Timothy Joseph McMahon, MD, PhD

Professor of Medicine
Campus mail DUMC 2650, 203 Research Drive, Durham, NC 27710
Phone (919) 668-7762
Email address tim.mcmahon@duke.edu

The McMahon Lab at Duke University and Durham VA Medical Center is investigating novel roles of the red blood cell (RBC) in the circulation. The regulated release of the vasodilator SNO (a form of NO, nitric oxide) by RBCs within the respiratory cycle in mammals optimizes nutrient delivery at multiple levels, especially in the lung (gas exchange) and the peripheral microcirculation (O2 transport to tisses). Deficiency of RBC SNO bioactivity (as in human RBCs banked for transfusion), for example, appears to contribute to the serious lung and circulatory problems associated with RBC transfusion in some settings. We have also demonstrated benefit in the use of treatments that exploit RBCs as a vehicle for delivery of SNOs, in both human patients and in model animals.

RBCs also release ATP in response to stimuli including deformation and hypoxia, and the exported ATP also participates in the maintenance of a healthy circulation, according to mechanisms that we are now unraveling.

We use basic and translational approaches to understand the molecular mechanisms by which these RBC-derived signals effect circulatory changes in human health and disease, particularly in the lung. Disease states driving this research include acute and chronic lung diseases such as sepsis (severe infection), transfusion-related respiratory problems, sickle cell disease, and pulmonary hypertension of adults and newborns.

Funding: VA and NIH.

Education and Training

  • Pulmonary Fellow, Medicine, Duke University, 1996 - 1999
  • Medical Resident, Medicine, Duke University, 1993 - 1996
  • M.D., Tulane University, 1993
  • Ph.D., Tulane University, 1992

Publications

Domowicz, D Lopez, J. A. Herbert, and T. J. McMahon. “Decreased ATP Export from Erythrocytes in Murine Sepsis.” In American Journal of Respiratory and Critical Care Medicine, Vol. 199. AMER THORACIC SOC, 2019.

Scholars@Duke

Zhu, H., I. Akosman, and T. J. McMahon. “Transfusion of Red Blood Cells in Mice with Endothelial Deletion of the S-Nitrosothiol Transporter LAT1.” In American Journal of Respiratory and Critical Care Medicine, Vol. 199. AMER THORACIC SOC, 2019.

Scholars@Duke

Zhang, Lisheng, Jiao-Hui Wu, Tai-Qin Huang, Igor Nepliouev, Leigh Brian, Zhushan Zhang, Virginia Wertman, et al. “Drebrin regulates angiotensin II-induced aortic remodelling..” Cardiovasc Res 114, no. 13 (November 1, 2018): 1806–15. https://doi.org/10.1093/cvr/cvy151.

PMID
29931051
Full Text

Gowdy, K. M., S. W. Reece, K. L. Cuddapah, B. Kilburg-Basnyat, C. Psaltis, A. Hondros, T. J. McMahon, T. Zeczycki, and R. M. Tighe. “CD163 Protects Against Ozone Increased Susceptibility to Bacterial Pneumonia.” In American Journal of Respiratory and Critical Care Medicine, Vol. 197. AMER THORACIC SOC, 2018.

Scholars@Duke

Swaminathan, A., Y. Lokhnygina, H. Zhu, K. Kennedy, S. N. Mason, Z. Kelleher, B. Fee, A. Poms, V. F. Tapson, and T. J. McMahon. “Asymmetric Dimethylarginine and Symmetric Dimethylarginine as Novel Biomarkers in Patients with Pulmonary (Arterial) Hypertension.” In American Journal of Respiratory and Critical Care Medicine, Vol. 197. AMER THORACIC SOC, 2018.

Scholars@Duke

Vostal, Jaroslav G., Paul W. Buehler, Monique P. Gelderman, Abdu I. Alayash, Alan Doctor, James C. Zimring, Simone A. Glynn, et al. “Proceedings of the Food and Drug Administration's public workshop on new red blood cell product regulatory science 2016..” Transfusion 58, no. 1 (January 2018): 255–66. https://doi.org/10.1111/trf.14435.

PMID
29243830
Full Text

Rogers, Stephen C., Laura B. Dosier, Timothy J. McMahon, Hongmei Zhu, David Timm, Hengtao Zhang, Joseph Herbert, et al. “Red blood cell phenotype fidelity following glycerol cryopreservation optimized for research purposes..” Plos One 13, no. 12 (2018). https://doi.org/10.1371/journal.pone.0209201.

PMID
30576340
Full Text

Dosier, Laura Beth Mann, Vikram J. Premkumar, Hongmei Zhu, Izzet Akosman, Michael F. Wempe, and Timothy J. McMahon. “Antagonists of the system L neutral amino acid transporter (LAT) promote endothelial adhesivity of human red blood cells..” Thromb Haemost 117, no. 7 (June 28, 2017): 1402–11. https://doi.org/10.1160/TH16-05-0373.

PMID
28382373
Full Text

Zhu, H., S. E. Hill, J. Caswell, and T. J. McMahon. “Red Blood Cell Hemoglobin-Bound Nitric Oxide In Human Blood Stored For Acute Normovolemic Hemodilution (anh).” In American Journal of Respiratory and Critical Care Medicine, Vol. 195. AMER THORACIC SOC, 2017.

Scholars@Duke

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