Iranian Journal of

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Diabetes is a common endocrine disease with complications such as retinopathy, nephropathy and neuropathy which has its monitoring through biomarkers desirable. At present, glycosylated hemoglobin (HbAic) is used for monitoring the long term control of glucose levels in diabetic patients. However, absence of a standardized range, has led to investigations that recently have suggested insulin-like growth factor-I (IGF-I) as a good biomarker for monitoring blood glucose levels in diabetics. The aim of this study was to examine the correlation between IGF-I and HbAic in Type 1 diabetes.
Methods: We designed a cross-sectional case-control study. The study composed of 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). Levels of fasting plasma glucose (FPG), HbA]C) IGF-I and IGF-binding protein-3 (IGFBP-3) were measured in both groups. FPG was measured by enzymatic glucose oxidase method and the colorimetric method was used to measure HbAlc. Determination of total serum levels of IGF-I and IGFBP-3 were done using immunoassay methods. P-value<0.05 was considered as statistically significant.
Results: The mean value of IGF-I concentrations in type 1 diabetics was significantly lower than controls (p< 0.05). A reverse correlation was observed between IGF-I and HbAic. Conclusion: The study indicates that in poorly controlled diabetics, levels of FPG and HbAic rise concurrent with a drop in levels of IGF-I decreases. Our study also showed a significant correlation between IGF-I and HbAie. Therefore, IGF-I could be indirectly used as a biomarker for controlling glucose levels in diabetics.

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Background: Leptin, a peptide hormone, is the product of "ob" Gene. Leptin regulate body weight and composition through reducing appetite and energy expenditure in rodents and humans. The aim of this study was to evaluate differences in expression of Leptin Gene in different tissues of streptozotocin induced diabetic rats.
Methods: 40 Sprague Dawely rat were selected. Intra peritoneal injection was carried out in 20 rats and another 20 rats were used as control. After injection of 60mg/kg Streptozotocin, animals were transformed into diabetic. Glucose was measured by glucose oxidase method. Leptin and insulin were measure by commercially available immunoassay kits. After one week treatment, different tissues including adipose tissues, Spleen, epidydimis, and Liver of both control and experimental animals were dissected. For investigation of any changes of the Leptin gene expression in different tissues, RNA was extracted using Trizo1 method. By using RT-PCR technique, Leptin cDNA and β-actin cDNA as internal control were constructed and PCR was carried out. The RT-PCR products were detected on 2% agarose gel using electrophoresis.
Results: Mean serum levels of Leptin was 5.23± 0.45 ng/ml before injection of streptozotocin and markedly decreased in STZ induced diabetic rats to 0.79±0.25 ng/ml. This decrease was statistically significant P<0.05). There was a direct and significant correlation between leptin and insulin in streptozotocin-induced diabetic rats (r=0.37, P<0.05 ) while, this was reverse in control rats ( r= -0.28, P<0.05). Using RT-PCR method, Leptin gene expression in different tissues including fat epidydimis, liver, and spleen showed that the intensity of leptin band with 452 bp was decreased in diabetic rats in comparison to normal rats. Actin Gene expression was identified in PCR products having 403 bp and the intensity was constant in both groups. The reduction rates of "ob" mRNA in fat epidydimis tissue in STZ diabetic rats was remarkable in comparison to Spleen and Liver.
Conclusion: It is speculated that Leptin gene could be under regulation of insulin dependent mechanism in diabetic rats and by modulating Leptin gene expression in diabetic patients, it may be useful in clinical practices.

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Background: Diabetes is a common endocrine disease in human kind. In most type II diabetic patients, obesity and overweight status account as the serious health problems worldwide and variety of endocrine factors well known that have regulatory role in weight balance and body composition including Leptin and IGF-I factor. The aim of this study was to examine the correlation between Leptin and IGF-I in type II diabetics and controls.
Methods: As a case- control study, 38 type 2 diabetics (20 males and 18 female with mean age 49.22) and 46 healthy controls (16 males and 30 females with mean age 49.52) are recruited. We measured the concentrations of FPG, IGF-I, HbA1C and IGFBP-3 in both groups. FPG was measured by enzymatic glucose oxidase method and Hb Gold analyzer HPLC was used to measure HbA1C. Determination of Leptin, IGF-I, IGFBP-3 and Insulin concentrations were carried out using ELIZA method. P< 0.05 was considered as statistically significant.
Results: The mean of BMI and age were not significantly different in both groups. The mean serum levels of IGF-I, Leptin, Insulin, FPG and HbA1c concentrations in type II diabetics were significantly higher than controls (P< 0.05). In males, the mean serum levels of Leptin were statistically lower than in females in both groups. There was a strong correlation between IGF-I and IGFBP-3, Leptin and insulin, IGF-I and age, and BMI with FPG in both patients and controls (P< 0.05). A reverse correlation was observed between IGF-I and HbA1c in patients and controls (P< 0.05).
Conclusion: It is speculated that based on this findings, Leptin and IGF-I system could have regulatory roles in body composition and fat content particularly in obese and overweight diabetic patients and have significant correlation with Insulin, glucose, BMI and age.

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Background: Type 2 diabetes mellitus is a common metabolic disorder witht increasing prevalence is increasing worldwide. C-Reactive Protein (CRP) is a marker of systemic inflammation and an independent risk factor for cardiovascular disease (CVD). The aim of this study was to elucidate the correlation between glycemic control and systemic inflammation by measuring serum CRP levels.

Methods: In this cross sectional study 136 patients with type 2 diabetes mellitus (69 females, 67 males) were recruited. In addition to measurement of CRP levels by highly sensitive methods and measurement of hemoglobin A₁C effects of influencing factors on the CRP level was considered. Fasting plasma glucose was determined via the glucose oxidase method, HbA_1C via HPLC, serum lipid profile enzymatically and hs-CRP with sandwich immunoassay method.

Results: The mean concentrations of CRP levels in these patients (5.2 ± 4.8 mg/L) were higher than normal range and in women greater than men (6.4 ± 5.5 vs. 3.9 ± 3.6 mg/L). Before adjusting for influencing factors the association between hs-CRP levels and hemoglobin A_1C was negative but not statistically significant (r= -0.15, P=0.07). After adjusting, the association was negative and significant. (r= -0.22, P= 0.02). In this study the relation between hs-CRP and lipid profile was also determined.  There was no significant relationship between the levels of hs-CRP and total cholesterol, LDL-C and HDL-C. A positive correlation between hs-CRP with serum triglyceride and triglyceride / HDL ratio was observed. However, the correlation was not significant.

Conclusion: These results demonstrate that hs-CRP levels is influenced with multiple factors, and increased hs-CRP levels in patients with type 2 diabetes mellitus can not be explained with hyperglycemia alone.

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Background: Leptin is a peptide strongly correlated with adiposity and is a potential determinant of obesity and its complications. The aim of this study was to evaluate the correlation between serum leptin levels and different anthropometric indices among obese women.

Methods: This analytical descriptive study consisted of 106 women with different grade of obesity (BMI ³ 25 kg/m²) and 38 women with normal weight (BMI ≤ 25 kg/m²).serum leptin and glucose levels were measured via enzyme immunoassay and glucose oxidase methods respectively.

Results: The mean (± SE) serum leptin concentrations  in apparently healthy women with normal weight ,overweight, obese grade I, and obese grade II were 6.88 ± 0.56, 39.30 ± 1.73, 46.60 ±1.04, and 48.22± 3.31 ng/ml respectively. There was a dramatic increase in serum Leptin concentration when the BMI was increased. There was statistically significant differences between all groups in serum leptin concentration (P<0.001). There was a direct and significant correlation between serum leptin concentration and BMI in obese subjects (r= 0.736, P< 0.001). There was no significant correlation between leptin with age, and leptin with WHR neither in normal weight group nor in different grades of obesity groups.

 Conclusion: Our findings showed that the serum leptin levels continuously raised with increasing degree of obesity and among different anthropometric indices serum leptin concentration has significant correlation with BMI. 

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Background: Resistin, an adipocyte secreted factor, has been suggested to link obesity with type 2 diabetes and insulin resistance in rodent models but its relevance to human diabetes remains uncertain. The aim of this study was to investigate the relationship between serum resistin concentrations with insulin resistance and obesity indices in type 2 diabetes and non-diabetic obese subjects.

Methods: As a case- control study 35 obese subjects with type 2 diabetes (age, 44.60 ± 6.39yr BMI, 34.23±3.92 kg/m2) and 35 obese non-diabetics (age, 43.14±9.13yr BMI, 35.54 ± 4.07 kg/m2) are recruited. Fasting lipid profile was measured by enzymatic methods. NycoCard HbA1c Kit was used to measure HbA1c.The Serum resistin, insulin and glucose levels were measured by an enzyme immunoassay using a commercially available kit and glucose oxidase methods respectively. The insulin resistance index was calculated from fasting glucose and insulin by the homeostasis model assessment (HOMA-IR) formula.

Results: The mean of insulin resistance index (HOMA-IR), HbA1c, diastolic blood pressure, triglyceride and fasting glucose in diabetics were significantly higher than non-diabetics subjects (P<0.05). Serum resistin concentrations were not different between diabetics and non-diabetics obese subjects but were significantly higher in women as compared to men (8.15±4.40 vs. 5.97±2.31 in non-diabetic) and (7.46±3.98 vs. 5.51±3.98 in diabetic) in both groups. Serum resistin was not significantly related to variables measured in both groups. In control group only, we observed a significant and negative correlation between diastolic blood pressure and resistin (r = -0.381 P = 0.024).

Conclusion: Serum resistin concentrations were not significantly different between type 2 diabetes and non-diabetic obese subjects and resistin is unlikely to be a major link between obesity and diabetes in humans.

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Background: Adiponectin is an adipose tissue-derived hormone that low levels of this hormone are associated with obesity, insulin resistance, and type 2 diabetes. The aim of this study was to compare the serum levels of adiponectin in diabetic and non-diabetic obese individuals.

Methods: As a cross-sectional study 35 obese individuals with type 2 diabetes mellitus and 35 non-diabetic obese subjects were enrolled. Two groups were matched for age, gender and body mass index. Fasting lipid profile was measured via the enzymatic methods. The NycoCard HbA1c Kit was used to measure HbA1c.The Serum Adiponectin, insulin and glucose levels were measured via an enzyme immunoassay, using a commercially available kit and glucose oxidase methods, respectively. The HOMA and QUICKI indices were used to determine insulin resistance and insulin sensitivity, respectively.

Results: The mean of insulin resistance index (HOMA-IR), HbA1c, diastolic blood pressure, triglyceride and fasting glucose in diabetes were significantly higher than non-diabetics (P<0.05). The serum Adiponectin levels was significantly lower in diabetes than non-diabetics (15.74±6.70 vs. 21.52 ± 9.35) and was significantly higher in women than men (19.38 ± 7.33 vs. 12.68 ± 4.28) among diabetic and (24.63 ± 10.52 vs. 17.83 ± 6.21) among non-diabetics groups.

Conclusion: type 2 diabetes mellitus is associated with low serum adiponectin concentrations and probably adiponectin involved in the pathophysiology linking obesity to type 2 diabetes.

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Background: Autophagy is a new therapeutic strategy aimed at reducing the diabetic abnormalities. While excessive or insufficient autophagic activity during diabetes leads to altered cellular homeostasis. So, aim of the present study was conducted to determine the effect of eight-week high-intensity interval training (HIIT) along with caffeine injection on the levels of some myocardial autophagy-related proteins in diabetic rats.
Methods: In experimental design, fifty male white wistar rats with an age range of 3-2 months  (average weight 250±25 g) were randomly divided into 5 groups of homogeneous 10 rats in each group: Healthy control (C: intraperitoneal injection of saline), Diabetic control (D: high-fat diet combined with a single intraperitoneal injection of streptozotocin, Diabetic with training (D+T: running with intensity at the 85-90% of maximum speed in 5 to 12 bout of 2 min^-1; 5 days/week for 8 weeks), Diabetic with caffeine supplementation(D+CA: intraperitoneal injection of pure caffeine at 70 mg.kg^-1 5 days/week for 8 weeks), Diabetic with training and with caffeine supplementation (D+T+CA). For evaluate changes in the expression profile of some of the genes associated with autophagy signaling pathway (LC3-II, ULK-1, Beclin1) in the myocardium (left ventricular), based on Western blot analysis will be used. Also, the one-way analysis of variance (ANOVA) and Tukey post hoc test were be used to analyze the data.
Results: The expression of all autophagic proteins in diabetic with trained and non-trained groups was higher than in healthy
group (P≤0.05). On the one hand, the expression of autophagy-related proteins in the trained group with caffeine supplementation was significantly higher than that of the training group without caffeine intake (P=0.001).
Conclusion: The findings of this study suggest that caffeine injection exacerbated the expression of autophagic proteins induced by diabetes; On the other hand, high-intensity interval training can as a preventive strategy, modulate diabetes-induced myocardial autophagy.

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Background: Imbalanced production of adipokines as leptin and adiponectin in diabetic patients may lead to the development of metabolic complications. Therefore, the aim of this study was to determine the effects of 2-month of caffeine ingestion along with aerobic training on changes in serum leptin and adiponectin levels and leptin/adiponectin ratio (LAR) in type 2 diabetic men.
Methods: Thirty-two diabetic men participated in a quasi-experimental designs in the four groups for two-months period of a aerobic training (treadmill walking 3 times/week, 1.5 hour/session, 65-85% HRR) with and without caffeine ingestion (3 mg.kg^-1.day). Serum changes in leptin and adiponectin were measured during two phases (baseline and 24-hours after completing of the training program). Data were analyzed by one-way ANOVA and bonferroni's post-hoc test at level P≤0.05.
Results: Administration of two-months caffeine (CA) alone and combination with aerobic training (AT) were significantly could reduced and increased in leptin and adiponectin level, respectively (P=0.001). Thus, the combined group (AT+CA) effect were far more appropriate intervention in changing the studied indices (P=0.001). Also, the LAR method was notable reduced in all study groups, although these effects were more significantly in the combined group (AT+CA) (P=0.001).
Conclusion: It seems administration of caffeine supplementation and aerobic training for two-months have a positive effects on the improved relative of leptin and adiponectin levels as well as their ratio in diabetics, although the combination of these two variables has been shown to have far more dual effects.