Skip to Content
Merck
  • Fatty acid-bearing albumin but not fatty acid-depleted albumin induces HIF-1 activation in human renal proximal tubular epithelial cell line HK-2.

Fatty acid-bearing albumin but not fatty acid-depleted albumin induces HIF-1 activation in human renal proximal tubular epithelial cell line HK-2.

Biochemical and biophysical research communications (2014-06-14)
Junya Nagai, Ayaka Yamamoto, Yuki Katagiri, Ryoko Yumoto, Mikihisa Takano
ABSTRACT

Recently, we found that albumin overload induces expression of the transcription factor hypoxia-inducible factor-1α (HIF-1α) protein and several HIF-1 target genes in human renal proximal tubular epithelial cell line HK-2. In this study, the role of albumin-bound fatty acids in the albumin-induced HIF-1 activation was studied. The enhancing effect of fatty acid-bearing human serum albumin [FA(+)HSA] treatment on HIF-1α protein expression was much greater than that of fatty acid-depleted human serum albumin [FA(-)HSA] treatment. The FA(+)HSA treatment induced HIF-1 target gene mRNAs such as those of glucose transporter 1 (GLUT1), glyceraldehyde 3-phosphate dehydrogenase (GAPDH), and breast cancer resistance protein (BCRP) in concentration-dependent manners, while FA(-)HSA caused no significant increases in these mRNAs. Consistent with increased GLUT1 mRNA, GLUT1 protein expression and GLUT inhibitor cytochalasin B-sensitive d-[(3)H]glucose uptake activity were significantly enhanced by treatment with FA(+)HSA, but not with FA(-)HSA. These findings indicate that fatty acids bound to albumin play a crucial role in albumin-induced HIF-1 activation followed by changes in HIF-1 target gene expression and protein product activity.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
Cobalt(II) chloride hexahydrate, suitable for plant cell culture
Sigma-Aldrich
Cobalt(II) chloride hexahydrate, BioReagent, suitable for cell culture, suitable for insect cell culture
Sigma-Aldrich
Cobalt(II) chloride hexahydrate, reagent grade
Sigma-Aldrich
Cobalt(II) chloride hexahydrate, puriss. p.a., ACS reagent, reag. Ph. Eur., 98-102%
Sigma-Aldrich
Cobalt(II) chloride hexahydrate, ACS reagent, 98%