ABSTRACT
Oxidation of low-density lipoprotein [LDL] has been strongly implicated in the pathogenesis of atherosclerosis. The use of antioxidant compounds in dietary food stuffs including vitamin E and rosmarinic acid may lead to the inhibition of production of oxidized LDL and may decrease both the development and the progression of atherosclerosis. The present work investigated the effects of Rosmarinic Acid [RA] on LDL oxidation induced-CuSO4 quantitatively in vitro. Fasting blood samples from normal people after an overnight fasting were collected and then LDL was isolated. LDL was incubated without CuSO4 as control and incubated with CuSO4 and several concentrations of RA [50, 100 and 200 micro M]; and measured the formation of conjugated dienes and Malondialdehyde [MDA]. Inhibition of this Cuinduced oxidation was studied in the presence of several concentrations of RA [50, 100 and 200 micro M]. It was demonstrated that RA is able to decrease CuSO4-induced LDL oxidation. Rosmarinic acid showed a decrease in the formation of [MDA]. Rates of 31.8%, 36.7% and 50.3% were seen at concentrations ranging from 50, 100 and 200 micro M, respectively, against oxidation in vitro. The inhibitory effects of the RA on LDL oxidation were dosedependent at concentrations ranging from 50 to 200 micro M. This study showed that RA at concentrations [50, 100 and 200 micro M] prevented the oxidation of LDL in vitro and it may suggest that they have the similar effect in vivo.
ABSTRACT
Diabetes is a common endocrine disease and its complications are major stimuli for the enhancement of efforts towards its control. At present, glycosylated hemoglobin [HbA1c] is used for long term control of glucose levels in diabetic patients, but due to lack of availability of a standard control method, recent findings suggest that insulin-like growth factor-I [IGF-I] may be used as a biomarker for glycaemic control. The aim of this study was to examine the correlation between IGF-I and glycaemic control measured as fasting plasma glucose [FPG] and HbA1c in Type 1 diabetes
Materials and Methods: we designed a cross-sectional case-control study with systematic random sampling. The study included 26 newly diagnosed patients with Type 1 diabetes [15 male and 11 female; mean age 23.7+/-9.1 years] and 26 healthy controls [9 male and 17 female; mean age 24.1+/-4.4 years]. The concentrations of FPG, IGF-I, HbA1c and IGF-binding protein-3 [IGFBP-3] were measured in both groups. FPG was measured by the enzymatic glucose oxidase method and the colorimetric method was used to measure HbA1c. Determination of serum IGF-I and IGFBP-3 total levels was carried out using immunoassay. P<0.05 was considered as statistically significant
Results: the mean value of IGF-I concentration in Type 1 diabetics was significantly lower than in controls [p<0.05]. No correlation was found between IGF-I and HbA1c in the patients
Conclusion: our data shows that total IGF-I levels are low in patients with Type 1 diabetes. No relationship was found between IGF-I and glycaemic control. However, more detailed intensive studies to further investigate this relationship are recommended