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Glucocorticoids acting via the glucocorticoid receptors (GR) are key regulators of metabolism and the stress response. However, uncontrolled or excessive GR signaling adversely affects adipose tissue, including endocrine, immune, and metabolic functions. Inflammation of the adipose tissue promotes systemic metabolic dysfunction; however, the molecular mechanisms underlying the role of adipocyte GR in regulating genes associated with adipose tissue inflammation are poorly understood. We performed in vivo studies using adipocyte-specific GR knockout mice in conjunction with in vitro studies to understand the contribution of adipocyte GR in regulating adipose tissue immune homeostasis. Our findings show that adipocyte-specific GR signaling regulates adipokines at both mRNA and plasma levels and immune regulatory (Coch, Pdcd1, Cemip, and Cxcr2) mRNA gene expression, which affects myeloid immune cell presence in white adipose tissue. We found that, in adipocytes, GR directly influences Cxcr2. This chemokine receptor promotes immune cell migration, indirectly affecting Pdcd1 and Cemip gene expression in nonadipocyte or stromal cells. Our findings suggest that GR adipocyte signaling suppresses inflammatory signals, maintaining immune homeostasis. We also found that GR signaling in adipose tissue in response to stress is sexually dimorphic. Understanding the molecular relationship between GR signaling and adipose tissue inflammation could help develop potential targets to improve local and systemic inflammation, insulin sensitivity, and metabolic health., (© The Author(s) 2023. Published by Oxford University Press on behalf of the Endocrine Society. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Mental stress is a risk factor for myocardial infarction in women. The central hypothesis of this study is that restraint stress induces sex-specific changes in gene expression in the heart, which leads to an intensified response to ischemia/reperfusion injury due to the development of a pro-oxidative environment in female hearts. We challenged male and female C57BL/6 mice in a restraint stress model to mimic the effects of mental stress. Exposure to restraint stress led to sex differences in the expression of genes involved in cardiac hypertrophy, inflammation, and iron-dependent cell death (ferroptosis). Among those genes, we identified tumor protein p53 and cyclin-dependent kinase inhibitor 1A (p21), which have established controversial roles in ferroptosis. The exacerbated response to I/R injury in restraint-stressed females correlated with downregulation of p53 and nuclear factor erythroid 2-related factor 2 (Nrf2, a master regulator of the antioxidant response system-ARE). S-female hearts also showed increased superoxide levels, lipid peroxidation, and prostaglandin-endoperoxide synthase 2 (Ptgs2) expression (a hallmark of ferroptosis) compared with those of their male counterparts. Our study is the first to test the sex-specific impact of restraint stress on the heart in the setting of I/R and its outcome.

Traumatic Brain Injury (TBI) is a primary cause of cerebrovascular and neurological disorders worldwide. The current scientific researchers believe that premorbid conditions such as tobacco smoking (TS) can exacerbate post-TBI brain injury and negatively affect recovery. This is related to vascular endothelial dysfunction resulting from the exposure to TS-released reactive oxygen species (ROS), nicotine, and oxidative stress (OS) stimuli impacting the blood-brain barrier (BBB) endothelium. Interestingly, these pathogenic modulators of BBB impairment are similar to those associated with hyperglycemia. Antidiabetic drugs such as metformin (MF) and rosiglitazone (RSG) were shown to prevent/reduce BBB damage promoted by chronic TS exposure. Thus, using in vivo approaches, we evaluated the effectiveness of post-TBI treatment with MF or RSG to reduce the TS-enhancement of BBB damage and brain injury after TBI. For this purpose, we employed an in vivo weight-drop TBI model using male C57BL/6J mice chronically exposed to TS with and without post-traumatic treatment with MF or RSG. Our results revealed that these antidiabetic drugs counteracted TS-promoted downregulation of nuclear factor erythroid 2-related factor 2 (NRF2) expression and concomitantly dampened TS-enhanced OS, inflammation, and loss of BBB integrity following TBI. In conclusion, our findings suggest that MF and RSG could reduce the harmful impact of chronic smoking on post-traumatic brain injuries.

Patients diagnosed with cancer often experience pain during their treatment course, making it difficult to care for themselves and continue with their activities of daily living. When cancer is found at later stages, the pain can become severe and constant; reducing their quality of life and significantly affecting mental and physical well-being. Despite opioids being known to provide adequate analgesia for higher pain levels, they are often the reason for under-dosing because of their adverse effects and concern for addiction. There are also patients who do not respond well to opioids because of genetic anomalies or personal preference. Therefore, there is a need for novel non-opioid cancer pain treatments. There are many new cancer pain treatments that are emerging. This manuscript discusses cancer pain, risk factors, epidemiology, guidelines for the treatment of cancer pain, personalization of cancer pain therapy, breakthrough pain, cancer-induced peripheral neuropathy, established cancer pain treatment options, and novel emerging cancer pain treatment options., (Published by Elsevier Masson SAS.)

Nonalcoholic fatty liver disease (NAFLD) is one of the most prevalent forms of chronic liver disease in the United States and worldwide. Nonalcoholic steatohepatitis (NASH), the most advanced form of NAFLD, is characterized by hepatic steatosis associated with inflammation and hepatocyte death. No treatments are currently available for NASH other than lifestyle changes, and the disease lacks specific biomarkers. The signaling lymphocytic activation molecule family 1 (SLAMF1) protein is a self-ligand receptor that plays a role in orchestrating an immune response to some pathogens and cancers. We found that livers from humans and mice with NASH showed a more prominent immunohistochemistry staining for SLAMF1 than non-NASH controls. Furthermore, SLAMF1 levels are significantly increased in NASH plasma samples from mice and humans compared with their respective controls. In mice, the levels of SLAMF1 correlated significantly with the severity of the NASH phenotype. To test whether SLAMF 1 is expressed by hepatocytes, HepG2 cells and primary murine hepatocytes were treated with palmitic acid (PA) to induce a state of lipotoxicity mimicking NASH. We found that PA treatments of HepG2 cells and primary hepatocytes lead to significant increases in SLAMF1 levels. The downregulation of SLAMF1 in HepG2 cells improved the cell viability and reduced cytotoxicity. The in vivo data using mouse and human NASH samples suggests a potential role for this protein as a noninvasive biomarker for NASH. The in vitro data suggest a role for SLAMF1 as a potential therapeutic target to prevent hepatocyte death in response to lipotoxicity. NEW & NOTEWORTHY This study identified for the first time SLAMF1 as a mediator of hepatocyte death in nonalcoholic fatty liver disease (NASH) and as a marker of NASH in humans. There are no pharmacological treatments available for NASH, and diagnostic tools are limited to invasive liver biopsies. Therefore, since SLAMF1 levels correlate with disease progression and SLAMF1 mediates cytotoxic effects, this protein can be used as a therapeutic target and a clinical biomarker of NASH.

When peripheral neuropathy occurs due to chemotherapy treatment, it is referred to as chemotherapy-induced peripheral neuropathy (CIPN). Typically, symptoms are sensory rather than motor and include reduced feeling and heightened sensitivity to pressure, pain, temperature, and touch. The pathophysiology of CIPN is very complex, and it involves multiple mechanisms leading to its development which will be described specifically for each chemotherapeutic class. There are currently no approved or effective agents for CIPN prevention, and Duloxetine is the only medication that is an effective treatment against CIPN. There is an unavoidable necessity to develop preventative and treatment approaches for CIPN due to its detrimental impact on patients' lives. The purpose of this review is to examine CIPN, innovative pharmacological and nonpharmacological therapy and preventive strategies for this illness, and future perspectives for this condition and its therapies., (Published by Elsevier Masson SAS.)

Cancer is the second most common cause of death in the United States and is a challenging disease to treat. The treatment options for various cancers include but are not limited to surgery, radiation, and chemotherapy. The mechanism behind chemotherapy is intended to promote cellular damage to cells that are proliferating uncontrollably. Unfortunately for the recipients, most chemotherapeutic agents cannot differentiate between malignant cells and healthy cells and tissues. Thus, chemotherapy-induced toxicities are often observed in once-healthy organs. These effects can be acute and self-limiting or chronic, appearing long after chemotherapy is completed. Cancer survivors can then present for non-cancer related surgeries later in life, due to this toxicity. Furthermore, the administration of chemotherapeutic agents can profoundly impact the anesthetic management of patients who are undergoing surgery. This review discusses how chemotherapy-induced organ toxicity can occur in multiple organ systems and what drugs should be avoided if prior toxicity exists in these organ systems., (Published by Elsevier Masson SAS.)

Purpose: Diabetic retinopathy is a vision-threatening complication of diabetes characterized by endothelial injury and vascular dysfunction. The loss of the endothelial glycocalyx, a dynamic layer lining all endothelial cells, contributes to several microvascular pathologies, including an increase in vascular permeability, leukocyte plugging, and capillary occlusion, and may drive the progression of retinopathy. Previously, a significant decrease in glycocalyx thickness has been observed in diabetic retinas. However, the effects of diabetes on specific components of the retinal glycocalyx have not yet been studied. Therefore, the aim of our study was to investigate changes in synthesis, expression, and shedding of retinal glycocalyx components induced by hyperglycemia, which could provide a novel therapeutic target for diabetic retinopathy., Methods: Primary rat retinal microvascular endothelial cells (RRMECs) were grown under normal glucose (5 mM) or high-glucose (25 mM) conditions for 6 days. The mRNA and protein levels of the glycocalyx components were examined using qRT-PCR and Western blot analysis, respectively. Further, mass spectrometry was used to analyze protein intensities of core proteins. In addition, the streptozotocin-induced Type 1 diabetic rat model was used to study changes in the expression of the retinal glycocalyx in vivo. The shedding of the glycocalyx was studied in both culture medium and in plasma using Western blot analysis., Results: A significant increase in the shedding of syndecan-1 and CD44 was observed both in vitro and in vivo under high-glucose conditions. The mRNA levels of syndecan-3 were significantly lower in the RRMECs grown under high glucose conditions, whereas those of syndecan-1, syndecan-2, syndecan-4, glypican-1, glypican-3, and CD44 were significantly higher. The protein expression of syndecan-3 and glypican-1 in RRMECs was reduced considerably following exposure to high glucose, whereas that of syndecan-1 and CD44 increased significantly. In addition, mass spectrometry data also suggests a significant increase in syndecan-4 and a significant decrease in glypican-3 protein levels with high glucose stimulation. In vivo, our data also suggest a significant decrease in the mRNA transcripts of syndecan-3 and an increase in mRNA levels of glypican-1 and CD44 in the retinas of diabetic rats. The diabetic rats exhibited a significant reduction in the retinal expression of syndecan-3 and CD44. However, the expression of syndecan-1 and glypican-1 increased significantly in the diabetic retina., Conclusions: One of the main findings of our study was the considerable diversity of glucose-induced changes in expression and shedding of various components of endothelial glycocalyx, for example, increased endothelial and retinal syndecan-1, but decreased endothelial and retinal syndecan-3. This indicates that the reported decrease in the retinal glycocalyx in diabetes in not a result of a non-specific shedding mechanism. Moreover, mRNA measurements indicated a similar diversity, with increases in endothelial and/or retinal levels of syndecan-1, glypican-1, and CD44, but a decrease for syndecan-3, with these increases in mRNA potentially a compensatory reaction to the overall loss of glycocalyx., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Background Stress has emerged as an important risk factor for heart disease in women. Stress levels have been shown to correlate with delayed recovery and increased mortality after a myocardial infarction. Therefore, we sought to investigate if the observed sex-specific effects of stress in myocardial infarction may be partly attributed to genomic interactions between the female sex hormones, estrogen (E2), and the primary stress hormones glucocorticoids. Methods and Results Genomewide studies show that glucocorticoids inhibit estrogen-mediated regulation of genes with established roles in cardiomyocyte homeostasis. These include 5-HT2BR (cardiac serotonin receptor 2B), the expression of which is critical to prevent cardiomyocyte death in the adult heart. Using siRNA, gene expression, and chromatin immunoprecipitation assays, we found that 5-HT2BR is a primary target of the glucocorticoid receptor and the estrogen receptor α at the level of transcription. The glucocorticoid receptor blocks the recruitment of estrogen receptor α to the promoter of the 5-HT2BR gene, which may contribute to the adverse effects of stress in the heart of premenopausal women. Using immunoblotting, TUNEL (terminal deoxynucleotidal transferase-mediated biotin-deoxyuridine triphosphate nick-end labeling), and flow cytometry, we demonstrate that estrogen decreases cardiomyocyte death by a mechanism relying on 5-HT2BR expression. In vitro and in vivo experiments show that glucocorticoids inhibit estrogen cardioprotection in response to hypoxia/reoxygenation injury and exacerbate the size of the infarct areas in myocardial infarction. Conclusions These results established a novel mechanism underlying the deleterious effects of stress on female cardiac health in the setting of ischemia/reperfusion.

The novel coronavirus disease 2019 (COVID-19) pandemic has created a significant health crisis worldwide. To mitigate this disease's spread, "social distancing" and "shelter in place" have been implemented. While these actions have been critical to controlling the pandemic, they have short- and long-term mental health consequences due to increased stress. There is a strong association between mental stress and cardiovascular disease (CVD). Young women (pre-menopausal) are at high risk of developing CV events in response to mental stress compared to age-matched men. The mechanisms underlying women's increased reactivity and response to stress are mostly unknown. The present review summarizes the known physiological consequences of mental stress in women's CV health and the latest molecular findings of the actions of the primary stress hormones, glucocorticoids, on the CV system. The current data suggest a clear link between psychological stress and heart disease, and women have an increased sensitivity to the harmful effects of stress hormone signaling imbalances. Therefore, it is expected that with the given unprecedented levels of stress associated with the COVID-19 pandemic, women's CV health will be significantly compromised. It is critical to widen our understanding of the direct contribution of mental stress to CVD risk in women and to identify biochemical markers with predictive value for CVD in female patients with/without cardiovascular conditions who have experienced significant mental stress during the current pandemic., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Dhaibar and Cruz-Topete.)

Virulent strains of Streptococcus pyogenes (gram-positive group A Streptococcus pyogenes [GAS]) recruit host single-chain human plasminogen (hPg) to the cell surface-where in the case of Pattern D strains of GAS, hPg binds directly to the cells through a surface receptor, plasminogen-binding group A streptococcal M-protein (PAM). The coinherited Pattern D GAS-secreted streptokinase (SK2b) then accelerates cleavage of hPg at the R 561 -V 562 peptide bond, resulting in the disulfide-linked two-chain protease, human plasmin (hPm). hPm localizes on the bacterial surface, assisting bacterial dissemination via proteolysis of host defense proteins. Studies using isolated domains from PAM and hPg revealed that the A-domain of PAM binds to the hPg kringle-2 module (K2 hPg ), but how this relates to the function of the full-length proteins is unclear. Herein, we use intact proteins to show that the lysine-binding site of K2 hPg is a major determinant of the activation-resistant T-conformation of hPg. The binding of PAM to the lysine-binding site of K2 hPg relaxes the conformation of hPg, leading to a greatly enhanced activation rate of hPg by SK2b. Domain swapping between hPg and mouse Pg emphasizes the importance of the Pg latent heavy chain (residues 1-561) in PAM binding and shows that while SK2b binds to both hPg and mouse Pg, the activation properties of streptokinase are strictly attributed to the serine protease domain (residues 562-791) of hPg. Overall, these data show that native hPg is locked in an activation-resistant conformation that is relaxed upon its direct binding to PAM, allowing hPm to form and provide GAS cells with a proteolytic surface., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)

A decline in normal physiological functions characterizes the aging process. While some of these changes are benign, the decrease in the function of the cardiovascular system that occurs during aging leads to the activation of pathological processes associated with an increased risk for heart disease and its complications. Imbalances in endocrine function are also common occurrences during the aging process. Glucocorticoids are primary stress hormones and are critical regulators of energy metabolism, inflammation, and cardiac function. Glucocorticoids exert their actions by binding the glucocorticoid receptor (GR) and, in some instances, to the mineralocorticoid receptor (MR). GR and MR are members of the nuclear receptor family of ligand-activated transcription factors. There is strong evidence that imbalances in GR and MR signaling in the heart have a causal role in cardiac disease. The extent to which glucocorticoids play a role in the aging heart, however, remains unclear. This review will summarize the positive and negative direct and indirect effects of glucocorticoids on the heart and the latest molecular and physiological evidence on how alterations in glucocorticoid signaling lead to changes in cardiac structure and function. We also briefly discuss the effects of other hormones systems such as estrogens and GH/IGF-1 on different cardiovascular cells during aging. We will also review the link between imbalances in glucocorticoid levels and the molecular processes responsible for promoting cardiomyocyte dysfunction in aging. Finally, we will discuss the potential for selectively manipulating glucocorticoid signaling in cardiomyocytes, which may represent an improved therapeutic approach for preventing and treating age-related heart disease., (Copyright © 2020 Cruz-Topete, Oakley and Cidlowski.)

The molecular and pharmacological manipulation of the endogenous redox system is a promising therapy to limit myocardial damage after a heart attack; however, antioxidant therapies have failed to fully establish their cardioprotective effects, suggesting that additional factors, including antioxidant system interactions with other molecular pathways, may alter the pharmacological effects of antioxidants. Since gender differences in cardiovascular disease (CVD) are prevalent, and sex is an essential determinant of the response to oxidative stress, it is of particular interest to understand the effects of sex hormone signaling on the activity and expression of cellular antioxidants and the pharmacological actions of antioxidant therapies. In the present review, we briefly summarize the current understanding of testosterone effects on the modulation of the endogenous antioxidant systems in the CV system, cardiomyocytes, and the heart. We also review the latest research on redox balance and sexual dimorphism, with particular emphasis on the role of the natural antioxidant system glutathione (GSH) in the context of myocardial infarction, and the pro- and antioxidant effects of testosterone signaling via the androgen receptor (AR) on the heart. Finally, we discuss future perspectives regarding the potential of using combing antioxidant and testosterone replacement therapies to protect the aging myocardium., Competing Interests: Declaration of competing interest The author(s) declare(s) that there is no conflict of interest regarding the publication of this article., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

Background The contribution of glucocorticoids to sexual dimorphism in the heart is essentially unknown. Therefore, we sought to determine the sexually dimorphic actions of glucocorticoid signaling in cardiac function and gene expression. To accomplish this goal, we conducted studies on mice lacking glucocorticoid receptors (GR) in cardiomyocytes (cardioGRKO mouse model). Methods and Results Deletion of cardiomyocyte GR leads to an increase in mortality because of the development of spontaneous cardiac pathology in both male and female mice; however, females are more resistant to GR signaling inactivation in the heart. Male cardioGRKO mice had a median survival age of 6 months. In contrast, females had a median survival age of 10 months. Transthoracic echocardiography data showed phenotypic differences between male and female cardioGRKO hearts. By 3 months of age, male cardioGRKO mice exhibited left ventricular systolic dysfunction. Conversely, no significant functional deficits were observed in female cardioGRKO mice at the same time point. Functional sensitivity of male hearts to the loss of cardiomyocyte GR was reversed following gonadectomy. RNA-Seq analysis showed that deleting GR in the male hearts leads to a more profound dysregulation in the expression of genes implicated in heart rate regulation (calcium handling). In agreement with these gene expression data, cardiomyocytes isolated from male cardioGRKO hearts displayed altered intracellular calcium responses. In contrast, female GR-deficient cardiomyocytes presented a response comparable with controls. Conclusions These data suggest that GR regulates calcium responses in a sex-biased manner, leading to sexually distinct responses to stress in male and female mice hearts, which may contribute to sex differences in heart disease, including the development of ventricular arrhythmias that contribute to heart failure and sudden death.

Stress is increasingly associated with heart dysfunction and is linked to higher mortality rates in patients with cardiometabolic disease. Glucocorticoids are primary stress hormones that regulate homeostasis through two nuclear receptors, the glucocorticoid receptor (GR) and mineralocorticoid receptor (MR), both of which are present in cardiomyocytes. To examine the specific and coordinated roles that these receptors play in mediating the direct effects of stress on the heart, we generated mice with cardiomyocyte-specific deletion of GR (cardioGRKO), MR (cardioMRKO), or both GR and MR (cardioGRMRdKO). The cardioGRKO mice spontaneously developed cardiac hypertrophy and left ventricular systolic dysfunction and died prematurely from heart failure. In contrast, the cardioMRKO mice exhibited normal heart morphology and function. Despite the presence of myocardial stress, the cardioGRMRdKO mice were resistant to the cardiac remodeling, left ventricular dysfunction, and early death observed in the cardioGRKO mice. Gene expression analysis revealed the loss of gene changes associated with impaired Ca 2+ handling, increased oxidative stress, and enhanced cell death and the presence of gene changes that limited the hypertrophic response and promoted cardiomyocyte survival in the double knockout hearts. Reexpression of MR in cardioGRMRdKO hearts reversed many of the cardioprotective gene changes and resulted in cardiac failure. These findings reveal a critical role for balanced cardiomyocyte GR and MR stress signaling in cardiovascular health. Therapies that shift stress signaling in the heart to favor more GR and less MR activity may provide an improved approach for treating heart disease., (Copyright © 2019 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)

The collective of endocrine organs acting in homeostatic regulation-known as the hypothalamic-pituitary-adrenal (HPA) axis-comprises an integration of the central nervous system as well as peripheral tissues. These organs respond to imminent or perceived threats that elicit a stress response, primarily culminating in the release of glucocorticoids into the systemic circulation by the adrenal glands. Although the secretion of glucocorticoids serves to protect and maintain homeostasis in the typical operation at baseline levels, inadequate regulation can lead to physiologic and psychologic pathologies. The cardiovascular system is especially susceptible to prolonged dysregulation of the HPA axis and glucocorticoid production. There is debate about whether cardiovascular health risks arise from the direct detrimental effects of stress axis activation or whether pathologies develop secondary to the accompanying metabolic strain of excess glucocorticoids. In this review, we will explore the emerging research that indicates stress does have direct effects on the cardiovascular system via the HPA axis activation, with emphasis on the latest research on the impact of glucocorticoids signaling in the vasculature and the heart., Competing Interests: The authors declare no conflicts of interest.

Glucocorticoid receptor (GR) signaling has recently been shown to play a direct role in the regulation of cardiomyocyte function. In this study, we investigated the potential role of KLF13 as a downstream effector of GR action utilizing both in vivo and in vitro approaches. Our data show that KLF13 mRNA and protein levels are significantly diminished in the hearts of mice lacking GR in cardiomyocytes. Glucocorticoid administration up-regulated Klf13 mRNA in the mouse heart, in isolated primary cardiomyocytes, and in immortal cardiomyocyte cell lines. Glucocorticoid Klf13 gene expression was abolished by treatment with a GR antagonist (RU486) or by knockdown of GR in cardiomyocytes. Moreover, glucocorticoid induction of Klf13 mRNA was resistant to de novo protein synthesis inhibition, demonstrating that Klf13 is a direct glucocorticoid receptor gene target. A glucocorticoid responsive element (GRE) was identified in the Klf13 gene and its function was verified by chromatin immunoprecipitation in HL-1 cells and mouse hearts. Functional studies showed that GR regulation of Klf13 is critical to protect cardiomyocytes from DNA damage and cell death induced by cobalt(II) chloride hexahydrate (CoCl2·6H2O) and the antineoplastic drug doxorubicin. These results established a novel role for GR and KLF13 signaling in adult cardiomyocytes with potential clinical implications for the prevention of cardiotoxicity induced heart failure., (© 2016 by The American Society for Biochemistry and Molecular Biology, Inc.)

Activation of the hypothalamic-pituitary-adrenal axis results in the release of hormones from the adrenal glands, including glucocorticoids and mineralocorticoids. The physiological association between corticosteroids and cardiac disease is becoming increasingly recognized; however, the mechanisms underlying this association are not well understood. To determine the biological effects of corticosteroids on the heart, we investigated the impact of adrenalectomy in C57BL/6 male mice. Animals were adrenalectomized (ADX) at 1 month of age and maintained for 3-6 months after surgery to evaluate the effects of long-term adrenalectomy on cardiac function. Morphological evaluation suggested that ADX mice showed significantly enlarged hearts compared with age-matched intact controls. These changes in morphology correlated with deficits in left ventricular (LV) function and electrocardiogram (ECG) abnormalities in ADX mice. Correlating with these functional defects, gene expression analysis of ADX hearts revealed aberrant expression of a large cohort of genes associated with cardiac hypertrophy and arrhythmia. Combined corticosterone and aldosterone replacement treatment prevented the emergence of cardiac abnormalities in ADX mice, whereas corticosterone replacement prevented the effects of adrenalectomy on LV function but did not block the emergence of ECG alterations. Aldosterone replacement did not preserve the LV function but prevented ECG abnormalities. Together, the data indicate that adrenal glucocorticoids and mineralocorticoids either directly or indirectly have selective effects in the heart and their signaling pathways are essential in maintaining normal cardiac function.

While in vitro studies have demonstrated that a glucocorticoid receptor (GR) splice isoform, β-isoform of human GR (hGRβ), acts as a dominant-negative inhibitor of the classic hGRα and confers glucocorticoid resistance, the in vivo function of hGRβ is poorly understood. To this end, we created an adeno-associated virus (AAV) to express hGRβ in the mouse liver under the control of the hepatocyte-specific promoter. Genome-wide expression analysis of mouse livers showed that hGRβ significantly increased the expression of numerous genes, many of which are involved in endocrine system disorders and the inflammatory response. Physiologically, hGRβ antagonized GRα's function and attenuated hepatic gluconeogenesis through downregulation of phosphoenolpyruvate carboxykinase (PEPCK) in wild-type (WT) mouse liver. Interestingly, however, hGRβ did not repress PEPCK in GR liver knockout (GRLKO) mice. In contrast, hGRβ regulates the expression of STAT1 in the livers of both WT and GRLKO mice. Chromatin immunoprecipitation (ChIP) and luciferase reporter assays demonstrated that hGRβ binds to the intergenic glucocorticoid response element (GRE) of the STAT1 gene. Furthermore, treatment with RU486 inhibited the upregulation of STAT1 mediated by hGRβ. Finally, our array data demonstrate that hGRβ regulates unique components of liver gene expression in vivo by both GRα-dependent and GRα-independent mechanisms., (Copyright © 2016, American Society for Microbiology. All Rights Reserved.)

Glucocorticoids are essential steroid hormones secreted from the adrenal gland in response to stress. Since their discovery in the 1940s, glucocorticoids have been widely prescribed to treat inflammatory disorders and hematological cancers. In the traditional view, glucocorticoids are regarded as anti-inflammatory molecules; however, emerging evidence suggests that glucocorticoid actions are more complex than previously anticipated. The anti-inflammatory activity of glucocorticoids is attributed to the repression of pro-inflammatory genes through signal transduction by their steroid receptor, the glucocorticoid receptor (GR). The mechanisms modulating the pro-inflammatory effects of glucocorticoids are not well understood. In this review, we discuss recent findings that provide insights into the mechanism by which GR signaling can play a dual role in the regulation of the immune response. We hypothesize that these apparently opposite processes are working together to prepare the immune system to respond to a stressor (pro-inflammatory effects) and subsequently restore homeostasis (anti-inflammatory effects). Finally, we propose that determining the mechanisms which underlie the tissue-specific effects of glucocorticoids will provide an excellent tool to develop more efficient and selective glucocorticoid therapies., (© 2014 S. Karger AG, Basel.)

Heart failure is a leading cause of death in humans, and stress is increasingly associated with adverse cardiac outcomes. Glucocorticoids are primary stress hormones, but their direct role in cardiovascular health and disease is poorly understood. To determine the in vivo function of glucocorticoid signaling in the heart, we generated mice with cardiomyocyte-specific deletion of the glucocorticoid receptor (GR). These mice are born at the expected Mendelian ratio, but die prematurely from spontaneous cardiovascular disease. By 3 mo of age, mice deficient in cardiomyocyte GR display a marked reduction in left ventricular systolic function, as evidenced by decreases in ejection fraction and fractional shortening. Heart weight and left ventricular mass are elevated, and histology revealed cardiac hypertrophy without fibrosis. Removal of endogenous glucocorticoids and mineralocorticoids neither augmented nor lessened the hypertrophic response. Global gene expression analysis of knockout hearts before pathology onset revealed aberrant regulation of a large cohort of genes associated with cardiovascular disease as well as unique disease genes associated with inflammatory processes. Genes important for maintaining cardiac contractility, repressing cardiac hypertrophy, promoting cardiomyocyte survival, and inhibiting inflammation had decreased expression in the GR-deficient hearts. These findings demonstrate that a deficiency in cardiomyocyte glucocorticoid signaling leads to spontaneous cardiac hypertrophy, heart failure, and death, revealing an obligate role for GR in maintaining normal cardiovascular function. Moreover, our findings suggest that selective activation of cardiomyocyte GR may represent an approach for the prevention of heart disease.

Glucocorticoids and their synthetic derivatives are known to alter cardiac function in vivo; however, the nature of these effects and whether glucocorticoids act directly on cardiomyocytes are poorly understood. To explore the role of glucocorticoid signaling in the heart, we used rat embryonic H9C2 cardiomyocytes and primary cardiomyocytes as model systems. Dexamethasone (100 nm) treatment of cardiomyocytes caused a significant increase in cell size and up-regulated the expression of cardiac hypertrophic markers, including atrial natriuretic factor, β-myosin heavy chain, and skeletal muscle α-actin. In contrast, serum deprivation and TNFα exposure triggered cardiomyocyte apoptosis, and these apoptotic effects were inhibited by dexamethasone. Both the hypertrophic and anti-apoptotic actions of glucocorticoids were abolished by the glucocorticoid receptor (GR) antagonist RU486 and by short hairpin RNA-mediated GR depletion. Blocking the activity of the mineralocorticoid receptor had no effect on these glucocorticoid-dependent cardiomyocyte responses. Aldosterone (1 μm) activation of GR also promoted cardiomyocyte hypertrophy and cell survival. To elucidate the mechanism of the dual glucocorticoid actions, a genome-wide microarray was performed on H9C2 cardiomyocytes treated with vehicle or dexamethasone in the absence or presence of serum. Serum dramatically influenced the transcriptome regulated by GR, revealing potential glucocorticoid signaling mediators in both cardiomyocyte hypertrophy and apoptosis. These studies reveal a direct and dynamic role for glucocorticoids and GR signaling in the modulation of cardiomyocyte function.

Unlabelled: In most obese patients there is an inflammatory state characterized by lipid abnormalities, hyperleptinemia and hyperinsulinemia., Objective: The objective was to identify mechanisms involved in leptin's role in the attenuation of the response to insulin using a proteomic approach., Material/methods: We studied the serum proteomic profile of rats treated by central leptin infusion followed by an injection of insulin. We analyzed the relationship between these proteins and serum cytokine and apolipoprotein levels., Results: Out of 81 protein spots, intensity differences were found in 11, corresponding to 5 proteins: three isoforms of α1 macroglobulin; three of haptoglobin and serum amyloid P component-precursor. All of these are acute-phase proteins involved in inflammation and are correlated with cytokine levels. Additionally, two apolipoprotein E and two apolipoprotein A1 isoforms were identified and were found to correlate with LDL and HDL., Conclusions: Our results indicate that increased leptin and insulin levels change these circulating proteins, thus promoting systemic inflammation and changing lipid metabolism., (Copyright © 2012 Elsevier Inc. All rights reserved.)

Context: GH secretion peaks at puberty and continues to be secreted in adulthood, albeit at a declining rate. Profound GH deficiency (GHD) in adults with pituitary disease is associated with symptoms that improve with GH substitution, but it is important to tailor the GH dose to avoid overtreatment. Measurement of serum IGF-I levels is an important clinical tool in this regard, but it is well recognized that some patients receiving GH treatment do not show an increase in IGF-I., Objective: The objective of the study was to identify novel serum biomarkers of GH treatment in adults with GHD., Design and Patients: Eight patients with profound GHD as a consequence of a pituitary adenoma or its treatment were evaluated before and 3 months after GH replacement therapy (0.2-0.4 mg/d)., Main Outcome Measures: Serum proteomic changes were studied using two-dimensional gel electrophoresis and mass spectrometry. Protein profiles were analyzed and compared in serum samples obtained before and after GH treatment., Results: The levels of six serum protein spots were significantly altered after GH substitution. These proteins were identified as five isoforms of haptoglobin (decreased in posttreatment samples) and one isoform of apolipoprotein A-I (increased in posttreatment samples). Importantly, changes in the levels of the identified proteins were associated with decreases in fat mass and increases in lean mass in all patients. These results were independent of serum IGF-I levels., Conclusions: Evaluation of the identified proteins provides a novel alternative to traditional markers of GH status, such as serum IGF-I levels, to assess GH therapy in GH deficient adults.

Disruption of the GH receptor (GHR) gene eliminates GH-induced intracellular signaling and, thus, its biological actions. Therefore, the GHR gene disrupted mouse (GHR-/-) has been and is a valuable tool for helping to define various parameters of GH physiology. Since its creation in 1995, this mouse strain has been used by our laboratory and others for numerous studies ranging from growth to aging. Some of the most notable discoveries are their extreme insulin sensitivity in the presence of obesity. Also, the animals have an extended lifespan, which has generated a large number of investigations into the roles of GH and IGF-I in the aging process. This review summarizes the many results derived from the GHR-/- mice. We have attempted to present the findings in the context of current knowledge regarding GH action and, where applicable, to discuss how these mice compare to GH insensitivity syndrome in humans.

The development of type 2 diabetes (T2D) is strongly associated with obesity. In humans, T2D increases the risk for end organ complications. Among these, heart disease has been ranked as the leading cause of death. We used a proteomic methodology to test the hypothesis that a pre-diabetic state generated by high-fat diet leads to changes in proteins related to heart function and structure. Over 300 protein spots were resolved by two-dimensional gel electrophoresis (2-DE). Fifteen protein spots were found to be altered (7 decreased and 8 increased) in pre-diabetic hearts. The protein spots were then identified by mass spectrometry and immunoblots. Among the decreased proteins, 3 are involved in heart structure (one isoform of desmin, troponin T2 and α-cardiac actin), 3 are involved in energy metabolism (mitochondrial ATP synthase β subunit, adenylate kinase and creatine kinase) and one is a component of the citric acid cycle (isocitrate dehydrogenase 3). In contrast, proteins involved in fatty acid oxidation (two isoforms of peroxisomal enoyl-CoA hydratase) and the citric acid cycle (three isoforms of malate dehydrogenase) were increased in pre-diabetic hearts. The results suggest that changes in the levels of several heart proteins may have implications in the development of the cardiac phenotype associated to T2D., (Copyright © 2011 Elsevier B.V. All rights reserved.)

Context: Transsphenoidal adenomectomy is the primary treatment for acromegaly. However, assessment of the therapeutical outcome remains problematic since the existing biomarkers of disease activity frequently show discordant results., Objective: To discover novel serum biomarkers of disease activity in acromegalic patients before and after surgery., Design: Serum samples of eight newly diagnosed acromegaly patients before and after transsphenoidal surgery were analyzed for proteomic changes by two-dimensional gel electrophoresis. Protein spots displaying statistically significant changes, pre- versus post-surgery, were identified by mass spectrometry (MS), tandem MS (MS/MS), and western blot analysis., Results: Six protein spots displaying decreased intensities after surgery were identified as transthyretin (two isoforms), haptoglobin α2, β-hemoglobin, and apolipoprotein A-1 (two isoforms). One protein spot, identified as complement C4B precursor, was increased after the surgery., Conclusions: Seven serum protein spots were differentially expressed following surgery in acromegalic patients. The identified proteins represent potential novel biomarkers to assess the effectiveness of surgical treatment in acromegalic individuals. Future studies will validate the use of the identified proteins as biomarkers of disease activity after medical treatment of acromegaly.

Erythropoietin (Epo) is produced primarily in the kidneys upon low blood oxygen availability and stimulates erythropoiesis in the bone marrow. Recombinant human Epo (rHuEpo), a drug developed to increase arterial oxygen content in patients, is also illicitly used by athletes to improve their endurance performance. Therefore, a robust and sensitive test to detect its abuse is needed. The aim of the present study was to investigate potential human serum biomarkers of Epo abuse employing a proteomic approach. Eight healthy male subjects were injected subcutaneously with rHuEpo (5,000 IU) every second day for a 16-day period. Serum was collected before starting the treatment regime and again at days 8 and 16 during the treatment period. Samples were homogenized and proteins separated by two-dimensional gel electrophoresis (2DE). Spots that changed significantly in response to rHuEpo treatment were identified by mass spectrometry. Both the number of reticulocytes and erythrocytes increased throughout the study, leading to a significant increase in hematocrit and hemoglobin content. In addition, transferrin levels increased but the percentage of iron bound to transferrin and ferritin levels decreased. Out of 97 serum proteins, seven were found to decrease significantly at day 16 compared with pre-Epo administration, and were identified as four isoforms of haptoglobin, two isoforms of transferrin, and a mixture of hemopexin and albumin. In support, total serum haptoglobin levels were found to be significantly decreased at both days 8 and 16. Thus a 2DE proteomic approach for discovery of novel markers of Epo action appears feasible.