International Journal of Endocrinology and Metabolism
Volume:8 Issue: 3, sep 2010

Implication for health policy/practice/research/medical education:The diabetes mellitus as a important part of metabolic syndrome is an emerging disease and association with fatty liver is very common. Reading this editorial is recommended to all family physicians, internists, gastroenterologists, endocrinologists and health policy makers.

Diabetes Insulin Resistance Brain IGF-I In insulin-resistance animal models, insulin uptake from the periphery to the brain is impaired. Although brain insulin is not involved in glucose transfer to the neurons, it is required for neuron survival and function, mediated by binding to insulin receptors. Furthermore, an insulin homologue called insulin-like growth factor (IGF-I), which is abundantly expressed in mature neurons and acts in parallel with insulin in the brain, has the ability to bind to the insulin receptor and trigger the signal transduction pathway. Although reduced levels of brain insulin and serum IGF-I have been reported during insulin resistance, no data is available on IGF-I levels in the brain. In this study, we sought to investigate if the expression of IGF-I is also altered in brains of insulin-resistant rats. Wistar rats were given 10% fructose in their drinking water for up to 4 months to induce insulin resistance. The rats were then killed and perfused with PFA 4%; then, there brains were excised, sectioned, and examined for immunoreactivity of IGF-I. Our results showed an increased intensity of IGF-I in most brain areas of the insulin-resistant rats. Altogether, an increased expression of IGF-I in the brain could be a compensatory mechanism and substitute for low levels or lack of insulin in the brains of insulin-resistant animals.

Obesity is one of the primary risk factors of metabolic syndrome and type 2 diabetes. Considering that appropriate treatment of several metabolic syndrome disorders is a key for effectively decreasing of mortality, morbidity and disability and also because of the increasing incidence of obesity in the past century, this study was conducted to detect the incidence of abdominal obesity and its statistical relationhip with other components of the metabolic syndrome. This cross-sectional descriptive study was conducted on 1,392 type 2 diabetic patients between the ages of 30 and 83. Following laboratory and clinical evaluations and completion of questionnaires, data were statistically analyzed using Chi-square and Fisher’s exact tests for the qualitative data and t tests for the quantitative data. Among 1,392 patients with type 2 diabetes, 810 patients (58.2%) had abdominal obesity, including 46 men (5.7%) and 764 (94.3%) women. According to NCEP ATPIII1, 768 patients (94.8%) had metabolic syndrome. Significant relationships were observed between abdominal obesity and sex, hypertension, decreased HDL, and metabolic syndrome. (P < 0.01). However, no significant relationships were found between abdominal obesity and age or high TG (P < 0.01) The results of this study indicated that obesity had the strongest relationship with metabolic syndrome, indicating the necessity of its control appropriately in diabetic patients.

Obestatin is secreted from the stomach and has effects on energy balance and food intake. The purpose of the present study was to investigate obestatin, estradiol, and liver ATP responses after 8 weeks of a treadmill exercise running program at differentdurations. 37 male Wistar rats (8 to 10 weeks old, 145 to 160 g) were assigned to control (n = 9) and training (n = 28) groups. After an accommodation period of 3 weeks, the training group was further divided randomly into 30-minute (T30), 60-minute (T60), and 90-minute (T90) groups. Animals ran on a motor-driven treadmill at 20 m/min (0% grade) for various durations 5 days/week for the subsequent 5 weeks and were sacrificed 72 h after the last exercise session. Livers were excised and immediately washed in ice-cold saline and frozen in liquid nitrogen to determine liver ATP concentrations. Plasma was also collected for obestatin, glucose, and estradiol determinations. One-way analyses of variance were used for data analysis. Plasma obestatin concentrations were significantly higher after training in the T90 group compared with the T30 group. Higher and significant resting plasma estradiol levels were observed in the T60 and T90 trained rats when compared with the control group. Changes in plasma glucose and liver ATP concentrations were not significant. It seems that long-duration, high-volume training increases plasma obestatin to a greater degree than short-duration, short-volume training. The results also show that long-term exercise induced an increase in plasma obestatin and was accompanied with a higher level of estradiol.

Although transient bone loss has been described during and immediately after pregnancy and lactation, the association between breastfeeding and bone mineral density (BMD) after menopause remains controversial. To assess the association between breastfeeding and BMD in postmenopausal women in a population-based study. We randomly selected 245 healthy, free-living postmenopausal women, ages 40 to 80, from the Tehran Lipid and Glucose Study. The duration of breastfeeding was recorded. BMD was measured at the lumbar spine and upper femur by dual X-ray absorptiometry (Lunar DPXMD 7164). Multiple-linear regression was used to determine the association between the total duration of breastfeeding and BMD at different sites. Means of age and years since menopause were 57.7 ± 7 and 9.4 ± 6.8 years, respectively. The mean number of parities was 5.1 ± 2.8. The median duration of breastfeeding was 48 months (25th to 75th percentiles: 24 and 108 months). Eleven percent of the women (n = 27) were osteoporotic in the femoral-neck region and 25.3% (n = 62) were osteoporotic in lumbar-spine sites. Breastfeeding duration was correlated inversely with femoral-neck BMD, Ward’s triangle, and L2-L4. After adjusting for age, BMI, years since menopause, number of parities, 25-hydroxy vitamin D, and LnPTH in the multiple linear regression analyses, breastfeeding duration was inversely associated with BMD at the femoral neck (R2 = 0.31; P = 0.02), Ward’s triangle (R2 = 0.32; P = 0.004), and L2-L4 (R2 = 0.18; P = 0.01), but not at other sites. In healthy postmenopausal women, BMDs of the femoral neck, Ward’striangle, and the lumbar spine are inversely associated with the total duration of breastfeeding.