Hepatic stellate cells retain retinoid-laden lipid droplets after cellular transdifferentiation into activated myofibroblasts

Loretta L. Jophlin, Yiannis Koutalos, Chunhe Chen, Vijay Shah, Don C. Rockey

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

Loss of retinyl ester (RE)-rich lipid droplets (LDs) from hepatic stellate cells (HSCs) is cited as a key event in their cellular transdifferentiation to activated, pro-fibrotic myofibroblasts; however, it remains unclear if changes in LD morphology or RE content are causal for transdifferentiation. To better understand LD dynamics in vitro within a common model of HSC activation, we used novel approaches preserving LD morphology and allowing for quantitation of RE. The size and quantity of LDs within in vitro and in vivo bile duct ligation (BDL)-activated HSCs were quantitated using adipocyte differentiation-related protein (ADRP) labeling and oil red o (ORO) staining (gold standard), and RE content was determined using fluorescence microscopy. We found during HSC activation in vitro that LD number differed significantly when measured by ADRP and ORO, respectively (day 1: 56 vs. 5, P = 0.03; day 4: 101 vs. 39, P = 0.03; day 14: 241 vs. 12, P = 0.02). Ex vivo HSCs activated in vivo contained the same number of LDs as day 4 in vitro activated HSCs (118 vs. 101, P = 0.54). Decline in LD RE occurred beyond day 4 in vitro and day 1 ex vivo, after HSC transdifferentiation was underway. Lastly, in situ HSCs examined using electron microscopy show LDs tend to be smaller but are ultimately retained in BDL injured livers. Therefore, we conclude that during HSC transdifferentiation, LDs are not lost but are retained, decreasing in size. Additionally, RE content declines after transdifferentiation is underway. These data suggest that these LD changes are not causal for HSC transdifferentiation.

Original languageEnglish (US)
Pages (from-to)G713-G721
JournalAmerican Journal of Physiology - Gastrointestinal and Liver Physiology
Volume315
Issue number5
DOIs
StatePublished - Nov 2018

Fingerprint

Hepatic Stellate Cells
Myofibroblasts
Retinoids
Esters
Cell Transdifferentiation
Bile Ducts
Adipocytes
Ligation
Oils
Lipid Droplets
Fluorescence Microscopy
Electron Microscopy
Proteins
In Vitro Techniques

Keywords

  • Hepatic stellate cell
  • Lipid droplet
  • Myofibroblast
  • Retinoid
  • Transdifferentiation

ASJC Scopus subject areas

  • Physiology
  • Hepatology
  • Gastroenterology
  • Physiology (medical)

Cite this

Hepatic stellate cells retain retinoid-laden lipid droplets after cellular transdifferentiation into activated myofibroblasts. / Jophlin, Loretta L.; Koutalos, Yiannis; Chen, Chunhe; Shah, Vijay; Rockey, Don C.

In: American Journal of Physiology - Gastrointestinal and Liver Physiology, Vol. 315, No. 5, 11.2018, p. G713-G721.

Research output: Contribution to journalArticle

Jophlin, Loretta L. ; Koutalos, Yiannis ; Chen, Chunhe ; Shah, Vijay ; Rockey, Don C. / Hepatic stellate cells retain retinoid-laden lipid droplets after cellular transdifferentiation into activated myofibroblasts. In: American Journal of Physiology - Gastrointestinal and Liver Physiology. 2018 ; Vol. 315, No. 5. pp. G713-G721.
@article{ffb42dccfddf4c3ca3b32ff2bf85bb0f,
title = "Hepatic stellate cells retain retinoid-laden lipid droplets after cellular transdifferentiation into activated myofibroblasts",
abstract = "Loss of retinyl ester (RE)-rich lipid droplets (LDs) from hepatic stellate cells (HSCs) is cited as a key event in their cellular transdifferentiation to activated, pro-fibrotic myofibroblasts; however, it remains unclear if changes in LD morphology or RE content are causal for transdifferentiation. To better understand LD dynamics in vitro within a common model of HSC activation, we used novel approaches preserving LD morphology and allowing for quantitation of RE. The size and quantity of LDs within in vitro and in vivo bile duct ligation (BDL)-activated HSCs were quantitated using adipocyte differentiation-related protein (ADRP) labeling and oil red o (ORO) staining (gold standard), and RE content was determined using fluorescence microscopy. We found during HSC activation in vitro that LD number differed significantly when measured by ADRP and ORO, respectively (day 1: 56 vs. 5, P = 0.03; day 4: 101 vs. 39, P = 0.03; day 14: 241 vs. 12, P = 0.02). Ex vivo HSCs activated in vivo contained the same number of LDs as day 4 in vitro activated HSCs (118 vs. 101, P = 0.54). Decline in LD RE occurred beyond day 4 in vitro and day 1 ex vivo, after HSC transdifferentiation was underway. Lastly, in situ HSCs examined using electron microscopy show LDs tend to be smaller but are ultimately retained in BDL injured livers. Therefore, we conclude that during HSC transdifferentiation, LDs are not lost but are retained, decreasing in size. Additionally, RE content declines after transdifferentiation is underway. These data suggest that these LD changes are not causal for HSC transdifferentiation.",
keywords = "Hepatic stellate cell, Lipid droplet, Myofibroblast, Retinoid, Transdifferentiation",
author = "Jophlin, {Loretta L.} and Yiannis Koutalos and Chunhe Chen and Vijay Shah and Rockey, {Don C.}",
year = "2018",
month = "11",
doi = "10.1152/ajpgi.00251.2017",
language = "English (US)",
volume = "315",
pages = "G713--G721",
journal = "American Journal of Physiology - Renal Physiology",
issn = "0363-6127",
publisher = "American Physiological Society",
number = "5",

}

TY - JOUR

T1 - Hepatic stellate cells retain retinoid-laden lipid droplets after cellular transdifferentiation into activated myofibroblasts

AU - Jophlin, Loretta L.

AU - Koutalos, Yiannis

AU - Chen, Chunhe

AU - Shah, Vijay

AU - Rockey, Don C.

PY - 2018/11

Y1 - 2018/11

N2 - Loss of retinyl ester (RE)-rich lipid droplets (LDs) from hepatic stellate cells (HSCs) is cited as a key event in their cellular transdifferentiation to activated, pro-fibrotic myofibroblasts; however, it remains unclear if changes in LD morphology or RE content are causal for transdifferentiation. To better understand LD dynamics in vitro within a common model of HSC activation, we used novel approaches preserving LD morphology and allowing for quantitation of RE. The size and quantity of LDs within in vitro and in vivo bile duct ligation (BDL)-activated HSCs were quantitated using adipocyte differentiation-related protein (ADRP) labeling and oil red o (ORO) staining (gold standard), and RE content was determined using fluorescence microscopy. We found during HSC activation in vitro that LD number differed significantly when measured by ADRP and ORO, respectively (day 1: 56 vs. 5, P = 0.03; day 4: 101 vs. 39, P = 0.03; day 14: 241 vs. 12, P = 0.02). Ex vivo HSCs activated in vivo contained the same number of LDs as day 4 in vitro activated HSCs (118 vs. 101, P = 0.54). Decline in LD RE occurred beyond day 4 in vitro and day 1 ex vivo, after HSC transdifferentiation was underway. Lastly, in situ HSCs examined using electron microscopy show LDs tend to be smaller but are ultimately retained in BDL injured livers. Therefore, we conclude that during HSC transdifferentiation, LDs are not lost but are retained, decreasing in size. Additionally, RE content declines after transdifferentiation is underway. These data suggest that these LD changes are not causal for HSC transdifferentiation.

AB - Loss of retinyl ester (RE)-rich lipid droplets (LDs) from hepatic stellate cells (HSCs) is cited as a key event in their cellular transdifferentiation to activated, pro-fibrotic myofibroblasts; however, it remains unclear if changes in LD morphology or RE content are causal for transdifferentiation. To better understand LD dynamics in vitro within a common model of HSC activation, we used novel approaches preserving LD morphology and allowing for quantitation of RE. The size and quantity of LDs within in vitro and in vivo bile duct ligation (BDL)-activated HSCs were quantitated using adipocyte differentiation-related protein (ADRP) labeling and oil red o (ORO) staining (gold standard), and RE content was determined using fluorescence microscopy. We found during HSC activation in vitro that LD number differed significantly when measured by ADRP and ORO, respectively (day 1: 56 vs. 5, P = 0.03; day 4: 101 vs. 39, P = 0.03; day 14: 241 vs. 12, P = 0.02). Ex vivo HSCs activated in vivo contained the same number of LDs as day 4 in vitro activated HSCs (118 vs. 101, P = 0.54). Decline in LD RE occurred beyond day 4 in vitro and day 1 ex vivo, after HSC transdifferentiation was underway. Lastly, in situ HSCs examined using electron microscopy show LDs tend to be smaller but are ultimately retained in BDL injured livers. Therefore, we conclude that during HSC transdifferentiation, LDs are not lost but are retained, decreasing in size. Additionally, RE content declines after transdifferentiation is underway. These data suggest that these LD changes are not causal for HSC transdifferentiation.

KW - Hepatic stellate cell

KW - Lipid droplet

KW - Myofibroblast

KW - Retinoid

KW - Transdifferentiation

UR - http://www.scopus.com/inward/record.url?scp=85055078808&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85055078808&partnerID=8YFLogxK

U2 - 10.1152/ajpgi.00251.2017

DO - 10.1152/ajpgi.00251.2017

M3 - Article

C2 - 30024770

AN - SCOPUS:85055078808

VL - 315

SP - G713-G721

JO - American Journal of Physiology - Renal Physiology

JF - American Journal of Physiology - Renal Physiology

SN - 0363-6127

IS - 5

ER -