• Home
  • Search Results
  • Endoplasmic reticulum stress disrupts lysosomal homeostasis and induces blockade of autophagic flux in human trophoblasts.

Endoplasmic reticulum stress disrupts lysosomal homeostasis and induces blockade of autophagic flux in human trophoblasts.

Scientific reports (2019-08-09)
Akitoshi Nakashima, Shi-Bin Cheng, Tae Kusabiraki, Kenichiro Motomura, Aiko Aoki, Akemi Ushijima, Yosuke Ono, Sayaka Tsuda, Tomoko Shima, Osamu Yoshino, Haruhiko Sago, Kenji Matsumoto, Surendra Sharma, Shigeru Saito
ABSTRACT

Pregnancy is a stress factor culminating into mild endoplasmic reticulum (ER) stress, which is necessary for placental development. However, excessive or chronic ER stress in pre-eclamptic placentas leads to placental dysfunction. The precise mechanisms through which excessive ER stress impacts trophoblasts are not well understood. Here, we showed that ER stress reduces the number of lysosomes, resulting in inhibition of autophagic flux in trophoblast cells. ER stress also disrupted the translocation of lysosomes to the surface of trophoblast cells, and inhibited lysosomal exocytosis, whereby the secretion of lysosomal-associated membrane protein 1 (LAMP1) into culture media was significantly attenuated. In addition, we found that serum LAMP1 and beta-galactosidase levels were significantly decreased in pre-eclampsia patients compared to normal pregnant women, potentially indicating lysosomal dysfunction through ER stress in pre-eclamptic placentas. Thus, we demonstrated that excessive ER stress essentially disrupts homeostasis in trophoblasts in conjunction with autophagy inhibition by lysosomal impairment.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Hydrogen peroxide solution, 30 % (w/w) in H2O, contains stabilizer
Sigma-Aldrich
Trypan Blue solution, 0.4%, liquid, sterile-filtered, suitable for cell culture
Sigma-Aldrich
Protease Inhibitor Cocktail, for use with mammalian cell and tissue extracts, DMSO solution
Sigma-Aldrich
Ponceau S solution, BioReagent, suitable for electrophoresis, 0.1 % (w/v) in 5% acetic acid
Sigma-Aldrich
Phosphatase Inhibitor Cocktail 2, aqueous solution (dark coloration may develop upon storage, which does not affect the activity)
Sigma-Aldrich
Chloroquine diphosphate salt, powder or crystals, 98.5-101.0% (EP)
Sigma-Aldrich
Thapsigargin, ≥98% (HPLC), solid film
Sigma-Aldrich
Sodium tauroursodeoxycholate
Sigma-Aldrich
Anti-α-Tubulin antibody, Mouse monoclonal, clone AA13, purified from hybridoma cell culture