{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,19]],"date-time":"2026-09-19T21:12:45Z","timestamp":1789852365132,"version":"4.0.1"},"reference-count":29,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2025,6,12]],"date-time":"2025-06-12T00:00:00Z","timestamp":1749686400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Grant-in-Aid for Early Career Scientists","award":["23K15292"],"award-info":[{"award-number":["23K15292"]}]},{"name":"Grant-in-Aid for Early Career Scientists","award":["20H03568"],"award-info":[{"award-number":["20H03568"]}]},{"name":"Grant-in-Aid for Early Career Scientists","award":["22H02956"],"award-info":[{"award-number":["22H02956"]}]},{"name":"Grant-in-Aid for Early Career Scientists","award":["23K20320"],"award-info":[{"award-number":["23K20320"]}]},{"name":"Grant-in-Aid for Early Career Scientists","award":["23K24217"],"award-info":[{"award-number":["23K24217"]}]},{"name":"Grant-in-Aid for Early Career Scientists","award":["24K02265"],"award-info":[{"award-number":["24K02265"]}]},{"name":"Grant-in-Aid for Scientific Research (B)","award":["23K15292"],"award-info":[{"award-number":["23K15292"]}]},{"name":"Grant-in-Aid for Scientific Research (B)","award":["20H03568"],"award-info":[{"award-number":["20H03568"]}]},{"name":"Grant-in-Aid for Scientific Research (B)","award":["22H02956"],"award-info":[{"award-number":["22H02956"]}]},{"name":"Grant-in-Aid for Scientific Research (B)","award":["23K20320"],"award-info":[{"award-number":["23K20320"]}]},{"name":"Grant-in-Aid for Scientific Research (B)","award":["23K24217"],"award-info":[{"award-number":["23K24217"]}]},{"name":"Grant-in-Aid for Scientific Research (B)","award":["24K02265"],"award-info":[{"award-number":["24K02265"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Cells"],"abstract":"<jats:p>Aging is associated with altered itch perception, potentially due to changes in neuronal function and pruriceptive signaling. The underlying mechanisms, however, remain unclear. We investigated age-related differences in itch sensitivity at behavioral, cellular, and molecular levels. Young and old mice were intradermally injected with various pruritogens, including small molecules (histamine, chloroquine, and serotonin) and peptides (BAM8\u201322, AY-NH2, and SLIGRL-NH2). Scratching behavior and mechanical itch sensitivity were assessed, and calcium imaging was used to evaluate sensory neuron responses in the dorsal root ganglia. Additionally, immunofluorescence staining was performed to analyze the expression of TRPV1 and Cav3.2. Old mice exhibited reduced scratching behavior following injections, and their neuronal responses to histamine and chloroquine were diminished. Although all treated groups showed increased mechanical alloknesis, the effect was less pronounced in old animals. The expression of TRPV1 and Cav3.2 was also reduced in dorsal root ganglia neurons of old mice. These findings suggest that aging impairs both functional responsiveness and molecular signaling in sensory neurons, contributing to reduced chemical itch sensitivity in aged individuals.<\/jats:p>","DOI":"10.3390\/cells14120889","type":"journal-article","created":{"date-parts":[[2025,6,12]],"date-time":"2025-06-12T07:44:23Z","timestamp":1749714263000},"page":"889","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["Decreased Responsiveness to Chemical Itch in Old Mice"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-7407-4043","authenticated-orcid":false,"given":"Qiaofeng","family":"Zhao","sequence":"first","affiliation":[{"name":"Juntendo Itch Research Center (JIRC), Institute for Environmental and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, Chiba 279-0021, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1254-1803","authenticated-orcid":false,"given":"Mitsutoshi","family":"Tominaga","sequence":"additional","affiliation":[{"name":"Juntendo Itch Research Center (JIRC), Institute for Environmental and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, Chiba 279-0021, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3606-245X","authenticated-orcid":false,"given":"Sumika","family":"Toyama","sequence":"additional","affiliation":[{"name":"Juntendo Itch Research Center (JIRC), Institute for Environmental and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, Chiba 279-0021, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kotaro","family":"Honda","sequence":"additional","affiliation":[{"name":"Juntendo Itch Research Center (JIRC), Institute for Environmental and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, Chiba 279-0021, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Eriko","family":"Komiya","sequence":"additional","affiliation":[{"name":"Juntendo Itch Research Center (JIRC), Institute for Environmental and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, Chiba 279-0021, Japan"},{"name":"Department of Functional Morphology, Faculty of Pharmacy, Juntendo University, Chiba 279-0013, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3477-5715","authenticated-orcid":false,"given":"Yayoi","family":"Kamata","sequence":"additional","affiliation":[{"name":"Juntendo Itch Research Center (JIRC), Institute for Environmental and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, Chiba 279-0021, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7565-6889","authenticated-orcid":false,"given":"Hang","family":"Ma","sequence":"additional","affiliation":[{"name":"Department of Biomedical and Pharmaceutical Sciences, College of Pharmacy, University of Rhode Island, Kingston, RI 02881, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0644-0504","authenticated-orcid":false,"given":"Kenji","family":"Takamori","sequence":"additional","affiliation":[{"name":"Juntendo Itch Research Center (JIRC), Institute for Environmental and Gender-Specific Medicine, Juntendo University Graduate School of Medicine, Chiba 279-0021, Japan"},{"name":"Department of Dermatology, Juntendo University Urayasu Hospital, Chiba 279-0021, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2025,6,12]]},"reference":[{"key":"ref_1","first-page":"672","article-title":"The prevalence of skin diseases in the elderly: Analysis of 4099 geriatric patients","volume":"45","author":"Hayran","year":"2005","journal-title":"Int. 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