Glucocorticoids Rapidly Activate cAMP Production via G\u3csub\u3eαs\u3c/sub\u3e to Initiate Non-Genomic Signaling That Contributes to One-Third of Their Canonical Genomic Effects

Glucocorticoids are widely used for the suppression of inflammation, but evidence is growing that they can have rapid, non-genomic actions that have been unappreciated. Diverse cell signaling effects have been reported for glucocorticoids, leading us to hypothesize that glucocorticoids alone can swiftly increase the 3′,5′-cyclic adenosine monophosphate (cAMP) production. We found that prednisone, fluticasone, budesonide, and progesterone each increased cAMP levels within 3 minutes without phosphodiesterase inhibitors by measuring real-time cAMP dynamics using the cAMP difference detector in situ assay in a variety of immortalized cell lines and primary human airway smooth muscle (HASM) cells. A membrane- impermeable glucocorticoid showed similarly rapid stimulation of cAMP, implying that responses are initiated at the cell surface. siRNA knockdown of Gαs virtually eliminated glucocorticoidstimulated cAMP responses, suggesting that these drugs activate the cAMP production via a G protein-coupled receptor. Estradiol had small effects on cAMP levels but G protein estrogen receptor antagonists had little effect on responses to any of the glucocorticoids tested. The genomic and non-genomic actions of budesonide were analyzed by RNA-Seq analysis of 24 hours treated HASM, with and without knockdown of Gαs. A 140-gene budesonide signature was identified, of which 48 genes represent a non-genomic signature that requires Gαs signaling. Collectively, this non-genomic cAMP signaling modality contributes to one-third of the gene expression changes induced by glucocorticoid treatment and shifts the view of how this important class of drugs exerts its effect

Large para-testicular intra-scrotal malignant peripheral nerve sheath tumor managed with radical penectomy: A case report

Neurofibromatosis 1 is a relatively rare genetic disease characterized by widespread neurofibromas originating from the peripheral nervous system. Most growths are benign, but some carry a risk of transformation to malignant peripheral nerve sheath tumors. Although these growths can be found anywhere in the body, they are rarely found in the male external genitalia. This report discusses a case of a 25-year-old male patient with neurofibromatosis 1 presenting with a scrotal mass found to have a very large para-testicular intra-scrotal malignant peripheral nerve sheath tumor that required testicle-sparing radical penectomy

PDE8 Is Expressed in Human Airway Smooth Muscle and Selectively Regulates cAMP Signaling by β2-Adrenergic Receptors and Adenylyl Cyclase 6

Two cAMP signaling compartments centered on adenylyl cyclase (AC) exist in human airway smooth muscle (HASM) cells, one containing β2-adrenergic receptor AC6 and another containing E prostanoid receptor AC2. We hypothesized that different PDE isozymes selectively regulate cAMP signaling in each compartment. According to RNA-sequencing data, 18 of 24 PDE genes were expressed in primary HASM cells derived from age- and sex-matched donors with and without asthma. PDE8A was the third most abundant of the cAMP-degrading PDE genes, after PDE4A and PDE1A. Knockdown of PDE8A using shRNA evoked twofold greater cAMP responses to 1 μM forskolin in the presence of 3-isobutyl-1-methylxanthine. Overexpression of AC2 did not alter this response, but overexpression of AC6 increased cAMP responses an additional 80%. We examined cAMP dynamics in live HASM cells using a fluorescence sensor. PF-04957325, a PDE8-selective inhibitor, increased basal cAMP concentrations by itself, indicating a significant basal level of cAMP synthesis. In the presence of an AC inhibitor to reduce basal signaling, PF-04957325 accelerated cAMP production and increased the inhibition of cell proliferation induced by isoproterenol, but it had no effect on cAMP concentrations or cell proliferation regulated by prostaglandin E2. Lipid raft fractionation of HASM cells revealed PDE8A immunoreactivity in buoyant fractions containing caveolin-1 and AC5/6 immunoreactivity. Thus, PDE8 is expressed in lipid rafts of HASM cells, where it specifically regulates β2-adrenergic receptor AC6 signaling without effects on signaling by the E prostanoid receptors 2/4-AC2 complex. In airway diseases such as asthma and chronic obstructive pulmonary disease, PDE8 may represent a novel therapeutic target to modulate HASM responsiveness and airway remodeling

PDE8 is Expressed in Human Airway Smooth Muscle and Selectively Regulates cAMP Signaling by β 2 AR-AC6

Two cAMP signaling compartments centering around adenylyl cyclase (AC) exist in human airway smooth muscle (HASM) cells, one containing ß2AR-AC6 and another containing E prostanoid receptors (EPR)-AC2. We hypothesized that different phosphodiesterase (PDE) isozymes selectively regulate cAMP signaling in each compartment. According to RNA-seq data, 18 of 24 PDE genes were expressed in primary HASM cells derived from age- and gender-matched donors with and without asthma. PDE8A was the third most abundant of the cAMP-degrading PDE genes, after PDE4A and PDE1A. Knockdown of PDE8A using shRNA evoked 2-fold greater cAMP responses to 1 DM forskolin in the presence of IBMX. Overexpression of AC2 did not alter this response, but overexpression of AC6 increased cAMP responses an additional 80%. We examined cAMP dynamics in live HASM cells using a fluorescent sensor. PF-04957325, a PDE8-selective inhibitor, increased basal cAMP levels by itself, indicating a significant basal level of cAMP synthesis. In the presence of an AC inhibitor to reduce basal signaling, PF-04957325 accelerated cAMP production and increased the inhibition of cell proliferation induced by isoproterenol, but had no effect on cAMP levels or cell proliferation regulated by PGE2. Lipid raft fractionation of HASM cells revealed PDE8A immunoreactivity in buoyant fractions containing caveolin-1 and AC5/6 immunoreactivity. Thus, PDE8 is expressed in lipid rafts of HASM cells where it specifically regulates ß2AR-AC6 signaling without effects on signaling by the EP2/4R-AC2 complex. In airway diseases such as asthma and COPD, PDE8 may represent a novel therapeutic target to modulate HASM responsiveness and airway remodeling

Medicare Under Age 65 and Medicaid Patients Have Poorer Bowel Preparations: Implications for Recommendations for an Early Repeat Colonoscopy

Colonoscopy is performed on patients across a broad spectrum of demographic characteristics. These characteristics may aggregate by patient insurance provider and influence bowel preparation quality and the prevalence of adenomas. The purpose of this study was to evaluate the association of insurance status and suboptimal bowel preparation, recommendation for an early repeat colonoscopy due to suboptimal bowel preparation, adenoma detection rate (ADR), and advanced ADR (AADR)