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Ouyang S, Liu C, Xiao J, Chen X, Lui AC, Li X. Targeting IL-17A/glucocorticoid synergy to CSF3 expression in neutrophilic airway diseases. JCI Insight 2020; 5:132836. [PMID: 32051346 DOI: 10.1172/jci.insight.132836] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2019] [Accepted: 01/08/2020] [Indexed: 12/15/2022] Open
Abstract
IL-17A plays a critical role in the pathogenesis of steroid-resistant neutrophilic airway inflammation, which is a hallmark of severe asthma and chronic obstructive pulmonary disease (COPD). Through RNA sequencing analysis of transcriptomes of human airway smooth muscle cells treated with IL-17A, dexamethasone (DEX, a synthetic glucocorticoid drug), alone or in combination, we identified a group of genes that are synergistically induced by IL-17A and DEX, including the neutrophil-promoting cytokine CSF3. In type-17 (Th17/IL-17Ahi) preclinical models of neutrophilic severe asthma (acute and chronic) and COPD, although DEX treatment was able to reduce the expression of neutrophil-mobilizing CXCL1 and CXCL2 in lung tissue, CSF3 expression was upregulated by DEX treatment. We found that DEX treatment alone failed to alleviate neutrophilic airway inflammation and pathology, and even exacerbated the disease phenotype when CSF3 was highly induced. Disruption of the IL-17A/DEX synergy by IL-17A inhibition with anti-IL-17A mAb or cyanidin-3-glucoside (C3G, a small-molecule IL-17A blocker) or depletion of CSF3 effectively rendered DEX sensitivity in type-17 preclinical models of neutrophilic airway diseases. Our study elucidates what we believe is a novel mechanism of steroid resistance in type-17 neutrophilic airway inflammation and offers an effective steroid-sparing therapeutic strategy (combined low-dose DEX and C3G) for treating neutrophilic airway diseases.
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Chu FF, Esworthy RS, Shen B, Gao Q, Doroshow JH. Dexamethasone and Tofacitinib suppress NADPH oxidase expression and alleviate very-early-onset ileocolitis in mice deficient in GSH peroxidase 1 and 2. Life Sci 2019; 239:116884. [PMID: 31689440 PMCID: PMC6898790 DOI: 10.1016/j.lfs.2019.116884] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2019] [Revised: 09/15/2019] [Accepted: 09/16/2019] [Indexed: 12/25/2022]
Abstract
C57BL6/J (B6) mice lacking Se-dependent GSH peroxidase 1 and 2 (GPx1/2-DKO) develop mild to moderate ileocolitis around weaning. These DKO mice have a disease resembling human very-early-onset inflammatory bowel disease (VEOIBD), which is associated with mutations in NADPH oxidase genes. Drugs including dexamethasone (Dex), Tofacitinib (Tofa; a Janus kinase/JAK inhibitor) and anti-TNF antibody are effective to treat adult, but not pediatric IBD. AIMS To test the efficacy of hydrophobic Dex and hydrophilic Dex phosphate (Dex phos), Tofa, anti-Tnf Ab, Noxa1ds-TAT and gp91ds-TAT peptides (inhibiting NOX1 and NOX2 assembly respectively), antioxidant MJ33 and ML090, and pifithrin-α (p53 inhibitor) on alleviation of gut inflammation in DKO weanlings. MAIN METHODS All treatments began on 22-day-old GPx1/2-DKO mice. The mouse intestine pathology was compared between the drug- and vehicle-treated groups after six or thirteen days of treatment. KEY FINDINGS Among all drugs tested, Dex, Dex phos and Tofa were the strongest to suppress ileocolitis in the DKO weanlings. Dex, Dex phos and Tofa inhibited crypt apoptosis and increased crypt density. Dex or Dex phos alone also inhibited cell proliferation, exfoliation and crypt abscess in the ileum. Dex, but not Tofa, retarded mouse growth. Both Dex and Tofa inhibited ileum Nox1, Nox4 and Duox2, but not Nox2 gene expression. Noxa1ds-TAT and gp91ds-TAT peptides as well as MJ33 had subtle effect on suppressing pathology, while others had negligible effect. SIGNIFICANCE These findings suggest that NADPH oxidases can be novel drug targets for pediatric IBD therapy, and Tofa may be considered for treating VEOIBD.
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Funes SC, Ríos M, Gómez‐Santander F, Fernández‐Fierro A, Altamirano‐Lagos MJ, Rivera‐Perez D, Pulgar‐Sepúlveda R, Jara EL, Rebolledo‐Zelada D, Villarroel A, Roa JC, Mackern‐Oberti JP, Kalergis AM. Tolerogenic dendritic cell transfer ameliorates systemic lupus erythematosus in mice. Immunology 2019; 158:322-339. [PMID: 31509246 PMCID: PMC6856940 DOI: 10.1111/imm.13119] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2019] [Revised: 08/28/2019] [Accepted: 09/05/2019] [Indexed: 12/11/2022] Open
Abstract
Current treatments for systemic autoimmune diseases partially improve the health of patients displaying low pharmacological efficacy and systemic immunosuppression. Here, the therapeutic potential of transferring tolerogenic dendritic cells (tolDCs) generated with heme-oxygenase inductor cobalt (III) protoporphyrin IX (CoPP), dexamethasone and rosiglitazone for the treatment of systemic autoimmunity was evaluated in two murine models of systemic lupus erythematosus (SLE), MRL-Faslpr and NZM2410 mice. Dendritic cells treated ex vivo with these drugs showed a stable tolerogenic profile after lipopolysaccharide stimulation. Regular doses of tolDCs were administered to anti-nuclear antibody-positive mice throughout 60-70 days, and the clinical score was evaluated. Long-term treatment with these tolDCs was well tolerated and effective to improve the clinical score on MRL-Faslpr lupus-prone mice. Additionally, decreased levels of anti-nuclear antibodies in NZM2410 mice were observed. Although tolDC treatment increased regulatory T cells, no significant reduction of renal damage or glomerulonephritis could be found. In conclusion, these results suggest that the transfer of histone-loaded tolDCs could improve only some SLE symptoms and reduced anti-nuclear antibodies. This is the first study to evaluate antigen-specific tolDC administration to treat SLE. Our report strengthens the clinical relevance of tolDC generation with CoPP, dexamethasone and rosiglitazone and the use of these modified cells as a therapy for systemic autoimmunity.
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Cederroth CR, Park JS, Basinou V, Weger BD, Tserga E, Sarlus H, Magnusson AK, Kadri N, Gachon F, Canlon B. Circadian Regulation of Cochlear Sensitivity to Noise by Circulating Glucocorticoids. Curr Biol 2019; 29:2477-2487.e6. [PMID: 31353184 PMCID: PMC6904421 DOI: 10.1016/j.cub.2019.06.057] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2018] [Revised: 05/21/2019] [Accepted: 06/20/2019] [Indexed: 01/27/2023]
Abstract
The cochlea possesses a robust circadian clock machinery that regulates auditory function. How the cochlear clock is influenced by the circadian system remains unknown. Here, we show that cochlear rhythms are system driven and require local Bmal1 as well as central input from the suprachiasmatic nuclei (SCN). SCN ablations disrupted the circadian expression of the core clock genes in the cochlea. Because the circadian secretion of glucocorticoids (GCs) is controlled by the SCN and GCs are known to modulate auditory function, we assessed their influence on circadian gene expression. Removal of circulating GCs by adrenalectomy (ADX) did not have a major impact on core clock gene expression in the cochlea. Rather it abolished the transcription of clock-controlled genes involved in inflammation. ADX abolished the known differential auditory sensitivity to day and night noise trauma and prevented the induction of GABA-ergic and glutamate receptors mRNA transcripts. However, these improvements were unrelated to changes at the synaptic level, suggesting other cochlear functions may be involved. Due to this circadian regulation of noise sensitivity by GCs, we evaluated the actions of the synthetic glucocorticoid dexamethasone (DEX) at different times of the day. DEX was effective in protecting from acute noise trauma only when administered during daytime, when circulating glucocorticoids are low, indicating that chronopharmacological approaches are important for obtaining optimal treatment strategies for hearing loss. GCs appear as a major regulator of the differential sensitivity to day or night noise trauma, a mechanism likely involving the circadian control of inflammatory responses.
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Si D, Xiong Y, Yang Z, Zhang J, Ma L, Li J, Wang Y. Whole genome sequencing analysis of a dexamethasone-degrading Burkholderia strain CQ001. Medicine (Baltimore) 2019; 98:e16749. [PMID: 31415371 PMCID: PMC6831421 DOI: 10.1097/md.0000000000016749] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
This study is to analyze the functional genes and metabolic pathways of dexamethasone degradation in Burkholderia through genome sequencing.A new Burkholderia sp. CQQ001 (B. CQ001) with dexamethasone degrading activity was isolated from the hospital wastewater and sequenced using Illumina Hiseq4000 combined with the third-generation sequencing technology. The genomes were assembled, annotated, and genomically mapped. Compared with six Burkholderia strains with typical features and four Burkholderia strains with special metabolic ability, the functional genes and metabolic pathways of dexamethasone degradation were analyzed and confirmed by RT-qPCR.Genome of B. CQ001 was 7,660,596 bp long with 6 ring chromosomes. The genes related to material metabolism accounted for 80.15%. These metabolism related genes could participate in 117 metabolic pathways and cover various microbial metabolic pathways in different environments and decomposition pathways of secondary metabolites, especially the degradation of aromatic compounds. The steroidal metabolic pathway containing 1 ABC transporter and 9 key metabolic enzymes related genes were scattered in the genome. Among them, the ABC transporter, KshA, and KshB increased significantly under the culture conditions of dexamethasone sodium phosphate as carbon source.B. CQ001 is a bacterium with strong metabolic function and rich metabolic pathways. It has the potential to degrade aromatics and other exogenous chemicals and contains genes for steroid metabolism. Our study enriches the genetic information of Burkholderia and provides information for the application of Burkholderia in bioremediation and steroid medicine production.
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Han D, Gu X, Gao J, Wang Z, Liu G, Barkema HW, Han B. Chlorogenic acid promotes the Nrf2/HO-1 anti-oxidative pathway by activating p21 Waf1/Cip1 to resist dexamethasone-induced apoptosis in osteoblastic cells. Free Radic Biol Med 2019; 137:1-12. [PMID: 31004750 DOI: 10.1016/j.freeradbiomed.2019.04.014] [Citation(s) in RCA: 84] [Impact Index Per Article: 16.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/27/2019] [Revised: 03/19/2019] [Accepted: 04/13/2019] [Indexed: 01/08/2023]
Abstract
In a previous study, p21Waf1/Cip1 (p21) promoted activation of the nuclear factor E2-related factor 2 (Nrf2)/heme oxygenase-1 (HO-1) pathway, which has an important role in regulating apoptosis triggered by oxidative stress and inhibiting development of osteoporosis. Chlorogenic acid (CGA) has a strong protective effect on osteoporosis, closely related to activating the Nrf2/HO-1 pathway. However, whether CGA can resist apoptosis by regulating p21 and consequently promote activation of the Nrf2/HO-1 pathway needs further investigation. MC3T3-E1 cells were treated with dexamethasone (Dex), with or without CGA pre-treatment. Cell proliferation and cytotoxicity were measured using MTT assay and LDH release assay, respectively, and apoptosis assessed by flow cytometry. CGA significantly attenuated mitochondrial apoptosis and reversed down-regulation of p21 in osteoblastic MC3T3-E1 cells exposed to Dex. Additionally, CGA decreased Keap1 expression and promoted activation of the Nrf2/HO-1 pathway, quenching intracellular reactive oxygen species (ROS), hydrogen peroxide (H2O2) and mitochondrial superoxide overproduction boosted by Dex. Importantly, depletion of p21 by siRNA blocked activation of the Nrf2/HO-1 pathway, enhanced oxidative stress and increased apoptosis induced by CGA in MC3T3-E1 cells challenged with Dex. Therefore, CGA promoted the Nrf2/HO-1 anti-oxidative pathway by activating p21 to prevent Dex-induced mitochondrial apoptosis in osteoblastic cells. This pathway has potential as a therapeutic target for prevention and treatment of osteoporosis.
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Kleber C, Lienkamp K, Rühe J, Asplund M. Electrochemically Controlled Drug Release from a Conducting Polymer Hydrogel (PDMAAp/PEDOT) for Local Therapy and Bioelectronics. Adv Healthc Mater 2019; 8:e1801488. [PMID: 30835957 DOI: 10.1002/adhm.201801488] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2018] [Revised: 02/05/2019] [Indexed: 12/27/2022]
Abstract
In this study, the release of fluorescein from a photo-crosslinked conducting polymer hydrogel made from a hydrogel precursor poly(dimethylacrylamide-co-4-methacryloyloxy benzophenone (5%)-co-4-styrenesulfonate (2.5%)) (PDMAAp) and the conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) is investigated. Fluorescein, here used as a model for a drug, is actively released through application of an electrical trigger signal. The detected quantity is more than six times higher in comparison to that released from a conventional PEDOT/polysterene sulfonate (PSS) system. Release profiles, drug dose, and timing can be tailored by the application of different trigger signals and pretreatments. To demonstrate that the novel drug release system can be used for a drug relevant for local delivery to a neural interface, experiments are furthermore performed with the anti-inflammatory drug dexamethasone (Dex). The conducting polymer hydrogel facilitates the active release of Dex, in comparison to the previously used PEDOT/Dex. It is suggested that PEDOT/PDMAAp is an interesting alternative for conducting polymer based drug release systems, with the potential to offer more volume for storage, yet retaining the excellent electrochemical properties known for PEDOT electrodes.
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Stefani RM, Halder SS, Estell EG, Lee AJ, Silverstein AM, Sobczak E, Chahine NO, Ateshian GA, Shah RP, Hung CT. A Functional Tissue-Engineered Synovium Model to Study Osteoarthritis Progression and Treatment. Tissue Eng Part A 2019; 25:538-553. [PMID: 30203722 PMCID: PMC6482911 DOI: 10.1089/ten.tea.2018.0142] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2018] [Accepted: 08/31/2018] [Indexed: 01/15/2023] Open
Abstract
IMPACT STATEMENT The synovium envelops the diarthrodial joint and plays a key regulatory role in defining the composition of the synovial fluid through filtration and biosynthesis of critical boundary lubricants. Synovium changes often precede cartilage damage in osteoarthritis. We describe a novel in vitro tissue engineered model, validated against native synovium explants, to investigate the structure-function of synovium through quantitative solute transport measures. Synovium was evaluated in the presence of a proinflammatory cytokine, interleukin-1, or the clinically relevant corticosteroid, dexamethasone. We anticipate that a better understanding of synovium transport would support efforts to develop more effective strategies aimed at restoring joint health.
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Zhao Y, Wei C, Chen X, Liu J, Yu Q, Liu Y, Liu J. Drug Delivery System Based on Near-Infrared Light-Responsive Molybdenum Disulfide Nanosheets Controls the High-Efficiency Release of Dexamethasone To Inhibit Inflammation and Treat Osteoarthritis. ACS APPLIED MATERIALS & INTERFACES 2019; 11:11587-11601. [PMID: 30844228 DOI: 10.1021/acsami.8b20372] [Citation(s) in RCA: 72] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Intra-articular injection has unique advantages in the treatment of osteoarthritis (OA), although it risks rapid clearance of the therapeutic drugs in the joint cavity. Combining therapeutic agents with functionalized nanocarriers may provide an effective solution. Controlling the therapeutic concentration of the drug in the joint cavity through the drug-loading nanosystem can synergistically treat OA. Here, we proposed an intra-articular drug delivery nanosystem MoS2@CS@Dex (MCD), using the chitosan (CS)-modified molybdenum disulfide (MoS2) nanosheets as near-infrared (NIR) photo-responsive carriers, loaded with the anti-inflammatory drug dexamethasone (Dex). MCD responded to NIR light both in vitro and in vivo and triggered Dex release through photothermal conversion. This enabled the remote-controlled Dex release in the joint cavity by adjusting the radiation behavior of the NIR light. MCD prolonged the residence time of Dex in the joint cavity. The intra-articular injection of MCD in combination with NIR radiation ensured a significant increase in the therapeutic effect of Dex at low systemic doses, which attenuated the cartilage erosion in the OA caused by the secretion of inflammatory factors including TNF-α and IL-1β. The toxicity and side effects on other internal organs during metabolism were reduced in the body. In addition, the photoacoustic imaging capability of MoS2 nanosheets was used to detect the metabolism of MCD in the joint cavity. Our research indicated that MCD has great potential to treat OA.
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Rainville JR, Weiss GL, Evanson N, Herman JP, Vasudevan N, Tasker JG. Membrane-initiated nuclear trafficking of the glucocorticoid receptor in hypothalamic neurons. Steroids 2019; 142:55-64. [PMID: 29242167 PMCID: PMC5997511 DOI: 10.1016/j.steroids.2017.12.005] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Revised: 10/10/2017] [Accepted: 12/07/2017] [Indexed: 11/15/2022]
Abstract
Glucocorticoid binding to the intracellular glucocorticoid receptor (GR) stimulates the translocation of the GR from the cytosol to the nucleus, which leads to the transactivation or transrepression of gene transcription. However, multiple lines of evidence suggest that glucocorticoid signaling can also be initiated from the plasma membrane. Here, we provide evidence for membrane-initiated glucocorticoid signaling by a membrane-impermeant dexamethasone-bovine serum albumin (Dex-BSA) conjugate, which induced GR nuclear trafficking in hypothalamic neurons in vitro and in vivo. The GR nuclear translocation induced by a membrane-impermeant glucocorticoid suggests trafficking of an unliganded GR. The membrane-initiated GR trafficking was not blocked by inhibiting ERK MAPK, p38 MAPK, PKA, Akt, Src kinase, or calcium signaling, but was inhibited by Akt activation. Short-term exposure of hypothalamic neurons to dexamethasone (Dex) activated the glucocorticoid response element (GRE), suggesting transcriptional transactivation, whereas exposure to the Dex-BSA conjugate failed to activate the GRE, suggesting differential transcriptional activity of the liganded compared to the unliganded GR. Microarray analysis revealed divergent transcriptional regulation by Dex-BSA compared to Dex. Together, our data suggest that signaling from a putative membrane glucocorticoid receptor induces the trafficking of unliganded GR to the nucleus, which elicits a pattern of gene transcription that differs from that of the liganded receptor. The differential transcriptional signaling by liganded and unliganded receptors may contribute to the broad range of genetic regulation by glucocorticoids, and may help explain some of the different off-target actions of glucocorticoid drugs.
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Li S, Zeng YC, Peng K, Liu C, Zhang ZR, Zhang L. Design and evaluation of glomerulus mesangium-targeted PEG-PLGA nanoparticles loaded with dexamethasone acetate. Acta Pharmacol Sin 2019; 40:143-150. [PMID: 29950614 PMCID: PMC6318296 DOI: 10.1038/s41401-018-0052-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2018] [Accepted: 05/20/2018] [Indexed: 12/20/2022] Open
Abstract
Mesangial proliferative glomerulonephritis (MsPGN), one of the most common glomerulonephritis pathological types, often leads to end-stage renal disease over a prolonged period. But the current treatment of MsPGN is non-specific and causes serious side effects, thus novel therapeutics and targeting strategies are urgently demanded. By combining the advantages of PEG-PLGA nanoparticles and the size selection mechanism of renal glomerulus, we designed and developed a novel PEG-PLGA nanoparticle delivery system capable of delivering dexamethasone acetate (A-DEX) into glomerular mesangium. We determined that 90 nm was the optimum size to encapsulate A-DEX for glomerular mesangium targeting based on the size-selection mechanism of glomerulus. After intravenous administration in rats, 90 nm DiD-loaded NPs were found to accumulate to a greater extent in the kidney and kidney cortex compared with the free DiD solution. The 90 nm A-DEX NPs are also more stable at room temperature and showed a sustained release pattern. In rat glomerular mesangial cells (HBZY-1) in vitro, we found that the uptake of 90 nm A-DEX NPs was both temperature-dependent and energe-dependent, and they were mostly engulfed via clathrin-dependent endocytosis pathways. In summary, we have successfully developed a glomerular mesangium-targeted PEG-PLGA NPs, which is potential for the treatment of MsPGN.
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Hurtado MD, Cortes T, Natt N, Young WF, Bancos I. Extensive clinical experience: Hypothalamic-pituitary-adrenal axis recovery after adrenalectomy for corticotropin-independent cortisol excess. Clin Endocrinol (Oxf) 2018; 89:721-733. [PMID: 29968420 PMCID: PMC6246804 DOI: 10.1111/cen.13803] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/06/2018] [Revised: 06/28/2018] [Accepted: 06/29/2018] [Indexed: 12/26/2022]
Abstract
OBJECTIVE To identify predictors of hypothalamic-pituitary-adrenal (HPA) axis recovery interval and severity of glucocorticoid withdrawal symptoms (GWS) in patients undergoing adrenalectomy for corticotropin-independent cortisol excess. DESIGN This is a retrospective study of patients with mild autonomous cortisol excess (MACE), moderate and severe Cushing syndrome (CS) who developed adrenal insufficiency after unilateral adrenalectomy between 1998 and 2017. RESULTS Adrenalectomy was performed in 81 patients (79% women, median age 52 years [IQR 42-62]). HPA axis recovery occurred at a median of 4.3 months (IQR 1.6-11.4) after adrenalectomy (severe CS vs moderate CS vs MACE: median 11.4 vs 2.8 vs 2.1 months, P < 0.01). Main predictors of HPA axis recovery interval included: preoperative serum cortisol concentration after 1-mg overnight dexamethasone suppression test >10 μg/dL or >276 nmol/L (9.7 vs 1.3 months if cortisol ≤10 μg/dL or ≤276 nmol/L, P < 0.01); body mass index (for every 3 kg/m2 decrease, glucocorticoid taper increased by 1 month, P < 0.05); age <45 (11.4 vs 2.3 months if ≥45 years, P < 0.05); duration of symptoms prior to diagnosis >1 year (11.4 vs 2.8 months if ≤1 year); moon facies (11.4 vs 2.2 months if no rounding of the face); and myopathy (13.1 vs 2.7 months if no myopathy, P < 0.05). Patients with severe CS had a higher incidence of GWS compared to patients with MACE (66.7% vs 40.0%, P < 0.05) with a median of 1 and 0 events/patient, respectively. CONCLUSIONS The HPA axis recovery interval was the longest for patients with severe CS. Surprisingly, patients with moderate CS recovered their HPA axis as quickly as those with MACE. Glucocorticoid withdrawal symptoms were observed in all groups, with more events in patients with severe CS. This study emphasizes the need to counsel patients on expectations for HPA axis recovery and address intervention for GWS based on individual preoperative parameters.
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Warther D, Xiao Y, Li F, Wang Y, Huffman K, Freeman WR, Sailor M, Cheng L. Porous silicon based intravitreal platform for dual-drug loading and controlled release towards synergistic therapy. Drug Deliv 2018; 25:1537-1545. [PMID: 29996687 PMCID: PMC6058705 DOI: 10.1080/10717544.2018.1486474] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2018] [Revised: 05/30/2018] [Accepted: 06/05/2018] [Indexed: 01/28/2023] Open
Abstract
The number of blind and low vision persons in the US is projected to increase to 5.68 million by 2020. The eye diseases causing loss of vision are life-long, chronic, and often need protracted presence of therapeutics at the disease site to keep the disease in remission. In addition, multiple pathologies participate in the disease process and a single therapy seems insufficient to bring the disease under control and prevent vision loss. This study demonstrates the use of porous silicon (pSi) particles sequentially loaded with daunorubicin (DNR) and dexamethasone (DEX) to create a synergistic intravitreally injectable dual-drug delivery system. DEX targets chronic inflammation while DNR inhibits excessive cell proliferation as well as suppresses hypoxia-inducible factor 1 to reduce scarring. This pSi-based delivery system releases therapeutic concentrations of DNR for 100 days and DEX for over 165 days after a single dose. This intravitreal dual-drug delivery system is also well tolerated after injection into the rabbit eye model, attested by ocular biomicroscopy, ocular tonometry, electroretinography, and histology. This novel dual-drug delivery system opens an attractive modality for combination therapy to manage refractory chorioretinal diseases and further preclinical studies are warranted to evaluate its efficacy.
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Song X, Jiao H, Zhao J, Wang X, Lin H. Dexamethasone and insulin stimulate ghrelin secretion of broilers in a different way. Gen Comp Endocrinol 2018; 268:14-21. [PMID: 30016627 DOI: 10.1016/j.ygcen.2018.07.009] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Revised: 07/06/2018] [Accepted: 07/13/2018] [Indexed: 12/27/2022]
Abstract
Ghrelin is one of the most important appetite regulating peptides, involved in the regulation of energy homeostasis. The role of ghrelin on the appetite and fat metabolism in chickens is different from that of ghrelin in mammals. Glucocorticoids and insulin are important hormones and work differently in energy regulation of body. In this study, the effects of dexamethasone (DEX, 2.0 mg/kg BW), subcutaneous insulin injection (40 µg/kg BW), and glucose load on ghrelin secretion and expression were determined in broilers. DEX treatment increased circulating ghrelin concentration in broiler fed with either a low-energy diet (11.05 MJ/kg of metabolizable energy) or a high-energy diet (14.44 MJ/kg of metabolizable energy). The expression levels of ghrelin were increased while both ghrelin and its receptor GHS-R1a expression levels were stimulated by DEX. A single subcutaneous insulin injection (40 µg/kg BW) or oral glucose infusion (2 g/kg BW) rise circulating ghrelin level. Ghrelin expression in the proventriculus was increased by insulin treatment but unchanged by glucose load. DEX had no detectable influence on ghrelin and GHS-R1a expression in the hypohtalamus, whereas insulin suppressed their expression. In conclusion, both insulin and glucocorticoid stimulate ghrelin secretion in chickens, in contrast to mammals. Glucocorticoids evoke peripheral ghrelin/GHS-R1a system while insulin increases peripheral ghrelin expression and suppress the activation of central ghrelin/GHS-R1a system. The result suggests that ghrelin involved in the modulating network of energy homeostasis in concert with glucocorticoids and insulin.
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Tang W, Zhao Z, Chong Y, Wu C, Liu Q, Yang J, Zhou R, Lian ZX, Liang G. Tandem Enzymatic Self-Assembly and Slow Release of Dexamethasone Enhances Its Antihepatic Fibrosis Effect. ACS NANO 2018; 12:9966-9973. [PMID: 30285414 DOI: 10.1021/acsnano.8b04143] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Many chronic liver diseases will advance to hepatic fibrosis and, if without timely intervention, liver cirrhosis or even hepatocellular carcinoma. Anti-inflammation could be a standard therapeutic strategy for hepatic fibrosis treatment, but a "smart" strategy of hepatic fibrosis-targeted, either self-assembly or slow release of an anti-inflammation drug ( e.g., dexamethasone, Dex), has not been reported. Herein, we rationally designed a hydrogelator precursor Nap-Phe-Phe-Lys(Dex)-Tyr(H2PO3)-OH (1-Dex-P) and proposed a tandem enzymatic strategy of self-assembly and slow release of Dex, with which the precursor exhibited much stronger antihepatic fibrosis effect than Dex both in vitro and in vivo. Enzymatic and cell experiments validated that 1-Dex-P was first dephosphorylated by alkaline phosphatase to yield Nap-Phe-Phe-Lys(Dex)-Tyr-OH (1-Dex), which self-assembled into nanofiber 1-Dex. The nanofiber was then hydrolyzed by esterase to transform into nanofiber 1, accompanied by slow release of Dex. We anticipate that our "smart" tandem enzymatic strategy could be widely employed to design more sophisticated drug delivery systems to achieve enhanced therapeutic efficacy than free drugs in the future.
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Capes-Davis A, Andrew SD, Hyland VJ, Twigg S, Learoyd DL, Dwight T, Marsh DJ, Robinson BG. Glucocorticoids differentially inhibit expression of the RET proto-oncogene. Gene Expr 2018; 8:311-26. [PMID: 10947080 PMCID: PMC6157381] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
The RET proto-oncogene encodes a receptor tyrosine kinase activated by the binding of factors from the glial cell line-derived neurotrophic factor (GDNF) family to receptor-alpha components such as GDNF family receptor alpha-1 (GFR alpha-1). Mutations within the sequence of the RET proto-oncogene are associated with multiple endocrine neoplasia type 2 (MEN 2), an inherited tumor syndrome characterized by the development of medullary thyroid carcinoma (MTC) and other neuroendocrine tumors. Despite Northern analysis showing that RET is expressed in the majority of MTCs, the factors regulating this expression are poorly understood. To address this issue we examined RET expression in response to glucocorticoids in the TT cell line, derived from a metastatic MTC. The synthetic glucocorticoid dexamethasone was found to reduce RET expression at both mRNA and protein levels. This effect was dose responsive and maximal at 24 h. The reduction in RET mRNA was shown to be specific to glucocorticoids and was also seen in a primary MTC culture. Nuclear run-on studies revealed the reduction in steady-state RNA to be due to a decrease in RET mRNA transcription and the effect was shown to be independent of new protein synthesis or RNA stability. Dexamethasone was also found to exert an inhibitory effect upon cell growth, suggesting a potential use for glucocorticoids in the treatment of medullary carcinoma and MEN 2.
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Whirledge SD, Kisanga EP, Oakley RH, Cidlowski JA. Neonatal Genistein Exposure and Glucocorticoid Signaling in the Adult Mouse Uterus. ENVIRONMENTAL HEALTH PERSPECTIVES 2018; 126:047002. [PMID: 29624291 PMCID: PMC6071733 DOI: 10.1289/ehp1575] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/05/2017] [Revised: 02/05/2018] [Accepted: 02/13/2018] [Indexed: 06/08/2023]
Abstract
BACKGROUND Female reproductive tract development is sensitive to the endocrine-disrupting potential of environmental estrogens. Early-life exposure to the dietary phytoestrogen genistein impairs fertility and persistently alters the transcriptome in the oviduct and uterus of rodents. Glucocorticoid signaling, which has recently been shown to be essential for normal fertility in the female mouse uterus, is antagonized by genistein. OBJECTIVE Our goal was to determine whether early-life exposure to genistein disrupts glucocorticoid signaling in the mouse uterus, which may contribute to infertility. METHODS Female C57Bl/6 mice were exposed to either 50 mg/kg per day genistein, 10 μg/kg per day estradiol, or vehicle (corn oil) on postnatal days 1-5 (PND1-5), and then treated with the synthetic glucocorticoid dexamethasone (Dex: 1 mg/kg) or vehicle (saline) on PND5, at weaning on PND21, or as adults on PND56 following adrenalectomy and ovariectomy to evaluate glucocorticoid responsiveness. Uteri were isolated following treatment for gene expression or chromatin immunoprecipitation. RESULTS Neonatal exposure to genistein altered the uterine transcriptome of adult mice and caused substantial changes to the transcriptional response to glucocorticoids. Although expression of the glucocorticoid receptor was not affected, genistein exposure disrupted glucocorticoid receptor recruitment to specific regulatory sites in target genes. Many genes involved in chromatin remodeling were dysregulated in genistein-exposed mice, suggesting that epigenetic reprograming may contribute to the altered glucocorticoid response of the uterus following early-life exposure to genistein. These changes affected the biological activity of glucocorticoids within the uterus, as glucocorticoids antagonized the proliferative effects of estradiol in the uterus of control mice but not genistein-exposed mice. CONCLUSIONS Our findings suggest that disruption of glucocorticoid signaling due to early-life exposure to environmental estrogens may in part render the uterus unable to support implantation. https://doi.org/10.1289/EHP1575.
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Zhang Y, Yue Y, Chang M. Local anaesthetic pain relief therapy: In vitro and in vivo evaluation of a nanotechnological formulation co-loaded with ropivacaine and dexamethasone. Biomed Pharmacother 2017; 96:443-449. [PMID: 29031203 DOI: 10.1016/j.biopha.2017.09.124] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 09/24/2017] [Accepted: 09/24/2017] [Indexed: 12/22/2022] Open
Abstract
Combination therapy is frequently applied to anesthesia and analgesia for its benefits, which includes prolonged analgesia following peripheral nerve blockade, and reduced side effects. The aim of this study was to develop chitosan (CH) coated poly(ε-caprolactone) (PCL) nanoparticles to co-deliver ropivacaine (RPV) and dexamethasone (DEM) (RPV/DEM CH-PCL NPs) for the prolongation of anesthesia and pain relief. In the present study, RPV/DEM CH-PCL NPs were fabricated. The properties of CH-PCL NPs were evaluated for their particle sizes, zeta potential, drug loading capacity and in vitro drug release profile. In vitro skin permeation and in vivo therapeutic effect in an animal model were further investigated. The results showed that the NPs was around 190nm, with PDI of less than 0.20. The zeta potentials of NPs were about 36mV. In vitro drug release of both RPV and DEM from NPs complied with sustained behaviors. All of the drugs loaded NPs samples studied exhibited no obvious L929 cells cytotoxicity. In vitro skin penetration profiles showed the amount of RPV permeated through the skin from NPs was significantly higher than free RPV. RPV and DEM co-loaded NPs induced remarkably better anesthetic effect than non DEM loaded RPV CH-PCL NPs. The results suggested that adding a small dosage of DEM could improve the anesthesia efficacy of RVP to a large content. The resulting formulation could be applied as a promising anesthesia system for local anesthetics therapy.
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Huang X, Liu S, Yang Y, Duan Y, Lin D. Controllable continuous sub-tenon drug delivery of dexamethasone disodium phosphate to ocular posterior segment in rabbit. Drug Deliv 2017; 24:452-458. [PMID: 28165816 PMCID: PMC8241022 DOI: 10.1080/10717544.2016.1264498] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2016] [Revised: 11/14/2016] [Accepted: 11/21/2016] [Indexed: 12/16/2022] Open
Abstract
Corticosteroids have been used for treatment of posterior segment eye diseases, but the delivery of drug to the posterior segments is still a problem to resolve. In our study, we explore the feasibility of Sub-tenon's Controllable Continuous Drug Delivery to ocular posterior segment. Controllable continuous sub-tenon drug delivery (CCSDD) system, intravenous injections (IV) and sub-conjunctival injections (SC) were used to deliver dexamethasone disodium phosphate (DEXP) in rabbits, the dexamethasone concentration was measured in the ocular posterior segment tissue by Shimadzu LC-MS 2010 system at different time points in 24 h after first dose injection. Levels of dexamethasone were significantly higher at 12, 24 h in CCSDD than two other approaches, and at 3, 6 h in CCSDD than IV in vitreous body (p < 0.01); at 6, 12, 24 h in CCSDD than two other approaches, and at 1, 3 h in CCSDD than IV in retinal/choroidal compound (p < 0.01); at 3, 6, 12, 24 h in CCSDD than two other approaches, and at 1 h in CCSDD than IV in sclera (p < 0.05). The AUC0-24 in CCSDD group is higher than two other groups in all ocular posterior segment tissue. Our results demonstrated that dexamethasone concentration could be sustained moderately higher in the posterior segment by CCSDD than SC and IV, indicating that CCSDD might be a therapeutic alternative to treat a variety of intractable posterior segment diseases.
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Voon HY, Leong MS, Li CW, Bujang A, Suharjono H. Corticosteroid-induced leukocytosis in pregnancy: A prospective observational study. THE MEDICAL JOURNAL OF MALAYSIA 2017; 72:259-263. [PMID: 29197879] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
BACKGROUND In the course of managing preterm labour, increasing trends of total white cell count raises concern for the obstetrician, suggesting a possible underlying infectious aetiology. Although mild leukocytosis is expected in pregnancy, the patterns of increment after corticosteroid administration are not well described beyond animal models and in a small number of human studies. METHODS Seventy-three consecutive patients who required antenatal corticosteroids for either preterm labour or prelabour caesarean section were recruited and given a standard course of 12mg dexamethasone phosphate, twelve hours apart. Venous blood samples were taken before administration, at six hours and 36 hours after the first dose of dexamethasone. RESULTS The total white count trend was 10.31±2.62 at baseline, 11.44±3.05 at six hours and 12.20±3.49 at 36 hours. Neutrophil-lymphocyte ratio was 3.60±1.31, 8.73±3.63 and 3.24±1.49 respectively, reflecting relative neutrophilia and lymphopenia which normalised by 36 hours. CONCLUSION In contrast to previous studies, we found only a slight increment in total white cell count of about 10%. The marginal changes described in our study would not normally raise any clinical concern, although vigilance should be exercised if higher levels were observed.
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Steenbergen PJ, Bardine N, Sharif F. Kinetics of glucocorticoid exposure in developing zebrafish: A tracer study. CHEMOSPHERE 2017; 183:147-155. [PMID: 28544900 DOI: 10.1016/j.chemosphere.2017.05.059] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2016] [Revised: 05/02/2017] [Accepted: 05/10/2017] [Indexed: 06/07/2023]
Abstract
In the current study the dynamics of glucocorticoid uptake by zebrafish chorionated embryos from the surrounding medium were studied, using 2.5 μM cortisol or dexamethasone solutions complemented with their tritiated variant. We measured the uptake of radioactive cortisol by embryos during a 1 h submersion. Interestingly, the signal in chorionated embryos was 85% (exposure: 1-2 hpf) or 78% (exposure: 48-49 hpf) of the signal present in an equal volume medium. By comparing embryos measured without chorion, we found that 18-20% of the radioactivity present in chorionated embryos is actually bound to the chorion or located in the perivitelline space. Consequently, embryonic tissue contains radioactivity levels of 60% of a similar volume of medium after 1 h incubation. During early developmental stages (1-48 hpf) exposure of more than 24 h in cortisol was needed to achieve radioactivity levels similar to an equal volume of medium within the embryonic tissue and more than 48 h for dexamethasone. In glucocorticoid-free medium, radioactivity dropped rapidly below 10% for both glucocorticoids, suggesting that the major portion of the embryonic radioactivity was a result of simple diffusion. During later developmental stages (48-96 hpf) initial uptake dynamics were similar, but showed a decrease of tissue radioactivity to 20% of an equal volume of medium after hatching, probably due to development and activation of the hypothalamic pituitary interrenal axis. Uptake is dependent on the developmental stage of the embryo. Furthermore, the presence of the chorion during exposure should be taken into account even when small lipophilic molecules are being tested.
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Ueland GÅ, Methlie P, Kellmann R, Bjørgaas M, Åsvold BO, Thorstensen K, Kelp O, Thordarson HB, Mellgren G, Løvås K, Husebye ES. Simultaneous assay of cortisol and dexamethasone improved diagnostic accuracy of the dexamethasone suppression test. Eur J Endocrinol 2017; 176:705-713. [PMID: 28298353 DOI: 10.1530/eje-17-0078] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/30/2017] [Revised: 03/10/2017] [Accepted: 03/15/2017] [Indexed: 11/08/2022]
Abstract
OBJECTIVES The overnight dexamethasone (DXM) suppression test (DST) has high sensitivity, but moderate specificity, for diagnosing hypercortisolism. We have evaluated if simultaneous measurement of S-DXM may correct for variable DXM bioavailability and increase the diagnostic performance of DST, and if saliva (sa) is a feasible adjunct or alternative to serum. DESIGN AND METHODS Prospective study of DST was carried out in patients with suspected Cushing's syndrome (CS) (n = 49), incidentaloma (n = 152) and healthy controls (n = 101). Cortisol, cortisone and DXM were assayed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). RESULTS Three hundred and two subjects underwent DST; S-cortisol was ≥50 nmol/L in 83 patients, of whom 11 had CS and 27 had autonomous cortisol secretion. The lower 2.5 percentile of S-DXM in subjects with negative DST (n = 208) was 3.3 nmol/L, which was selected as the DXM cut-off level. Nine patients had the combination of low S-DXM and positive DST. Of these, three had been misdiagnosed as having autonomous cortisol secretion. DST results were highly reproducible and confirmed in a replication cohort (n = 58). Patients with overt CS had significantly elevated post-DST sa-cortisol and sa-cortisone levels compared with controls; 23 of 25 with autonomous cortisol secretion had elevated sa-cortisone and 14 had elevated sa-cortisol. CONCLUSIONS Simultaneous measurement of serum DXM and cortisol reduced false-positive DSTs by 20% and improved the specificity. S-DXM >3.3 nmol/L is sufficient for the suppression of cortisol <50 nmol/L. Measurement of glucocorticoids in saliva is a non-invasive and easy procedure and post-DST sa-cortisone was found particularly useful in the diagnosis of CS.
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Hu JB, Kang XQ, Liang J, Wang XJ, Xu XL, Yang P, Ying XY, Jiang SP, Du YZ. E-selectin-targeted Sialic Acid-PEG-dexamethasone Micelles for Enhanced Anti-Inflammatory Efficacy for Acute Kidney Injury. Theranostics 2017; 7:2204-2219. [PMID: 28740545 PMCID: PMC5505054 DOI: 10.7150/thno.19571] [Citation(s) in RCA: 44] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2017] [Accepted: 03/16/2017] [Indexed: 12/12/2022] Open
Abstract
The effective treatment for acute kidney injury (AKI) is currently limited, and care is primarily supportive. Sialic acid (SA) is main component of Sialyl Lewisx antigen on the mammalian cell surface, which participates in E-selectin binding. Therefore, dexamethasone(DXM)-loaded E-selectin-targeting sialic acid-polyethylene glycol-dexamethasone (SA-PEG-DXM/DXM) conjugate micelles are designed for ameliorating AKI. The conjugates are synthesized via the esterification reaction between PEG and SA or DXM, and can spontaneously form micelles in an aqueous solution with a 65.6 µg/mL critical micelle concentration. Free DXM is incorporated into the micelles with 6.28 ± 0.21% drug loading content. In vitro DXM release from SA-PEG-DXM/DXM micelles can be prolonged to 48h. Much more SA-PEG-DXM micelles can be internalized by lipopolysaccharide (LPS)-activated human umbilical vein endothelial cells (HUVECs) in comparison to PEG-DXM micelles due to specific interaction between SA and E-selectin expressed on HUVECs, and consequently more SA-PEG-DXM micelles are accumulated in the kidney of AKI murine model. Furthermore, SA in SA-PEG-DXM conjugates can significantly ameliorate LPS-induced production of pro-inflammatory cytokines via suppressing LPS-activated Beclin-1/Atg5-Atg12-mediated autophagy to attenuate toxicity. Compared with free DXM and PEG-DXM/DXM micelles, SA-PEG-DXM/DXM micelles show better therapeutical effects, as reflected by the improved renal function, histopathological changes, pro-inflammatory cytokines, oxidative stress and expression of apoptotic related proteins.
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Enjapoori AK, Lefèvre CM, Nicholas KR, Sharp JA. Hormonal regulation of platypus Beta-lactoglobulin and monotreme lactation protein genes. Gen Comp Endocrinol 2017; 242:38-48. [PMID: 26673872 DOI: 10.1016/j.ygcen.2015.12.005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2015] [Revised: 11/27/2015] [Accepted: 12/04/2015] [Indexed: 12/16/2022]
Abstract
Endocrine regulation of milk protein gene expression in marsupials and eutherians is well studied. However, the evolution of this complex regulation that began with monotremes is unknown. Monotremes represent the oldest lineage of extant mammals and the endocrine regulation of lactation in these mammals has not been investigated. Here we characterised the proximal promoter and hormonal regulation of two platypus milk protein genes, Beta-lactoglobulin (BLG), a whey protein and monotreme lactation protein (MLP), a monotreme specific milk protein, using in vitro reporter assays and a bovine mammary epithelial cell line (BME-UV1). Insulin and dexamethasone alone provided partial induction of MLP, while the combination of insulin, dexamethasone and prolactin was required for maximal induction. Partial induction of BLG was achieved by insulin, dexamethasone and prolactin alone, with maximal induction using all three hormones. Platypus MLP and BLG core promoter regions comprised transcription factor binding sites (e.g. STAT5, NF-1 and C/EBPα) that were conserved in marsupial and eutherian lineages that regulate caseins and whey protein gene expression. Our analysis suggests that insulin, dexamethasone and/or prolactin alone can regulate the platypus MLP and BLG gene expression, unlike those of therian lineage. The induction of platypus milk protein genes by lactogenic hormones suggests they originated before the divergence of marsupial and eutherians.
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Austdal LPE, Bjørnstad S, Mathisen GH, Aden PK, Mikkola I, Paulsen RE, Rakkestad KE. Glucocorticoid Effects on Cerebellar Development in a Chicken Embryo Model: Exploring Changes in PAX6 and Metalloproteinase-9 After Exposure to Dexamethasone. J Neuroendocrinol 2016; 28. [PMID: 27791298 DOI: 10.1111/jne.12438] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/31/2016] [Revised: 10/25/2016] [Accepted: 10/25/2016] [Indexed: 12/22/2022]
Abstract
The developing cerebellum is vulnerable to effects of glucocorticoids and cerebellar dysfunction is associated with neurodevelopmental disorders (e.g. autism). Transcription factor PAX6 and matrix metalloproteinase-9 (MMP-9) are critical for normal cerebellar development and are highly expressed in migrating neurones. Alterations in MMP-9 and PAX6 are associated with altered cerebellar development. In the present study, we characterised the growth rate and development of the cortical layers, and further investigated how the levels of PAX6 and MMP-9, as well as glucocorticoid receptor (GR) and proliferating cell nuclear antigen (PCNA), change in the cerebellum during the foetal period [embryonic day (E)12-21] in chicken, which corresponds to the human perinatal period. Dexamethasone (DEX) was administered in ovo at E13 and E16, aiming to investigate how prenatal exposure to glucocorticoids interferes with normal development. DEX reduced foetal and cerebellar weight at E17 in a dose-dependent manner linked to a reduced level of PCNA and, over time, down-regulation of GR. We report that promoter activity of PAX6 and MMP-9 increased as a result of GR-stimulation in vitro. Prenatal DEX increased the protein level of PAX6 in a transient manner. PAX6 is reduced in mature granule neurones, and this occurred earlier in embryos exposed to DEX than in non-exposed controls. DEX exposure also led to a slow-onset down-regulation of MMP-9. Taken together, these findings indicate that excess prenatal glucocorticoid stimulation disturbs normal development of the cerebellum through mechanisms associated with reduced proliferation and accelerated maturation where PAX6 and MMP-9 play important roles.
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