Palmitic Acid Induces Endoplasmic Reticulum Stress In AML12 Liver Cells

Year 2018, Volume: 31 Issue: 1, 40 - 46, 28.01.2018

Tugce Demirel Saime Batirel

https://doi.org/10.5472/marumj.362169

Cited By: 2

Abstract

Objectives: Nonalcoholic fatty liver disease (NAFLD) is characterized by increased fatty acid levels in
serum and liver. The mechanism of NAFLD is unclear. The role of endoplasmic
reticulum (ER) stress attracts attention. First aim of this study was to design
an in vitro
NAFLD model. The effects of palmitic acid (PA) alone or combination with
oleic acid (OA) on intracellular reactive oxygen species (ROS) production and
ER stress in liver cells were investigated as a second aim.

         
Materials and Methods: AML12 cells were exposed to PA and/or OA with
different concentrations and combinations.
Intracellular lipids and cell viability were detected with Oil red O staining
and WST-1 assay respectively. Intracellular ROS accumulation was measured by flow
cytometry analysis. Expression of ER stress proteins, BiP and IRE1, were
evaluated with western blot analysis.

       Results: Intracellular lipid content was increased in all
treated groups. Cell viability was decreased whereas ROS generation and
expression of the ER stress proteins were increased in cells treated with PA. However
these effects were not observed in the cells treated with OA+PA combination.

       Conclusion: PA
induces ROS generation and the ER stress pathway that
is mediated by IRE1 in liver cells. Addition of OA enhances these
effects. 

Keywords

Nonalcoholic fatty liver disease, palmitic acid, oleic acid, endoplasmic reticulum stress

Palmitik Asit AML12 Karaciğer Hücrelerinde Endoplazmik Retikulum Stresi Uyarır

Abstract

Amaçlar: Nonalkolik yağlı karaciğer hastalığı (NAYKH),
serum ve karaciğerde artmış yağ asit seviyeleri ile karakterizedir. NAYKH’nin mekanizması
net değildir. Endoplazmik retikulum (ER) stresin rolü dikkat çekmektedir. Bu çalışmanın ilk amacı, bir in vitro NAYKH modeli dizayn etmekti.
İkinci hedef olarak, palmitik asid (PA)’in yalnız veya oleik asit (OA) ile
kombinasyonunun, karaciğer hücrelerinde, reaktif oksijen türleri (ROT) oluşumu ve
ER stresi üzerindeki etkileri araştırıldı.

        Gereçler ve Yöntemler:
AML12 hücreleri, farklı
konsantrasyon ve kombinasyonlarda, OA ve PA ile muamele edildi. Hücre içi
lipidler ve hücre canlılığı, sırasıyla Oil red O boyaması ve WST-1 analiziyle saptandı.
Hücre içi ROT birikimi akış sitometrisi ile ölçüldü. ER stres proteinleri, BiP
ve IRE1, western blot analizi ile değerlendirildi.

       Bulgular: Hücre içi lipit içeriği tüm uygulamaya maruz kalmış
gruplarda arttı. PA ile muamele edilmiş hücrelerde, hücre canlılığı azaldı ve ROT
üretimi  ve ER stres proteinlerin
ekspresyonu arttı. Ancak bu etkiler OA+PA kombinasyonu ile muamele edilmiş  hücrelerde gözlenmedi.

       Sonuç: PA, karaciğer hücrelerinde, ROS üretimini ve IRE1
aracılı ER stres yolağını indükler. Ama OA eklenmesi bu etkileri iyileştirir.

Keywords

Nonalkolik yağlı karaciğer hastalığı, palmitik asit, oleik asit, endoplazmik retikulum stres

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