IRANIAN JOURNAL OF ENDOCRINOLOGY AND METABOLISM (IJEM)
Year:2012 | Volume:14 | Issue:3 (SN 63)|Papers Count:16

Introduction: Diabetes mellitus is one of the most wide spread endocrine disorders and among the most important developing health issues. This disease is associated with increased free radical production and decrease in antioxidant defense systems. In this study we evaluated the effect of vitamin C supplementation on fasting and postprandial oxidative stress, inflammatory markers and lipid profiles in type 2 diabetic patients.Materials and Methods: Thirty patients with type 2 diabetes (age range 25 to 65 years) were randomly divided into two groups, 1) treatment with vitamin C (1000mg/d) and 2) the placebo group. They were supplemented for 6 weeks, after which we measured malondialdehyde, IL-6, hs-CRP and lipid profiles in fasting and postprandial state (after a breakfast containing 80g fat, the same as the first day of the study). Data analysis was carried out using Mann Whitney U test, with P<0.05 being significant by SPSS software version 11.Results: Results showed a significant decrease in fasting (p=0.006) and postprandial MDA (p<0.001) in the vitamin C group compared to controls but there were no significant changes in inflammatory markers and lipid profiles in the fasting and postprandial states.Conclusion: This study suggests that short term vitamin C supplementation can decrease fasting and postprandial oxidative stress, and thereby possibly prevent diabetes complications.

Introduction: Although some studies show that Chromium picolinate supplementation can improve glycemic control in type 2, diabetic patients, information available in this regard is conflicting. The aim of this study is to determine the effect of chromium picolinate on glycemic control in subjects with type 2 diabetes.Materials and Methods: In this the randomized, double blind placebo controlled clinical trial, 40 patients with type 2 diabetes were investigated. They were divided into two groups (n=20 each), the randomized and placebo groups, the former receiving 200 microgram chromium as chromium picolinate (n=20) for 3 months. Body composition, lipid profile, and glycemic control were determined at baseline and at the end of study.Results: Subjects randomized to chromium picolinate, as compared to the placebo group, had a significant decrease in HbA1C (-41%, P=0.007vs. 0.12%, P= 0.054) and FBS levels (-22.05%, P=0.001 vs.-1.35%, P=0.859).There was no improvement in body composition and lipid profiles of subjects randomized to chromium picolinate, compared to controls.Conclusion: Results of this study suggest that chromium picolinate supplementation in subjects with type 2 diabetes can improve glucose control but it has no effect on body composition and lipid profiles.

Introduction: Treatment of hypertension and dyslipidemia in diabetic patients significantly decreases microvascular and coronary artery diseases. Feijoa is the fruit of an evergreen tree in tropical areas which contains high amounts of polyphenols with anti oxidant, antimicrobial and anti inflammatory activity. In view of its composition we evaluated its potential for reducing cardiovascular risk factors (control of hyperglycemia, hyperlipidemia and hypertension) in patients with type 2 diabetes.Materials and Methods: Subjects were 34 men and women, 40-75 years old with type 2 diabetes, who were randomly assigned to receive either Feijoa (150 mg daily) or placebo. There were no significant differences between the 2 groups regarding age, height and body weight. Blood pressure, serum level of fasting blood sugar, total cholesterol, LDL, HDL, triglycerides, glycosylated hemoglobin, were measured and compared at the beginning and after 12 weeks.Results: Blood pressure decreased after 12 weeks in the Feijoa consumption group. Fasting blood sugar, glycosylated hemoglobin, cholesterol and triglycerides also decreased in the feijoa group in comparison to controls.Conclusion: Feijoa improves control of hyperglycemia and hyperlipidemia in diabetic patients and reduces the risk of coronary vascular diseases in patients with type 2 diabetes.

Introduction: Obesity is one of the major risk factors for cardiovascular diseases and myocardial infarction (MI). The current study aimed to compare BMI, WHR, both independently and combined, in predicting risk of MI in men.Materials and Methods: Of 5183 TLGS participants, aged over 30 years, 2206 (45.5%) were men. Mean follow up time was 6.7 years. WHR and BMI were converted to standard normal distribution and then combined and a new variable (Z score) was defined. Data analyzed by using Cox proportional hazard regression.Results: MI occurred in 53 participants during follow up. The incidence rate of MI was 390 in 100000 people. Relative risk (RR) of MI for men with BMI and WHR above the third quartile were 2.7 and 3.9 times higher than those with BMI and WHR in first quartile (P<0.01). Cox proportional hazard regression showed that WHR adjusted for age is a better index than BMI in predicting risk of MI amongst men. Combination of BMI and WHR could predict risk of MI in men with more accuracy compared to each of the BMI and WHR variables alone. Cox proportional hazard regression showed that with each increasing unit of Z score, the risk of MI increases 29%.Conclusion: A combination of WHR and BMI has higher predictability for MI risk than either WHR or BMI per se.

Introduction: Osteoporosis is a systemic disease caused by loss of Bone Mass Density (BMD) and consequent fractures of disease increase the pain and decrease the individual’s quality of life. The present study was conducted to compare the quality of life in osteoporotic postmenopausal women with their normal counterparts.Materials and Methods: A cross sectional study was conducted on 275 postmenopausal females referred to the Namazi hospital in Shiraz. BMD was measured based on WHO standards and subjects with BMD<-2.5 Standard Deviation (SD) of the average value, were defined as having osteoporosis (cases), while those with BMD>1 SD, were considered normal (controls). The Qualeffo-41 questionnaire was used to estimate the quality of life and was reported on a scale of 100. Data were analyzed by SPSS software using the t-test and descriptive statistics.Results: The mean of the quality of life score was 25.5±11.7 and based on the WHO definition, 70.2% of participants were affected by osteoporosis. Estimates for good quality of life in osteoporosis subjects and normal postmenopausal females were 22.3% and 30.5%, respectively. Comparing the different aspects of quality of life in the cases and normal postmenopausal females, showed a statistical difference between the two groups in the “social activities” aspect.Conclusion: Regarding the gradual and asymptomatic trend of osteoporosis, it is essential to pay more attention to the preventive aspect of the disease to curtail effects of its outcomes on the quality of life.

Introduction: Today the drastically rising trend of obesity is a major public health concern worldwide. Several factors such as unhealthy lifestyle and low physical fitness are related to obesity. The aim of this study thus was to investigate the association between obesity and overweight with lifestyle status and physical fitness levels in Shirazi adults.Materials and Methods: For this cross-sectional study, 727 males (n=354; mean±SD: 41.7±10.1 years of age) and females (n=373; mean±SD: 36.02±7.9 years of age) were selected via a step wise random sampling. Height and weight of the subjects were measured by standard methods and body mass index (BMI) was calculated. Subject’s lifestyle status was assessed by a self-administered questionnaire based on Breslow’s lifestyle index and physical fitness levels were determined by a physical fitness index questionnaire.Results: Prevalences of obesity and overweight in males were 13.5% and 39.5% respectively and in females were 9.3% and 36.1% respectively.Results: showed an inverse relationship between lifestyle status and physical fitness levels with overweight and obesity in both males and females (P<0.05). Despite females having a higher lifestyle index than males, both had unhealthy lifestyles.Conclusion: Unhealthy and sedentary lifestyles are effective factors in overweight and obesity in Shirazi adults, who lack healthy lifestyles.

Introduction: This study examined the effects of interval training on serum levels of leptin, cortisol, testosterone, growth hormone (GH)and insulin resistance index (HOMA-IR) in young overweight/ obese men.Materials and Methods: Eighteen previously sedentary, overweight/obese men (BMI=31.2±3.33 Kg/m2, mean age 20 y-3 mo) in two, the experimental and control groups, participated in 16 weeks of moderate to high intensity interval training (8-10´ 4 minutes sets of running at 60-90% of Reserve Heart Rate and 2 minutes rest interval at 40-50% of Reserve Heart Rate), three days per week. Serum levels of leptin, cortisol, testosterone, insulin, GH and HOMA-IR, and anthropometric indices were measured before and 48 hours after the last training session. Statistical analysis was done by paired and independent t-test and Pearson correlation, P value<0.05 being considered significant.Results: Interval training resulted in decreased in levels of leptin (P=0.007) and anthropometric indices such as body fat percent, body fat mass, waist circumference and waist- to- hip ratio (P<0.05); testosterone and cortisol levels increased following interval training (P<0.05). However, no significant correlation was found between primary levels and alterations in leptin levels and the anthropometric indices assessed (P>0.05).Conclusion: Moderate to high intensity interval training improves lipid metabolism via regulating leptin, testosterone and cortisol levels and body composition, in young overweight/obese men, changes that may not be in line with changes occuring in insulin and GH.

Introduction: This study examined the effects of circuit resistance exercise on fat and carbohydrate metabolism during endurance exercise in overweight men.Materials and Methods: Ten overweight men (mean±SD: age, 28.8±4.8 yr; BMI, 28.2±1.4 kg/m2; vo2max, 23.3±3.7 ml/kg/min) performed two types of exercise regimens: 1) Endurance exercise (E), and 2) Circuit resistance exercise, followed by endurance exercise (RE). Circuit resistance exercise consisted of six stations, each with three circuits at 50% of 1-RM (one repetition maximum), and a total exercise time of 21 min. Endurance exercise consisted cycle ergometer exercise at 60% of the maximal oxygen uptake for 30 min. Expired gases at rest, before and during endurance exercise were measured for calculating fat and carbohydrate oxidation. Venous blood samples were taken at rest, before and immediately after endurance exercise. Blood samples were analyzed for glucose, nonestrified fatty acids (NEFA), malonyl COA (MCOA), glycerol and insulin.Results: Plasma glycerol concentrations during endurance exercise increased 53% in RE vs. 46% in the E group (P<0.001). Concentration of plasma glucose before endurance exercise was higher in RE than in the E group (P<0.001). In RE exercise, although fat oxidation through the 30-min endurance exercise (mean value) was greater than in the E regimen, there was no significant difference between the two groups (P>0.05). Also, no significant difference was observed in the NEFA, MCOA, insulin, carbohydrate oxidation responses (P>0.05).Conclusion: Lipolysis during the submaximal exercise is enhanced by prior circuit resistance exercise in overweight men.

Introduction: The purpose of this cross-over study was to investigate of hormonal responses to two programs of exhaustive resistance training with different intensities in male body builders.Material and Methods: Participants were 13 men(age 23.8±5.53 years, height 177.53±5.69 cm, body weight 76.13±8.91 kg, waist to hip ratio 0.85±0.33) who had regular resistance training at least 3 times a week for more than 3 months. Study design was crossover. Subjects participated in three states of control, moderate resistance exercise (with 65% intensity, one repetition maximum) and high resistance exercise (90% intensity, one repetition maximum) modes, in 5 sessions. Blood samples were taken before exercise in fasting state, immediately after and one hour after exercise protocol. The data were analyzed using the analyses of variance method (ANOVA) with repeated measures and multiple analyses variance (MANOVA).Results: After adjusting the results relative to plasma volume changes, no significant differences were observed between the three groups in hormonal responses of testosterone, cortisol, growth, insulin, epinephrine and norepinephrine at the time points of immediately after and one hour after exercise protocol.Conclusion: It can be concluded that resistance exercise until exhaustion with moderate and high intensity, does not induce significant changes in acute and chronic responses of circulating anabolic and catabolic hormones in male body builders.

Introduction: Haploytpes are important elements in study of genetic associations. The haplotype based association test (HBAT) is a method to study genetic association of haplotypes with one or more traits. The test statistic in this method, which is calculated for all haplotypes, follows a standard normal distribution. In this study, in order to find the chromosomal area locus of genes affecting metabolic syndromes, the HBAT method was used to investigate the genetic association of haplotypes of some candidate microsatellites with HDL-C, triglycerides, and waist.Materials and Methods: A sum of 125 families with at least one member having metabolic syndrome according to ATPIII, and at least two members with low HDL-C levels were selected from among participants of the Tehran Lipid and Glucose Study (TLGS). The genetic association of HDL-C, triglycerides, and waist with haplotypes of some microsatellites of chromosome 8, 11, 12, and 16 was studied, using HBAT.Results: Data was obtained for 125 families, consisting of 563 individuals, aged 20 years or above (269 males and 294 females). Genetic association of the haplotype 2-2-2-2 of chromosome 8 showed significant association with HDL-C and triglycerides. Haplotypes 2-2-1 and 2-2-2 of chromosome 12 showed significant association with triglycerides. In addition, haplotype 1-1-2 of this chromosome was found to be associated with waist (P<0.05).Conclusion: Researching haplotypes provides more information on genetic associations, and identification of haplotypes influencing HDL-C level, triglycerides, and waist may be helpful in designing future research aimed at determining the genes predisposing persons to metabolic syndrome.

Introduction: Orexin is a potent orexigenic agent in rodents and humans. Some research shows that orexin participates in the adaptive response to weight loss and its levels rise with dieting. On the other hand, weight loss and fasting is accompanied by increased levels of epinephrine and cortisol. In this study we investigated the effects of epinephrine (EN) and cortisol on fastinginduced orexin secretion in rats fed different levels of their energy requirements.Materials and Methods: Forty-five male wistar rats (300-350 g, 15 per group) were fed a diet containing 100%, 50% and 25% of their energy requirement for 10 days, rats were anesthetized following 48 hour prolonged fasting and then cannulated in the carotid artery for drug injection and blood sampling. Animals were divided into 3 treatment groups that received either (3 mg/Kg BW) EN, cortisol or a combination of those two (0.1 mg in 1 ml of PBS). Orexin and glucose levels were analyzed before (time 0), and 30, 60 and 120 min after injection.Results: In the 50% and 100% food restricted groups, fasting orexin levels fell after EN and the combination of EN and cortisol injection respectively (p£0.05). In contrast, the group that had 25% food restriction showed no response to cortisol, EN or the combination of both (p>0.05).Conclusion: These results indicate that injection of EN suppresses starvation-induced secretion of orexin in normal (100%) and starved (50%) rats, and that orexin secretion response to EN might be affected by weight loss.

Introduction: Several factors such as dopamine affect food intake and appetite. Release of dopamine from dopaminergic neurons is associated with ascorbic acid (AA). The nucleus accumbens via direct and indirect anatomical connections with the lateral hypothalamus is effective in control of feeding behavior. Based on these observations, the aim of the present study was to investigate the effect of central injection of ascorbic acid into the nucleus accumbens shell on the food intake and body weight of adult male rats.Materials and Methods: Thirty five adult male rats were divided into five groups as follows (n=7 each): Control, sham (injected vehicle of AA), and Ascorbic Acid (AA) groups (10, 50, and 250 1mg/rat). Rats were anaesthetized and cannulas were implanted bilaterally in the nucleus accumbens shell (AP=1.7 mm, LA=±0.8 mm from bregma, DV=5.6 mm from skull surface). After one week recovery period, three different doses of ascorbic acid (1 ml/day) were injected into the three separate groups for 4 days. Food intakes were measured every 24 hours and weight changes were determined after 4 days.Results: Doses of ascorbic acid (10, 50, and 250 1mg/rat) decreased food intake significantly (p<0.01). Although the partial decrease was observed in the body weight, but the decrease was not significant in any of the different doses groups.Conclusion: Based on our results, it seems that ascorbic acid in the nucleus accumbens shell, probably via hunger and the satiety control centers in the hypothalamus, regulates body weight and food intake.