{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,6]],"date-time":"2026-10-06T18:52:59Z","timestamp":1791312779142,"version":"4.3.1"},"reference-count":38,"publisher":"American Physiological Society","issue":"4","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Journal of Applied Physiology"],"published-print":{"date-parts":[[2018,10,1]]},"abstract":"<jats:p>\n                    5-Methyltetrahydrofolate (5-MTHF) is important for nitric oxide (NO)-mediated cutaneous microvascular vasodilation. Ultraviolet B (UVB) radiation may deplete 5-MTHF, either directly or via production of reactive oxygen species (ROS), decreasing NO-mediated vasodilation. We hypothesized that 1) acute UVB exposure would attenuate NO-dependent cutaneous vasodilation, 2) local perfusion of 5-MTHF or ascorbate (ASC) (antioxidant) would augment NO-dependent vasodilation after UVB, and 3) darker skin pigmentation would be UVB-protective. Intradermal microdialysis fibers ( n = 3) placed in each forearm of 22 healthy young adults (23\u2009\u00b1\u20091 yr; 8M\/14F) locally delivered lactated Ringer\u2019s (control), 5 mM 5-MTHF, or 10 mM ASC. One arm was UVB-exposed (300 mJ\/cm\n                    <jats:sup>2<\/jats:sup>\n                    ), and the other served as a nonexposed control (CON). Following UVB exposure, a standardized local heating (42\u00b0C) protocol induced cutaneous vasodilation. After attaining a plateau blood flow, 15 mM N\n                    <jats:sup>G<\/jats:sup>\n                    -nitro-l-arginine methyl ester (nitric oxide synthase inhibiter) was infused at all sites to quantify the NO contribution. Red cell flux was measured at each site by laser-Doppler flowmetry (LDF), and cutaneous vascular conductance (CVC\u2009=\u2009LDF\/mean arterial pressure) was expressed as a percentage of maximum (28 mM sodium nitroprusside + 43\u00b0C). UVB attenuated NO-mediated vasodilation compared with CON (23.1\u2009\u00b1\u20093.6 vs. 33.9\u2009\u00b1\u20093.4%; P\u2009= 0.001). Delivery of 5-MTHF or ASC improved NO-mediated vasodilation versus lactated Ringer\u2019s in the UVB-exposed arm (MTHF: 30.1\u2009\u00b1\u20094.8% vs. 23.1\u2009\u00b1\u20093.8%; P = 0.03; ASC: 30.9\u2009\u00b1\u20094.3% vs. 23.1\u2009\u00b1\u20093.8%; P = 0.02). Neither treatment affected the response in the nonexposed arm ( P \u2265 0.09). Skin pigmentation (melanin index) was not predictive of the UVB response ( P \u2265 0.34). These data suggest that acute UVB exposure attenuates NO-mediated vasodilation via direct and\/or ROS-induced reductions in 5-MTHF, independent of skin pigmentation.\n                  <\/jats:p>\n                  <jats:p>NEW &amp; NOTEWORTHY Endothelial-derived nitric oxide (NO) contributes to normal healthy function of the human cutaneous microvasculature. Bioavailability of 5-methyltetrahydrofolate (5-MTHF) is important for the production of NO. Ultraviolet (UV) radiation exposure, specifically UVB, may deplete cutaneous 5-MTHF, thereby reducing NO-mediated microvascular function. Our findings suggest that acute UVB exposure attenuates NO-mediated vasodilation of the cutaneous microvasculature via degradation of 5-MTHF. These findings advance our understanding of the potential negative health impacts of acute UV exposure.<\/jats:p>","DOI":"10.1152\/japplphysiol.00501.2018","type":"journal-article","created":{"date-parts":[[2018,8,23]],"date-time":"2018-08-23T15:56:57Z","timestamp":1535039817000},"page":"1232-1237","source":"Crossref","is-referenced-by-count":19,"title":["Acute ultraviolet radiation exposure attenuates nitric oxide-mediated vasodilation in the cutaneous microvasculature of healthy humans"],"prefix":"10.1152","volume":"125","author":[{"given":"S. Tony","family":"Wolf","sequence":"first","affiliation":[{"name":"Department of Kinesiology, The Pennsylvania State University, University Park, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anna E.","family":"Stanhewicz","sequence":"additional","affiliation":[{"name":"Department of Kinesiology, The Pennsylvania State University, University Park, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nina G.","family":"Jablonski","sequence":"additional","affiliation":[{"name":"Anthropology, The Pennsylvania State University, University Park, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"W. Larry","family":"Kenney","sequence":"additional","affiliation":[{"name":"Department of Kinesiology, The Pennsylvania State University, University Park, Pennsylvania"},{"name":"Graduate Program in Physiology, The Pennsylvania State University, University Park, Pennsylvania"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"24","reference":[{"key":"B1","doi-asserted-by":"publisher","DOI":"10.1152\/ajpregu.00448.2012"},{"key":"B2","doi-asserted-by":"publisher","DOI":"10.1111\/1523-1747.ep12479191"},{"key":"B3","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.01354.2011"},{"key":"B4","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2012.236398"},{"key":"B5","doi-asserted-by":"publisher","DOI":"10.1016\/j.abb.2006.12.017"},{"key":"B6","doi-asserted-by":"publisher","DOI":"10.1016\/j.niox.2011.04.004"},{"key":"B7","doi-asserted-by":"publisher","DOI":"10.1002\/lsm.20239"},{"key":"B8","doi-asserted-by":"publisher","DOI":"10.1159\/000051543"},{"key":"B9","doi-asserted-by":"publisher","DOI":"10.1126\/science.6256855"},{"key":"B10","doi-asserted-by":"publisher","DOI":"10.1113\/jphysiol.2011.212100"},{"key":"B11","doi-asserted-by":"publisher","DOI":"10.1113\/EP086776"},{"key":"B12","doi-asserted-by":"publisher","DOI":"10.1146\/annurev.anthro.33.070203.143955"},{"key":"B13","doi-asserted-by":"publisher","DOI":"10.1006\/jhev.2000.0403"},{"key":"B14","doi-asserted-by":"publisher","DOI":"10.1073\/pnas.0914628107"},{"key":"B15","doi-asserted-by":"publisher","DOI":"10.1111\/j.1475-097X.1986.tb00239.x"},{"key":"B16","doi-asserted-by":"publisher","DOI":"10.2340\/00015555-2269"},{"key":"B17","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1998.85.3.824"},{"key":"B18","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.1999.86.4.1185"},{"key":"B19","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00589.2017"},{"key":"B20","doi-asserted-by":"publisher","DOI":"10.1016\/j.mvr.2018.02.001"},{"key":"B21","doi-asserted-by":"publisher","DOI":"10.1002\/ajhb.22929"},{"key":"B22","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00414.2010"},{"key":"B23","doi-asserted-by":"publisher","DOI":"10.1152\/jappl.2001.91.4.1619"},{"key":"B24","doi-asserted-by":"publisher","DOI":"10.1152\/japplphysiol.00229.2002"},{"key":"B25","doi-asserted-by":"publisher","DOI":"10.1096\/fj.11-195859"},{"key":"B26","doi-asserted-by":"publisher","DOI":"10.1097\/00005768-200108000-00021"},{"key":"B27","doi-asserted-by":"publisher","DOI":"10.1159\/000018428"},{"key":"B28","doi-asserted-by":"publisher","DOI":"10.1016\/j.jphotobiol.2005.03.001"},{"key":"B29","doi-asserted-by":"publisher","DOI":"10.1053\/sper.2002.34773"},{"key":"B30","doi-asserted-by":"publisher","DOI":"10.1038\/ng1440"},{"key":"B31","doi-asserted-by":"publisher","DOI":"10.1039\/C3PP50348H"},{"key":"B32","doi-asserted-by":"publisher","DOI":"10.1161\/HYPERTENSIONAHA.111.178129"},{"key":"B33","doi-asserted-by":"publisher","DOI":"10.1017\/S0007114516002579"},{"key":"B34","doi-asserted-by":"publisher","DOI":"10.1042\/CS20140821"},{"key":"B35","doi-asserted-by":"publisher","DOI":"10.1152\/ajpregu.00269.2014"},{"key":"B36","doi-asserted-by":"publisher","DOI":"10.1093\/nutrit\/nuw053"},{"key":"B37","doi-asserted-by":"publisher","DOI":"10.1111\/j.1751-1097.2006.tb09826.x"},{"key":"B38","doi-asserted-by":"publisher","DOI":"10.1016\/j.jphotobiol.2008.12.003"}],"container-title":["Journal of Applied Physiology"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.physiology.org\/doi\/pdf\/10.1152\/japplphysiol.00501.2018","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2019,9,8]],"date-time":"2019-09-08T23:42:48Z","timestamp":1567986168000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.physiology.org\/doi\/10.1152\/japplphysiol.00501.2018"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2018,10,1]]},"references-count":38,"journal-issue":{"issue":"4","published-print":{"date-parts":[[2018,10,1]]}},"alternative-id":["10.1152\/japplphysiol.00501.2018"],"URL":"https:\/\/doi.org\/10.1152\/japplphysiol.00501.2018","relation":{},"ISSN":["8750-7587","1522-1601"],"issn-type":[{"value":"8750-7587","type":"print"},{"value":"1522-1601","type":"electronic"}],"subject":[],"published":{"date-parts":[[2018,10,1]]}}}