Search results for "SEX STEROID"
showing 10 items of 16 documents
Sex hormones modulate pathogenic processes in experimental traumatic brain injury.
2018
Clinical and animal studies have revealed sex-specific differences in histopathological and neurological outcome after traumatic brain injury (TBI). The impact of perioperative administration of sex steroid inhibitors on TBI is still elusive. Here, we subjected male and female C57Bl/6N mice to the controlled cortical impact (CCI) model of TBI and applied pharmacological inhibitors of steroid hormone synthesis, that is, letrozole (LET, inhibiting estradiol synthesis by aromatase) and finasteride (FIN, inhibiting dihydrotestosterone synthesis by 5α-reductase), respectively, starting 72 h prior CCI, and continuing for a further 48 h after CCI. Initial gene expression analyses showed that andro…
Immune-Endocrine Interactions in the Fish Gonad during Infection: An Open Door to Vertical Transmission
2018
The interaction between the immune and endocrine systems has long been recognized in vertebrates. In fish, it is known that the prevalence and intensity of such infections are higher in males than in females and probably related to sex steroid hormone levels. In addition, the immune response in the fish gonad tissues is specifically regulated to prevent infertility. This condition is used by some pathogens to colonize the fish gonad, evade the systemic immune response, and so spread to the progeny. This review brings up to date our knowledge concerning fish gonad immunity and its regulation, immune-endocrine interactions, and how some pathogens use this tissue to spread to the progeny throu…
Environmental exposure to dioxins and polychlorinated biphenyls reduce levels of gonadal hormones in newborns: Results from the Duisburg cohort study
2006
Abstract Background Endocrine dysfunction related to the hypothalamic–pituitary–thyroid (HPT) and/or the hypothalamic–pituitary–gonadal axis (HPG) is being discussed as underlying developmental adversity of polychlorinated dibenzo- p -dioxins and dibenzofurans (PCDD/Fs) and polychlorinated biphenyls (PCBs). This study was done to evaluate effects related to the HPG axis. Methods A birth-cohort study was initiated in the year 2000. Healthy mother–infant pairs were recruited in the industrialized city of Duisburg, Germany. Dioxins, dioxin-like PCBs and six indicator PCBs were measured in maternal blood during pregnancy and in maternal milk. Testosterone and estradiol levels were measured in m…
Sexual dimorphism in immune function: The role of sex steroid hormones
2018
There is evidence of the relation of sex steroid hormones and sexual dimorphism in immune system response to infectious diseases. The aim of this review was to identify the role of sex hormones in immune function and sexual dimorphism of immune reactions. Gonadal hormones together with the immune system play an important role in process of immune responses to the disease [1]. Estrogens, progesterone and testosterone have different impacts on immune cells and different gonadal hormones are of high importance for responses of innate and adaptive immunity [1, 2]. Estrogens mainly enhance immune function while testosterone has a suppressive role. Higher progesterone during pregnancy leads to au…
Detection of a synthetic sex steroid in the American crocodile (Crocodylus acutus): Evidence for a novel environmental androgen
2017
Endocrine-disrupting contaminants (EDC's) are well known to alter sexual differentiation among vertebrates via estrogenic effects during development, particularly in organisms characterized by temperature-dependent sex determination. However, substances producing androgenic effects typically lack potency when tested in laboratory settings and are virtually unstudied in field settings. Here, we assay levels of a synthetic androgen, 17a-methyltestosterone (MT), in a heavily male-biased population of American crocodiles in the Tempisque River Basin of Costa Rica based on the recent hypothesis that this chemical is an EDC in developing crocodilian embryos. The presence of MT was documented in a…
Prostate cancer: from the pathophysiologic implications of some genetic risk factors to translation in personalized cancer treatments.
2013
Several pathologies affect human prostate, such as prostate cancer (PC), which is the most common non-skin malignant cancer in Western male populations. A complex interaction between genetic and environmental factors (i.e. infectious agents, dietary carcinogens) and hormonal imbalances has been reported to have a fundamental role in PC pathophysiology by evoking chronic inflammation. Thus, chronic inflammation drives prostate carcinogenesis and neoplastic progression. No adequate biomarkers exist until now to guide PC prognosis and treatment. Accordingly, the research has particularly focused its attention on genetic variants in genes, codifying molecules of signaling innate immune/inflamma…
Polychlorinated biphenyls affect histone modification pattern in early development of rats: a role for androgen receptor-dependent modulation?
2012
Background: The epigenome represents an important target of environmental pollution. Early-life exposure to polychlorinated biphenyls (PCBs) modifies sex steroid enzymes and receptor transcription patterns. Steroid receptors, such as androgen receptor (AR), function as coregulators of histone modification enzymes. Aim: To clarify if a PCB early-life exposure might affect the epigenome in rat liver, we analyzed some histone post-translational modifications (H3K4me3 and H4K16Ac) and the corresponding histone remodeling enzymes, and the AR as a histone enzyme coregulator. Results: We observed a decrease of H4K16Ac and H3K4me3 levels, possibly linked to the induction of chromatin-modifying enz…
Pineal ?synaptic? ribbons and spherules during the estrous cycle in rats
1983
In previous studies pineal "synaptic" ribbons have been shown to undergo striking numerical changes under various physiological and experimental conditions and to be regulated by beta-adrenergic mechanisms. The aim of the present investigation was to study the numbers of pineal "synaptic" ribbons and spherules in Wistar rats throughout the estrous cycle and to compare them with those in males. There were no statistically significant differences in the numbers of ribbons and spherules between males and females and in the females at the different stages of the estrous cycle, indicating that the structures in question, in vivo, do not appear to be regulated by naturally occurring changes of se…
Actions of sex hormones on the brain
1992
1. The brain is a target for sex steroid hormones. As a result of sex hormone actions on the brain various behavioral changes are observed in animal and man. This paper gives a brief overview over the multiple central nervous functions that are under modulatory control of sexual hormones and describes the complex sex steroid actions on the brain by giving an example for "activating" and "organizing" effects of estrogens on noradrenergic neurons in the brain of rats. 2. Estradiol-17 beta induced sex specific alterations in the turnover of noradrenaline in the preoptic area and mediobasal hypothalamus showing "female" or "male" responses. 3. Neonatal manipulations of female rat pups by testos…
Insight into the molecular sex dimorphism of ischaemic stroke in rat cerebral cortex: Focus on neuroglobin, sex steroids and autophagy
2020
Including sex is of paramount importance in preclinical and clinical stroke researches, and molecular studies dealing in depth with sex differences in stroke pathophysiology are needed. To gain insight into the molecular sex dimorphism of ischaemic stroke in rat cerebral cortex, male and female adult rats were subjected to transient middle cerebral artery occlusion. The expression of neuroglobin (Ngb) and other functionally related molecules involved in sex steroid signalling (oestrogen and androgen receptors), steroidogenesis (StAR, TSPO and aromatase) and autophagic activity (LC3B-II/LC3B-I ratio, UCP2 and HIF-1 alpha) was assessed in the ipsilateral ischaemic and contralateral non-ischae…