Patterns of gene and metabolite define the effects of extracellular osmolality on kidney collecting duct.
To investigate the effects of changes in extracellular osmolality on the function of kidney collecting duct cells, particularly on water and sodium reabsorption in the conditions of diuresis and antidiuresis, we generated transcriptome and metabolome profiles of primary cultured inner medullary collecting duct (IMCD) cells. They were grown in hyperosmolar culture medium (640 mOsm) for 4 days and then exposed to either reduced (300 mOsm) or same osmolality for 1 or 2 days more. Integrated analysis of the transcriptome and metabolome revealed that decreased extracellular osmolality was associated with decreased levels of organic osmolytes, glucose, intermediates of citric acid cycle, and branched-chain amino acids (BCAA) in IMCD cells, along with significantly decreased gene expression and protein abundance of P-type transporters (ATP1B1), ABC transporters (ABCC5 and ABCG1), and insulin signaling pathways (IRS2). Quantitative real-time RT-PCR and semiquantitative immunoblotting confirmed the changes of transcript levels of differentially expressed genes and protein levels. Taken together, integrated analysis of omics data demonstrated that water and sodium reabsorption could be reduced by decreased extracellular osmolality per se, through decreased levels of ABC transporters and IRS2, which play a potential role in the transport of organic osmolytes, BCAA, glucose, and trafficking of epithelial sodium channel.
Department of Biochemistry and Cell Biology, School of Medicine, Kyungpook National University, Taegu, Korea.
Hyo-Jung
HJ
Choi
Yu-Jeong
YJ
Yoon
Yong-Kook
YK
Kwon
Yu-Jung
YJ
Lee
Sehyun
S
Chae
Daehee
D
Hwang
Geum-Sook
GS
Hwang
Tae-Hwan
TH
Kwon
D000818:Animals; D002478:Cells, Cultured; D016000:Cluster Analysis; D003470:Culture Media; D020869:Gene Expression Profiling; D005786:Gene Expression Regulation; D007685:Kidney Tubules, Collecting / Q000166:cytology / Q000378:metabolism* / Q000502:physiology; D009682:Magnetic Resonance Spectroscopy; D008297:Male; D053858:Metabolic Networks and Pathways; D055442:Metabolome; D015999:Multivariate Analysis; D009994:Osmolar Concentration; D010363:Pattern Recognition, Automated; D025341:Principal Component Analysis; D020543:Proteome / Q000235:genetics / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D060888:Real-Time Polymerase Chain Reaction; D055049:Salt Tolerance; D018709:Statistics, Nonparametric; D059467:Transcriptome
D003470:Culture Media; D020543:Proteome