Katrina M Miranda
Associate Professor, BIO5 Institute
Associate Professor, Chemistry and Biochemistry-Sci
Primary Department
(520) 626-3655
Work Summary
We seek to produce new drugs that harness molecules produced during the natural immune response in order to treat cancer and pain. Such compounds may also provide new treatments for heart failure and alcoholism.
Research Interest
Katrina Miranda, PhD, claims nitric oxide (NO), which is synthesized in the body via enzymatic oxidation of L-arginine, is critical to numerous physiological functions, but also can contribute to the severity of diseases such as cancer or pathophysiological conditions such as stroke. This diversity in the responses to NO biosynthesis is a reflection of the diverse chemistry of NO. For instance, NO can alter the function of enzymes by binding to metal centers. This type of interaction could result in outcomes as disparate as control of blood pressure or death of an invading bacterium. NO can also be readily converted to higher nitrogen oxides such as N2O3 or ONOOH, which have very different chemical and biological properties. The ultimate result will depend upon numerous factors, particularly the location and concentration of NO produced. Therefore, site-specific modulation of NO concentration offers intriguing therapeutic possibilities for an ever expanding list of diseases, including cancer, heart failure and stroke. As a whole, Dr. Miranda is interested in elucidating the fundamental molecular redox chemistry of NO and in developing compounds to deliver or scavenge NO and other nitrogen oxides. These projects are designed to answer questions of potential medical importance through a multi-disciplinary approach, including analytical, synthetic, inorganic and biochemical techniques.The project categories include five major disciplines. First, she will work on the development and utilization of analytical techniques for detection and measurement of NO and other nitrogen oxides as well as the resultant chemistry of these species. Second, she will synthesize potential donors or scavengers of NO and other nitrogen oxides. Third, it’s necessary to describe chemical characterization of these compounds (spectroscopic features, kinetics, mechanisms and profiles of nitrogen oxide release, etc.). Fourth, Dr. Miranda will try to describe the biological characterization of these compounds (assay of effects on biological compounds, mechanisms and pathways, in vitro determination of potential for therapeutic utility, etc.). Fifth, she will identify of potential targets, such as enzymes, for treatment of disease through exposure to nitrogen oxide donors. Keywords: cancer treatment, pain treatment

Publications

Boitano, S., Omsland, A., Miranda, K. M., Friedman, R. L., & Boitano, S. A. (2008). Bordetella bronchiseptica responses to physiological reactive nitrogen and oxygen stresses. FEMS microbiology letters, 284(1).
BIO5 Collaborators
Scott A Boitano, Katrina M Miranda

Bordetella bronchiseptica can establish prolonged airway infection consistent with a highly developed ability to evade mammalian host immune responses. Upon initial interaction with the host upper respiratory tract mucosa, B. bronchiseptica are subjected to antimicrobial reactive nitrogen species (RNS) and reactive oxygen species (ROS), effector molecules of the innate immune system. However, the responses of B. bronchiseptica to redox species at physiologically relevant concentrations (nM-microM) have not been investigated. Using predicted physiological concentrations of nitric oxide (NO), superoxide and hydrogen peroxide (H2O2) on low numbers of CFU of B. bronchiseptica, all redox active species displayed dose-dependent antimicrobial activity. Susceptibility to individual redox active species was significantly increased upon introduction of a second species at subantimicrobial concentrations. An increased bacteriostatic activity of NO was observed relative to H2O2. The understanding of Bordetella responses to physiologically relevant levels of exogenous RNS and ROS will aid in defining the role of endogenous production of these molecules in host innate immunity against Bordetella and other respiratory pathogens.

Jourd'heuil, D., Lancaster Jr., J. R., Fukuto, J., Roberts, D. D., Miranda, K. M., Mayer, B., Grisham, M. B., & Wink, D. A. (2010). The bell-shaped curve for peroxynitrite-mediated oxidation and nitration of NO/O2.- is alive and well. Journal of Biological Chemistry, 285(35), le15.

PMID: 20729216;PMCID: PMC2930750;

Andrei, D., Salmon, D. J., Donzelli, S., Wahab, A., Klose, J. R., Citro, M. L., Saavedra, J. E., Wink, D. A., Miranda, K. M., & Keefer, L. K. (2010). Dual mechanisms of HNO generation by a nitroxyl prodrug of the diazeniumdiolate (NONOate) class. Journal of the American Chemical Society, 132(46), 16526-16532.

PMID: 21033665;PMCID: PMC2984372;Abstract:

Here we describe a novel caged form of the highly reactive bioeffector molecule, nitroxyl (HNO). Reacting the labile nitric oxide (NO)- and HNO-generating salt of structure iPrHN-N(O)=NO-Na+ (1, IPA/NO) with BrCH2OAc produced a stable derivative of structure iPrHN-N(O)=NO-CH2OAc (2, AcOM-IPA/NO), which hydrolyzed an order of magnitude more slowly than 1 at pH 7.4 and 37 °C. Hydrolysis of 2 to generate HNO proceeded by at least two mechanisms. In the presence of esterase, straightforward dissociation to acetate, formaldehyde, and 1 was the dominant path. In the absence of enzyme, free 1 was not observed as an intermediate and the ratio of NO to HNO among the products approached zero. To account for this surprising result, we propose a mechanism in which base-induced removal of the N-H proton of 2 leads to acetyl group migration from oxygen to the neighboring nitrogen, followed by cleavage of the resulting rearrangement product to isopropanediazoate ion and the known HNO precursor, CH3-C(O)-NO. The trappable yield of HNO from 2 was significantly enhanced over 1 at physiological pH, in part because the slower rate of hydrolysis for 2 generated a correspondingly lower steady-state concentration of HNO, thus, minimizing self-consumption and enhancing trapping by biological targets such as metmyoglobin and glutathione. Consistent with the chemical trapping efficiency data, micromolar concentrations of prodrug 2 displayed significantly more potent sarcomere shortening effects relative to 1 on ventricular myocytes isolated from wild-type mouse hearts, suggesting that 2 may be a promising lead compound for the development of heart failure therapies. © 2010 American Chemical Society.

Ford, P., Pereira, J., & Miranda, K. (2013). Mechanisms of nitric oxide reactions mediated by biologically relevant metal centers. Structure and Bonding: Special Issue on Nitrosyl Complexes in Inorganic Chemistry, Biochemistry and Medicine.
Katori, T., Donzelli, S., Tocchetti, C. G., Miranda, K. M., Cormaci, G., Thomas, D. D., Ketner, E. A., Lee, M. J., Mancardi, D., Wink, D. A., Kass, D. A., & Paolocci, N. (2006). Peroxynitrite and myocardial contractility: In vivo versus in vitro effects. Free Radical Biology and Medicine, 41(10), 1606-1618.

PMID: 17045928;Abstract:

Generation of peroxynitrite (ONOO-) as a result of altered redox balance has been shown to affect cardiac function; however, inconsistencies in the data exist, particularly for myocardial contractility. The hypothesis that the cardiac impact of ONOO- formation depends on its site of generation, intravascular or intramyocardial, was examined. Cardiac contractility was assessed by pressure-volume analysis to delineate vascular versus cardiac changes on direct infusion of ONOO- into the right atria of conscious dogs both with normal cardiac function and in heart failure. Additionally, ONOO- was administered to isolated murine cardiomyocytes to mimic in situ cardiac generation. When infused in vivo, ONOO- had little impact on inotropy but led to systemic arterial dilation, likely as a result of rapid decomposition to NO2- and NO3-. In contrast, infused ONOO- was long lived enough to abolish β-adrenergic (dobutamine)-stimulated contractility/relaxation, most likely through catecholamine oxidation to aminochrome. When administered to isolated murine cardiomyocytes, ONOO- induced a rapid reduction in sarcomere shortening and whole cell calcium transients, although neither decomposed ONOO- or NaNO2 had any effect. Thus, systemic generation of ONOO- is unlikely to have primary cardiac effects, but may modulate cardiac contractile reserve, via blunted β-adrenergic stimulation, and vascular tone, as a result of generation of NO2- and NO3-. However, myocyte generation of ONOO- may impair contractile function by directly altering Ca2+ handling. These data demonstrate that the site of generation within the cardiovascular system largely dictates the ability of ONOO- to directly or indirectly modulate cardiac pump function. © 2006 Elsevier Inc. All rights reserved.