Dexamethasone Inhibition Research Articles

FGF‐Mimicking Triphen[3]arene Peptide Self‐Assembly to Accelerate Muscle Regeneration and Repair

AbstractBioactive peptides play crucial roles in the biomedicine fields including cancer therapy and regenerative medicine due to their favorable biocompatibility, low immunogenicity, and excellent biological activity. However, their low stability greatly limits their clinical application. Herein, a novel bioactive peptide delivery strategy is reported that utilizes triphen[3]arene polyvalent‐conjugated bioactive peptides to induce self‐assembly and form nanofibers to enhance the in vivo stability and bioactivity of bioactive peptides. Specifically, a water‐soluble triphen[3]arene (WTP3(YRSRK)6, Comp. 2) containing six FGF‐mimicking peptides, primarily comprising two components: triphen[3]arene serves as a skeleton molecule and an assembly motif with multiple customizable sites, while YRSRK is a pentapeptide with fibroblast growth factor 2 (FGF‐2) biological activity. Despite the presence of the inhibitor dexamethasone (Dex), Comp. 2 continued to enhance cell proliferation by 15% and rescued 17% of cells from apoptosis. The administration of Comp. 2 resulted in improved restoration of skeletal muscle atrophy and functional damage in mice. The mean grip strength increased by 42%, and the calf muscle volume increased by 17%. This innovative approach of utilizing macrocycle polyvalent conjugated bioactive peptides offers a universal method for enabling bioactive peptides to produce sustained and efficient biological effects, potentially advancing the development of promising peptide‐based nanomedicines.

SOST/Sclerostin impairs the osteogenesis and angiogesis in glucocorticoid-associated osteonecrosis of femoral head.

Glucocorticoid-associated osteonecrosis of the femoral head (GA-ONFH) is a progressive bone disorder which frequently results in femoral head collapse and hip joint dysfunction. Sclerostin (SOST) is principally secreted by osteocytes in bone and plays an important role in bone homeostasis and homeostasis of skeletal integrity. Our previous study reported that short-term use of glucocorticoid increased serum sclerostin levels. Here this study is aimed to identify whether sclerostin played an essential role in the occurrence and development of GA-ONFH. Glucocorticoid-induced osteonecrosis of femoral head (ARCO stage II) samples were collected and sclerostin staining was conducted. Osteocyte cell line Ocy454, MC3T3-E1 and endothelial cells was used. MC3T3-E1 or endothelial cells were co-cultured with Ocy454 or SOST-silencing Ocy454 in presence of dexamethasone to mimic the crosstalk of various cells in the bone niche. GA-ONFH rat model and SOST knockout model was built to better understand the phenomenon in vivo. Sclerostin was highly concentrated in osteonecrosis patient sample in the necrotic area. Co-culture with osteocytes aggravated the inhibition of dexamethasone on MC3T3-E1 and endothelial cells. Sclerostin derived from osteocytes impaired osteogenesis and angiogenesis via inhibiting the Wnt pathway. In GA-ONFH rat model, SOST knockout ameliorated the incidence of osteonecrosis and improved bone metabolism compared with the wild type group through histological, immunohistochemical and bone metabolic analyses. Sclerostin contribute to pathologic process of GA-ONFH by impairing osteogenesis and angiogenesis.

Bioactive peptide relieves glucocorticoid-induced osteoporosis by giant macrocyclic encapsulation

Bioactive peptides play a crucial role in the field of regenerative medicine and tissue engineering. However, their application in vivo and clinic is hindered by their poor stability, short half-life, and low retention rate. Herein, we propose a novel strategy for encapsulating bioactive peptides using giant macrocycles. Platelet-derived growth factor (PDGF) bioactive mimicking peptide Nap-FFGVRKKP (P) was selected as the representative of a bioactive peptide. Quaterphen[4]arene (4) exhibited extensive host-guest complexation with P, and the binding constant was (1.16 ± 0.10) × 107 M−1. In vitro cell experiments confirmed that P + 4 could promote the proliferation of BMSCs by 2.27 times. Even with the addition of the inhibitor dexamethasone (Dex), P + 4 was still able to save 76.94% of the cells in the control group. Compared to the Dex group, the bone mass of the mice with osteoporosis in the P + 4 group was significantly increased. The mean trabecular thickness (Tb.Th) increased by 17.03%, and the trabecular bone volume fraction (BV/TV) values increased by 40.55%. This supramolecular bioactive peptide delivery strategy provides a general approach for delivering bioactive peptides and opens up new opportunities for the development of peptide-based drugs.

Weight loss and vitamin D improve hyporesponsiveness to corticosteroids in obese asthma.

Obesity negatively impacts on asthma response to inhaled corticosteroids by unknown mechanisms. Objective: To demonstrate that the poor response to inhaled corticosteroids in obese asthma is associated with an impaired anti-inflammatory activity of corticosteroids and vitamin D deficiency, both improved by weight loss. 23 obese asthmatics (OA) [18 females; median age (interquartile range) 56 (51-59) years], 14 non-obese asthmatics (NOA) [11 females; 53 (43-60) years], 15 obese (O) [13 females; 47 (45-60) years], and 19 healthy controls (HC) [14 females; 43 (34-56) years] were enrolled. 10 OA and 11 O patients were evaluated at baseline (V1) and six months after (V2) bariatric surgery. Corticosteroid response was measured by dexamethasone inhibition of peripheral blood mononuclear cell (PBMC) proliferation. Lung function, serum levels of leptin, adiponectin, and vitamin D were measured at V1 and V2. We found a reduced response to dexamethasone in PBMCs of O and OA patients with respect to NOA and HC subjects, that inversely correlated with the diponectin/leptin ratio and vitamin D levels. Bariatric surgery improved corticosteroid responses in O and OA patients and normalized adiponectin/leptin ratio and vitamin D levels. Exposure of PBMCs to vitamin D potentiated the antiproliferative effects of corticosteroids. Dexamethasone and vitamin D induced similar MKP-1 expression in O and OA patients. We found a reduced response to dexamethasone in PBMCs of O and OA patients with respect to NOA and HC subjects, that inversely correlated with the adiponectin/leptin ratio and vitamin D levels. Bariatric surgery improved corticosteroid responses in O and OA patients and normalized adiponectin/leptin ratio and vitamin D levels. Exposure of PBMCs to vitamin D potentiated the antiproliferative effects of corticosteroids. Dexamethasone and vitamin D induced similar MKP-1 expression in O and OA patients.

Anti-inflammatory effects of dexamethasone in COVID-19 patients: Translational population PK/PD modeling and simulation.

Dexamethasone (DEX) given at a dose of 6 mg once-daily for 10 days is a recommended dosing regimen in patients with coronavirus disease 2019 (COVID-19) requiring oxygen therapy. We developed a population pharmacokinetic and pharmacodynamic (PopPK/PD) model of DEX anti-inflammatory effects in COVID-19 and provide simulations comparing the expected efficacy of four dosing regimens of DEX. Nonlinear mixed-effects modeling and simulations were performed using Monolix Suite version 2021R1 (Lixoft, France). Published data for DEX PK in patients with COVID-19 exhibited moderate variability with a clearance of about half that in healthy adults. No accumulation of the drug was expected even with daily oral doses of 12 mg. Indirect effect models of DEX inhibition of TNFα, IL-6, and CRP plasma concentrations were enacted and simulations performed for DEX given at 1.5, 3, 6, and 12 mg daily for 10 days. The numbers of individuals that achieved specified reductions in inflammatory biomarkers were compared among the treatment groups. The simulations indicate the need for 6 or 12 mg daily doses of DEX for 10 days for simultaneous reductions in TNFα, IL-6, and CRP. Possibly beneficial is DEX given at a dose of 12 mg compared to 6 mg. The PopPK/PD model may be useful in the assessment of other anti-inflammatory compounds as well as drug combinations in the treatment of cytokine storms.

Dissecting the mechanisms underlying the Cytokine Release Syndrome (CRS) mediated by T Cell Bispecific Antibodies.

Target-dependent TCB activity can result in strong and systemic release of cytokines that may develop into Cytokine Release Syndrome (CRS), highlighting the need to understand and prevent this complex clinical syndrome. We explored the cellular and molecular players involved in TCB-mediated cytokine release by single cell RNA sequencing of whole blood treated with CD20-TCB together with bulk RNA sequencing of endothelial cells exposed to TCB-induced cytokine release. We used the in vitro whole blood assay and an in vivo DLBCL model in immunocompetent humanized mice to assess the effects of dexamethasone, anti-TNF-a, anti-IL-6R, anti-IL-1R and inflammasome inhibition, on TCB-mediated cytokine release and anti-tumor activity. Activated T cells release TNF-α, IFN-γ, IL-2, IL-8 and MIP-1β, which rapidly activate monocytes, neutrophils, DCs and NKs along with surrounding T cells to amplify the cascade further, leading to TNF-α, IL-8, IL-6, IL-1β, MCP-1, MIP-1α, MIP-1β and IP-10 release. Endothelial cells contribute to IL-6 and IL-1β release and at the same time release several chemokines (MCP-1, IP-10, MIP-1α and MIP-1β). Dexamethasone and TNF-α blockade efficiently reduced CD20-TCB-mediated cytokine release while IL-6R blockade, inflammasome inhibition and IL1-R blockade induced a less pronounced effect. Dexamethasone, IL-6R blockade, IL-1R blockade and the inflammasome inhibitor did not interfere with CD20-TCB activity, in contrast to TNF-α blockade, which partially inhibited anti-tumor activity. Our work sheds a new light on the cellular and molecular players involved in cytokine release driven by TCBs and provides rationale for the prevention of CRS in patients treated with TCBs.

Exploration of clinical pathway-oriented optimal management diagnosis and treatment model for rare diseases

This study takes Cushing's syndrome, a rare disease, as a model, and adopts the path of "Plan, Do, Check, Action" (PDCA) to explore new methods to optimize the clinical path, can improve the quality and efficiency of diagnosis and treatment of rare diseases. After sorting out the problems existing in the previous diagnosis and treatment mode, our team optimizes the path in various ways and establishes a standard operation procedure (SOP) for the new path. In the evaluation of the optimized mode, 55 patients with Cushing's syndrome were admitted to the Department of Endocrinology, Peking Union Medical College Hospital, including 19 males and 36 females, aged (41.8±14.4) years (6-68 years). The pathway group (28 cases) and the control group (27 cases) were divided according to whether they were included in the new path management at the time of admission, and the effect of path optimization was assessed in terms of time, efficacy, safety and cost. The results showed that compared with the control group, the pathway group had a shorter time of hospitalization in the Department of Endocrinology and critical tests, such as blood cortisol rhythm, low-dose dexamethasone inhibition test, and bilateral inferior petrosal sinus sampling (all P<0.05). There was no significant differences in the decrease of total cortisol after operation, the incidence of postoperative complications, and hospitalization expenses (all P>0.05). The optimized path improves the medical efficiency while ensuring medical quality, safety and no increase in cost. This study proposes PDCA path optimization for complex diseases and establishes SOP process, which provides experience in management optimization for the patient-centered and clinical path-oriented diagnosis and treatment mode of rare diseases.

Sex-Dimorphic Glucocorticoid Receptor Regulation of Hypothalamic Primary Astrocyte Glycogen Metabolism: Interaction with Norepinephrine.

Astrocyte glycogen is a critical metabolic variable that impacts hypothalamic control of glucostasis. Glucocorticoid hormones regulate peripheral glycogen, but their effects on hypothalamic glycogen are not known. A hypothalamic astrocyte primary culture model was used to investigate the premise that glucocorticoids impose sex-dimorphic independent and interactive control of glycogen metabolic enzyme protein expression and glycogen accumulation. The glucocorticoid receptor (GR) agonist dexamethasone (DEX) down-regulated glycogen synthase (GS), glycogen phosphorylase (GP)-brain type (GPbb), and GP-muscle type (GPmm) proteins in glucose-supplied male astrocytes, but enhanced these profiles in female. The catecholamine neurotransmitter norepinephrine (NE) did not alter these proteins, but amplified DEX inhibition of GS and GPbb in male or abolished GR stimulation of GPmm in female. In both sexes, DEX and NE individually increased glycogen content, but DEX attenuated the magnitude of noradrenergic stimulation. Glucoprivation suppressed GS, GPbb, and GPmm in male, but not female astrocytes, and elevated or diminished glycogen in these sexes, respectively. Glucose-deprived astrocytes exhibit GR-dependent induced glycogen accumulation in both sexes, and corresponding loss (male) or attenuation (female) of noradrenergic-dependent glycogen build-up. Current evidence for GR augmentation of hypothalamic astrocyte glycogen content in each sex, yet divergent effects on glycogen enzyme proteins infers that glucocorticoids may elicit opposite adjustments in glycogen turnover in each sex. Results document GR modulation of NE stimulation of glycogen accumulation in the presence (male and female) or absence (female) of glucose. Outcomes provide novel proof that astrocyte energy status influences the magnitude of GR and NE signal effects on glycogen mass.

Repurposing of Drugs and HTS to Combat SARS-CoV-2 Main Protease Utilizing Structure-Based Molecular Docking

Background: COVID-19, first reported in China, from the new strain of severe acute respiratory syndrome coronaviruses (SARS-CoV-2), poses a great threat to the world by claiming uncountable lives. SARS-CoV-2 is a highly infectious virus that has been spreading rapidly throughout the world. In the absence of any specific medicine to cure COVID-19, there is an urgent need to develop novel therapeutics, including drug repositioning along with diagnostics and vaccines to combat the COVID-19. Many antivirals, antimalarials, antiparasitic, antibacterials, immunosuppressive anti-inflammatory, and immunoregulatory agents are being clinically investigated for the treatment of COVID-19. Objectives: The earlier developed one parameter regression model correlating the dock scores with in vitro anti-SARS-CoV-2 main protease activity well predicted the six drugs viz remdesivir, chloroquine, favipiravir, ribavirin, penciclovir, and nitazoxanide as potential anti-COVID agents. To further validate our earlier model, the biological activity of nine more recently published SARS-CoV-2 main protease inhibitors has been predicted using our previously reported model. Methods: In the present study, this regression model has been used to screen the existing antiviral, antiparasitic, antitubercular, and anti pneumonia chemotherapeutics utilizing dock score analyses to explore the potential including mechanism of action of these compounds in combating SARS-CoV-2 main protease. Results: The high correlation (R=0.91) explaining 82.3% variance between the experimental versus predicted activities for the nine compounds is observed. It proves the robustness of our developed model. Therefore, this robust model has been further improved, taking a total number of 15 compounds to formulate another model with an R-value of 0.887 and the explained variance of 78.6%. These models have been used for high throughput screening (HTS) of the 21 diverse compounds belonging to antiviral, antiparasitic, antitubercular, and anti pneumonia chemotherapeutics as potential repurpose agents to combat SARS-CoV-2 main protease. The models screened that the drugs bedaquiline and lefamulin have higher binding affinities (dock scores of -8.989 and -9.153 Kcal/mol respectively) than the reference compound N-[2-(5-fluoranyl-1~H-indol-3-yl)ethyl]ethanamide (dock score of -7.998 Kcal/Mol), as well as higher predicted activities with pEC50 of 0.783 and 0.937 μM and the 0.611 and 0.724 μM respectively. The clinically used repurposed drugs dexamethasone and cefixime have been predicted with pEC50 values of -0.463 and -0.622 μM and -0.311 and -0.428 μM respectively for optimal inhibition. The drugs such as doxycycline, cefpodoxime, ciprofloxacin, sparfloxacin, moxifloxacin, and TBAJ-876 showed moderate binding affinity corresponding to the moderate predicted activity (-1.540 to -1.109 μM). Conclusion: In the present study, validation of our previously developed dock score-based one parametric regression model has been carried out by predicting 9 more SARS-CoV-2 main protease inhibitors. Another model has been formulated to explore the model's robustness. These models have been taken as a barometer for the screening of more potent compounds. The HTS revealed that the drugs such as bedaquiline and lefamulin are highly predicted active compounds, whereas dexamethasone and cefixime have optimal inhibition towards SARS-CoV-2 main protease. The drugs such as doxycycline, cefpodoxime, ciprofloxacin, sparfloxacin, moxifloxacin, and TBAJ-876 have moderately active compounds towards the target inhibition.

Design and optimization of ROS-reactive nanocarriers for controlled release of dexamethasone and real-time inhibition of mast cell activation

Upon activation, mast cells release many mediators, including reactive oxygen species (ROS) and tumor necrosis factor (TNF) orchestrating allergic inflammation. Nanocarriers (NCs) that can detect mast cell activation and respond by releasing anti-inflammatory compounds in real-time, would and effective therapy.

Effects of glucocorticoids on the proliferation of CD19 CAR-T cells targeting B-cell tumor cell lines

目的评估糖皮质激素对CD19嵌合抗原受体T细胞（CAR-T细胞）靶向杀瘤过程中增殖的影响。方法健康志愿者的外周血单个核细胞（PBMC）作为T细胞来源，经CD3磁珠分选及CD19 CAR慢病毒转染制备CD19 CAR-T细胞；采用流式细胞术（FCM）测定CD19 CAR-T细胞转染率及其在培养体系中所占比例；采用CFDA SE细胞增殖示踪荧光探针试剂标记CD19 CAR-T细胞后测定其荧光强度；LDH细胞毒性检测方法检测不同浓度的糖皮质激素对B细胞肿瘤细胞株杀伤活性的影响。结果①CD19 CAR-T细胞CD19 CAR转染率为（51.34±5.28）％。②24 h后不同剂量甲泼尼龙对Nalm6、Pfeiffer及U2932细胞的杀伤活性高于地塞米松，48 h后低浓度（4 mg/ml）甲泼尼龙对Nalm6、Pfeiffer、U2932细胞杀伤活性高于低浓度（0.75 mg/ml）地塞米松，而高浓度（12 mg/ml）甲泼尼龙杀伤活性低于高浓度（2.25 mg/ml）地塞米松。但各个时间不同剂量甲泼尼龙组对EHEB细胞的杀伤活性均低于对应时间、剂量的地塞米松。③CD19 CAR-T细胞在不同浓度糖皮质激素作用下的比例及平均荧光强度比较，地塞米松对CD-19 CAR-T细胞的增殖抑制作用强于甲泼尼龙，两种糖皮质激素的高浓度组较低浓度组对CD19 CAR-T细胞的增殖抑制作用更明显。④CD19 CAR-T细胞与不同肿瘤细胞共培养体系中，其比例及平均荧光强度比较，地塞米松对CD19 CAR-T细胞的增殖抑制作用强于甲泼尼龙，两种糖皮质激素的高浓度组较低浓度组对CD19 CAR-T细胞的增殖抑制更明显。结论CD19 CAR-T细胞靶向不同肿瘤细胞株过程中地塞米松对CD19 CAR-T细胞的扩增和增殖抑制作用大于甲泼尼龙，高剂量组该抑制作用更加明显。

Treatment and protective effects of metalloproteinase inhibitors alone and in combination with N-Acetyl cysteine plus vitamin E in rats exposed to aflatoxin B1

This study was conducted to investigate the effects of matrix metalloproteinase (MMP) inhibitors dexamethasone and minocycline administrations —both single and in combination with N-acetylcysteine (NAC) and vitamin E—on the tissue distribution and lethal dose (LD)50 of aflatoxin (AF)B1 in rats. We performed this study on male Wistar rats (8–10 weeks) in two phases. In the first phase, rats were administered dexamethasone (5 and 20 mg/kg) and minocycline (45 and 90 mg/kg), both as single treatments and in combination with NAC (200 mg/kg) and vitamin E (600 mg/kg); these treatments followed AFB1 administration (2 mg/kg). In the second phase, the therapeutic effect value (TEV) was calculated to determine the treatment effect on the LD50 level of AFB1. The tissue affinity of AFB1 from high to low was liver, kidney, intestine, brain, heart, spleen, lung, testis, and vitreous humor, respectively. Dexamethasone at the 20 mg/kg dose significantly reduced AFB1 concentrations in the plasma and the other tissues, except for the vitreous humor. The effects of minocycline on the plasma and tissue concentrations of AFB1 varied by dose and tissue. The combinations of dexamethasone or minocycline with NAC and vitamin E increased the AFB1 concentrations in the plasma and all tissues, except for vitreous humor and liver. In male rats, the LD50 value of AFB1 was 11.86 mg/kg. The TEV of dexamethasone (20 mg/kg) was calculated to be 1.5. Dexamethasone can be administered in repeated doses at ≥20 mg/kg to increase survival in AFB1 poisoning.

Dexamethasone and p38 MAPK inhibition of cytokine production from human lung fibroblasts.

Lung fibroblasts are involved in airway inflammation and remodelling in COPD. We report an investigation of the effects of combining a p38 MAPK inhibitor with a corticosteroid on cytokine production by a human lung fibroblast cell line and primary fibroblasts obtained from human lung tissue. Our main interest was to determine whether additive or synergistic anti‐inflammatory effects would be observed. We observed inhibition of IL‐6 and CXCL8 secretion from both lung fibroblast models by dexamethasone (maximal inhibition 40–90%) and the p38 MAPK inhibitor BIRB (maximal inhibition 30–60%), used alone and evidence of increased anti‐inflammatory effects when used in combination. This combination effect was more apparent for TNF‐a stimulated cytokine production (maximal inhibition increased by 10–20%). Interaction ratio analysis showed this enhanced effect to be additive rather than synergistic interaction. Similar results were obtained using both fibroblast cell culture models. Combining a p38 MAPK to corticosteroids may help reduce fibroblast mediated inflammation in COPD.

Modifying gap junction communication in cancer therapy

AimDrug delivery is crucial for therapeutic efficacy and gap junction communication channels (GJIC) facilitate movement within the tumour. Pro-drug activation, a modality of cancer therapy leads to Ganciclovir triphosphate (GCV-TP) incorporation into newly synthesized DNA resulting in cell death. The objective was to enhance, with Histone deacetylase inhibitors (HDACi) and All Trans Retinoic Acid (ATRA), GJIC, crucial for drug delivery, and with combination, abrogate the observed detrimental effect of Dexamethasone (DXM). MethodsCell lines (NT8E, and HeLa) were pre-treated with Valproic Acid (VPA) (1 mM), 4 Phenyl Butyrate (4PB) (2 mM), ATRA (10 μM) and Dexamethasone (1 μM). Protein quantitated with the Bicinchoninic (BCA) assay for cell lysates, membrane and soluble fractions was assessed with Western blotting for Connexins (43, 26 and 32) and E-Cadherin. A qRT-PCR was done for CX 43-GJA1, CX 26-GJB2, CX 32-GJB1 and E-Cadherin, and normalized with Glyceraldehyde Phosphate dehydrogenase (GAPDH). Further, localization of Connexins (CX) and E-Cadherin, GJIC competence, pre-clinical in-vitro studies and the mechanism of cell death were evaluated. ResultsThere was no toxicity or change in growth patterns observed with the drugs. In both the cell lines CX 43 localized to the membrane whereas CX 32 and CX 26 were present but not membrane bound. E-Cadherin was present on the membrane in NT8E and completely absent in HeLa cells. Effects of HDACi, DXM and ATRA were seen on the expression of Connexins and E-Cadherin in both the cell lines. NT8E and HeLa cell lines showed enhanced GJIC with 4PB [30 %], VPA [36 %] and ATRA [54 %] with a 60 % increase in cytotoxicity and an abrogation of Dexamethasone inhibition on combination with VPA or ATRA. ConclusionAn enhancement of GJIC function by HDACi and ATRA increased cytotoxicity and could be effective in the presence of Dexamethasone, when combined with ATRA or VPA.

Critical Involvement of Calcium-Dependent Cytosolic Phospholipase A2α in Aortic Valve Interstitial Cell Calcification

The involvement of calcium-dependent cytosolic phospholipase A2α (cPLA2α) in aortic valve calcification is not exhaustively elucidated. Here, cPLA2α expression in aortic valve interstitial cell (AVIC) pro-calcific cultures simulating either metastatic or dystrophic calcification was estimated by qPCR, Western blotting, and counting of cPLA2α-immunoreactive cells, with parallel ultrastructural examination of AVIC calcific degeneration. These evaluations also involved pro-calcific AVIC cultures treated with cPLA2α inhibitor dexamethasone. cPLA2α over-expression resulted for both types of pro-calcific AVIC cultures. Compared to controls, enzyme content was found to increase by up to 300% and 186% in metastatic and dystrophic calcification-like cultures, respectively. Increases in mRNA amounts were also observed, although they were not as striking as those in enzyme content. Moreover, cPLA2α increases were time-dependent and strictly associated with mineralization progression. Conversely, drastically lower levels of enzyme content resulted for the pro-calcific AVIC cultures supplemented with dexamethasone. In particular, cPLA2α amounts were found to decrease by almost 88% and 48% in metastatic and dystrophic calcification-like cultures, respectively, with mRNA amounts showing a similar trend. Interestingly, these drastic decreases in cPLA2α amounts were paralleled by drastic decreases in mineralization degrees, as revealed ultrastructurally. In conclusion, cPLA2α may be regarded as a crucial co-factor contributing to AVIC mineralization in vitro, thus being an attractive potential target for designing novel therapeutic strategies aimed to counteract onset or progression of calcific aortic valve diseases.

Unusual ectopic ACTH syndrome in a patient with orbital neuroendocrine tumor, resulted false-positive outcome of BIPSS:a case report

BackgroundCushing’s syndrome has been described as a complex endocrine disorder characterized with high cortisol concentration. Correct and early diagnosis of Cushing’s syndrome is challenging. According to the latest guideline, bilateral inferior petrosal sinus sampling (BIPSS) is considered to be the gold standard for the differential diagnosis. However, in some unusual cases, this method may be false positive. Here, we presented a rare case of orbital neuroendocrine tumor secreting adrenocorticotrophic hormone with false positive inferior petrosal sinus sampling.Case presentationA 48-year-old woman was admitted to West China Hospital of Sichuan University, presenting with fatigue, whole body edema for 1 year, alopecia and skin pigmentation for 5 months. Hormonal profiles including plasma cortisol and adrenocorticotrophic hormone (ACTH) measurements and low-dose dexamethasone inhibition test suggested that the patient had Cushing’s syndrome. However, during tumor location phase, the results of high-dose dexamethasone inhibition test (HDDST) contradicted desmopressin (DDAVP) stimulation test. Thus, BIPSS was employed, and its results indicated a pituitary origin. Interestingly, MRI of sellar region showed an innocent pituitary but caught a serendipitous lesion in the lateral rectus muscle of left eye, which was later proved to be an orbital neuroendocrine tumor secreting ACTH by pathological and immunohistochemical results. ACTH level of the patients was < 0.1 ng/L and cortisol level was 51.61 nmol/L 1 week after surgery. At 24 months follow-up, the patient appeared stable with no complaints nor any symptoms of Cushing’s syndrome, including moon face, purple striate and central obesity. The patient’s life quality also improved significantly.ConclusionWe reported a rare case of endogenous Cushing’s syndrome due to ectopic ACTH secreting from an orbital neuroendocrine tumor. This unique case of orbital EAS suggests that orbital venous blood backflow, owning to abnormal anatomic structures, may possibly lead to false positive BIPSS results.

Restoration of HDAC2 and Nrf2 by andrographolide overcomes corticosteroid resistance in chronic obstructive pulmonary disease.

Corticosteroid resistance poses a major barrier to an effective anti-inflammatory therapy for chronic obstructive pulmonary disease (COPD). The present study aimed to investigate potential corticosteroid re-sensitization actions of andrographolide, a bioactive molecule from the herb Andrographis paniculata, in COPD models, particularly in peripheral blood mononuclear cells (PBMCs) from COPD patients. Corticosteroid sensitivity in PBMCs collected from COPD patients, or in human monocytic U937 cells exposed to cigarette smoke extract (CSE), was determined by measuring LPS-induced IL-8 production, in the presence and absence of andrographolide. The mechanisms of corticosteroid re-sensitization action of andrographolide were evaluated in a mouse cigarette smoke (CS)-induced acute lung injury model. Impaired inhibition of IL-8 production by dexamethasone was detected in PBMCs from COPD patients and in CSE-exposed U937 cells, together with reduced levels of nuclear factor erythroid 2-related factor 2 (Nrf2) and histone deacetylase-2 (HDAC2). In both PBMCs and CSE-exposed U937 cells, andrographolide restored dexamethasone inhibition of IL-8 production, accompanied by the up-regulation of Nrf2 and HDAC2 levels. In the U937 cells, andrographolide was able to block CSE-induced Akt and reduce the level of c-Jun. Besides, andrographolide also augmented dexamethasone actions on lowering total and neutrophil counts, cytokine levels, and oxidative damage markers in bronchoalveolar lavage fluid from CS-exposed mice. We report here for the first time a novel corticosteroid re-sensitization property of andrographolide in human PBMCs and provide mechanistic evidence to support clinical evaluation of andrographolide in reversing steroid resistance in COPD.

MON-200 Clinical Characterizations of Aldosterone- and Cortisol-Producing Adrenal Tumors in Primary Aldosteronism

Objective: Aldosterone- and cortisol-producing adrenal tumors (A/CPTs) are considered to be a subtype of primary aldosteronism (PA). The clinical characterizations of these tumors are still unclear, and they are often neglected by clinicians. The aim of this study was to summarize the clinical characterizations of these tumors to reduce the missed diagnosis. Methods: The clinical, imaging and pathological data of patients with PA admitted to our hospital from January 1, 2013 to December 31, 2016 was reviewed. All the PA patients with a combination of a positive aldosterone-to-renin ratio (ARR) and a positive captopril challenge test (CCT), in whom the dexamethasone inhibition test was performed as well, were included in our study. These patients were divided into two groups, A/CPTs group and simple PA group, according to the function of cortisol secretion. The data of the two groups were compared and analyzed with SPSS 23.0. P<0.05 was statistically significant. Results: There were 87 patients with PA included in our study, 32 of whom (36.8%) were diagnosed with A/CPTs. In these 32 A/CPTs patients, 31 patients (96.9%) were combined with subclinical Cushing syndrome. Compared to these in simple PA group (n=55), the patients in A/CPTs group (n=32) were elder (53.81±10.70 ys vs 48.42±10.17 ys, P=0.022), with larger diameter of adrenal tumors (1.50cm vs 1.15cm, P=0.001), higher fasting plasma glucose (5.33mmo/L vs 4.99mmol/L, P=0.047), higher serum cortisol levels and lower serum ACTH levels (all P<0.05). 24 patients in A/CPTs group and 23 patients in simple PA group underwent adrenalectomy. 6 patients (25.0%) in A/CPTs group and 3 patients (13.0%) in simple PA group received glucocorticoid replacement therapy after adrenalectomy. Conclusions:The prevalence of A/CPTs in PA is high. The patients with A/CPTs are mainly combined with subclinical Cushing syndrome, and prone to need glucocorticoid replacement therapy. Therefore, we recommend that all patients with PA should evaluate the function of cortisol secretion, and all patients with A/CPTs should be followed up closely after adrenalectomy to reduce the morbidity of adrenal insufficiency.

Dexamethasone synergizes with MCL-1 inhibition in multiple myeloma through suppression of S6 phosphorylation

The number of anti-cancer drugs that are approved for clinical use or in late-stage clinical trials for treatment of multiple myeloma is extensive and rapidly increasing. However, drug resistance and relapse after treatment are still very common problems. There is an unmet need for a strategy to identify logical combinations of (partially) successful drugs to reach synergistic effects. Testing all possible drug combinations and redefining pharmacodynamics for combination treatments is practically challenging. Therefore, we performed a lethality screen in three human multiple myeloma cell lines (HMCLs) in which we combined two drugs representing different drugs classes, including classical chemotherapeutics, proteasome inhibitors, pro-survival BCL-2 protein family inhibitors, HDAC inhibitors and corticosteroids to test for synergy. Of the twenty-eight combinations tested, seven showed synergistic effects in all three HMCLs. The combination of dexamethasone with the specific MCL-1 inhibitor S63845 was found to be the most potent, resulting in strong synergistic killing with average combination indexes of 0.3-0.5. In accordance with literature we observed a minor increase in dexamethasone-induced BIM mRNA and protein expression. Additional kinome analysis of HMCLs revealed a reduction in Akt kinase activity upon dexamethasone treatment. We did not observe downstream effects on nuclear FOXO1/3a levels or localization but did detect a great reduction in phosphorylation of ribosomal protein S6 on both serine 235/236 and 240/244 positions. Inhibition of S6 phosphorylation by a S6K1 inhibitor also had synergistic effects on cell death in combination with MCL-1 inhibition. This suggests that a S6K1 inhibitor might be used as a substitute of dexamethasone in the combinatorial treatment with MCL-1 inhibitors. In conclusion, we reveal a novel molecular mechanism mediated by Akt and S6 phosphorylation that is underlying synergy between dexamethasone and MCL-1 inhibition in multiple myeloma.

Analysis of prognostic factors in patients with refractory sudden sensorineural hearing loss

Objective:To explore the relationships between glucocorticoid (GC) sensitivity and the prognosis of refractory sudden sensorineural hearing loss (SSNHL), and to analyze the related factors being affected the prognosis of SSNHL. Method:Ninety-one refractory SSNHL patients were enrolled in the present investigation. Peripheral blood mononuclear cells (PBMCs) from the refractory SSNHL were extracted to conduct GC proliferation dexamethasone (DEX) inhibition experiments. All patients accepted comprehensive treatment with methylprednisolone. Result:Total effective rate was 40.66% in refractory SSNHL patients. Gender, number of affected ear, age, accompanying with vertigo, tinnitus or not and the procedure of methylprednisolone treatment were irrelevant to the efficacy. Only the inhibitory rate of DEX and the time from onset to visit were related to GC treatment effect, especially for inhibitory rate of DEX. The DEX inhibition rate of the effective group was higher than that of the ineffective group. Conclusion:DEX inhibition rate can predict GC sensitivity and prognosis of SSNHL. GC sensitivity and the time from onset to treatment are two important factors affecting the prognosis of refractory SSNHL patients..