scholarly journals HIF1α is a direct regulator of steroidogenesis in the adrenal gland

2021 ◽  
Author(s):  
Deepika Watts ◽  
Johanna Stein ◽  
Ana Meneses ◽  
Nicole Bechmann ◽  
Ales Neuwirth ◽  
...  
Keyword(s):  
Multiple Organ ◽  
Hypoxia Inducible Factors ◽  
Adrenocortical Cells ◽  
Steroid Production ◽  
Hormone Synthesis ◽  
Organ Systems ◽  
Direct Regulator ◽  
Endogenous Steroid ◽  
Endogenous Steroid Hormones

AbstractEndogenous steroid hormones, especially glucocorticoids and mineralocorticoids, derive from the adrenal cortex, and drastic or sustained changes in their circulatory levels affect multiple organ systems. Although hypoxia signaling in steroidogenesis has been suggested, knowledge on the true impact of the HIFs (Hypoxia-Inducible Factors) in the adrenocortical cells of vertebrates is scant. By creating a unique set of transgenic mouse lines, we reveal a prominent role for HIF1α in the synthesis of virtually all steroids in vivo. Specifically, mice deficient in HIF1α in adrenocortical cells displayed enhanced levels of enzymes responsible for steroidogenesis and a cognate increase in circulatory steroid levels. These changes resulted in cytokine alterations and changes in the profile of circulatory mature hematopoietic cells. Conversely, HIF1α overexpression resulted in the opposite phenotype of insufficient steroid production due to impaired transcription of necessary enzymes. Based on these results, we propose HIF1α to be a vital regulator of steroidogenesis as its modulation in adrenocortical cells dramatically impacts hormone synthesis with systemic consequences. In addition, these mice can have potential clinical significances as they may serve as essential tools to understand the pathophysiology of hormone modulations in a number of diseases associated with metabolic syndrome, auto-immunity or even cancer.

scholarly journals HIF1α is an essential regulator of steroidogenesis in the adrenal gland

2020 ◽  
Author(s):  
Deepika Watts ◽  
Johanna Stein ◽  
Ana Meneses ◽  
Nicole Bechmann ◽  
Ales Neuwirth ◽  
...  
Keyword(s):  
Adrenal Cortex ◽  
Oxygen Sensors ◽  
Multiple Organ ◽  
Hypoxia Inducible Factors ◽  
Adrenocortical Cells ◽  
Steroid Production ◽  
Hormone Synthesis ◽  
Organ Systems ◽  
Hif Prolyl Hydroxylase ◽  
Endogenous Steroid

AbstractEndogenous steroid hormones, especially glucocorticoids and mineralocorticoids, are essential for life regulating numerous physiological and pathological processes. These hormones derive from the adrenal cortex, and drastic or sustained changes in their circulatory levels affect multiple organ systems. Although a role for hypoxia pathway proteins (HPP) in steroidogenesis has been suggested, knowledge on the true impact of the HIFs (Hypoxia Inducible Factors) and oxygen sensors (HIF-prolyl hydroxylase domain-containing enzymes; PHDs) in the adrenocortical cells of vertebrates is scant. By creating a unique set of transgenic mouse lines, we reveal a prominent role for HIF1α in the synthesis of virtually all steroids under steady state conditions. Specifically, mice deficient in HIF1α in a part of the adrenocortical cells displayed enhanced levels of enzymes responsible for steroidogenesis and a cognate increase in circulatory steroid levels. These changes resulted in cytokine alterations and changes in the profile of circulatory mature hematopoietic cells. Conversely, HIF1α overexpression due to combined PHD2 and PHD3 deficiency in the adrenal cortex resulted in the opposite phenotype of insufficient steroid production due to impaired transcription of necessary enzymes. Based on these results, we propose HIF1α to be a central and vital regulator of steroidogenesis as its modulation in adrenocortical cells dramatically impacts hormone synthesis with systemic consequences. Additionally, these mice can have potential clinical significances as they may serve as essential tools to understand the pathophysiology of hormone modulations in a number of diseases associated with metabolic syndrome, auto-immunity or even cancer.

scholarly journals Neuroinvasion of SARS-CoV-2 in human and mouse brain

2021 ◽  
Vol 218 (3) ◽  
Author(s):  
Eric Song ◽  
Ce Zhang ◽  
Benjamin Israelow ◽  
Alice Lu-Culligan ◽  
Alba Vieites Prado ◽  
...  
Keyword(s):  
Cortical Neurons ◽  
Immune Cell ◽  
Multiple Organ ◽  
Type I ◽  
Organ Systems ◽  
The Central Nervous System ◽  
Interferon Responses ◽  
The Brain ◽  
Immune Cell Infiltrates

Although COVID-19 is considered to be primarily a respiratory disease, SARS-CoV-2 affects multiple organ systems including the central nervous system (CNS). Yet, there is no consensus on the consequences of CNS infections. Here, we used three independent approaches to probe the capacity of SARS-CoV-2 to infect the brain. First, using human brain organoids, we observed clear evidence of infection with accompanying metabolic changes in infected and neighboring neurons. However, no evidence for type I interferon responses was detected. We demonstrate that neuronal infection can be prevented by blocking ACE2 with antibodies or by administering cerebrospinal fluid from a COVID-19 patient. Second, using mice overexpressing human ACE2, we demonstrate SARS-CoV-2 neuroinvasion in vivo. Finally, in autopsies from patients who died of COVID-19, we detect SARS-CoV-2 in cortical neurons and note pathological features associated with infection with minimal immune cell infiltrates. These results provide evidence for the neuroinvasive capacity of SARS-CoV-2 and an unexpected consequence of direct infection of neurons by SARS-CoV-2.

A Non-Isotopic Method for Estimating 11β Hydroxysteroid Dehydrogenase Activity In Vivo

1997 ◽  
Vol 34 (5) ◽  
pp. 521-526 ◽  
Author(s):  
G R Bayly ◽  
W A Bartlett ◽  
A F Jones
Keyword(s):  
Hydroxysteroid Dehydrogenase ◽  
Steroid Production ◽  
Isotopic Method ◽  
Novel Approach ◽  
Large Numbers ◽  
Local Oxidation ◽  
Partial Deficiency ◽  
Dexamethasone Suppression ◽  
Endogenous Steroid

11 β-hydroxysteroid dehydrogenase (11βHSD) has both dehydrogenase (11βDH) and reductase (11βR) activities, which catalyse the interconversion of Cortisol and cortisone, and prednisolone and prednisone. This enzyme confers specificity on the mineralocorticoid receptor by local oxidation of Cortisol to cortisone. Using radiolabeled Cortisol 11βHSD activity has been shown to be lower in some cases of essential hypertension. This study investigated a novel approach to estimating 11βHSD activity in vivo. Plasma steroid kinetics were investigated following oral hydrocortisone (a substrate for 11βDH) and prednisone (a substrate for 11βR) in five normotensive volunteers after dexamethasone suppression of endogenous steroid production. This approach was evaluated by inducing partial deficiency of 11βHSD in the volunteers who took liquorice (to inhibit 11βDH) and then carbenoxolone (to inhibit both 11βDH and 11βR). The ratio of Cortisol to prednisolone (formed from prednisone) provided a measure of the activity of both 11βDH and 11βR. At 75min after the steroid bolus the ratio increased from 1·1 (0·6–1·3) (median, range) under control conditions to 1·2 (0·8–1·7) after liquorice ( P = 0·01, n = 5), and 2·0 (1·3–5·9) after carbenoxolone ( P = 0·02, n = 5). It may therefore be applied to the measurement of 11βHSD activity in vivo in large numbers of hypertensive patients without the use of radioisotopes.

scholarly journals Pleiotropic Phenotype of a Genomic Knock-In of an RGS-Insensitive G184S Gnai2 Allele

2006 ◽  
Vol 26 (18) ◽  
pp. 6870-6879 ◽  
Author(s):  
Xinyan Huang ◽  
Ying Fu ◽  
Raelene A. Charbeneau ◽  
Thomas L. Saunders ◽  
Douglas K. Taylor ◽  
...  
Keyword(s):  
Signal Transduction ◽  
G Protein ◽  
Cell Function ◽  
Immune Cell ◽  
Multiple Organ ◽  
Rgs Proteins ◽  
Total Contribution ◽  
Pleiotropic Phenotype ◽  
Organ Systems

ABSTRACT Signal transduction via guanine nucleotide binding proteins (G proteins) is involved in cardiovascular, neural, endocrine, and immune cell function. Regulators of G protein signaling (RGS proteins) speed the turn-off of G protein signals and inhibit signal transduction, but the in vivo roles of RGS proteins remain poorly defined. To overcome the redundancy of RGS functions and reveal the total contribution of RGS regulation at the Gαi2 subunit, we prepared a genomic knock-in of the RGS-insensitive G184S Gnai2 allele. The Gαi2 G184S knock-in mice show a dramatic and complex phenotype affecting multiple organ systems (heart, myeloid, skeletal, and central nervous system). Both homozygotes and heterozygotes demonstrate reduced viability and decreased body weight. Other phenotypes include shortened long bones, a markedly enlarged spleen, elevated neutrophil counts, an enlarged heart, and behavioral hyperactivity. Heterozygous Gαi2 +/G184S mice show some but not all of these abnormalities. Thus, loss of RGS actions at Gαi2 produces a dramatic and pleiotropic phenotype which is more evident than the phenotype seen for individual RGS protein knockouts.

scholarly journals mito-QC illuminates mitophagy and mitochondrial architecture in vivo

2016 ◽  
Vol 214 (3) ◽  
pp. 333-345 ◽  
Author(s):  
Thomas G. McWilliams ◽  
Alan R. Prescott ◽  
George F.G. Allen ◽  
Jevgenia Tamjar ◽  
Michael J. Munson ◽  
...  
Keyword(s):  
Quality Control ◽  
Cell Biology ◽  
Multiple Organ ◽  
Mitochondrial Morphology ◽  
In Vivo Detection ◽  
Developing Heart ◽  
Adult Kidney ◽  
Organ Systems ◽  
Essential Quality

Autophagic turnover of mitochondria, termed mitophagy, is proposed to be an essential quality-control (QC) mechanism of pathophysiological relevance in mammals. However, if and how mitophagy proceeds within specific cellular subtypes in vivo remains unclear, largely because of a lack of tractable tools and models. To address this, we have developed “mito-QC,” a transgenic mouse with a pH-sensitive fluorescent mitochondrial signal. This allows the assessment of mitophagy and mitochondrial architecture in vivo. Using confocal microscopy, we demonstrate that mito-QC is compatible with classical and contemporary techniques in histochemistry and allows unambiguous in vivo detection of mitophagy and mitochondrial morphology at single-cell resolution within multiple organ systems. Strikingly, our model uncovers highly enriched and differential zones of mitophagy in the developing heart and within specific cells of the adult kidney. mito-QC is an experimentally advantageous tool of broad relevance to cell biology researchers within both discovery-based and translational research communities.

scholarly journals Zinc Finger Protein Zbtb20 Is Essential for Postnatal Survival and Glucose Homeostasis

2009 ◽  
Vol 29 (10) ◽  
pp. 2804-2815 ◽  
Author(s):  
Andrew P. R. Sutherland ◽  
Hai Zhang ◽  
Ye Zhang ◽  
Monia Michaud ◽  
Zhifang Xie ◽  
...  
Keyword(s):  
Zinc Finger ◽  
Glucose Homeostasis ◽  
Knockout Mice ◽  
Target Genes ◽  
Zinc Finger Protein ◽  
Postnatal Growth ◽  
Multiple Organ ◽  
Wild Type Littermate ◽  
Organ Systems

ABSTRACT Zbtb20 is a member of the POK family of proteins, which function primarily as transcriptional repressors via interactions mediated by their conserved C2H2 Krüppel type zinc finger and BTB/POZ domains. To define the function of Zbtb20 in vivo, we generated knockout mice by homologous recombination. Zbtb20 null mice display a stark phenotype characterized by postnatal growth retardation, metabolic dysfunction, and lethality. Zbtb20 knockout mice displayed abnormal glucose homeostasis, hormonal responses, and depletion of energy stores, consistent with an energetic deficit. Additionally, increased serum bilirubin and alanine aminotransferase levels were suggestive of liver dysfunction. To identify potential liver-specific Zbtb20 target genes, we performed transcript profiling studies on liver tissue from Zbtb20 knockout mice and wild-type littermate controls. These studies identified sets of genes involved in growth, metabolism, and detoxification that were differentially regulated in Zbtb20 knockout liver. Transgenic mice expressing Zbtb20 in the liver were generated and crossed onto the Zbtb20 knockout background, which resulted in no significant normalization of growth or glucose metabolism but a significant increase in life span compared to controls. These data indicate that the phenotype of Zbtb20 knockout mice results from liver-dependent and -independent defects, suggesting that Zbtb20 plays nonredundant roles in multiple organ systems.

scholarly journals Lysophospholipid (S1P) receptors (version 2019.4) in the IUPHAR/BPS Guide to Pharmacology Database

2019 ◽  
Vol 2019 (4) ◽  
Author(s):  
Victoria Blaho ◽  
Jerold Chun ◽  
Deepa Jonnalagadda ◽  
Yasuyuki Kihara ◽  
Hirotaka Mizuno ◽  
...  
Keyword(s):  
Ligand Binding ◽  
Radioligand Binding ◽  
Cell Types ◽  
Receptor Activation ◽  
Multiple Organ ◽  
S1p Receptors ◽  
Organ Systems ◽  
Sphingosine 1 Phosphate ◽  
Heterologous Expression Systems

Sphingosine 1-phosphate (S1P) receptors (nomenclature as agreed by the NC-IUPHAR Subcommittee on Lysophospholipid receptors [70]) are activated by the endogenous lipid sphingosine 1-phosphate (S1P). Originally cloned as orphan members of the endothelial differentiation gene (edg) family, current gene names have been designated as S1P1R through S1P5R [52]. S1PRs, particularly S1P1, are expressed throughout all mammalian organ systems. Ligand delivery occurs via two known carriers (or "chaperones"): albumin and HDL-bound apolipoprotein M (ApoM), the latter of which elicits biased agonist signaling by S1P1 in multiple cell types [15, 39]. The five S1PRs, two chaperones, and active cellular metabolism have complicated analyses of receptor ligand binding in native systems. Signaling pathways and physiological roles have been characterized through radioligand binding in heterologous expression systems, targeted deletion of the different S1PRs, and most recently, mouse models that report in vivo S1P1R activation [74, 76]. A crystal structure of an S1P1-T4 fusion protein confirmed aspects of ligand binding, specificity, and receptor activation determined previously through biochemical and genetic studies [48, 14]. fingolimod (FTY720), the first drug to target any of the lysophospholipid receptors, binds to four of the five S1PRs, and was the first oral therapy for multiple sclerosis [26]. The mechanisms of action of fingolimod and other S1PR modulating drugs in development include binding S1PRs in multiple organ systems, e.g., immune and nervous systems, although the precise nature of their receptor interactions requires clarification [107, 28, 43, 44].

STEROIDOGENIC PATHWAYS AND TROPHIC RESPONSE TO ADRENOCORTICOTROPHIN OF CULTURED ADRENOCORTICAL CELLS IN DIFFERENT STATES OF DIFFERENTIATION

1976 ◽  
Vol 69 (3) ◽  
pp. 385-394 ◽  
Author(s):  
E. A. SLAVINSKI ◽  
J. W. JULL ◽  
N. AUERSPERG
Keyword(s):  
Cortical Cell ◽  
Cell Types ◽  
Culture Conditions ◽  
Acth Stimulation ◽  
Adrenocortical Cells ◽  
Steroid Production ◽  
Adult Rats ◽  
Adrenal Cell ◽  
Morphologic Changes

SUMMARY Adrenocortical cells obtained from adult rats were propagated in monolayer culture. Depending on culture conditions, they grew either as lipid-containing epithelial-like cells with a high level of steroid production, or as fibroblast-like cells with a low level of steroid production. The major fluorogenic steroid secreted by both morphologic forms of adrenal cortical cell was corticosterone as determined by chromatography and acid fluorometry. Basal fluorogenic steroid production per 106 cells over 24 h was: epithelial-like cells, 5·0 μg; fibroblast-like cells, 0·014 μg. Stimulation with ACTH for 5 days increased fluorogenic steroid production and induced morphologic changes in both adrenal cell forms. ACTH stimulation of fluorogenic steroid production by both cell forms reached a maximum after 3 days, then dropped to a refractory state after 5 days. With maximal ACTH stimulation, production increased 25-fold in fibroblast-like cells and five-fold in epithelial-like cells. The latter rate of corticosterone production is similar, per cell, to ACTH-stimulated adrenal glands in vivo. Progressive morphologic changes were observed with ACTH stimulation: epithelial-like cells retracted from the substratum and lost lipid inclusions; fibroblast-like cells became more epithelial-like. Both adrenal cell types formed intermediates from [4-14C]pregnenolone including pregn-5-ene-3β,20α-diol and 20α-hydroxypregn-4-en-3-one. Control cultures of muscle fascia fibroblasts did not produce corticosterone or intermediates from [4-14C]pregnenolone and did not respond to ACTH functionally or morphologically.

scholarly journals Neuroinvasion of SARS-CoV-2 in human and mouse brain

2020 ◽  
Author(s):  
Eric Song ◽  
Ce Zhang ◽  
Benjamin Israelow ◽  
Alice Lu-Culligan ◽  
Alba Vieites Prado ◽  
...  
Keyword(s):  
Cortical Neurons ◽  
Immune Cell ◽  
Multiple Organ ◽  
Cns Infection ◽  
Type I ◽  
Organ Systems ◽  
Pathologic Features ◽  
The Central Nervous System ◽  
The Brain

SummaryAlthough COVID-19 is considered to be primarily a respiratory disease, SARS-CoV-2 affects multiple organ systems including the central nervous system (CNS). Yet, there is no consensus whether the virus can infect the brain, or what the consequences of CNS infection are. Here, we used three independent approaches to probe the capacity of SARS-CoV-2 to infect the brain. First, using human brain organoids, we observed clear evidence of infection with accompanying metabolic changes in the infected and neighboring neurons. However, no evidence for the type I interferon responses was detected. We demonstrate that neuronal infection can be prevented either by blocking ACE2 with antibodies or by administering cerebrospinal fluid from a COVID-19 patient. Second, using mice overexpressing human ACE2, we demonstrate in vivo that SARS-CoV-2 neuroinvasion, but not respiratory infection, is associated with mortality. Finally, in brain autopsy from patients who died of COVID-19, we detect SARS-CoV-2 in the cortical neurons, and note pathologic features associated with infection with minimal immune cell infiltrates. These results provide evidence for the neuroinvasive capacity of SARS-CoV2, and an unexpected consequence of direct infection of neurons by SARS-CoV-2.

scholarly journals Lysophospholipid (S1P) receptors (version 2020.5) in the IUPHAR/BPS Guide to Pharmacology Database

2020 ◽  
Vol 2020 (5) ◽  
Author(s):  
Victoria Blaho ◽  
Jerold Chun ◽  
Danielle Jones ◽  
Deepa Jonnalagadda ◽  
Yasuyuki Kihara ◽  
...  
Keyword(s):  
Ligand Binding ◽  
Radioligand Binding ◽  
Cell Types ◽  
Receptor Activation ◽  
Multiple Organ ◽  
S1p Receptors ◽  
Organ Systems ◽  
Sphingosine 1 Phosphate ◽  
Heterologous Expression Systems

Sphingosine 1-phosphate (S1P) receptors (nomenclature as agreed by the NC-IUPHAR Subcommittee on Lysophospholipid receptors [86]) are activated by the endogenous lipid sphingosine 1-phosphate (S1P). Originally cloned as orphan members of the endothelial differentiation gene (edg) family, current gene names have been designated as S1P1R through S1P5R [66, 16, 109]. S1PRs, particularly S1P1, are expressed throughout all mammalian organ systems. Ligand delivery occurs via two known carriers (or "chaperones"): albumin and HDL-bound apolipoprotein M (ApoM), the latter of which elicits biased agonist signaling by S1P1 in multiple cell types [18, 48]. The five S1PRs, two chaperones, and active cellular metabolism have complicated analyses of receptor ligand binding in native systems. Signaling pathways and physiological roles have been characterized through radioligand binding in heterologous expression systems, targeted deletion of the different S1PRs, and most recently, mouse models that report in vivo S1P1R activation [91, 93]. A crystal structure of an S1P1-T4 fusion protein confirmed aspects of ligand binding, specificity, and receptor activation determined previously through biochemical and genetic studies [62, 17]. fingolimod (FTY720), the first drug to target any of the lysophospholipid receptors, binds to four of the five S1PRs, and was the first oral therapy for multiple sclerosis )MS) [32]. siponimod and ozanimod that target S1P1 and S1P5 are also FDA approved for the treatment of various MS forms [16, 109]. The mechanisms of action of fingolimod and other S1PR modulating drugs in development include binding S1PRs in multiple organ systems, e.g., immune and nervous systems, although the precise nature of their receptor interactions requires clarification [126, 34, 56, 57].

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