45/40), with a mean age of 50 ± 8 years treated during 8 ± 1 years with oral antidiabetics (OAD as biguanides and/or sulfamides) only, with a body mass index (BMI) (kg/m2) of 26 ± 2, fasting glycemia ≥ 7 mmol/L, triglyceridemia < 2 mmol/L, cholesterolemia < 5 mmol/L and low-density lipoproteins-cholesterol (LDL-C) < 3.5 mmol/L.
Characteristics of patients with type 2 diabetes
Sex ratio (F/M)
50 ± 8
70 ± 9
26 ± 2
Waist circumference (cm)
89 ± 8
Diabetes duration (year)
9 ± 3
1.68 ± 0.65
9.8 ± 1.9
Total cholesterol (mmol/L)
4.16 ± 0.70
1.15 ± 0.57
1.20 ± 0.33
This study was approved by the Institutional Ethic Committee for Research on Human Subjects of the University of Oran. The protocol and the aim of the study were explained to the patients and the investigation was conducted with their written informed consent.
Nutritional counseling was designed to cover the nutritional needs and maintain life quality of patients. The recommended daily energy intake was 2000 Kilocalories (Kcal) with 250 g of carbohydrates distributed over different meals in the day i.e. breakfast, morning snack, lunch, afternoon snack and dinner. The advice given promoted the consumption of fish meal, fruits and vegetables (FFV). Consumption of a dairy product at all the three main meals daily, vegetables (2 times/d), fruits (2–3 times/d), olive oil (2 table spoons/d), whole bread daily at each meal, fish (2–3 times/week), with limited eggs consumption (4–5 eggs/week) and moderate amounts of red or white meats, sources of animal proteins, at lunch and dinner were recommended. Moreover, patients were instructed for 30 to 45 min of walking per day. The follow-up was performed at d90 and d180.
Height and weight were performed using stadiometer and balance (Weighting Scale ZT 220, China). Waist circumference (WC) was measured mid-way between the lateral lower rib margin and the iliac crest (ombilicus).
Blood was drawn after a 12-hour overnight fasting by antecubital venipuncture, at d0, d90 and d180, after lifestyle advices. Serum and erythrocytes were collected by low-speed centrifugation at 1000 g for 15 min. Serum was preserved with 0.1% ethylene–diamine-tetraacetic acid-disodium (Na2-EDTA). Erythrocytes were washed two times with 0.9% sodium chloride (NaCl) solution, and four times with cold water. Erythrocytes lysates were preserved with 0.5% sodium dodecylsulfate (SDS, Sigma, USA). Serum and erythrocytes lysates were stored at -70°C until assays.
Serum glucose was measured by enzymatic colorimetric test (kit Biocon, Germany). Serum insulin was determined by an in vitro enzyme-linked immunosorbent assay (ELISA) (kit Abcam, Cambridge, USA) for the quantitative measurement of human serum insulin and proinsulin. HbA1c was estimated by chromatographic spectophotometric test (kit Biocon, Germany). Homeostatic model assessment insulin resistance (HOMA-IR) index (IR = fasting serum insulin (μU/mL) × fasting plasma glucose (mmol/L)/22.5) was determined .
Serum total cholesterol (TC), triglycerides (TG) and uric acid (UA) levels were measured by enzymatic colorimetric tests (kits Biocon, Germany). Albumin was determined by colorimetric method (Kit Biolabo, France).
Serum and erythrocytes lipid peroxidation was estimated by measuring thiobarbituric acid reactive substances (TBARS) . The colored complex formed between malondialdehyde (MDA) and thiobarbituric acid (TBA) had maximum absorbance at 532 nm. The serum hydroperoxyde concentrations were determined by measuring cumin hydroperoxyde (EqCuOOH) by comparison of the straight line . The absorbance was measured at 560 nm. Oxidized proteins were estimated by measuring carbonyl concentrations, using the 2,4-dinitrophenylhydrazine . The absorbance was measured at 270 nm. Nitric oxide (NO) determination was performed using Griess reagent (sulfamide and n-naphtyl-ethylene diamine) . Serum was clarified by zinc sulfate solution and nitrate (NO3) was then reduced to nitrite (NO2) by cadmium, overnight, at 20°C, under shaking. Serum was added to the Griess reagent and incubated for 20 min at 24°C. The absorbance was measured at 540 nm.
SOD, GPx (EC 184.108.40.206) and GRed (EC 220.127.116.11) activities in erythrocytes were determined by kits (Sigma, USA). SOD activity was assessed at 450 nm by measuring the dismutation of superoxide radicals generated by xantine oxidase and hypoxantine. The oxidation of glutathione (GSH) to oxidized glutathione (GSSG) was catalysed by GPx, which was then coupled to recycling of GSSG back to GSH utilizing GRed and NADPH (reduced β-nicotinamide adenine dinucleotide phosphate) (Sigma, USA). The activity was measured by the decrease in absorbance caused by the oxidation of NADPH at 340 nm using an extinction coefficient (εmM) of 6.22 for NADPH. Catalase (CAT) (EC. 18.104.22.168) catalyses the decomposition of hydrogen peroxide to water and oxygen at 240 nm .
TNF-α was assayed by enzyme immunometric assay (EIA) kit (Cayman Chemical’s ACE™ EIA kit, USA) permitting TNF-α measurements within the range of 0–250 pg/ml. The lower limit of detection was 3.9 pg/mL for TNF-α. The human resistin was determined by EIA (SPI Bio – Bertin Pharma Branch kit, France). The normal range was established for 8.1 ± 4.1 ng/ml.
The non-parametric student ‘t’ test (STATISTICA 5.0.) was used to compare mean differences between d0, d90 and d180. Relationships between all the biochemical parameters and the nutritional advices follow-up were determined by the Pearson’s correlation coefficient. P values <0.05 were considered significant.
Among 85 patients with T2D, at d0 and after 3 months of nutritional advices (d90), only 35 patients completed this study at d180. The remaining patients became hypertensive and/or were treated by insulin. There was no significant difference in studied parameters when related to a gender.
Clinical and biochemical parameters in TD2 patients after nutritional advices
n = 85
n = 85
n = 35
70 ± 7
70 ± 9
69 ± 9
26 ± 2
25 ± 2
24 ± 2
Waist circumference (cm)
89 ± 8
86 ± 7
88 ± 5
9.8 ± 1.9
6.4 ± 1.7 ***
8.4 ± 1.0§
7.71 ± 1.50
6.27 ± 1.56**
6.76 ± 0.77ǂ§
13.10 ± 4.32
12.53 ± 4.26
8.75 ± 1.20
Total cholesterol (mmol/L)
4.16 ± 0.70
3.47 ± 1.10**
3.09 ± 1.30§§
1.15 ± 0.57
0.73 ± 0.35 **
1.26 ± 0.53ǂǂ
Compared to d0, serum TC concentrations were lowered by 17% and 26% at d90 and d180, respectively. Moreover, TG concentrations in patients with T2D were reduced by 36% at d90 compared to d0, whereas, these values increased by 42% at d180 compared to d90 (Table 2).
Redox status and inflammation markers in T2D patients after lifestyle advices
n = 85
n = 85
n = 35
6.53 ± 1.90
4.87 ± 1.31 *
4.90 ± 1.77§
0.31 ± 0.06
0.19 ± 0.06 ***
0.16 ± 0.06§§§
Carbonyls (nmol/mg prot)
1.07 ± 0.73
0.85 ± 0.41
0.80 ± 0,35
2.26 ± 0.41
1.91 ± 0.36
1.57 ± 0.14§ǂ
Uric acid (μmol/L)
229.52 ± 67.10
238.10 ± 77.12
308.33 ± 118.52§
36.60 ± 12.50
51.00 ± 7.00 ***
46.35 ± 5.43
2430.11 ± 824.38
2045.37 ± 710.10
2622.00 ± 541.14ǂ
3.14 ± 1.98
5.17 ± 2.63 *
5.45 ± 3.08
1.97 ± 0.61
1.15 ± 0.45 **
1.52 ± 0,60
CAT (U/g Hb)
18124.00 ± 5549.01
15128.00 ± 5067.32
16099.52 ± 5354.30
15.78 ± 2.24
13.95 ± 0.82
5.10 ± 1.20§ǂǂ
3.44 ± 1.19
2.33 ± 0.81*
1.89 ± 0.9§
In erythrocytes, SOD activity increased by 7% in T2D at d180 vs d0. There was no significant change in CAT activity of T2D patients during the follow-up, whereas, increased GPx activity by 39% was observed at d90 compared with d0. However, GRed activity was reduced by 42% at d90 vs d0.
Resistin values were 3- and 2.7-fold lower, in T2D at d180 than d0 and d90 respectively. Moreover, TNF-α concentrations were 1.5- and 1.8-fold decreased at d90 and d180, after nutritional advices than d0.
Correlation studies between HbA1c, HOMA-IR and resistin and various parameters in T2D patients
The aim of the present study was to determine if the nutritional advices improved glycemic control, redox and inflammatory status in T2D patients treated with OAD only.
After nutritional advices based on eating FFV and carbohydrates distribution at each meal, T2D patients showed no significant difference in BMI and WC, whereas, large studies showed that excessive abdominal fat deposition is an important risk factor for T2D  and that high WC is a better predictor than BMI .
Lowering HbA1c in T2D decreased the CVD risk and all mortality causes . After d90 and d180 of nutritional advices, HbA1c and glucose values lowered significantly in T2D, showing relationships between glycemic control and BMI. This improvement was probably due to the recommended FFV consumption associated with physical activity practice. Indeed, a moderate effect of regular physical exercise with a mean HbA1c decrease, without significant weight loss, was observed despite favorable changes in body weight composition . Similar results showed, that three months consumption of fruits, reduced blood glucose and HbA1c levels, whereas, no significant changes were noted in BMI and WC . At d180 vs d90, increased serum glucose level was noted, without change in serum insulin concentrations, whereas HOMA-IR had a tendency to decrease but not significantly. The most plausible explanation, for this phenomenon, was that d180 corresponded to summer period with many festive meals, and during holidays, people were customarily physically inactive and were prone to forget diet recommendations. Indeed, it has been shown that seasons can influence fasting glucose and HbA1c in T2D patients . Our T2D patients were instructed to consume 2 table spoons of olive oil daily and fish intake 2-times weekly. Indeed, data have shown that n-3 poly-unsaturated fatty acids (PUFAs) from fish may decrease IR through several mechanisms, such as a decrease in plasma TG, and perhaps small dense lipoproteins , and the consumption of mono-unsaturated FA (MUFA)-rich diet improve IR in T2D .
A high intake of dry or fresh vegetables and fruits was associated with a better control regulation of lipid profile . In the present study, nutritional advices reduced serum TC and TG at d90 vs d0. Indeed, dietary MUFA (oleic acid) decreased LDL-C and TG concentrations, without lowering high-density lipoproteins-cholesterol (HDL-C) . Moreover, the improved lipid profile was probably due to the daily regular 30 to 45 min walking by our patients. Indeed, physical activity decreased TG and LDL particles and enhanced HDL-C .
T2D is associated with increased oxidative stress, contributing to this pathogenesis , by increasing serum TBARS  and hydroperoxides . At d180 and d90 compared to d0, TBARS and hydroperoxides concentrations were significantly reduced in our T2D patients. Furthermore, the lowered lipid peroxidation could be due to the improved glycemic control, and therefore to a lesser oxidative stress, showing relationships between TBARS and HbA1c. Likewise, consumption of fruits and vegetables, rich in antioxidants, could play an important role in protecting our patients from oxidative stress generated by T2D.
A high level of plasma protein carbonyls has been reported in T2D patients , and can also originate from a loss of albumin antioxidant capacity, knowing that plasma albumin, via its thiol groups, is the main extracellular antioxidant molecule . In our study, serum carbonyl values had a tendency to decrease, whereas serum albumin value was enhanced, after lifestyle advices, suggesting that improved glycemic control can reduce oxidative stress, and therefore carbonyl amounts, without altering albumin properties.
Some controversies about the NO role are noted in the IR pathogenesis . Moreover, NO, a metabolite of L-arginine to L-citrulline conversion by endothelial NO synthase, has a favorable effect on inflammation , and oxidative stress . A decrease in NO values at d180 vs d0 and d90 was noted and was positively correlated with IR and serum resistin.
Hyperuricaemia is associated with IR , which is mediated partly by inflammation and oxidative stress . However, our results showed, at d180 vs d0, that high UA level was inversely related to HOMA-IR and resistin. Indeed, this result suggested that uric acid value was efficient to reduce IR and inflammation in T2D.
Besides the important lipid peroxidation in T2D patients, an increase in SOD activity was observed in such individuals . In our T2D patients, erythrocytes SOD activity increased at d180 vs d0 (P < 0.05), suggesting a possible adaptative response, probably due to a high production of superoxide anion (O2−), which would lead to an increased hydrogen peroxide (H2O2) production . This latter has been reported to inactivate SOD, and superoxide anion radical inactivates CAT , and GPx . However, there was no significant difference in the both enzyme activities at d180 vs d0. In our T2D patients, GRed activity was lower, while GPx was higher, at d90 vs d0. In contrast, diabetic complications involved lowered GPx activity, which could also be due to decreased glucose-6-phosphate dehydrogenase activity, in erythrocytes , leading to reduced NADPH production, required for recycling processes of GSSG to GSH, which was the GPx substrate .
There is a genetic evidence to support relationships between human inflammation, in particular resistin and obesity or IR . In the present study, lowered serum resistin values, at d180 vs d90 and d0, were observed, and were positively correlated with IR. Moreover, TNF-α was reduced significantly in T2D, after nutritional advices, compared to the beginning of the study. High levels of inflammatory cytokines appear in early stage of T2D, and predict the development of this disease, through lowering insulin sensitivity . Indeed, a highly significant relationship between resistin and TNF-α, and a negative correlation between resistin and SOD were observed. Moreover, observational studies have shown an inverse association between dietary total antioxidant capacity and inflammation markers , whereas, n-3 PUFA supplementation may potentially affect these markers, in patients with T2D . In our study, recommended FFV could contribute probably to decreased serum resistin and TNF- α, and thus protecting the organism from proinflammatory cytokines deleterious effects.
The nutritional advices follow-up i.e. FFV consumption, and carbohydrates distribution at each meal, associated to a regular physical activity practice, improve glycemic control and serum total cholesterol in T2D. Moreover, a low lipid peroxidation and a high antioxidant defense are noted, involving a less oxidative stress induced by T2D, on the one hand, and reduced serum resistin and TNF-α are in favor of a low progression to complications, on the other hand. However, these results need to be supported with a regular dietary treatment and more rigorous control during the follow-up.
This study was funded by the National Agency of Health Research (Agence Nationale de Recherche en Santé) of the Ministry of Higher Education and Scientific Research (National Research Program N° 02/15/02/04/186). The authors acknowledged Dr A. Bekkara, president of “La maison du diabétique” of Oran, for his helpful in T2D patient recruitment.
- Gillies CL, Abrams KR, Lambert PC, Cooper NJ, Sutton AJ, Hsu RT, Khunti K: Pharmacological and lifestyle interventions to prevent or delay type 2 diabetes in people with impaired glucose tolerance: systematic review and meta-analysis. BMJ 2007, 334: 1–9. 10.1136/bmj.39063.689375.55View ArticleGoogle Scholar
- American Diabetes Association: Diagnosis and classification of diabetes mellitus Diabetes Care 2008, 31(1):S55-S60. 10.2337/dc08-S055View ArticleGoogle Scholar
- Mann JI: Nutrition recommendations for the treatment and prevention of type 2 diabetes and the metabolic syndrome: an evidenced-based review. Nutr Rev 2006, 64: 422–427. 10.1111/j.1753-4887.2006.tb00227.xView ArticlePubMedGoogle Scholar
- Zander E, Kerner W: Cardiovascular risk factors in type 1 and type 2 diabetes: common conventional and diabetes-related risk variables? In Vascular Involvement in Diabetes: Clinical, Experimental and Beyond. Edited by: Cheta D. Karger, Basel; 2005. 1: 264–271Google Scholar
- Selvin E, Marinopoulos S, Berkenblit G, Rami T, Brancati FL, Powe NR, Golden SH: Meta-analysis: glycosylated hemoglobin and cardiovascular disease in diabetes mellitus. Ann Intern Med 2004, 141: 421–431. 10.7326/0003-4819-141-6-200409210-00007View ArticlePubMedGoogle Scholar
- Institut National de Santé Publique 2009: Enquête diabète. Ministère de la santé, de la population et de la réforme hospitalière, Alger. Étude de l’épidémiologie du diabète de type 2 dans des populations endogames de l’ouest Leban Sci J 2012, 13(2):17–26.Google Scholar
- Negre-Salvayre A, Salvayre R, Augé N, Pamplona R, Portero-Otin M: Hyperglycemia and glycation in diabetic complications. Antioxid Redox Signal 2009, 11(12):3071–3109. 10.1089/ars.2009.2484View ArticlePubMedGoogle Scholar
- Valko M, Leibfritz D, Moncol J, Cronin MTD, Mazur M, Telser J: Free radicals and antioxidants in normal physiological functions and human disease. Int J Biochem Cell Biol 2007, 39(1):44–84. 10.1016/j.biocel.2006.07.001View ArticlePubMedGoogle Scholar
- Sekeroglu MR, Sahin H, Dulger H, Algun E: The effect of dietary treatment on erythrocyte lipid peroxidation, superoxide dismutase, glutathione peroxidase, and serum lipid peroxidation in patients with type 2 diabetes mellitus. Clin Biochem 2000, 33: 669–674. 10.1016/S0009-9120(00)00190-9View ArticlePubMedGoogle Scholar
- Maritim AC, Sanders RA, Watkins JB: Diabetes, oxidative stress and antioxidants. A review. J Biochem Mol Toxicol 2003, 17: 24–38. 10.1002/jbt.10058View ArticlePubMedGoogle Scholar
- Goyal R, Faizy AF, Siddiqui SS, Singhai M: Evaluation of TNF-α and IL-6 levels in obese and non-obese diabetics: pre and post-insulin effects. North Am J Med Sci 2012, 4(4):180–184. 10.4103/1947-2714.94944View ArticleGoogle Scholar
- Silha JV, Krsek M, Skrha JV, Sucharda P, Nyomba BL, Murphy LJ: Plasma resistin, adiponectin and leptin levels in lean and obese subjects: correlations with insulin resistance. Eur J Endocrinol 2003, 149: 331–335. 10.1530/eje.0.1490331View ArticlePubMedGoogle Scholar
- Hasegawa G, Ohta M, Ichida Y, Obayashi H, Shigeta M, Yamasaki M, Fukui M, Yoshikawa T, Nakamura N: Increased serum resistin levels in patients with type 2 diabetes are not linked with markers of insulin resistance and adiposity. Acta Diabetol 2005, 42: 104–109. 10.1007/s00592-005-0187-xView ArticlePubMedGoogle Scholar
- Laudes M, Oberhauser F, Schulte DM, Freude S, Bilkovski R, Mauer J, Rappl G, Abken H, Hahn M, Schulz O, Krone W: Visfatin/PBEF/Namptand resistin expressions in circulating blood monocytes are differentially related to obesity and type 2 diabetes in humans. Horm Metab Res 2010, 42: 268–273. 10.1055/s-0029-1243638View ArticlePubMedGoogle Scholar
- Abdin AA, Baalash AA, Hamooda HE: Effects of rosiglitazone and aspirin on experimental model of induced type 2 diabetes in rats: focus on insulin resistance and inflammatory markers. J Diabetes Complicat 2010, 24: 168–178. 10.1016/j.jdiacomp.2009.01.005View ArticlePubMedGoogle Scholar
- Quintanilha AT, Packer L, Szyszlo JM, Racanelly TL, Davies KJ: Membrane effects of vitamin E deficiency bioenergetic and surface charge density studies of skeletal muscle and liver mitochondria. Ann NY Acad Sci 1982, 393: 32–47. 10.1111/j.1749-6632.1982.tb31230.xView ArticlePubMedGoogle Scholar
- Eymard S, Genot C: A modified xylenol orange method to evaluate formation of lipid hydroperoxides during storage and processing of small pelagic fish. Eur J Lipid Sci Technol 2003, 105: 497–501. 10.1002/ejlt.200300768View ArticleGoogle Scholar
- Levine RL, Garland D, Oliver CN, Amici A, Climent I, Lenz AG, Ahn BW, Shaltiel S, Stadtman ER: Determination of carbonyl content in oxidatively modified proteins. Methods Enzymol 1990, 186: 464–478. 10.1016/0076-6879(90)86141-HView ArticlePubMedGoogle Scholar
- Cortas N, Wakid N: Determination of inorganic nitrate in serum and urine by a kinetic cadmium-reduction method. Clin Chem 1990, 36: 1440–1443.PubMedGoogle Scholar
- Aebi H: Catalase. In Methods of enzymatic analysis. 2nd edition. Edited by: Berg Meyer H. Verlag Chemie, Weinheim; 1974:673–684. 10.1016/B978-0-12-091302-2.50032-3View ArticleGoogle Scholar
- Koh-Banerjee P, Wang Y, Hu FB, Spiegelman D, Willett WC, Rimm EB: Changes in body weight and body fat distribution as risk factors for clinical diabetes in US men. Am J Epidemiol 2004, 159(12):1150–1159. 10.1093/aje/kwh167View ArticlePubMedGoogle Scholar
- Wang Y, Rimm EB, Stampfer MJ, Willett WC, Hu FB: Comparison of abdominal adiposity and overall obesity in predicting risk of type 2 diabetes among men. Am J Clin Nutr 2005, 81(3):555–563.PubMedGoogle Scholar
- Brinke RT, Dekker N, de Groot M, Ikkersheim D: Lowering HbA1c in type 2 diabetics results in reduced risk of coronary heart disease and all-cause mortality. Prim Care Diabetes 2008, 2: 45–49. 10.1016/j.pcd.2007.12.004View ArticlePubMedGoogle Scholar
- Duclos M, Gautier JF: Physical activity and type 2 diabetes mellitus. Méd Mal Métaboliques 2009, 3(1):31–38. 10.1016/S1957-2557(09)70101-4View ArticleGoogle Scholar
- Hegde SV, Adhikari PMN, D’Souza V: Effect of daily supplementation of fruits on oxidative stress indices and glycaemic status in type 2 diabetes mellitus. Complement Ther Clin Pract 2013, 19: 97–100. 10.1016/j.ctcp.2012.12.002View ArticlePubMedGoogle Scholar
- Chen HS, Jap TS, Chen RL, Lin HD: A prospective study of glycemic control during holiday time in type 2 diabetic patients. Diabetes Care 2004, 27(2):326–330. 10.2337/diacare.27.2.326View ArticlePubMedGoogle Scholar
- Richard D, Bausero P, Schneider C, Visioli F: Polyunsaturated fatty acids and cardiovascular disease. Cell Mol Life Sci 2009, 66(20):3277–3288. 10.1007/s00018-009-0085-4View ArticlePubMedGoogle Scholar
- Risérus U, Willett WC, Hu FB: Dietary fats and prevention of type 2 diabetes. Prog Lipid Res 2009, 48(1):44–51. 10.1016/j.plipres.2008.10.002View ArticlePubMedPubMed CentralGoogle Scholar
- Fidanza F, Alberti A, Lanti M, Menotti A: Mediterranean adequacy index correlation with 25-years mortality from coronary heart disease in the seven countries study. Nutr Metab Cardiovasc Dis 2004, 14: 254–258. 10.1016/S0939-4753(04)80052-8View ArticlePubMedGoogle Scholar
- Sacks FM: Dietary fat, the Mediterranean diet, and health: reports from scientific exchanges, 1998 and 2000. Introduction. Am J Med 2002, 113(9B):1–4. 10.1016/S0002-9343(01)00985-8View ArticleGoogle Scholar
- Tall AR: Exercise to reduce cardiovascular risk. How much is enough? N Engl J Med 2002, 347(19):1522–1524. 10.1056/NEJMe020117View ArticlePubMedGoogle Scholar
- Mehrotra S, Ling KL, Bekele Y, Gerbino E, Earle KA: Lipid hydroperoxide and markers of renal disease susceptibility in African–Caribbean and Caucasian patients with Type 2 diabetes mellitus. Diabet Med 2001, 18: 109–115. 10.1046/j.1464-5491.2001.00416.xView ArticlePubMedGoogle Scholar
- Savu O, Ionescu-Tirgoviste C, Atanasiu V, Gaman L, Papacocea R, Stoian I: Increase in total antioxidant capacity of plasma despite high levels of oxidative stress in uncomplicated type 2 diabetes mellitus. J Int Med Res 2012, 40(2):709–716. 10.1177/147323001204000235View ArticlePubMedGoogle Scholar
- Nourooz-Zadeh J, Tajaddini-Sarmandi J, McCarthy S, Betteridge DJ, Wolff SP: Elevated levels of authentic plasma hydroperoxides in NIDDM. Diabetes 1995, 44(9):1054–1058. 10.2337/diab.44.9.1054View ArticlePubMedGoogle Scholar
- Telai A, Cakatery U, Kayali R, Erdogan C, Orhan Y, Sivas A, Akçay T: Oxidative protein damage in plasma of type 2 diabetic patients. Horm Metab Res 2000, 32: 40–43. 10.1055/s-2007-978584View ArticleGoogle Scholar
- Faure P, Troncy L, Lecomte M, Wiernsperger N, Lagarde M, Ruggiero D, Halimi S: Albumin antioxidant capacity is modified by methylglyoxal. Diabetes Mediab 2005, 31: 169–177. 10.1016/S1262-3636(07)70183-0View ArticleGoogle Scholar
- Lucotti P, Setola E, Monti LD, Galluccio E, Costa S, Sandoli EP, Fermo I, Rabaiotti G, Gatti R, Piatti P: Beneficial effects of a long-term oral l-arginine treatment added to a hypocaloric diet and exercise training program in obese, insulin-resistant type 2 diabetic patients. Am J Physiol Endocrinol Metab 2006, 291: E906-E912. 10.1152/ajpendo.00002.2006View ArticlePubMedGoogle Scholar
- Clapp BR, Hingorani AD, Kharbanda RK, Mohamed-Ali V, Stephens JW, Vallance P, MacAllister RJ: Inflammation induced endothelial dysfunction involves reduced nitric oxide bioavailability and increased oxidant stress. Cardiovasc Res 2004, 64: 172–178. 10.1016/j.cardiores.2004.06.020View ArticlePubMedGoogle Scholar
- Monastyrskaya E, Folarin N, Malyshev I, Green C, Andreeva L: Application of the nitric oxide donor SNAP to cardiomyocytes in culture provides protection against oxidative stress. Nitric Oxide 2002, 7: 127–131. 10.1016/S1089-8603(02)00107-6View ArticlePubMedGoogle Scholar
- Sautin YY, Nakagawa T, Zharikov S, Johnson RJ: Adverse effects of the classic antioxidant uric acid in adipocytes: NADPH oxidase-mediated oxidative/nitrosative stress. Am J Physiol Cell Physiol 2007, 293: C584-C589. 10.1152/ajpcell.00600.2006View ArticlePubMedGoogle Scholar
- Furukawa S, Fujita T, Shimabukuro M, Iwaki M, Yamada Y, Nakajima Y, Nakayama O, Makishima M, Matsuda M, Shimomura I: Increased oxidative stress in obesity and its impact on metabolic syndrome. J Clin Invest 2004, 114: 1752–1761. 10.1172/JCI21625View ArticlePubMedPubMed CentralGoogle Scholar
- Bandeira SM, Guedes S, da Fonseca LJ, Pires AS, Gelain DP, Moreira JC, Rabelo LA, Vasconcelos SM, Goulart MO: Characterization of blood oxidative stress in type 2 diabetes mellitus patients: increase in lipid peroxidation and SOD activity. Oxid Med Cell Longev 2012, 819310: 1–13. 10.1155/2012/819310View ArticleGoogle Scholar
- Kono Y, Fridovich I: Superoxide radical inhibits catalase. J Biol Chem 1982, 257(10):5751–5754.PubMedGoogle Scholar
- Blum J, Fridovich I: Inactivation of glutathione peroxidase by superoxide dismutase radical. Arch Biochem Biophys 1985, 240: 500–508. 10.1016/0003-9861(85)90056-6View ArticlePubMedGoogle Scholar
- Jain SK, Robert M: Effect of glycemic control, race (White vs Black), and duration of diabetes on reduced glutathione content in erythrocyte of diabetes patients. Metabolism 1994, 43(3):306–309. 10.1016/0026-0495(94)90097-3View ArticlePubMedGoogle Scholar
- Smith SR, Bai F, Charbonneau C, Janderova L, Argyropoulos G: A promoter genotype and oxidative stress potentially link resistin to human insulin resistance. Diabetes 2003, 52(7):1611–1618. 10.2337/diabetes.52.7.1611View ArticlePubMedGoogle Scholar
- Festa A, D’Agostino R Jr, Tracy RP, Haffner SM: Elevated levels of acute-phase proteins and plasminogen activator inhibitor-1predict the development of type 2 diabetes: the insulin resistance atherosclerosis study. Diabetes 2002, 51(4):1131–1137. 10.2337/diabetes.51.4.1131View ArticlePubMedGoogle Scholar
- Brighenti F, Valtuena S, Pellegrini N, Ardigò D, Del Rio D, Salvatore S, Piatti P, Serafini M, Zavaroni I: Total antioxidant capacity of the diet is inversely and independently related to plasma concentration of high-sensitivity C-reactive protein in adult Italian subjects. Br J Nutr 2005, 93(5):619–625. 10.1079/BJN20051400View ArticlePubMedGoogle Scholar
- Oliver E, Mc Gillicuddy F, Phillips C, Toomey S, Roche HM: Postgraduate Symposium. The role of inflammation and macrophage accumulation in the development of obesity-induced type 2 diabetes mellitus and the possible therapeutic effects of long-chain n-3 PUFA. Proc Nutr Soc 2010, 69(2):232–243. 10.1017/S0029665110000042View ArticlePubMedGoogle Scholar
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