Joe GN Garcia
Professor, BIO5 Institute
Professor, Internal Medicine
Professor, Medicine
Professor, Pharmacology and Toxicology
Professor, Physiological Sciences - GIDP
Professor, Physiology
Primary Department
Department Affiliations
(520) 626-3151
Work Summary
The Garcia laboratory works to understand the molecular mechanisms of lung inflammatory processes, particularly those producing lung edema or vascular leak. The laboratory focus is to investigate gene discovery, protein function assessment, SNP discovery, genetic manipulation, in vivo testing, and candidate gene and biomarker identification, working to translate basic research into potential novel clinical therapies.
Research Interest
Dr. Garcia is an authority on the genetic basis of inflammatory lung disease (with an emphasis on health disparities) and on the mechanistic basis of lung vascular permeability. Using bench-to-bedside approaches, his lab has explored novel methods to prevent vascular leak and to restore endothelial cell barrier function and vascular integrity. This expertise in lung inflammation and vascular permeability provides a natural linkage to interrogation of lung vascular contribution to the development of lung metastases. Leveraging their genomic expertise, in recent years, Dr. Garcia's lab has identified vascular genes whose products are key participants in inflammatory lung injury that also play a role in cancer development. They have developed lung endothelial inflammatory gene expression profiles as well as diagnostic gene signatures influenced by MYLK and NAMPT that impact lung and breast cancer prognosis. This work with NAMPT led to development of a therapeutic NAMPT neutralizing antibody that has shown promise in treating lung cancer, melanoma, and chronic lymphocytic leukemia. Finally, Dr. Garcia's lab is also interested in the untoward effect of thoracic radiation and has been examining strategies designed to attenuate radiation–induced pneumonits, fibrosis and vascular leak. These collaborative and highly translational cancer research efforts have bolstered the overall mission of the University of Arizona Cancer Center.

Publications

Yuan, J., Makino, A., Garcia, J. G., Mcdermott, K. M., Rischard, F., Desai, A., Black, S., Khalpey, Z. I., Cordery, A. G., Sun, X., Tang, H., Babicheva, A., Dash, S., Yamamura, H., Yamamura, A., Ayon, R. J., & Song, S. (2017). Capsaicin-induced Ca2+ signaling is enhanced via upregulated TRPV1 channels in pulmonary artery smooth muscle cells from patients with idiopathic PAH. American journal of physiology. Lung cellular and molecular physiology, 312(3), L309-L325.

Capsaicin is an active component of chili pepper and a pain relief drug. Capsaicin can activate transient receptor potential vanilloid 1 (TRPV1) channels to increase cytosolic Ca2+ concentration ([Ca2+]cyt). A rise in [Ca2+]cyt in pulmonary artery smooth muscle cells (PASMCs) is an important stimulus for pulmonary vasoconstriction and vascular remodeling. In this study, we observed that a capsaicin-induced increase in [Ca2+]cyt was significantly enhanced in PASMCs from patients with idiopathic pulmonary arterial hypertension (IPAH) compared with normal PASMCs from healthy donors. In addition, the protein expression level of TRPV1 in IPAH PASMCs was greater than in normal PASMCs. Increasing the temperature from 23 to 43°C, or decreasing the extracellular pH value from 7.4 to 5.9 enhanced capsaicin-induced increases in [Ca2+]cyt; the acidity (pH 5.9)- and heat (43°C)-mediated enhancement of capsaicin-induced [Ca2+]cyt increases were greater in IPAH PASMCs than in normal PASMCs. Decreasing the extracellular osmotic pressure from 310 to 200 mOsmol/l also increased [Ca2+]cyt, and the hypo-osmolarity-induced rise in [Ca2+]cyt was greater in IPAH PASMCs than in healthy PASMCs. Inhibition of TRPV1 (with 5'-IRTX or capsazepine) or knockdown of TRPV1 (with short hairpin RNA) attenuated capsaicin-, acidity-, and osmotic stretch-mediated [Ca2+]cyt increases in IPAH PASMCs. Capsaicin induced phosphorylation of CREB by raising [Ca2+]cyt, and capsaicin-induced CREB phosphorylation were significantly enhanced in IPAH PASMCs compared with normal PASMCs. Pharmacological inhibition and knockdown of TRPV1 attenuated IPAH PASMC proliferation. Taken together, the capsaicin-mediated [Ca2+]cyt increase due to upregulated TRPV1 may be a critical pathogenic mechanism that contributes to augmented Ca2+ influx and excessive PASMC proliferation in patients with IPAH.

Khalpey, Z. I., Smolenski, R. T., Runyan, R. B., Smith, R., Garcia, J. G., Maltais, S. S., Schmitto, J. D., Beaudry, C., Desai, A., Betterton, E. A., Johnson, K., Dicken, D. S., Pilikian, T., Sweitzer, N. K., & Mikail, P. (2017). Stem cell-liquid matrix therapy may provide a bridge to regeneration in patients with cardiac mechanical circulatory support. Journal of Heart and Lung Transplantation..
Desai, A., Garcia, J. G., Yuan, J., Jacobson, J. J., Nair, V., Mitra, S., Tang, H., Gupta, G., & Gupta, A. (2017). Inhibition of the deubiquitinase, UCHL1, attenuates pulmonary hypertension.. American J Respiratory Critical Care Medicine.
Gross, C., Kellner, M., Wang, T., Lu, Q., Sun, X., Kangath, A., Zemskov, E., Kumar, S., Desai, A., Aggarwal, S., Golchov, B., Klinger, C., Verin, A. D., Catravas, J. D., Jacobsen, J. R., Yuan, J., Rafikov, R., Garcia, J. G., & Black, S. (2016). Lipopolysaccharide Induced Acute Lung Injury Involves the Nuclear Factor Kappa B Mediated Downregulation of the Transcription Factor SOX-18. Am J Respir Cell Mol Biol..
Champion, H. C., Champion, H. C., Vanderpool, R., Vanderpool, R., Garcia, J. G., Garcia, J. G., Yuan, J., Yuan, J., Abidov, A., Abidov, A., Desai, A., Desai, A., Knapp, S. M., Knapp, S. M., Knoper, S. R., Knoper, S. R., Hansen, L., Hansen, L., Simon, M., , Simon, M., et al. (2017). Treprostinil decreases right ventricular contractility but improves ejection fraction and exercise capacity in pulmonary arterial hypertension. European Respiratory J.