Person: Ichinose, Fumito
Loading...
Email Address
AA Acceptance Date
Birth Date
Research Projects
Organizational Units
Job Title
Last Name
Ichinose
First Name
Fumito
Name
Ichinose, Fumito
15 results
Search Results
Now showing 1 - 10 of 15
Publication An Engineered Enzyme That Targets Circulating Lactate to Alleviate Intracellular NADH:NAD+ Imbalance(Springer Science and Business Media LLC, 2020-01-13) Patgiri, Anupam; Skinner, Owen; Miyazaki, Yusuke; Schleifer, Grigorij; Marutani, Eizo; Shah, Hardik; Sharma, Rohit; Goodman, Russell; To, Tsz-Leung; Bao, Xiaoyan; Ichinose, Fumito; Zapol, Warren; Mootha, VamsiAn elevated intracellular NADH/NAD+ ratio, or “reductive stress,” has been associated with multiple diseases, including disorders of the mitochondrial electron transport chain (ETC). As the intracellular NADH/NAD+ ratio can be in near-equilibrium with the circulating lactate/pyruvate ratio, we hypothesized that reductive stress could be alleviated by oxidizing extracellular lactate into pyruvate. We engineered LOXCAT, a fusion of bacterial lactate oxidase (LOX) and catalase (CAT), which irreversibly converts lactate and oxygen to pyruvate and water. Addition of recombinant LOXCAT to the media of cultured human cells with a defective ETC was able to decrease the extracellular lactate/pyruvate ratio, normalize the intracellular NADH/NAD+ ratio, upregulate glycolytic ATP production, and restore cellular proliferation. In mice, tail-vein injected LOXCAT reduced circulating lactate/pyruvate ratio, blunted a metformin-induced rise in blood lactate/pyruvate, and improved NADH/NAD+ balance in heart and brain. Our study lays the groundwork for a class of injectable therapeutic enzymes that alleviate intracellular redox imbalances by directly targeting circulating redox-coupled metabolites.Publication Inhaled nitric oxide improves transpulmonary blood flow and clinical outcomes after prolonged cardiac arrest: a large animal study(BioMed Central, 2015) Derwall, Matthias; Ebeling, Andreas; Nolte, Kay Wilhelm; Weis, Joachim; Rossaint, Rolf; Ichinose, Fumito; Nix, Christoph; Fries, Michael; Brücken, AnneIntroduction: The probability to achieve a return of spontaneous circulation (ROSC) after cardiac arrest can be improved by optimizing circulation during cardiopulomonary resuscitation using a percutaneous left ventricular assist device (iCPR). Inhaled nitric oxide may facilitate transpulmonary blood flow during iCPR and may therefore improve organ perfusion and outcome. Methods: Ventricular fibrillation was electrically induced in 20 anesthetized male pigs. Animals were left untreated for 10 minutes before iCPR was attempted. Subjects received either 20 ppm of inhaled nitric oxide (iNO, n = 10) or 0 ppm iNO (Control, n = 10), simultaneously started with iCPR until 5 hours following ROSC. Animals were weaned from the respirator and followed up for five days using overall performance categories (OPC) and a spatial memory task. On day six, all animals were anesthetized again, and brains were harvested for neurohistopathologic evaluation. Results: All animals in both groups achieved ROSC. Administration of iNO markedly increased iCPR flow during CPR (iNO: 1.81 ± 0.30 vs Control: 1.64 ± 0.51 L/min, p < 0.001), leading to significantly higher coronary perfusion pressure (CPP) during the 6 minutes of CPR (25 ± 13 vs 16 ± 6 mmHg, p = 0.002). iNO-treated animals showed significantly lower S-100 serum levels thirty minutes post ROSC (0.26 ± 0.09 vs 0.38 ± 0.15 ng/mL, p = 0.048), as well as lower blood glucose levels 120–360 minutes following ROSC. Lower S-100 serum levels were reflected by superior clinical outcome of iNO-treated animals as estimated with OPC (3 ± 2 vs. 5 ± 1, p = 0.036 on days 3 to 5). Three out of ten iNO-treated, but none of the Control animals were able to successfully participate in the spatial memory task. Neurohistopathological examination of vulnerable cerebral structures revealed a trend towards less cerebral lesions in neocortex, archicortex, and striatum in iNO-treated animals compared to Controls. Conclusions: In pigs resuscitated with mechanically-assisted CPR from prolonged cardiac arrest, the administration of 20 ppm iNO during and following iCPR improved transpulmonary blood flow, leading to improved clinical neurological outcomes.Publication Nitric oxide regulates pulmonary vascular smooth muscle cell expression of the inducible cAMP early repressor gene(Elsevier BV, 2011) Steinbicker, Andrea U.; Liu, Heling; Jiramongkolchai, Kim; Malhotra, Rajeev; Choe, Elizabeth Y.; Busch, Cornelius J.; Graveline, Amanda; Kao, Sonya M.; Nagasaka, Yasuko; Ichinose, Fumito; Buys, Emmanuel; Brouckaert, Peter; Zapol, Warren; Bloch, KennethNitric oxide (NO) regulates vascular smooth muscle cell (VSMC) structure and function, in part by activating soluble guanylate cyclase (sGC) to synthesize cGMP. The objective of this study was to further characterize the signaling mechanisms by which NO regulates VSMC gene expression using transcription profiling. DNA microarrays were hybridized with RNA extracted from rat pulmonary artery smooth muscle cells (RPaSMC) exposed to the NO donor compound, S-nitroso-glutathione (GSNO). Many of the genes, whose expression was induced by GSNO, contain a cAMP-response element (CRE), of which one encoded the inducible cAMP early repressor (ICER). sGC and cAMP-dependent protein kinase, but not cGMP-dependent protein kinase, were required for NO-mediated phosphorylation of CRE-binding protein (CREB) and induction of ICER gene expression. Expression of a dominant-negative CREB in RPaSMC prevented the NO-mediated induction of CRE-dependent gene transcription and ICER gene expression. Pre-treatment of RPaSMC with the intracellular calcium (Ca2+) chelator, BAPTA-AM, blocked the induction of ICER gene expression by GSNO. The store-operated Ca2+ channel inhibitors, 2-ABP, and SKF-96365, reduced the GSNO-mediated increase in ICER mRNA levels, while 2-ABP did not inhibit GSNO-induced CREB phosphorylation. Our results suggest that induction of ICER gene expression by NO requires both CREB phosphorylation and Ca2+ signaling. Transcription profiling of RPaSMC exposed to GSNO revealed important roles for sGC, PKA, CREB, and Ca2+ in the regulation of gene expression by NO. The induction of ICER in GSNO-treated RPaSMC highlights a novel cross-talk mechanism between cGMP and cAMP signaling pathways.Publication Inhaled Nitric Oxide Improves Outcomes After Successful Cardiopulmonary Resuscitation in Mice(Ovid Technologies (Wolters Kluwer Health), 2011) Minamishima, Shizuka; Kida, Kotaro; Tokuda, Kentaro; Wang, Huifang; Sips, Patrick; Kosugi, Shizuko; Mandeville, Joseph; Buys, Emmanuel; Brouckaert, Peter; Liu, Philip; Liu, Christina; Bloch, Kenneth; Ichinose, FumitoBackground—Sudden cardiac arrest (CA) is a leading cause of death worldwide. Breathing nitric oxide (NO) reduces ischemia/reperfusion injury in animal models and in patients. The objective of this study was to learn whether inhaled NO improves outcomes after CA and cardiopulmonary resuscitation (CPR). Methods and Results—Adult male mice were subjected to potassium-induced CA for 7.5 minutes whereupon CPR was performed with chest compression and mechanical ventilation. One hour after CPR, mice were extubated and breathed air alone or air supplemented with 40 ppm NO for 23 hours. Mice that were subjected to CA/CPR and breathed air exhibited a poor 10-day survival rate (4 of 13), depressed neurological and left ventricular function, and increased caspase-3 activation and inflammatory cytokine induction in the brain. Magnetic resonance imaging revealed brain regions with marked water diffusion abnormality 24 hours after CA/CPR in mice that breathed air. Breathing air supplemented with NO for 23 hours starting 1 hour after CPR attenuated neurological and left ventricular dysfunction 4 days after CA/CPR and markedly improved 10-day survival rate (11 of 13; P=0.003 versus mice breathing air). The protective effects of inhaled NO on the outcome after CA/CPR were associated with reduced water diffusion abnormality, caspase-3 activation, and cytokine induction in the brain and increased serum nitrate/nitrite levels. Deficiency of the α1 subunit of soluble guanylate cyclase, a primary target of NO, abrogated the ability of inhaled NO to improve outcomes after CA/CPR. Conclusions—These results suggest that NO inhalation after CA and successful CPR improves outcome via soluble guanylate cyclase–dependent mechanisms.Publication NOS3 Protects Against Systemic Inflammation and Myocardial Dysfunction in Murine Polymicrobial Sepsis(Ovid Technologies (Wolters Kluwer Health), 2010) Bougaki, Masahiko; Searles, Robert J.; Kida, Kotaro; Yu, JiaDe; Buys, Emmanuel; Ichinose, FumitoNO has been implicated in the pathogenesis of septic shock. However, the role of NO synthase 3 (NOS3) during sepsis remains incompletely understood. Here, we examined the impact of NOS3 deficiency on systemic inflammation and myocardial dysfunction during peritonitis-induced polymicrobial sepsis. Severe polymicrobial sepsis was induced by colon ascendens stent peritonitis (CASP) in wild-type (WT) and NOS3-deficient (NOS3KO) mice. NOS3KO mice exhibited shorter survival time than did WT mice after CASP. NOS3 deficiency worsened systemic inflammation assessed by the expression of inflammatory cytokines in the lung, liver, and heart. Colon ascendens stent peritonitis markedly increased the number of leukocyte infiltrating the liver and heart in NOS3KO but not in WT mice. The exaggerated systemic inflammation in septic NOS3KO mice was associated with more marked myocardial dysfunction than in WT mice 22 h after CASP. The detrimental effects of NOS3 deficiency on myocardial function after CASP seem to be caused by impaired Ca2+ handling of cardiomyocytes. The impaired Ca2+ handling of cardiomyocytes isolated from NOS3KO mice subjected to CASP was associated with depressed mitochondrial ATP production, a determinant of the Ca2+ cycling capacity of sarcoplasmic reticulum Ca2+-ATPase. The NOS3 deficiency-induced impairment of the ability of mitochondria to produce ATP after CASP was at least in part attributable to reduction in mitochondrial respiratory chain complex I activity. These observations suggest that NOS3 protects against systemic inflammation and myocardial dysfunction after peritonitis-induced polymicrobial sepsis in mice.Publication Protective effects of nitric oxide synthase 3 and soluble guanylate cyclase on the outcome of cardiac arrest and cardiopulmonary resuscitation in mice*(Ovid Technologies (Wolters Kluwer Health), 2009) Nishida, Takefumi; De Yu, Jia; Minamishima, Shizuka; Sips, Patrick; Searles, Robert J.; Buys, Emmanuel; Janssens, Stefan; Brouckaert, Peter; Bloch, Kenneth; Ichinose, FumitoObjectives: Despite advances in resuscitation methods, survival after out-of-hospital cardiac arrest remains low, at least in part, due to postcardiac arrest circulatory and neurologic failure. To elucidate the role of nitric oxide (NO) in the recovery from cardiac arrest and cardiopulmonary resuscitation (CPR), we studied the impact of NO synthase (NOS3)/cGMP signaling on cardiac and neurologic outcomes after cardiac arrest and CPR. Design: Prospective, randomized, controlled study. Setting: Animal research laboratory. Subjects: Mice. Interventions: Female wild-type (WT) mice, NOS3-deficient mice (NOS3−/−), NOS3−/− mice with cardiomyocyte-specific overexpression of NOS3 (NOS3−/−CSTg), and mice deficient for soluble guanylate cyclase α1 (sGCα1−/−) were subjected to potassium-induced cardiac arrest (9 min) followed by CPR. Cardiac and neurologic function and survival were assessed up to 24 hrs post-CPR. Measurements and Main Results: Cardiac arrest and CPR markedly depressed myocardial function in NOS3−/− and sGCα1−/− but not in WT and NOS3−/−CSTg. Neurologic function score and 24 hrs survival rate was lower in NOS3−/− and sGCα1−/− compared with WT and NOS3−/−CSTg. Detrimental effects of deficiency of NOS3 or sGCα1 were associated with enhanced inflammation of heart and liver and increased cell death in heart, liver, and brain that were largely prevented by cardiomyocyte-restricted NOS3 overexpression. Conclusions: These results demonstrate an important salutary impact of NOS3/sGC signaling on the outcome of cardiac arrest. Myocardial NOS3 prevented postcardiac arrest myocardial dysfunction, attenuated end-organ damage, and improved neurologic outcome and survival. Our observations suggest that enhancement of cardiac NOS3 and/or sGC activity may improve outcome after cardiac arrest and CPR.Publication sGCα1 Mediates the Negative Inotropic Effects of NO in Cardiac Myocytes Independent of Changes in Calcium Handling(American Physiological Society, 2011) Cawley, Sharon M.; Kolodziej, Starsha; Ichinose, Fumito; Brouckaert, Peter; Buys, Emmanuel; Bloch, KennethIn the heart, nitric oxide (NO) modulates contractile function; however, the mechanisms responsible for this effect are incompletely understood. NO can elicit effects via a variety of mechanisms including S-nitrosylation and stimulation of cGMP synthesis by soluble guanylate cyclase (sGC). sGC is a heterodimer comprised of a β1- and an α1- or α2-subunit. sGCα1β1 is the predominant isoform in the heart. To characterize the role of sGC in the regulation of cardiac contractile function by NO, we compared left ventricular cardiac myocytes (CM) isolated from adult mice deficient in the sGC α1-subunit (sGCα1−/−) and from wild-type (WT) mice. Sarcomere shortening under basal conditions was less in sGCα1−/− CM than in WT CM. To activate endogenous NO synthesis from NO synthase 3, CM were incubated with the β3-adrenergic receptor (β3-AR) agonist BRL 37344. BRL 37344 decreased cardiac contractility in WT CM but not in sGCα1−/− myocytes. Administration of spermine NONOate, an NO donor compound, did not affect sarcomeric shortening in CM of either genotype; however, in the presence of isoproterenol, addition of spermine NONOate reduced sarcomere shortening in WT but not in sGCα1−/− CM. Neither BRL 37344 nor spermine NONOate altered calcium handling in CM of either genotype. These findings suggest that sGCα1 exerts a positive inotropic effect under basal conditions, as well as mediates the negative inotropic effect of β3-AR signaling. Additionally, our work demonstrates that sGCα1β1 is required for NO to depress β1/β2-AR-stimulated cardiac contractility and that this modulation is independent of changes in calcium handling.Publication Myocardial Alterations in Senescent Mice and Effect of Exercise Training: A Strain Rate Imaging Study(Ovid Technologies (Wolters Kluwer Health), 2008) Derumeaux, G.; Ichinose, Fumito; Raher, M. J.; Morgan, J. G.; Coman, T.; Lee, C.; Cuesta, J. M.; Thibault, H.; Bloch, K. D.; Picard, Michael; Scherrer-Crosbie, MarielleBackground: Aging is accompanied by an alteration in myocardial contractility. However, its noninvasive detection is difficult. The effect of chronic exercise on this decrease is unknown. Murine models of senescence are increasingly used to test therapies in aging. We tested whether strain rate imaging detected left ventricular (LV) systolic dysfunction in aging mice and was able to assess a potential improvement after exercise. Methods and Results: Young (3 weeks), adult (2 to 3 months), and old (6 to 18 months) C57BL6 male mice underwent echocardiograms with strain rate imaging, either in sedentary conditions or before, 2 weeks and 4 weeks after chronic swimming. Hemodynamic parameters of LV function including maximal and end-systolic elastance were obtained before euthanizing. LV fibrosis was measured using Sirius red staining. Conventional echocardiography was unable to detect LV systolic dysfunction in old mice, whereas both systolic strain rate and load-independent hemodynamic parameters such as preload recruitable stroke work and end-systolic elastance were significantly decreased. Both strain rate and load-independent hemodynamic parameters normalized after 4 weeks of exercise. Both endocardial and epicardial fibrosis were increased in the LV of aging mice. Endocardial fibrosis decreased in exercised aged mice. Conclusions: Strain rate noninvasively detects LV systolic dysfunction associated with aging in mice, whereas conventional echocardiography does not. Chronic exercise normalizes LV systolic function and decreases fibrosis in old mice. Strain rate imaging in mice may be a useful tool to monitor the effect of new therapeutic strategies preventing the myocardial dysfunction associated with aging.Publication Sensitivity to Sevoflurane anesthesia is decreased in mice with a congenital deletion of Guanylyl Cyclase-1 alpha(BioMed Central, 2017) Nagasaka, Yasuko; Wepler, Martin; Thoonen, Robrecht; Sips, Patrick Y.; Allen, Kaitlin; Graw, Jan A.; Yao, Vincent; Burns, Sara M.; Muenster, Stefan; Brouckaert, Peter; Miller, Keith; Solt, Ken; Buys, Emmanuel; Ichinose, Fumito; Zapol, WarrenBackground: Volatile anesthetics increase levels of the neurotransmitter nitric oxide (NO) and the secondary messenger molecule cyclic guanosine monophosphate (cGMP) in the brain. NO activates the enzyme guanylyl cyclase (GC) to produce cGMP. We hypothesized that the NO-GC-cGMP pathway contributes to anesthesia-induced unconsciousness. Methods: Sevoflurane-induced loss and return of righting reflex (LORR and RORR, respectively) were studied in wild-type mice (WT) and in mice congenitally deficient in the GC-1α subunit (GC-1−/− mice). Spatial distributions of GC-1α and the GC-2α subunit in the brain were visualized by in situ hybridization. Brain cGMP levels were measured in WT and GC-1−/− mice after inhaling oxygen with or without 1.2% sevoflurane for 20 min. Results: Higher concentrations of sevoflurane were required to induce LORR in GC-1−/− mice than in WT mice (1.5 ± 0.1 vs. 1.1 ± 0.2%, respectively, n = 14 and 14, P < 0.0001). Similarly, RORR occurred at higher concentrations of sevoflurane in GC-1−/− mice than in WT mice (1.0 ± 0.1 vs. 0.8 ± 0.1%, respectively, n = 14 and 14, P < 0.0001). Abundant GC-1α and GC-2α mRNA expression was detected in the cerebral cortex, medial habenula, hippocampus, and cerebellum. Inhaling 1.2% sevoflurane for 20 min increased cGMP levels in the brains of WT mice from 2.6 ± 2.0 to 5.5 ± 3.7 pmol/mg protein (n = 13 and 10, respectively, P = 0.0355) but not in GC-1−/− mice. Conclusion: Congenital deficiency of GC-1α abolished the ability of sevoflurane anesthesia to increase cGMP levels in the whole brain, and increased the concentration of sevoflurane required to induce LORR. Impaired NO-cGMP signaling raises the threshold for producing sevoflurane-induced unconsciousness in mice.Publication Trapping Hydrogen Sulfide (H2S) with Diselenides: The Application in the Design of Fluorescent Probes(American Chemical Society, 2015) Peng, Bo; Zhang, Caihong; Marutani, Eizo; Pacheco, Armando; Chen, Wei; Ichinose, Fumito; Xian, MingHere we report a unique reaction between phenyl diselenide-ester substrates and H2S to form 1,2-benzothiaselenol-3-one. This reaction proceeded rapidly under mild conditions. Thiols could also react with the diselenide substrates. However, the resulted S–Se intermediate retained high reactivity toward H2S and eventually led to the same cyclized product 1,2-benzothiaselenol-3-one. Based on this reaction two fluorescent probes were developed and showed high selectivity and sensitivity for H2S. The presence of thiols was found not to interfere with the detection process.