Logo for University of Iowa Health Care This logo represents the University of Iowa Health Care

Jonathan Nizar, MD

Contact Information 

Office: 3269B CBRB
Phone: 335-7517
Faculty Profile

Brief description of current research: 

Our lab studies the effect of obesity and diabetes on kidney function and its implications for blood pressure and electrolyte levels in the body. Over years, obesity and diabetes cause progressive damage to the kidney, resulting in chronic kidney disease and eventual kidney failure. Well before that, however, they also distort the primary role of a healthy kidney, to maintain the balance of water, electrolytes, and other chemicals to allow the body to functional normally.

We focus on two questions:

How does obesity and diabetes alter the kidney response to diuretics (common drugs prescribed for high blood pressure and swelling)? These drugs act to block molecular transporters and channels in the kidney that reabsorb electrolytes from the fluid that eventually becomes urine back into the body. Variability in the efficacy of these drugs is well-described and may also change within the same patient over time. Understanding why this happens would be a useful tool for physicians caring for these patients.

How does obesity and diabetes alter the autonomic nervous system’s regulation of kidney function? The autonomic nervous system connects the kidney to the brain and integrates its function with many other organs to control blood pressure, electrolyte balance, energy balance, and many other critical bodily functions.

3 most influential diabetes/obesity/metabolism publications:

  • Nizar JM, Dong W, McClellan RB, Labarca M, Zhou Y, Wong J, Goens DG, Zhao M, Velarde N, Bernstein D, Pellizzon M, Satlin LM, Bhalla V. Na+-sensitive elevation in blood pressure is ENaC independent in diet-induced obesity and insulin resistance. Am J Physiol Renal Physiol. 2016 May 1;310(9):F812-20. doi: 10.1152/ajprenal.00265.2015. Epub 2016 Feb 3. PubMed PMID: 26841823; PubMed Central PMCID: PMC4867314.
  • Nizar JM, Bouby N, Bankir L, Bhalla V. Improved protocols for the study of urinary electrolyte excretion and blood pressure in rodents: use of gel food and stepwise changes in diet composition. Am J Physiol Renal Physiol. 2018 Jun 1;314(6):F1129-F1137. doi: 10.1152/ajprenal.00474.2017. Epub 2018 Jan 10. PubMed PMID: 29357416; PubMed Central PMCID: PMC6032076.
  • Labarca M, Nizar JM, Walczak EM, Dong W, Pao AC, Bhalla V. Harvest and primary culture of the murine aldosterone-sensitive distal nephron. Am J Physiol Renal Physiol. 2015 Jun 1;308(11):F1306-15. doi: 10.1152/ajprenal.00668.2014. Epub 2015 Mar 25. PubMed PMID: 25810438; PubMed Central PMCID: PMC4451330.

Quote: 

I aim to contribute to the dizzying network of patient experience, physician observation, and scientific inquiry that grows and evolves to cure diabetes and hypertension.

 

 

People