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Sex has a role in the incidence and outcome of neurological illnesses, also influencing the response to treatments. Neuroinflammation is involved in the onset and progression of several neurological diseases, and the fact that estrogens have anti-inflammatory activity suggests that these hormones may be a determinant in the sex-dependent manifestation of brain pathologies. We describe significant differences in the transcriptome of adult male and female microglia, possibly originating from perinatal exposure to sex steroids. Microglia isolated from adult brains maintain the sex-specific features when put in culture or transplanted in the brain of the opposite sex. Female microglia are neuroprotective because they restrict the damage caused by acute focal cerebral ischemia. This study therefore provides insight into a distinct perspective on the mechanisms underscoring a sexual bias in the susceptibility to brain diseases.

Inflammatory activation of microglia is a hallmark of several disorders of the central nervous system. In addition to protecting the brain against inflammatory insults, microglia are neuroprotective and play a significant role in maintaining neuronal connectivity, but the prolongation of an inflammatory status may limit the beneficial functions of these immune cells. The finding that estrogen receptors are present in monocyte-derived cells and that estrogens prevent and control the inflammatory response raise the question of the role that this sex steroid plays in the manifestation and progression of pathologies that have a clear sex difference in prevalence, such as multiple sclerosis, Parkinson's disease, and Alzheimer's disease. The present review aims to provide a critical review of the current literature on the actions of estrogen in microglia and on the involvement of estrogen receptors in the manifestation of selected neurological disorders. This current understanding highlights a research area that should be expanded to identify appropriate replacement therapies to slow the progression of such diseases.

Lipoprotein synthesis is controlled by estrogens, but the exact mechanisms underpinning this regulation and the role of the hepatic estrogen receptor α (ERα) in cholesterol physiology are unclear. Utilizing a mouse model involving selective ablation of ERα in the liver, we demonstrate that hepatic ERα couples lipid metabolism to the reproductive cycle. We show that this receptor regulates the synthesis of cholesterol transport proteins, enzymes for lipoprotein remodeling, and receptors for cholesterol uptake. Additionally, ERα is indispensable during proestrus for the generation of high-density lipoproteins efficient in eliciting cholesterol efflux from macrophages. We propose that a specific interaction with liver X receptor α (LXRα) mediates the broad effects of ERα on the hepatic lipid metabolism.

Metabolic and reproductive pathways are tightly associated, and this relationship has been conserved throughout evolutionReproductive disorders can lead to changes in metabolic functionSimilarly, metabolic disorders can underlie changes in reproductive functionHormone replacement therapy for reproductive disorders might also have beneficial effects on energy metabolism

The activity of the nuclear factor-Y (NF-Y) transcription factor is restricted to proliferating cells in vitro. We engineered transgenic mice that enabled bioluminescence imaging of NF-Y activity in every area of the body. We visualized areas of proliferation, and we highlight for the first time a role of NF-Y activity in hepatocyte proliferation during liver regeneration.

Background.In September 2008, under the French Presidency of the European Union and with the support of the Polish Minister of Health, a European Summit on Age-Related Disease was organised in Wroclaw (Poland). At this meeting, European politicians, gerontologists and geriatricians gathered to discuss a common approach to future challenges related to age-related disease. Politicians and decision-makers from the European Union and Ministers of Health and their deputies from many European countries raised the problems and difficulties to be tackled in a growing population with a high burden of disease, and asked scientists to write a consensus document with recommendations for future actions and decisions. Scientists and clinicians worked in parallel in three different groups, on health promotion and preventive actions, basic research in age-related disease, and clinical aspects of disease in older people. Beforehand, the format of the paper with recommendations was discussed, and it was finally agreed that, for a better understanding by decision-makers, it would be divided in two different columns: one with facts that were considered settled and agreed by most experts (under the heading We know), and a second with recommendations related to each fact (We recommend). No limit on the number of topics to be discussed was settled. After careful and detailed discussion in each group, which in most cases included the exact wording of each statement, chairpersons presented the results in a plenary session, and new input from all participants was received, until each of the statements and recommendations were accepted by a large majority. Areas with no consensus were excluded from the document. Immediately after the Summit, the chairpersons sent the document both to the main authors and to a list of experts (see footnote) who had made presentations at the summit and agreed to review and critically comment on the final document, which is presented below. As regards the scientific aspects of the planning of the Summit, several organisations, under the leadership of the EUGMS, were asked both to review the program and to suggest names of speakers and participants. After the Summit, the Boards of these organizations (European Union Geriatric Medicine Society (EUGMS), International Association of Gerontology and Geriatrics-European Region (IAGG-ER), European Association of Geriatric Psychiatry (EAGP), International Society of Gerontechnology (ISG) and International Society for the Study of the Aging Male (IS-SAM) agreed to consider the document as an official paper, and help with its dissemination. The name Silver Paper was used, recalling the grey or silvery hair of our older citizens, as an easy reference. It has been sent officially to several bodies of the European Union and to Health Ministers of most European countries; and will be published in other languages in local purnals. Its declared intention is to foster changes in policies which may, in the future, reduce the burden of disease in old age.

New 17β-estradiol (E2) derivatives 1−11were synthesized from an estrone derivative by addition of organometallic reagents prepared from protected α,ω-alkynols and further elaboration of the addition products. The estrogenic activity of these novel compounds was determined using in vitrobinding competition assay and transactivation analysis. Among the E2derivatives synthesized, compound 2showed the highest transactivation potency and was therefore tested for its ability to modulate cutaneous wound healing in vivo.Compound 2’s ability to accelerate wound healing in ovariectomized mice and decrease the production of inflammatory molecules was comparable to that of E2. However, the activity of compound 2was not superimposable to E2with regard to the cells involved in the wound repairing process. When locally administered, compound 2did not show any systemic activity on ER. This class of compounds with clear beneficial effects on wound healing and suitable for topical administration may lead to the generation of innovative drugs for an area of unmet clinical need.

Estrogen is known to affect vascular function and diabetes development, but the relative contribution of estrogen receptor (ER) isoforms is unclear. The aim of this study was to determine how individual ER isoforms modulate inflammatory enzymes in the vascular wall of control and streptozotocin (STZ)-injected rodents. Primary cultures of rat aortic smooth muscle cells (SMCs) were stimulated with inflammatory agents in the presence or absence of increasing concentrations of the ERα and ERβ-selective agonists 4,4′,4′′-(4-propyl-[1 H]-pyrazole-1,3,5-triyl)trisphenol (PPT) and diarylpropionitrile (DPN), respectively. The production of inducible nitric-oxide synthase (iNOS), a classical indicator of vascular inflammation, was significantly reduced by PPT in control but not diabetic SMCs, whereas it was further enhanced by DPN treatment in both groups. This distinct action profile was not related to changes in ER transcriptional activity. However, extracellular signal-regulated kinase 1/2 signaling was activated by DPN but not by PPT in cytokine-treated SMCs. In cultured aortic rings from both normoglycemic and STZ-diabetic mice, pharmacological activation of ERα attenuated cytokine-driven iNOS induction by 30 to 50%. Vascular iNOS levels were decreased consistently when adding 1 nM 17β-estradiol to aortic tissues from ERβ- but not ERα-knockout mice. These findings suggest a possible role for ERα-selective ligands in reducing vascular inflammatory responses under normo- and hyperglycemic conditions.

Estrogen is known to affect vascular function and diabetes development, but the relative contribution of estrogen receptor (ER) isoforms is unclear. The aim of this study was to determine how individual ER isoforms modulate inflammatory enzymes in the vascular wall of control and streptozotocin (STZ)-injected rodents. Primary cultures of rat aortic smooth muscle cells (SMCs) were stimulated with inflammatory agents in the presence or absence of increasing concentrations of the ER alpha and ER beta-selective agonists 4,4',4''-(4-propyl-[1H]-pyrazole-1,3,5-triyl)trisphenol (PPT) and diarylpropionitrile (DPN), respectively. The production of inducible nitric-oxide synthase (iNOS), a classical indicator of vascular inflammation, was significantly reduced by PPT in control but not diabetic SMCs, whereas it was further enhanced by DPN treatment in both groups. This distinct action profile was not related to changes in ER transcriptional activity. However, extracellular signal-regulated kinase 1/2 signaling was activated by DPN but not by PPT in cytokine-treated SMCs. In cultured aortic rings from both normoglycemic and STZ-diabetic mice, pharmacological activation of ER alpha attenuated cytokine-driven iNOS induction by 30 to 50%. Vascular iNOS levels were decreased consistently when adding 1 nM 17beta-estradiol to aortic tissues from ER beta- but not ER alpha-knockout mice. These findings suggest a possible role for ER alpha-selective ligands in reducing vascular inflammatory responses under normo- and hyperglycemic conditions.

We report here the finding of a new pharmacological activity of a well known antagonist of peroxisome proliferator-activated receptors (PPARs). PPARs belong to the family of nuclear receptors playing a relevant role in mammalian physiology and are currently believed to represent a major target for the development of innovative drugs for metabolic and inflammatory diseases. In the present study, the application of reporter animal technology was instrumental to obtain the global pharmacological profiling indispensable to unraveling 3-(1-(4-chlorobenzyl)-3-t-butylthio-5-isopropylindol-2-yl)-2,2-dimethylpropanoic acid (MK-886)-selective PPAR modulator (SPPARM) activity not underlined by previous traditional, cell-based studies. The results of this study, demonstrating the usefulness of reporter mice, may open new avenues for the development of innovative drugs for cardiovascular, endocrine, neural, and skeletal systems characterized by limited side effects.

The glucocorticoid receptor (GR) and estrogen receptor (ER) play important roles in both physiological and pathological conditions involving cell growth and differentiation, lipolysis, control of glucose metabolism, immunity, and inflammation. In fact, recent studies suggest that 17β-estradiol, like glucocorticoids, may also have anti-inflammatory properties, even if the molecular mechanisms responsible for these activities have not yet been completely clarified. The present study was designed to gain a better understanding of the possible cross-talk between GR and ER in a model of lung inflammation (carrageenan-induced pleurisy). In particular, we have investigated whether fulvestrant (ICI 182,780), a selective ER-α antagonist, is able to attenuate the well known anti-inflammatory effect of dexamethasone (DEX), a synthetic glucocorticoid, in ovariectomized rats. We show that ICI 182,780, a selective ER-α antagonist, reverses the anti-inflammatory activity exhibited by DEX. Moreover, the coadministration of ICI 182,780 significantly inhibited the ability of DEX to reduce: 1) the degree of lung injury, 2) the rise in myeloperoxidase activity, 3) the increase of poly-(ADP-ribose) polymerase activity, tumor necrosis factor α, and interleukin-1β levels, 4) inducible nitric-oxide synthase, 5) lipid peroxidation, 6) nitrotyrosine formation, 7) cyclooxygenase expression, and 8) the IκB-α degradation caused by carrageenan administration. In addition, quantitative PCR shows that DEX down-regulates GR and up-regulates glucocorticoid-induced leucine zipper levels, whereas ICI 182,780 does not counteract these effects. In conclusion, these results suggest that the in vivo anti-inflammatory property of DEX is also related to the ER-α.

In the uterus insulin-like growth factor-1 (IGF-1) signaling can be initiated by estradiol acting through its nuclear receptor (estrogen receptor (ER)) to stimulate the local synthesis of IGF-1. Conversely, in vitrostudies have demonstrated that estradiol-independent ER transcriptional activity can be induced by IGF-1 signaling, providing evidence for a cross-talk mechanism between IGF-1 and ER. To investigate whether ERα is required for uterine responses to IGF-1 in vivo, both wild-type (WT) and ERα knockout (αERKO) mice were administered IGF-1, and various uterine responses to IGF-1 were compared. In both WT and αERKO mice, IGF-1 treatment resulted in phosphorylation of uterine IGF-1 receptor (IGF-1R) and formation of an IGF-1R/insulin receptor substrate-1/ phosphatidylinositol 3-kinase signaling complex. In addition, IGF-1 stimulated phosphorylation of uterine Akt and MAPK in both WT and αERKO mice. However, IGF-1 treatment stimulated BrdUrd incorporation and proliferating cell nuclear antigen expression in WT uteri only. To determine whether ERα can be activated in vivoby IGF-1 signaling, transgenic mice carrying a luciferase gene driven by two estrogen response elements (ERE-luciferase mice) were utilized. Treatment of ovariectomized ERE-luciferase mice with IGF-1 resulted in an increase in uterine luciferase activity that was attenuated in the presence of the ER antagonist ICI 182,780. Together these data demonstrate that 1) functional signaling proximal to IGF-1R is maintained in the αERKO mouse uterus, 2) ERα is necessary for IGF-1 induction of uterine nuclear proliferative responses, and 3) cross-talk between IGF-1R and ER signaling pathways exists in vivo.

Background: We have recently demonstrated that 17β-estradiol (E2) inhibits the increase of inducible nitric oxide synthetase (iNOS) activity in selected model systems such as macrophages, microglia, smooth muscle cells, and proposed that this effect might be associated with an antiinflammatory activity of this hormone. Here we investigate the effects of endogenous estrogens in rats subjected to carrageenan-induced pleurisy. Materials and Methods: Adult female rats were ovariectomized 3 weeks before the experiments to deplete circulating estrogens. Selected inflammatory markers, landmarks of the delayed phase of carrageenan-induced pleurisy, were measured in intact (N-OVX), and ovariectomized (OVX) female rats. In addition, the effect of hormone replacement was evaluated in ovariectomized rats with intraperitoneal injection of 17β-estradiol (E2; 50 µg/kg) 1 hr before carrageenan treatment (OVX + E2). Results: Ovariectomy enhanced the carrageenan-induced degree of pleural exudation and polymorphonuclear leukocyte migration in rats subjected to carrageenan-induced pleurisy. Lung myeloperoxidase (MPO) activity and lipid peroxidation were significantly increased in estrogens-deprived rats. The iNOS in lung samples was significantly increased by the surgery. The increase of iNOS activity was correlated with a marked enhancement in the production of TNF-αand IL-1β. Immunohistochemical analysis for P-selectin and ICAM-I, as well as nitrotyrosine and poly (ADP-ribose) synthetase (PARS) revealed a positive staining in lungs from carrageenantreated rats, which was markedly enhanced in ovariectomized rats when compared to cycling rats, particularly in the estrous phase of the cycle. Estrogen replacement counteracted the effect of surgery on all of the above indicators of lung inflammation, suggesting that in the cycling rat this hormone plays a key role in the increased sensitivity to inflammatory injury observed in the OVX rat. Conclusion: This study demonstrates that endogenous estrogens production plays an important protective role against carrageenan-induced acute inflammation by decreasing the expression of specific markers of the delayed phase of this well-known model of acute inflammation.

The present study stems from previous observations demonstrating that in the neuroblastoma cell line SK-ER3 the mRNA content of the pro-apoptotic gene Nip2 is decreased following treatment with estradiol. We investigate the content of Nip2 mRNA during the maturation of rat embryo brain and we show that Nip2 mRNA is very low at embryo day 15 and steadily increases up to day 20. At day 21 Nip2 mRNA is decreased almost to the low levels observed in the mature brain. Studies in neurons from rat embryo at day 18 show that Nip2 mRNA content is significantly decreased by exposure to estradiol at 1 nM concentration demonstrating that the observations previously done in the SK-ER3 neuroblastoma cell line can be reproduced in neurons in culture. The finding that estrogens may modulate the activity of Nip2 gene activity may be of relevance not only with regard to the effects of estradiol on brain maturation, but also for the understanding of the neuroprotective effects recently described for this hormone.

The number of studies illuminating major sex differences in liver metabolic activities is growing, but we still lack a theory to explain the origin of the functional differences we are identifying. In the animal kingdom, energy metabolism is tightly associated with reproduction; conceivably, the major evolutionary step that occurred about 200 million years ago with placentation determined a significant change in female physiology, as females had to create new energy strategies to allow the growth of the embryo in the womb and the lactation of the newborn. In vertebrates the liver is the metabolic organ most tuned to gonadal functions because the liver synthesizes and transports of all the components necessary for the maturation of the egg upon estrogenic stimulation. Thus, in mammals, evolution must have worked on the already strict gonad-liver relationship fostering these novel reproductive needs. As a consequence, the functions of mammalian liver in females diverged from that in males to acquire the flexibility necessary to tailor metabolism according to reproductive status and to ensure the parsimonious exploitation and storage of energy for the continuation of gestation in case of food scarcity. Indeed, several studies show that male and female livers adopt very different strategies when confronted with nutritional stress of varied origins. Considering the role of liver and energy metabolism in most pathologies, a better focus on liver functions in the 2 sexes might be of considerable help in personalizing medicine and pharmacology for male and female needs.

Induction of apoptosis of mononucleated cells is a physiological process for regulating the intensity of the immune response. The female steroid hormones estrogen (E2) and progesterone (Prog) are known to modulate the reactivity of the immune system; recently it has been demonstrated that they can regulate induction of apoptosis of endothelial cells and osteoblasts. TNF‐α‐mediated induction of apoptosis has been well characterized in myeloid cells. We investigated whether E2and Prog could interfere with TNF‐α‐induced apoptosis of the monoblastoid U937 cell line. Treatment with E2or Prog increased survival and prevented apoptosis induced by TNF‐α in both undifferentiated and macrophage‐like PMA‐differentiated U937 cells, as assessed by trypan blue exclusion cell counting, thymidine incorporation, AnnexinV labeling, followed by flow cytometry and DNA fragmentation studies. This effect can be associated with the activation of specific hormone receptors, since we observed the expression of the estrogen receptor α (ER‐α), ER‐β, and progesterone receptor (PR) mRNAs; the ER‐α protein expression was confirmed by immunocytochemical analysis. In addition, hormone‐mediated survival against apoptosis was concentration dependent, reaching the half‐maximal effect at 10 nM and blocked by the ER antagonist ICI 182,780 in undifferentiated cells, further supporting a receptor‐mediated mechanism of cell survival. Other steroid receptor drugs such as Raloxifene, RU486, or the ICI 182,780 in PMA‐differentiated cells displayed agonist activity by preventing TNF‐α‐induced apoptosis as efficiently as the hormones alone, providing further evidence to the notion that steroid receptor drugs may manifest agonist or antagonist activities depending on the cellular context in which they are studied. Treatment with E2was also associated with a time‐dependent decrease in the mRNA level of the proapoptotic Nip‐2 protein, supporting the hypothesis that hormone responsiveness of U937 cells is mediated by target gene transcription. Together, these results demonstrate that ER and PR can be activated by endogenous or exogenous ligands to induce a genetic response that impairs TNF‐α‐induced apoptosis in U937 cells. The data presented here suggest that the female steroid receptors play a role in regulation of the immune response by preventing apoptosis of monoblastoid cells; this effect might have important consequences in the clinical use of steroid receptor drugs.—Vegeto, E., Pollio, G., Pellicciari, C., Maggi, A. Estrogen and progesterone induction of survival of monoblastoid cells undergoing TNF‐α‐inuced apoptosis. FASEB J.13, 793–803 (1999)

SK-ER3 cells were recently demonstrated to represent a valuable model for the study of estrogen-inducible differentiation of neural cells in culture. This system may constitute an important tool also for the analysis of the effects of neurotoxic drugs. The present study demonstrates that short term exposure to Mn causes increased proliferation rate of SK-ER3 cells regardless of their differentiation. Long term treatment causes cell death in undifferentiated cells at concentrations of the metal as low as 100 nM. When the cells are differentiated with estrogens, death is observed only with a Mn concentration two orders of magnitude higher. Measurement of neurite extension and quantitation of tyrosine hydroxylase content after long-term exposure to the metal allow the conclusion that Mn does not alter the state of differentiation of SK-ER3 cells induced by the treatment with the hormone. The study underlines the importance of studying the effect of Mn in proliferating neural cells and demonstrates the toxic role of micromolar concentrations of the metal in fully differentiated neural cells. Since other authors produced evidence of effects of the metal on cell death and proliferation only at millimolar concentrations, and none described its proliferative activity, the model utilized in the present study seems to be of particular interest.

Our data indicate that estrogens and progesterone can regulate the number of GABA receptors (as detected by [3H]muscimol binding assay) in rat brain. Both hormones act in selected areas. The extent of the effect (up to 160% increase) and the number of areas responsive suggest that sex hormones may play a very important role in the regulation of the functions of GABAergic transmission in the central nervous system.

The influence of dexamethasone on monoamine oxidase (MAO) A and B expression and activity was investigated in primary cultures of rat type 1 astrocytes cultured under serum free, defined conditions. Dexamethasone treatment resulted in a dose- and time-dependent induction of MAO-B, but not of MAO-A, activity. The selective MAO-B increase was substantially reduced by the antagonist RU 486, thus suggesting a glucocorticoid receptor-mediated action of the hormone. Kinetic analysis showed an increase inVmax of MAO-B with no change in apparentKm. The dexamethasone-induced selective rise in MAO-B activity appeared to be due to enhanced enzyme synthesis, since MAO-B mRNA was markedly increased by dexamethasone treatment and the recovery of MAO-B activity after its irreversible inhibition by deprenyl was more pronounced in the presence than in the absence of the hormone. Furthermore, the dexamethasone effect was abolished by the protein synthesis inhibitors actinomycin D or cycloheximide. The present study demonstrates that dexamethasone is able to selectively induce MAO-B in type 1 astrocytes and leads to speculation of a possible role for glucocorticoids in the increase in brain MAO-B associated with neurodegenerative disorders, such as Parkinson's and Alzheimer's diseases.

Neurodegenerative diseases (NDs) are a wide class of disorders of the central nervous system (CNS) with unknown etiology. Several factors were hypothesized to be involved in the pathogenesis of these diseases, including genetic and environmental factors. Many of these diseases show a sex prevalence and sex steroids were shown to have a role in the progression of specific forms of neurodegeneration. Estrogens were reported to be neuroprotective through their action on cognate nuclear and membrane receptors, while adverse effects of male hormones have been described on neuronal cells, although some data also suggest neuroprotective activities. The response of the CNS to sex steroids is a complex and integrated process that depends on (i) the type and amount of the cognate steroid receptor and (ii) the target cell type-either neurons, glia, or microglia. Moreover, the levels of sex steroids in the CNS fluctuate due to gonadal activities and to local metabolism and synthesis. Importantly, biochemical processes involved in the pathogenesis of NDs are increasingly being recognized as different between the two sexes and as influenced by sex steroids. The aim of this review is to present current state-of-the-art understanding on the potential role of sex steroids and their receptors on the onset and progression of major neurodegenerative disorders, namely, Alzheimer's disease, Parkinson's diseases, amyotrophic lateral sclerosis, and the peculiar motoneuron disease spinal and bulbar muscular atrophy, in which hormonal therapy is potentially useful as disease modifier.

Accumulating evidence shows that estrogens are protective factors in inflammatory lung diseases and are related with the gender-related incidence of these pathologies. The aim of this study was to identify which estrogen receptor (ER), ER-α and/or ERβ, mediates hormone antiinflammatory effects in lung and how gender or aging modify this effect. Acute lung inflammation in wild type, ERα or ERβ knockout animals was induced by pleural injection of carrageenan; female mice were used and sham operated, ovariectomized, or ovariectomized and treated with 17β-estradiol (E2) before carrageenan. Our data show that ERα, and not ERβ, mediates E2-induced reduction of the inflammatory response. By real-time PCR and immunohistochemistry assays, we demonstrate ERα expression in the resident and migrating inflammatory cells of the lung, in which ERβ could not be detected. In these cells, E2-mediated reduction in the expression of inflammatory mediators was also due to ERα. In parallel, we observed that female mice were more prone to inflammation as compared with males, suggesting a gender-related difference in lung susceptibility to inflammatory stimuli, whereas the effect of E2was similar in the two sexes. Interestingly, aging results in a strong increase in the inflammatory response in both sexes and in the disruption E2/ERα signaling pathway. In conclusion, our data reveal that E2is able to regulate lung inflammation in a gender-unrelated, age-restricted manner. The specific involvement of ERα in hormone action opens new ways to identify drug targets that limit the inflammatory component of lung pathologies.

By a News Reporter-Staff News Editor at Women's Health Weekly -- A patent by the inventors Ashcroft, Gillian (Manchester, GB); Brufani, Mario (Castelgandolfo, IT); Ceccacci, Francesca (Rome, IT); Farina, Paolo [...]