[ association of dietary beta-carotene and beta-cryptoxanthin with the incidence of insulin resistance in adults: Tehran lipid and glucose study]

Background and Objective: Dietary intake of beta-carotene and beta-cryptoxanthin may be associated with reduce the risk of insulin resistance, due to their antioxidant properties. The aim of this study was to determine the relation between dietary intake of beta-carotene and beta-cryptoxanthin and the risk of insulin resistance in adults

Methods: In this prospective cohort study, 938 [421 men and 517 women], aged between 19 to 82 years were selected from among participants of the Tehran Lipid and Glucose Study in Iran. Dietary intake of beta-carotene and beta-cryptoxanthin were determined using a valid and reliable food frequency questionnaire. Fasting serum glucose and insulin were measured at base line and again after a 3-year of follow up. Logistic regression models were used to estimate the occurrence of insulin resistance across tetiles of beta-carotene and beta-cryptoxanthin with adjustment for potential confounding variables

Results: The mean age of participants was 40.7 +/- 12.1 years. beta-carotene was inversely associated with insulin resistance after adjustment for confounder variables [95% CI= 0.25-0.72, OR= 0.42, P-value for trend=0.01]. Also, an inverse association was found between dietary intake of beta-cryptoxanthin and insulin resistance risk [95% CI= 0.30-0.84, OR= 0.51, P-value for trend=0.01]

Conclusion: There was inverse association between dietary intake of beta-carotene and beta-cryptoxanthin and risk of insulin resistance in adults

[The association of red, orange and yellow fruits and vegetables with the incidence of insulin resistance in adults: tehran lipid and glucose study]

Introduction: although previous studies report the relationship of diabetes with various groups of fruits and vegetables, and also an inverse association between insulin resistance with dietary carotenoids and flavonoids, no studies have yet examined the effect of [Fruit and Vegetable] FV subgroups on insulin resistance. The aim of this study was to investigate the association of red, orange and yellow FV, with the 3-year incidence of insulin resistance in adults

Materials and Methods: in this longitudinal study, 940 men and women, aged>19 years were selected from among participants of the Tehran Lipid and Glucose Study. Dietary intakes of fruits and vegetables [FV] were determined using a valid and reliable food frequency questionnaire. Fasting serum glucose and insulin were measured at baseline and again after a 3-year of follow up. Logistic regression models were used to estimate the occurrence of IR across tertiles of color subgroups of FV with adjustment for potential confounding variables

Results: the mean age and body mass index [BMI] of participants were 40.34+/-12.1 years and 26.4+/-4.4 kg/m2 respectively. Mean residual energy adjusted total intakes of FV, red/purple, orange and yellow FV were 503g/d, 172, 108and 104g/d, respectively. Total intake of FV was inversely associated with IR after 3 years of follow up [OR=0.511P for trend=0.018]. and also an inverse association was found between red/purple [OR=0.48 P for trend=0.012], orange [OR=0.34 P for trend=0.001] and yellow [OR=0.34 P for trend=0.011] groups and the occurrence of IR

Conclusion: results of this longitudinal study, found an inverse association between dietary intakes of FV, red/purple, orange and yellow groups and the risk of IR in adults

[Central and general obesity measures for prediction of cardiovascular disease in diabetic adults: Tehran lipid and glucose study]

Considering the high prevalence of diabetes mellitus worldwide and in the Middle East countries and high prevalence of cardiovascular disease [CVD] in diabetic patients, this study aimed to compare different abdominal and central obesity measures, as important risk factors of CVD, for prediction of CVD in Iranian men and women with type 2 diabetes. We followed 1010 patients with type 2 diabetes for a median follow up period of almost 8 years. The hazard ratios [HRs] for CVD were calculated for a 1 standard deviation [SD] change in each anthropometric measure, using Cox proportional regression analysis. A hundred and eighty-eight cardiovascular events occurred in diabetic patients. In the age adjusted model, in diabetic men, waist to hip ratio [WHR], waist to height ratio [WHtR] and waist [WC] were associated significantly with CVD but in the multivariate model, only WHR was associated significantly with CVD. WC in diabetic women and WHtR in both genders were marginally associated with CVD. Central obesity measures were stronger than the general obesity parameter for prediction of CVD in adults with type 2 diabetes mellitus and WHR was the most important anthropometric measure in these patients in both genders

[Relationship between Interleukin 4 and 12 and chronic periapical lesion size]

Chronic dental periapical lesions resulted from chronic inflammatory response to the periapical tissues. Since T-helper [CD4+Y] cells are the prominent cells in these lesions, so the aim of this study was to determine the correlation between the concentration of IL-4 and IL- 12 [most important cytokines for differentiation of T helper 2 and T helper 1 cells, respectively], and the diameter of chronic periapical lesions. Thirty-eight chronic periapical lesions were collected which 18 periapical lesions had diameter of >/= 5 millimeter [case group] and 20 periapical lesions had the diameter <5 millimeter [control group]. Tissue samples were cultured for 72 hours, then ELISA [Enzyme linked immuno-sorbent Assay] was used for determining the concentration of IL-4 and IL- 12 in supernatant fluids. Mann-whitney U and Spearman correlation tests were used to analyze the data. IL-4 and IL- 12 were found in all of samples. There was no significant difference between case and control groups regarding the concentration of IL-4, IL- 12 and IL-4/IL- 12. The only significant correlation was between IL-4 and IL-6 concentration without any regard to the diameter of lesions [P<0.001] [Spearman correlation coefficient=0.593]. It is concluded that in chronic periapical lesions, probably T helper 1 and T helper 2 cells participate in active phases of inflammation and tissue damage equally. This could be resulted from mixed population of bacteria in these lesions