Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Diabetes macro- and microvascular disease causes tissue hypoperfusion. This deficit, together with a failure to mount an adequate angiogenic response, might explain why vascular occlusion evolves more severely among diabetic patients. The present study investigated whether prophylactic gene therapy with human tissue kallikrein (hTK) may protect diabetic limbs from the consequences of supervening ischemia. Vehicle (saline) or an adenovirus carrying the gene for either hTK (Ad.hTK) or luciferase (Ad.Luc) was injected into left adductor muscles of streptozotocin-induced type 1 diabetic mice 2 weeks before operative occlusion of the ipsilateral femoral artery. Saline-injected nondiabetic mice served as controls. Hindlimb blood flow recovery was analyzed sequentially over the 2 weeks after ischemia induction. At necroscopy, microvessel density and endothelial cell proliferation and apoptosis were quantified in skeletal muscles. We found that limb perfusion recovery of saline-injected type 1 diabetic mice is delayed because of insufficient reparative neovascularization and excessive activation of endothelial cell apoptosis. By contrast, prophylactic Ad.hTK renewed the ability to mount an appropriate neovascularization response to ischemia, suppressed apoptosis, and upregulated endothelial nitric oxide synthase expression. Ultimately, correction of diabetic endotheliopathy by Ad.hTK allowed proper perfusion recovery as seen in nondiabetic mice. These discoveries disclose new therapeutic options for the treatment of diabetic complications.
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PMID:Prophylactic gene therapy with human tissue kallikrein ameliorates limb ischemia recovery in type 1 diabetic mice. 1504 27

Angiogenesis is essential for the repair of wounds and tissues damaged by ischemia. The regenerative process is tightly regulated by master angiogenic factors, cytokines and the downstream mediator NO. In addition, modulators of vascular growth, such as COX-2-generated prostanoids, contribute to the process by stabilizing the hypoxia-inducible factor and stimulating the expression of VEGF. Recently, we discovered that human tissue kallikrein, a member of the serine proteinase superfamily, possesses potent angiogenic effects. It has been categorized as a pleiotropic angiogenic agent acting via enzymatic cleavage of kininogen and subsequent release of kinin peptides. Kinins bind G-protein coupled receptors, subtype B1 and B2, and exert proliferative effects on endothelial cells via an IP3K-Akt-NO mediated mechanism independent of VEGF. In addition, kinins stimulate the release of angiogenic prostacyclin. Gene transfer of human tissue kallikrein rescues ischemic tissues in otherwise normal mice, as well as in hypertensive or diabetic animals. In addition, prophylactic gene delivery of tissue kallikrein to diabetic skeletal muscles prevents the development of microangiopathy and stimulates collateralization, thus protecting from the consequences of supervening arterial occlusion.
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PMID:Angiogenesis therapy with human tissue kallikrein for the treatment of ischemic diseases. 1528 43

Our previous study has shown that human tissue kallikrein protected against ischemia/reperfusion-induced myocardial injury. In the present study, we investigated the protective role of local kallikrein gene delivery in ischemia/reperfusion-induced cardiomyocyte apoptosis and its signaling mechanisms in promoting cardiomyocyte survival. Adenovirus carrying the human tissue kallikrein gene was delivered locally into the heart using a catheter-based technique. Expression and localization of recombinant human kallikrein in rat myocardium after gene transfer were determined immunohistochemically. Kallikrein gene delivery markedly reduced reperfusion-induced cardiomyocyte apoptosis identified by both in situ nick end-labeling and DNA fragmentation. Delivery of the kallikrein gene increased phosphorylation of Src, Akt, glycogen synthase kinase (GSK)-3beta, and Bad(Ser-136) but reduced caspase-3 activation in rat myocardium after reperfusion. The protective effect of kallikrein on apoptosis and its signaling mediators was blocked by icatibant and dominant-negative Akt, indicating a kinin B2 receptor-Akt-mediated event. Similarly, kinin or transduction of kallikrein in cultured cardiomyocytes promoted cell viability and attenuated apoptosis induced by hypoxia/reoxygenation. The effect of kallikrein on cardiomyocyte survival was blocked by dominant-negative Akt and a constitutively active mutant of GSK-3beta, but it was facilitated by constitutively active Akt, catalytically inactive GSK-3beta, lithium, and caspase-3 inhibitor. Moreover, kallikrein promoted Bad.14-3-3 complex formation and inhibited Akt-GSK-3beta-dependent activation of caspase-3, whereas caspase-3 administration caused reduction of the Bad.14-3-3 complex, indicating an interaction between Akt-GSK-caspase-3 and Akt-Bad.14-3-3 signaling pathways. In conclusion, kallikrein/kinin protects against cardiomyocyte apoptosis in vivo and in vitro via Akt-Bad.14-3-3 and Akt-GSK-3beta-caspase-3 signaling pathways.
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PMID:Kallikrein/kinin protects against myocardial apoptosis after ischemia/reperfusion via Akt-glycogen synthase kinase-3 and Akt-Bad.14-3-3 signaling pathways. 1561 Nov 41

Tissue kallikrein is a serine proteinase capable of cleaving kininogen substrate to produce the potent vasodilator kinin peptide. Kinin mediates a complex set of physiological actions through its receptor signaling. Systemic delivery of the kallikrein gene in an adenoviral vector significantly reduced stroke-induced mortality rate, blood pressure elevation, and aortic hypertrophy in hypertensive Dahl-salt sensitive rats fed a high salt diet. Using a focal cerebral ischemic rat model induced by middle cerebral artery occlusion, intravenous or intracerebroventricular kallikrein gene delivery significantly reduced ischemia/repefusion (I/R)-induced neurological deficits, cerebral infarction, neuronal and glial cell apoptosis, and inflammatory cell infiltration, while promoting angiogenesis and neurogenesis in the ischemic brain. A continuous infusion of a sub-depressor dose of tissue kallikrein protein through implanted minipump decreased I/R-induced neurological dysfunction and cerebral infarction, inflammation and oxidative stress independent of kallikrein's blood pressure-lowering effect. Moreover, kallikrein offered neuroprotection even when delivered at one day after the onset of stroke. Kallikrein's protective effects were blocked by the kinin B2 receptor antagonist icatibant. The role of the kinin B2 receptor in mediating the protective effect against ischemic brain injury was further confirmed by increases in mortality rate and post-ischemic brain injury in kinin B2 receptor-deficient mice. Taken together, these results suggest a novel function of kallikrein as an anti-inflammatory and anti-oxidative agent in protecting the brain against ischemic stroke-induced injuries. These findings also raise the possibility that tissue kallikrein may have value in the treatment of acute ischemic stroke.
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PMID:Experimental therapy with tissue kallikrein against cerebral ischemia. 1636 19

Stroke-induced neurological deficits and mortality are often associated with timing of treatment after the onset of stroke. We showed that local delivery of the human tissue kallikrein gene into rat brain immediately after middle cerebral artery occlusion (MCAO) exerts neuroprotection. In this study, we investigated the effect of systemic delivery of the kallikrein gene 8 hr after MCAO. Expression of recombinant human tissue kallikrein after gene transfer was identified in the ischemic brain region and blood vessels. Intravenous injection of adenovirus encoding the kallikrein gene significantly reduced neurological deficit scores 2 and 7 days after gene transfer. Kallikrein gene transfer also reduced ischemia-reperfusion (I/R)-induced cerebral infarction and promoted the survival and migration of glial cells from penumbra to the ischemic core from 3 to 14 days after gene delivery. Kallikrein reduced I/R-induced apoptosis of neuronal cells and inhibited inflammatory cell accumulation in the ischemic brain. These effects were blocked by the kinin B2 receptor antagonist icatibant. In addition, kallikrein enhanced angiogenesis and promoted neurogenesis after I/R and the stimulatory effect of kinin on neuronal cell proliferation was confirmed in primary cultured neuronal cells. The protective effects of kallikrein, through the kinin B2 receptor, were accompanied by increased cerebral nitric oxide and Bcl-2 levels, Akt phosphorylation, and reduced NAD(P)H oxidase activity, superoxide production, Bax levels, and caspase-3 activity. These results indicate that delayed systemic administration of the kallikrein gene after onset of stroke protects against ischemic brain injury by inhibiting apoptosis and inflammation and by promoting angiogenesis and neurogenesis.
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PMID:Kallikrein protects against ischemic stroke by inhibiting apoptosis and inflammation and promoting angiogenesis and neurogenesis. 1645 54

The kallikrein/kinin system is beneficial in ischemia/reperfusion injury in heart, controversial in brain, but detrimental in lung, liver, and intestine. We examined the role of the kallikrein/kinin system in acute ischemia/reperfusion renal injury induced by 40 min occlusion of the renal artery followed by reperfusion. Rats were infused with tissue kallikrein protein 5 days before (pretreated group) or after (treated group) ischemia. Two days later, the pretreated group exhibited the worst renal dysfunction, followed by the treated group, then the control group. Kallikrein increased tubular necrosis and inflammatory cell infiltration with generation of more tumor necrosis factor-alpha and monocyte chemoattractant protein-1. Reactive oxygen species (ROS), malondialdehyde, and reduced/oxidized glutathione measurement revealed that the oxidative stress was augmented by kallikrein administration in both ischemic and reperfusion phases. The groups with more ROS generation also had more apoptotic renal cells. The deleterious effects of kallikrein on ischemia/reperfusion injury were reversed by cotreatment with bradykinin B2 receptor (B2R) antagonist, but not B1 receptor antagonist, and were not associated with hemodynamic changes. We conclude that early activation of B2R augmented ROS generation in ischemia/reperfusion renal injury, resulting in subsequent apoptosis, inflammation, and tissue damage. This finding suggests the potential application of B2R antagonists in acute ischemic renal disease associated with bradykinin activation.
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PMID:Early activation of bradykinin B2 receptor aggravates reactive oxygen species generation and renal damage in ischemia/reperfusion injury. 1701 77

Bradykinin coronary outflow, left ventricular performance and left ventricular dimensions of transgenic rats harboring the human tissue kallikrein-1 gene TGR(hKLK1) were investigated under basal and ischemic conditions. Bradykinin content in the coronary outflow of buffer-perfused, isolated hearts of controls and TGR(hKLK1) was measured by specific radioimmunoassay before and after global ischemia. Left ventricular function and left ventricular dimensions were determined in vivo using a tip catheter and echocardiography 6 days and 3 weeks after induction of myocardial infarction. Left ventricular type I collagen mRNA expression was analyzed by RNase protection assay. Compared to controls, basal bradykinin outflow was 3.5 fold increased in TGR(hKLK1). Ischemia induced an increase of bradykinin coronary outflow in controls but did not induce a further increase in TGR(hKLK1). However, despite similar unchanged infarction sizes, left ventricular function and remodeling improved in TGR(hKLK1) after myocardial infarction, indicated by an increase in left ventricular pressure (+34%; P<0.05), contractility (dp/dt max. +25%; P<0.05), and in ejection fraction (+20%; P<0.05) as well as by a reduction in left ventricular enddiastolic pressure (-49%, P<0.05), left ventricular enddiastolic diameter (-20%, P<0.05), and collagen mRNA expression (-15%, P<0.05) compared to controls. A chronically activated transgenic kallikrein kinin system with expression of human kallikrein-1 gene counteracts the progression of left ventricular contractile dysfunction after experimental myocardial infarction. Further studies have to show whether these results can be caused by other therapeutically options. Long acting bradykinin receptor agonists might be an alternative option to improve ischemic heart disease.
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PMID:Cardiac function and remodeling is attenuated in transgenic rats expressing the human kallikrein-1 gene after myocardial infarction. 1702 64

Diabetes mellitus is associated with macro- and micro-angiopathy, leading to increased risk of peripheral ischemia. In the present study, we have characterized the microvascular phenotype at the level of limb muscles and the spontaneous angiogenesis response to surgically-induced unilateral limb ischemia in a murine model of type-2 diabetes, the obese C57BL/KsOlaHsd-Lepr(db/db) mice (Lepr(db/db)), and in non-diabetic heterozygous Lepr(db/+). Wild type C57BL mice (WT) were used as controls. The basal microvascular phenotype was determined in mice aged 3 or 5 months, while the response to limb ischemia was studied only in 5-month old mice. Moreover, in 5-month old ischemic Lepr(db/db) and Lepr(db/+), we have tested the therapeutic potential of local angiogenesis gene therapy with human tissue kallikrein (hTK) or constitutively-activated Akt kinase (Myr-Akt). We found that in the muscles of 3- or 5-month old Lepr(db/db), apoptosis of endothelial cells was enhanced and the densities of capillary and arteriole were reduced. Arterioles of Lepr(db/db) showed hypertrophic remodelling and, occasionally, lumen occlusion. Following ischemia, Lepr(db/db) showed a defective reparative angiogenesis in ischemic muscle, delayed blood flow recovery, and worsened clinical outcome as compared with controls. Five-month old Lepr(db/+) displayed an increase in endothelial cell apoptosis under basal conditions, while capillary and arteriole densities were normal. Lepr(db/+) mounted a proper reparative angiogenesis response to limb ischemia and regained blood flow to the ischemic limb, regularly. Local gene therapy with hTK or Myr-Akt induced angiogenesis in ischemic muscles of Lepr(db/+) and Lepr(db/db). However, in the Lepr(db/db) neither gene therapy approach improved the blood flow recovery and the clinical outcome from ischemia. In contrast, either hTK or Myr-Akt gene transfer improved the post-ischemic recovery of Lepr(db/+). Type-2 diabetes has a negative impact on the basal microvascular phenotype and severely impairs post-ischemic recovery of limb muscles. Gene therapy-induced stimulation of neovascularization might not suffice as a sole therapeutic strategy to combat type-2 diabetes-related vascular complications. In type-2 diabetic patients, therapeutic angiogenesis may need to be further optimized before being recommended for clinical applications.
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PMID:Type-2 diabetic Lepr(db/db) mice show a defective microvascular phenotype under basal conditions and an impaired response to angiogenesis gene therapy in the setting of limb ischemia. 1712 38

We assessed the role of nitric oxide (NO) and the kinin B2 receptor in mediating tissue kallikrein's actions in intramyocardial inflammation and cardiac remodeling after ischemia/reperfusion (I/R) injury. Adenovirus carrying the human tissue kallikrein gene was delivered locally into rat hearts 4 days prior to 30-minute ischemia followed by 24-hour or 7-day reperfusion with or without administration of icatibant, a kinin B2 receptor antagonist, or N(omega)-nitro-L-arginine methyl ester (L-NAME), a nitric oxide synthase inhibitor. Kallikrein gene delivery improved cardiac contractility and diastolic function, reduced infarct size at 1 day after I/R without affecting mean arterial pressure. Kallikrein treatment reduced macrophage/monocyte and neutrophil accumulation in the infarcted myocardium in association with reduced intercellular adhesion molecule-1 levels. Kallikrein increased cardiac endothelial nitric oxide synthase phosphorylation and NO levels and decreased superoxide formation, TGF-beta1 levels and Smad2 phosphorylation. Furthermore, kallikrein reduced I/R-induced JNK, p38MAPK, IkappaB-alpha phosphorylation and nuclear NF-kappaB activation. In addition, kallikrein improved cardiac performance, reduced infarct size and prevented ventricular wall thinning at 7 days after I/R. The effects of kallikrein on cardiac function, inflammation and signaling mediators were all blocked by icatibant and L-NAME. These results indicate that tissue kallikrein through kinin B2 receptor and NO formation improves cardiac function, prevents inflammation and limits left ventricular remodeling after myocardial I/R by suppression of oxidative stress, TGF-beta1/Smad2 and JNK/p38MAPK signaling pathways and NF-kappaB activation.
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PMID:Nitric oxide mediates cardiac protection of tissue kallikrein by reducing inflammation and ventricular remodeling after myocardial ischemia/reperfusion. 1806 96

Mesenchymal stem cells (MSCs) migrate to sites of tissue injury and serve as an ideal vehicle for cellular gene transfer. As tissue kallikrein has pleiotropic effects in protection against oxidative organ damage, we investigated the potential of kallikrein-modified MSCs (TK-MSCs) in healing injured kidney after acute ischemia/reperfusion (I/R). TK-MSCs secreted recombinant human kallikrein with elevated vascular endothelial growth factor levels in culture medium, and were more resistant to oxidative stress-induced apoptosis than control MSCs. Expression of human kallikrein was identified in rat glomeruli after I/R injury and systemic TK-MSC injection. Engrafted TK-MSCs exhibited advanced protection against renal injury by reducing blood urea nitrogen, serum creatinine levels, and tubular injury. Six hours after I/R, TK-MSC implantation significantly reduced renal cell apoptosis in association with decreased inducible nitric oxide synthase expression and nitric oxide levels. Forty-eight hours after I/R, TK-MSCs inhibited interstitial neutrophil and monocyte/macrophage infiltration and decreased myeloperoxidase activity, superoxide formation, p38 mitogen-activated protein kinase phosphorylation, and expression of tumor necrosis factor-alpha, monocyte chemoattractant protein-1, and intercellular adhesion molecule-1. In addition, tissue kallikrein and kinin significantly inhibited H2O2-induced apoptosis and increased Akt phosphorylation and cell viability in cultured proximal tubular cells. These results indicate that implantation of kallikrein-modified MSCs in the kidney provides advanced benefits in protection against ischemia-induced kidney injury by suppression of apoptosis and inflammation.
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PMID:Kallikrein-modified mesenchymal stem cell implantation provides enhanced protection against acute ischemic kidney injury by inhibiting apoptosis and inflammation. 1855 97


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