Synthetic Corticosteroid Research Articles

Thyroïdites : où en est-on en 2019 ?

Thyroiditis is a frequent and mostly benign disease that can sometimes disrupt the thyroid balance. Their diagnosis, as well as their aetiology, is a necessary step in the management of the patients. Painful thyroiditis includes acute thyroiditis of infectious origin and subacute thyroiditis. The first one can be treated by antibiotics or antifungals depending on the germ found. The second one will be treated with non-steroidal anti-inflammatory drugs or corticosteroids. In cases of Hashimoto's thyroiditis with overt hypothyroidism, replacement therapy with L-thyroxine will be adapted to the TSH level. As amiodarone treatment provides dysthyroidism, the thyroid status should be monitored regularly. Hypothyroidism will be treated using thyroid replacement therapy. Hyperthyroidism imposes a stop of amiodarone when it is possible. Treatment with synthetic antithyroid drugs (propyl-thio-uracil) or corticosteroids could be used whether there is an underlying thyroid disease or not. Immunotherapies with anti-PD-1/PDL1 or anti-CTLA-4 can also provide dysthyroidism. A monitoring of the thyroid assessment needs to be done in these patients, even if there are no clinical signs, which are not very specific in this context. The treatment of hypothyroidism will be based on thyroid replacement therapy according to the TSH level and the presence or absence of anti-TPO antibodies. Treatment of symptomatic hyperthyroidism may involve a prescription of beta-blockers, or synthetic antithyroid drugs in case of positive anti-TSH receptor antibodies. In all cases, it is desirable to contact an endocrinologist to confirm the diagnosis hypothesis and to decide on a suitable treatment.

Two Pioneer Transcription Factors, Krüppel-Like Transcription Factor 4 and Glucocorticoid Receptor, Cooperatively Transactivate the Bovine Herpesvirus 1 ICP0 Early Promoter and Stimulate Productive Infection.

An important site for bovine herpesvirus 1 (BoHV-1) latency is sensory neurons within trigeminal ganglia (TG). The synthetic corticosteroid dexamethasone consistently induces BoHV-1 reactivation from latency. Expression of four Krüppel-like transcription factors (KLF), i.e., KLF4, KLF6, PLZF (promyelocytic leukemia zinc finger), and KLF15, are induced in TG neurons early during dexamethasone-induced reactivation. The glucocorticoid receptor (GR) and KLF15 form a feed-forward transcription loop that cooperatively transactivates the BoHV-1 immediate early transcription unit 1 (IEtu1) promoter that drives bovine infected cell protein 0 (bICP0) and bICP4 expression. Since the bICP0 gene also contains a separate early (E) promoter, we tested the hypothesis that GR and KLF family members transactivate the bICP0 E promoter. GR and KLF4, both pioneer transcription factors, cooperated to stimulate bICP0 E promoter activity in a ligand-independent manner in mouse neuroblastoma cells (Neuro-2A). Furthermore, GR and KLF4 stimulated productive infection. Mutating both half GR binding sites did not significantly reduce GR- and KLF4-mediated transactivation of the bICP0 E promoter, suggesting that a novel mechanism exists for transactivation. GR and KLF15 cooperatively stimulated bICP0 activity less efficiently than GR and KL4: however, KLF6, PLZF, and GR had little effect on the bICP0 E promoter. GR, KLF4, and KLF15 occupied bICP0 E promoter sequences in transfected Neuro-2A cells. GR and KLF15, but not KLF4, occupied the bICP0 E promoter at late times during productive infection of bovine cells. Collectively, these studies suggest that cooperative transactivation of the bICP0 E promoter by two pioneer transcription factors (GR and KLF4) correlates with stimulating lytic cycle viral gene expression following stressful stimuli.IMPORTANCE Bovine herpesvirus 1 (BoHV-1), an important bovine pathogen, establishes lifelong latency in sensory neurons. Reactivation from latency is consistently induced by the synthetic corticosteroid dexamethasone. We predict that increased corticosteroid levels activate the glucocorticoid receptor (GR). Consequently, viral gene expression is stimulated by the activated GR. The immediate early transcription unit 1 promoter (IEtu1) drives expression of two viral transcriptional regulatory proteins, bovine infected cell protein 0 (bICP0) and bICP4. Interestingly, a separate early promoter also drives bICP0 expression. Two pioneer transcription factors, GR and Krüppel-like transcription factor 4 (KLF4), cooperatively transactivate the bICP0 early (E) promoter. GR and KLF15 cooperate to stimulate bICP0 E promoter activity but significantly less than GR and KLF4. The bICP0 E promoter contains enhancer-like domains necessary for GR- and KLF4-mediated transactivation that are distinct from those for GR and KLF15. Stress-induced pioneer transcription factors are proposed to activate key viral promoters, including the bICP0 E promoter, during early stages of reactivation from latency.

Immunosuppressive and immunomodulatory therapies for neuromuscular diseases. Part I: Traditional agents.

Immunosuppressive and immunomodulatory therapies have had a major effect on the treatment of immune-mediated neuromuscular diseases. After the landmark introduction of synthetic corticosteroids, other therapies have become available, including plasma exchange (PLEX), immunoglobulin G (IgG), and steroid-sparing immunosuppressive drugs. More recently, novel biologically derived and antigen-specific pharmaceuticals have entered neuromuscular practice. Various levels of evidence guide the use of these treatments. This article reviews current immune-based therapies in neuromuscular diseases and is divided into two parts. Part I provides an update on the evidence and use of traditional therapies, such as corticosteroids, PLEX, intravenously delivered IgG (IVIG), and steroid-sparing immunosuppressive drugs. Part II focuses on the recently US Food and Drug Administration-approved therapies eculizumab and subcutaneous IgG (SCIG), the current indications for rituximab in neuromuscular disease, and on novel immunosuppressive therapeutic approaches under development.

Progesterone increases the incidence of bovine herpesvirus 1 reactivation from latency and stimulates productive infection

Bovine herpesvirus 1 (BoHV-1), including modified live vaccines, can cause abortions in pregnant cows. Progesterone maintains pregnancy and promotes spermiogenesis and testosterone biosynthesis in males: furthermore, progesterone is a neuro-steroid. Recent published studies demonstrated progesterone stimulated the BoHV-1 immediate early transcription unit 1 (IEtu1) promoter, and two glucocorticoid receptor response elements within the promoter were required for progesterone mediated transactivation. In this study, we tested whether progesterone induces reactivation from latency in rabbits. As expected, the synthetic corticosteroid dexamethasone consistently induced reactivation from latency in males and females. While progesterone induced reactivation from latency in approximately one-half of male rabbits, virus shedding was sporadic compared to dexamethasone and less efficient in female rabbits. Progesterone significantly increased productive infection in rabbit skin cells, which correlated with stimulating reactivation. These studies suggest progesterone promotes BoHV-1 spread in cattle, in part, by increasing the frequency of reactivation from latency.

Beclomethasone dipropionate in microscopic colitis: Results of an exploratory open-label multicentre study (COLCO).

Budesonide has been proven to be an effective treatment for microscopic colitis (MC). However, the two current commercially available preparations are released in the ileum. Beclomethasone dipropionate (Clipper®) is a synthetic corticosteroid with topical colonic release. This study aimed to explore whether an open-label treatment with beclomethasone dipropionate is an effective treatment for MC. Prospectively collected data of 30 patients from six centres were retrospectively analysed. All patients had a confirmed diagnosis of idiopathic MC (lymphocytic and collagenous colitis) and were symptomatic (i.e. ≥ 21 loose stools over a seven-day period). Treatment consisted of 10 mg beclomethasone daily for four weeks, followed by 5 mg daily for another four weeks. The primary end point was the proportion of patients in remission (i.e. a mean of < 3 stools/day and a mean of <1 watery stool per day) after an eight-week treatment period. Secondary end points were the proportion of patients responding to therapy at weeks 4 and 8, remission at weeks 4 and 12 and relapse at week 12. Reported adverse events were collected. Overall, at week 8, remission was achieved in 70%, and 77% of patients were responding to treatment. After four weeks of treatment, 80% were responding, and 67% were in remission. Four weeks after stopping treatment, 60% were still in remission. This open-label study suggests that an eight-week course of beclomethasone could be a promising and relatively safe treatment for MC. A randomised controlled study is warranted.

Effects of truck transportation and slaughtering on the occurrence of prednisolone and its metabolites in cow urine, liver, and adrenal glands

BackgroundThe recognition of illegal administration of synthetic corticosteroids in animal husbandry has been recently challenged by the case of prednisolone, whose occasional presence in the urine of bovines under strong stressful conditions was attributed to endogenous biosynthesis, not to exogenous administration. The study of the natural stress sources possibly inducing endogenous prednisolone production represents a stimulating investigation subject. The biochemical effects of transportation and slaughtering were verified in untreated cows by studying the possible occurrence of prednisolone and its metabolites in urine, liver and adrenal glands, and the cortisol/cortisone quantification.ResultsCortisol, cortisone, prednisolone and its metabolites were measured in urine, collected at farm under natural micturition and then at the slaughterhouse. The study was performed on 15 untreated cows reared in different farms at the end of their productive cycle. 2–3 days after the first urine collection, the animals were transported by trucks to the abattoir, slaughtered, and subjected to a second urine sampling from the bladder. Specimens of liver and adrenal gland were also collected and analysed by means of a liquid chromatography-tandem mass spectrometry (LC-MS/MS) validated method. The stressful conditions of transportation and slaughtering proved to increase considerably the urinary levels of cortisol and cortisone as compared to those collected at farm. Prednisolone was detected in the urine collected at the slaughterhouse of two cows only, at a concentration level (≈0.6 μg L− 1) largely below the official cut off (5.0 μg L− 1) established to avoid false non-compliances. These two animals exhibited the highest urinary cortisol levels of the series. Prednisolone and prednisone were also detected in the adrenal glands of a different cow. Prednisolone metabolites were not detected in any urine, liver, and adrenal gland sample.ConclusionWithin the constraints of the condition adopted, this study confirms the sporadic presence of prednisolone traces (2 samples out of 15) and the consistently increased concentration of cortisone and cortisol in the urines collected from cows subjected to truck transportation and subsequent slaughtering. No prednisolone metabolites were detected in any liver and adrenal gland samples, nor in urine specimens, unlike what was previously reported for cows artificially stressed by pharmacological treatment.

Effect of Prednisolone on the Histology and Histochemistry of Rabbits Liver and Kidney

Prednisolone and prednisone are synthetic corticosteroids used to treat different diseases. They are well known to be used for treating many conditions like asthma, autoimmune diseases, many skin conditions, and may help to prevent or at least to suppress inflammations and immune responses. It was proved previously the correlation between prednisolone and the function of liver in patients having liver problems. In patients with alcoholic hepatitis, for example, prednisolone was accompanied with a short-term reduction in the rates of mortality, but this effect was not clear after 2 years. This research was performed to study the possible effects of prednisolone on the histology and the enzyme histochemistry of the liver and kidney in healthy rabbits. Twelve females adult rabbits (Six animals considered as treated group and other six animals as control group) were used in this experiment. After two weeks of adaptation time, treatment by the drug began. Animals treated by prednisolone oral dose 20 mg daily by gavage. Animals sacrificed under anesthesia, then ordinary histological sections (stained with hematoxylin-eosin) and frozen sections (by freezing microtome for Alp activity) of liver and kidney were prepared. The histological results and the ALP activity in both liver and kidney were found to be normal in treated group in compare with the control group. Prednisolone has many various effects on the physiology, psychology, immunology, even the molecular and genetics, varied from beneficial effects to undesired side effects. In the field of hepatology, prednisolone treatment was found to ameliorate many symptoms and enhance many biochemical and histologic abnormal changes in many types of liver diseases like autoimmune hepatitis, liver cirrhosis, septic shock patients, and cases of liver transplantation. In conclusion; according to the results of this research there no any effects of prednisolone on histology of liver and kidney and the ALP activity in these organs.

Divergent Effects of a Transient Corticosteroid Therapy on Virus-Specific Quiescent and Effector CD8+ T Cells.

We investigated the influence of a transient treatment of corticosteroid on CD8+ T cells during herpesvirus infection. Dexamethasone, a synthetic corticosteroid, induced apoptosis of naïve and memory CD8+ T cells but virus-specific effector cells were spared. CD8+ T cell susceptibility was directly correlated with the expression of nr3c1. Both α-(HSV1) and γ-(MHV68) herpesvirus infection expanded CD8+ T cells down regulated nr3c1 indicating corticosteroid-mediated effects were not limited to one pathogen or the specific clonotype. Dexamethasone compromised anti-viral immunity to subsequent infections, likely through reductions in the naïve cell pool. Dexamethasone augmented the function and inflammatory tissue homing potential of effector cells via upregulation of CXCR3. Accordingly, an antibody neutralization of CXCR3 diminished dexamethasone-induced migration of CD8+ T cells to tissues resulting in increased virus burden. Our study therefore suggests that even a transient corticosteroid therapy influences both ongoing CD8+ T cell responses as well as the size of the naïve and memory repertoire.

Antagonizing the Glucocorticoid Receptor Impairs Explant-Induced Reactivation in Mice Latently Infected with Herpes Simplex Virus 1.

Herpes simplex virus 1 (HSV-1) establishes lifelong latent infections in neurons. Reactivation from latency can lead to serious recurrent disease, including stromal keratitis, corneal scarring, blindness, and encephalitis. Although numerous studies link stress to an increase in the incidence of reactivation from latency and recurrent disease, the mechanism of action is not well understood. We hypothesized that stress, via corticosteroid-mediated activation of the glucocorticoid receptor (GR), stimulates viral gene expression and productive infection during reactivation from latency. Consequently, we tested whether GR activation by the synthetic corticosteroid dexamethasone influenced virus shedding during reactivation from latency using trigeminal ganglion (TG) explants from Swiss Webster mice latently infected with HSV-1, strain McKrae. TG explants from the latently infected mice shed significantly higher levels of virus when treated with dexamethasone. Conversely, virus shedding from TG explants was significantly impaired when they were incubated with medium containing a GR-specific antagonist (CORT-108297) or stripped fetal bovine serum, which lacks nuclear hormones and other growth factors. TG explants from latently infected, but not uninfected, TG contained significantly more GR-positive neurons following explant when treated with dexamethasone. Strikingly, VP16 protein expression was detected in TG neurons at 8 hours after explant whereas infected-cell protein 0 (ICP0) and ICP4 protein expression was not readily detected until 16 hours after explant. Expression of all three viral regulatory proteins was stimulated by dexamethasone. These studies indicated corticosteroid-mediated GR activation increased the number of TG neurons expressing viral regulatory proteins, which enhanced virus shedding during explant-induced reactivation from latency.IMPORTANCE Herpes simplex virus 1 (HSV-1) establishes lifelong latent infections in neurons within trigeminal ganglia (TG); periodically, reactivation from latency occurs, leading to virus transmission and recurrent disease. Chronic or acute stress increases the frequency of reactivation from latency; how this occurs is not well understood. Here, we demonstrate that the synthetic corticosteroid dexamethasone stimulated explant-induced reactivation from latency. Conversely, a glucocorticoid receptor (GR) antagonist significantly impaired reactivation from latency, indicating that GR activation stimulated explant-induced reactivation. The viral regulatory protein VP16 was readily detected in TG neurons prior to infected-cell protein 0 (ICP0) and ICP4 during explant-induced reactivation. Dexamethasone induced expression of all three viral regulatory proteins following TG explant. Whereas the immunosuppressive properties of corticosteroids would facilitate viral spread during reactivation from latency, these studies indicate GR activation increases the number of TG neurons that express viral regulatory proteins during early stages of explant-induced reactivation.

Modeling Corticosteroid Pharmacokinetics and Pharmacodynamics, Part I: Determination and Prediction of Dexamethasone and Methylprednisolone Tissue Binding in the Rat.

The plasma and tissue binding properties of two corticosteroids, dexamethasone (DEX) and methylprednisolone (MPL), were assessed in the rat in anticipation of developing physiologically based pharmacokinetic and pharmacokinetic/pharmacodynamic models. The tissue-to-plasma partition coefficients (K P) of DEX and MPL were measured in liver, muscle, and lung in vivo after steady-state infusion and bolus injection in rats. Since K P is often governed by reversible binding to macromolecules in blood and tissue, an attempt was made to assess K P values of DEX and MPL by in vitro binding studies using rat tissue homogenates and to compare these estimates to those obtained from in vivo kinetics after dosing. The K P values of both steroids were also calculated in rat tissues using mechanistic tissue composition-based equations. The plasma binding of DEX and MPL was linear with moderate binding (60.5% and 82.5%) in male and female rats. In vivo estimates of steroid uptake appeared linear across the tested concentrations and K P was highest in liver and lowest in muscle for both steroids. Assessment of hepatic binding of MPL in vitro was severely affected by drug loss at 37°C in male liver homogenates, whereas DEX was stable in both male and female liver homogenates. With the exception of MPL in liver, in vitro-derived K P estimates reasonably agreed with in vivo values. The mechanistic equations modestly underpredicted K P for both drugs. Tissue metabolism, saturable tissue binding, and active uptake are possible factors that can complicate assessments of in vivo tissue binding of steroids when using tissue homogenates. SIGNIFICANCE STATEMENT: Assuming the free hormone hypothesis, the ratio of the unbound drug fraction in plasma and in tissues defines the tissue-to-plasma partition coefficient (K P), an important parameter in physiologically based pharmacokinetic modeling that determines total drug concentrations within tissues and the steady-state volume of distribution. This study assessed the plasma and tissue binding properties of the synthetic corticosteroids, dexamethasone and methylprednisolone, in rats using ultrafiltration and tissue homogenate techniques. In vitro-in vivo and in silico-in vivo extrapolation of K P was assessed for both drugs in liver, muscle, and lung. Although the extrapolation was fairly successful across the tissues, in vitro homogenate studies severely underpredicted the K P of methylprednisolone in liver, partly attributable to the extensive hepatic metabolism.

Modeling Corticosteroid Pharmacokinetics and Pharmacodynamics, Part II: Sex Differences in Methylprednisolone Pharmacokinetics and Corticosterone Suppression.

Methylprednisolone (MPL), a corticosteroid of intermediate potency, remains an important immunomodulatory agent for autoimmune diseases. Although sex differences in corticosteroid pharmacokinetics/pharmacodynamics (PK/PD) have been documented in humans, comprehensive preclinical assessments of such differences have not been conducted. Limited in vitro evidence indicates possible sex differences in corticosteroid PK and PD. Therefore, it is hypothesized that comparative PK/PD assessments of MPL disposition and selected PD actions in both sexes will provide insights into factors controlling sex differences in steroid responses. This report focused on the plasma and tissue pharmacokinetics of MPL and its adrenal suppressive effects. Because time-dependent (estrous) regulation of sex hormones in females can influence drug responses, female rats were studied in the proestrus (high estradiol/progesterone) and estrus (low estradiol/progesterone) phases of the reproductive cycle. Cohorts of male and female rats were given a 50 mg/kg bolus dose of MPL intramuscularly. Plasma and liver concentrations of MPL as well as plasma corticosterone concentrations were assayed using high-performance liquid chromatography. An enhanced minimal physiologically-based PK/PD model was developed to characterize MPL kinetics and corticosterone dynamics. The clearance of MPL was ∼3-fold higher in males compared with females, regardless of estrous phase, likely attributable to sex-specific hepatic metabolism in males. Strong inhibitory effects on adrenal suppression were observed in all animals. These temporal steroid profiles in plasma and tissues will be used to drive receptor/gene-mediated PD effects of MPL in both sexes, as described in a companion article (Part III). SIGNIFICANCE STATEMENT: Sex is a relevant factor influencing the pharmacokinetics (PK) and pharmacodynamics (PD) of drugs. Few preclinical PK/PD studies, however, include sex as a variable. Sex differences in the PK and adrenal suppressive effects of the synthetic corticosteroid, methylprednisolone, were assessed in male and female rats as a function of the 4-day rodent reproductive cycle. Drug exposure was 3-fold higher in females, regardless of estrous stage, compared with males. An extended minimal physiologically-based PK/PD model utilizing in vitro and in vivo measurements was developed and applied. These studies provide a framework to account for sex-dependent variability in drug and endogenous agonist (corticosterone) exposures, serving as a prelude to more intricate assessments of sex-related variability in receptor/gene-mediated PD corticosteroid actions.

Bovine Herpesvirus 1 Counteracts Immune Responses and Immune-Surveillance to Enhance Pathogenesis and Virus Transmission.

Infection of cattle by bovine herpesvirus 1 (BoHV-1) can culminate in upper respiratory tract disorders, conjunctivitis, or genital disorders. Infection also consistently leads to transient immune-suppression. BoHV-1 is the number one infectious agent in cattle that is associated with abortions in cattle. BoHV-1, as other α-herpesvirinae subfamily members, establishes latency in sensory neurons. Stressful stimuli, mimicked by the synthetic corticosteroid dexamethasone, consistently induce reactivation from latency in latently infected calves and rabbits. Increased corticosteroid levels due to stress have a two-pronged effect on reactivation from latency by: (1) directly stimulating viral gene expression and replication, and (2) impairing antiviral immune responses, thus enhancing virus spread and transmission. BoHV-1 encodes several proteins, bICP0, bICP27, gG, UL49.5, and VP8, which interfere with key antiviral innate immune responses in the absence of other viral genes. Furthermore, the ability of BoHV-1 to infect lymphocytes and induce apoptosis, in particular CD4+ T cells, has negative impacts on immune responses during acute infection. BoHV-1 induced immune-suppression can initiate the poly-microbial disorder known as bovine respiratory disease complex, which costs the US cattle industry more than one billion dollars annually. Furthermore, interfering with antiviral responses may promote viral spread to ovaries and the developing fetus, thus enhancing reproductive issues associated with BoHV-1 infection of cows or pregnant cows. The focus of this review is to describe the known mechanisms, direct and indirect, by which BoHV-1 interferes with antiviral immune responses during the course of infection.

The Glucocorticoid Receptor (GR) Stimulates Herpes Simplex Virus 1 Productive Infection, in Part Because the Infected Cell Protein 0 (ICP0) Promoter Is Cooperatively Transactivated by the GR and Krüppel-Like Transcription Factor 15.

Following acute infection, herpes simplex virus 1 (HSV-1) establishes lifelong latency in neurons. Physical, emotional, and chemical stresses are linked to increasing the incidence of reactivation from latency, but the mechanism of action is not well understood. In general, stress increases corticosteroid levels, leading to activation of the glucocorticoid receptor (GR), a pioneer transcription factor. Consequently, we hypothesized that stress-mediated activation of the GR can stimulate productive infection and viral gene expression. New studies demonstrated that the GR-specific antagonist (CORT-108297) significantly reduced HSV-1 productive infection in mouse neuroblastoma cells (Neuro-2A). Additional studies demonstrated that the activated GR and Krüppel-like transcription factor 15 (KLF15) cooperatively transactivated the infected cell protein 0 (ICP0) promoter, a crucial viral regulatory protein. Interestingly, the synthetic corticosteroid dexamethasone and GR or KLF15 alone had little effect on ICP0 promoter activity in transfected Neuro-2A or Vero cells. Chromatin immunoprecipitation (ChIP) studies revealed that the GR and KLF15 occupied ICP0 promoter sequences important for transactivation at 2 and 4 h after infection; however, binding was not readily detected at 6 h after infection. Similar results were obtained for cells transfected with the full-length ICP0 promoter. ICP0 promoter sequences lack a consensus "whole" GR response element (GRE) but contain putative half-GREs that were important for dexamethasone induced promoter activity. The activated GR stimulates expression of, and interacts with, KLF15; consequently, these data suggest KLF15 and the GR form a feed-forward loop that activates viral gene expression and productive infection following stressful stimuli.IMPORTANCE The ability of herpes simplex virus 1 (HSV-1) to periodically reactivate from latency results in virus transmission and recurrent disease. The incidence of reactivation from latency is increased by chronic or acute stress. Stress increases the levels of corticosteroids, which bind and activate the glucocorticoid receptor (GR). Since GR activation is an immediate early response to stress, we tested whether the GR influences productive infection and the promoter that drives infected cell protein 0 (ICP0) expression. Pretreatment of cells with a GR-specific antagonist (CORT-108297) significantly reduced virus replication. Although the GR had little effect on ICP0 promoter activity alone, the Krüppel-like transcription factor 15 (KLF15) cooperated with the GR to stimulate promoter activity in transfected cells. In transfected or infected cells, the GR and KLF15 occupied ICP0 sequences important for transactivation. Collectively, these studies provide insight into how stress can directly stimulate productive infection and viral gene expression.

Trace analysis of corticosteroids (CSs) in environmental waters by liquid chromatography–tandem mass spectrometry

Natural and synthetic corticosteroids (CSs) are a class of steroid hormones which could potentially disturb the corticosteroid signaling pathways in wildlife and humans. In this study, a sensitive and robust analytical method using solid phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) was developed for simultaneous analysis of sub-ng/L concentrations of 26 CSs in highly complex natural water matrices. The method performance was validated for WWTP influent, effluent, surface water and finished drinking water. Low practical quantification levels (PQLs) were achieved as 0.008–0.16 ng/L in finished drinking water, 0.019–0.50 ng/L in surface water, 0.047–1.5 ng/L in WWTP effluent, and 0.10–3.1 ng/L in WWTP influent, respectively, with the recoveries ranging from 70% to 130%. The cleanup performance and matrix interferences were also evaluated. This method was then applied to the analysis of target CSs in WWTP influent and effluent samples collected from a local WWTP, as well as surface water downstream of the WWTP outfall, detecting an average summed CS concentration of 744 ng/L in influent, 23.4 ng/L in effluent and 10.9 ng/L in surface water. Four synthetic CSs (triamcinolone acetonide, fluocinolone acetonide, clobetasol propionate, and fluticasone propionate) were found poorly removed in the WWTP. The developed method provides a tool to obtain occurrence data of corticosteroids in environmental waters, which will permit assessing their risk to environmental organisms.

Histological Study of The Effect of Administration of Exogenous Glucocorticoids on the Testis of Albino Rats

Glucocorticoids are prescribed by many physicians to treat inflammatory conditions that affect the different body organs as lungs, skin, joints, digestive tract and eyes. Common diseases that frequently require treatment with glucocorticoids include bronchial asthma, inflammatory bowel syndrome and some types of arthritis. Cortisol is the principal circulating glucocorticoids in human and is secreted under the control of the hypothalmo-pituitary-adrenal axis. Dexamethazone is a synthetic pregnane corticosteroid and derivative of cortisol (hydrocortisone). It was first made in 1957 and is used in the treatment of many conditions, including rheumatic problems, a number of skin diseases, severe allergies, bronchial asthma, chronic obstructive lung disease, croup in children, brain and spinal cord surgery. Also cortisol has frequently been indicated as a major factor mediating the suppressive effect of stress on reproductive system problems because the stress interferes with the function of the brain-pituitary-gonad (BPG) axis so prolonged elevated cortisol levels, implicated in stress adaptation, inhibit pubertal development in the male gonads. The aim of the work is to study the histological changes that may occur in the albino rat testis after administration of dexamethasone and to investigate the possibility of recovery of testis after drug stoppage. Thirty prepubertal male albino rats were used in this study and divided into three equal groups. Group I (control), group II (dexamethasone-treated for 2 weeks) and Group III (recovery group) it manage as group II, then left untreated for further 2 weeks for studying the possibility of testicular recovery. At the time of animal sacrifice, the testes of all groups were dissected out, processed and stained with H&E. and toluidine blue stains then examined by light microscope. Histological examination of the sections of the testes of the dexamethasone treated group showed that the seminiferous tubules attained different shapes and had lost the normal distribution of their epithelial lining with the appearance of several layers of dark type spermatogonia that were ensheathed by the irregular basement membrane. The lumina of the affected tubules contained exfoliated germ cells. Also some germ cells showed apoptosis with small peripheral nuclei. Leydig cells appeared with peripherally located nuclei. Histological examination of the sections of the testes of the dexamethasone recovery group had manifested still distorted seminiferous tubules with no absolute return to its normal histological structure. So in clinical practice, therapeutic doses and periods of administration of dexamethasone must be carefully adjusted especially in younger ages.

Dexamethasone Facilitates NF-κB Signal Pathway in TNF-α Stimulated Rotator Cuff Tenocytes.

Corticosteroids are commonly used for pain control in rotator cuff tear. Deregulated NF-κB activation is a hallmark of chronic inflammatory diseases and has been responsible for the pathogenesis of rotator cuff tear. The Dexamethasone(DEXA) is a synthetic corticosteroid. The purpose of this study was to examine the exact effect of dexamethasone on NF-κB signaling in rotator cuff tear. We measured NF-κB expression in four groups: control, TNF-α-treated, DEXA-treated, and combined treatment with TNF-α and DEXA. Tenocytes were isolated from patients with rotator cuff tears and pre-incubated with TNF-α (10 ng/ml), DEXA (1 µM), or both of them for 10 min, 1 h, and 2 h. Expression of p65, p50, and p52 in the nuclei and cytosol was analyzed by western blotting and immunofluorescence imaging using confocal microscopy. We also evaluated nucleus/cytosol (N/C) ratios of p65, p50, and p52. In our study, the combined treatment with DEXA and TNF-α showed increased N/C ratios of p65, p50, and p52 compared with those in the TNF-α group at all time points. Additionally, in the DEXA group, N/C ratios of p65, p50, and p52 gradually increased from 10 min to 2 h. In conclusion, DEXA promoted the nuclear localization of p65, p50, and p52, but was not effective in inhibiting the inflammatory response of TNF-α-stimulated rotator cuff tear.

Analysis of corticosteroids in samples of animal origin using QuEChERS and ultrahigh-performance liquid chromatography coupled to high-resolution mass spectrometry.

A rapid and sensitive method for the confirmatory analysis of eight synthetic corticosteroids (betamethasone, dexamethasone, prednisolone, 6-methylprednisolone, triamcinolone, flumethasone, beclomethasone, fluocinolone acetonide) is proposed. The method is useful for detecting illegal treatments in different animal species. It consists of an extraction and cleanup using the quick, easy, cheap, effective, rugged, and safe (QuEChERS) strategy. Quantitative determination is achieved by ultrahigh-performance liquid chromatography coupled to high-resolution mass spectrometry with heated electrospray ionization in negative mode. Quantification is performed using surrogate matrix-matched standard calibration curve with dexamethasone-D4 as the internal standard. The method was validated for analyzing liver samples according to the criteria established by Decision 2002/657/EC. Linearity was assessed in the 1-10μgkg-1 range and linear correlation coefficients were over 0.99 for all the analytes. CCα ranged from 0.04 to 0.16μgkg-1 for substances without maximum residue limit. The method allows confident quantification and confirmation of corticosteroids in liver samples, and its simplicity makes it suitable for analyzing large numbers of samples.

Interaction of prednisone with dsDNA at silver nanoparticles/poly(glyoxal-bis(2-hydroxyanil))/dsDNA modified electrode and its analytical application

This paper reports the fabrication of an electrochemical DNA biosensor for the electrochemical determination of prednisone (PRD), which is a synthetic corticosteroid. For this purpose, silver nanoparticles (AgNPs) and a new polymer film poly(glyoxal-bis(2-hydroxyanil)) (P(GBHA)) were electrochemically deposited on a glassy carbon electrode (GCE), respectively. Then, an electrochemical DNA biosensor was prepared onto this electrode surface (GCE/AgNPs/P(GBHA)) by the immobilization of dsDNA using a chronoamperometry method. The proposed electrode was characterized by FESEM, XPS, and cyclic voltammetry (CV). The interaction between the PRD and dsDNA immobilized on the GCE/AgNPs/P(GBHA) electrode was investigated via a differential pulse voltammetry (DPV) method and UV–Vis spectrophotometry. The experimental factors affecting the interaction between the PRD concentration and dsDNA were optimized. The fabricated biosensor showed a wide linear response in a PRD concentration range of 1.0–50.0 μg mL−1 depending on both the adenine and guanine base signals. The detection limit based on the guanine and adenine signals was 0.3 μg mL−1 and 0.25 μg mL−1, respectively. The sensor exhibited excellent anti-interferential ability, good stability and reproducibility and was satisfactorily employed for the electrochemical assay of PRD in serum samples. The new DNA biosensor can be utilized for the sensitive, accurate and rapid analysis of PRD.

The bovine herpesvirus 1 regulatory proteins, bICP4 and bICP22, are expressed during the escape from latency.

Following acute infection of mucosal surfaces by bovine herpesvirus 1 (BoHV-1), sensory neurons are a primary site for lifelong latency. Stress, as mimicked by the synthetic corticosteroid dexamethasone, consistently induces reactivation from latency. Two viral regulatory proteins (VP16 and bICP0) are expressed within 1h after calves latently infected with BoHV-1 are treated with dexamethasone. Since the immediate early transcription unit 1 (IEtu1) promoter regulates both BoHV-1 infected cell protein 0 (bICP0) and bICP4 expressions, we hypothesized that the bICP4 protein is also expressed during early stages of reactivation from latency. In this study, we tested whether bICP4 and bICP22, the only other BoHV-1 protein known to be encoded by an immediate early gene, were expressed during reactivation from latency by generating peptide-specific antiserum to each protein. bICP4 and bICP22 protein expression were detected in trigeminal ganglionic (TG) neurons during early phases of dexamethasone-induced reactivation from latency, operationally defined as the escape from latency. Conversely, bICP4 and bICP22 were not readily detected in TG neurons of latently infected calves. In summary, it seems clear that all proteins encoded by known BoHV-1 IE genes (bICP4, bICP22, and bICP0) were expressed during early stages of dexamethasone-induced reactivation from latency.

Development and characterization of methylprednisolone loaded delayed release nanofibers

Nanofibers have gained significant attention recently due to its wide applications in pharmaceutical area. Methylprednisolone (MP), a synthetic corticosteroid drug, has been used to treat a number of diseases. However, MP can lead to ulceration by acting as a direct irritant to the gastric mucosa. This study aimed to design MP loaded electrospun nanofibers for delayed release drug delivery system. The MP loaded nanofibers were prepared with enteric polymers such as Eudragit L100-55, Eudragit S100 and Kollicoat MAE100-55. Viscosity, conductivity and surface tension of the solutions were analyzed before electrospinning. DSC studies of polymers and MP were also conducted. After fabrication, the nanofibers were evaluated in terms of surface morphology and drug release. The drug release kinetics were calculated to predict the release mechanism. The fiber diameter increased with increasing drug concentration. The increase in mean nanofiber diameter caused the delayed release of MP. The nanofibers prepared with Eudragit S100 polymer with 10:0.5 polymer:drug ratio showed the optimum delayed release profile. The release profiles were best fitted to Weibull model, which shows complex release mechanism. Uniaxial electrospinning could be considered as a simple, inexpensive and effective method for producing delayed release drug delivery system.