G-protein βγ subunit dimers modulate kidney repair after ischemia-reperfusion injury in rats.

Abstract

Heterotrimeric G-proteins play a crucial role in the control of renal epithelial cell function during homeostasis and in response to injury. In this report, G-protein βγ subunit (Gβγ) dimer activity was evaluated during the process of tubular repair after renal ischemia-reperfusion injury (IRI) in male Sprague Dawley rats. Rats were treated with a small molecule inhibitor of Gβγ activity, gallein (30 or 100 mg/kg), 1 hour after reperfusion and every 24 hours for 3 additional days. After IRI, renal dysfunction was prolonged after the high-dose gallein treatment in comparison with vehicle treatment during the 7-day recovery period. Renal tubular repair in the outer medulla 7 days after IRI was significantly (P < 0.001) attenuated after treatment with high-dose gallein (100 mg/kg) in comparison with low-dose gallein (30 mg/kg), or the vehicle and fluorescein control groups. Gallein treatment significantly reduced (P < 0.05) the number of proliferating cell nuclear antigen-positive tubular epithelial cells at 24 hours after the ischemia-reperfusion phase in vivo. In vitro application of gallein on normal rat kidney (NRK-52E) proximal tubule cells significantly reduced (P < 0.05) S-phase cell cycle entry compared with vehicle-treated cells as determined by 5'-bromo-2'-deoxyuridine incorporation. Taken together, these data suggest that Gβγ signaling contributes to the maintenance and repair of renal tubular epithelium and may be a novel therapeutic target for the development of drugs to treat acute kidney injury.

• Authors: Sarah M White, Lauren M North, Emily Haines, Megan Goldberg, Lydia M Sullivan, Jeffrey D Pressly, David S Weber, Frank Park, Kevin R Regner
• Journal: Molecular pharmacology (Mol Pharmacol) Vol. 86 Issue 4 Pg. 369-77 (Oct 2014) ISSN: 1521-0111 [Electronic] United States
• PMID: 25028481 (Publication Type: Journal Article, Research Support, N.I.H., Extramural)
• Copyright: Copyright © 2014 by The American Society for Pharmacology and Experimental Therapeutics.

Chemical References

• G-protein Beta gamma
• GTP-Binding Protein beta Subunits
• GTP-Binding Protein gamma Subunits
• Xanthenes
• gallein

Topics

• Animals
• Cardio-Renal Syndrome (drug therapy, metabolism)
• Cell Line
• Cell Movement
• Cell Proliferation
• Epithelial Cells (drug effects, metabolism, physiology)
• GTP-Binding Protein beta Subunits (antagonists & inhibitors, metabolism)
• GTP-Binding Protein gamma Subunits (antagonists & inhibitors, metabolism)
• Kidney (drug effects, metabolism, pathology)
• Male
• Protein Multimerization
• Rats
• Rats, Sprague-Dawley
• Reperfusion Injury (drug therapy, metabolism)
• Xanthenes (pharmacology, therapeutic use)