{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,28]],"date-time":"2026-09-28T22:09:43Z","timestamp":1790633383707,"version":"4.1.0"},"reference-count":31,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2021,7,9]],"date-time":"2021-07-09T00:00:00Z","timestamp":1625788800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["IJMS"],"abstract":"<jats:p>The purpose of the present study was to investigate molecular compositions of lipid droplets changing in live hepatic cells stimulated with major fatty acids in the human body, i.e., palmitic, stearic, oleic, and linoleic acids. HepG2 cells were used as the model hepatic cells. Morphological changes of lipid droplets were observed by optical microscopy and transmission electron microscopy (TEM) during co-cultivation with fatty acids up to 5 days. The compositional changes in the fatty chains included in the lipid droplets were analyzed via Raman spectroscopy and chemometrics. The growth curves of the cells indicated that palmitic, stearic, and linoleic acids induced cell death in HepG2 cells, but oleic acid did not. Microscopic observations suggested that the rates of fat accumulation were high for oleic and linoleic acids, but low for palmitic and stearic acids. Raman analysis indicated that linoleic fatty chains taken into the cells are modified into oleic fatty chains. These results suggest that the signaling pathway of cell death is independent of fat stimulations. Moreover, these results suggest that hepatic cells have a high affinity for linoleic acid, but linoleic acid induces cell death in these cells. This may be one of the causes of inflammation in nonalcoholic fatty liver disease (NAFLD).<\/jats:p>","DOI":"10.3390\/ijms22147378","type":"journal-article","created":{"date-parts":[[2021,7,9]],"date-time":"2021-07-09T10:50:38Z","timestamp":1625827838000},"page":"7378","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":34,"title":["Raman Study on Lipid Droplets in Hepatic Cells Co-Cultured with Fatty Acids"],"prefix":"10.3390","volume":"22","author":[{"given":"Pradjna N.","family":"Paramitha","sequence":"first","affiliation":[{"name":"School of Biological and Environmental Sciences, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, Hyogo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Riki","family":"Zakaria","sequence":"additional","affiliation":[{"name":"School of Biological and Environmental Sciences, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, Hyogo, Japan"},{"name":"Department of Biology, Universitas Padjadjaran, Jl. Raya Bandung Sumedang KM 21, Jatinangor, Sumedang 45363, Indonesia"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anisa","family":"Maryani","sequence":"additional","affiliation":[{"name":"School of Biological and Environmental Sciences, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, Hyogo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yukako","family":"Kusaka","sequence":"additional","affiliation":[{"name":"School of Biological and Environmental Sciences, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, Hyogo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bibin B.","family":"Andriana","sequence":"additional","affiliation":[{"name":"School of Biological and Environmental Sciences, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, Hyogo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kosuke","family":"Hashimoto","sequence":"additional","affiliation":[{"name":"School of Biological and Environmental Sciences, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, Hyogo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8694-4579","authenticated-orcid":false,"given":"Hiromitsu","family":"Nakazawa","sequence":"additional","affiliation":[{"name":"School of Science, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, Hyogo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Satoru","family":"Kato","sequence":"additional","affiliation":[{"name":"School of Science, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, Hyogo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4202-5401","authenticated-orcid":false,"given":"Hidetoshi","family":"Sato","sequence":"additional","affiliation":[{"name":"School of Biological and Environmental Sciences, Kwansei Gakuin University, 2-1 Gakuen, Sanda 669-1337, Hyogo, Japan"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2021,7,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"656","DOI":"10.1038\/nrgastro.2013.183","article-title":"NAFLD, NASH and liver cancer","volume":"10","author":"Michelotti","year":"2013","journal-title":"Nat. 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