International Journal of Endocrinology and Metabolism
Volume:13 Issue: 4, Sep 2015

The mini-pubertal period of almost six hours in neonatal male rats is thought to be an important stage in sexual development.. The aim of this study was to investigate the effect of hormone inhibition during mini-puberty on testicular function in male rats.. We measured serum testosterone (T), luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels in male rats at different time points after birth by enzyme linked immunosorbent assay (ELISA) and established a “no mini-puberty” model by ether inhalation. The mRNA expression levels of testicular androgen receptor (AR), insulin-like growth factor 3 (INSL3), anti-Mullerian hormone (AMH), and ghrelin were determined by real-time polymerase chain reaction (PCR) assays on postnatal days 45 and 75. Testicular tissue biopsies were stained with hematoxylin and eosin (H & E) and the structure, number and maturity of testis cells (including spermatogenic, Sertoli, and Leydig cells) were observed under microscopy at the same time.. Serum T and LH levels peaked at two hours after birth, while FSH peaked at hour 0, and bilateral testicular weight peaked at four hours after birth. The rats that underwent ether inhalation five minutes after birth had markedly reduced serum hormone levels. The mini-puberty model group revealed visible morphologic alterations in the tests on postnatal day 45. Then, on postnatal day 75, the mRNA expression level of AMH significantly decreased (P < 0.05) in the same group.. The inhibition of mini-puberty period in male rats was demonstrated to have an effect on their testicular function to some extent..

Metabolic syndrome (MetS) continues to be highly prevalent and contributes to a rapidly growing problem worldwide. The most important therapeutic intervention for metabolic syndrome is diet modification, an intervention whose efficacy has been proven for metabolic syndrome.. The aim of the present study was to compare the effects of low glycemic index diet versus metformin on MetS components in adults with MetS..Patients and Fifty-one adults with MetS participated in this randomized controlled clinical trial. Patients were randomly allocated to two groups of metformin and low glycemic index diet. The intervention period was eight weeks. The studied participants were compared at baseline and the end of the trial, regarding the following factors: weight, blood pressure, waist circumference, fasting blood sugar, hemoglobin A1c and lipid profiles (Triglyceride (TG), Total Cholesterol (TC), Low-Density Lipoprotein (LDL) cholesterol, and High-Density Lipoprotein (HDL) cholesterol).. The anthropometric measurements, Fasting Blood Sugar (FBS), Hemoglobin A1c, serum lipid profiles (TG, TC, LDL-C, HDL-C) and lipoprotein ratio (LDL/HDL) showed a significant decrease after the intervention in both groups (P < 0.05). Comparison of the difference between the two groups was not significant, except for the mean reduction in FBS, which was more in the metformin group although this was not clinically significant.. This study supports the assumption that low glycemic index diet as well as metformin can positively affect metabolic syndrome components..

Random errors in the measurement of risk factors lead to bias in the exposure-disease association.. This study aimed to examine the extent of underestimation in the association of total cholesterol (TC), high density lipoprotein cholesterol (HDL-C) and triglyceride (TG) with cardiovascular disease (CVDs) in the Tehran Lipid and Glucose Study..Patients and Of 6327 eligible people in the original cohort followed for about 10 years to detect CVD events, 3063 (1224 men and 1839 women) had replicate measurements for blood lipids. Two regression dilution ratios were calculated by nonparametric and parametric methods, using replicate data from reexaminations three and six years after baseline. Adjusted and unadjusted hazard ratios (HR) were corrected for regression dilution bias.. By parametric method, based on reexamination three years after baseline, the strength of real association of usual levels of TC, TG and HDL-C with cardiovascular disease, considering β coefficients of related models, were underestimated about 42%, 51% and 81% in men and 40%, 43% and 62% in women, respectively. Underestimations were relatively independent of age, sex and body mass index. Correction for regression dilution bias led to more than 60% increase in estimated HR for TC adjusted for confounders.. Using baseline measurements of lipids led to considerable underestimation in the association of these factors with CVD outcome in TLGS. The underestimation increased with time interval between baseline and follow-up measurements for TC and TG. TC had more attenuation on estimated HR due to stronger relation with CVD risk..

Although the link between psychological distress and altered cortisol level has been already shown; very limited information exists about this association among Black youth. We tested sex differences in predictive role of symptoms of anxiety during adolescence on annual decline in morning salivary cortisol levels in early adulthood among Black youth. Patients and Data came from wave 1 (year 1994), wave 6 (year 2000), and wave 7 (year 2001) of the Flint adolescent study. In this study 176 Black youth (85 males and 91 females) were followed for 7 years from mean age of 15 at baseline to 22 at the end of follow up. Linear regression was used for data analysis with change in salivary cortisol from 2000 to 2001 as the dependent variable, symptoms of anxiety, at 1994 as independent variable, age, number of employed parents, depressive symptoms and alcohol use at 1994 as controls, and sex as the moderator. Higher level of anxiety symptoms at 1994 was predictive of a higher decline in morning salivary cortisol from 2000 to 2001 for all youths, while the effects of baseline socio-economics, depressive symptoms, and alcohol use were controlled. Among female participants, anxiety symptoms at 1994 were predictive of a greater decline in morning salivary cortisol level from 2000 to 2001. The association was not found among males. Our findings suggest sex differences in the predictive role of anxiety symptoms during adolescence on the annual decline in cortisol level during early adulthood. While most research on this topic is among White middle class individuals, our findings shed more light on the longitudinal links between psychological distress and the hypothalamus-pituitary-adrenal (HPA) axis function among Black youth. 

Compared to Whites, Blacks are exposed to higher levels of chronic stress in the United States. As a result, major BlackWhite differences exist in the baseline and response of cortisol. Yet, the potential association between baseline religiosity and subsequent cortisol levels of Blacks are not known. In the current study we aimed to determine the association between baseline religious behaviors and daytime salivary cortisol level among male and female Black youth. With a longitudinal design, data came from wave 1 (1994) and wave 6 (2000) of a cohort from an urban area in the Midwest of the United States. The study followed 227 Black adolescents (109 males and 118 females) for six years. Socio-demographics and religious behaviors (frequency of participation in religious activities) were measured at baseline. Base morning cortisol level at wave 6 was the outcome. We fitted a linear regression model to test the association between baseline religiosity at wave 1 and cortisol level at wave 6, while baseline age, socio-economics, and psychological symptoms were controlled. In the pooled sample, frequency of participation in religious activities at baseline was negatively associated with mean cortisol level at follow up (r = -0.29, P > 0.01) among all, males (r = -0.38, P > 0.01), but not females (r = -.20, P > 0.05). Frequency of participation in religious activities remained a significant predictor of subsequent cortisol level (b = -0.283, 95% CI = -.107 - -0.022) while the effect of age, socioeconomics, and psychological symptoms were controlled. We could only find such an association among male Black youth (b = -0.368, 95% CI = -0.148 - -0.024) but not female Black youth (b = -0.229, 95% CI = -.113 - 0.011). Religiosity has been used as a coping mechanism among Blacks. Religiosity may also be related to stress regulation among Black youth. Future studies need to test complex associations between race, sex, religiosity, chronic stress, coping, and function of hypothalamo-pituitary-adrenal (HPA). It is not known whether male Black youth who are and those who are not religious differently cope with stress associated with daily discrimination and living in disadvantaged neighborhoods.

Iodine is a vital component of the thyroid hormones and is required for normal growth, development, and tissue metabolism in humans and animals.. This study for the first time compares the effects of heating during pasteurization and sterilization on the iodine concentration of milk for an adequate provision of dietary iodine.. This study was carried out on multiparous Holstein Friesian lactating cows. Thirty Holstein dairy cows were fed with a diet containing 10 mg of potassium iodide (KI) per kilogram dry matter of diet. Milk samples were obtained on days 4 and 2 before and again on days 2, 4, 6, and 8 after the inclusion of KI into the total mixed ration diet of the dairy cows. The milk samples were sterilized using ultra-high temperature, following which the effect of the heating process during sterilization on the cows’ iodine concentration was compared to that in the only previous documented study from Iran in which milk supplementation with KI was the same as ours. Milk in that study was pasteurized via the high-temperature short-time method, a method which involves temperatures in excess of 73°C for durations longer than 15 seconds.. The inclusion of KI in the diet of the dairy cows in these 2 separate experiments increased their milk iodine levels. Pasteurization decreased the iodine content of the milk (P < 0.05), while no significant difference was observed in the iodine concentration of the sterilized milk.. The present study showed that the iodine concentration is not decreased during the heating process in sterilization, indicating that supplemented sterilized milk could be a good alternative vehicle for dietary iodine in the prevention of iodine deficiency..

Nonadherence to levothyroxine therapy is one cause of persistent hypothyroidism. To distinguish nonadherence from malabsorption, a levothyroxine absorption test is required. Typically, this test measures the serum free thyroxine (FT4) response to 1000 mcg of oral levothyroxine over 4 to 24 hours. Published data indicate that serum levels of FT4 are at or near their peak 2 hours after levothyroxine ingestion.. We present the successful completion of 2-hour levothyroxine absorption testing in 3 patients as a retrospective case series..Patients and Serum levels of thyroid stimulating hormone (TSH), FT4, and free triiodothyronine (FT3) were drawn at 0, 60, and 120 minutes after 1000 mcg of oral levothyroxine.. In all 3 cases, baseline thyroid function indicated the patients had taken their prescribed doses of levothyroxine prior to the absorption test. Despite high baseline levels both FT3 and FT4 increased during each absorption test, providing more evidence of adequate levothyroxine absorption. Subsequently, patients achieved normal TSH levels on lower doses of levothyroxine.. Levothyroxine absorption testing over 2 hours may offer a more rapid alternative to the commonly used longer protocols to rule out malabsorption. Scheduling a levothyroxine absorption test may induce some patients to start adhering to levothyroxine therapy..