{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,8]],"date-time":"2026-07-08T02:49:44Z","timestamp":1783478984802,"version":"3.55.0"},"reference-count":40,"publisher":"MDPI AG","issue":"11","license":[{"start":{"date-parts":[[2019,11,14]],"date-time":"2019-11-14T00:00:00Z","timestamp":1573689600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100013129","name":"Ministry of SMEs and Startups","doi-asserted-by":"publisher","award":["P0002990"],"award-info":[{"award-number":["P0002990"]}],"id":[{"id":"10.13039\/501100013129","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>Obesity induces inflammation both in the adipose tissue and the brain. Activated macrophage infiltration, polarization of macrophages to a more inflammatory type (M1), and increased levels of pro-inflammatory cytokines are related to brain inflammation, which induces leptin resistance in the brain. Pyrogallol-phloroglucinol-6,6-bieckol (PPB), a compound from Ecklonia cava, has anti-inflammatory effects. In this study, we evaluated the effects of PPB effect M1 polarization and inflammation and its ability to restore the effects of leptin, such as a decrease in appetite and body weight. We administered PPB to diet-induced obesity (DIO) and leptin-deficient (ob\/ob) mice, evaluated macrophage activation, polarization, and changes of inflammatory cytokine level in adipose tissue and brain, and determined the effect of PPB on leptin resistance or leptin sensitivity in the brain. The levels of activated macrophage marker, M1\/M2, and pro-inflammatory cytokines were increased in the adipose tissue and brain of DIO and ob\/ob mice than control. TLR4 expression, endoplasmic reticulum (ER) stress, and NF-\u03baB expression in the brain of DIO and ob\/ob mice were also increased; this increase was related to the upregulation of SOCS3 and decreased phosphorylated STAT3, which decreased leptin sensitivity in the brain. PPB decreased inflammation in the brain, restored leptin sensitivity, and decreased food intake and weight gain in both DIO and ob\/ob mice.<\/jats:p>","DOI":"10.3390\/nu11112773","type":"journal-article","created":{"date-parts":[[2019,11,15]],"date-time":"2019-11-15T11:25:56Z","timestamp":1573817156000},"page":"2773","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":24,"title":["Attenuation of Inflammation and Leptin Resistance by Pyrogallol-Phloroglucinol-6,6-Bieckol on in the Brain of Obese Animal Models"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-9104-3991","authenticated-orcid":false,"given":"Myeongjoo","family":"Son","sequence":"first","affiliation":[{"name":"Department of Anatomy &amp; Cell Biology, Gachon University College of Medicine, Incheon 21565, Korea"},{"name":"Functional Cellular Networks Laboratory, College of Medicine, Department of Medicine, Graduate School and Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon 21999, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Seyeon","family":"Oh","sequence":"additional","affiliation":[{"name":"Functional Cellular Networks Laboratory, College of Medicine, Department of Medicine, Graduate School and Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon 21999, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Junwon","family":"Choi","sequence":"additional","affiliation":[{"name":"Department of Anatomy &amp; Cell Biology, Gachon University College of Medicine, Incheon 21565, Korea"},{"name":"Functional Cellular Networks Laboratory, College of Medicine, Department of Medicine, Graduate School and Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon 21999, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ji Tae","family":"Jang","sequence":"additional","affiliation":[{"name":"Aqua Green Technology Co., Ltd., Smart Bldg., Jeju Science Park, Jeju 63309, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chang Hu","family":"Choi","sequence":"additional","affiliation":[{"name":"Department of Thoracic and Cardiovascular Surgery, Gachon University Gil Medical Center, Gachon University, Incheon 21565, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kook Yang","family":"Park","sequence":"additional","affiliation":[{"name":"Department of Thoracic and Cardiovascular Surgery, Gachon University Gil Medical Center, Gachon University, Incheon 21565, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kuk Hui","family":"Son","sequence":"additional","affiliation":[{"name":"Department of Thoracic and Cardiovascular Surgery, Gachon University Gil Medical Center, Gachon University, Incheon 21565, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kyunghee","family":"Byun","sequence":"additional","affiliation":[{"name":"Department of Anatomy &amp; Cell Biology, Gachon University College of Medicine, Incheon 21565, Korea"},{"name":"Functional Cellular Networks Laboratory, College of Medicine, Department of Medicine, Graduate School and Lee Gil Ya Cancer and Diabetes Institute, Gachon University, Incheon 21999, Korea"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2019,11,14]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"30","DOI":"10.3389\/fendo.2017.00030","article-title":"The leptin receptor complex: Heavier than expected?","volume":"8","author":"Wauman","year":"2017","journal-title":"Front. 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