{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,28]],"date-time":"2026-02-28T08:45:49Z","timestamp":1772268349827,"version":"3.50.1"},"reference-count":17,"publisher":"PeerJ","license":[{"start":{"date-parts":[[2022,7,12]],"date-time":"2022-07-12T00:00:00Z","timestamp":1657584000000},"content-version":"unspecified","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Hainan Provincial Natural Science Foundation of China","award":["No. 820RC640"],"award-info":[{"award-number":["No. 820RC640"]}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["No. 82060365"],"award-info":[{"award-number":["No. 82060365"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/501100001809","name":"National Natural Science Foundation of China","doi-asserted-by":"crossref","award":["81660335"],"award-info":[{"award-number":["81660335"]}],"id":[{"id":"10.13039\/501100001809","id-type":"DOI","asserted-by":"crossref"}]},{"name":"Major Science and Technology Program of Hainan Province","award":["ZDKJ202003"],"award-info":[{"award-number":["ZDKJ202003"]}]},{"name":"Research project of Hainan academician innovation platform","award":["YSPTZX202004"],"award-info":[{"award-number":["YSPTZX202004"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":[],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Cyclocytidine hydrochloride (HCl) has been reported to inhibit DNA synthesis by affecting DNA polymerase. Here, we tested the antiviral effect of cyclocytidine on hepatitis B virus (HBV) DNA synthesis, which is reliant on DNA polymerase activity.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Materials and Methods<\/jats:title>\n                    <jats:p>Cyclocytidine HCl was treated to HBV-producing HepAD38 cells or added to an endogenous polymerase reaction, and HBV DNA was detected by Southern blot.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>Treatment of 20 \u00b5M cyclocytidine HCl significantly decreased the production of relaxed circular (rc) DNA in HepAD38 cells and block rcDNA synthesis in endogenous polymerase reaction (EPR), a cell free assay, possibly by inhibiting the HBV DNA polymerase activity.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusion<\/jats:title>\n                    <jats:p>Cyclocytidine HCl could inhibit the synthesis of HBV rcDNA, the precursor of covalently closed circular DNA, and this result provides a case for the usage of \u201cold\u201d drugs for \u201cnew\u201d applications.<\/jats:p>\n                  <\/jats:sec>","DOI":"10.7717\/peerj.13719","type":"journal-article","created":{"date-parts":[[2022,7,12]],"date-time":"2022-07-12T03:38:27Z","timestamp":1657597107000},"page":"e13719","source":"Crossref","is-referenced-by-count":6,"title":["Cyclocytidine hydrochloride inhibits the synthesis of relaxed circular DNA of hepatitis B virus"],"prefix":"10.7717","volume":"10","author":[{"given":"Xue","family":"Wang","sequence":"first","affiliation":[{"name":"School of Basic Medicine and Life Science, Hainan Medical University, Haikou, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yihan","family":"Xiao","sequence":"additional","affiliation":[{"name":"School of Basic Medicine and Life Science, Hainan Medical University, Haikou, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhigang","family":"Cui","sequence":"additional","affiliation":[{"name":"School of Basic Medicine and Life Science, Hainan Medical University, Haikou, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zongxin","family":"Li","sequence":"additional","affiliation":[{"name":"School of Basic Medicine and Life Science, Hainan Medical University, Haikou, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lihua","family":"Li","sequence":"additional","affiliation":[{"name":"School of Basic Medicine and Life Science, Hainan Medical University, Haikou, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Lixian","family":"Wu","sequence":"additional","affiliation":[{"name":"School of Basic Medicine and Life Science, Hainan Medical University, Haikou, 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