In addition to activating nuclear estrogen receptor signaling, 17β-estradiol can also regulate neuronal function via surface membrane receptors. In various brain regions, these actions are mediated by the direct association of estrogen receptors (ERs) activating metabotropic glutamate receptors (mGluRs). These ER/mGluR signaling partners are organized into discrete functional microdomains via caveolin proteins. A central question that remains concerns the underlying mechanism by which these subpopulations of ERs are targeted to the surface membrane. One candidate mechanism is S-palmitoylation, a posttranscriptional modification that affects the subcellular distribution and function of the modified protein, including promoting localization to membranes. Here we test for the role of palmitoylation and the necessity of specific palmitoylacyltransferase proteins in neuronal membrane ER action. In hippocampal neurons, pharmacological inhibition of palmitoylation eliminated 17β-estradiol-mediated phosphorylation of cAMP response element-binding protein, a process dependent on surface membrane ERs. In addition, mutation of the palmitoylation site on estrogen receptor (ER) α blocks ERα-mediated cAMP response element-binding protein phosphorylation. Similar results were obtained after mutation of the palmitoylation site on ERβ. Importantly, mutation of either ERα or ERβ did not affect the ability of the reciprocal ER to signal at the membrane. In contrast, membrane ERα and ERβ signaling were both dependent on the expression of the palmitoylacyltransferase proteins DHHC-7 and DHHC-21. Neither mGluR activity nor caveolin or ER expression was affected by knockdown of DHHC-7 and DHHC-21. These data collectively suggest discrete mechanisms that regulate specific isoform or global membrane ER signaling in neurons separate from mGluR activity or nuclear ER function.
17β-estradiol can rapidly modulate neuron function via membrane estrogen receptors (ERs) in a sex-specific manner. For example, female rat hippocampal neurons express palmitoylated versions of ERα and ERβ that associate with the plasma membrane. These membrane-associated ERs are organized by caveolin proteins into functional signaling microdomains with metabotropic glutamate receptors (mGluRs). ER/mGluR signaling mediates several sex-specific estradiol actions on hippocampal neuron function. An important unanswered question regards the mechanism by which sex-specific membrane-associated ER signaling is generated, especially since it has been previously demonstrated that mGluR action is not sex-specific. One possibility is that the genes necessary for the ER membrane complex are differentially expressed between males and females, including genes that encode ERα and β, caveolin 1 and 3, and/or the palmitoylacyltransferases DHHC-7 and -21. Thus we used qPCR to test the hypothesis that these genes show sex differences in expression in neonatal and adult rat hippocampus. As an additional control we tested the expression of the 20 other DHHC palmitoylacyltransferases with no known connections to ER. In neonatal hippocampus, no sex differences were detected in gene expression. In adult hippocampus, the genes that encode caveolin 1 and DHHC-7 showed decreased expression in females compared to males. Thus, select genes differ by sex at specific developmental stages, arguing for a more nuanced model than simple widespread perinatal emergence of sex differences in all genes enabling sex-specific estradiol action. These findings enable the generation of new hypotheses regarding the mechanisms by which sex differences in membrane-associated ER signaling are programmed.
Background: Children in the USA face increasing nutrition-related health risks, including obesity rates of 16.9% – a figure that has more than tripled over the past four decades. Nutrition education is beneficial to improve children’s health through obesity prevention and the promotion of healthy habits, and the elementary school years are a key time to implement health education interventions. Objective: To develop a medical student created and operated nutrition education intervention for urban underserved elementary school students. Design: The Food Doctors (TFD) programme is a hands-on, interactive, in-class nutrition education pilot initiative for elementary school students and adheres to the established tenets of effective in-class nutrition education whenever possible: (1) interactive hands-on curriculum, (2) use of culturally relevant topics and (3) the inclusion of effective evaluation techniques. Setting: Urban elementary school classrooms in Milwaukee, Wisconsin, USA. Method: A literature review and feedback from partner schools’ needs informed curriculum development. Institutional review board approval was sought and study materials prepared. The pilot programme was carried out at partner schools during class time. Results: A total of 83 students participated in the pilot study: 46 third-grade students and 37 fourth graders. Evaluation focused on assessing student baseline knowledge and exploring post-programme nutrition knowledge gains. Conclusion: TFD pilot programme demonstrated gaps in baseline nutrition knowledge among elementary school students and showed improved post-programme ability to correctly answer basic nutrition knowledge questions.
Congenital heart disease (CHD) is often associated with chronic extracardiac co-morbid conditions (ECC). The presence of ECC has been associated with greater resource utilization during the operative period; however, the impact beyond hospital discharge has not been described. This study sought to understand the scope of chronic ECC in infants with CHD as well as to describe the impact of ECC on resource utilization after discharge from the index cardiac procedure. IRB approved this retrospective study of infants <1 year who had cardiac surgery from 2006 and 2011. Demographics, diagnoses, procedures, STAT score, and ECC were extracted from the medical record. Administrative data provided frequency of clinic and emergency room visits, admissions, cumulative hospital days, and hospital charges for 2 years after discharge from the index procedure. Data were compared using Mann-Whitney Rank Sum Test with p < 0.05 considered significant. ECC occurred in 55% (481/876) of infants. Median STAT score was higher in the group with ECC (3 vs. 2, p < 0.001). Resource utilization after discharge from the index procedure as defined by median hospital charges (78 vs. 10 K, p < 0.001 and unplanned hospital days 4 vs. 0, p < 0.001) was higher in those with ECC, and increased with the greater number of ECC, even after accounting for surgical complexity. STAT score and the presence of multiple ECC were associated with higher resource utilization following the index cardiac surgical procedure. These data may be helpful in deciding which children might benefit from a cardiac complex care program that partners families and providers to improve health and decrease healthcare costs.
Group C Streptococcus (GCS) is part of the normal commensal flora of the upper airway, as well as frequently colonizes the skin, gastrointestinal tract, and female genital tract. It can also be implicated in mono- and polymicrobial infections of the skin and soft tissue, pharyngitis, bacteremia, endocarditis, septic arthritis, osteomyelitis, and meningitis. Our case study features a previously healthy 65-year-old male, who retired as a veterinarian one month prior, with Group C Streptococcus bacteremia complicated by septic polyarthritis, native mitral valve endocarditis, and lumbar discitis/osteomyelitis.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.