title: Adipose differentiation related protein induces lipid accumulation and lipid droplet formation in hepatic stellate cells.
abstract: The function of adipose differentiation-related protein (ADRP) is known to be the uptake of long-chain fatty acids and formation of lipid droplets in lipid-accumulating cells. We hypothesized that ADRP might stimulate activated hepatic stellate cells (HSCs) to accumulate lipids, resulting in their transition to the quiescent state. In this study, cultured HSCs in fifth passages isolated from rat were infected by adenovirus vector expressing ADRP (Ad.GFP-ADRP), and morphologic and functional changes were evaluated in comparison with control HSCs infected by recombinant adenovirus-expressing beta-galactosidase (Ad.LacZ). In Ad.GFP-ADRP-infected cells only, many tiny lipid droplets were apparent in the cytoplasm, while the outline of the cells was not changed. The ADRP was detected around the lipid droplets. In HSCs with intracellular actin filaments, the staining pattern of the filaments before and after infection with Ad.GFP-ADRP or Ad.LacZ did not differ. The cell proliferation rate was not influenced by infection with Ad.LacZ or Ad.GFP-ADRP. Type I collagen secretion from cells overexpressing ADRP was not significantly different from that of Ad.LacZ-infected cells. In our in vitro study, ADRP overexpression induced the formation of cytoplasmic lipid droplets in activated HSCs but could not convert other characteristics of the activated form into those of the quiescent form.
authors.affiliation: Department of Medicine and Bioregulatory Science, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
authors.forename: Marie
authors.initials: M
authors.lastname: Fukushima
authors.forename: Munechika
authors.initials: M
authors.lastname: Enjoji
authors.forename: Motoyuki
authors.initials: M
authors.lastname: Kohjima
authors.forename: Rie
authors.initials: R
authors.lastname: Sugimoto
authors.forename: Satoshi
authors.initials: S
authors.lastname: Ohta
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Kotoh
authors.forename: Masami
authors.initials: M
authors.lastname: Kuniyoshi
authors.forename: Kunihisa
authors.initials: K
authors.lastname: Kobayashi
authors.forename: Minako
authors.initials: M
authors.lastname: Imamura
authors.forename: Toyoshi
authors.initials: T
authors.lastname: Inoguchi
authors.forename: Makoto
authors.initials: M
authors.lastname: Nakamuta
authors.forename: Hajime
authors.initials: H
authors.lastname: Nawata
mesh_terms: D000199:Actins / Q000378:metabolism; D000256:Adenoviridae; D000273:Adipose Tissue / Q000166:cytology / Q000378:metabolism*; D000818:Animals; D015870:Gene Expression; D005822:Genetic Vectors; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D022781:Hepatocytes / Q000378:metabolism*; D050356:Lipid Metabolism; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D000070780:Perilipin-2; D051381:Rats
chemical_list: D000199:Actins; D008565:Membrane Proteins; D000070780:Perilipin-2; C000602984:Plin2 protein, rat; D049452:Green Fluorescent Proteins