{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"institution":[{"name":"bioRxiv"}],"indexed":{"date-parts":[[2026,1,31]],"date-time":"2026-01-31T00:52:34Z","timestamp":1769820754596,"version":"3.49.0"},"posted":{"date-parts":[[2023,7,3]]},"group-title":"Pharmacology and Toxicology","reference-count":26,"publisher":"openRxiv","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"accepted":{"date-parts":[[2023,7,5]]},"abstract":"<jats:title>Abstract<\/jats:title>\n                <jats:p>\n                  Ca\n                  <jats:sup>2+<\/jats:sup>\n                  leak from cardiac ryanodine receptor (RyR2) is an established mechanism of sudden cardiac death (SCD), whereby dysregulated Ca\n                  <jats:sup>2+<\/jats:sup>\n                  handling causes ventricular arrhythmias. We previously discovered the RyR2-selective inhibitor\n                  <jats:italic>ent-<\/jats:italic>\n                  (+)-verticilide (\n                  <jats:italic>ent<\/jats:italic>\n                  -1), a 24-membered cyclooligomeric depsipeptide that is the enantiomeric form of a natural product (\n                  <jats:italic>nat<\/jats:italic>\n                  -(-)-verticilide). Here, we examined its 18-membered ring-size oligomer (\n                  <jats:italic>ent<\/jats:italic>\n                  -verticilide B1; \u201c\n                  <jats:italic>ent<\/jats:italic>\n                  -B1\u201d) in single RyR2 channel assays, [\n                  <jats:sup>3<\/jats:sup>\n                  H]ryanodine binding assays, and in\n                  <jats:italic>Casq2<\/jats:italic>\n                  <jats:sup>-\/-<\/jats:sup>\n                  cardiomyocytes and mice, a gene-targeted model of SCD.\n                  <jats:italic>ent<\/jats:italic>\n                  -B1 inhibited RyR2 single-channels and [\n                  <jats:sup>3<\/jats:sup>\n                  H]ryanodine binding with low micromolar potency, and RyR2-mediated spontaneous Ca\n                  <jats:sup>2+<\/jats:sup>\n                  release in Casq2-\/- cardiomyocytes with sub-micromolar potency.\n                  <jats:italic>ent<\/jats:italic>\n                  -B1 was a partial RyR2 inhibitor, with maximal inhibitory efficacy of less than 50%.\n                  <jats:italic>ent<\/jats:italic>\n                  -B1 was stable in plasma, with a peak plasma concentration of 1460 ng\/ml at 10 min and half-life of 45 min after intraperitoneal administration of 3 mg\/kg in mice. Both 3 mg\/kg and 30 mg\/kg\n                  <jats:italic>ent<\/jats:italic>\n                  -B1 significantly reduced catecholamine-induced ventricular arrhythmia in Casq2-\/- mice. Hence, we have identified a novel chemical entity \u2013\n                  <jats:italic>ent<\/jats:italic>\n                  -B1 \u2013 that preserves the mechanism of action of a hit compound and shows therapeutic efficacy. These findings strengthen RyR2 as an antiarrhythmic drug target and highlight the potential of investigating the mirror-image isomers of natural products to discover new therapeutics.\n                <\/jats:p>\n                <jats:sec>\n                  <jats:title>Significance statement<\/jats:title>\n                  <jats:p>The cardiac ryanodine receptor (RyR2) is an untapped target in the stagnant field of antiarrhythmic drug development. We have confirmed RyR2 as an antiarrhythmic target in a mouse model of sudden cardiac death and shown the therapeutic efficacy of a second enantiomeric natural product.<\/jats:p>\n                <\/jats:sec>","DOI":"10.1101\/2023.07.03.547578","type":"posted-content","created":{"date-parts":[[2023,7,4]],"date-time":"2023-07-04T00:55:22Z","timestamp":1688432122000},"source":"Crossref","is-referenced-by-count":2,"title":["<i>ent<\/i>\n                  -Verticilide B1 inhibits type 2 ryanodine receptor channels and is antiarrhythmic in Casq2-\/- mice"],"prefix":"10.64898","author":[{"given":"Aaron","family":"Gochman","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tri Q.","family":"Do","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kyungsoo","family":"Kim","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jacob A.","family":"Schwarz","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Madelaine P.","family":"Thorpe","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Daniel J.","family":"Blackwell","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Abigail N.","family":"Smith","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Wendell S.","family":"Akers","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Razvan L.","family":"Cornea","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Derek R.","family":"Laver","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jeffrey N.","family":"Johnston","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4956-9735","authenticated-orcid":false,"given":"Bjorn C.","family":"Knollmann","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"54368","reference":[{"key":"2023071205265726000_2023.07.03.547578v2.1","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.1816685116"},{"key":"2023071205265726000_2023.07.03.547578v2.2","doi-asserted-by":"publisher","DOI":"10.1038\/415198a"},{"key":"2023071205265726000_2023.07.03.547578v2.3","doi-asserted-by":"crossref","unstructured":"Blackwell DJ , Faggioni M , Wleklinski MJ , Gomez-Hurtado N , Venkataraman R , Gibbs CE , Baudenbacher FJ , Gong S , Fishman GI , Boyle PM , Pfeifer K and Knollmann BC (2022) The Purkinje-myocardial junction is the anatomic origin of ventricular arrhythmia in CPVT. JCI Insight 7(3).","DOI":"10.1172\/jci.insight.151893"},{"key":"2023071205265726000_2023.07.03.547578v2.4","doi-asserted-by":"publisher","DOI":"10.1124\/jpet.122.001455"},{"key":"2023071205265726000_2023.07.03.547578v2.5","unstructured":"Brunton LL and Knollmann BC (2023) Goodman & Gilman\u2019s the pharmacological basis of therapeutics. Fourteenth edition. ed. McGraw Hill Medical, New York."},{"key":"2023071205265726000_2023.07.03.547578v2.6","doi-asserted-by":"publisher","DOI":"10.1056\/NEJM198908103210629"},{"issue":"1","key":"2023071205265726000_2023.07.03.547578v2.7","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1021\/acsmedchemlett.0c00581","article-title":"Steering New Drug Discovery Campaigns: Permeability, Solubility, and Physicochemical Properties in the bRo5 Chemical Space","volume":"12","year":"2021","journal-title":"ACS Med Chem Lett"},{"key":"2023071205265726000_2023.07.03.547578v2.8","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1016\/j.yjmcc.2023.04.005","article-title":"The selective RyR2 inhibitor ent-verticilide suppresses atrial fibrillation susceptibility caused by Pitx2 deficiency","volume":"180","year":"2023","journal-title":"Journal of molecular and cellular cardiology"},{"key":"2023071205265726000_2023.07.03.547578v2.9","doi-asserted-by":"publisher","DOI":"10.1038\/nature06799"},{"key":"2023071205265726000_2023.07.03.547578v2.10","doi-asserted-by":"publisher","DOI":"10.1056\/NEJMoa0800456"},{"issue":"3","key":"2023071205265726000_2023.07.03.547578v2.11","doi-asserted-by":"crossref","first-page":"321","DOI":"10.1161\/CIRCRESAHA.120.316819","article-title":"RYR2 Channel Inhibition Is the Principal Mechanism of Flecainide Action in CPVT","volume":"128","year":"2021","journal-title":"Circulation research"},{"key":"2023071205265726000_2023.07.03.547578v2.12","doi-asserted-by":"publisher","DOI":"10.1007\/BF00235394"},{"key":"2023071205265726000_2023.07.03.547578v2.13","doi-asserted-by":"publisher","DOI":"10.1161\/01.CIR.91.5.1512"},{"key":"2023071205265726000_2023.07.03.547578v2.14","doi-asserted-by":"publisher","DOI":"10.1016\/j.ddtec.2004.11.007"},{"key":"2023071205265726000_2023.07.03.547578v2.15","doi-asserted-by":"publisher","DOI":"10.1016\/S0092-8674(00)80847-8"},{"key":"2023071205265726000_2023.07.03.547578v2.16","doi-asserted-by":"publisher","DOI":"10.1016\/S0006-3495(03)74976-5"},{"issue":"5","key":"2023071205265726000_2023.07.03.547578v2.17","doi-asserted-by":"crossref","first-page":"255","DOI":"10.1038\/ja.2012.12","article-title":"New verticilides, inhibitors of acyl-CoA:cholesterol acyltransferase, produced by Verticillium sp. FKI-2679","volume":"65","year":"2012","journal-title":"J Antibiot (Tokyo)"},{"key":"2023071205265726000_2023.07.03.547578v2.18","doi-asserted-by":"publisher","DOI":"10.1161\/CIRCRESAHA.112.268094"},{"issue":"2","key":"2023071205265726000_2023.07.03.547578v2.19","doi-asserted-by":"crossref","first-page":"77","DOI":"10.1038\/ja.2009.126","article-title":"Verticilide, a new ryanodine-binding inhibitor, produced by Verticillium sp. FKI-1033","volume":"63","year":"2010","journal-title":"J Antibiot (Tokyo)"},{"issue":"12","key":"2023071205265726000_2023.07.03.547578v2.20","doi-asserted-by":"crossref","first-page":"1942","DOI":"10.1021\/acsmedchemlett.1c00508","article-title":"Ring Size as an Independent Variable in Cyclooligomeric Depsipeptide Antiarrhythmic Activity","volume":"12","year":"2021","journal-title":"ACS Med Chem Lett"},{"key":"2023071205265726000_2023.07.03.547578v2.21","doi-asserted-by":"publisher","DOI":"10.1161\/CIRCRESAHA.108.184457"},{"key":"2023071205265726000_2023.07.03.547578v2.22","doi-asserted-by":"publisher","DOI":"10.1021\/jm020017n"},{"issue":"9019","key":"2023071205265726000_2023.07.03.547578v2.23","first-page":"7","article-title":"Effect of d-sotalol on mortality in patients with left ventricular dysfunction after recent and remote myocardial infarction","volume":"348","year":"1996","journal-title":"The SWORD Investigators. Survival With Oral d-Sotalol. Lancet"},{"key":"2023071205265726000_2023.07.03.547578v2.24","doi-asserted-by":"publisher","DOI":"10.1038\/nm.1942"},{"key":"2023071205265726000_2023.07.03.547578v2.25","doi-asserted-by":"publisher","DOI":"10.1016\/j.jelectrocard.2011.07.025"},{"key":"2023071205265726000_2023.07.03.547578v2.26","doi-asserted-by":"publisher","DOI":"10.1161\/hc4301.098254"}],"container-title":[],"original-title":[],"link":[{"URL":"https:\/\/syndication.highwire.org\/content\/doi\/10.1101\/2023.07.03.547578","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2026,1,15]],"date-time":"2026-01-15T04:51:12Z","timestamp":1768452672000},"score":1,"resource":{"primary":{"URL":"http:\/\/biorxiv.org\/lookup\/doi\/10.1101\/2023.07.03.547578"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,7,3]]},"references-count":26,"URL":"https:\/\/doi.org\/10.1101\/2023.07.03.547578","relation":{},"subject":[],"published":{"date-parts":[[2023,7,3]]},"subtype":"preprint"}}