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Scholl UI, Abriola L, Zhang CB, Reimer EN, Plummer M, Kazmierczak BI, Zhang JH, Hoyer D, Merkel JS, Wang WH, Lifton RP
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Macrolides selectively inhibit mutant KCNJ5 potassium channels that cause aldosterone-producing adenoma

JOURNAL OF CLINICAL INVESTIGATION 2017 JUN 30; 127(7):2739-2750
Aldosterone-producing adenomas (APAs) are benign tumors of the adrenal gland that constitutively produce the salt-retaining steroid hormone aldosterone and cause millions of cases of severe hypertension worldwide. Either of 2 somatic mutations in the potassium channel KCNJ5 (G151R and L168R, hereafter referred to as KCNJ5(MUT)) in adrenocortical cells account for half of APAs worldwide. These mutations alter channel selectivity to allow abnormal Na+ conductance, resulting in membrane depolarization, calcium influx, aldosterone production, and cell proliferation. Because APA diagnosis requires a difficult invasive procedure, patients often remain undiagnosed and inadequately treated. Inhibitors of KCNJ5(MUT) could allow noninvasive diagnosis and therapy of APAs carrying KCNJ5 mutations. Here, we developed a high-throughput screen for rescue of KCNJ5(MUT)-induced lethality and identified a series of macrolide antibiotics, including roxithromycin, that potently inhibit KCNJ5(MUT), but not KCNJ5(WT). Electrophysiology demonstrated direct KCNJ5(MUT) inhibition. In human aldosterone-producing adrenocortical cancer cell lines, roxithromycin inhibited KCNJ5(MUT)-induced induction of CYP11B2 (encoding aldosterone synthase) expression and aldosterone production. Further exploration of macrolides showed that KCNJ5(MUT) was similarly selectively inhibited by idremcinal, a macrolide motilin receptor agonist, and by synthesized macrolide derivatives lacking antibiotic or motilide activity. Macrolide-derived selective KCNJ5(MUT) inhibitors thus have the potential to advance the diagnosis and treatment of APAs harboring KCNJ5(MUT).
Zhong HX, Tong L, Gu N, Gao F, Lu YC, Xie RG, Liu JJ, Li X, Bergeron R, Pomeranz LE, Mackie K, Wang F, Luo CX, Ren Y, Wu SX, Xie ZC, Xu L, Li JL, Dong HL, Xiong LZ, Zhang X
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Endocannabinoid signaling in hypothalamic circuits regulates arousal from general anesthesia in mice

JOURNAL OF CLINICAL INVESTIGATION 2017 JUN 1; 127(6):2295-2309
Consciousness can be defined by two major attributes: awareness of environment and self, and arousal, which reflects the level of awareness. The return of arousal after general anesthesia presents an experimental tool for probing the neural mechanisms that control consciousness. Here we have identified that systemic or intracerebral injection of the cannabinoid CB1 receptor (CB1R) antagonist AM281 into the dorsomedial nucleus of the hypothalamus (DMH) - but not the adjacent perifornical area (Pef) or the ventrolateral preoptic nucleus of the hypothalamus (VLPO) - accelerates arousal in mice recovering from general anesthesia. Anesthetics selectively activated endocannabinoid (eCB) signaling at DMH glutamatergic but not GABAergic synapses, leading to suppression of both glutamatergic DMH-Pef and GABAergic DMH-VLPO projections. Deletion of CB1R from widespread cerebral cortical or prefrontal cortical (PFC) glutamatergic neurons, including those innervating the DMH, mimicked the arousal-accelerating effects of AM281. In contrast, CB1R deletion from brain GABAergic neurons or hypothalamic glutamatergic neurons did not affect recovery time from anesthesia. Inactivation of PFC-DMH, DMH-VLPO, or DMH-Pef projections blocked AM281-accelerated arousal, whereas activation of these projections mimicked the effects of AM281. We propose that decreased eCB signaling at glutamatergic terminals of the PFC-DMH projection accelerates arousal from general anesthesia through enhancement of the excitatory DMH-Pef projection, the inhibitory DMH-VLPO projection, or both.
Hoffman LK, Ghias MH, Garg A, Hamzavi IH, Alavi A, Lowes MA
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Major gaps in understanding and treatment of hidradenitis suppurativa

SEMINARS IN CUTANEOUS MEDICINE AND SURGERY 2017 JUN; 36(2):86-92
Hidradenitis suppurativa (HS) is a complex dermatological disease characterized by recurrent painful nodules and suppuration in areas such as the axilla and groin.The disease is poorly understood and treatment is not satisfactory. In October 2016, the Canadian and United States Hidradenitis Suppurativa Foundations organized the inaugural Symposium on Hidradenitis Suppurativa Advances (SHSA) in Toronto, Canada.This meeting brought together experts from Canada, the United States, and Europe to discuss the latest advances in HS.After this important event, we considered that it would be helpful to outline current HS knowledge and to identify important gaps in treatment and research in order to move forward more efficiently. This paper briefly summarizes current knowledge in key areas including epidemiology, clinical presentation and morphological classification, natural history and prognosis, genotype-phenotype correlations, clinico-pathological correlation, pathogenesis, optimal treatment and outcome measures. General and initial suggestions for addressing these gaps are presented. (C) 2017 Frontline Medical Communications
Nirschl CJ, Suarez-Farinas M, Izar B, Prakadan S, Dannenfelser R, Tirosh I, Liu Y, Zhu Q, Devi KSP, Carroll SL, Chau D, Rezaee M, Kim TG, Huang RQ, Fuentes-Duculan J, Song-Zhao GX, Gulati N, Lowes MA, King SL, Quintana FJ, Lee YS, Krueger JG, Sarin KY, Yoon CH, Garraway L, Regev A, Shalek AK, Troyanskaya O, Anandasabapathy N
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IFN gamma-Dependent Tissue-Immune Homeostasis Is Co-opted in the Tumor Microenvironment

CELL 2017 JUN 29; 170(1):127-141.e15
Homeostatic programs balance immune protection and self-tolerance. Such mechanisms likely impact autoimmunity and tumor formation, respectively. How homeostasis is maintained and impacts tumor surveillance is unknown. Here, we find that different immune mononuclear phagocytes share a conserved steady-state program during differentiation and entry into healthy tissue. IFN gamma is necessary and sufficient to induce this program, revealing a key instructive role. Remarkably, homeostatic and IFN gamma-dependent programs enrich across primary human tumors, including melanoma, and stratify survival. Single-cell RNA sequencing (RNA-seq) reveals enrichment of homeostatic modules in monocytes and DCs from human metastatic melanoma. Suppressor-of-cytokine-2 (SOCS2) protein, a conserved program transcript, is expressed by mononuclear phagocytes infiltrating primary melanoma and is induced by IFN gamma. SOCS2 limits adaptive anti-tumoral immunity and DC-based priming of T cells in vivo, indicating a critical regulatory role. These findings link immune homeostasis to key determinants of anti-tumoral immunity and escape, revealing co-opting of tissue-specific immune development in the tumor microenvironment.
Moens L, Van Eyck L, Jochmans D, Mitera T, Frans G, Bossuyt X, Matthys P, Neyts J, Ciancanelli M, Zhang SY, Gijsbers R, Casanova JL, Boisson-Dupuis S, Meyts I, Liston A
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A novel kindred with inherited STAT2 deficiency and severe viral illness

JOURNAL OF ALLERGY AND CLINICAL IMMUNOLOGY 2017 JUN; 139(6):1995-1997.e9
Bergamin E, Sarvan S, Malette J, Eram MS, Yeung S, Mongeon V, Joshi M, Brunzelle JS, Michaels SD, Blais A, Vedadi M, Couture JF
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Molecular basis for the methylation specificity of ATXR5 for histone H3

NUCLEIC ACIDS RESEARCH 2017 JUN 20; 45(11):6375-6387
In plants, the histone H3.1 lysine 27 (H3K27) mono-methyltransferases ARABIDOPSIS TRITHORAX RELATED PROTEIN 5 and 6 (ATXR5/6) regulate heterochromatic DNA replication and genome stability. Our initial studies showed that ATXR5/6 discriminate between histone H3 variants and preferentially methylate K27 on H3.1. In this study, we report three regulatory mechanisms contributing to the specificity of ATXR5/6. First, we show that ATXR5 preferentially methylates the R/F-K*-S/C-G/A-P/C motif with striking preference for hydrophobic and aromatic residues in positions flanking this core of five amino acids. Second, we demonstrate that post-transcriptional modifications of residues neighboring K27 that are typically associated with actively transcribed chromatin are detrimental to ATXR5 activity. Third, we show that ATXR5 PHD domain employs a narrow binding pocket to selectively recognize unmethylated K4 of histone H3. Finally, we demonstrate that deletion or mutation of the PHD domain reduces the catalytic efficiency (kcat/Km of AdoMet) of ATXR5 up to 58-fold, highlighting the multifunctional nature of ATXR5 PHD domain. Overall, our results suggest that several molecular determinants regulate ATXR5/6 methyltransferase activity and epigenetic inheritance of H3.1 K27me1 mark in plants.
Eslami N, Tavakol M, Mesdaghi M, Gharegozlou M, Casanova JL, Puel A, Okada S, Arshi S, Bemanian MH, Fallahpour M, Molatefi R, Seif F, Zoghi S, Rezaei N, Nabavi M
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A GAIN-OF-FUNCTION MUTATION OF STAT1: A NOVEL GENETIC FACTOR CONTRIBUTING TO CHRONIC MUCOCUTANEOUS CANDIDIASIS

ACTA MICROBIOLOGICA ET IMMUNOLOGICA HUNGARICA 2017 JUN; 64(2):191-201
Heterozygous gain-of-function (GOF) mutations in the signal transducer and activator of transcription 1 (STAT1) have increasingly been identified as a genetic cause of autosomal-dominant (AD) chronic mucocutaneous candidiasis (CMC). In this article, we describe a 33-year-old man who experienced chronic refractory candidiasis, recurrent otitis media, and pneumonia resulting in bronchiectasis, severe oral and esophageal candidiases with strictures associated with hypothyroidism and immune hemolytic anemia. His son also suffered from persistent candidiasis, chronic diarrhea, poor weight gain, and pneumonia that resulted in his demise because of sepsis. The immunological workup showed that an inverse CD4/CD8 ratio and serum immunoglobulins were all within normal ranges. The laboratory data revealed failure in response to Candida lymphocyte transformation test. In addition, by Sanger sequencing method, we found a heterozygous mutation, Thr385Met (T385M), located in the DNA-binding domain of STAT1, which was previously shown to be GOF. These findings illustrate the broad and variable clinical phenotype of heterozygous STAT1 GOF mutations. However, more clinical information and phenotype-genotype studies are required to define the clinical phenotype caused by AD STAT1 GOF.
Shapiro AJ, Darmon SK, Barad DH, Albertini DF, Gleicher N, Kushnir VA
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Effect of race and ethnicity on utilization and outcomes of assisted reproductive technology in the USA

REPRODUCTIVE BIOLOGY AND ENDOCRINOLOGY 2017 JUN 8; 15(?):? Article 44
Background: The purpose of this study was to determine the utilization and live birth rates of assisted reproductive technology (ART) modalities among various racial and ethnic groups in recent years. Methods: We reviewed ART data reported to the Society for Assisted Reproductive Technologies Clinic Outcome Reporting System (SART CORS) for autologous ART and third-party ART (3ART) cycles which involved donor oocytes, sperm, embryos and gestational carrier, performed in the U.S. between 2004 and 2013. To gauge demand by various racial/ethnic groups for ART services, we examined fertility rates and demographics of the entire U.S. birth cohort over the same time interval. Results: Of 1,132,844 autologous ART cycles 335,462 resulted in a live birth (29.6%). An additional, 217,030 3ART cycles resulted in 86,063 live births (39.7%). Hispanic and Black women demonstrated high fertility and lower utilization rates of autologous ART and 3ART. Caucasian and Asian women exhibited lower fertility rates and higher autologous ART and 3ART utilization. Autologous ART resulted in higher live birth rates among Caucasian and Hispanic women and lower rates among Asian and especially Black women. 3ART improved live birth rates in all races/ethnicities, though Black women experienced lower live birth rates with most modalities. Spontaneous abortion rates were higher among Black women following autologous ART and some 3ART modalities than those among Caucasian women. Conclusion: Utilization of ART is inversely related to fertility rates. Autologous ART produces lower live birth rates among Asian and Black women. 3ART results in relatively low live birth rates among Black women.
Simunovic M, Manneville JB, Renard HF, Evergren E, Raghunathan K, Bhatia D, Kenworthy AK, Voth GA, Prost J, McMahon HT, Johannes L, Bassereau P, Callan-Jones A
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Friction Mediates Scission of Tubular Membranes Scaffolded by BAR Proteins

CELL 2017 JUN 29; 170(1):?
Membrane scission is essential for intracellular trafficking. While BAR domain proteins such as endophilin have been reported in dynamin-independent scission of tubular membrane necks, the cutting mechanism has yet to be deciphered. Here, we combine a theoretical model, in vitro, and in vivo experiments revealing how protein scaffolds may cut tubular membranes. We demonstrate that the protein scaffold bound to the underlying tube creates a frictional barrier for lipid diffusion; tube elongation thus builds local membrane tension until the membrane undergoes scission through lysis. We call this mechanism friction-driven scission (FDS). In cells, motors pull tubes, particularly during endocytosis. Through reconstitution, we show that motors not only can pull out and extend protein-scaffolded tubes but also can cut them by FDS. FDS is generic, operating even in the absence of amphipathic helices in the BAR domain, and could in principle apply to any high-friction protein and membrane assembly.
Musante V, Li L, Kanyo J, Lam TT, Colangelo CM, Cheng SK, Brody AH, Greengard P, Le Novere N, Nairn AC
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Reciprocal regulation of ARPP-16 by PKA and MAST3 kinases provides a cAMP-regulated switch in protein phosphatase 2A inhibition

ELIFE 2017 JUN 14; 6(?):? Article e24998
ARPP-16, ARPP-19, and ENSA are inhibitors of protein phosphatase PP2A. ARPP-19 and ENSA phosphorylated by Greatwall kinase inhibit PP2A during mitosis. ARPP-16 is expressed in striatal neurons where basal phosphorylation by MAST3 kinase inhibits PP2A and regulates key components of striatal signaling. The ARPP-16/19 proteins were discovered as substrates for PKA, but the function of PKA phosphorylation is unknown. We find that phosphorylation by PKA or MAST3 mutually suppresses the ability of the other kinase to act on ARPP-16. Phosphorylation by PKA also acts to prevent inhibition of PP2A by ARPP-16 phosphorylated by MAST3. Moreover, PKA phosphorylates MAST3 at multiple sites resulting in its inhibition. Mathematical modeling highlights the role of these three regulatory interactions to create a switch-like response to cAMP. Together, the results suggest a complex antagonistic interplay between the control of ARPP-16 by MAST3 and PKA that creates a mechanism whereby cAMP mediates PP2A disinhibition.