ACTA ENDOCRINOLOGICA (BUC)

Objective: The goal of this research is to investigate whether melatonin, a circadian informant, is implicated in idiopathic oligospermia in men.\r\nSubjects and methods: 12 men (mean age 30.5 yr) with normal sexual function diagnosed with idiopathic oligospermia and 8 healthy men were included. In urine 6-sulfatoxymelatonin (aMT6s), a reliable index of melatonin secretion and gonadotropins, LH and FSH were assayed. In plasma LH, FSH, DHEA-S, 17-OH progesterone, testosterone, free testosterone, SHBG were measured at 08:00.\r\nResults: As expected, in the infertile group reproductive hormones were within normal limits but persisted low testosterone and high gonadotropins. Estimated bioavailable testosterone also showed a significant decrease (p=0.03). Evaluation of individual differences in circadian production of both melatonin and gonadotropins exhibited substantial changes in their secretion pattern from the phase shifts to loss of rhythm for aMT6s. The reduced amplitudes (p=0.04) of aMT6s were associated with a longer duration of melatonin secretion (p< 0.001) as estimated from onset/offset time and a reduced ratio between night- and daytime; the mean 24h amount of aMT6s tended to decrease at significant limit (p=0.05); no significant correlation between aMT6s and gonadotropins was observed compared with the control group. The amplitudes of gonadotropins were lower while their mean 24 h amount showed a moderate increase.\r\nConclusions: The present findings suggest that the significant increase in the duration of melatonin secretion may contribute to the imbalance of reproductive hormones that affect spermatogenesis; aMT6s, urinary metabolite of melatonin may be a sensitive predictor in circadian disorders of reproductive axis.

The effects of daily evening melatonin (MT) injections on plasma T3 and T4 and pineal thyroxin 5&#8217;-deiodinase (5&#8217;-D) activity in euthyroid and hypothyroid rats were investigated. Circulating levels of thyroid hormones were monitored and 5&#8217;-D activity was measured in pineal homogenates throughout the daily light-dark cycle. In the euthyroid group, T3 and T4 concentrations and pineal 5&#8217;-D activity gradually increased during the L-phase of the L/D cycle to reach maximum levels early at night. The lowest values for pineal 5&#8217;-D activity and T4 were obtained later at night when endogenous MT production was the highest. MT treatment induced an opposite circadian variation of plasma T3, T4 and pineal 5&#8217;-D activity with significant increases later at night and decreases early at night vs. the control group. In the hypothyroid group, the serum T4 and T3 concentrations significantly decreased at all moments assayed. Treatment with MT did not lead to significant changes in the propylthiouracil effect on T4 and T3 levels, but maintained the biphasic response, observed in the MT treated euthyroid group. The increases induced by PTU in pineal 5&#8217;-D activity during the light phase, were reduced from 43.61 ? 2.35 ng T3/mg protein / h to 33.36?2.87 ngT3/mg protein/h (p=0.01) by MT injections. In conclusion, the results rendered the presence of the 5&#8217;-D in the rat pineal, its activity showing a circadian pattern similar to the circulating T4 levels. The MT treatment induced an opposite circadian variation of serum T3, T4 and pineal 5&#8217;-D activity suggesting an interaction between the light/dark cycle, 5&#8217;-D activity and responsiveness to MT.

Introduction. Vitamin D (VD) levels were correlated with different health conditions, including reproductive disorders in males. Vitamin D action is mediated through vitamin D receptor (VDR), which acts as a transcription factor. VDR gene promoter is embedded in a GC-rich island. The VDR gene has been shown to have several polymorphisms that affect the receptor function. Aim. To examine the relationship between Cdx- 2 polymorphism (rs17883968), the methylation status of VDR’s promoter and serum levels of 25-hydroxyvitamin D in male infertility. Patients and Methods. A total of 69 infertile men and 37 age-matched controls were enrolled in this study. Vitamin D level assessments were detected using the electrochemiluminescent method. Cdx-2 VDR polymorphism identification was performed by PCR on DNA samples from blood, followed by restriction. Methylation of VDR gene promoter was assessed by qMS-PCR using bisulfite-treated DNA from fresh sperm. Results. Vitamin D levels was found to be significantly decreased in infertile groups compared the controls (p=0.0279). The GG genotype was found in a higher percentage in controls and the AA genotype was higher in infertile group (p=0.0056). Infertile homozygote (GG) and heterozygote (GA) individuals had significantly higher vitamin D levels than AA homozygote. Methylation is higher in individuals with lower vitamin D levels and AA genotype is characterized by higher methylation values. Conclusion. The results provide new insights of Cdx-2 polymorphism is involved in vitamin D deficiency, highlighting the important role of epigenetic modification of vitamin D receptor and male infertility along with the genetic context.

Osteoporosis (OP) is a disease predisposing postmenopausal women to fractures, and often accompanied by insulin resistance (IR) and metabolic syndrome (MetS). Previous studies provided contradictory results concerning prevalence of MetS in postmenopausal OP. To better understand the pathogenesis of IR, we reviewed cellular and molecular aspects and systematically reviewed studies providing homeostasis model assessment (HOMA) index. Bone is an active endocrine organ maintaining its integrity by orchestrated balance between bone formation and resorption. Both osteoblasts and osteoclasts contain receptors for insulin and insulin-like growth factor-1 (IGF-1) operating in skeletal development and in the adult life. Defects in this system generate systemic IR and bone-specific IR, which in turn regulates glucose homeostasis and energy metabolism through osteocalcin. Examination of genetic syndromes of extreme IR revealed intriguing features namely high bone mineral density (BMD) or accelerated growth. Studies of moderate forms of IR in postmenopausal women reveal positive correlations between HOMA index and BMD while correlations with osteocalcin were rather negative. The relation with obesity remains complex involving regulatory factors such as leptin and adiponectin to which the contribution of potential genetic factors and in particular, the correlation with the degree of obesity or body composition should be added.

Context. Adipokines secreted by fat cells are vital to the control of energy metabolism, communicating the nutrient status with the tissues responsible for controlling both energy intake and expenditure and insulin sensitivity. Objective. We aimed to prove in an experimental animal study that maternal obesity has long term adverse fetal metabolic consequences, which pass on even to the next generation of descendants. Design. The effects of maternal obesity have been studied on animal model using 50 obese female Wistar rats, in which we induced obesity by high-calorie high-fat diet administered by gavage. Subjects and Methods. Obese rat females were sacrificed at gestation term and we analyzed the secretion of adipokines from maternal venous blood: leptin and adiponectin, placental, pancreatic, liver and brain homogenates lipid peroxidation levels estimated by: MDA (malonyl-dialdehyde), total thiols and GSH – as antioxidant factors and routine biochemistry. Results. Low levels of adiponectin and increased levels of leptin positively correlated with the value of placental and fetal tissue lipid peroxidation (from the liver, pancreas and brain) measured by elevated MDA and total thiols and low levels of GSH. The lipid peroxidation in the organs examined generated consistent results, showing high levels of peroxidation expressed through high values of MDA in the groups with Omega 6 supplements respectively no supplementation, and low levels of antioxidants expressed through glutathione and thiols. Conclusions. Endocrine secretion of adipokines from the adipocytes and the recruited macrophages of obese mothers is positively correlated with placental and tissue lipid peroxidation level and routine biochemical parameters.

Our aim was to explore the interactions of intercellular adhesion molecule (sICAM-1), TNF-&#945; (tumor necrosis factor-&#945;), interleukin-1&#945; (IL-1&#945;) and interleukin-6 (IL-6) with\r\ndopamine agonists in a culture of adenomatous cells from an nonfunctional macroadenoma.\r\nMaterials and methods. Tissue specimen from pituitary macroadenoma removed in transsphenoidal surgery was prepared for primary culture. Cells were counted and plated at 105/well into 24-well plates in a final volume of 1ml. Cabergoline in molar doses of 10-6, 10-7, 10-8, 10-9 was added and the cells were incubated for 4 days. sICAM-1, TNF-&#945;, IL-1&#945;, IL-6 were measured from cell-culture supernatants by ELISA kits.\r\nResults. sICAM-1, TNF-&#945;, IL-1&#945; and IL-6 were detected in the untreated control cultures after a 4d period. There was a negative correlation between TNF&#945; and IL-1&#945; (p=0.007).\r\nThe levels of PRL and hGH had measurable values above those found in culture medium without tumor cells. PRL positively correlated with IL-1&#945; ( p=0.05). hGH positively correlated with cell proliferation (p=0.049). Cabergoline treatment showed that IL-6 progressively decreased with the dose, ranging from -27.41% to -76.44%. TNF-&#945; significantly decreased (-65.90%; p<0.03)at the cabergoline 10-7 M dose. IL-1&#945; progressively increased with cabergoline dose, ranging\r\nfrom -2.53% to 345 %. sICAM-1 was significantly reduced by cabergoline at 10-9 (-47.12 %; p=0.045) and 10-6 M (-59.16%; p=0.01) doses. TNF-&#945; positively correlated with PRL (p=0.025); IL-6 positively correlated with hGH (p=0.044); sICAM-1 negatively correlated with hGH\r\n(p=0.009), TNF&#945; (p=0.025) and IL-1&#945; (p=0.044).\r\nConclusions. These data support the existence of an immunoendocrine network in pituitary tumorigenesis; TNF-&#945;, IL-6, IL-1&#945;, sICAM-1 significantly interfered by cabergoline\r\ntreatment in a dose-dependent way. However, future studies on different types of pituitary tumours are needed to confirm these findings.

Background. Genetic variants of the endothelial nitric oxide synthase (eNOS) gene have\r\nbeen reported to be associated with cardiovascular disease. We hypothesized that G894T\r\npolymorphism might trigger many of the endocrine-metabolic changes related to metabolic\r\nsyndrome (MetS).\r\nStudy Design. 148 subjects with MetS and 142 healthy control subjects aged 23-60 years\r\nwere studied. Fasting serum levels of insulin, cortisol, 17-OH Progesterone, DHEA,\r\nandrostendione, IGF1, GH, PRL, CRP, resistin and biochemical profile were evaluated. G894T\r\n(eNOS) polymorphism was assayed by using PCR-RFLP technique.\r\nResults. The frequencies of genotypes and alleles of G894T polymorphism did not deviate\r\nfrom the Hardy-Weinberg equilibrium. In the MetS group the percentages of both GT (51.35 vs.\r\n39.44; OR=2.09; CI=1.27-3.45; p= 0.003) and TT (16.22 vs. 8.45; OR=3.08; CI=1.41-6.74;\r\np=0.003) genotypes and T allele (41.9 vs. 28.2; OR=1.83; CI=1.3- 2.6; p=0.0005) significantly\r\nincreased compared to control group. The G894T polymorphism was more significantly\r\nassociated with the MetS in the presence of cortisol, 17-OH Progesterone, PRL, IGF1 and CRP\r\n(OR= 8.20; 95%CI=2.31-29.08; p=0.001) and significantly stronger in the presence of IGF1,\r\nPRL, 17OHP, resistin and CRP (OR= 10.21; 95%CI=2.42-43.05; p=0.002). The T allele carriers\r\nhad higher values of waist circumference, systolic and diastolic blood pressure, cortisol, 17-OHP,\r\nandrostendione, PRL, resistin and lower values of glucose, HOMA-IR in MetS group; The TT\r\ngenotype carriers had higher values of triglyceride in both control and MetS group.\r\nConclusion. Our results show an interaction between the G894T polymorphism and its\r\nphenotypes in conferring a higher susceptibility to the endocrine changes involved in\r\npathogenesis of MetS suggesting a role of the eNOS gene in the modulation of the molecular\r\nendocrine mechanisms.

-