مجله غدد درون ریز و متابولیسم ایران
سال پنجم شماره 4 (پیاپی 20، زمستان 1382)

Obesity is a major risk factor for type 2 diabetes, hypertension, hyperlipidemia, cardiovascular disease and certain types of cancer. Furthermore, obesity is associated with insulin resistance and hyperinsulinaemia. Hormones and cytokines such as leptin and TNF are produced by adipose tissue and have a key role in insulin resistance of obesity. The purpose of this study was to examine the effects of peripheral administration of yohimbine on some of adipose factors. Experiments were carried out on two groups of male rats: lean control group (fed standard purina rodent chow) and obese group (fed cafeteria diet). A blood sample was taken from each rat, after exposure to diet for 18 weeks. The obese group were randomly divided into two groups. Group I was injected with 4mg/kg yohimbine and group II received the equal volume of saline. Blood samples were taken 30, 60, and 120 min after drug or saline injection. Insulin level was significantly increased 30 and 60 minutes after injection (P<0.05). TNF- and leptin levels were decreased (P<0.05) while FFA level was increased in response to yohimbine, 30 minutes after injection. Glucose level was increased but it was lower than control group during 120 minutes. It has been shown previously that cAMP is the main regulatory factor of leptin, TNF- and FFA in adipocytes. In comparison to the obtained results in the control group, we conclude that probably sensitivity of – adrenergic receptors and -AR proportion are increased in obesity.

Patients with chronic renal failure have abnormal thyroid function and higher serum aluminum (Al). In recent years the toxicity of Al in human and animals has been a matter of concern. In this study the effect of high Al intake in the diet has been investigated in rats. Aluminum (1620mg/kg of the diet as aluminum chloride) was added to the diet of Wistar rats for 40 days. At the end of this period serum Al, T4 and TSH concentrations were measured. Al was determined by atomic absorption spectrometry and the hormones were assayed using commercially available kits. Serum Al concentration of the test rats (6.3±.1 μg/l) was not significantly different from controls (6.6±.4 μg/l). Serum T3 concentration in animals consuming diet with high Al content (138±8 ng/dl) was significantly lower compared to the control animals (146±7 ng/dl). Serum T4 concentration of the test animals (3.0±0.3 μg /dl) was also significantly lowers than control animals (4.7±0.5 μg/dl). Thyrotropin concentrations were not significantly different. The results of this study indicate that high Al intake in rats can disturb thyroid function and the possible adverse effect(s) of the element should be considered and fully investigated in subjects in close contact with high amounts.

Diabetes mellitus is the most common endocrine disease and diabetic retinopathy (DR) is one of its most important ophthalmic complications. It is supposed that insulin-like growth factor-1 (IGF-1) is one of the probable causative factors on formation and promotion of retinopathy. The aim of this study is to evaluate the correlation between serum total IGF-1 and IGF-binding protein-3 (IGFBP-3) levels and DR. We designed a case-control study with systematic random sampling. Sixty-three diabetic patients with no history of hypertension were examined by retinal fundoscopy, and divided into two groups (control group without retinopathy and case group with retinopathy). The serum level of fasting blood sugar (FBS) was measured by enzymatic glucose oxidase and glycosylated hemoglobin (HbA1c) by colorimetric method. Total IGF-1 and IGFBP-3 levels were measured by immunoassay. The incidence and severity of retinopathy, increased significantly with increasing age and duration of diabetes (p<0.05), but there was no correlation between retinopathy and serum levels of FBS, HbA1c, IGF-1 and IGFBP-3. There was a significant inverse correlation between age and IGF-1 in both control and case groups (p<0.05). There was a significant direct correlation between total levels of IGF-1 and IGFBP-3 in the case group (p<0.02). Our data showed that serum levels of total IGF-1 and IGFBP-3 were not correlated significantly with incidence and severity of retinopathy. However, it is postulated that with increasing sample size, the role of IGF-1 and its binding proteins as causative factors will be clear.

There is considerable experimental evidence for effects of thyroid hormones on immune system. An association between hypothyroidism and susceptibility to some infections has been also demonstrated. The aim of this study was to evaluate immunological changes in hypothyroid females. Blood samples were collected from 50 females with hypothyroidism and a control group consisting of 50 sex- and age-matched euthyroid subjects. Thyroid function was assessed according to T3, T4 and TSH levels. The following parameters were studied in the two groups: total and differential white blood cell (WBC) counts, serum concentration of immunoglobulins including IgG, IgA, IgM and IgE, CRP, C3 and C4 complement components. Decreased serum concentration of IgG and IgA was observed in hypothyroid patients compared to euthyroid females. Hypothyroid females had higher serum IgE concentration than euthyroid group (179.8 IU/ml vs. 109.8 IU/ml P<0.05). Similarly serum C3 concentration in hypothyroid patients was significantly higher as compared to euthyroid females (138.8 mg/ml vs. 117.8 mg/dl P<0.01). In euthyroid group the absolute count of circulating WBC, PMN cells and lymphocytes were slightly higher than those in hypothroid group. On the other hand, the eosinophil count was higher in hypothyroid patients as compared to control group. These results indicate that some immunological alterations occur in hypothyroid women.

Hyperalgesia is one of the symptoms of diabetic neuropathy and is considered as a major clinical complaint in these patients which could affect the quality of their life. Since attenuation of hyperalgesia is very important, in the present study the possible analgesic effect of aqueous extract of coriander was investigated in male rats with streptozotocin-induced diabetes using standard formalin test in both early (acute) and late (chronic) phases. Male albino Wistar rats (250-350 g) were used. They were randomly divided into three groups, i.e. control, diabetic and extract-treated diabetic. For induction of diabetes, streptozotocin (60 mg/Kg) was administered i.p. After one month, formalin test was conducted. Pain sensation of diabetic rats in the second interval (5-10 min) of the acute phase of the formalin test is higher (P<0.001) in comparison with control group, while a less significant difference was found between control and extract-treated diabetic group (P<0.05). On the other hand, there was no significant difference between control and extract-treated diabetic groups regarding acute and chronic phases of the formalin test. It is concluded that i.p. administration of aqueous leaf extract of coriander at a dose of 100 mg/kg does not produce a significant analgesic effect using formalin test.

Mean systolic and diastolic blood pressures and prevalence of hypertension vary throughout the world. These differences have mostly been explained by changes in diet and racial differences. However, it is believed that other factors such as calcium, vitamin D and PTH status may contribute to its pathogenesis. This study was conducted to assess the association between the serum 25-hydroxyvitamin D level and blood pressure and also between Ca, PTH and blood pressure among a group of individuals residing in Tehran. In this cross-sectional study, 251 subjects aged ≥ 40 years, 123 subjects with low vitamin D (≤ 20 ng/ml) and 128 with normal vitamin D levels(>20 ng/ml), were randomly selected from the population of the Tehran Lipid & Glucose Study (TLGS). Subject data included clinical, diet and biochemical information. Systolic blood pressure ≥ 140mm/Hg or diastolic blood pressure ≥90mm/Hg were considered as hypertension. Blood samples were taken and serum calcium, phosphorus, PTH and 25,OH vitamin D were measured. Nutritional assessment was done according to 72-hour recall and Ca and fiber intake were calculated. For each subject the energy intake to basal metabolism rate (EI:BMR) was calculated. Individuals having EI:BMR <1.35 and ≥2.4 were considered to be under-reporters and over-reporters, respectively. While comparing normotensive and hypertensive subjects for calcium intake and the correlation between blood pressure and Ca intake, under- and over-reporters were excluded. For data analysis, Student’s t test and Pearson correlation coefficient were used. In this study 136 men and 115 women aged 40-72 years (mean±SD: 50±8) were studied. Mean age, BMI, waist, FBS, TG, CHOL, LDL, Ca, P, PTH and Albumin measurements, and also fiber and calcium intake were not significantly different between the two groups with normal and low serum vitamin D levels. 57 subjects (%22.7) were hypertensive. Comparing hypertensive and normotensive subjects, no significant difference between serum Ca, PTH and vitamin D status was seen in these subjects. After excluding under- and over-reporters and adjusting for fiber, calcium intake was also not significantly different between the two groups. In this study, correlations between serum calcium and PTH with blood pressure were not significant. No significance association was found between vitamin D and systolic blood pressure, diastolic blood pressure and mean arterial blood pressure. The results of this study suggest that no significant association exists between blood pressure and the serum 25-hydroxy vitamin D, calcium, PTH and calcium intake status of subjects aged≥ 40 years.

Osteoporosis is one of the most common aging disorders. Its prevalence varies according to lifestyle and dietary habits in various countries. This study was undertaken to determine the prevalence of osteoporosis in Tehranian women aged 40-60 years in 2000. In this study, 754 non-pregnant women were selected by cluster random sampling. Sociodemographic characteristics and physical activity data were collected using a pre-tested questionnaire. Dietary data were obtained using 3 consecutive 24-hour recalls and a food frequency questionnaire of calcium-rich foods for the past week. Anthropometry and blood pressure were evaluated and BMD was measured in femur and spine. Osteoporosis was determined according to WHO definition. The prevalence of osteoporosis in spine and femur area was 15.8 and 2.9 percent, respectively and the prevalence of osteopenia was 33.8 and 26.8, respectively. 50.6 percent of women had osteoporosis or osteopenia in spine and 29.6 in femur. Bone mineral density was lower in osteoporosis or osteopenia subjects than healthy women (P<0.001). The prevalence of osteoporosis in menopause women was 4.6 percent in femur and 23.1 percent in spine area and these women had lower bone mineral density (p<0.001). Osteoporosis was also a problem in our country as other countries. It is an important problem in older adults and it is necessary to make a decision for its prevention and control.

secondary hyperparathyroidism is listed among the possible reasons for intensifying the anemia and resistance to erythropoietin therapy in hemodialysis patients. Although its exact mechanism is not entirely clarified, but shift of bone marrow cells to adipocytes, bone marrow fibrosis and decreased calciteriol can be the causes. However, the role of secondary hyperparathyroidism in severity of anemia and resistance to erythropoietin treatment in comparison to other factors like inflammation and iron deficiency is minor. In this study, we evaluated the role of secondary hyperparathyroidism in severity of anemia in hemodialysis patients. This is a descriptive-analytic study done on 36 hemodialysis patients in Hajar Hospital in Shahrekord. The study was done in 2003. CBC, calcium, phosphorus, alkaline phosphatase level, iPTH, serum iron, total iron binding capacity, transferin saturation, ferritin, and also dialysis adequacy by urea reduction rate (URR) were evaluated. All data were analyzed with SPSS software and reported as mean±SD and maximum and minimum. Correlations were analyzed by Pearson coefficient. Total patients were 36 and 55.5 % were male, 66.1 % were more than 40 years old. Mean±SD, minimum and maximum of iPTH were 439.4±433, 25 and 2234 pg/ml, respectively. Mean ± SD minimum and maximum of Hgb were 9±1.9, 6 and 14.5 g/dl and for Hct were 28.8±6.3, 20 and 52 percent. There were inverse correlations between iPTH and Htc and Hgb as well as between alkaline phosphatase and Hg and Hct (p<0.05 for all correlations). This study showed that the severity of secondary hyperparathyroidism is associated with severity of anemia. Secondary hyperparathyroidism by itself can intensify anemia of hemodialysis patients, and needs more attention to control hyperphosphatemia and parathormone hypersecretion, resulting in better treatment of anemia in hemodialysis patients.

Iodine deficiency disorders (IDD) are among the most important epidemic disorders in the world and also in our country. The surveillance of IDD may be implemented to assess the prevalence of IDD, identify high risk areas for intervention and monitor and evaluate IDD control programmes, such as salt iodization. The objective of this study was to determine total goiter rate (TGR) and urinary iodine in 6-11 year old students in Yazd province and related cities 10 years after salt iodization programme.

In this prevalence study, 4755 primary school students (2948 boys and 1807 girls) aged 6-11 were selected by multistage “probability proportionate to size” (PPS) cluster sampling in Yazd province. Thyroid examination and goiter classification were made according to WHO standard protocol by two trained physicians. Urine and household salt samples were collected from one-thirteenth of the total population. Urinary iodine was determined by digestion method. Salt iodine was determined by rapid test kit.

TGR was 40.9% in Yazd province (Girls 41.8% and boys 40.3% p>0.05). Prevalence of goiter grade 1 and grade 2 were 38.6% and 2.3%, respectively. These figures were 39.1% and 2.7% for girls and 38.3% and 2% for boys, respectively. The rate of goiter was not significantly different between two sexes (p=0.2). Overall mean of the urinary iodine in province was 264±123 μg/L and corresponding mean in girls and boys were 236±118 μg/L and 281±123 μg/L, respectively which were significantly different (p=0.001). In general, 10.5% of Yazd population had urinary iodine concentrations under 100 μg/L, 24.5% were in ideal range (100-200 μg/L) and 65% were higher than 200 μg/L. In general, 6% of household salt samples did not have iodine, 1.1% had 8ppm, 6% 15ppm and 86.8% had above 30ppm. Thus, approximately 94% of salt samples contained iodine.

The results of this study indicated that TGR, especially goiter grade 2, has markedly decreased and according to urinary iodine status, not only mean urinary iodine was elevated, but also was higher than ideal range of WHO. Thus, according to this index, it can be concluded that Yazd province has been IDD free since 2002. Keywords: Iodine deficiency, Endemic goiter, Iodine, Urinary iodine, Iodized salt, IDD, Students, Thyroid

To assess the relationship between parental consanguinity and permanent congenital hypothyroidism (PCH). From February 1998 to August 2002, cord dried blood spot samples, viz. only live births, in eight hospitals and a rural birth center in Tehran and Damavand were collected on Whatman BFC 180 filter papers. Samples with cord TSH  20 mU/L (two-site IRMA) were recalled. Between 7-14 days of life or thereafter, congenital hypothyroidism (CH) was confirmed by serum TSH > 10 mU/L and T4 < 6.5 g/dL and L-T4 was immediately started. CH-affected newborns were followed-up until May 2003. Thyroid dysgenesis was determined using 99m technetium pertechnetate thyroid scanning and/or ultrasonography. In thyroid eutopic newborns, dyshormonogenesis was diagnosed by a 4-week discontinuation of L-T4 between 2-3 years of age followed by abnormal serum TSH and T4 values. Of 35067 specimens, 373 (1.06%) were recalled, 25 had PCH (1:1403 births), 18 had thyroid dysgenesis (1:1948 births), and 7 had thyroid dyshormonogenesis (1:5010 births). Twenty-one PCH cases were detected from July 2000 onwards and 6648 (28.6%) of 23227 neonates had parental consanguinity. The odds ratio of parental consanguinity in PCH was 2.75 (95%CI: 1.17-6.47 P=0.02) and in dysgenesis was 3.74 (95%CI: 1.33-10.52 P=0.01) and the odds ratio of first-cousin parental consanguinity in PCH was 2.96 (95%CI: 1.23-7.15 P=0.02) and in dysgenesis was 3.21 (95%CI: 1.14-9.02 P=0.03) compared to non-PCH and non-dysgenetic cases, respectively. Parental consanguinity can be considered as the possible causative factor for the high prevalence of PCH and dysgenesis in Tehran.

Iron deficiency anemia is recognized as the most prevalent nutrient deficiency in the world and iron supplements, which are prescribed daily in pregnant women for prevention of this anemia, may have unfavorable effects on copper absorption. The purpose of this study was to determine the effects of iron supplementation on serum copper status of pregnant women. In a historical cohort study, from all the pregnant women in the third trimester visiting health centers, 47 pregnant women who took iron tablet (Tl) and 38 pregnant women who did not (DTI) were randomly selected. Serum copper levels were measured by colorimetery and serum iron, TIBC, and Ferritin levels were measured by spectrophotometer. The mean daily intakes of nutrients were estimated using 3-day dietary recall questionnaire and FP2 software. The data were analyzed using student’s t-test, χ2 and Pearson’s correlation coefficients. In Tl group, the mean intake of copper increased significantly compared to DTl group (P<0.05). There was a significant negative correlation between serum copper concentration and TIBC of the two groups (P<0.05). Mean iron concentration and TIBC were significantly different between the two groups (P<0.05). There was no significant difference between the mean serum copper levels of TI group when compared to the DTI group. Iron supplementation had no significant effect on serum copper status of pregnant women. The serum copper levels of 16.5 percent of pregnant women were lower than normal and another 16.5 percent were in borderline range, but the others did not have copper deficiency.Keywords:

The relationship between calcium intake during lactation and breast milk calcium concentration has been studied by many investigators, but there is no conclusive evidence on the effect of supplementation during pregnancy on the breast milk content. The aim of this double blind, placebo controlled trial was to determine the effect of calcium supplementation during the third trimester of pregnancy on the breast milk calcium concentration. Sixty-eight pregnant mothers were assigned randomly to \"Calcium Supplement\" (1 g daily, as two calcium carbonate capsules) or \"Placebo\" groups from 28th-30th week of gestation through delivery. Breast milk samples were taken 1.5-3 months after delivery. Calcium concentration was measured using atomic absorption spectrometry. Data analyses were done by SPSS (Version 9). There were no significant differences between the two groups with respect to demographic characteristics, anthropometric measures, dietary energy and calcium intakes, and blood pressure. Compliance was similar between the two groups and no participant was a smoker. Mean±SD of calcium concentrations in mature breast milk were 228±38 and 235±42 mg/L in \"Calcium Supplement\" and \"Placebo\" groups, respectively (p=0.49). Our study did not support the hypothesis stating that calcium supplementation during the third trimester of pregnancy affects concentration in mature breast milk.

In spite of many studies about the association of diet with blood pressure, yet the relationship between micronutrients and blood pressure remains obscure. This study aimed at evaluating the dietary intake of calcium, magnesium and potassium in relation to blood pressure. Trained interviewers collected dietary data on 1470 participants of Tehran Lipid and Glucose Study by means of two 24-hour dietary recalls. Energy intake (EI) to BMR ratio was calculated. Under- and over-reporters (EI: BMR<1.35 and >=2.4, respectively) were excluded from the study. Trained physicians according to standard protocols measured blood pressure. Hypertension was defined as SBP≥140 or DBP≥90 mmHg. After excluding subjects who used blood pressure-lowering drugs or vitamin-mineral supplements 94 hypertensives were included in the study. Normotensive persons, as control group, were selected randomly from subjects who were matched with hypertensives regarding age, sex, weight, BMI, energy and fiber intake. Mean ± SD of age was 42± 15 and 41± 15years for hypertensives and normotensives, respectively. Dietary intakes of calcium, magnesium and potassium were lower than RDA. Hypertensives had lower intake of calcium and potassium than normotensives (611±256 vs. 771±276 mg/d and 2461±808 vs. 2740±691 mg/d). Magnesium intake was not significantly different between the two groups. Blood pressure was decreased with calcium and potassium intake, but not with magnesium intake. The results showed an inverse correlation of calcium and potassium with blood pressure. There was no relationship between magnesium and blood pressure.

To compare the incidence of fetal, maternal and neonatal complications amongst women with gestational diabetes mellitus (GDM) and pregnant women with normal glucose tolerance in Shahrood. In order to compare fetal and maternal complications, for all pregnant women who were referred from private clinics and health care settings to Fatemiyeh Hospital for screening of GDM, prenatal care was done in a cohort study. The records of mothers and neonates were obtained from delivery and nursery units. Between GDM group (63 pregnant women) and 1247 pregnant women with normal glucose tolerance, there were significant differences (p<0.001) in the rate of hypertension in pregnancy (9.7% vs. 1.8%), still birth (6.5% vs. 0.4%), hydramnious (8.1% vs.. 0.6%), cesarean section (86.9% vs. 57.6%), and macrosomia (8.1% vs. 2.8%, p<0.05). There was no difference in the rate of pre-eclampsia, pyelonephritis, pre-term delivery, low birth weight, Intra uterine growth retardation, fetal or neonatal malformations, shoulder dystocia and need for resuscitation delivery. There was also no difference in birth weight and other neonatal birth measurements. Among Pregnant women in GDM group who were younger than 25 years and had no risk factors, there was no fetal, maternal and neonatal complications, none of them required insulin therapy in pregnancy and all had normal blood glucose after delivery. Some of the complications were higher in GDM than in normal group, possibly due to poorer glycaemic control. Moreover, according to previous studies, the prevalence of GDM in Iranian pregnant women is comparable with developed countries, so more surveys regarding selective screening and cost effectiveness of universal screening in Iranian population are recommended.