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1. Vascular endothelial growth factor promotes atrial arrhythmias by inducing acute intercalated disk remodeling

Author

Louisa Mezache, Heather L. Struckman, Amara Greer-Short, Stephen Baine, Sándor Györke, Przemysław B. Radwański, Thomas J. Hund, and Rengasayee Veeraraghavan

Subjects
Medicine, Science
Abstract

Abstract Atrial fibrillation (AF) is the most common arrhythmia and is associated with inflammation. AF patients have elevated levels of inflammatory cytokines known to promote vascular leak, such as vascular endothelial growth factor A (VEGF). However, the contribution of vascular leak and consequent cardiac edema to the genesis of atrial arrhythmias remains unknown. Previous work suggests that interstitial edema in the heart can acutely promote ventricular arrhythmias by disrupting ventricular myocyte intercalated disk (ID) nanodomains rich in cardiac sodium channels (NaV1.5) and slowing cardiac conduction. Interestingly, similar disruption of ID nanodomains has been identified in atrial samples from AF patients. Therefore, we tested the hypothesis that VEGF-induced vascular leak can acutely increase atrial arrhythmia susceptibility by disrupting ID nanodomains and slowing atrial conduction. Treatment of murine hearts with VEGF (30–60 min, at clinically relevant levels) prolonged the electrocardiographic P wave and increased susceptibility to burst pacing-induced atrial arrhythmias. Optical voltage mapping revealed slower atrial conduction following VEGF treatment (10 ± 0.4 cm/s vs. 21 ± 1 cm/s at baseline, p

Published
2020
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2. The Cx43 Carboxyl-Terminal Mimetic Peptide αCT1 Protects Endothelial Barrier Function in a ZO1 Binding-Competent Manner

Author

Randy E. Strauss, Louisa Mezache, Rengasayee Veeraraghavan, and Robert G. Gourdie

Subjects
Cx43, Zonula Occludens 1, barrier function, tight junctions, adherens junctions, actin cytoskeleton, Microbiology, QR1-502
Abstract

The Cx43 carboxyl-terminus (CT) mimetic peptide, αCT1, originally designed to bind to Zonula Occludens 1 (ZO1) and thereby inhibit Cx43/ZO1 interaction, was used as a tool to probe the role of Cx43/ZO1 association in regulation of epithelial/endothelial barrier function. Using both in vitro and ex vivo methods of barrier function measurement, including Electric Cell-Substrate Impedance Sensing (ECIS), a TRITC-dextran Transwell permeability assay, and a FITC-dextran cardiovascular leakage protocol involving Langendorff-perfused mouse hearts, αCT1 was found to protect the endothelium from thrombin-induced breakdown in cell–cell contacts. Barrier protection was accompanied by significant remodeling of the F-actin cytoskeleton, characterized by a redistribution of F-actin away from the cytoplasmic and nuclear regions of the cell, towards the endothelial cell periphery, in association with alterations in cellular chiral orientation distribution. In line with observations of increased cortical F-actin, αCT1 upregulated cell–cell border localization of endothelial VE-cadherin, the tight junction protein Zonula Occludens 1 (ZO1), and the Gap Junction Protein (GJ) Connexin43 (Cx43). A ZO1 binding-incompetent variant of αCT1, αCT1-I, indicated that these effects on barrier function and barrier-associated proteins, were likely associated with Cx43 CT sequences retaining ability to interact with ZO1. These results implicate the Cx43 CT and its interaction with ZO1, in the regulation of endothelial barrier function, while revealing the therapeutic potential of αCT1 in the treatment of vascular edema.

Published
2021
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3. STIM1 ablation impairs exercise-induced physiological cardiac hypertrophy and dysregulates autophagy in mouse hearts

Author

Ingrid M. Bonilla, Stephen Baine, Anastasia Pokrass, Juan Ignacio Elio Mariángelo, Anuradha Kalyanasundaram, Vladimir Bogdanov, Louisa Mezache, Galina Sakuta, Casey M. Beard, Andriy Belevych, Svetlana Tikunova, Radmila Terentyeva, Dmitry Terentyev, Jonathan Davis, Rengasayee Veeraraghavan, Cynthia A. Carnes, and Sandor Györke

Subjects
Physiology, Physiology (medical)
Abstract

Store-operated Ca2+ entry (SOCE) has been implicated in pathological cardiac hypertrophy; however, its role in physiological hypertrophy is unknown. Here we report that SOCE is also essential for physiological cardiac hypertrophy and functional adaptations in response to endurance exercise. These adaptations were associated with activation of AKT/mTOR pathway and curtailed cardiac autophagy and degeneration. Thus, SOCE is a common mechanism and an important bifurcation point for signaling paths involved in physiological and pathological hypertrophy.

Published
2023
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4. Post-intervention Status in Patients With Refractory Myasthenia Gravis Treated With Eculizumab During REGAIN and Its Open-Label Extension

Author

Mantegazza, R., Wolfe, G. I., Muppidi, S., Wiendl, H., Fujita, K. P., O'Brien, F. L., Booth, H. D. E., Howard, J. F., Claudio Gabriel Mazia, Miguel, Wilken, Fabio, Barroso, Juliet, Saba, Marcelo, Rugiero, Mariela, Bettini, Marcelo, Chaves, Gonzalo, Vidal, Alejandra Dalila Garcia, Jan De Bleecker, Guy Van den Abeele, Kathy de Koning, Katrien De Mey, Rudy, Mercelis, Délphine, Mahieu, Linda, Wagemaekers, Philip Van Damme, Annelies, Depreitere, Caroline, Schotte, Charlotte, Smetcoren, Olivier, Stevens, Sien Van Daele, Nicolas, Vandenbussche, Annelies, Vanhee, Sarah, Verjans, Jan, Vynckier, Ann, D'Hont, Petra, Tilkin, Alzira Alves de Siqueira Carvalho, Igor Dias Brockhausen, David, Feder, Daniel, Ambrosio, Gabor Lovasamela César, Ana Paula Melo, Renata Martins Ribeiro, Rosana, Rocha, Bruno Bezerra Rosa, Thabata, Veiga, Luiz Augusto da Silva, Murilo Santos Engel, Jordana Gonçalves Geraldo, Maria da Penha Ananias Morita, Erica Nogueira Coelho, Gabriel, Paiva, Marina, Pozo, Natalia, Prando, Debora Dada Martineli Torres, Cristiani Fernanda Butinhao, Gustavo, Duran, Tomás Augusto Suriane Fialho, Tamires Cristina Gomes da Silva, Luiz Otavio Maia Gonçalves, Lucas Eduardo Pazetto, Luciana Renata Cubas Volpe, Luciana Souza Duca, Maurício AndréGheller Friedrich, Alexandre, Guerreiro, Henrique, Mohr, Maurer Pereira Martins, Daiane da Cruz Pacheco, Luciana, Ferreira, Ana Paula Macagnan, Graziela, Pinto, Aline de Cassia Santos, Acary Souza Bulle Oliveira, Ana Carolina Amaral de Andrade, Marcelo, Annes, Liene Duarte Silva, Valeria Cavalcante Lino, Wladimir, Pinto, Natália, Assis, Fernanda, Carrara, Carolina, Miranda, Iandra, Souza, Patrícia, Fernandes, Zaeem, Siddiqi, Cecile, Phan, Jeffrey, Narayan, Derrick, Blackmore, Ashley, Mallon, Rikki, Roderus, Elizabeth, Watt, Stanislav, Vohanka, Josef, Bednarik, Magda, Chmelikova, Marek, Cierny, Stanislava, Toncrova, Jana, Junkerova, Barbora, Kurkova, Katarina, Reguliova, Olga, Zapletalova, Jiri, Pitha, Iveta, Novakova, Michaela, Tyblova, Ivana, Jurajdova, Marcela, Wolfova, Henning, Andersen, Thomas, Harbo, Lotte, Vinge, Susanne, Krogh, Anita, Mogensen, John, Vissing, Joan, Højgaard, Nanna, Witting, Anne Mette Ostergaard Autzen, Jane, Pedersen, Juha-Pekka, Erälinna, Mikko, Laaksonen, Olli, Oksaranta, Tuula, Harrison, Jaana, Eriksson, Csilla, Rozsa, Melinda, Horvath, Gabor, Lovas, Judit, Matolcsi, Gedeonne, Jakab, Gyorgyi, Szabo, Brigitta, Szabadosne, Laszlo, Vecsei, Livia, Dezsi, Edina, Varga, Monika, Konyane, Antonini, Giovanni, Antonella Di Pasquale, Garibaldi, Matteo, Morino, Stefania, Troili, Fernanda, Fionda, Laura, Amelia, Evoli, Paolo Emilio Alboini, Valentina, D'Amato, Raffaele, Iorio, Inghilleri, Maurizio, Frasca, Vittorio, Elena, Giacomelli, Gori, MARIA CRISTINA, Diego, Lopergolo, Onesti, Emanuela, Maria, Gabriele, Francesco, Saccà, Alessandro, Filla, Teresa, Costabile, Enrico, Marano, Angiola, Fasanaro, Angela, Marsili, Giorgia, Puorro, Carlo, Antozzi, Silvia, Bonanno, Giorgia, Camera, Alberta, Locatelli, Lorenzo, Maggi, Maria, Pasanisi, Angela, Campanella, Akiyuki, Uzawa, Tetsuya, Kanai, Naoki, Kawaguchi, Masahiro, Mori, Yoko, Kaneko, Akiko, Kanzaki, Eri, Kobayashi, Hiroyuki, Murai, Katsuhisa, Masaki, Dai, Matsuse, Takuya, Matsushita, Taira, Uehara, Misa, Shimpo, Maki, Jingu, Keiko, Kikutake, Yumiko, Nakamura, Yoshiko, Sano, Kimiaki, Utsugisawa, Yuriko, Nagane, Ikuko, Kamegamori, Tomoko, Tsuda, Yuko, Fujii, Kazumi, Futono, Yukiko, Ozawa, Aya, Mizugami, Yuka, Saito, Makoto, Samukawa, Hidekazu, Suzuki, Miyuki, Morikawa, Sachiko, Kamakura, Eriko, Miyawaki, Meinoshin, Okumura, Soichiro, Funaka, Tomohiro, Kawamura, Masayuki, Nakamori, Masanori, Takahashi, Namie, Taichi, Tomoya, Hasuike, Eriko, Higuchi, Hisako, Kobayashi, Kaori, Osakada, Hirokazu, Shiraishi, Teiichiro, Miyazaki, Masakatsu, Motomura, Akihiro, Mukaino, Shunsuke, Yoshimura, Shizuka, Asada, Seiko, Yoshida, Shoko, Amamoto, Tomomi, Kobashikawa, Megumi, Koga, Maeda, Yasuko, Kazumi, Takada, Mihoko, Takada, Masako, Tsurumaru, Yumi, Yamashita, Yasushi, Suzuki, Tetsuya, Akiyama, Koichi, Narikawa, Ohito, Tano, Kenichi, Tsukita, Rikako, Kurihara, Fumie, Meguro, Yusuke, Fukuda, Miwako, Sato, Tomihiro, Imai, Emiko, Tsuda, Shun, Shimohama, Takashi, Hayashi, Shin, Hisahara, Jun, Kawamata, Takashi, Murahara, Masaki, Saitoh, Shuichiro, Suzuki, Daisuke, Yamamoto, Yoko, Ishiyama, Naoko, Ishiyama, Mayuko, Noshiro, Rumi, Takeyama, Kaori, Uwasa, Ikuko, Yasuda, Anneke van der Kooi, Marianne de Visser, Tamar, Gibson, Byung-Jo, Kim, Chang Nyoung Lee, Yong Seo Koo, Hung Youl Seok, Hoo Nam Kang, Hyejin, Ra, Byoung Joon Kim, Eun Bin Cho, Misong, Choi, Hyelim, Lee, Ju-Hong, Min, Jinmyoung, Seok, Jieun, Lee, Da Yoon Koh, Juyoung, Kwon, Sangae, Park, Eun Haw Choi, Yoon-Ho, Hong, So-Hyun, Ahn, Dae Lim Koo, Jae-Sung, Lim, Chae Won Shin, Ji Ye Hwang, Miri, Kim, Seung Min Kim, Ha-Neul, Jeong, Jinwoo, Jung, Yool-Hee, Kim, Hyung Seok Lee, Ha Young Shin, Eun Bi Hwang, Miju, Shin, Carlos, Casasnovas, Maria Antonia Alberti Aguilo, Christian, Homedes-Pedret, Natalia Julia Palacios, Laura Diez Porras, Valentina Velez Santamaria, Ana, Lazaro, Josep Gamez Carbonell, Pilar, Sune, Maria Salvado Figueras, Gisela, Gili, Gonzalo, Mazuela, Isabel, Illa, Elena Cortes Vicente, Jordi, Diaz-Manera, Luis Antonio Querol Gutiérrez, Ricardo Rojas Garcia, Nuria, Vidal, Elisabet, Arribas-Ibar, Exuperio Diez Tejedor, Pilar Gomez Salcedo, Mireya, Fernandez-Fournier, Pedro Lopez Ruiz, Francisco Javier Rodriguez de Rivera, Maria, Sastre, Fredrik, Piehl, Albert, Hietala, Lena, Bjarbo, Ihsan, Sengun, Arzu, Meherremova, Pinar, Ozcelik, Bengu, Balkan, Celal, Tuga, Muzeyyen, Ugur, Sevim, Erdem-Ozdamar, Can Ebru Bekircan-Kurt, Nazire Pinar Acar, Ezgi, Yilmaz, Yagmur, Caliskan, Gulsah, Orsel, Husnu, Efendi, Seda, Aydinlik, Hakan, Cavus, Ayse, Kutlu, Gulsah, Becerikli, Cansu, Semiz, Ozlem, Tun, Murat, Terzi, Baki, Dogan, Musa Kazim Onar, Sedat, Sen, Tugce Kirbas Cavdar, Adife, Veske, Fiona, Norwood, Aikaterini, Dimitriou, Jakit, Gollogly, Mohamed, Mahdi-Rogers, Arshira, Seddigh, Giannis, Sokratous, Gal, Maier, Faisal, Sohail, Saiju, Jacob, Girija, Sadalage, Pravin, Torane, Claire, Brown, Amna, Shah, Sivakumar, Sathasivam, Heike, Arndt, Debbie, Davies, Dave, Watling, Anthony, Amato, Thomas, Cochrane, Mohammed, Salajegheh, Kristen, Roe, Katherine, Amato, Shirli, Toska, Nicholas, Silvestri, Kara, Patrick, Karen, Zakalik, Jonathan, Katz, Robert, Miller, Marguerite, Engel, Dallas, Forshew, Elena, Bravver, Benjamin, Brooks, Mohammed, Sanjak, Sarah, Plevka, Maryanne, Burdette, Scott, Cunningham, Megan, Kramer, Joanne, Nemeth, Clara, Schommer, Tierney, Scott, Vern, Juel, Jeffrey, Guptill, Lisa, Hobson-Webb, Janice, Massey, Kate, Beck, Donna, Carnes, John, Loor, Amanda, Anderson, Robert, Pascuzzi, Cynthia, Bodkin, John, Kincaid, Riley, Snook, Sandra, Guingrich, Angela, Micheels, Vinay, Chaudhry, Andrea, Corse, Betsy, Mosmiller, Andrea, Kelley, Doreen, Ho, Jayashri, Srinivasan, Michal, Vytopil, Jordan, Jara, Nicholas, Ventura, Cynthia, Carter, Craig, Donahue, Carol, Herbert, Stephanie, Scala, Elaine, Weiner, Sharmeen, Alam, Jonathan, Mckinnon, Laura, Haar, Naya, Mckinnon, Karan, Alcon, Kaitlyn, Mckenna, Nadia, Sattar, Kevin, Daniels, Dennis, Jeffery, Miriam, Freimer, Joseph Chad Hoyle, John, Kissel, Julie, Agriesti, Sharon, Chelnick, Louisa, Mezache, Colleen, Pineda, Filiz, Muharrem, Chafic, Karam, Julie, Khoury, Tessa, Marburger, Harpreet, Kaur, Diana, Dimitrova, James, Gilchrist, Brajesh, Agrawal, Mona, Elsayed, Stephanie, Kohlrus, Angela, Ardoin, Taylor, Darnell, Laura, Golden, Barbara, Lokaitis, Jenna, Seelbach, Neelam, Goyal, Sarada, Sakamuri, Yuen, T So, Shirley, Paulose, Sabrina, Pol, Lesly, Welsh, Ratna, Bhavaraju-Sanka, Alejandro Tobon Gonzalez, Lorraine, Dishman, Floyd, Jones, Anna, Gonzalez, Patricia, Padilla, Amy, Saklad, Marcela, Silva, Sharon, Nations, Jaya, Trivedi, Steve, Hopkins, Mohamed, Kazamel, Mohammad, Alsharabati, Liang, Lu, Kenkichi, Nozaki, Sandi, Mumfrey-Thomas, Amy, Woodall, Tahseen, Mozaffar, Tiyonnoh, Cash, Namita, Goyal, Gulmohor, Roy, Veena, Mathew, Fatima, Maqsood, Brian, Minton, H James Jones, Jeffrey, Rosenfeld, Rebekah, Garcia, Laura, Echevarria, Sonia, Garcia, Michael, Pulley, Shachie, Aranke, Alan Ross Berger, Jaimin, Shah, Yasmeen, Shabbir, Lisa, Smith, Mary, Varghese, Laurie, Gutmann, Ludwig, Gutmann, Nivedita, Jerath, Christopher, Nance, Andrea, Swenson, Heena, Olalde, Nicole, Kressin, Jeri, Sieren, Richard, Barohn, Mazen, Dimachkie, Melanie, Glenn, April, Mcvey, Mamatha, Pasnoor, Jeffery, Statland, Yunxia, Wang, Tina, Liu, Kelley, Emmons, Nicole, Jenci, Jerry, Locheke, Alex, Fondaw, Kathryn, Johns, Gabrielle, Rico, Maureen, Walsh, Laura, Herbelin, Charlene, Hafer-Macko, Justin, Kwan, Lindsay, Zilliox, Karen, Callison, Valerie, Young, Beth, Disanzo, Kerry, Naunton, Michael, Benatar, Martin, Bilsker, Khema, Sharma, Anne, Cooley, Eliana, Reyes, Sara-Claude, Michon, Danielle, Sheldon, Julie, Steele, Rebecca, Traub, Manisha, Chopra, Tuan, Vu, Lara, Katzin, Terry, Mcclain, Brittany, Harvey, Adam, Hart, Kristin, Huynh, Said, Beydoun, Amaiak, Chilingaryan, Victor, Doan, Brian, Droker, Hui, Gong, Sanaz, Karimi, Frank, Lin, Krishna, Polaka, Akshay, Shah, Anh, Tran, Salma, Akhter, Ali, Malekniazi, Rup, Tandan, Michael, Hehir, Waqar, Waheed, Shannon, Lucy, Michael, Weiss, Jane, Distad, Susan, Strom, Sharon, Downing, Bryan, Kim, Tulio, Bertorini, Thomas, Arnold, Kendrick, Henderson, Rekha, Pillai, Liu, Ye, Lauren, Wheeler, Jasmine, Hewlett, Mollie, Vanderhook, Richard, Nowak, Daniel, Dicapua, Benison, Keung, Aditya, Kumar, Huned, Patwa, Kimberly, Robeson, Irene, Yang, Joan, Nye, and Hong, Vu

Subjects
Adult, Male, 0301 basic medicine, medicine.medical_specialty, Clinical Neurology, Antibodies, Monoclonal, Humanized, Placebo, Article, Antibodies, Post-intervention, law.invention, 03 medical and health sciences, 0302 clinical medicine, Randomized controlled trial, Refractory, law, Internal medicine, Monoclonal, Myasthenia Gravis, Medicine and Health Sciences, Humans, Medicine, Humanized, Science & Technology, business.industry, Middle Aged, Eculizumab, Complement Inactivating Agents, Female, Treatment Outcome, EFFICACY, medicine.disease, Myasthenia gravis, Clinical trial, 030104 developmental biology, SAFETY, Neurosciences & Neurology, Neurology (clinical), business, Life Sciences & Biomedicine, COMPLEMENT INHIBITOR ECULIZUMAB, 030217 neurology & neurosurgery, medicine.drug
Abstract

ObjectiveTo evaluate whether eculizumab helps patients with anti–acetylcholine receptor–positive (AChR+) refractory generalized myasthenia gravis (gMG) achieve the Myasthenia Gravis Foundation of America (MGFA) post-intervention status of minimal manifestations (MM), we assessed patients' status throughout REGAIN (Safety and Efficacy of Eculizumab in AChR+ Refractory Generalized Myasthenia Gravis) and its open-label extension.MethodsPatients who completed the REGAIN randomized controlled trial and continued into the open-label extension were included in this tertiary endpoint analysis. Patients were assessed for the MGFA post-intervention status of improved, unchanged, worse, MM, and pharmacologic remission at defined time points during REGAIN and through week 130 of the open-label study.ResultsA total of 117 patients completed REGAIN and continued into the open-label study (eculizumab/eculizumab: 56; placebo/eculizumab: 61). At week 26 of REGAIN, more eculizumab-treated patients than placebo-treated patients achieved a status of improved (60.7% vs 41.7%) or MM (25.0% vs 13.3%; common OR: 2.3; 95% CI: 1.1–4.5). After 130 weeks of eculizumab treatment, 88.0% of patients achieved improved status and 57.3% of patients achieved MM status. The safety profile of eculizumab was consistent with its known profile and no new safety signals were detected.ConclusionEculizumab led to rapid and sustained achievement of MM in patients with AChR+ refractory gMG. These findings support the use of eculizumab in this previously difficult-to-treat patient population.ClinicalTrials.gov IdentifierREGAIN, NCT01997229; REGAIN open-label extension, NCT02301624.Classification of EvidenceThis study provides Class II evidence that, after 26 weeks of eculizumab treatment, 25.0% of adults with AChR+ refractory gMG achieved MM, compared with 13.3% who received placebo.

Published
2020
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5. Abstract 120: Vascular Endothelial Barrier Protection Prevents Atrial Fibrillation By Preserving Cardiac Nanostructure

Author

Louisa Mezache, Andrew Soltisz, Scott R Johnstone, Brant Isakson, and Rengasayee Veeraraghavan

Subjects
Cardiology and Cardiovascular Medicine
Abstract

Atrial fibrillation (AF) patients experience inflammation and vascular dysfunction and have elevated levels of cytokines that promote vascular leak and edema, such as vascular endothelial growth factor (VEGF). We previously identified edema-induced disruption of sodium channel (Na V 1.5) -rich intercalated disk (ID) nanodomains as a novel arrhythmia mechanism. Therefore, we hypothesized that: (i) VEGF-induced vascular leak acutely slows action potential propagation in the atria and increases arrhythmia risk by disrupting ID nanodomains, and (ii) protection of the vascular barrier can prevent vascular leak-induced atrial arrhythmias. Electron microscopy revealed ID nanodomain swelling, near both gap junctions (GJ) and mechanical junctions (MJ) following VEGF treatment (60 minutes) in mouse hearts. Super-resolution STORM and STED microscopy both revealed Na V 1.5 enrichment at GJ and MJ relative to other ID sites in control hearts. VEGF reduced Na V 1.5 enrichment at both sites, consistent with Na V 1.5 translocation from ID nanodomains. VEGF increased distance from GJs to 90% of Na V 1.5 signal (3.17μm vs. 0.47 μm in vehicle controls), measured by a distance transformation-based analysis of 3D confocal images of IDs. VEGF slowed atrial conduction (optical mapping) and increased atrial arrhythmia incidence (ECG) relative to vehicle controls in both ex vivo (80 vs 0%) and in vivo (70 vs 20%) studies. Overall, in vivo arrhythmia burden was higher in VEGF-treated mice (7.5±11 vs. 0±6s/hr in vehicle controls). Preserving the vascular barrier by blocking endothelial Panx1 channels (PxIL2P peptide) decreased VEGF-induced in vivo arrhythmia burden (0 ± 6.09 s/hr with 1.6 μM PxIL2P). Concurrently, distance from GJs to 90% of Na V 1.5 was restored to control levels (0.57μm) in these hearts. In summary, these results highlight inflammation-induced vascular leak as a novel AF mechanism, and suggest vascular barrier protection as an anti-arrhythmic strategy.

Published
2022
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9. Abstract 12129: Vascular Endothelial Barrier Protection May Prevent Arrhythmias in Atrial Fibrillation and Myocardial Infarction

Author

Louisa Mezache, Gerard Nuovo, and Rengasayee Veeraraghavan

Subjects
Physiology (medical), Cardiology and Cardiovascular Medicine
Abstract

Vascular leak is a major sequela of inflammation, which is associated with arrhythmic pathologies such as atrial fibrillation (AF) and myocardial infarction (MI). We recently demonstrated that the vascular leak-inducing cytokine vascular endothelial growth factor (VEGF; 90-580 pg/ml - levels found in AF patients) induces acute remodeling (30-60 minutes) of sodium channel (Na V 1.5) -rich intercalated disk (ID) nanodomains, disrupting their ultrastructure and prompting translocation of Na V 1.5 from these sites. This in turn disrupted impulse propagation and promoted arrhythmias in murine atria. Here, we tested the hypotheses that i) similar acute pro-arrhythmic remodeling occurs in the ventricles of MI patients, and ii) protecting the vascular barrier may prevent arrhythmias following an acute inflammatory insult. First, we examined myocardial samples from five human MI patients. VEGF was overexpressed in both cardiomyocytes and vascular endothelium in the border zone surrounding V 1.5 near both connexin43 and N-cadherin within the border zone in 1-, 3-, and 9-day-old infarcts, paralleling our observations in mouse atria. Next, we returned to our murine model of AF induced by acute inflammatory insult (100 pg/ml VEGF for 60 minutes) to test the antiarrhythmic efficacy of protecting the vascular endothelial barrier. Overall, median in vivo arrhythmia burden was higher in VEGF-treated mice relative to vehicle controls (7.5±11 vs. 0±6 s/hr). We tested two strategies shown to prevent vascular barrier breakdown: Blocking connexin43 hemichannels (αCT11 peptide) decreased in vivo arrhythmia burden to 0 ± 6.07 s/hr. Panx1-IL2 (a peptide inhibitor of Panx1 channels) treatment decreased also in vivo arrhythmia burden (0 ± 15.57 s/hr with 1.6 μM Panx1-IL2). Similar antiarrhythmic efficacy was also achieved with small molecule inhibitors of Cx43 and Panx1. These results highlight VEGF-induced vascular leak as a novel mechanism for acute arrhythmias both in the early stage AF and following MI. Indeed, this mechanism may contribute to post-MI AF. Importantly, vascular-barrier protection may be a viable strategy to prevent these arrhythmias.

Published
2021
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10. Super-Resolution Imaging Using a Novel High-Fidelity Antibody Reveals Close Association of the Neuronal Sodium Channel NaV1.6 with Ryanodine Receptors in Cardiac Muscle

Author

Justin Thomas, Louisa Mezache, Stephen Baine, Rengasayee Veeraraghavan, Przemysław B. Radwański, Kirk Mykytyn, Heather Struckman, and Sandor Gyorke

Subjects
0303 health sciences, biology, Ryanodine receptor, Chemistry, Sodium channel, Cardiac muscle, Proximity ligation assay, 030204 cardiovascular system & hematology, Ryanodine receptor 2, Cell biology, 03 medical and health sciences, 0302 clinical medicine, medicine.anatomical_structure, Affinity chromatography, Polyclonal antibodies, biology.protein, medicine, Myocyte, Instrumentation, 030304 developmental biology
Abstract

The voltage-gated sodium channel [pore-forming subunit of the neuronal voltage-gated sodium channel (NaV1.6)] has recently been found in cardiac myocytes. Emerging studies indicate a role for NaV1.6 in ionic homeostasis as well as arrhythmogenesis. Little is known about the spatial organization of these channels in cardiac muscle, mainly due to the lack of high-fidelity antibodies. Therefore, we developed and rigorously validated a novel rabbit polyclonal NaV1.6 antibody and undertook super-resolution microscopy studies of NaV1.6 localization in cardiac muscle. We developed and validated a novel rabbit polyclonal antibody against a C-terminal epitope on the neuronal sodium channel 1.6 (NaV1.6). Raw sera showed high affinity in immuno-fluorescence studies, which was improved with affinity purification. The antibody was rigorously validated for specificity via multiple approaches. Lastly, we used this antibody in proximity ligation assay (PLA) and super-resolution STochastic Optical Reconstruction Microscopy (STORM) studies, which revealed enrichment of NaV1.6 in close proximity to ryanodine receptor (RyR2), a key calcium (Ca2+) cycling protein, in cardiac myocytes. In summary, our novel NaV1.6 antibody demonstrates high degrees of specificity and fidelity in multiple preparations. It enabled multimodal microscopic studies and revealed that over half of the NaV1.6 channels in cardiac myocytes are located within 100 nm of ryanodine receptor Ca2+ release channels.

Published
2020
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11. Abstract P333: The Vascular Barrier: A Common Anti-arrhythmic Target In Atrial Fibrillation And Myocardial Infarction

Author

Louisa Mezache, Rengasayee Veeraraghavan, and Gerard J. Nuovo

Subjects
medicine.medical_specialty, Physiology, business.industry, Internal medicine, Cardiology, Medicine, Anti arrhythmic, Atrial fibrillation, Myocardial infarction, Cardiology and Cardiovascular Medicine, business, medicine.disease
Abstract

Vascular leak is a major sequela of inflammation, which is associated with arrhythmic pathologies such as atrial fibrillation (AF) and myocardial infarction (MI). We recently demonstrated that the vascular leak-inducing cytokine vascular endothelial growth factor (VEGF; 90-580 pg/ml - levels found in AF patients) induces acute remodeling (30-60 minutes) of sodium channel (Na V 1.5) -rich intercalated disk (ID) nanodomains, disrupting their ultrastructure and prompting translocation of Na V 1.5 from these sites. This in turn disrupted impulse propagation and promoted arrhythmias in murine atria. Here, we tested the hypotheses that i) similar acute pro-arrhythmic remodeling occurs in the ventricles of MI patients, and ii) protecting the vascular barrier may prevent arrhythmias following an acute inflammatory insult. First, we examined myocardial samples from five human MI patients. VEGF was overexpressed in both cardiomyocytes and vascular endothelium in the border zone surrounding V 1.5 near both connexin43 and N-cadherin within the border zone in 1-, 3-, and 9-day-old infarcts, paralleling our observations in mouse atria. Next, we returned to our murine model of AF induced by acute inflammatory insult (100 pg/ml VEGF for 60 minutes) to test the antiarrhythmic efficacy of protecting the vascular endothelial barrier. Overall, median in vivo arrhythmia burden was higher in VEGF-treated mice relative to vehicle controls (7.5±11 vs. 0±6 s/hr). We tested two strategies shown to prevent vascular barrier breakdown: Blocking connexin43 hemichannels (αCT11 peptide) decreased in vivo arrhythmia burden to 0 ± 6.07 s/hr. Panx1-IL2 (a peptide inhibitor of Panx1 channels) treatment decreased also in vivo arrhythmia burden (0 ± 15.57 s/hr with 1.6 μM Panx1-IL2). Similar antiarrhythmic efficacy was also achieved with small molecule inhibitors of Cx43 and Panx1. These results highlight VEGF-induced vascular leak as a novel mechanism for acute arrhythmias both in the early stage AF and following MI. Indeed, this mechanism may contribute to post-MI AF. Importantly, vascular-barrier protection may be a viable strategy to prevent these arrhythmias.

Published
2021
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12. Abstract 13383: The Vascular Endothelial Barrier: A Novel Therapeutic Target for Preventing Atrial Fibrillation

Author

Heather Struckman, Thomas J. Hund, Sandor Gyorke, Rengasayee Veeraraghavan, Anna Phillips, Przemysław B. Radwański, Amara Greer-Short, Louisa Mezache, and Stephen Baine

Subjects
medicine.medical_specialty, Endothelial barrier, business.industry, Physiology (medical), Internal medicine, Cardiology, Medicine, Atrial fibrillation, Cardiology and Cardiovascular Medicine, business, medicine.disease
Abstract

Atrial fibrillation (AF), the most common arrhythmia, is associated with inflammation and vascular dysfunction. AF patients have elevated levels of vascular endothelial growth factor (VEGF; 90-580 pg/ml), which promotes vascular leak and edema. We have previously identified edema-induced disruption of sodium channel (Na V 1.5) -rich intercalated disk (ID) nanodomains as a novel arrhythmia mechanism. We hypothesized that (i) elevated VEGF levels promote AF by disrupting ID nanodomains, and slowing atrial conduction, and (ii) protection of the vascular barrier can prevent these arrhythmias. Clinically-relevant VEGF levels (500 pg/ml, 60 minutes) increased FITC-dextran extravasation (99.3% vs. 24.3% in vehicle controls) in WT mouse hearts, consistent with increased vascular leak. Electron microscopy revealed ID nanodomain swelling, near both gap junctions (perinexi; 64±9nm vs 17±1nm) and mechanical junctions (63±4nm vs 27±2nm) in VEGF-treated hearts relative to controls. Super-resolution STORM microscopy revealed Na V 1.5 enrichment at perinexi (9±2 fold) and N-cadherin-rich sites (7±1 fold) relative to non-junctional ID sites in control hearts. VEGF reduced Na V 1.5 enrichment at both sites (6±1 and 4±1 fold, respectively), consistent with Na V 1.5 translocation from ID nanodomains. Atrial conduction, assessed by optical mapping, was slowed by VEGF (10±0.4 cm/s vs 21.3±1.3 cm/s at baseline). VEGF increased atrial arrhythmia burden both ex vivo (80% vs 0% in vehicle controls) and in vivo (70% vs 20% in vehicle controls). Next, we tested two strategies shown to prevent vascular barrier breakdown. Blocking connexin43 hemichannels (αCT11 peptide) decreased both incidence (40%) and duration (1.45±3.42s) of VEGF-induced arrhythmias. Likewise, blocking pannexin1 channels (Panx1-IL2 peptide) shortened VEGF-induced arrhythmias (2.48±0.83s). Mefloquine and spironolactone, which are small molecules that respectively inhibit Cx43 hemichannels and pannexin channels, were also found to effectively prevent VEGF-induced atrial arrhythmias. These results highlight VEGF-induced vascular leak as a novel mechanism for AF, and suggest vascular barrier protection as an anti-arrhythmic strategy.

Published
2020
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13. microRNA 155 up regulation in the CNS is strongly correlated to Down's syndrome dementia

Author

Gerard J. Nuovo, Vicky Amann, Adel Mikhail, James A. Williams, Louisa Mezache, Paolo Fadda, Paige Vandiver, Maria Quinonez, Esmerina Tili, and Jean-Jacques Michaille

Subjects
0301 basic medicine, Pathology, medicine.medical_specialty, DYRK1A, Cyclin D, Tau protein, In situ hybridization, Pathology and Forensic Medicine, Mice, 03 medical and health sciences, Alzheimer Disease, microRNA, medicine, Animals, Humans, Dementia, Dominance (genetics), biology, Brain, General Medicine, medicine.disease, Immunohistochemistry, Up-Regulation, Disease Models, Animal, MicroRNAs, 030104 developmental biology, Proto-Oncogene Proteins c-bcl-2, biology.protein, Down Syndrome, Chromosome 21
Abstract

This study examined the molecular correlates of Down's dementia. qRTPCR for chromosome 21 microRNAs was correlated with in situ hybridization, immunohistochemistry for microRNA targets, mRNAs located on chromosome 21, and neurofibrillary tangles in human and the Ts65 dn mouse Down's model. qRTPCR for the microRNAs on the triplicated chromosome showed miR-155 dominance in brain tissues (14.3 fold increase, human and 24.2 fold increase, mouse model) that co-expressed with hyperphosphorylated tau protein. miR-155 was not elevated in Alzheimer's disease or neonates with Downs' syndrome. Chromosome 21 genes APP/BA-42, DYRK1a and BACH1 were not correlated to pathologic changes in Down's dementia. Validated CNS targets of miR-155 that were present in controls and Alzheimer's disease but lacking in Down's dementia brains included BACH1, CoREST1, bcl6, BIM, bcl10, cyclin D, and SAPK4. It is concluded that Down's dementia strongly correlated with overexpression of chromosome 21 microRNA 155 with concomitant reduction of multiple CNS-functional targets. This study highlights the need for anatomic pathologists to determine the specific and diverse pathways cells may take to form neurofibrillary tangles in the different dementias.

Published
2018
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16. Designer Extracellular Vesicles Modulate Pro‐Neuronal Cell Responses and Improve Intracranial Retention (Adv. Healthcare Mater. 5/2022)

Author

Lilibeth Ortega‐Pineda, Alec Sunyecz, Ana I. Salazar‐Puerta, Maria Angelica Rincon‐Benavides, Diego Alzate‐Correa, Amrita Lakshmi Anaparthi, Elizabeth Guilfoyle, Louisa Mezache, Heather L. Struckman, Silvia Duarte‐Sanmiguel, Binbin Deng, David W. McComb, Daniel J. Dodd, William R. Lawrence, Jordan Moore, Jingjing Zhang, Eduardo Reátegui, Rengasayee Veeraraghavan, M. Tyler Nelson, Daniel Gallego‐Perez, and Natalia Higuita‐Castro

Subjects
Biomaterials, Biomedical Engineering, Pharmaceutical Science
Published
2022
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18. Diagnostic pathology of Alzheimer's disease from routine microscopy to immunohistochemistry and experimental correlations

Author

Gerard J. Nuovo, Vicky Amann, Bernard Paniccia, Paolo Fadda, James A. Williams, Louisa Mezache, Paige Vandiver, and Maria Quinonez

Subjects
0301 basic medicine, Pathology, medicine.medical_specialty, Programmed cell death, Amyloid, Tau protein, Cell, Hyperphosphorylation, tau Proteins, Pathology and Forensic Medicine, 03 medical and health sciences, 0302 clinical medicine, Alzheimer Disease, medicine, Humans, MCL1, Phosphorylation, Neurons, Microscopy, biology, Brain, General Medicine, Immunohistochemistry, 030104 developmental biology, medicine.anatomical_structure, 030220 oncology & carcinogenesis, biology.protein, Antibody
Abstract

The absence of any histologic correlate for Alzheimer's disease despite its commonness and severe clinical sequelae may offers clues to its etiology. Recent evidence strongly suggests that the central event of this disease is the hyperphosphorylation of neuronal tau protein and not the beta amyloid precipitates. In each case, essential and soluble neuronal proteins derivatives form insoluble aggregates that can readily be detected by immunohistochemistry using antibodies specific for the misfolded proteins. Immunohistochemistry also demonstrates that neurons with hyperphosphorylated tau protein are viable. Experimental evidence using neuronal cell cultures suggests that the affected neurons in Alzheimer's disease may have undergone molecular changes that include accumulation of anti-apopotic proteins MCL1 and cFLIP that do not allow the cell to undergo programmed cell death but, rather, to "immortalize" and thus accumulate hyperphosphorylated tau protein in the neuronal cell body and beta amyloid in downstream dendrites. We describe a simplified protocol to demonstrate such changes based on tagged LNA modified microRNA/antimicroRNA oligomers and cell cultures. Co-expression showed that the tagged antimiR-512 strongly localized with the markedly up-regulated proteins MCL1 and cFLIP with concomitant accumulation of hyperphosphorylated tau protein. The data underscore to the anatomic pathologist that the diagnosis of Alzheimer's disease is best accomplished by simple immunohistochemistry tests correlated to the clinical history and the key role pathologists can play in understanding the cause of the disease.

Published
2017
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20. Super-Resolution Imaging Using a Novel High-Fidelity Antibody Reveals Close Association of the Neuronal Sodium Channel Na

Author

Heather L, Struckman, Stephen, Baine, Justin, Thomas, Louisa, Mezache, Kirk, Mykytyn, Sándor, Györke, Przemysław B, Radwański, and Rengasayee, Veeraraghavan

Subjects
Mice, Inbred C57BL, Mice, Knockout, Microscopy, Fluorescence, NAV1.6 Voltage-Gated Sodium Channel, Myocardium, Optical Imaging, Animals, Ryanodine Receptor Calcium Release Channel, Article
Abstract

The voltage-gated sodium channel [pore-forming subunit of the neuronal voltage-gated sodium channel (NaV1.6)] has recently been found in cardiac myocytes. Emerging studies indicate a role for NaV1.6 in ionic homeostasis as well as arrhythmogenesis. Little is known about the spatial organization of these channels in cardiac muscle, mainly due to the lack of high-fidelity antibodies. Therefore, we developed and rigorously validated a novel rabbit polyclonal NaV1.6 antibody and undertook super-resolution microscopy studies of NaV1.6 localization in cardiac muscle. We developed and validated a novel rabbit polyclonal antibody against a C-terminal epitope on the neuronal sodium channel 1.6 (NaV1.6). Raw sera showed high affinity in immuno-fluorescence studies, which was improved with affinity purification. The antibody was rigorously validated for specificity via multiple approaches. Lastly, we used this antibody in proximity ligation assay (PLA) and super-resolution STochastic Optical Reconstruction Microscopy (STORM) studies, which revealed enrichment of NaV1.6 in close proximity to ryanodine receptor (RyR2), a key calcium (Ca2+) cycling protein, in cardiac myocytes. In summary, our novel NaV1.6 antibody demonstrates high degrees of specificity and fidelity in multiple preparations. It enabled multimodal microscopic studies and revealed that over half of the NaV1.6 channels in cardiac myocytes are located within 100 nm of ryanodine receptor Ca2+ release channels.

Published
2020

21. Long-term efficacy and safety of eculizumab in Japanese patients with generalized myasthenia gravis: A subgroup analysis of the REGAIN open-label extension study

Author

Hiroyuki Murai, Akiyuki Uzawa, Yasushi Suzuki, Tomihiro Imai, Hirokazu Shiraishi, Hidekazu Suzuki, Meinoshin Okumura, Fanny O’Brien, Jing-Jing Wang, Kenji P. Fujita, Kimiaki Utsugisawa, Claudio Gabriel Mazia, Miguel Wilken, Fabio Barroso, Juliet Saba, Marcelo Rugiero, Mariela Bettini, Marcelo Chaves, Gonzalo Vidal, Alejandra Dalila Garcia, Jan De Bleecker, Guy Van den Abeele, Kathy de Koning, Katrien De Mey, Rudy Mercelis, Délphine Mahieu, Linda Wagemaekers, Philip Van Damme, Annelies Depreitere, Caroline Schotte, Charlotte Smetcoren, Olivier Stevens, Sien Van Daele, Nicolas Vandenbussche, Annelies Vanhee, Sarah Verjans, Jan Vynckier, Ann D'Hondt, Petra Tilkin, Alzira Alves de Siqueira Carvalho, Igor Dias Brockhausen, David Feder, Daniel Ambrosio, Pamela César, Ana Paula Melo, Renata Martins Ribeiro, Rosana Rocha, Bruno Bezerra Rosa, Thabata Veiga, Luiz Augusto da Silva, Murilo Santos Engel, Jordana Gonçalves Geraldo, Maria da Penha Ananias Morita, Erica Nogueira Coelho, Gabriel Paiva, Marina Pozo, Natalia Prando, Debora Dada Martineli Torres, Cristiani Fernanda Butinhao, Gustavo Duran, Tamires Cristina Gomes da Silva, Luiz Otavio Maia Gonçalves, Lucas Eduardo Pazetto, Tomás Augusto Suriane Fialho, Luciana Renata Cubas Volpe, Luciana Souza Duca, Acary Souza Bulle Oliveira, Ana Carolina Amaral Andrade, Marcelo Annes, Liene Duarte Silva, Valeria Cavalcante Lino, Wladimir Pinto, Natália Assis, Fernanda Carrara, Carolina Miranda, Iandra Souza, Patricia Fernandes, Zaeem Siddiqi, Cecile Phan, Jeffrey Narayan, Derrick Blackmore, Ashley Mallon, Rikki Roderus, Elizabeth Watt, Jana Junkerova, Barbora Kurkova, Katarina Reguliova, Olga Zapletalova, Jiri Pitha, Iveta Novakova, Michaela Tyblova, Ivana Jurajdova, Marcela Wolfova, Henning Andersen, Thomas Harbo, Lotte Vinge, Susanne Krogh, Anita Mogensen, John Vissing, Joan Højgaard, Nanna Witting, Anne Mette Ostergaard Autzen, Jane Pedersen, Juha-Pekka Eralinna, Mikko Laaksonen, Olli Oksaranta, Tuula Harrison, Jaana Eriksson, Csilla Rozsa, Melinda Horvath, Gabor Lovas, Judit Matolcsi, Gyorgyi Szabo, Gedeonne Jakab, Brigitta Szabadosne, Giovanni Antonini, Antonella Di Pasquale, Matteo Garibaldi, Stefania Morino, Fernanda Troili, Laura Fionda, Allessandro Filla, Teresa Costabile, Enrico Marano, Francesco Saccà, Angiola Fasanaro, Angela Marsili, Giorgia Puorro, Renato Mantegazza, Carlo Antozzi, Silvia Bonanno, Giorgia Camera, Alberta Locatelli, Lorenzo Maggi, Maria Pasanisi, Angela Campanella, Amelia Evoli, Paolo Emilio Alboini, Valentina D'Amato, Raffaele Iorio, Tetsuya Kanai, Naoki Kawaguchi, Masahiro Mori, Yoko Kaneko, Akiko Kanzaki, Eri Kobayashi, Katsuhisa Masaki, Dai Matsuse, Takuya Matsushita, Taira Uehara, Misa Shimpo, Maki Jingu, Keiko Kikutake, Yumiko Nakamura, Yoshiko Sano, Yuriko Nagane, Ikuko Kamegamori, Tomoko Tsuda, Yuko Fujii, Kazumi Futono, Yukiko Ozawa, Aya Mizugami, Yuka Saito, Miyuki Morikawa, Makoto Samukawa, Sachiko Kamakura, Eriko Miyawaki, Teiichiro Mitazaki, Masakatsu Motomura, Akihiro Mukaino, Shunsuke Yoshimura, Shizuka Asada, Seiko Yoshida, Shoko Amamoto, Tomomi Kobashikawa, Megumi Koga, Yasuko Maeda, Kazumi Takada, Mihoko Takada, Masako Tsurumaru, Yumi Yamashita, Tetsuya Akiyama, Koichi Narikawa, Ohito Tano, Kenichi Tsukita, Rikako Kurihara, Fumie Meguro, Yusuke Fukuda, Miwako Sato, Soichiro Funaka, Tomohiro Kawamura, Masayuki Makamori, Masanori Takahashi, Namie Taichi, Tomoya Hasuike, Eriko Higuchi, Hisako Kobayashi, Kaori Osakada, Emiko Tsuda, Shun Shimohama, Takashi Hayashi, Shin Hisahara, Jun Kawamata, Takashi Murahara, Masaki Saitoh, Shuichiro Suzuki, Daisuke Yamamoto, Yoko Ishiyama, Naoko Ishiyama, Mayuko Noshiro, Rumi Takeyama, Kaori Uwasa, Ikuko Yasuda, Anneke van der Kooi, Marianne de Visser, Tamar Gibson, Carlos Casasnovas, Maria Antonia Alberti Aguilo, Christian Homedes-Pedret, Natalia Julia Palacios, Laura Diez Porras, Valentina Velez Santamaria, Ana Lazaro, Exuperio Diez Tejedor, Pilar Gomez Salcedo, Mireya Fernandez-Fournier, Pedro Lopez Ruiz, Francisco Javier Rodriguez de Rivera, Maria Sastre, Josep Gamez, Pilar Sune, Maria Salvado, Gisela Gili, Gonzalo Mazuela, Isabel Illa, Elena Cortes Vicente, Jordi Diaz-Manera, Luis Antonio Querol Gutierrez, Ricardo Rojas Garcia, Nuria Vidal, Elisabet Arribas-Ibar, Fredrik Piehl, Albert Hietala, Lena Bjarbo, Ihsan Sengun, Arzu Meherremova, Pinar Ozcelik, Bengu Balkan, Celal Tuga, Muzeyyen Ugur, Sevim Erdem-Ozdamar, Can Ebru Bekircan-Kurt, Nazire Pinar Acar, Ezgi Yilmaz, Yagmur Caliskan, Gulsah Orsel, Husnu Efendi, Seda Aydinlik, Hakan Cavus, Ayse Kutlu, Gulsah Becerikli, Cansu Semiz, Ozlem Tun, Murat Terzi, Baki Dogan, Musa Kazim Onar, Sedat Sen, Tugce Kirbas Cavdar, Adife Veske, Fiona Norwood, Aikaterini Dimitriou, Jakit Gollogly, Mohamed Mahdi-Rogers, Arshira Seddigh, Giannis Sokratous, Gal Maier, Faisal Sohail, Saiju Jacob, Girija Sadalage, Pravin Torane, Claire Brown, Amna Shah, Sivakumar Sathasivam, Heike Arndt, Debbie Davies, Dave Watling, Anthony Amato, Thomas Cochrane, Mohammed Salajegheh, Kristen Roe, Katherine Amato, Shirli Toska, Gil Wolfe, Nicholas Silvestri, Kara Patrick, Karen Zakalik, Jonathan Katz, Robert Miller, Marguerite Engel, Dallas Forshew, Elena Bravver, Benjamin Brooks, Sarah Plevka, Maryanne Burdette, Scott Cunningham, Mohammad Sanjak, Megan Kramer, Joanne Nemeth, Clara Schommer, Scott Tierney, Vern Juel, Jeffrey Guptill, Lisa Hobson-Webb, Janice Massey, Kate Beck, Donna Carnes, John Loor, Amanda Anderson, Robert Pascuzzi, Cynthia Bodkin, John Kincaid, Riley Snook, Sandra Guingrich, Angela Micheels, Vinay Chaudhry, Andrea Corse, Betsy Mosmiller, Andrea Kelley, Doreen Ho, Jayashri Srinivasan, Michal Vytopil, Jordan Jara, Nicholas Ventura, Stephanie Scala, Cynthia Carter, Craig Donahue, Carol Herbert, Elaine Weiner, Sharmeen Alam, Jonathan McKinnon, Laura Haar, Naya McKinnon, Karan Alcon, Kaitlyn McKenna, Nadia Sattar, Kevin Daniels, Dennis Jeffery, Miriam Freimer, Joseph Chad Hoyle, John Kissel, Julie Agriesti, Sharon Chelnick, Louisa Mezache, Colleen Pineda, Filiz Muharrem, Chafic Karam, Julie Khoury, Tessa Marburger, Harpreet Kaur, Diana Dimitrova, James Gilchrist, Brajesh Agrawal, Mona Elsayed, Stephanie Kohlrus, Angela Andoin, Taylor Darnell, Laura Golden, Barbara Lokaitis, Jenna Seelback, Srikanth Muppidi, Neelam Goyal, Sarada Sakamuri, Yuen T. So, Shirley Paulose, Sabrina Pol, Lesly Welsh, Ratna Bhavaraju-Sanka, Alejandro Tobon Gonzales, Lorraine Dishman, Floyd Jones, Anna Gonzalez, Patricia Padilla, Amy Saklad, Marcela Silva, Mohamed Kazamel, Mohammad Alsharabati, Liang Lu, Kenkichi Nozaki, Sandi Mumfrey-Thomas, Amy Woodall, Tahseen Mozaffar, Tiyonnoh Cash, Namita Goyal, Gulmohor Roy, Veena Mathew, Fatima Maqsood, Brian Minton, H. James Jones, Jeffrey Rosenfeld, Rebekah Garcia, Laura Echevarria, Sonia Garcia, Michael Pulley, Shachie Aranke, Alan Ross Berger, Jaimin Shah, Yasmeen Shabbir, Lisa Smith, Mary Varghese, Laurie Gutmann, Ludwig Gutmann, Nivedita Jerath, Christopher Nance, Andrea Swenson, Heena Olalde, Nicole Kressin, Jeri Sieren, Richard Barohn, Mazen Dimachkie, Melanie Glenn, April McVey, Mamatha Pasnoor, Jeffery Statland, Yunxia Wang, Tina Liu, Kelley Emmons, Nicole Jenci, Jerry Locheke, Alex Fondaw, Kathryn Johns, Gabrielle Rico, Maureen Walsh, Laura Herbelin, Charlene Hafer-Macko, Justin Kwan, Lindsay Zilliox, Karen Callison, Valerie Young, Beth DiSanzo, Kerry Naunton, Michael Benatar, Martin Bilsker, Khema Sharma, Anne Cooley, Eliana Reyes, Sara-Claude Michon, Danielle Sheldon, Julie Steele, James Howard Jr, Manisha Chopra, Rebecca Traub, Tuan Vu, Lara Katzin, Terry McClain, Brittany Harvey, Adam Hart, Kristin Huynh, Said Beydoun, Amaiak Chilingaryan, Victor Doan, Brian Droker, Hui Gong, Sanaz Karimi, Frank Lin, Krishna Pokala, Akshay Shah, Anh Tran, Salma Akhter, Ali Malekniazi, Rup Tandan, Michael Hehir, Waqar Waheed, Shannon Lucy, Michael Weiss, Jane Distad, Susan Strom, Sharon Downing, Bryan Kim, Richard Nowak, Daniel Dicapua, Benison Keung, Aditya Kumar, Huned Patwa, Kimberly Robeson, Irene Yang, Joan Nye, Hong Vu, H., Murai, A., Uzawa, Y., Suzuki, T., Imai, H., Shiraishi, H., Suzuki, M., Okumura, F., O'Brien, J. -J., Wang, K. P., Fujita, K., Utsugisawa, Gabriel Mazia 11, Claudio, Wilken 11, Miguel, Barroso 11, Fabio, Saba 11, Juliet, Rugiero 12, Marcelo, Bettini 12, Mariela, Chaves 12, Marcelo, Vidal 12, Gonzalo, Dalila Garcia 12, Alejandra, De Bleecker 13, Jan, Van den Abeele 13, Guy, de Koning 13, Kathy, De Mey 13, Katrien, Mercelis 14, Rudy, Mahieu 14, Délphine, Wagemaekers 14, Linda, Van Damme 15, Philip, Depreitere 16, Annelie, Schotte 16, Caroline, Smetcoren 16, Charlotte, Stevens 16, Olivier, Van Daele 16, Sien, Vandenbussche 16, Nicola, Vanhee 16, Annelie, Verjans 16, Sarah, Vynckier 16, Jan, D'Hondt 16, Ann, Tilkin 16, Petra, Alves de Siqueira Carvalho 17, Alzira, Dias Brockhausen 17, Igor, Feder 17, David, Ambrosio 17, Daniel, César 17, Pamela, Paula Melo 17, Ana, Martins Ribeiro 17, Renata, Rocha 17, Rosana, Bezerra Rosa 17, Bruno, Veiga 17, Thabata, Augusto da Silva 17, Luiz, Santos Engel 17, Murilo, Gonçalves Geraldo 17, Jordana, da Penha Ananias Morita 18, Maria, Nogueira Coelho 18, Erica, Paiva 18, Gabriel, Pozo 18, Marina, Prando 18, Natalia, Dada Martineli Torres 18, Debora, Fernanda Butinhao 18, Cristiani, Duran 18, Gustavo, Cristina Gomes da Silva 18, Tamire, Otavio Maia Gonçalves 18, Luiz, Eduardo Pazetto 18, Luca, Augusto Suriane Fialho 18, Tomá, Renata Cubas Volpe 18, Luciana, Souza Duca 18, Luciana, Souza Bulle Oliveira 19, Acary, Carolina Amaral Andrade 19, Ana, Annes 19, Marcelo, Duarte Silva 19, Liene, Cavalcante Lino 19, Valeria, Pinto 19, Wladimir, Assis 19, Natália, Carrara 19, Fernanda, Miranda 19, Carolina, Souza 19, Iandra, Fernandes 19, Patricia, Siddiqi 20, Zaeem, Phan 20, Cecile, Narayan 20, Jeffrey, Blackmore 20, Derrick, Mallon 20, Ashley, Roderus 20, Rikki, Watt 20, Elizabeth, Junkerova 21, Jana, Kurkova 21, Barbora, Reguliova 21, Katarina, Zapletalova 21, Olga, Pitha 22, Jiri, Novakova 22, Iveta, Tyblova 22, Michaela, Jurajdova 22, Ivana, Wolfova 22, Marcela, Andersen 23, Henning, Harbo 23, Thoma, Vinge 23, Lotte, Krogh 23, Susanne, Mogensen 23, Anita, Vissing 24, John, Højgaard 24, Joan, Witting 24, Nanna, Mette Ostergaard Autzen 24, Anne, Pedersen 24, Jane, Eralinna 25, Juha-Pekka, Laaksonen 25, Mikko, Oksaranta 25, Olli, Harrison 25, Tuula, Eriksson 25, Jaana, Rozsa 26, Csilla, Horvath 26, Melinda, Lovas 26, Gabor, Matolcsi 26, Judit, Szabo 26, Gyorgyi, Jakab 26, Gedeonne, Szabadosne 26, Brigitta, Antonini 27, Giovanni, Di Pasquale 27, Antonella, Garibaldi 27, Matteo, Morino 27, Stefania, Troili 27, Fernanda, Fionda 27, Laura, Filla, Allessandro, Costabile, Teresa, Marano, Enrico, Sacca', Francesco, Fasanaro, Angiola, Marsili, Angela, Puorro, Giorgia, Mantegazza 29, Renato, Antozzi 29, Carlo, Bonanno 29, Silvia, Camera 29, Giorgia, Locatelli 29, Alberta, Maggi 29, Lorenzo, Pasanisi 29, Maria, Campanella 29, Angela, Evoli 30, Amelia, Emilio Alboini 30, Paolo, D'Amato 30, Valentina, Iorio 30, Raffaele, Kanai 31, Tetsuya, Kawaguchi 31, Naoki, Mori 31, Masahiro, Kaneko 31, Yoko, Kanzaki 31, Akiko, Kobayashi 31, Eri, Masaki 32, Katsuhisa, Matsuse 32, Dai, Matsushita 32, Takuya, Uehara 32, Taira, Shimpo 32, Misa, Jingu 32, Maki, Kikutake 32, Keiko, Nakamura 32, Yumiko, Sano 32, Yoshiko, Nagane 33, Yuriko, Kamegamori 33, Ikuko, Tsuda 33, Tomoko, Fujii 33, Yuko, Futono 33, Kazumi, Ozawa 33, Yukiko, Mizugami 33, Aya, Saito 33, Yuka, Morikawa 34, Miyuki, Samukawa 34, Makoto, Kamakura 34, Sachiko, Miyawaki 34, Eriko, Mitazaki 35, Teiichiro, Motomura 35, Masakatsu, Mukaino 35, Akihiro, Yoshimura 35, Shunsuke, Asada 35, Shizuka, Yoshida 35, Seiko, Amamoto 35, Shoko, Kobashikawa 35, Tomomi, Koga 35, Megumi, Maeda 35, Yasuko, Takada 35, Kazumi, Takada 35, Mihoko, Tsurumaru 35, Masako, Yamashita 35, Yumi, Akiyama 36, Tetsuya, Narikawa 36, Koichi, Tano 36, Ohito, Tsukita 36, Kenichi, Kurihara 36, Rikako, Meguro 36, Fumie, Fukuda 36, Yusuke, Sato 36, Miwako, Funaka 37, Soichiro, Kawamura 37, Tomohiro, Makamori 37, Masayuki, Takahashi 37, Masanori, Taichi 37, Namie, Hasuike 37, Tomoya, Higuchi 37, Eriko, Kobayashi 37, Hisako, Osakada 37, Kaori, Tsuda 38, Emiko, Shimohama 38, Shun, Hayashi 38, Takashi, Hisahara 38, Shin, Kawamata 38, Jun, Murahara 38, Takashi, Saitoh 38, Masaki, Suzuki 38, Shuichiro, Yamamoto 38, Daisuke, Ishiyama 38, Yoko, Ishiyama 38, Naoko, Noshiro 38, Mayuko, Takeyama 38, Rumi, Uwasa 38, Kaori, Yasuda 38, Ikuko, van der Kooi 39, Anneke, de Visser 39, Marianne, Gibson 39, Tamar, Casasnovas 40, Carlo, Antonia Alberti Aguilo 40, Maria, Homedes-Pedret 40, Christian, Julia Palacios 40, Natalia, Diez Porras 40, Laura, Velez Santamaria 40, Valentina, Lazaro 40, Ana, Diez Tejedor 41, Exuperio, Gomez Salcedo 41, Pilar, Fernandez-Fournier 41, Mireya, Lopez Ruiz 41, Pedro, Javier Rodriguez de Rivera 41, Francisco, Sastre 41, Maria, Gamez 42, Josep, Sune 42, Pilar, Salvado 42, Maria, Gili 42, Gisela, Mazuela 42, Gonzalo, Illa 43, Isabel, Cortes Vicente 43, Elena, Diaz-Manera 43, Jordi, Antonio Querol Gutierrez 43, Lui, Rojas Garcia 43, Ricardo, Vidal 43, Nuria, Arribas-Ibar 43, Elisabet, Piehl 44, Fredrik, Hietala 44, Albert, Bjarbo 44, Lena, Sengun 45, Ihsan, Meherremova 45, Arzu, Ozcelik 45, Pinar, Balkan 45, Bengu, Tuga 45, Celal, Ugur 45, Muzeyyen, Erdem-Ozdamar 46, Sevim, Ebru Bekircan-Kurt 46, Can, Pinar Acar 46, Nazire, Yilmaz 46, Ezgi, Caliskan 46, Yagmur, Orsel 46, Gulsah, Efendi 47, Husnu, Aydinlik 47, Seda, Cavus 47, Hakan, Kutlu 47, Ayse, Becerikli 47, Gulsah, Semiz 47, Cansu, Tun 47, Ozlem, Terzi 48, Murat, Dogan 48, Baki, Kazim Onar 48, Musa, Sen 48, Sedat, Kirbas Cavdar 48, Tugce, Veske 48, Adife, Norwood 49, Fiona, Dimitriou 49, Aikaterini, Gollogly 49, Jakit, Mahdi-Rogers 49, Mohamed, Seddigh 49, Arshira, Sokratous 49, Gianni, Maier 49, Gal, Sohail 49, Faisal, Jacob 50, Saiju, Sadalage 50, Girija, Torane 50, Pravin, Brown 50, Claire, Shah 50, Amna, Sathasivam 51, Sivakumar, Arndt 51, Heike, Davies 51, Debbie, Watling 51, Dave, Amato 52, Anthony, Cochrane 52, Thoma, Salajegheh 52, Mohammed, Roe 52, Kristen, Amato 52, Katherine, Toska 52, Shirli, Wolfe 53, Gil, Silvestri 53, Nichola, Patrick 53, Kara, Zakalik 53, Karen, Katz 54, Jonathan, Miller 54, Robert, Engel 54, Marguerite, Forshew 54, Dalla, Bravver 55, Elena, Brooks 55, Benjamin, Plevka 55, Sarah, Burdette 55, Maryanne, Cunningham 55, Scott, Sanjak 55, Mohammad, Kramer 55, Megan, Nemeth 55, Joanne, Schommer 55, Clara, Tierney 55, Scott, Juel 56, Vern, Guptill 56, Jeffrey, Hobson-Webb 56, Lisa, Massey 56, Janice, Beck 56, Kate, Carnes 56, Donna, Loor 56, John, Anderson 56, Amanda, Pascuzzi 57, Robert, Bodkin 57, Cynthia, Kincaid 57, John, Snook 57, Riley, Guingrich 57, Sandra, Micheels 57, Angela, Chaudhry 58, Vinay, Corse 58, Andrea, Mosmiller 58, Betsy, Kelley 58, Andrea, Ho 59, Doreen, Srinivasan 59, Jayashri, Vytopil 59, Michal, Jara 59, Jordan, Ventura 59, Nichola, Scala 59, Stephanie, Carter 59, Cynthia, Donahue 59, Craig, Herbert 59, Carol, Weiner 59, Elaine, Alam 59, Sharmeen, McKinnon 60, Jonathan, Haar 60, Laura, McKinnon 60, Naya, Alcon 60, Karan, McKenna 60, Kaitlyn, Sattar 60, Nadia, Daniels 60, Kevin, Jeffery 60, Denni, Freimer 61, Miriam, Chad Hoyle 61, Joseph, Kissel 61, John, Agriesti 61, Julie, Chelnick 61, Sharon, Mezache 61, Louisa, Pineda 61, Colleen, Muharrem 61, Filiz, Karam 62, Chafic, Khoury 62, Julie, Marburger 62, Tessa, Kaur 62, Harpreet, Dimitrova 62, Diana, Gilchrist 63, Jame, Agrawal 63, Brajesh, Elsayed 63, Mona, Kohlrus 63, Stephanie, Andoin 63, Angela, Darnell 63, Taylor, Golden 63, Laura, Lokaitis 63, Barbara, Seelback 63, Jenna, Muppidi 64, Srikanth, Goyal 64, Neelam, Sakamuri 64, Sarada, T So 64, Yuen, Paulose 64, Shirley, Pol 64, Sabrina, Welsh 64, Lesly, Bhavaraju-Sanka 65, Ratna, Tobon Gonzales 65, Alejandro, Dishman 65, Lorraine, Jones 65, Floyd, Gonzalez 65, Anna, Padilla 65, Patricia, Saklad 65, Amy, Silva 65, Marcela, Kazamel 66, Mohamed, Alsharabati 66, Mohammad, Lu 66, Liang, Nozaki 66, Kenkichi, Mumfrey-Thomas 66, Sandi, Woodall 66, Amy, Mozaffar 67, Tahseen, Cash 67, Tiyonnoh, Goyal 67, Namita, Roy 67, Gulmohor, Mathew 67, Veena, Maqsood 67, Fatima, Minton 67, Brian, James Jones 68, H, Rosenfeld 68, Jeffrey, Garcia 68, Rebekah, Echevarria 68, Laura, Garcia 68, Sonia, Pulley 69, Michael, Aranke 69, Shachie, Ross Berger 69, Alan, Shah 69, Jaimin, Shabbir 69, Yasmeen, Smith 69, Lisa, Varghese 69, Mary, Gutmann 70, Laurie, Gutmann 70, Ludwig, Jerath 70, Nivedita, Nance 70, Christopher, Swenson 70, Andrea, Olalde 70, Heena, Kressin 70, Nicole, Sieren 70, Jeri, Barohn 71, Richard, Dimachkie 71, Mazen, Glenn 71, Melanie, McVey 71, April, Pasnoor 71, Mamatha, Statland 71, Jeffery, Wang 71, Yunxia, Liu 71, Tina, Emmons 71, Kelley, Jenci 71, Nicole, Locheke 71, Jerry, Fondaw 71, Alex, Johns 71, Kathryn, Rico 71, Gabrielle, Walsh 71, Maureen, Herbelin 71, Laura, Hafer-Macko 72, Charlene, Kwan 72, Justin, Zilliox 72, Lindsay, Callison 72, Karen, Young 72, Valerie, DiSanzo 72, Beth, Naunton 72, Kerry, Benatar 73, Michael, Bilsker 73, Martin, Sharma 73, Khema, Cooley 73, Anne, Reyes 73, Eliana, Michon 73, Sara-Claude, Sheldon 73, Danielle, Steele 73, Julie, Howard Jr 74, Jame, Karam 74, Chafic, Chopra 74, Manisha, Traub 74, Rebecca, Vu 75, Tuan, Katzin 75, Lara, McClain 75, Terry, Harvey 75, Brittany, Hart 75, Adam, Huynh 75, Kristin, Beydoun 76, Said, Chilingaryan 76, Amaiak, Doan 76, Victor, Droker 76, Brian, Gong 76, Hui, Karimi 76, Sanaz, Lin 76, Frank, McClain 76, Terry, Pokala 76, Krishna, Shah 76, Akshay, Tran 76, Anh, Akhter 76, Salma, Malekniazi 76, Ali, Tandan 77, Rup, Hehir 77, Michael, Waheed 77, Waqar, Lucy 77, Shannon, Weiss 78, Michael, Distad 78, Jane, Strom 78, Susan, Downing 78, Sharon, Kim 78, Bryan, Nowak 79, Richard, Dicapua 79, Daniel, Keung 79, Benison, Kumar 79, Aditya, Patwa 79, Huned, Robeson 79, Kimberly, Yang 79, Irene, Nye 79, Joan, and Hong Vu

Subjects
Male, Pediatrics, Myasthenia gravi, Open-label extension study, Complement inhibitor, 0302 clinical medicine, Quality of life, Japan, Medicine and Health Sciences, Medicine, 030212 general & internal medicine, Myasthenia gravis, education.field_of_study, MG-ADL, Japanese patient, Eculizumab, Middle Aged, HLA, MG-QoL15, Treatment Outcome, Neurology, Female, Life Sciences & Biomedicine, COMPLEMENT INHIBITOR ECULIZUMAB, medicine.drug, Adult, medicine.medical_specialty, Population, Clinical Neurology, Subgroup analysis, Placebo, Antibodies, Monoclonal, Humanized, 03 medical and health sciences, Refractory, Asian People, Myasthenia Gravis, Humans, education, Aged, Science & Technology, business.industry, Neurosciences, medicine.disease, Complement Inactivating Agents, Japanese patients, ONSET, Neurology (clinical), Neurosciences & Neurology, business, 030217 neurology & neurosurgery
Abstract

The terminal complement inhibitor eculizumab was shown to improve myasthenia gravis-related symptoms in the 26-week, phase 3, randomized, double-blind, placebo-controlled REGAIN study (NCT01997229). In this 52-week sub-analysis of the open-label extension of REGAIN (NCT02301624), eculizumab's efficacy and safety were assessed in 11 Japanese and 88 Caucasian patients with anti-acetylcholine receptor antibody-positive refractory generalized myasthenia gravis. For patients who had received placebo during REGAIN, treatment with open-label eculizumab resulted in generally similar outcomes in the Japanese and Caucasian populations. Rapid improvements were maintained for 52 weeks, assessed by change in score from open-label extension baseline to week 52 (mean [standard error]) using the following scales (in Japanese and Caucasian patients, respectively): Myasthenia Gravis Activities of Daily Living (-2.4 [1.34] and - 3.3 [0.65]); Quantitative Myasthenia Gravis (-2.9 [1.98] and - 4.3 [0.79]); Myasthenia Gravis Composite (-4.5 [2.63] and - 4.9 [1.19]); and Myasthenia Gravis Quality of Life 15-item questionnaire (-8.6 [5.68] and - 6.5 [1.93]). Overall, the safety of eculizumab was consistent with its known safety profile. In this interim sub-analysis, the efficacy and safety of eculizumab in Japanese and Caucasian patients were generally similar, and consistent with the overall REGAIN population. ispartof: JOURNAL OF THE NEUROLOGICAL SCIENCES vol:407 ispartof: location:Netherlands status: published

Published
2019

23. The Nanoscale Basis of Atrial Fibrillation: Functional Impact of Disrupting NaV1.5-rich Intercalated Disk Nanodomains

Author

Stephen Baine, Rengasayee Veeraraghavan, Anna Phillips, Louisa Mezache, Thomas J. Hund, Amara Greer-Short, Heather Struckman, and Sandor Gyorke

Subjects
Materials science, biology, Intercalated disk, medicine, biology.protein, Biophysics, Functional impact, Atrial fibrillation, Nav1.5, medicine.disease, Instrumentation, Nanoscopic scale
Abstract

Background:Atrial fibrillation (AF), which is characterized by chaotic patterns of electrical activation of the atria, affects over 4 million people in the US alone. We previously identified nanoscale structural abnormalities in the hearts of AF patients. Specifically, they displayed swelling of gap junction (GJ) –adjacent perinexi, specialized nanodomains rich in cardiac sodium channels (NaV1.5) and located within intercalated disks (IDs; sites of electromechanical contact between adjacent cells). However, the functional consequences of these nanoscale structural changes remain unclear.Objective:We assessed the structural and functional impacts of selectively disrupting different NaV1.5-rich ID nanodomains.Methods and Results:We utilized peptide mimetics of adhesion domains to selectively inhibit adhesion within different ID nanodomains: 1) Nadp1 (target: N-cadherin), 2) dadp1 (target: Desmoglein-2), and 3) βadp1 (target: sodium channel β1 subunit [SCN1b]). Each active peptide was compared against a corresponding inactive control peptide (Nadp1-c, dadp1-c, βadp1-scr). Sub-diffraction confocal imaging revealed ID enrichment of active peptides, but not inactive controls. Furthermore, each active peptide was preferentially localized in ID regions rich in its corresponding protein target. Peptide treatment (100 μM; 60 minutes) of ex vivo mouse hearts revealed profound widening of perinexi by βadp1 and of mechanical junctions by Nadp1. Dadp1 also induced widening of mechanical junctions albeit to a lower degree. STORM single molecule localization microscopy identified about 50&per; of ID-localized NaV1.5 within GJ-adjacent perinexi, while an additional ∼35&per; was located within N-cad-rich ID sites. Nadp1 and βadp1 induced redistribution of ID localized NaV1.5 away from perinexi and mechanical junctions respectively. Dadp1, again, had similar but milder effects compared to Nadp1. Western blot revealed the expression levels of NaV1.5, connexin 43 (Cx43), connexin 40 (Cx40), β1 in peptide treated hearts to be within 10&per; of levels in untreated controls. Optical mapping revealed atrial conduction slowing in hearts treated with Nadp1 (17cm/s, 70.83&per; of control) and βadp1 (13 cm/s, 54.17&per; of control), but not inactive control peptides (24 cm/s). Volume-conducted electrocardiograms (ECG) revealed P wave prolongation in active peptide treated hearts (Nadp1: 26.5ms, βadp1: 31ms), consistent with conduction slowing compared to the inactive control peptides (16ms). Importantly, burst pacing elicited atrial arrhythmias in all hearts treated with Nadp1 and βadp1. Arrhythmia burden (duration, number of arrhythmias) was highest with βadp1.Conclusions:These results suggest that disruption of NaV1.5-rich ID nanodomains impairs electrical impulse propagation and promotes arrhythmias in the atria. Furthermore, the magnitude of functional impacts are likely determined by the amount of sodium channels contained within the nanodomains disrupted.

Published
2020
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24. Enhancement of Cardiac Store Operated Calcium Entry (SOCE) within Novel Intercalated Disk Microdomains in Arrhythmic Disease

Author

G. A. Sakuta, Rengasayee Veeraraghavan, Stephen Baine, Sandor Gyorke, Cynthia A. Carnes, Tom Bodnar, Andriy E. Belevych, Silvia G. Priori, Ingrid M. Bonilla, Noah Weisleder, Bin Liu, Louisa Mezache, Andrei V. Stepanov, Przemysław B. Radwański, and Pompeo Volpe

Subjects
0301 basic medicine, Male, ORAI1 Protein, Calcium and vitamin D, lcsh:Medicine, Article, 03 medical and health sciences, Mice, 0302 clinical medicine, Downregulation and upregulation, Myocyte, Animals, Myocytes, Cardiac, Calcium Signaling, Gene Knock-In Techniques, Stromal Interaction Molecule 1, lcsh:Science, Excitation Contraction Coupling, Catecholaminergic, Multidisciplinary, Chemistry, Myocardium, lcsh:R, Calcium signalling, Wild type, Arrhythmias, Cardiac, Store-operated calcium entry, Cell biology, Coupling (electronics), Mice, Inbred C57BL, Sarcoplasmic Reticulum, 030104 developmental biology, cardiovascular system, Cholinergic, lcsh:Q, Calcium, Female, Calcium Channels, 030217 neurology & neurosurgery, Intracellular
Abstract

Store-operated Ca2+ entry (SOCE), a major Ca2+ signaling mechanism in non-myocyte cells, has recently emerged as a component of Ca2+ signaling in cardiac myocytes. Though it has been reported to play a role in cardiac arrhythmias and to be upregulated in cardiac disease, little is known about the fundamental properties of cardiac SOCE, its structural underpinnings or effector targets. An even greater question is how SOCE interacts with canonical excitation-contraction coupling (ECC). We undertook a multiscale structural and functional investigation of SOCE in cardiac myocytes from healthy mice (wild type; WT) and from a genetic murine model of arrhythmic disease (catecholaminergic ventricular tachycardia; CPVT). Here we provide the first demonstration of local, transient Ca2+entry (LoCE) events, which comprise cardiac SOCE. Although infrequent in WT myocytes, LoCEs occurred with greater frequency and amplitude in CPVT myocytes. CPVT myocytes also evidenced characteristic arrhythmogenic spontaneous Ca2+ waves under cholinergic stress, which were effectively prevented by SOCE inhibition. In a surprising finding, we report that both LoCEs and their underlying protein machinery are concentrated at the intercalated disk (ID). Therefore, localization of cardiac SOCE in the ID compartment has important implications for SOCE-mediated signaling, arrhythmogenesis and intercellular mechanical and electrical coupling in health and disease.

Published
2019

26. Enhanced expression of PD L1 in cervical intraepithelial neoplasia and cervical cancers

Author

Louisa Mezache, Bernard Paniccia, Gerard J. Nuovo, and Angelique Nyinawabera

Subjects
Pathology, medicine.medical_specialty, Uterine Cervical Neoplasms, Adenocarcinoma, Biology, Cervical intraepithelial neoplasia, B7-H1 Antigen, Pathology and Forensic Medicine, Biomarkers, Tumor, medicine, Humans, Cervix, In Situ Hybridization, Cervical cancer, Papillomavirus Infections, HPV infection, Cancer, Uterine Cervical Dysplasia, medicine.disease, Immunohistochemistry, Koilocyte, Up-Regulation, medicine.anatomical_structure, Cytopathology, Carcinoma, Squamous Cell, Female
Abstract

Programmed death ligand 1 (PD L1) expression can reduce the immune response in both infectious diseases and cancers. We thus examined PD L1 expression in cervical intraepithelial neoplasias (CINs) and cancers since they each reflect infection by human papillomavirus (HPV). PD L1 protein was not evident by immunohistochemistry in histologically normal cervical epithelia (0/55) even when adjacent to CIN or cancer. PD L1 expression was much increased in CINs (20/21=95%) and cervical squamous cell cancer (56/70=80%) and localized to the dysplastic/neoplastic squamous cells and mononuclear cells, respectively. There was also a significant increase (each P

Published
2015
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27. Increased expression of importin-β, exportin-5 and nuclear transportable proteins in Alzheimer's disease aids anatomic pathologists in its diagnosis

Author

Louisa Mezache, Vicky Amann, Bernard Paniccia, James A. Williams, Gerard J. Nuovo, Paige Vandiver, Maria Quinonez, Adel Mikhail, and Paolo Fadda

Subjects
0301 basic medicine, Pathology, medicine.medical_specialty, Tau protein, Disease, Karyopherins, Pathology and Forensic Medicine, Surgical pathology, 03 medical and health sciences, 0302 clinical medicine, Alzheimer Disease, medicine, Dementia, Humans, Messenger RNA, biology, Brain, General Medicine, medicine.disease, beta Karyopherins, Pathologists, 030104 developmental biology, Real-time polymerase chain reaction, Proto-Oncogene Proteins c-bcl-2, Apoptosis, biology.protein, Immunohistochemistry, 030217 neurology & neurosurgery, Biomarkers
Abstract

Understanding the metabolic profile of neurons with the hyperphosphorylated tau protein characteristic of Alzheimer's disease is essential to unraveling new potential therapies and diagnostics for the surgical pathologist. We stratified 75 brain tissues from Alzheimer's disease into hyperphosphorylated tau positive or negative and did co-expression analyses and qRTPCR for importin-β and exportin-5 plus several bcl2 family members and compared the data to controls, Down's dementia and Parkinson's disease. There was a significant increase in the expression of importin-β and exportin-5 in Alzheimer's disease relative to the three other categories (each p value

Published
2017

31. Modulation of PD-L1 and CD8 Activity in Idiopathic and Infectious Chronic Inflammatory Conditions

Author

Flavia Pichiorri, Gerard J. Nuovo, Douglas W. Sborov, Craig C. Hofmeister, Cynthia M. Magro, and Louisa Mezache

Subjects
0301 basic medicine, Male, Histology, Inflammation, CD8-Positive T-Lymphocytes, Infections, Peripheral blood mononuclear cell, T-Lymphocytes, Regulatory, B7-H1 Antigen, Article, Pathology and Forensic Medicine, 03 medical and health sciences, Mice, 0302 clinical medicine, Immune system, Cell Line, Tumor, medicine, Cytotoxic T cell, Animals, Humans, biology, business.industry, FOXP3, Mice, Inbred C57BL, Medical Laboratory Technology, Mononuclear cell infiltration, 030104 developmental biology, Granzyme, 030220 oncology & carcinogenesis, Immunology, Chronic Disease, biology.protein, Female, medicine.symptom, business, CD8
Abstract

Programmed death-ligand 1 (PD-L1) can reduce the immune response by inhibiting CD8 T-cell proliferation and cytotoxic activity. We studied a series of human viral (molloscum, human papillomavirus, herpes simplex, cytomegalovirus, Epstein-Barr virus, smallpox) and bacterial infections (Helicobacter pylori) for the in situ expression of PD-L1, mononuclear cell infiltration, and CD8 activity and compared this to noninfectious idiopathic inflammatory conditions to better define which immune responses may be more highly correlated with an infectious agent. Each viral and bacterial infection showed an increased PD-L1 expression that was most prominent in the mononuclear cell/CD8+ infiltrate surrounding the infection. However, the CD8 cells were mostly quiescent as evidenced by the low Ki67 index and minimal granzyme expression. Using a melanoma mouse model, acute reovirus infection increased PD-L1 expression, but decreased CD8 cytotoxic activity and Treg (FOXP3) cell numbers. In comparison, idiopathic noninfectious chronic inflammatory processes including lichen sclerosis, eczema, Sjogren's disease, and ulcerative colitis showed a comparable strong PD-L1 expression in the mononuclear cell infiltrates but much greater Treg infiltration. However, this strong immunosuppressor profile was ineffective as evidenced by strong CD8 proliferation and granzyme expression. These data suggest that viral and bacterial infections induce a PD-L1 response that, unlike noninfectious chronic inflammatory conditions, dampens the activity of the recruited CD8 cells which, in turn, may enhance the ability of anti-PD-L1 therapy to eliminate the infectious agent.

Published
2016

32. Reduced miR-512 and the Elevated Expression of Its Targets cFLIP and MCL1 Localize to Neurons With Hyperphosphorylated Tau Protein in Alzheimer Disease

Author

Gerard J. Nuovo, Madison Mikhail, Michela Garofalo, and Louisa Mezache

Subjects
Male, Pathology, medicine.medical_specialty, Histology, Tau protein, CASP8 and FADD-Like Apoptosis Regulating Protein, Caspase 3, Apoptosis, tau Proteins, Biology, Caspase 8, Pathology and Forensic Medicine, Alzheimer Disease, medicine, In Situ Nick-End Labeling, Humans, MCL1, APAF1, Phosphorylation, Aged, Regulation of gene expression, Aged, 80 and over, Neurons, TUNEL assay, Amyloid beta-Peptides, Apoptosis Inducing Factor, Brain, Minichromosome Maintenance Complex Component 2, medicine.disease, Immunohistochemistry, Caspases, Initiator, Cell biology, Medical Laboratory Technology, MicroRNAs, Apoptotic Protease-Activating Factor 1, Gene Expression Regulation, biology.protein, Myeloid Cell Leukemia Sequence 1 Protein, Female, Alzheimer's disease
Abstract

The cause for the neurofibrillary tangles and plaques in Alzheimer disease likely relates to an abnormal accumulation of their key components, which include β-amyloid and hyperphosphorylated tau protein. We segregated Alzheimer brain sections from people with end-stage disease into those with abundant hyperphosphorylated tau protein and those without and compared each to normal brains for global microRNA patterns. A significant reduced expression of several microRNAs, including miR-512, was evident in the Alzheimer brain sections with abundant hyperphosphorylated tau. Immunohistochemistry documented that 2 known targets of microRNA-512, cFLIP and MCL1, were significantly over expressed and each colocalized to neurons with the abnormal tau protein. Analysis for apoptosis including activated caspase-3, increased caspase-4 and caspase-8, apoptosis initiating factor, APAF-1 activity, and the TUNEL assay was negative in the areas where neurons showed hyperphosphorylated tau. MCM2 expression, a marker of neuroprogenitor cells, was significantly reduced in the Alzheimer sections that contained the hyperphosphorylated tau. These results suggest that a basic defect in Alzheimer disease may be the reduced microRNA-driven increased expression of proteins that may alter the apoptotic/antiapoptotic balance of neurons. This, in turn, could lead to the accumulation of key Alzheimer proteins such as hyperphosphorylated tau that ultimately prevent normal neuronal function and lead to disease symptomatology.

Published
2015

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