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Sample records for prenyldiphosphate converting enzymes

  1. Assay for Angiotensin-Converting Enzyme.

    ERIC Educational Resources Information Center

    Russo, Salvatore F.

    1983-01-01

    Describes a three-hour experiment designed to introduce students to chemistry of the angiotensis-converting enzyme, illustrate design of a quenched fluorescence substrate, and examine considerations necessary in designing a clinical assay. Includes background information on the biochemistry of hypertension, reagents/materials needed, procedures…

  2. Angiotensin converting enzymes in fish venom.

    PubMed

    Dos Santos, Dávida Maria Ribeiro Cardoso; de Souza, Cledson Barros; Pereira, Hugo Juarez Vieira

    2017-06-01

    Animal venoms are multifaceted mixtures, including proteins, peptides and enzymes produced by animals in defense, predation and digestion. These molecules have been investigated concerning their molecular mechanisms associated and possible pharmacological applications. Thalassophryne nattereri is a small venomous fish inhabiting the northern and northeastern coast of Brazil, and represents a relatively frequent cause of injuries. Its venom causes severe inflammatory response followed frequently by the necrosis of the affected area. Scorpaena plumieri is the most venomous fish in the Brazilian fauna and is responsible for relatively frequent accidents involving anglers and bathers. In humans, its venom causes edema, erythema, ecchymoses, nausea, vomiting, and syncope. Recently, the presence of a type of angiotensin converting enzyme (ACE) activity in the venom of Thalassophryne nattereri and Scorpaena plumieri, endemic fishes in northeastern coast of Brazil, has been described. The ACE converts angiotensin I (Ang I) into angiotensin II (Ang II) and inactivates bradykinin, there by regulating blood pressure and electrolyte homeostasis, however, their function in these venoms remains an unknown. This article provides an overview of the current knowledge on ACE in the venoms of Thalassophryne nattereri and Scorpaena plumier.

  3. Angiotensin converting enzyme 2 and atherosclerosis.

    PubMed

    Wang, Yutang; Tikellis, Chris; Thomas, Merlin C; Golledge, Jonathan

    2013-01-01

    Angiotensin converting enzyme 2 (ACE2) is a homolog of angiotensin converting enzyme (ACE) which generates angiotensin II from angiotensin I. ACE, its product angiotensin II and the downstream angiotensin type I receptor are important components of the renin-angiotensin system (RAS). Angiotensin II, the most important component of the RAS, promotes the development of atherosclerosis. The identification of ACE2 in 2000 opened a new chapter of research on the regulation of the RAS. ACE2 degrades pro-atherosclerotic angiotensin II and generates anti-atherosclerotic angiotensin 1-7. In this review, we explored the importance of ACE2 in protecting experimental animals from developing atherosclerosis and its involvement in human atherosclerosis. We also examined the published evidence assessing the importance of ACE2 in different cell types relevant to atherosclerosis and putative underlying cellular and molecular mechanisms linking ACE2 with protection from atherosclerosis. ACE2 shifts the balance from angiotensin II to angiotensin 1-7 inhibiting the progression of atherosclerosis in animal models.

  4. [Oxidative inactivation of angiotensin-converting enzyme].

    PubMed

    Sakharov, I Iu; Dukhanina, E A; Puchnina, E A; Danilov, S M; Muzykantov, V R

    1991-01-01

    Hydrogen peroxide inactivates the purified human angiotensin-converting enzyme (ACE) in vitro; the inactivating effect of H2O2 is eliminated by an addition of catalase. The lung and kidney ACE are equally sensitive to the effect of hydrogen peroxide. After addition of oxidants (H2O2 alone or H2O2 + ascorbate or H2O2 + Fe2+ mixtures) to the membranes or homogenates of the lung, the inactivation of membrane-bound ACE is far less pronounced despite the large-scale accumulation of lipid peroxidation products. The marked inactivation of ACE in the membrane fraction (up to 55% of original activity) was observed during ACE incubation with a glucose:glucose oxidase:Fe2+ mixture. Presumably the oxidative potential of H2O2 in tissues in consumed, predominantly, for the oxidation of other components of the membrane (e.g., lipids) rather than for ACE inactivation.

  5. Angiotensin converting enzyme inhibition and the kidney

    NASA Technical Reports Server (NTRS)

    Hollenberg, N. K.

    1988-01-01

    Angiotensin II (Ang II) induces a marked reduction in renal blood flow at doses well below those required to induce a pressor response, and as blood flow falls there is a decline in glomerular filtration rate and sodium excretion. This striking sensitivity of the renal blood supply led many workers to consider the possibility that angiotensin functions as a local renal hormone. As angiotensin converting enzyme (ACE) was found in particular abundance in the lung, it seemed reasonable to suspect that most of the conversion occurred there, and that the function of Ang II would be primarily systemic, rather than intrarenal. In this review, I will explore the evidence that has accumulated on these two possibilities, since they have important implications for our current understanding of normal kidney function and derangements of kidney function in disease.

  6. Angiotensin Converting Enzyme Activity in Alopecia Areata

    PubMed Central

    Namazi, Mohammad Reza; Handjani, Farhad; Eftekhar, Ebrahim; Kalafi, Amir

    2014-01-01

    Background. Alopecia areata (AA) is a chronic inflammatory disease of the hair follicle. The exact pathogenesis of AA remains unknown, although recent studies support a T-cell mediated autoimmune process. On the other hand, some studies have proposed that the renin-angiotensin-aldosterone system (RAAS) may play a role in autoimmunity. Therefore, we assessed serum activity of angiotensin converting enzyme (ACE), a component of this system, in AA. Methods. ACE activity was measured in the sera of 19 patients with AA and 16 healthy control subjects. In addition, the relationship between severity and duration of the disease and ACE activity was evaluated. Results. Serum ACE activity was higher in the patient group (55.81 U/L) compared to the control group (46.41 U/L), but the difference was not statistically significant (P = 0.085). Also, there was no correlation between ACE activity and severity (P = 0.13) and duration of disease (P = 0.25) in the patient group. Conclusion. The increased serum ACE activity found in this study may demonstrate local involvement of the RAAS in the pathogenesis of AA. Assessment of ACE in a study with a larger sample size as well as in tissue samples is recommended in order to further evaluate the possible role of RAAS in AA. PMID:25349723

  7. Angiotensin-Converting Enzymes Play a Dominant Role in Fertility

    PubMed Central

    Pan, Pei-Pei; Zhan, Qi-Tao; Le, Fang; Zheng, Ying-Ming; Jin, Fan

    2013-01-01

    According to the World Health Organization, infertility, associated with metabolic syndrome, has become a global issue with a 10%–20% incidence worldwide. An accumulating body of evidence has shown that the renin–angiotensin system is involved in the fertility problems observed in some populations. Moreover, alterations in the expression of angiotensin-converting enzyme-1, angiotensin-converting enzyme-2, and angiotensin-converting enzyme-3 might be one of the most important mechanisms underlying both female and male infertility. However, as a pseudogene in humans, further studies are needed to explore whether the abnormal angiotensin-converting enzyme-3 gene could result in the problems of human reproduction. In this review, the relationship between angiotensin-converting enzymes and fertile ability is summarized, and a new procedure for the treatment of infertility is discussed. PMID:24152441

  8. Identification of interleukin-8 converting enzyme as cathepsin L.

    PubMed

    Ohashi, Kensaku; Naruto, Masanobu; Nakaki, Toshio; Sano, Emiko

    2003-06-26

    IL-8 is produced by various cells, and the NH(2)-terminal amino acid sequence of IL-8 displays heterogeneity among cell types. The mature form of IL-8 has 72 amino acids (72IL-8), while a precursor form (77IL-8) of IL-8 has five additional amino acids to the 72IL-8 NH(2)-terminal. However, it has been unclear how IL-8 is processed to yield the mature form. In this study, converting enzyme was purified as a single 31-kDa band on silver-stained polyacrylamide gel from 160 l of cultured fibroblast supernatant by sequential chromatography. NH(2)-terminal amino acid sequence analysis revealed a sequence, EAPRSVDWRE, which was identified as a partial sequence of cathepsin L. Polyclonal antibodies raised against cathepsin L recognized the purified converting enzyme on Western blot. Moreover, human hepatic cathepsin L cleaved 77IL-8 between Arg(5) and Ser(6), which is the same cleavage site as the putative converting enzyme, resulting in 72IL-8 formation. These data indicate that the converting enzyme of the partially purified fraction of the human fibroblast culture supernatant was cathepsin L. Furthermore, 72IL-8 was sevenfold more potent than 77IL-8 in a neutrophil chemotaxis assay. These results show that cathepsin L is secreted from human fibroblasts in response to external stimuli and plays an important role in IL-8 processing in inflammatory sites.

  9. The history of inhibitors of angiotensin converting enzyme.

    PubMed

    Vane, J R

    1999-12-01

    This review paper by Sir John Vane, The Nobel Prize Laureate for the first time reveals the insides of discovery of inhibitors of angiotensin converting enzyme (ACE-1), presently known as important drugs for the treatment of hypertension, congestive heart failure and coronary artery disease.

  10. Development of enzymes and enzyme systems by genetic engineering to convert biomass to sugars

    Technology Transfer Automated Retrieval System (TEKTRAN)

    TITLE Development of Enzymes and Enzyme Systems by Genetic Engineering to Convert Biomass to Sugars ABSTRACT Plant cellulosic material is one of the most viable renewable resources for the world’s fuel and chemical feedstock needs. Currently ethanol derived from corn starch is the most common li...

  11. Angiotensin converting enzyme from sheep mammary, lingual and other tissues.

    PubMed

    Rao, N Mallikarjuna; Udupa, E G Padmanabha

    2007-11-01

    Occurrence of angiotensin converting enzyme (ACE) in mammary gland and tongue taste epithelium was demonstrated for the first time. Six times higher ACE activity in lactating mammary gland, than non-lactating mammary gland, suggested pregnancy and lactation hormonal dependent expression of ACE in female mammals. ACE activity was highest in choroid plexus, less in spinal cord and moderate in cerebrum, medulla, cerebellum and pons. Distribution of ACE in different regions of skin, kidney and among other tissues was different. Presence of ACE in adrenal glands, pancreas, bone marrow and thyroid gland indicated functions other than blood pressure homeostasis for this enzyme.

  12. Small Bowel Angioedema Secondary to Angiotensin-Converting Enzyme Inhibitors

    PubMed Central

    Hurairah, Abu

    2016-01-01

    Small bowel angioedema induced by angiotensin-converting enzyme (ACE) inhibitors is a rare clinicopathologic entity. It frequently poses a diagnostic challenge and is often not recognized before surgical exploration. The present study illustrates that clinical awareness for this condition and adequate use of radiologic investigations can help make the correct diagnosis of ACE inhibitor-associated angioedema, thus avoiding the cost and morbidity associated with unnecessary interventions. PMID:28133581

  13. Angiotensin-converting enzyme inhibition by Brazilian plants.

    PubMed

    Braga, Fernão C; Serra, Carla P; Viana, Nilton S; Oliveira, Alaíde B; Côrtes, Steyner F; Lombardi, Júlio A

    2007-07-01

    The potential antihypertensive activity of Brazilian plants was evaluated in vitro by its ability to inhibit the angiotensin-converting enzyme (ACE). Forty-four plants belonging to 30 families were investigated. Plants were selected based on their popular use as antihypertensive and/or diuretics. The following plants presented significant ACE inhibition rates: Calophyllum brasiliense, Combretum fruticosum, Leea rubra, Phoenix roebelinii and Terminalia catappa.

  14. Endothelin-converting enzymes and related metalloproteases in Alzheimer's disease.

    PubMed

    Pacheco-Quinto, Javier; Herdt, Aimee; Eckman, Christopher B; Eckman, Elizabeth A

    2013-01-01

    The efficient clearance of amyloid-β (Aβ) is essential to modulate levels of the peptide in the brain and to prevent it from accumulating in senile plaques, a hallmark of Alzheimer's disease (AD) pathology.We and others have shown that failure in Aβ catabolism can produce elevations in Aβ concentration similar to those observed in familial forms of AD. Based on the available evidence, it remains plausible that in late-onset AD, disturbances in the activity of Aβ degrading enzymes could induce Aβ accumulation, and that this increase could result in AD pathology. The following review presents a historical perspective of the parallel discovery of three vasopeptidases (neprilysin and endothelin-converting enzymes-1 and -2) as important Aβ degrading enzymes. The recognition of the role of these vasopeptidases in Aβ degradation, beyond bringing to light a possible explanation of how cardiovascular risk factors may influence AD risk, highlights a possible risk of the use of inhibitors of these enzymes for other clinical indications such as hypertension. We will discuss in detail the experiments conducted to assess the impact of vasopeptidase deficiency (through pharmacological inhibition or genetic mutation) on Aβ accumulation, as well as the cooperative effect of multiple Aβ degrading enzymes to regulate the concentration of the peptide at multiple sites, both intracellular and extracellular, throughout the brain.

  15. Angiotensin Converting Enzyme Regulates Cell Proliferation and Migration

    PubMed Central

    Carvalho, Clarissa Coelho; Florentino, Rodrigo Machado; França, Andressa; Matias, Eveline; Guimarães, Paola Bianchi; Batista, Carolina; Freire, Valder; Carmona, Adriana Karaoglanovic; Pesquero, João Bosco; de Paula, Ana Maria; Foureaux, Giselle; Leite, Maria de Fatima

    2016-01-01

    Background The angiotensin-I converting enzyme (ACE) plays a central role in the renin-angiotensin system, acting by converting the hormone angiotensin-I to the active peptide angiotensin-II (Ang-II). More recently, ACE was shown to act as a receptor for Ang-II, and its expression level was demonstrated to be higher in melanoma cells compared to their normal counterparts. However, the function that ACE plays as an Ang-II receptor in melanoma cells has not been defined yet. Aim Therefore, our aim was to examine the role of ACE in tumor cell proliferation and migration. Results We found that upon binding to ACE, Ang-II internalizes with a faster onset compared to the binding of Ang-II to its classical AT1 receptor. We also found that the complex Ang-II/ACE translocates to the nucleus, through a clathrin-mediated process, triggering a transient nuclear Ca2+ signal. In silico studies revealed a possible interaction site between ACE and phospholipase C (PLC), and experimental results in CHO cells, demonstrated that the β3 isoform of PLC is the one involved in the Ca2+ signals induced by Ang-II/ACE interaction. Further studies in melanoma cells (TM-5) showed that Ang-II induced cell proliferation through ACE activation, an event that could be inhibited either by ACE inhibitor (Lisinopril) or by the silencing of ACE. In addition, we found that stimulation of ACE by Ang-II caused the melanoma cells to migrate, at least in part due to decreased vinculin expression, a focal adhesion structural protein. Conclusion ACE activation regulates melanoma cell proliferation and migration. PMID:27992423

  16. Angiotensin-Converting-Enzyme Inhibition in Stable Coronary Artery Disease

    PubMed Central

    2008-01-01

    BACKGROUND Angiotensin-converting-enzyme (ACE) inhibitors are effective in reducing the risk of heart failure, myocardial infarction, and death from cardiovascular causes in patients with left ventricular systolic dysfunction or heart failure. ACE inhibitors have also been shown to reduce atherosclerotic complications in patients who have vascular disease without heart failure. METHODS In the Prevention of Events with Angiotensin Converting Enzyme Inhibition (PEACE) Trial, we tested the hypothesis that patients with stable coronary artery disease and normal or slightly reduced left ventricular function derive therapeutic benefit from the addition of ACE inhibitors to modern conventional therapy. The trial was a double-blind, placebo-controlled study in which 8290 patients were randomly assigned to receive either trandolapril at a target dose of 4 mg per day (4158 patients) or matching placebo (4132 patients). RESULTS The mean (±SD) age of the patients was 64±8 years, the mean blood pressure 133±17/78±10 mm Hg, and the mean left ventricular ejection fraction 58±9 percent. The patients received intensive treatment, with 72 percent having previously undergone coronary revascularization and 70 percent receiving lipid-lowering drugs. The incidence of the primary end point — death from cardiovascular causes, myocardial infarction, or coronary revascularization — was 21.9 percent in the trandolapril group, as compared with 22.5 percent in the placebo group (hazard ratio in the trandolapril group, 0.96; 95 percent confidence interval, 0.88 to 1.06; P=0.43) over a median follow-up period of 4.8 years. CONCLUSIONS In patients with stable coronary heart disease and preserved left ventricular function who are receiving “current standard” therapy and in whom the rate of cardiovascular events is lower than in previous trials of ACE inhibitors in patients with vascular disease, there is no evidence that the addition of an ACE inhibitor provides further benefit in

  17. Angioedema Related to Angiotensin-Converting Enzyme Inhibitors

    PubMed Central

    Javaud, Nicolas; Achamlal, Jallal; Reuter, Paul-George; Lapostolle, Frédéric; Lekouara, Akim; Youssef, Mustapha; Hamza, Lilia; Karami, Ahmed; Adnet, Frédéric; Fain, Olivier

    2015-01-01

    Abstract The number of cases of acquired angioedema related to angiotensin converting enzyme inhibitors induced (ACEI-AAE) is on the increase, with a potential concomitant increase in life-threatening attacks of laryngeal edema. Our objective was to determine the main characteristics of ACEI-AAE attacks and, in doing so, the factors associated with likelihood of hospital admission from the emergency department (ED) after a visit for an attack. A prospective, multicenter, observational study (April 2012–December 2014) was conducted in EDs of 4 French hospitals in collaboration with emergency services (SAMU 93) and a reference center for bradykinin-mediated angioedema. For each patient presenting with an attack, emergency physicians collected demographic and clinical presentation data, treatments, and clinical course. They recorded time intervals from symptom onset to ED arrival and to treatment decision, from ED arrival to specific treatment with plasma-derived C1-inhibitor (C1-INH) or icatibant, and from specific treatment to onset of symptom relief. Attacks requiring hospital admission were compared with those not requiring admission. Sixty-two eligible patients with ACEI-AAE (56% men, median age 63 years) were included. Symptom relief occurred significantly earlier in patients receiving specific treatment than in untreated patients (0.5 [0.5–1.0] versus 3.9 [2.5–7.0] hours; P < 0.0001). Even though icatibant was injected more promptly than plasma-derived C1-INH, there, however, was no significant difference in median time to onset of symptom relief between the 2 drugs (0.5 [0.5–1.3] versus 0.5 [0.4–1.0] hours for C1-INH and icatibant, respectively, P = 0.49). Of the 62 patients, 27 (44%) were admitted to hospital from the ED. In multivariate analysis, laryngeal involvement and progressive swelling at ED arrival were independently associated with admission (Odds ratio [95% confidence interval] = 6.2 [1.3–28.2] and 5.9 [1.3–26

  18. Endothelin-converting enzyme 2 differentially regulates opioid receptor activity

    PubMed Central

    Gupta, A; Fujita, W; Gomes, I; Bobeck, E; Devi, L A

    2015-01-01

    BACKGROUND AND PURPOSE Opioid receptor function is modulated by post-activation events such as receptor endocytosis, recycling and/or degradation. While it is generally understood that the peptide ligand gets co-endocytosed with the receptor, relatively few studies have investigated the role of the endocytosed peptide and peptide processing enzymes in regulating receptor function. In this study, we focused on endothelin-converting enzyme 2 (ECE2), a member of the neprilysin family of metallopeptidases that exhibits an acidic pH optimum, localizes to an intracellular compartment and selectively processes neuropeptides including opioid peptides in vitro, and examined its role in modulating μ receptor recycling and resensitization. EXPERIMENTAL APPROACH The effect of ECE2 inhibition on hydrolysis of the endocytosed peptide was examined using thin-layer chromatography and on μ opioid receptor trafficking using either elisa or microscopy. The effect of ECE2 inhibition on receptor signalling was measured using a cAMP assay and, in vivo, on antinociception induced by intrathecally administered opioids by the tail-flick assay. KEY RESULTS The highly selective ECE2 inhibitor, S136492, significantly impaired μ receptor recycling and signalling by only those ligands that are ECE2 substrates and this was seen both in heterologous cells and in cells endogenously co-expressing μ receptors with ECE2. We also found that ECE2 inhibition attenuated antinociception mediated only by opioid peptides that are ECE2 substrates. CONCLUSIONS AND IMPLICATIONS These results suggest that ECE2, by selectively processing endogenous opioid peptides in the endocytic compartment, plays a role in modulating opioid receptor activity. LINKED ARTICLES This article is part of a themed section on Opioids: New Pathways to Functional Selectivity. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2015.172.issue-2 PMID:24990314

  19. Angiotensin-converting enzyme 2 in lung diseases.

    PubMed

    Kuba, Keiji; Imai, Yumiko; Penninger, Josef M

    2006-06-01

    The renin-angiotensin system (RAS) plays a key role in maintaining blood pressure homeostasis, as well as fluid and salt balance. Angiotensin II, a key effector peptide of the system, causes vasoconstriction and exerts multiple biological functions. Angiotensin-converting enzyme (ACE) plays a central role in generating angiotensin II from angiotensin I, and capillary blood vessels in the lung are one of the major sites of ACE expression and angiotensin II production in the human body. The RAS has been implicated in the pathogenesis of pulmonary hypertension and pulmonary fibrosis, both commonly seen in chronic lung diseases such as chronic obstructive lung disease. Recent studies indicate that the RAS also plays a critical role in acute lung diseases, especially acute respiratory distress syndrome (ARDS). ACE2, a close homologue of ACE, functions as a negative regulator of the angiotensin system and was identified as a key receptor for SARS (severe acute respiratory syndrome) coronavirus infections. In the lung, ACE2 protects against acute lung injury in several animal models of ARDS. Thus, the RAS appears to play a critical role in the pathogenesis of acute lung injury. Indeed, increasing ACE2 activity might be a novel approach for the treatment of acute lung failure in several diseases.

  20. Angiotensin-converting enzyme inhibitory activity in Mexican Fresco cheese.

    PubMed

    Torres-Llanez, M J; González-Córdova, A F; Hernandez-Mendoza, A; Garcia, H S; Vallejo-Cordoba, B

    2011-08-01

    The objective of this study was to evaluate if Mexican Fresco cheese manufactured with specific lactic acid bacteria (LAB) presented angiotensin I-converting enzyme inhibitory (ACEI) activity. Water-soluble extracts (3 kDa) obtained from Mexican Fresco cheese prepared with specific LAB (Lactococcus, Lactobacillus, Enterococcus, and mixtures: Lactococcus-Lactobacillus and Lactococcus-Enterococcus) were evaluated for ACEI activity. Specific peptide fractions with high ACEI were analyzed using reverse phase-HPLC coupled to mass spectrometry for determination of amino acid sequence. Cheese containing Enterococcus faecium or a Lactococcus lactis ssp. lactis-Enterococcus faecium mixture showed the largest number of fractions with ACEI activity and the lowest half-maximal inhibitory concentration (IC(50); <10 μg/mL). Various ACEI peptides derived from β-casein [(f(193-205), f(193-207), and f(193-209)] and α(S1)-casein [f(1-15), f(1-22), f(14-23), and f(24-34)] were found. The Mexican Fresco cheese manufactured with specific LAB strains produced peptides with potential antihypertensive activity.

  1. Serum angiotensin converting enzyme activity in chronic beryllium disease.

    PubMed

    Newman, L S; Orton, R; Kreiss, K

    1992-07-01

    Serum angiotensin converting enzyme (SACE) activity is used as a marker of sarcoidosis activity and severity, but in chronic beryllium disease (CBD) the studies of SACE give conflicting results. We examined SACE activity in 23 CBD patients, five patients with beryllium sensitization, and 25 beryllium-exposed control subjects. CBD patients underwent complete clinical evaluation, including physical examination, pulmonary function testing, exercise physiology testing, chest radiography, and bronchoscopy with bronchoalveolar lavage and biopsy. CBD SACE activity was systematically compared with these clinical markers of disease severity. Of CBD patients, 22% had elevated SACE activity. The test did not discriminate CBD patients from those in the beryllium-sensitized or beryllium-exposed groups. However, SACE activity in CBD correlated with the extent of pulmonary granulomatous inflammation as reflected by the symptom of breathlessness, the number of white cells in bronchoalveolar lavage (r = 0.44), the number of lavage lymphocytes (r = 0.58), the lavage lymphocyte percentage (r = 0.55), and the profusion of small opacities on chest radiograph (r = 0.41). The test-retest reliability of the assay was high (r = 0.84), as was the agreement between fresh and -70 degrees C frozen sera (r = 0.93). We conclude that SACE activity levels may reflect the extent of pulmonary granulomatous inflammation in CBD but that the test does not help discriminate disease from nondisease.

  2. Modulation of angiotensin-converting enzyme by nitric oxide

    PubMed Central

    Ackermann, A; Fernández-Alfonso, M S; Sánchez de Rojas, R; Ortega, T; Paul, M; González, C

    1998-01-01

    The aim of the present study was to determine the effect of nitric oxide (NO) on angiotensin-converting enzyme (ACE) activity.A biochemical study was performed in order to analyse the effect of the NO-donors, SIN-1 and diethylamine/NO (DEA/NO), and of an aqueous solution of nitric oxide on the ACE activity in plasma from 3-month old male Sprague-Dawley rats and on ACE purified from rabbit lung. SIN-1 significantly inhibited the activity of both enzymes in a concentration-dependent way between 1 and 100 μM. DEA/NO inhibited the activity of purified ACE from 0.1 μM to 10 μM and plasma ACE, with a lower potency, between 1 and 100 μM. An aqueous solution of NO (100 and 150 μM) also inhibited significantly the activity of both enzymes. Lineweaver-Burk plots indicated an apparent competitive inhibition of Hip-His-Leu hydrolysis by NO-donors.Modulation of ACE activity by NO was also assessed in the rat carotid artery by comparing contractions elicited by angiotensin I (AI) and AII. Concentration-response curves to both peptides were performed in arteries with endothelium in the presence of the guanylyl cyclase inhibitor, ODQ (10 μM), and the inhibitor of NO formation, L-NAME (0.1 mM). NO, which is still released from endothelium in the presence of 10 μM ODQ, elicited a significant inhibition of AI contractions at low concentrations (1 and 5 nM). In the absence of endothelium, 1 μM SIN-1 plus 10 μM ODQ, as well as 10 μM DEA/NO plus 10 μM ODQ induced a significant inhibition on AI-induced contractions at 1 and 5 nM and at 1–100 nM, respectively.In conclusion, we demonstrated that (i) NO and NO-releasing compounds inhibit ACE activity in a concentration-dependent and competitive way and that (ii) NO release from endothelium physiologically reduces conversion of AI to AII. PMID:9641545

  3. Properties of soluble and particulate angiotensin-converting enzymes of rabbit lung, induced macrophage and serum.

    PubMed

    Friedland, J; Silverstein, E

    1983-01-01

    Rabbit serum, lung and corticosteroid-induced macrophage angiotensin-converting enzymes were compared with respect to migration on polyacrylamide-gel electrophoresis, sucrose gradient centrifugation and Km. Cellular particulate enzymes solubilized by nonidet P40 had approximately half the electrophoretic mobility of soluble enzymes and a similar Km (1.2 mM). Trypsin treatment of nonidet P40 solubilized particulate enzyme converted its electrophoretic mobility to that of soluble enzyme, and rendered it non-aggregating in sucrose gradients lacking detergent, similar to soluble enzyme. Approximate molecular weights by sucrose gradient centrifugation were similar for all enzymes (135,000-158,000). The data suggest that lung and macrophage enzymes are similar and that cellular particulate enzyme may be convertible to soluble enzyme.

  4. Regulation of steady-state beta-amyloid levels in the brain by neprilysin and endothelin-converting enzyme but not angiotensin-converting enzyme.

    PubMed

    Eckman, Elizabeth A; Adams, Stephanie K; Troendle, Frederick J; Stodola, Becky A; Kahn, Murad A; Fauq, Abdul H; Xiao, Hong D; Bernstein, Kenneth E; Eckman, Christopher B

    2006-10-13

    The deposition of beta-amyloid in the brain is a pathological hallmark of Alzheimer disease (AD). Normally, the accumulation of beta-amyloid is prevented in part by the activities of several degradative enzymes, including the endothelin-converting enzymes, neprilysin, insulin-degrading enzyme, and plasmin. Recent reports indicate that another metalloprotease, angiotensin-converting enzyme (ACE), can degrade beta-amyloid in vitro and in cellular overexpression experiments. In addition, ACE gene variants are linked to AD risk in several populations. Angiotensin-converting enzyme, neprilysin and endothelin-converting enzyme function as vasopeptidases and are the targets of drugs designed to treat cardiovascular disorders, and ACE inhibitors are commonly prescribed. We investigated the potential physiological role of ACE in regulating endogenous brain beta-amyloid levels for two reasons: first, to determine whether beta-amyloid degradation might be the mechanism by which ACE is associated with AD, and second, to determine whether ACE inhibitor drugs might block beta-amyloid degradation in the brain and potentially increase the risk for AD. We analyzed beta-amyloid accumulation in brains from ACE-deficient mice and in mice treated with ACE inhibitors and found that ACE deficiency did not alter steady-state beta-amyloid concentration. In contrast, beta-amyloid levels are significantly elevated in endothelin-converting enzyme and neprilysin knock-out mice, and inhibitors of these enzymes cause a rapid increase in beta-amyloid concentration in the brain. The results of these studies do not support a physiological role for ACE in the degradation of beta-amyloid in the brain but confirm roles for endothelin-converting enzyme and neprilysin and indicate that reductions in these enzymes result in additive increases in brain amyloid beta-peptide levels.

  5. Enthalpy of captopril-angiotensin I-converting enzyme binding.

    PubMed

    Ortiz-Salmerón, E; Barón, C; García-Fuentes, L

    1998-09-18

    High-sensitivity titration calorimetry is used to measure changes in enthalpy, heat capacity and protonation for the binding of captopril to the angiotensin I-converting enzyme (ACE; EC 3.4.15.1). The affinity of ACE to captopril is high and changes slightly with the pH, because the number of protons linked to binding is low. The determination of the enthalpy change at different pH values suggests that the protonated group in the captopril-ACE complex exhibits a heat protonation of approximately -30 kJ/mol. This value agrees with the protonation of an imidazole group. The residues which may become protonated in the complex could be two histidines existing in two active sites, which are joined to the amino acids coordinated to Zn2+. Calorimetric measurements indicate that captopril binds to two sites in the monomer of ACE, this binding being enthalpically unfavorable and being dominated by a large positive entropy change. Thus, binding is favored by both electrostatic and hydrophobic interactions. The temperature dependence of the free energy of binding deltaG degrees is weak because of the enthalpy-entropy compensation caused by a large heat capacity change, deltaCp =-4.3+/-0.1 kJ/K/mol of monomeric ACE. The strong favorable binding entropy and the negative deltaCp indicate both a large contribution to binding due to hydrophobic effects, which seem to originate from dehydration of the ligand-protein interface, and slight conformational changes in the vicinity of the active sites.

  6. Bradykinin and angiotensin-converting enzyme inhibition in cardioprotection

    PubMed Central

    Jancso, G; Jaberansari, MT; Gasz, B; Szanto, Z; Cserepes, B; Röth, E

    2004-01-01

    OBJECTIVES: To show that angiotensin-converting enzyme (ACE) inhibition potentiates subthreshold ischemic preconditioning (IPC) via the elevation of bradykinin activity, leading to a fully delayed cardioprotective response. METHODS: On day 1 of the experiment, pigs were subjected to sham (group 1, controls) or IPC protocols. In groups 2 and 3, 4×5 min and 2×2 min of IPC, respectively, were elicited by occluding the left anterior descending coronary artery with percutaneous transluminal coronary angioplasty inflatable balloon catheter. Group 4 was subjected to the ACE inhibitor perindoprilate only. In group 5, the pigs were pretreated with perindoprilate (0.06 mg/kg) and then subjected to 2×2 min IPC. In group 6, intracoronary HOE 140 (a selective bradykinin B2 receptor antagonist) was added before the perindoprilateaugmented subthreshold (2×2 min) PC stimulus. On the second day, all animals underwent 40 min left anterior descending coronary artery ligation and 3 h reperfusion, followed by infarct size analysis using triphenyl tetrazolium chloride staining. RESULTS: The rates of infarct size and risk zone were the following in the experimental groups: group 1, 42.8%; group 2,19.5% (P<0.05); group 3, ischemia/reperfusion (I/R) 33.4%; group 4, I/R 18.4% (P<0.05); group 5, I/R 31.2%; and group 6, I/R 36.3%. A significant increase of nuclear factor kappa B activation in groups 2 and 4 was seen. CONCLUSIONS: Results confirm that ACE inhibitors do not give total pharmacological IPC, but they enhance the induction effect of small ischemic insults, which raises the ischemic tolerance of myocardium. It was determined that enhanced bradykinin activity leads to downstream nuclear factor kappa B activation in this model. PMID:19641692

  7. Angiotensin converting enzyme 2 abrogates bleomycin-induced lung injury.

    PubMed

    Rey-Parra, G J; Vadivel, A; Coltan, L; Hall, A; Eaton, F; Schuster, M; Loibner, H; Penninger, J M; Kassiri, Z; Oudit, G Y; Thébaud, B

    2012-06-01

    Despite substantial progress, mortality and morbidity of the acute respiratory distress syndrome (ARDS), a severe form of acute lung injury (ALI), remain unacceptably high. There is no effective treatment for ARDS/ALI. The renin-angiotensin system (RAS) through Angiotensin-converting enzyme (ACE)-generated Angiotensin II contributes to lung injury. ACE2, a recently discovered ACE homologue, acts as a negative regulator of the RAS and counterbalances the function of ACE. We hypothesized that ACE2 prevents Bleomycin (BLM)-induced lung injury. Fourteen to 16-week-old ACE2 knockout mice-male (ACE2(-/y)) and female (ACE2(-/-))-and age-matched wild-type (WT) male mice received intratracheal BLM (1.5U/kg). Male ACE2(-/y) BLM injured mice exhibited poorer exercise capacity, worse lung function and exacerbated lung fibrosis and collagen deposition compared with WT. These changes were associated with increased expression of the profibrotic genes α-smooth muscle actin (α-SMA) and Transforming Growth Factor ß1. Compared with ACE2(-/y) exposed to BLM, ACE2(-/-) exhibited better lung function and architecture and decreased collagen deposition. Treatment with intraperitoneal recombinant human (rh) ACE2 (2 mg/kg) for 21 days improved survival, exercise capacity, and lung function and decreased lung inflammation and fibrosis in male BLM-WT mice. Female BLM WT mice had mild fibrosis and displayed a possible compensatory upregulation of the AT2 receptor. We conclude that ACE2 gene deletion worsens BLM-induced lung injury and more so in males than females. Conversely, ACE2 protects against BLM-induced fibrosis. rhACE2 may have therapeutic potential to attenuate respiratory morbidity in ALI/ARDS.

  8. Hepatocyte Growth Factor Regulates Angiotensin Converting Enzyme Expression*

    PubMed Central

    Day, Regina M.; Thiel, Gerald; Lum, Julie; Chévere, Rubén D.; Yang, Yongzhen; Stevens, Joanne; Sibert, Laura; Fanburg, Barry L.

    2008-01-01

    Hepatocyte growth factor (HGF) is a mitogen, morphogen, and motogen that functions in tissue healing and acts as an anti-fibrotic factor. The mechanism for this is not well understood. Recent studies implicate somatic angiotensin-converting enzyme (ACE) in fibrosis. We examined the effects of HGF on ACE expression in bovine pulmonary artery endothelial cells (BPAEC). Short term treatment of BPAEC with HGF transiently increased both ACE mRNA (3 h) and activity (24 h), as determined by ACE protease assays and reverse transcription-PCR. Incubation of BPAEC with HGF for longer periods suppressed ACE mRNA (6 h) and activity (72 h). In contrast, phorbol ester (PMA) treatment produced sustained increase in ACE mRNA and activity. We examined the short term molecular effects of HGF on ACE using PMA for comparison. HGF and PMA increased transcription from a luciferase reporter with the core ACE promoter, which contains a composite binding site for SP1/3 and Egr-1. Immunocytochemistry and electrophoretic mobility shift assay showed that both HGF and PMA increased Egr-1 binding. HGF also increased SP3 binding, as measured by EMSA. However, HGF and PMA increased the cellular activity of only Egr-1, not SP3, as measured by luciferase reporter assays. Deletion of the Egr-1 site in the reporter construct completely abrogated HGF-induced transcription but only ~50% of PMA-induced activity. Expression of dominant negative Egr-1 and SP3 blocked up-regulation of the ACE promoter by HGF but only reduced up-regulation by PMA. These results show that HGF transiently increases gene transcription of ACE via activation of Egr-1, whereas PMA regulation involves Egr-1 and additional factor(s). PMID:14679188

  9. Angiotensin Converting Enzyme (ACE) Inhibitor Extends Caenorhabditis elegans Life Span.

    PubMed

    Kumar, Sandeep; Dietrich, Nicholas; Kornfeld, Kerry

    2016-02-01

    Animal aging is characterized by progressive, degenerative changes in many organ systems. Because age-related degeneration is a major contributor to disability and death in humans, treatments that delay age-related degeneration are desirable. However, no drugs that delay normal human aging are currently available. To identify drugs that delay age-related degeneration, we used the powerful Caenorhabditis elegans model system to screen for FDA-approved drugs that can extend the adult lifespan of worms. Here we show that captopril extended mean lifespan. Captopril is an angiotensin-converting enzyme (ACE) inhibitor used to treat high blood pressure in humans. To explore the mechanism of captopril, we analyzed the acn-1 gene that encodes the C. elegans homolog of ACE. Reducing the activity of acn-1 extended the mean life span. Furthermore, reducing the activity of acn-1 delayed age-related degenerative changes and increased stress resistance, indicating that acn-1 influences aging. Captopril could not further extend the lifespan of animals with reduced acn-1, suggesting they function in the same pathway; we propose that captopril inhibits acn-1 to extend lifespan. To define the relationship with previously characterized longevity pathways, we analyzed mutant animals. The lifespan extension caused by reducing the activity of acn-1 was additive with caloric restriction and mitochondrial insufficiency, and did not require sir-2.1, hsf-1 or rict-1, suggesting that acn-1 functions by a distinct mechanism. The interactions with the insulin/IGF-1 pathway were complex, since the lifespan extensions caused by captopril and reducing acn-1 activity were additive with daf-2 and age-1 but required daf-16. Captopril treatment and reducing acn-1 activity caused similar effects in a wide range of genetic backgrounds, consistent with the model that they act by the same mechanism. These results identify a new drug and a new gene that can extend the lifespan of worms and suggest new

  10. Alterations in Circulatory and Renal Angiotensin-Converting Enzyme and Angiotensin-Converting Enzyme 2 in Fetal Programmed Hypertension

    PubMed Central

    Shaltout, Hossam A.; Figueroa, Jorge P.; Rose, James C.; Diz, Debra I.; Chappell, Mark C.

    2009-01-01

    Antenatal betamethasone treatment is a widely accepted therapy to accelerate lung development and improve survival in preterm infants. However, there are reports that infants who receive antenatal glucocorticoids exhibit higher systolic blood pressure in their early adolescent years. We have developed an experimental model of programming whereby the offspring of pregnant sheep administered clinically relevant doses of betamethasone exhibit elevated blood pressure. We tested the hypothesis as to whether alterations in angiotensin-converting enzyme (ACE), ACE2, and neprilysin in serum, urine, and proximal tubules are associated with this increase in mean arterial pressure. Male sheep were administered betamethasone (2 doses of 0.17 mg/kg, 24 hours apart) or vehicle at the 80th day of gestation and delivered at term. Sheep were instrumented at adulthood (1.8 years) for direct conscious recording of mean arterial pressure. Serum and urine were collected and proximal tubules isolated from the renal cortex. Betamethasone-treated animals had elevated mean arterial pressure (97±3 versus 83±2 mm Hg; P<0.05) and a 25% increase in serum ACE activity (48.4±7.0 versus 36.0±2.7 fmol/mL per minute) but a 40% reduction in serum ACE2 activity (18.8±1.2 versus 31.4±4.4 fmol/mL per minute). In isolated proximal tubules, ACE2 activity and expression were 50% lower in the treated sheep with no significant change in ACE or neprilysin activities. We conclude that antenatal steroid treatment results in the chronic alteration of ACE and ACE2 in the circulatory and tubular compartments, which may contribute to the higher blood pressure in this model of fetal programming-induced hypertension. PMID:19047579

  11. Role of angiotensin-converting enzyme inhibitor, lisinopril, on spermatozoal functions in rats.

    PubMed

    Saha, L; Garg, S K; Bhargava, V K; Mazumdar, S

    2000-04-01

    Angiotensin-converting enzyme is present in the male reproductive system but its role in the physiology of reproduction is not known. To see the effect of angiotensin-converting enzyme on spermatozoal functions, lisinopril, an angiotensin-converting enzyme inhibitor, was administered orally using two different doses (10 and 20 mg/kg/day) to rats. Both short-term (2 weeks) and long-term (6 weeks) effects of the drug were observed. Lisinopril treatment resulted in a marked decrease in sperm density, sperm motility and zona pellucida penetration. Acrosome reaction by spermatozoa obtained from drug-treated animals was significantly lower when compared with spermatozoa from normal animals.

  12. [Effects of hydroxyl radicals on purified angiotensin I converting enzyme].

    PubMed

    Michel, B; Nirina, L B; Grima, M; Ingert, C; Coquard, C; Barthelmebs, M; Imbs, J L

    1998-08-01

    Somatic angiotensin-converting enzyme (ACE) is a protein which contains two similar domains (N and C), each possessing a functional active site. The relationship between ACE, its natural substrates and oxygen free radicals is starting to be explored. On one hand, superoxide anions production is induced by angiotensin II and on the other hand, activated polynuclear neutrophils, through free radicals generation, alter endothelial ACE activity. In this study, we examined the impact of hydroxyl radicals (.OH) on purified ACE. .OH were produced using a generator: 2,2'-azo-bis 2-amidinopropane (GRH) provided by Lara-Spiral (Fr). GRH (3 mM), in a time-dependent fashion, inhibited ACE activity. When ACE was co-incubated for 4 h with GRH, its activity decreased by 70%. Addition of dimethylthiourea (DMTU: 0.03 to 1 mM) or mannitol + methionine (20/10 mM), two sets of .OH scavengers, produced a dose-dependent protection on ACE activity. To examine whether oxidation of thiol groups in the ACE molecule could be involved in the action of GRH, the effects of thiol reducing agents: mercaptoethanol and dithiotreitol (DTT) were investigated. These compounds produced a dose-dependent and significant protection; with 100% protection at 0.2 and 0.3 mM for mercaptoethanol and at 0.1 mM for DTT. The hydrolysis of two natural and domain-specific substrates were also explored. The hydrolysis of angiotensin I preferentially cleaved by the C domain was significantly (p < 0.01) inhibited by 57, 58 and 69% in contact with 0.3, 1 and 3 mM GRH [in nmol angio II formed/min/nmol of ACE, n = 4; 35.9 +/- 0.6 (control), 15.5 +/- 2.8 (GRH : 0.3 mM), 15.1 +/- 0.5 (1), 10.9 +/- 0.6 (3)]. The hydrolysis of the hemoregulatory peptide (hp), preferential substrate for the N domain was not affected by GRH at 0.3 mM and inhibited by 28% (not significant) by 1 mM GRH [in nmol ph hydrolized/min/nmol ACE, n = 4; 12.6 +/- 1.9 (control), 14.9 (GRH : 0.3 mM), 8.3 +/- 4.0 (1). These results demonstrated that .OH

  13. Structure, evolutionary conservation, and functions of angiotensin- and endothelin-converting enzymes.

    PubMed

    Macours, Nathalie; Poels, Jeroen; Hens, Korneel; Francis, Carmen; Huybrechts, Roger

    2004-01-01

    Angiotensin-converting enzyme, a member of the M2 metalloprotease family, and endothelin-converting enzyme, a member of the M13 family, are key components in the regulation of blood pressure and electrolyte balance in mammals. From this point of view, they serve as important drug targets. Recently, the involvement of these enzymes in the development of Alzheimer's disease was discovered. The existence of homologs of these enzymes in invertebrates indicates that these enzyme systems are highly conserved during evolution. Most invertebrates lack a closed circulatory system, which excludes the need for blood pressure regulators. Therefore, these organisms represent excellent targets for gaining new insights and revealing additional physiological roles of these important enzymes. This chapter reviews the structural and functional aspects of ACE and ECE and will particularly focus on these enzyme homologues in invertebrates.

  14. Angiotensin-converting enzyme in acute myocardial infarction and angina pectoris.

    PubMed

    Rømer, F K; Kornerup, H J

    1981-06-01

    Serum activity of angiotensin-converting enzyme was measured by serial analysis in 19 patients with acute myocardial infarction and in eight patients with angina pectoris. As a rule no changes in enzyme activity occurred during 6 days observations. However, two patients with infarction exhibited a pronounced fall of enzyme activity which could not be related to clinical events. The analysis seems to have no place in the diagnosis and management of patients with myocardial infarction.

  15. Carbamazepine inhibits angiotensin I-converting enzyme, linking it to the pathogenesis of temporal lobe epilepsy

    PubMed Central

    Almeida, S S; Naffah-Mazzacoratti, M G; Guimarães, P B; Wasinski, F; Pereira, F E G; Canzian, M; Centeno, R S; Carrete, H; Yacubian, E M; Carmona, A K; Vieira, R F F; Nakaie, C R; Sabatini, R A; Perosa, S R; Bacurau, R F P; Gouveia, T L F; Gallo, G; Würtele, M; Cavalheiro, E A; Silva, J A; Pesquero, J B; Araujo, R C

    2012-01-01

    We find that a common mutation that increases angiotensin I-converting enzyme activity occurs with higher frequency in male patients suffering from refractory temporal lobe epilepsy. However, in their brains, the activity of the enzyme is downregulated. As an explanation, we surprisingly find that carbamazepine, commonly used to treat epilepsy, is an inhibitor of the enzyme, thus providing a direct link between epilepsy and the renin–angiotensin and kallikrein–kinin systems. PMID:22832858

  16. Primacy of cardiac chymase over angiotensin converting enzyme as an angiotensin-(1-12) metabolizing enzyme

    PubMed Central

    Ahmad, Sarfaraz; Varagic, Jasmina; VonCannon, Jessica L.; Groban, Leanne; Collawn, James F.; Dell'Italia, Louis J.; Ferrario, Carlos M.

    2016-01-01

    We showed previously that rat angiotensin-(1-12) [Ang-(1-12)] is metabolized by chymase and angiotensin converting enzyme (ACE) to generate Angiotensin II (Ang II). Here, we investigated the affinity of cardiac chymase and ACE enzymes for Ang-(1-12) and Angiotensin I (Ang I) substrates. Native plasma membranes (PMs) isolated from heart and lung tissues of adult spontaneously hypertensive rats (SHR) were incubated with radiolabeled 125I-Ang-(1-12) or 125I-Ang I, in the absence or presence of a chymase or ACE inhibitor (chymostatin and lisinopril, respectively). Products were quantitated by HPLC connected to an in-line flow-through gamma detector. The rate of 125I-Ang II formation from 125I-Ang-(1-12) by chymase was significantly higher (heart: 7.0 ± 0.6 fmol/min/mg; lung: 33 ± 1.2 fmol/min/mg, P < 0.001) when compared to 125I-Ang I substrate (heart: 0.8 ± 0.1 fmol/min/mg; lung: 2.1 ± 0.1 fmol/min/mg). Substrate affinity of 125I-Ang-(1-12) for rat cardiac chymase was also confirmed using excess unlabeled Ang-(1-12) or Ang I (0–250 µM). The rate of 125I-Ang II formation was significantly lower using unlabeled Ang-(1-12) compared to unlabeled Ang I substrate. Kinetic data showed that rat chymase has a lower Km (64 ± 6.3 µM vs 142 ± 17 µM), higher Vmax (13.2 ± 1.3 µM/min/mg vs 1.9 ± 0.2 µM/min/mg) and more than 15-fold higher catalytic efficiency (ratio of Vmax/Km) for Ang-(1-12) compared to Ang I substrate, respectively. We also investigated ACE mediated hydrolysis of 125I-Ang-(1-12) and 125I-Ang I in solubilized membrane fractions of the SHR heart and lung. Interestingly, no significant difference in 125I-Ang II formation by ACE was detected using either substrate, 125I-Ang-(1-12) or 125I-Ang I, both in the heart (1.8 ± 0.2 fmol/min/mg and 1.8 ± 0.3 fmol/min/mg, respectively) and in the lungs (239 ± 25 fmol/min/mg and 248 ± 34 fmol/min/mg, respectively). Compared to chymase, ACE-mediated Ang-(1-12) metabolism in the heart was several fold lower

  17. Is there any difference between angiotensin converting enzyme inhibitors and angiotensin receptor blockers for heart failure?

    PubMed

    Rain, Carmen; Rada, Gabriel

    2015-07-06

    Angiotensin receptor blockers are usually considered as equivalent to angiotensin converting enzyme inhibitors for patients with heart failure and low-ejection fraction. Some guidelines even recommend the former as first line treatment given their better adverse effects profile. Searching in Epistemonikos database, which is maintained by screening 30 databases, we identified four systematic reviews including eight pertinent randomized controlled trials. We combined the evidence using meta-analysis and generated a summary of findings following the GRADE approach. We concluded angiotensin receptor blockers and angiotensin converting enzyme inhibitors probably have a similar effect on mortality, and they might be equivalent in reducing hospitalization risk too. Treatment withdrawal due to adverse effects is probably lower with angiotensin receptor blockers than with angiotensin converting enzyme inhibitors.

  18. The evolution of renin-angiotensin blockade: angiotensin-converting enzyme inhibitors as the starting point.

    PubMed

    Sica, Domenic A

    2010-04-01

    The renin-angiotensin system has been a target in the treatment of hypertension for close to three decades. Several medication classes that block specific aspects of this system have emerged as useful therapies, including angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, and, most recently, direct renin inhibitors. There has been a natural history to the development of each of these three drug classes, starting with their use as antihypertensive agents; thereafter, in each case they have been employed as end-organ protective agents. To date, there has been scant evidence to favor angiotensin receptor blockers or direct renin inhibitors over angiotensin-converting enzyme inhibitors in treating hypertension or in affording end-organ protection; thus, angiotensin-converting enzyme inhibitors remain the standard of care when renin-angiotensin system blockade is warranted.

  19. Calmodulin interacts with angiotensin-converting enzyme-2 (ACE2) and inhibits shedding of its ectodomain.

    PubMed

    Lambert, Daniel W; Clarke, Nicola E; Hooper, Nigel M; Turner, Anthony J

    2008-01-23

    Angiotensin-converting enzyme-2 (ACE2) is a regulatory protein of the renin-angiotensin system (RAS) and a receptor for the causative agent of severe-acute respiratory syndrome (SARS), the SARS-coronavirus. We have previously shown that ACE2 can be shed from the cell surface in response to phorbol esters by a process involving TNF-alpha converting enzyme (TACE; ADAM17). In this study, we demonstrate that inhibitors of calmodulin also stimulate shedding of the ACE2 ectodomain, a process at least partially mediated by a metalloproteinase. We also show that calmodulin associates with ACE2 and that this interaction is decreased by calmodulin inhibitors.

  20. Tumor necrosis factor alpha converting enzyme: an encouraging target for various inflammatory disorders.

    PubMed

    Bahia, Malkeet S; Silakari, Om

    2010-05-01

    Tumor necrosis factor alpha is one of the most common pro-inflammatory cytokines responsible for various inflammatory disorders. It plays an important role in the origin and progression of rheumatoid arthritis and also in other autoimmune disease conditions. Some anti-tumor necrosis factor alpha antibodies like Enbrel, Humira and Remicade have been successfully used in these disease conditions as antagonists of tumor necrosis factor alpha. Inhibition of generation of active form of tumor necrosis factor alpha is a promising therapy for various inflammatory disorders. Therefore, the inhibition of an enzyme (tumor necrosis factor alpha converting enzyme), which is responsible for processing inactive form of tumor necrosis factor alpha into its active soluble form, is an encouraging target. Many tumor necrosis factor alpha converting enzyme inhibitors have been the candidates of clinical trials but none of them have reached in to the market because of their broad spectrum inhibitory activity for other matrix metalloproteases. Selectivity of tumor necrosis factor alpha converting enzyme inhibition over matrix metalloproteases is of utmost importance. If selectivity is achieved successfully, side-effects can be over-ruled and this approach may become a novel therapy for treatment of rheumatoid arthritis and other inflammatory disorders. This cytokine not only plays a pivotal role in inflammatory conditions but also in some cancerous conditions. Thus, successful targeting of tumor necrosis factor alpha converting enzyme may result in multifunctional therapy.

  1. 21 CFR 862.1090 - Angiotensin converting enzyme (A.C.E.) test system.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Angiotensin converting enzyme (A.C.E.) test system. 862.1090 Section 862.1090 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical...

  2. 21 CFR 862.1090 - Angiotensin converting enzyme (A.C.E.) test system.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Angiotensin converting enzyme (A.C.E.) test system. 862.1090 Section 862.1090 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical...

  3. 21 CFR 862.1090 - Angiotensin converting enzyme (A.C.E.) test system.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Angiotensin converting enzyme (A.C.E.) test system. 862.1090 Section 862.1090 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical...

  4. 21 CFR 862.1090 - Angiotensin converting enzyme (A.C.E.) test system.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Angiotensin converting enzyme (A.C.E.) test system. 862.1090 Section 862.1090 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical...

  5. 21 CFR 862.1090 - Angiotensin converting enzyme (A.C.E.) test system.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Angiotensin converting enzyme (A.C.E.) test system. 862.1090 Section 862.1090 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical...

  6. Assessment of 105 Patients with Angiotensin Converting Enzyme-Inhibitor Induced Angioedema

    PubMed Central

    von Buchwald, Christian; Prasad, Sumangali Chandra; Kamaleswaran, Shailajah; Ajgeiy, Kawa Khaled; Authried, Georg; Pallesen, Kristine Appel U.

    2017-01-01

    Objective. To asses a cohort of 105 consecutive patients with angiotensin converting enzyme-inhibitor induced angioedema with regard to demographics, risk factors, family history of angioedema, hospitalization, airway management, outcome, and use of diagnostic codes used for the condition. Study Design. Cohort study. Methods. This was a retrospective cohort study of 105 patients with angiotensin converting enzyme-inhibitor induced angioedema in the period 1995–2014. Results. The cohort consisted of 67 females and 38 males (F : M ratio 1.8), with a mean age of 63 [range 26–86] years. Female gender was associated with a significantly higher risk of angiotensin converting enzyme-inhibitor induced angioedema. 6.7% had a positive family history of angioedema. Diabetes seemed to be a protective factor with regard to angioedema. 95% experienced angioedema of the head and neck. 4.7% needed intubation or tracheostomy. 74 admissions took place during the study period with a total of 143 days spent in the hospital. The diagnosis codes most often used for this condition were “DT783 Quincke's oedema” and “DT78.4 Allergy unspecified”. Complement C1 inhibitor was normal in all tested patients. Conclusion. Female gender predisposes to angiotensin converting enzyme-inhibitor induced angioedema, whereas diabetes seems to be a protective factor. PMID:28286522

  7. Angiotensin-converting enzyme genetic polymorphism: its impact on cardiac remodeling

    PubMed Central

    de Albuquerque, Felipe Neves; Brandão, Andréa Araujo; da Silva, Dayse Aparecida; Mourilhe-Rocha, Ricardo; Duque, Gustavo Salgado; Gondar, Alyne Freitas Pereira; Neves, Luiza Maceira de Almeida; Bittencourt, Marcelo Imbroinise; Pozzan, Roberto; de Albuquerque, Denilson Campos

    2014-01-01

    Background The role of angiotensin-converting enzyme genetic polymorphisms as a predictor of echocardiographic outcomes on heart failure is yet to be established. The local profile should be identified so that the impact of those genotypes on the Brazilian population could be identified. This is the first study on exclusively non-ischemic heart failure over a follow-up longer than 5 years. Objective To determine the distribution of angiotensin-converting enzyme genetic polymorphism variants and their relation with echocardiographic outcome of patients with non-ischemic heart failure. Methods Secondary analysis of the medical records of 111 patients and identification of the angiotensin-converting enzyme genetic polymorphism variants, classified as DD (Deletion/Deletion), DI (Deletion/Insertion) or II (Insertion/Insertion). Results The cohort means were as follows: follow-up, 64.9 months; age, 59.5 years; male sex, 60.4%; white skin color, 51.4%; use of beta-blockers, 98.2%; and use of angiotensin-converting-enzyme inhibitors or angiotensin receptor blocker, 89.2%. The angiotensin-converting enzyme genetic polymorphism distribution was as follows: DD, 51.4%; DI, 44.1%; and II, 4.5%. No difference regarding the clinical characteristics or treatment was observed between the groups. The final left ventricular systolic diameter was the only isolated echocardiographic variable that significantly differed between the angiotensin-converting enzyme genetic polymorphisms: 59.2 ± 1.8 for DD versus 52.3 ± 1.9 for DI versus 59.2 ± 5.2 for II (p = 0.029). Considering the evolutionary behavior, all echocardiographic variables (difference between the left ventricular ejection fraction at the last and first consultation; difference between the left ventricular systolic diameter at the last and first consultation; and difference between the left ventricular diastolic diameter at the last and first consultation) differed between the genotypes (p = 0.024; p = 0.002; and p = 0

  8. Possible identity of IL-8 converting enzyme in human fibroblasts as a cysteine protease.

    PubMed

    Ohashi, Kensaku; Sano, Emiko; Nakaki, Toshio; Naruto, Masanobu

    2003-04-01

    A converting activity was characterized in human diploid fibroblasts, which secrete 72IL-8 and 77IL-8 in treatment with IFN-beta and poly I: poly C. 77IL-8 was significantly converted to 72IL-8 by a partially purified fraction of the culture supernatant of human diploid fibroblasts. The converting activity, which was temperature-dependent and optimal at pH 6, was completely inhibited by cysteine protease inhibitors, antipain dihydrochloride and E-64, but not by other types of protease inhibitors. These data clearly show that human diploid fibroblasts are capable of processing IL-8 to produce a mature IL-8 and that the putative converting enzyme appears to be a cysteine protease.

  9. [Applications of nitrile converting enzymes in the production of fine chemicals].

    PubMed

    Zheng, Yuguo; Xue, Yaping; Liu, Zhiqiang; Zheng, Renchao; Shen, Yinchu

    2009-12-01

    Nitriles are an important type of synthetic intermediates in the production of fine chemicals because of their easy preparations and versatile transformations. The traditional chemical conversion of nitriles to carboxylic acids and amides is feasible but it requires relatively harsh conditions of heat, acid or alkali. Nitrile converting enzymes (nitrilase, nitrile hydratase and amidase) which are used as biocatalyst for the production of fine chemicals have attracted substantial interest because of their ability to convert readily available nitriles into the corresponding higher value amides or acids under mild conditions with excellent chemo-, regio- and stereo-selectivities. Many nitrile converting enzymes have been explored and widely used for the production of fine chemicals. In this paper, various examples of biocatalytic synthesis of pharmaceuticals and their intermediates, agrochemicals and their intermediates, food and feed additives, and other fine chemicals are presented. In the near future, an increasing number of novel nitrile converting enzymes will be screened and their potential in the production of useful fine chemicals will be further exploited.

  10. Properties and applications of starch-converting enzymes of the alpha-amylase family.

    PubMed

    van der Maarel, Marc J E C; van der Veen, Bart; Uitdehaag, Joost C M; Leemhuis, Hans; Dijkhuizen, L

    2002-03-28

    Starch is a major storage product of many economically important crops such as wheat, rice, maize, tapioca, and potato. A large-scale starch processing industry has emerged in the last century. In the past decades, we have seen a shift from the acid hydrolysis of starch to the use of starch-converting enzymes in the production of maltodextrin, modified starches, or glucose and fructose syrups. Currently, these enzymes comprise about 30% of the world's enzyme production. Besides the use in starch hydrolysis, starch-converting enzymes are also used in a number of other industrial applications, such as laundry and porcelain detergents or as anti-staling agents in baking. A number of these starch-converting enzymes belong to a single family: the alpha-amylase family or family13 glycosyl hydrolases. This group of enzymes share a number of common characteristics such as a (beta/alpha)(8) barrel structure, the hydrolysis or formation of glycosidic bonds in the alpha conformation, and a number of conserved amino acid residues in the active site. As many as 21 different reaction and product specificities are found in this family. Currently, 25 three-dimensional (3D) structures of a few members of the alpha-amylase family have been determined using protein crystallization and X-ray crystallography. These data in combination with site-directed mutagenesis studies have helped to better understand the interactions between the substrate or product molecule and the different amino acids found in and around the active site. This review illustrates the reaction and product diversity found within the alpha-amylase family, the mechanistic principles deduced from structure-function relationship structures, and the use of the enzymes of this family in industrial applications.

  11. Overexpression of angiotensin-converting enzyme in myelomonocytic cells enhances the immune response

    PubMed Central

    Bernstein, Kenneth E.; Khan, Zakir; Giani, Jorge F.; Zhao, Tuantuan; Eriguchi, Masahiro; Bernstein, Ellen A.; Gonzalez-Villalobos, Romer A.; Shen, Xiao Z.

    2016-01-01

    Angiotensin-converting enzyme (ACE) converts angiotensin I to the vasoconstrictor angiotensin II and thereby plays an important role in blood pressure control. However, ACE is relatively non-specific in its substrate specificity and cleaves many other peptides. Recent analysis of mice overexpressing ACE in monocytes, macrophages, and other myelomonocytic cells shows that these animals have a marked increase in resistance to experimental melanoma and to infection by Listeria monocytogenes or methicillin-resistant Staphylococcus aureus (MRSA). Several other measures of immune responsiveness, including antibody production, are enhanced in these animals. These studies complement a variety of studies indicating an important role of ACE in the immune response. PMID:27018193

  12. Rediscovering ACE: Novel insights into the many roles of the angiotensin-converting enzyme

    PubMed Central

    Gonzalez-Villalobos, Romer A.; Shen, Xiao Z.; Bernstein, Ellen A.; Janjulia, Tea; Taylor, Brian; Giani, Jorge F.; Blackwell, Wendell-Lamar B.; Shah, Kandarp H.; Shi, Peng D.; Fuchs, Sebastien; Bernstein, Kenneth E.

    2013-01-01

    Angiotensin converting enzyme (ACE) is best known for the catalytic conversion of angiotensin I to angiotensin II. However, the use of gene-targeting techniques has led to mouse models highlighting many other biochemical properties and actions of this enzyme. This review discusses recent studies examining the functional significance of ACE tissue-specific expression and the presence in ACE of two independent catalytic sites with distinct substrates and biological effects. It is these features which explain why ACE makes important contributions to many different physiological processes including renal development, blood pressure control, inflammation and immunity. PMID:23686164

  13. Nitrile-converting enzymes: an eco-friendly tool for industrial biocatalysis.

    PubMed

    Ramteke, Pramod W; Maurice, Navodita G; Joseph, Babu; Wadher, Bharat J

    2013-01-01

    Nitriles are organic compounds bearing a − C ≡ N group; they are frequently known to occur naturally in both fauna and flora and are also synthesized chemically. They have wide applicability in the fields of medicine, industry, and environmental monitoring. However, the majority of nitrile compounds are considered to be lethal, mutagenic, and carcinogenic in nature and are known to cause potential health problems such as nausea, bronchial irritation, respiratory distress, convulsions, coma, and skeletal deformities in humans. Nitrile-converting enzymes, which are extracted from microorganisms, are commonly termed nitrilases and have drawn the attention of researchers all over the world to combat the toxicity of nitrile compounds. The present review focuses on the utility of nitrile-converting enzymes, sources, classification, structure, properties, and applications, as well as the future perspective on nitrilases.

  14. LinA2, a HCH-converting bacterial enzyme that dehydrohalogenates HBCDs.

    PubMed

    Heeb, Norbert V; Wyss, Simon A; Geueke, Birgit; Fleischmann, Thomas; Kohler, Hans-Peter E; Lienemann, Peter

    2014-07-01

    Hexabromocyclododecanes (HBCDs) and hexachlorocyclohexanes (HCHs) are lipophilic, polyhalogenated hydrocarbons with comparable stereochemistry. Bacterial evolution in HCH-contaminated soils resulted in the development of several Spingomonadaceae which express a series of HCH-converting enzymes. We showed that LinB, a haloalkane dehalogenase from Sphingobium indicum B90A, also transforms various HBCDs besides HCHs. Here we present evidence that LinA2, another dehalogenase from S. indicum also converts certain HBCDs to pentabromocyclododecenes (PBCDEs). Racemic mixtures of α-, β-, γ-HBCDs, a mixture of them, and δ-HBCD, a meso form, were exposed to LinA2. Substantial conversion of (-)β-HBCD was observed, but all other stereoisomers were not transformed significantly. The enantiomeric excess (EE) of β-HBCDs increased up to 60% in 32 h, whereas EE values of α- and γ-HBCDs were not affected. Substrate conversion and product formation were described with second-order kinetic models. One major (P1β) and possibly two minor (P2β, P3β) metabolites were detected. Respective mass spectra showed the characteristic isotope pattern of PBCDEs, the HBr elimination products of HBCDs. Michaelis-Menten parameters KM=0.47 ± 0.07 μM and vmax=0.17 ± 0.01 μmoll(-1)h(-1) were deduced from exposure data with varying enzyme/substrate ratios. LinA2 is more substrate specific than LinB, the latter converted all tested HBCDs, LinA2 only one. The widespread HCH pollution favored the selection and evolution of bacteria converting these compounds. We found that LinA2 and LinB, two of these HCH-converting enzymes expressed in S. indicum B90A, also dehalogenate HBCDs to lower brominated compounds, indicating that structural similarities of both classes of compounds are recognized at the level of substrate-protein interactions.

  15. Not just angiotensinases: new roles for the angiotensin-converting enzymes.

    PubMed

    Lambert, Daniel W; Clarke, Nicola E; Turner, Anthony J

    2010-01-01

    The renin-angiotensin system (RAS) is a critical regulator of blood pressure and fluid homeostasis. Angiotensin II, the primary bioactive peptide of the RAS, is generated from angiotensin I by angiotensin-converting enzyme (ACE). A homologue of ACE, ACE2, is able to convert angiotensin II to a peptide with opposing effects, angiotensin-(1-7). It is proposed that disturbance of the balance of ACE and ACE2 expression and/or function is important in pathologies in which angiotensin II plays a role. These include cardiovascular and renal disease, lung injury and liver fibrosis. The critical roles of ACE and ACE2 in regulating angiotensin II levels have traditionally focussed attention on their activities as angiotensinases. Recent discoveries, however, have illuminated the roles of these enzymes and of the ACE2 homologue, collectrin, in intracellular trafficking and signalling. This paper reviews the key literature regarding both the catalytic and non-catalytic roles of the angiotensin-converting enzyme gene family.

  16. SALT SENSITIVITY IN RESPONSE TO RENAL INJURY REQUIRES RENAL ANGIOTENSIN-CONVERTING ENZYME

    PubMed Central

    Giani, Jorge F.; Bernstein, Kenneth E.; Janjulia, Tea; Han, Jiyang; Toblli, Jorge E.; Shen, Xiao Z.; Rodriguez-Iturbe, Bernardo; McDonough, Alicia A.; Gonzalez-Villalobos, Romer A.

    2015-01-01

    Recent evidence indicates that salt-sensitive hypertension can result from a subclinical injury that impairs the kidneys’ capacity to properly respond to a high salt diet. However, how this occurs is not well understood. Here, we showed that while previously salt resistant wild-type mice became salt-sensitive after the induction of renal injury with the nitric oxide synthase inhibitor Nω-Nitro-L-arginine methyl ester hydrochloride (L-NAME); mice lacking renal angiotensin-converting enzyme, exposed to the same insult, did not become hypertensive when faced with a sodium load. This is because the activity of renal angiotensin-converting enzyme plays a critical role in: 1) augmenting the local pool of angiotensin II and, 2) the establishment of the anti-natriuretic state via modulation of glomerular filtration rate and sodium tubular transport. Thus, this study demonstrates that the presence of renal angiotensin-converting enzyme plays a pivotal role in the development of salt sensitivity in response to renal injury. PMID:26150439

  17. Design of Peptide Substrate for Sensitively and Specifically Detecting Two Aβ-Degrading Enzymes: Neprilysin and Angiotensin-Converting Enzyme.

    PubMed

    Chen, Po-Ting; Chen, Chao-Long; Lin, Lilian Tsai-Wei; Lo, Chun-Hsien; Hu, Chaur-Jong; Chen, Rita P-Y; Wang, Steven S-S

    2016-01-01

    Upregulation of neprilysin (NEP) to reduce Aβ accumulation in the brain is a promising strategy for the prevention of Alzheimer's disease (AD). This report describes the design and synthesis of a quenched fluorogenic peptide substrate qf-Aβ(12-16)AAC (with the sequence VHHQKAAC), which has a fluorophore, Alexa-350, linked to the side-chain of its C-terminal cysteine and a quencher, Dabcyl, linked to its N-terminus. This peptide emitted strong fluorescence upon cleavage. Our results showed that qf-Aβ(12-16)AAC is more sensitive to NEP than the previously reported peptide substrates, so that concentrations of NEP as low as 0.03 nM could be detected at peptide concentration of 2 μM. Moreover, qf-Aβ(12-16)AAC had superior enzymatic specificity for both NEP and angiotensin-converting enzyme (ACE), but was inert with other Aβ-degrading enzymes. This peptide, used in conjunction with a previously reported peptide substrate qf-Aβ(1-7)C [which is sensitive to NEP and insulin-degrading enzyme (IDE)], could be used for high-throughput screening of compounds that only upregulate NEP. The experimental results of cell-based activity assays using both qf-Aβ(1-7)C and qf-Aβ(12-16)AAC as the substrates confirm that somatostatin treatment most likely upregulates IDE, but not NEP, in neuroblastoma cells.

  18. Design of Peptide Substrate for Sensitively and Specifically Detecting Two Aβ-Degrading Enzymes: Neprilysin and Angiotensin-Converting Enzyme

    PubMed Central

    Chen, Po-Ting; Chen, Chao-Long; Lin, Lilian Tsai-Wei; Lo, Chun-Hsien; Hu, Chaur-Jong; Chen, Rita P.-Y.; Wang, Steven S.-S.

    2016-01-01

    Upregulation of neprilysin (NEP) to reduce Aβ accumulation in the brain is a promising strategy for the prevention of Alzheimer’s disease (AD). This report describes the design and synthesis of a quenched fluorogenic peptide substrate qf-Aβ(12–16)AAC (with the sequence VHHQKAAC), which has a fluorophore, Alexa-350, linked to the side-chain of its C-terminal cysteine and a quencher, Dabcyl, linked to its N-terminus. This peptide emitted strong fluorescence upon cleavage. Our results showed that qf-Aβ(12–16)AAC is more sensitive to NEP than the previously reported peptide substrates, so that concentrations of NEP as low as 0.03 nM could be detected at peptide concentration of 2 μM. Moreover, qf-Aβ(12–16)AAC had superior enzymatic specificity for both NEP and angiotensin-converting enzyme (ACE), but was inert with other Aβ-degrading enzymes. This peptide, used in conjunction with a previously reported peptide substrate qf-Aβ(1–7)C [which is sensitive to NEP and insulin-degrading enzyme (IDE)], could be used for high-throughput screening of compounds that only upregulate NEP. The experimental results of cell-based activity assays using both qf-Aβ(1–7)C and qf-Aβ(12–16)AAC as the substrates confirm that somatostatin treatment most likely upregulates IDE, but not NEP, in neuroblastoma cells. PMID:27096746

  19. Angiotensin-I-Converting Enzyme (ACE) Inhibitors from Marine Resources: Prospects in the Pharmaceutical Industry

    PubMed Central

    Wijesekara, Isuru; Kim, Se-Kwon

    2010-01-01

    Hypertension or high blood pressure is one of the major independent risk factors for cardiovascular diseases. Angiotensin-I-converting enzyme (EC 3.4.15.1; ACE) plays an important physiological role in regulation of blood pressure by converting angiotensin I to angiotensin II, a potent vasoconstrictor. Therefore, the inhibition of ACE activity is a major target in the prevention of hypertension. Recently, the search for natural ACE inhibitors as alternatives to synthetic drugs is of great interest to prevent several side effects and a number of novel compounds such as bioactive peptides, chitooligosaccharide derivatives (COS) and phlorotannins have been derived from marine organisms as potential ACE inhibitors. These inhibitory derivatives can be developed as nutraceuticals and pharmaceuticals with potential to prevent hypertension. Hence, the aim of this review is to discuss the marine-derived ACE inhibitors and their future prospects as novel therapeutic drug candidates for treat hypertension. PMID:20479968

  20. Crystal Structures of Protein Glutaminase and Its Pro Forms Converted into Enzyme-Substrate Complex*

    PubMed Central

    Hashizume, Ryota; Maki, Yukiko; Mizutani, Kimihiko; Takahashi, Nobuyuki; Matsubara, Hiroyuki; Sugita, Akiko; Sato, Kimihiko; Yamaguchi, Shotaro; Mikami, Bunzo

    2011-01-01

    Protein glutaminase, which converts a protein glutamine residue to a glutamate residue, is expected to be useful as a new food-processing enzyme. The crystal structures of the mature and pro forms of the enzyme were refined at 1.15 and 1.73 Å resolution, respectively. The overall structure of the mature enzyme has a weak homology to the core domain of human transglutaminase-2. The catalytic triad (Cys-His-Asp) common to transglutaminases and cysteine proteases is located in the bottom of the active site pocket. The structure of the recombinant pro form shows that a short loop between S2 and S3 in the proregion covers and interacts with the active site of the mature region, mimicking the protein substrate of the enzyme. Ala-47 is located just above the pocket of the active site. Two mutant structures (A47Q-1 and A47Q-2) refined at 1.5 Å resolution were found to correspond to the enzyme-substrate complex and an S-acyl intermediate. Based on these structures, the catalytic mechanism of protein glutaminase is proposed. PMID:21926168

  1. Endothelin-Converting Enzymes and Related Metalloproteases in Alzheimer’s Disease

    PubMed Central

    Pacheco-Quinto, Javier; Herdt, Aimee; Eckman, Christopher B.; Eckman, Elizabeth A.

    2013-01-01

    The efficient clearance of amyloid β (Aβ) is essential to modulate levels of the peptide in the brain and to prevent it from accumulating in senile plaques, a hallmark of AD pathology. We and others have shown that failure in Aβ catabolism can produce elevations in Aβ concentration similar to those observed in familial forms of Alzheimer’s disease (AD). Based on the available evidence, it remains plausible that in late-onset AD, disturbances in the activity of Aβ degrading enzymes could induce Aβ accumulation, and that this increase could result in AD pathology. The following review presents a historical perspective of the parallel discovery of three vasopeptidases, neprilysin (NEP) and endothelin-converting enzymes-1 and -2 (ECE-1 and ECE-2), as important Aβ degrading enzymes. The recognition of the role of these vasopeptidases in Aβ degradation, beyond bringing to light a possible explanation of how cardiovascular risk factors may influence AD risk, highlights a possible risk of the use of inhibitors of these enzymes for other clinical indications such as hypertension. We will discuss in detail the experiments conducted to assess the impact of vasopeptidase deficiency (through pharmacological inhibition or genetic mutation) on Aβ accumulation, as well as the cooperative effect of multiple Aβ degrading enzymes to regulate concentration of the peptide at multiple sites, both intracellular and extracellular, throughout the brain. PMID:22903130

  2. Renal scintigraphy following angiotensin converting enzyme inhibition in the diagnosis of renovascular hypertension (captopril scintigraphy)

    SciTech Connect

    Sfakianakis, G.N. )

    1989-09-01

    This article describes the pathophysiology and primary causes of renovascular hypertension (RVH). No historical or physical finding is specific in the diagnosis of RVH, although onset of hypertension before the age of 30 years may suggest the possible presence of RVH. The physiology of the kidney is described along with the biochemistry of angiotensin converting enzyme inhibitors. The main thrust of the article is nuclear medicine techniques useful in the diagnosis of this disease. Several diagnositic methods are described but captopril scintigraphy is presented as a method that may give more optimal results in the diagnosis of RVH.

  3. Primary Systemic Amyloidosis and High Levels of Angiotensin-Converting Enzyme: Two Case Reports

    PubMed Central

    Praena-Segovia, J.; Sanchez-Gastaldo, A.; Bernabeu-Wittel, M.; Ocete-Pérez, R.; Ávila-Polo, R.; Martino, M. L.

    2013-01-01

    Infiltrative heart diseases are caused by a heterogeneous group of disorders; amyloidosis and sarcoidosis are two frequent causes of myocardial infiltration, which differ in clinical and biological outcome and treatment issues. The presence of high levels of angiotensin-converting enzyme (ACE) in a patient with infiltrative heart disease may increase suspicion of sarcoidosis. Nevertheless, no mention about increased ACE levels in extracerebral primary systemic amyloidosis is available. We present two cases of primary systemic amyloidosis, which are cardiac involvement and elevated ACE levels. PMID:24826302

  4. Angiotensin converting enzyme insertion or deletion polymorphism and coronary restenosis: meta-analysis of 16 studies

    PubMed Central

    Bonnici, François; Keavney, Bernard; Collins, Rory; Danesh, John

    2002-01-01

    Objective To assess the association between genotype at the insertion or deletion polymorphism of the angiotensin converting enzyme gene and risk of coronary restenosis after percutaneous coronary intervention. Design Meta-analysis of studies before July 2001 that reported on these genotypes and risk of coronary restenosis after a percutaneous coronary intervention, with or without coronary stenting. Results 16 studies, involving 4631 patients undergoing a percutaneous coronary intervention, yielded 1683 patients with restenosis after a mean weighted follow up of 5.5 months. The combined odds ratio for restenosis in people with the DD genotype was 1.23 (99% confidence interval 1.03 to 1.46). When studies were grouped by size, however, the combined odds ratios for restenosis in people with the DD genotype were 1.94 (1.39 to 2.71) for studies with less than 100 cases, 1.33 (0.92 to 1.93) for studies with 100-200 cases, and 0.92 (0.72 to 1.18) for studies with more than 200 cases (trend P=0.02). Similarly, when studies were grouped by genotyping procedures, significantly larger odds ratios were found in the studies that did not conceal disease status from laboratory staff and in the studies that did not use a second polymerase chain reaction amplification to reduce genetic mistyping. Conclusion Compared with other studies, larger and more rigorous studies show a weaker association between the angiotensin converting enzyme gene DD genotype and restenosis. Publication bias or detection biases can produce artefactual associations at least as large as those that might be expected for common polymorphisms in complex diseases, suggesting the need for larger and more rigorous genetic epidemiological investigations than are now customary. What is already known on this topicRestenosis after a percutaneous coronary intervention is one of the principal limitations of the techniqueGenotype at the angiotensin converting enzyme insertion or deletion polymorphism is proposed to be

  5. Changes in serum angiotensin I converting enzyme activity due to carbon disulfide exposure.

    PubMed

    Filipović, N; Bilalbegović, Z; Sefić, M; Djurić, D

    1984-01-01

    The activity of serum angiotensin I converting enzyme (ACE) was determined in 50 workers from a viscose factory in Banja Luka, Yugoslavia, and in 50 control subjects. Activity of serum ACE was significantly lower in workers exposed to carbon disulfide than in the control group. No correlation was found between a decrease of serum ACE in exposed workers and duration of exposure. These findings indicate that the serum ACE may be influenced by carbon disulfide, but the mechanism of these changes remains to be elucidated in this case.

  6. Role of angiotensin converting enzyme and angiotensinogen gene polymorphisms in angiotensin converting enzyme inhibitor-mediated antiproteinuric action in type 2 diabetic nephropathy patients

    PubMed Central

    Aggarwal, Neerja; Kare, Pawan Kumar; Varshney, Parul; Kalra, Om Prakash; Madhu, Sri Venkata; Banerjee, Basu Dev; Yadav, Anil; Raizada, Alpana; Tripathi, Ashok Kumar

    2017-01-01

    AIM To investigate the role of genetic variants of angiotensin converting enzyme (ACE) and angiotensinogen (AGT) genes in the antiproteinuric efficacy of ACE inhibitor therapy in diabetic nephropathy (DN) patients. METHODS In the present study, 270 type 2 diabetes mellitus patients with nephropathy were enrolled and treated with ACE inhibitor (ramipril) and followed at 6 mo for renal function and albumin excretion by estimating serum creatinine, end stage renal disease, and albumin/creatinine ratio (ACR) in urine. Genotyping of ACE I/D and AGT M235T polymorphisms were performed by using primer specific polymerase chain reaction (PCR) and PCR-RFLP techniques, respectively. RESULTS Forty-eight percent of DN patients (responders) benefited with respect to proteinuria from ACE inhibitor therapy at 6 mo follow-up. A significant reduction in ACR was observed after 6 mo treatment with ACE inhibitor irrespective of whether DN patients were micro-albuminuric (≥ 30 and < 300 mg/g creatinine) or macro-albuminuric (≥ 300 mg/g creatinine) at the time of enrollment. However, macro-albuminuric patients (55%) showed better response to therapy. A reduction in urinary ACR was found independent of genotypes of ACE I/D and AGT M235T polymorphisms although macro-albuminuric patients having TT genotype showed statistically insignificant increased response (72%). CONCLUSION ACE inhibitor therapy reduced urinary ACR by ≥ 30% in 50% of DN patients and the response is independent of ACE I/D and AGT M235T polymorphisms. PMID:28344754

  7. Cellular expression of isoforms of endothelin-converting enzyme-1 (ECE-1c, ECE-1b and ECE-1a) and endothelin-converting enzyme-2.

    PubMed

    Davenport, A P; Kuc, R E

    2000-11-01

    Our aim was to compare the cellular expression of endothelin-converting enzyme-1 (ECE-1) isoforms and ECE-2 using immunocytochemistry in normal and diseased human tissue. Intense ECE-1b immunoreactivity was present within renal and pulmonary epithelial cells with lower levels of staining displayed by ECE-1c, ECE-1a and ECE-2 antisera. Staining was detected with all antisera (except ECE-1a) within the endothelium of renal and pulmonary vessels having a range of lumen diameters as well as pial arteries and intracerebral vessels penetrating brain. ECE-1b, ECE-1c and ECE-2 immunoreactivity was localized to perivascular astrocytes and neuronal processes in the cerebral cortex. In diseased vessels, ECE-1c, ECE-1b and ECE-2 antisera stained macrophages infiltrating atherosclerotic plaques within coronary arteries. These results suggest ECE-1b and ECE-2 may be widely expressed in normal tissue from humans and inhibition of ECE-1 isoforms and ECE-2 expressed by cells such as macrophages in pathophysiological tissue may be an additional therapeutic target in cardiovascular disease.

  8. Angiotensin converting enzyme versus angiotensin converting enzyme-2 selectivity of MLN-4760 and DX600 in human and murine bone marrow-derived cells

    PubMed Central

    Joshi, Shrinidh; Balasubramanian, Narayanaganesh; Vasam, Goutham; Jarajapu, Yagna PR

    2016-01-01

    Angiotensin-converting enzymes, ACE and ACE2, are key members of renin angiotensin system. Activation of ACE2/Ang-(1-7) pathway enhances cardiovascular protective functions of bone marrow-derived stem/progenitor cells. The current study evaluated the selectivity of ACE2 inhibitors, MLN-4760 and DX-600, and ACE and ACE2 activities in human (hu) and murine (mu) bone marrow cells. Assays were carried out in hu and mu mononuclear cells (MNCs) and huCD34+ cells or mu-lineage-depleted (muLin-) cells, human-recombinant (rh) enzymes, and mu-heart with enzyme-specific substrates. ACE or ACE2 inhibition by racemic MLN-4760, its isomers MLN-4760-A and MLN-4760-B, DX600 and captopril were characterized. MLN-4760-B is relatively less efficacious and less-selective than the racemate or MLN-4760-A at hu-rhACE2, and all three of them inhibited 43% rhACE. In huMNCs, MLN-4760-B detected 63% ACE2 with 28-fold selectivity over ACE. In huCD34+ cells, MLN-4760-B detected 38% of ACE2 activity with 63-fold selectivity. In mu-heart and muMNCs, isomer B was 100- and 228-fold selective for ACE2, respectively. In muLin- cells, MLN-4760-B detected 25% ACE2 activity with a pIC50 of 6.3. The racemic mixture and MLN-4760-A showed lower efficacy and poor selectivity for ACE2 in MNCs and mu-heart. ACE activity detected by captopril was 32 and 19%, respectively, in huCD34+ and muLin- cells. DX600 was less efficacious, and more selective for ACE2 compared to MLN-4760-B in all samples tested. These results suggest that MLN-4760-B is a better antagonist of ACE2 than DX600 at 10μM concentration in human and murine bone marrow cells, and that these cells express more functional ACE2 than ACE. PMID:26851370

  9. Producing enzymes from molds to convert cellulose into glucose and alcohol. Final report

    SciTech Connect

    Bassi, S.; Curran, P.

    1982-11-29

    The following significant results were obtained: (1) extracts of various tree barks were made and used to determine if any of the chemicals had growth stimulating effects on the molds. The extracts from the oak and elm tree bark were very active in inducing and stimulating the mycelial growth of the molds Trichoderma reesei, Pleurotus ostreatus and Aspergillus awamori. Efforts to determine what specific chemical caused the increase in growth were unsuccessful but are being continued. This information will be very useful because it was discovered that by speeding and increasing the growth of the mold cells, it was also possible to speed and increase the production of the enzymes; (2) efforts to cultivate the mold Pleurotus ostreatus in the same culture with Trichoderma reesei were successful. When the two molds were cultured on an enriched cellulose media, it was discovered that the reesei produced large amounts of the beta glucosidase. Reesei produces very small amounts of this enzyme under normal conditions but this high production under coculture conditions may be due to the fact that Pleurotus ostreatus removes the glucose formed from the cellulose breakdown. Trichoderma reesei produces cellulases which convert cellulose into cellobiose and cellobiose is converted to glucose by the enzyme beta-glucosidase. In the presence of glucose the gene producing beta-glucosidase is repressed by the feedback mechanism. These surplus enzymes can then be used for saccharifying cellulose from wastepaper, wood pulp, cornstalks, wheat straw and other cellulosic materials and eventually produce alcohol; (3) efforts to produce mutants of the Trichoderma reesei by using the uv irradiation were unsuccessful; and (4) Zymomonas mobilis is capable of faster fermentation. The only drawback is that only low concentrations of glucose can be used. Mutants of Zymomonas resistant to higher alcohol levels would help in this process and are being looked into.

  10. Characterization of angiotensin I-converting enzyme from anterior gills of the mangrove crab Ucides cordatus.

    PubMed

    Bersanetti, Patrícia A; Nogueira, Regina F; Marcondes, Marcelo F; Paiva, Paulo B; Juliano, Maria A; Juliano, Luiz; Carmona, Adriana K; Zanotto, Flavia P

    2015-03-01

    Angiotensin I-converting enzyme (ACE) is a well-known metallopeptidase that is found in vertebrates, invertebrates and bacteria. We isolated from the anterior gill of the crab Ucides cordatus an isoform of ACE, here named crab-ACE, which presented catalytic properties closely resembling to those of mammalian ACE. The enzyme was purified on Sepharose-lisinopril affinity chromatography to apparent homogeneity and a band of about 72 kDa could be visualized after silver staining and Western blotting. Assays performed with fluorescence resonance energy transfer (FRET) selective ACE substrates Abz-FRK(Dnp)P-OH, Abz-SDK(Dnp)P-OH and Abz-LFK(Dnp)-OH, allowed us to verify that crab-ACE has hydrolytic profile very similar to that of the ACE C-domain. In addition, we observed that crab-ACE can hydrolyze the ACE substrates, angiotensin I and bradykinin. The enzyme was strongly inhibited by the specific ACE inhibitor lisinopril (Ki of 1.26 nM). However, in contrast to other ACE isoforms, crab-ACE presented a very particular optimum pH, being the substrate Abz-FRK(Dnp)-P-OH hydrolyzed efficiently at pH 9.5. Other interesting characteristic of crab-ACE was that the maximum hydrolytic activity was reached at around 45°C. The description of an ACE isoform in Ucides cordatus is challenging and may contribute to a better understanding of the biochemical function of this enzyme in invertebrates.

  11. Metabolism of vasoactive peptides by human endothelial cells in culture. Angiotensin I converting enzyme (kininase II) and angiotensinase.

    PubMed

    Johnson, A R; Erdös, E G

    1977-04-01

    Cultured endothelial cells provide a model for the study of interactions of vasoactive peptides with endothelium. Endothelial cell cultured from veins of human umbilical cords contain both angiotensin I converting enzyme (kininase II) and angiotensinase activities. Intact monolayers of cells can both activate angiotensin I and inactivate bradykinin when the peptides are added to culture flasks in protein-free medium. Intact suspended cells or lysed cells convert angiotensin I to angiotensin II, inactivate bradykinin, and hydrolyze hippuryldiglycine to hippuric acid and diglycine. These actions are inhibited by SQ 20881, the specific inhibitor of converting enzyme. The kininase activity of endothelial cells was partially inhibited by antibody to human lung converting enzyme. Endothelial cells also inactivate longer analogs of bradykinin, such as kallidin, methionyl-lysyl bradykinin, and bradykinin coupled covalently to 500,000 mol wt dextran. The endothelial cells retained converting enzyme activity through four successive subcultures, indicating that the enzyme is synthesized by the cells surface, and it is apparently a marker for endothelial cells, since cultured human fibroblasts, smooth muscle cells, and baby hamster kidney cells do not have it. Endothelial cells also contain an aminopheptidase which hydrolyzes both angiotensin II and the synthetic substrate, alpha-L-aspartyl beta-naphthylamide. The angiotensinase activity increased when the cells were lysed, which suggests that the enzyme is localized within the cells, Hydrolysis of both alpha-L-aspartyl beta-naphthylamide and angiotensin II was inhibited by omicron-phenanthroline, indicating that the enzyme is an A-tipe anigotensinase.

  12. The pharmacological mechanism of angiotensin-converting enzyme inhibition by green tea, Rooibos and enalaprilat - a study on enzyme kinetics.

    PubMed

    Persson, Ingrid A-L

    2012-04-01

    Green tea (Camellia sinensis L.) and Rooibos (Aspalathus linearis Dahlg.) inhibit angiotensin-converting enzyme (ACE) in vitro and in vivo. The ACE inhibitor enalaprilat has been described previously as a competitive inhibitor and sometimes as a non-competitive inhibitor. The aim of this study was to investigate the pharmacological mechanism of ACE inhibition of green tea and Rooibos by enzyme kinetics, and to compare this with enalaprilat. A Michaelis-Menten kinetics and Lineweaver-Burk graph showed mean values of V(max)  = 3.73 µM and K(m)  = 0.71 µM for green tea, of V(max)  = 6.76 µM and K(m)  = 0.78 µM for Rooibos, of V(max)  = 12.54 µM and K(m)  = 2.77 µM for enalaprilat, and of V(max)  = 51.33 µM and K(m)  = 9.22 µM for the PBS control. Incubating serum with green tea or Rooibos saturated with zinc chloride did not change the inhibitory effect. Enalaprilat preincubated with zinc chloride showed a decrease in the inhibitory effect. In conclusion, green tea, Rooibos and enalaprilat seem to inhibit ACE activity using a mixed inhibitor mechanism.

  13. The effect of angiotensin-converting enzyme inhibition throughout a superovulation protocol in ewes.

    PubMed

    Pereira, Alécio Matos; de Souza Júnior, Antônio; Machado, Fernanda Brandão; Gonçalves, Gleisy Kelly Neves; Feitosa, Lauro César Soares; Reis, Adelina Martha; Santos, Robson Augusto Souza; Honorato-Sampaio, Kinulpe; Costa, Amilton Raposo

    2015-12-01

    Many studies identified new components of the renin–angiotensin system (RAS), such as Angiotensin-(1-7) [Ang-(1–7)] and Angiotensin-converting enzyme type 2 (ACE2), in mammalian ovaries.We previously showed Angiotensin-Converting Enzyme (ACE) inhibition, which increases the level of Ang-(1–7), stimulated ovarian estradiol output in ewe after estrous synchronization. Considering that Ang-(1–7) stimulates ovarian function and elevated estradiol before ovulation is associated with increased chance of achieving pregnancy, the present study investigated whether ACE inhibition throughout a superovulation protocol in ewe might improve ovulation outcome. At first, immunohistochemistry in ovaries of nonpregnant ewes revealed localization of Angiotensin II (Ang II), Ang-(1–7) and ACE2 in theca cells of antral follicles and in corpus luteum. Ang II and Ang-(1–7)were also detected in follicular fluid (FF) by Radioimmunoassay (RIA). Enalapril treatment throughout the superovulation protocol decreased 17β-estradiol (E2) output and raised progesterone:estradiol (P4:E2) ratio without a direct influence on ovulation and quality of embryos.

  14. Inhibition of angiotensin-converting enzyme increases oestradiol production in ewes submitted to oestrous synchronization protocol.

    PubMed

    Costa, A s; Junior, A S; Viana, G E N; Muratori, M C S; Reis, A M; Costa, A P R

    2014-10-01

    This study aimed at evaluating the effects of angiotensin-converting enzyme inhibitor (enalapril) and angiotensin II antagonist (valsartan) on the oestradiol and progesterone production in ewes submitted to oestrous synchronization protocol. The animals were weighed and randomly divided into three groups (n = 7). A pre-experiment conducted to verify the effectiveness and toxicity of enalapril (0.5 mg/kg LW) and valsartan (2.2 mg/kg LW) showed that, in the doses used, these drugs were effective in reducing blood pressure without producing toxic effects. In the experiment, all animals were subjected to oestrous synchronization protocol during 12 days. On D10, D11 and D12, animals received saline, enalapril or valsartan (same doses of the pre-experiment), according to the group randomly divided. The hormonal analysis showed an increase in oestradiol on the last day of the protocol (D12) in animals that received enalapril (p < 0.05), but not in other groups, without changing the concentration of progesterone in any of the treatments. It is concluded that valsartan and enalapril are safe and effective subcutaneously for use in sheep and that the angiotensin-converting enzyme (ACE) inhibition with enalapril leads to an increase in oestradiol production near ovulation without changing the concentration of progesterone. This shows that ACE inhibition may be a useful tool in reproductive biotechnologies involving induction and synchronization of oestrus and ovulation in sheep.

  15. A Modern Understanding of the Traditional and Nontraditional Biological Functions of Angiotensin-Converting Enzyme

    PubMed Central

    Ong, Frank S.; Blackwell, Wendell-Lamar B.; Shah, Kandarp H.; Giani, Jorge F.; Gonzalez-Villalobos, Romer A.; Shen, Xiao Z.; Fuchs, Sebastien

    2013-01-01

    Angiotensin-converting enzyme (ACE) is a zinc-dependent peptidase responsible for converting angiotensin I into the vasoconstrictor angiotensin II. However, ACE is a relatively nonspecific peptidase that is capable of cleaving a wide range of substrates. Because of this, ACE and its peptide substrates and products affect many physiologic processes, including blood pressure control, hematopoiesis, reproduction, renal development, renal function, and the immune response. The defining feature of ACE is that it is composed of two homologous and independently catalytic domains, the result of an ancient gene duplication, and ACE-like genes are widely distributed in nature. The two ACE catalytic domains contribute to the wide substrate diversity of ACE and, by extension, the physiologic impact of the enzyme. Several studies suggest that the two catalytic domains have different biologic functions. Recently, the X-ray crystal structure of ACE has elucidated some of the structural differences between the two ACE domains. This is important now that ACE domain-specific inhibitors have been synthesized and characterized. Once widely available, these reagents will undoubtedly be powerful tools for probing the physiologic actions of each ACE domain. In turn, this knowledge should allow clinicians to envision new therapies for diseases not currently treated with ACE inhibitors. PMID:23257181

  16. Marketing research on the angiotensin-converting enzyme inhibitors antihypertensive medicines

    PubMed Central

    BOBOIA, ANAMARIA; GRIGORESCU, MARIUS RAREŞ; TURCU - ŞTIOLICĂ, ADINA

    2017-01-01

    Background and aims The research aimed at investigating sales trends of angiotensin-converting enzyme inhibitors antihypertensive medicines, both in terms of quantity and value, in ten community pharmacies, for a period of three years. The research on the antihypertensive medicines consumption is important for highlighting the ever increasing impact of hypertension among the population. Methods The methods used in this research were the following: marketing research, method of sampling, descriptive methods, retrospective analysis, method of comparison. Results The results showed that the drugs containing the active substances of the angiotensin converting enzyme inhibitors class had had significant increases in quantitative and value sales, bringing substantial revenues to pharmacies. From the quantitative perspective, the best-selling products were those containing Enalaprilum, while in terms of value, the best-selling medicines were those containing Perindoprilum. We evidenced that spectacular sales were also achieved for products that have Lisinoprilum, respectively Captoprilum, as active substances. The largest quantities were marketed for the Captopril Terapia® product and the highest earnings were recorded for the Prestarium® medicine. Conclusion This paper approaches an interesting and topical issue, which can be helpful to professionals (pharmacists, doctors) and other categories, such as economists, statisticians, representatives of companies manufacturing medicines, as well as to hypertensive patients, as it could be used to warn population regarding the incidence of cardiovascular diseases, and, at the same time, trace sales trends in order to accomplish profitable business plans. PMID:28246502

  17. Effect of inhibition of converting enzyme on renal hemodynamics and sodium management in polycystic kidney disease.

    PubMed

    Torres, V E; Wilson, D M; Burnett, J C; Johnson, C M; Offord, K P

    1991-10-01

    We compared the tubular transport of sodium and the erythrocyte sodium-lithium countertransport activity in hypertensive patients with autosomal dominant polycystic kidney disease (ADPKD) and in normotensive control subjects. In addition, we assessed the effects of inhibition of converting enzyme on renal hemodynamics and sodium excretion in hypertensive patients with ADPKD to provide information on mechanisms responsible for the increased renal vascular resistance and filtration fraction and the adjustment of the pressure-natriuresis relationship during saline expansion, observed in patients with ADPKD, hypertension, and preserved renal function. In comparison with normotensive control subjects, the hypertensive patients with ADPKD had lower renal plasma flows, higher renal vascular resistances and filtration fractions, and similar proximal and distal fractional reabsorptions of sodium. The administration of enalapril resulted in significant increases in the renal plasma flow and significant reductions in mean arterial pressure, renal vascular resistance, and filtration fraction, but the glomerular filtration rate remained unchanged. Despite the significant reduction in mean arterial pressure during inhibition of converting enzyme, the distal fractional reabsorption of sodium decreased while the total fractional excretion of sodium remained unchanged or increased slightly. No significant differences were detected between the normotensive control subjects and the hypertensive patients with ADPKD in erythrocyte sodium-lithium countertransport activity, plasma renin activity, plasma aldosterone concentration, or atrial natriuretic factor. These results suggest that the renal renin-angiotensin system plays a central role in the alterations in renal hemodynamics and sodium management associated with the development of hypertension in ADPKD.

  18. A quantitative peptidomics approach to unravel immunological functions of angiotensin converting enzyme in Locusta migratoria.

    PubMed

    Duressa, Tewodros Firdissa; Boonen, Kurt; Huybrechts, Roger

    2016-09-01

    Locusta migratoria angiotensin converting enzyme (LmACE) is encoded by multiple exons displaying variable number of genomic duplications. Treatments of lipopolysaccharide (LPS) as well as peptidoglycan but not β-1-3 glucan resulted in enhanced expression of angiotensin converting enzyme in hemocytes of Locusta migratoria. No such effect was observed in fat body cells. Differential peptidomics using locust plasma samples post infection with LPS in combination with both an LmACE transcript knockdown by RNAi and a functional knockdown using captopril allowed the identification of 5 circulating LPS induced peptides which only appear in the hemolymph of locust having full LmACE functionality. As these peptides originate from larger precursor proteins such as locust hemocyanin-like protein, having known antimicrobial properties, the obtained results suggest a possible direct or indirect role of LmACE in the release of these peptides from their precursors. Additionally, this experimental setup confirmed the role of LmACE in the clearance of multiple peptides from the hemolymph.

  19. The angiotensin converting enzyme inhibitor captopril protects nigrostriatal dopamine neurons in animal models of parkinsonism.

    PubMed

    Sonsalla, Patricia K; Coleman, Christal; Wong, Lai-Yoong; Harris, Suzan L; Richardson, Jason R; Gadad, Bharathi S; Li, Wenhao; German, Dwight C

    2013-12-01

    Parkinson's disease (PD) is a progressive neurodegenerative disorder characterized by a prominent loss of nigrostriatal dopamine (DA) neurons with an accompanying neuroinflammation. The peptide angiotensin II (AngII) plays a role in oxidative-stress induced disorders and is thought to mediate its detrimental actions via activation of AngII AT1 receptors. The brain renin-angiotensin system is implicated in neurodegenerative disorders including PD. Blockade of the angiotensin converting enzyme or AT1 receptors provides protection in acute animal models of parkinsonism. We demonstrate here that treatment of mice with the angiotensin converting enzyme inhibitor captopril protects the striatum from acutely administered 1-methyl-4-phenyl-1,2,3,6-tetrahydropyrine (MPTP), and that chronic captopril protects the nigral DA cell bodies from degeneration in a progressive rat model of parkinsonism created by the chronic intracerebral infusion of 1-methyl-4-phenylpyridinium (MPP+). The accompanying activation of microglia in the substantia nigra of MPP+-treated rats was reduced by the chronic captopril treatment. These findings indicate that captopril is neuroprotective for nigrostriatal DA neurons in both acute and chronic rodent PD models. Targeting the brain AngII pathway may be a feasible approach to slowing neurodegeneration in PD.

  20. The endothelin system and endothelin-converting enzyme in the brain: molecular and cellular studies.

    PubMed

    Barnes, K; Turner, A J

    1997-08-01

    The biologically active vasoactive peptides, the endothelins (ETs), are generated from inactive intermediates, the big endothelins, by a unique processing event catalysed by the zinc metalloprotease, endothelin converting enzyme (ECE). In this overview we examine the actions of endothelins in the brain, and focus on the structure and cellular locations of ECE. The heterogeneous distribution in the brain of ET-1, ET-2, and ET-3 is discussed in relation to their hemodynamic, mitogenic and proliferative properties as well as their possible roles as neurotransmitters. The cellular and subcellular localization of ECE in neuronal and in glial cells is compared with that of other brain membrane metalloproteases, neutral endopeptidase-24.11 (neprilysin), angiotensin converting enzyme and aminopeptidase N, which all function in neuropeptide processing and metabolism Unlike these ectoenzymes, ECE exhibits a dual localisation in the cell, being present on the plasma membrane and also, in some instances, being concentrated in a perinuclear region. This differential localization may reflect distinct targeting of different ECE isoforms, ECE-1 alpha, ECE-1 beta, and ECE-2.

  1. Prevalence of the angiotensin I converting enzyme insertion/deletion polymorphism, plasma angiotensin converting enzyme activity, and left ventricular mass in a normotensive Chilean population.

    PubMed

    Jalil, J E; Piddo, A M; Cordova, S; Chamorro, G; Braun, S; Jalil, R; Vega, J; Jadue'P, L; Lavandero, S; Lastra, P

    1999-07-01

    The aim of this study was to estimate the prevalence of the different alleles of the angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism and associated plasma ACE activity, as well as cardiac echocardiographic structure, in a healthy Chilean population. We selected 117 healthy normotensive subjects (aged 45 to 60 years, middle socioeconomic status, nonobese, and nondiabetic) from a population-based study concerning the prevalence of risk factors for chronic diseases (Conjunto de Acciones Para la Reducción Multifactorial de las Enfermedades no Transmisibles [CARMEN]). The frequencies of the I and D alleles were 0.57 and 0.43, respectively. Mean plasma ACE activity was 15.3 +/- 3.9 U/mL. Compared with subjects with the II genotype, plasma ACE activity was significantly higher in subjects with the ID and DD genotypes with no difference between them. No correlation was observed between blood pressure and plasma ACE activity. Among the three different genotypes there was no difference in left ventricular (LV) dimensions or in LV mass. No correlation between plasma ACE activity and LV mass was observed for either gender or different genotypes. Multivariate linear regression analysis using LV mass and LV mass index as dependent variables showed independent effects (P < .05) for gender (higher LV mass in men) and diastolic blood pressure, but not for the DD genotype. In conclusion, in this population, the presence of the D allele on the ACE gene determined higher circulating ACE activity. However, in this normotensive healthy population, male gender and diastolic blood pressure, but not the presence of the D allele, were associated with increased LV mass.

  2. Angiotensin-converting enzyme gene polymorphism predicts the time-course of blood pressure response to angiotensin converting enzyme inhibition in the AASK trial

    PubMed Central

    Bhatnagar, Vibha; O’Connor, Daniel T.; Schork, Nicholas J.; Salem, Rany M.; Nievergelt, Caroline M.; Rana, Brinda K.; Smith, Douglas W.; Bakris, George L.; Middleton, John P.; Norris, Keith C.; Wright, Jackson T.; Cheek, Deanna; Hiremath, Leena; Contreras, Gabriel; Appel, Lawrence J.; Lipkowitz, Michael S.

    2009-01-01

    Objective It has yet to be determined whether genotyping at the angiotensin-converting enzyme (ACE) locus is predictive of blood pressure response to an ACE inhibitor. Methods Participants from the African American Study of Kidney Disease and Hypertension trial randomized to the ACE inhibitor ramipril (n = 347) were genotyped at three polymorphisms on ACE, just downstream from the ACE insertion/deletion polymorphism (Ins/Del): G12269A, C17888T, and G20037A. Time to reach target mean arterial pressure (≤ 107 mmHg) was analyzed by genotype and ACE haplotype using Kaplan–Meier survival curves and Cox proportional hazard models. Results Individuals with a homozygous genotype at G12269A responded significantly faster than those with a heterozygous genotype; the adjusted (average number of medications and baseline mean arterial pressure) hazard ratio (homozygous compared to heterozygous genotype) was 1.86 (95% confidence limits 1.32–3.23; P < 0.001 for G12269A genotype). The adjusted hazard ratio for participants with homozygous ACE haplotypes compared to those heterozygous ACE haplotypes was 1.40 (1.13–1.75; P = 0.003 for haplotype). The ACE genotype effects were specific for ACE inhibition (i.e., not seen among those randomized to a calcium channel blocker), and were independent of population stratification. Conclusions African-Americans with a homozygous genotype at G12269A or homozygous ACE haplotypes responded to ramipril significantly faster than those with a heterozygous genotype or heterozygous haplotypes, suggesting that heterosis may be an important determinant of responsiveness to an ACE inhibitor. These associations may be a result of biological activity of this polymorphism, or of linkage disequilibrium with nearby variants such as the ACE Ins/Del, perhaps in the regulation of ACE splicing. PMID:17885551

  3. Effect of angiotensin-converting enzyme inhibitors on vascular endothelial function in hypertensive patients after intensive periodontal treatment.

    PubMed

    Rubio, María C; Lewin, Pablo G; De la Cruz, Griselda; Sarudiansky, Andrea N; Nieto, Mauricio; Costa, Osvaldo R; Nicolosi, Liliana N

    2016-04-01

    There is a relation between vascular endothelial function, atherosclerotic disease, and inflammation. Deterioration of endothelial function has been observed twenty-four hours after intensive periodontal treatment. This effect may be counteracted by the action of angiotensin-converting enzyme inhibitors, which improve endothelial function. The aim of the present study was to evaluate vascular endothelial function after intensive periodontal treatment, in hypertensive patients treated with angiotensinconverting enzyme inhibitors. A prospective, longitudinal, comparative study involving repeated measurements was conducted. Fifty-two consecutive patients with severe periodontal disease were divided into two groups, one comprising hypertensive patients treated with converting enzyme inhibitors and the other comprising patients with no clinical signs of pathology and not receiving angiotensin-converting enzyme inhibitors. Endothelial function was assessed by measuring postischemic dilation of the humeral artery (baseline echocardiography Doppler), and intensive periodontal treatment was performed 24h later. Endothelial function was re-assessed 24h and 15 days after periodontal treatment.

  4. Novel natural peptide substrates for endopeptidase 24.15, neurolysin, and angiotensin-converting enzyme.

    PubMed

    Rioli, Vanessa; Gozzo, Fabio C; Heimann, Andrea S; Linardi, Alessandra; Krieger, José E; Shida, Cláudio S; Almeida, Paulo C; Hyslop, Stephen; Eberlin, Marcos N; Ferro, Emer S

    2003-03-07

    Endopeptidase 24.15 (EC; ep24.15), neurolysin (EC; ep24.16), and angiotensin-converting enzyme (EC; ACE) are metallopeptidases involved in neuropeptide metabolism in vertebrates. Using catalytically inactive forms of ep24.15 and ep24.16, we have identified new peptide substrates for these enzymes. The enzymatic activity of ep24.15 and ep24.16 was inactivated by site-directed mutagenesis of amino acid residues within their conserved HEXXH motifs, without disturbing their secondary structure or peptide binding ability, as shown by circular dichroism and binding assays. Fifteen of the peptides isolated were sequenced by electrospray ionization tandem mass spectrometry and shared homology with fragments of intracellular proteins such as hemoglobin. Three of these peptides (PVNFKFLSH, VVYPWTQRY, and LVVYPWTQRY) were synthesized and shown to interact with ep24.15, ep24.16, and ACE, with K(i) values ranging from 1.86 to 27.76 microm. The hemoglobin alpha-chain fragment PVNFKFLSH, which we have named hemopressin, produced dose-dependent hypotension in anesthetized rats, starting at 0.001 microg/kg. The hypotensive effect of the peptide was potentiated by enalapril only at the lowest peptide dose. These results suggest a role for hemopressin as a vasoactive substance in vivo. The identification of these putative intracellular substrates for ep24.15 and ep24.16 is an important step toward the elucidation of the role of these enzymes within cells.

  5. Angiotensin converting enzyme in the brain, testis, epididymis, pituitary gland and adrenal gland

    SciTech Connect

    Strittmatter, S.M.

    1986-01-01

    (/sup 3/H)Captopril binds to angiotensin converting enzyme (ACE) in rat tissue homogenates. The pharmacology, regional distribution and copurification of (/sup 3/H)captopril binding with enzymatic activity demonstrate the selectivity of (/sup 3/H)captopril labeling of ACE. (/sup 3/H)Captopril binding to purified ACE reveals differences in cationic dependence and anionic regulation between substrate catalysis and inhibitor recognition. (/sup 3/H)Captopril association with ACE is entropically driven. The selectivity of (/sup 3/H)captopril binding permits autoradiographic localization of the ACE in the brain, male reproductive system, pituitary gland and adrenal gland. In the brain, ACE is visualized in a striatonigral neuronal pathway which develops between 1 and 7 d after birth. In the male reproductive system, (/sup 3/H)captopril associated silver grains are found over spermatid heads and in the lumen of seminiferous tubules in stages I-VIII and XII-XIV. In the pituitary gland, ACE is localized to the posterior lobe and patches of the anterior lobe. The adrenal medulla contains moderate ACE levels while low levels are found in the adrenal cortex. Adrenal medullary ACE is increased after hypophysectomy and after reserpine treatment. The general of ligand binding techniques for the study of enzymes is demonstrated by the specific labeling of another enzyme, enkephaline convertase, in crude tissue homogenates by the inhibitor (/sup 3/H)GEMSA.

  6. The critical role of tissue angiotensin-converting enzyme as revealed by gene targeting in mice.

    PubMed Central

    Esther, C R; Marino, E M; Howard, T E; Machaud, A; Corvol, P; Capecchi, M R; Bernstein, K E

    1997-01-01

    Angiotensin-converting enzyme (ACE) generates the vasoconstrictor angiotensin II, which plays a critical role in maintenance of blood pressure in mammals. Although significant ACE activity is found in plasma, the majority of the enzyme is bound to tissues such as the vascular endothelium. We used targeted homologous recombination to create mice expressing a form of ACE that lacks the COOH-terminal half of the molecule. This modified ACE protein is catalytically active but entirely secreted from cells. Mice that express only this modified ACE have significant plasma ACE activity but no tissue-bound enzyme. These animals have low blood pressure, renal vascular thickening, and a urine concentrating defect. The phenotype is very similar to that of completely ACE-deficient mice previously reported, except that the renal pathology is less severe. These studies strongly support the concept that the tissue-bound ACE is essential to the control of blood pressure and the structure and function of the kidney. PMID:9153279

  7. Alzheimer's disease beta-amyloid peptide is increased in mice deficient in endothelin-converting enzyme.

    PubMed

    Eckman, Elizabeth A; Watson, Mona; Marlow, Laura; Sambamurti, Kumar; Eckman, Christopher B

    2003-01-24

    The abnormal accumulation of beta-amyloid (Abeta) in the brain is an early and invariant feature in Alzheimer's disease (AD) and is believed to play a pivotal role in the etiology and pathogenesis of the disease. As such, a major focus of AD research has been the elucidation of the mechanisms responsible for the generation of Abeta. As with any peptide, however, the degree of Abeta accumulation is dependent not only on its production but also on its removal. In cell-based and in vitro models we have previously characterized endothelin-converting enzyme-1 (ECE-1) as an Abeta-degrading enzyme that appears to act intracellularly, thus limiting the amount of Abeta available for secretion. To determine the physiological significance of this activity, we analyzed Abeta levels in the brains of mice deficient for ECE-1 and a closely related enzyme, ECE-2. Significant increases in the levels of both Abeta40 and Abeta42 were found in the brains of these animals when compared with age-matched littermate controls. The increase in Abeta levels in the ECE-deficient mice provides the first direct evidence for a physiological role for both ECE-1 and ECE-2 in limiting Abeta accumulation in the brain and also provides further insight into the factors involved in Abeta clearance in vivo.

  8. Monocyte Tumor Necrosis Factor-α–Converting Enzyme Catalytic Activity and Substrate Shedding in Sepsis and Noninfectious Systemic Inflammation*

    PubMed Central

    O’Callaghan, David J. P.; O’Dea, Kieran P.; Scott, Alasdair J.; Takata, Masao

    2015-01-01

    Objectives: To determine the effect of severe sepsis on monocyte tumor necrosis factor-α–converting enzyme baseline and inducible activity profiles. Design: Observational clinical study. Setting: Mixed surgical/medical teaching hospital ICU. Patients: Sixteen patients with severe sepsis, 15 healthy volunteers, and eight critically ill patients with noninfectious systemic inflammatory response syndrome. Interventions: None. Measurements and Main Results: Monocyte expression of human leukocyte antigen-D-related peptide, sol-tumor necrosis factor production, tumor necrosis factor-α–converting enzyme expression and catalytic activity, tumor necrosis factor receptor 1 and 2 expression, and shedding at 48-hour intervals from day 0 to day 4, as well as p38-mitogen activated protein kinase expression. Compared with healthy volunteers, both sepsis and systemic inflammatory response syndrome patients’ monocytes expressed reduced levels of human leukocyte antigen-D-related peptide and released less sol-tumor necrosis factor on in vitro lipopolysaccharide stimulation, consistent with the term monocyte deactivation. However, patients with sepsis had substantially elevated levels of basal tumor necrosis factor-α–converting enzyme activity that were refractory to lipopolysaccharide stimulation and this was accompanied by similar changes in p38-mitogen activated protein kinase signaling. In patients with systemic inflammatory response syndrome, monocyte basal tumor necrosis factor-α–converting enzyme, and its induction by lipopolysaccharide, appeared similar to healthy controls. Changes in basal tumor necrosis factor-α–converting enzyme activity at day 0 for sepsis patients correlated with Acute Physiology and Chronic Health Evaluation II score and the attenuated tumor necrosis factor-α–converting enzyme response to lipopolysaccharide was associated with increased mortality. Similar changes in monocyte tumor necrosis factor-α–converting enzyme activity could

  9. Naturally occurring active N-domain of human angiotensin I-converting enzyme.

    PubMed Central

    Deddish, P A; Wang, J; Michel, B; Morris, P W; Davidson, N O; Skidgel, R A; Erdös, E G

    1994-01-01

    Angiotensin I-converting enzyme (ACE, kininase II) is a single-chain protein containing two active site domains (named N- and C-domains according to position in the chain). ACE is bound to plasma membranes by its C-terminal hydrophobic transmembrane anchor. Ileal fluid, rich in ACE activity, obtained from patients after surgical colectomy was used as the source. Column chromatography, including modified affinity chromatography on lisinopril-Sepharose, yielded homogeneous ACE after only a 45-fold purification. N-terminal sequencing of ileal ACE and partial sequencing of CNBr fragments revealed the presence of an intact N terminus but only a single N-domain active site, ending between residues 443 and 559. Thus, ileal-fluid ACE is a unique enzyme differing from the widely distributed two-domain somatic enzyme or the single C-domain testicular (germinal) ACE. The molecular mass of ileal ACE is 108 kDa and when deglycosylated, the molecular mass is 68 kDa, indicating extensive glycosylation (37% by weight). In agreement with the results reported with recombinant variants of ACE, the ileal enzyme is less Cl(-)-dependent than somatic ACE; release of the C-terminal dipeptide from a peptide substrate was optimal in only 10 mM Cl-. In addition to hydrolyzing at the C-terminal end of peptides, ileal ACE efficiently cleaved the protected N-terminal tripeptide from the luteinizing hormone-releasing hormone and its congener 6-31 times faster, depending on the Cl- concentration, than the C-domain in recombinant testicular ACE. Thus we have isolated an active human ACE consisting of a single N-domain. We suggest that there is a bridge section of about 100 amino acids between the active N- and C-domains of somatic ACE where it may be proteolytically cleaved to liberate the active N-domain. These findings have potential relevance and importance in the therapeutic application of ACE inhibitors. PMID:8052664

  10. Screening of Zulu medicinal plants for angiotensin converting enzyme (ACE) inhibitors.

    PubMed

    Duncan, A C; Jäger, A K; van Staden, J

    1999-12-15

    Twenty plants used by traditional healers in South Africa for the treatment of high blood pressure were investigated for their anti-hypertensive properties, utilizing the angiotensin converting enzyme assay. A hit rate of 65% was achieved, with the highest inhibition (97%) obtained by Adenopodia spicata leaves. A further seven plants exhibited an inhibition greater than 70% and five more over 50%. The leaves of the plants showed the greatest levels of inhibition. There was little difference in the overall hit rate between ethanolic and aqueous extracts, although in most cases there was a marked difference in activity between aqueous and ethanolic extracts from the same species. Plants exhibiting inhibition levels greater than 50% were further tested for the presence of tannins in order to eliminate possible false positives. Active plants that did not contain tannins were Agapanthus africanus, Agave americana, Clausena anisata, Dietes iridioides, Mesembruanthemum spp., Stangeria eriopus and Tulbaghia violacea.

  11. Syndrome of inappropriate secretion of antidiuretic hormone associated with angiotensin-converting enzyme inhibitor administration.

    PubMed

    Murakami, Tomoaki; Horibata, Yoko; Morimoto, Yasuko; Tateno, Shigeru; Kawasoe, Yasutaka; Niwa, Koichiro

    2013-06-01

    Angiotensin-converting enzyme inhibitors (ACEI's) are an important medication in the treatment of congestive heart failure. However, ACEIs may cause harmful side effects, such as the syndrome of inappropriate secretion of antidiuretic hormone (SIADH), which is a rare but important side effect. We describe here a case of SIADH associated with ACEI administration in a 6-year-old boy with restrictive cardiomyopathy. After recovery from acute exacerbation of congestive heart failure by tolvaptan administration, an ACEI (cilazapril) was started to decrease the production of angiotensin II, which upregulates serum antidiuretic hormone secretion. The patient's heart failure symptoms worsened, including accumulation of right pleural effusion and ascites, after the initiation of ACEI administration. Cessation of ACEI administration dramatically improved his symptoms. Because it is difficult to distinguish SIADH associated with ACEI from worsening congestive heart failure, the possibility of fluid retention due to ACEI administration should always be considered when this agent is administered to patients with heart failure.

  12. Isolation and antihypertensive effect of angiotensin I-converting enzyme (ACE) inhibitory peptides from spinach Rubisco.

    PubMed

    Yang, Yanjun; Marczak, Ewa D; Yokoo, Megumi; Usui, Hachiro; Yoshikawa, Masaaki

    2003-08-13

    Four new inhibitory peptides for angiotensin I-converting enzyme (ACE), that is, MRWRD, MRW, LRIPVA, and IAYKPAG, were isolated from the pepsin-pancreatin digest of spinach Rubisco with the use of HPLC. IC(50) values of individual peptides were 2.1, 0.6, 0.38, and 4.2 microM, respectively. MRW and MRWRD had an antihypertensive effect after oral administration to spontaneously hypertensive rats. Maximal reduction occurred 2 h after oral administration of MRW, whereas MRWRD showed maximal decrease 4 h after oral administration at doses of 20 and 30 mg/kg, respectively. IAYKPAG also exerted antihypertensive activity after oral administration at the dose of 100 mg/kg, giving a maximum decrease 4 h after oral administration. IAYKP, IAY, and KP, the fragment peptides of IAYKPAG, also exerted antihypertensive activity. LRIPVA [corrected] did not show any antihypertensive effect at a dose of 100 mg/kg despite its potent ACE-inhibitory activity.

  13. Angiotensin converting enzyme over expression in myelocytes enhances the immune response

    PubMed Central

    Bernstein, Kenneth E.; Gonzalez-Villalobos, Romer A.; Giani, Jorge F.; Shah, Kandarp; Bernstein, Ellen; Janjulia, Tea; Koronyo, Yosef; Shi, Peng D.; Koronyo-Hamaoui, Maya; Fuchs, Sebastien; Shen, Xiao Z.

    2015-01-01

    Angiotensin converting enzyme (ACE) plays an important role in blood pressure control. ACE also has effects on renal function, reproduction, hematopoiesis and several aspects of the immune response. ACE 10/10 mice over express ACE in monocytic cells; macrophages from ACE 10/10 mice demonstrate increased polarization towards a proinflammatory phenotype. As a result, ACE 10/10 mice have a highly effective immune response following challenge with either melanoma, bacterial infection or Alzheimer’s disease. The ACE 10/10 mice suggest that enhanced monocytic function greatly contributes to the ability of the immune response to defend against a wide variety of antigenic and non-antigenic challenges. PMID:24633750

  14. Angiotensin-converting enzyme inhibition in myocardial infarction--Part 1: Clinical data.

    PubMed

    Huckell, V F; Bernstein, V; Cairns, J A; Crowell, R; Dagenais, G R; Higginson, L A; Isserow, S; Laramée, P; Liu, P; McCans, J L; Orchard, R C; Prewitt, R; Quinn, B P; Samson, M; Turazza, F; Warnica, J W; Wielgosz, A

    1997-02-01

    There is an increasing body of clinical trial evidence to support the use of angiotensin-converting enzyme (ACE) inhibitors in the management of patients following myocardial infarction (MI). Enthusiasm for the use of ACE inhibitors in the acute phase of MI had previously been tempered by the adverse results of an early trial. However, exciting new information is available from several large, randomized studies that has not only quelled those initial concerns but also attests to the efficacy of using this class of medication in the first 24 h after an acute MI. A Canadian National Opinion Leader Symposium was held in November 1995 to review the results of the major ACE inhibitor clinical trials and to discuss key issues and controversies surrounding their use in acute MI. The focus of this paper, the first of two parts, is on the results of the major ACE inhibitor clinical trials.

  15. Medicinal Chemistry and Therapeutic Relevance of Angiotensin-Converting Enzyme Inhibitors

    PubMed Central

    2007-01-01

    Chemical Basis of Drug Action (PHA337 and PHA447) is a required 2-semester course sequence taught to second-professional year pharmacy students at Creighton University in both the campus and distance-education pathways. The course emphasizes integration of previous content, critical thinking, and therapeutic relevance. The content and learning experiences are organized to transition the students' thinking through a constructive process that provides ample opportunities to recall and integrate previous knowledge, learn and apply new knowledge, establish a logical connection between the science and its therapeutic relevance, and finally to apply the science knowledge to predict clinical activity and clinical outcomes as can be expected in a patient. This manuscript is based on the angiotensin converting enzyme inhibitors as an illustration of how our course objectives are accomplished. PMID:19503707

  16. Distribution of angiotensin converting enzyme in sheep hypothalamus and medulla oblongata visualized by in vitro autoradiography

    SciTech Connect

    Chai, S.Y.; McKinley, M.J.; Mendelsohn, F.A.

    1987-01-01

    In vitro autoradiographic mapping of angiotensin converting enzyme (ACE) in sheep brain using the specific ACE inhibitor, /sup 125/I-351A, revealed very high densities of binding in large blood vessels and choroid plexus. In the a very high density of labelling occurred in the organum vasculosum of the lamina terminalis and median eminence and a high density in the subfornical organ and moderate density in supraoptic, suprachiasmatic, arcuate and paraventricular nuclei. All fiber tracts were unlabelled. In the medulla oblongata, a very high density of binding was detected in the area postrema and a high density in the nucleus of the solitary tract and dorsal motor nucleus of the vagus; a moderate density was found in the substantia gelatinosa of the spinal tract and the inferior olivary nucleus.

  17. Angiotensin-converting enzyme inhibitory activity of peptides derived from caprine kefir.

    PubMed

    Quirós, A; Hernández-Ledesma, B; Ramos, M; Amigo, L; Recio, I

    2005-10-01

    In this study, a potent angiotensin-converting enzyme (ACE)-inhibitory activity was found in a commercial kefir made from caprine milk. The low molecular mass peptides released from caseins during fermentation were mainly responsible for this activity. Sixteen peptides were identified by HPLC-tandem mass spectrometry. Two of these peptides, with sequences PYVRYL and LVYPFTGPIPN, showed potent ACE-inhibitory properties. The impact of gastrointestinal digestion on ACE-inhibitory activity of kefir peptides was also evaluated. Some of these peptides were resistant to the incubation with pepsin followed by hydrolysis with Corolase PP. The ACE-inhibitory activity after simulated digestion was similar to or slightly lower than unhydrolyzed peptides, except for peptide beta-casein f(47-52) (DKIHPF), which exhibited an activity 8 times greater after hydrolysis.

  18. Nicotianamine is a novel angiotensin-converting enzyme 2 inhibitor in soybean.

    PubMed

    Takahashi, Saori; Yoshiya, Taku; Yoshizawa-Kumagaye, Kumiko; Sugiyama, Toshihiro

    2015-01-01

    Angiotensin-converting enzyme 2 (ACE2) is a carboxypeptidase which is highly homologous to angiotensin-converting enzyme (ACE). ACE2 produces vasodilator peptides angiotensin 1-7 from angiotensin II. In the present study, we synthesized various internally quenched fluorogenic (IQF) substrates (fluorophore-Xaa-Pro-quencher) based on the cleavage site of angiotensin II introducing N-terminal fluorophore N-methylanthranilic acid (Nma) and C-terminal quencher N(ε)-2,4- dinitrophenyl-lysine [Lys(Dnp)]. The synthesized mixed substrates "Nma-Xaa-Pro-Lys(Dnp)" were hydrolyzed by recombinant human (rh) ACE2. The amount of each product was determined by liquid chromatography mass spectrometry (LC-MS) with fluorescence detection and it was found that Nma-His-Pro-Lys(Dnp) is the most suitable substrate for rhACE2. The K(m), k(cat), and k(cat)/K(m) values of Nma-His-Pro-Lys(Dnp) on rhACE2 were determined to be 23.3 μM, 167 s(-1), and 7.17 μM(-1) s(-1), respectively. Using the rhACE2 and the newly developed IQF substrate, we found rhACE2 inhibitory activity in soybean and isolated the active compound soybean ACE2 inhibitor (ACE2iSB). The physicochemical data on the isolated ACE2iSB were identical to those of nicotianamine. ACE2iSB strongly inhibited rhACE2 activity with an IC50 value of 84 nM. This is the first demonstration of an ACE2 inhibitor from foodstuffs.

  19. Serum Angiotensin Converting Enzyme and the Obstructive Sleep Apnea Hypopnea Syndrome

    PubMed Central

    Benjamin, John Amit; Moller, Maria; Ebden, Philip; Bartle, Ionah; Lewis, Keir E.

    2008-01-01

    Study Objectives: We wanted to see if the obstructive sleep apnea hypopnea syndrome (OSAHS) causes hypertension and endothelial dysfunction through activation of the angiotensin-converting enzyme (ACE). Methods: A cross-sectional followed by a prospective, interventional study in a sleep disordered breathing clinic in a UK Hospital. We measured baseline serum ACE activity and ACE allele frequencies in 26 consecutive (untreated) OSAHS patients, 26 consecutive Sleepy Snorers, and 26 healthy (non-sleepy) controls. The OSAHS and Sleepy Snorers had serum ACE repeated after 6 months, with the OSAHS group receiving CPAP in the interim. Results: There was no difference in baseline mean serum ACE among OSAHS (33 IU/L), sleepy snorers (36 IU/L), and healthy controls (32 IU/L), p = 0.63. There was no difference in serum ACE activity between OSAHS and sleepy snorers after 6 months (p = 0.9) and no change in serum ACE from baseline in either group. In particular, there was no change in ACE activity in the OSAHS group on an intention to treat basis or when limiting analysis was limited to only “good” CPAP users (n = 16, p = 0.68), despite significant improvements in their Epworth scores and blood pressure and normalization of the 4% dip-rate. Conclusions: Changes in serum ACE activity do not occur in OSAHS; therefore it is unlikely to be associated with the hypertension and other cardiovascular dysfunction often reported in OSAHS. Citation: Benjamin JA; Moller M; Ebden P; Bartle I; Lewis KE. Serum angiotensin converting enzyme and the obstructive sleep apnea hypopnea syndrome. J Clin Sleep Med 2008;4(4):325–331. PMID:18763423

  20. Endothelin-converting enzymes degrade α-synuclein and are reduced in dementia with Lewy bodies.

    PubMed

    Miners, J Scott; Love, Seth

    2017-02-07

    We have examined the roles of the endothelin-converting enzyme-1 and -2 (ECE-1 and ECE-2) in the homeostasis of α-synuclein (α-syn) and pathogenesis of Lewy body disease. The ECEs are named for their ability to convert inactive big endothelin to the vasoactive peptide endothelin-1 (EDN1). We have found that ECE-1 and ECE-2 cleave and degrade α-syn in vitro and siRNA-mediated knockdown of ECE-1 and ECE-2 in SH-SY5Y neuroblastoma cells significantly increased α-syn both intracellularly (within the cell lysate) (P < 0.05 for both ECE-1 and -2) and extracellularly (in the surrounding medium) (P < 0.05 for ECE-1 and P = 0.07 for ECE-2). Double immunofluorescent labelling showed co-localisation of ECE-1 and ECE-2 with α-syn within the endolysosomal system (confirmed by a proximity ligation assay). To assess the possible relevance of these findings to human Lewy body disease, we measured ECE-1 and ECE-2 levels by sandwich ELISA in post-mortem samples of cingulate cortex (a region with a predilection for Lewy body pathology) in dementia with Lewy bodies (DLB) and age-matched controls. ECE-1 (P < 0.001) and ECE-2 (P < 0.01) levels were significantly reduced in DLB and both enzymes correlated inversely with the severity of Lewy body pathology as indicated by the level of α-syn phosphorylated at Ser129 (r = -0.54, P < 0.01 for ECE-1 and r = -0.49, P < 0.05 for ECE-2). Our novel findings suggest a role for ECEs in the metabolism of α-syn that could contribute to the development and progression of DLB. This article is protected by copyright. All rights reserved.

  1. Structure based drug design of angiotensin-I converting enzyme inhibitors.

    PubMed

    Anthony, C S; Masuyer, G; Sturrock, E D; Acharya, K R

    2012-01-01

    Cardiovascular disease (CVD) is responsible for ∼27% of deaths worldwide, with 80% of these occuring in developing countries. Hypertension is one of the most important treatable factors in the prevention of CVD. Angiotensin-I converting enzyme (ACE) is a two-domain dipeptidylcarboxypeptidase that is a key regulator of blood pressure as a result of its critical role in the reninangiotensin- aldosterone and kallikrien-kinin systems. Consequently, ACE is an important drug target in the treatment of CVD. ACE is primarily known for its ability to cleave angiotensin-I to the vasoactive octapeptide angiotensin-II, but is also able to cleave a number of other substrates including the vasodilator bradykinin and N-acetyl-seryl-aspartyl-lysyl-proline (acetyl-SDKP), a physiological modulator of hematopoiesis. Numerous ACE inhibiors are available clinically, and these are generally effective in treating hypertension. However some adverse effects are associated with ACE inhibition, such as the persistent dry cough and the potentially fatal angioedema. The solution of ACE crystal structures over the last decade has facilitated rational drug design which has contributed to the development of domain-selective ACE inhibitors, the most notable of which include RXP407 (N-domain) and RXPA380 (C-domain), which in principle may herald new therapeutic approaches for ACE inhibition. Additionally, dual inhibitors to ACE and other targets such as neprilysin, endothelin converting enzyme and chymase have been developed. The success of ACE inhibitors has also led to the search for novel inhibitors in food and natural products and the structure guided screening of such libraries may well reveal a number of new ACE inhibitors.

  2. Angiotensin converting enzyme immobilized on magnetic beads as a tool for ligand fishing.

    PubMed

    de Almeida, Fernando G; Vanzolini, Kenia L; Cass, Quezia B

    2017-01-05

    Angiotensin converting enzyme (ACE) presents an important role in blood pressure regulation, since that converts angiotensin I to the vasoconstrictor angiotensin II. Some commercially available ACE inhibitors are captopril, lisinopril and enalapril; due to their side effects, naturally occurring inhibitors have been prospected. In order to endorse this research field we have developed a new tool for ACE ligand screening. To this end, ACE was extracted from bovine lung, purified and chemically immobilized in modified ferrite magnetic beads (ACE-MBs). The ACE-MBs have shown a Michaelian kinetic behavior towards hippuryl-histidyl-leucine. Moreover, as proof of concept, the ACE-MBs was inhibited by lisinopril with a half maximal inhibitory concentration (IC50) of 10nM. At the fishing assay, ACE-MBs were able not only to fish out the reference inhibitor, but also one peptide from a pool of tryptic digested BSA. In conclusion, ACE-MBs emerge as new straightforward tool for ACE kinetics determination, inhibition and binder screening.

  3. The role of angiotensin-converting enzyme polymorphism in congestive heart failure.

    PubMed

    Pilati, Mara; Cicoira, Mariantonietta; Zanolla, Luisa; Nicoletti, Ilaria; Muraglia, Simone; Zardini, Piero

    2004-01-01

    Angiotensin-converting enzyme (ACE) is a zinc metallopeptidase, with primary known functions of converting angiotensin I into the vasoactive and aldosterone-stimulating peptide angiotensin II and inactivating bradykinin. There is high variability among individuals in ACE concentrations, mainly due to the presence of a genetic polymorphism. The ACE gene has, in fact, insertion/deletion polymorphism in intron 16, consisting of a 287-base pair Alu repeat sequence, with three genotypes: insertion polymorphism, insertion/deletion polymorphism, and deletion polymorphism. The genetic effect accounts for 47% of the total variance of serum ACE. The determination of this polymorphism has allowed researchers to study the implications of the ACE gene in many case-control studies of cardiovascular disease, including myocardial infarction and hypertrophic and dilated cardiomyopathy. We review the current knowledge about the ACE gene polymorphism and its implications in heart failure secondary to ischemic or idiopathic dilated cardiomyopathy. Interpretation of the results of studies about the role of this polymorphism are controversial. The repetition of epidemio-genetic studies and the creation of adequate experimental studies will help to definitively establish the pathogenetic role of the permanent increase in ACE expression associated with the deletion polymorphism genotype.

  4. The presence of two types of prorenin converting enzymes in the mouse submandibular gland.

    PubMed

    Kim, W S; Nakayama, K; Murakami, K

    1991-11-18

    We have recently demonstrated, by protein and cDNA sequence analyses, that prorenin converting enzyme (PRECE) in the ICR mouse submandibular gland is identical to the epidermal growth factor-binding protein (EGF-BP) type B, the mGK-13 gene product identified in Balb/c mouse. However, in the course of cDNA cloning, we noticed the presence of the other cDNA type highly homologous but not identical to the PRECE cDNA. The sequence of the newly identified cDNA was identical to that of the pSGP-2 cDNA cloned from NMRI mice, which also encodes EGF-BP type B different at 9 out of 261 amino acids from the mGK-13 product. Although this difference has been explained by strain polymorphism, our results indicate that these two proteins are distinct gene products. The product of the newly identified cDNA also had a prorenin converting activity. Thus, the products of both cDNAs identified in previous and present studies are involved in maturation of two bioactive polypeptides, renin and EGF.

  5. Targeting angiotensin-converting enzyme 2 as a new therapeutic target for cardiovascular diseases.

    PubMed

    Parajuli, Nirmal; Ramprasath, Tharmarajan; Patel, Vaibhav B; Wang, Wang; Putko, Brendan; Mori, Jun; Oudit, Gavin Y

    2014-07-01

    Angiotensin-converting enzyme 2 (ACE2) is a monocarboxypeptidase that metabolizes several vasoactive peptides, including angiotensin II (Ang-II; a vasoconstrictive/proliferative peptide), which it converts to Ang-(1-7). Ang-(1-7) acts through the Mas receptor to mediate vasodilatory/antiproliferative actions. The renin-angiotensin system involving the ACE-Ang-II-Ang-II type-1 receptor (AT1R) axis is antagonized by the ACE2-Ang-(1-7)-Mas receptor axis. Loss of ACE2 enhances adverse remodeling and susceptibility to pressure and volume overload. Human recombinant ACE2 may act to suppress myocardial hypertrophy, fibrosis, inflammation, and diastolic dysfunction in heart failure patients. The ACE2-Ang-(1-7)-Mas axis may present a new therapeutic target for the treatment of heart failure patients. This review is mainly focused on the analysis of ACE2, including its influence and potentially positive effects, as well as the potential use of human recombinant ACE2 as a novel therapy for the treatment cardiovascular diseases, such as hypertension and heart failure.

  6. Mice lacking angiotensin-converting enzyme have low blood pressure, renal pathology, and reduced male fertility.

    PubMed

    Esther, C R; Howard, T E; Marino, E M; Goddard, J M; Capecchi, M R; Bernstein, K E

    1996-05-01

    Mammals produce two isozymes of angiotensin-converting enzyme (ACE). Somatic ACE plays an important role in the control of blood pressure. The function of testis ACE, produced by male and germ cells, is not known. To examine the roles of these isozymes, we used targeted homologous recombination to introduce a modified ACE allele into a mouse line. Mice homozygous for this mutant allele lack both ACE isozymes and have markedly reduced blood pressures. Contrary to a previous report, we found heterozygous male mice to have normal blood pressures. Homozygous mutant mice also have severe renal disease. The renal papilla is markedly reduced, and the intrarenal arteries exhibit vascular hyperplasia associated with a perivascular inflammatory infiltrate. These animals cannot effectively concentrate urine. They also have an abnormally low urinary sodium to potassium ratio despite reduced levels of aldosterone. Homozygous mutant male mice sire significantly smaller litters than wild-type male mice; however, no defect in sperm number, morphology, or motility was detected. ACE-deficient animals demonstrate the role of this enzyme in systemic blood pressure, renal development and function, and male fertility.

  7. Structural basis of Ac-SDKP hydrolysis by Angiotensin-I converting enzyme

    PubMed Central

    Masuyer, Geoffrey; Douglas, Ross G.; Sturrock, Edward D.; Acharya, K. Ravi

    2015-01-01

    Angiotensin-I converting enzyme (ACE) is a zinc dipeptidylcarboxypeptidase with two active domains and plays a key role in the regulation of blood pressure and electrolyte homeostasis, making it the principal target in the treatment of cardiovascular disease. More recently, the tetrapetide N-acetyl-Ser–Asp–Lys–Pro (Ac-SDKP) has emerged as a potent antifibrotic agent and negative regulator of haematopoietic stem cell differentiation which is processed exclusively by ACE. Here we provide a detailed biochemical and structural basis for the domain preference of Ac-SDKP. The high resolution crystal structures of N-domain ACE in complex with the dipeptide products of Ac-SDKP cleavage were obtained and offered a template to model the mechanism of substrate recognition of the enzyme. A comprehensive kinetic study of Ac-SDKP and domain co-operation was performed and indicated domain interactions affecting processing of the tetrapeptide substrate. Our results further illustrate the molecular basis for N-domain selectivity and should help design novel ACE inhibitors and Ac-SDKP analogues that could be used in the treatment of fibrosis disorders. PMID:26403559

  8. The Dynamic Nonprime Binding of Sampatrilat to the C-Domain of Angiotensin-Converting Enzyme.

    PubMed

    Sharma, Rajni K; Espinoza-Moraga, Marlene; Poblete, Horacio; Douglas, Ross G; Sturrock, Edward D; Caballero, Julio; Chibale, Kelly

    2016-12-27

    Sampatrilat is a vasopeptidase inhibitor that inhibits both angiotensin I-converting enzyme (ACE) and neutral endopeptidase. ACE is a zinc dipeptidyl carboxypeptidase that contains two extracellular domains (nACE and cACE). In this study the molecular basis for the selectivity of sampatrilat for nACE and cACE was investigated. Enzyme inhibition assays were performed to evaluate the in vitro ACE domain selectivity of sampatrilat. The inhibition of the C-domain (Ki = 13.8 nM) by sampatrilat was 12.4-fold more potent than that for the N-domain (171.9 nM), indicating differences in affinities for the respective ACE domain binding sites. Interestingly, replacement of the P2 group of sampatrilat with an aspartate abrogated its C-selectivity and lowered the potency of the inhibitor to activities in the micromolar range. The molecular basis for this selective profile was evaluated using molecular modeling methods. We found that the C-domain selectivity of sampatrilat is due to occupation of the lysine side chain in the S1 and S2 subsites and interactions with Glu748 and Glu1008, respectively. This study provides new insights into ligand interactions with the nonprime binding site that can be exploited for the design of domain-selective ACE inhibitors.

  9. Molecular diversity of tuliposide A-converting enzyme in the tulip.

    PubMed

    Nomura, Taiji; Tsuchigami, Aya; Ogita, Shinjiro; Kato, Yasuo

    2013-01-01

    Tuliposide A-converting enzyme (TCEA) catalyzes the conversion of 6-tuliposide A to its lactonized aglycon, tulipalin A, in the tulip (Tulipa gesneriana). The TgTCEA gene, isolated previously from petals, was transcribed in all tulip tissues but not in the bulbs despite the presence of TCEA activity, which allowed prediction of the presence of a TgTCEA isozyme gene preferentially expressed in the bulbs. Here, the TgTCEA-b gene, the TgTCEA homolog, was identified in bulbs. TgTCEA-b polypeptides showed approximately 77% identity to the petal TgTCEA. Functional characterization of the recombinant enzyme verified that TgTCEA-b encoded the TCEA. Moreover, the TgTCEA-b was found to be localized to plastids, as found for the petal TgTCEA. Transcript analysis revealed that TgTCEA-b was functionally transcribed in the bulb scales, unlike the TgTCEA gene, whose transcripts were absent there. In contrast, TgTCEA-b transcripts were in the minority in other tissues where TgTCEA transcripts were dominant, indicating a tissue preference for the transcription of those isozyme genes.

  10. Endothelin-converting enzyme-1 (ECE-1) is post-transcriptionally regulated by alternative polyadenylation.

    PubMed

    Whyteside, Alison R; Turner, Anthony J; Lambert, Daniel W

    2014-01-01

    Endothelin-converting enzyme-1 (ECE-1) is the enzyme predominantly responsible for producing active endothelin-1 (ET-1), a mitogenic peptide implicated in the aetiology of a number of diseases, including cancer. Elevated levels of ECE-1 have been observed in a range of malignancies, with high expression conferring poor prognosis and aiding the acquisition of androgen independence in prostate cancer. The mechanisms regulating the expression of ECE-1 in cancer cells are poorly understood, hampering the development of novel therapies targeting the endothelin axis. Here we provide evidence that the expression of ECE-1 is markedly inhibited by its 3'UTR, and that alternative polyadenylation (APA) results in the production of ECE-1 transcripts with truncated 3'UTRs which promote elevated protein expression. Abolition of the ECE-1 APA sites reduced protein expression from a reporter vector in prostate cancer cells, suggesting these sites are functional. This is the first study to identify ECE-1 as a target for APA, a regulatory mechanism aberrantly activated in cancer cells, and provides novel information about the mechanisms leading to ECE-1 overexpression in malignant cells.

  11. Abalone Protein Hydrolysates: Preparation, Angiotensin I Converting Enzyme Inhibition and Cellular Antioxidant Activity

    PubMed Central

    Park, Soo Yeon; Je, Jae-Young; Hwang, Joung-Youl; Ahn, Chang-Bum

    2015-01-01

    Abalone protein was hydrolyzed by enzymatic hydrolysis and the optimal enzyme/substrate (E/S) ratios were determined. Abalone protein hydrolysates (APH) produced by Protamex at E/S ratio of 1:100 showed angiotensin I converting enzyme inhibitory activity with IC50 of 0.46 mg/mL, and APH obtained by Flavourzyme at E/S ratio of 1:100 possessed the oxygen radical absorbance capacity value of 457.6 μM trolox equivalent/mg sample. Flavourzyme abalone protein hydrolysates (FAPH) also exhibited H2O2 scavenging activity with IC50 of 0.48 mg/mL and Fe2+ chelating activity with IC50 of 2.26 mg/mL as well as high reducing power. FAPH significantly (P<0.05) protected H2O2-induced hepatic cell damage in cultured hepatocytes, and the cell viability was restored to 90.27% in the presence of FAPH. FAPH exhibited 46.20% intracellular ROS scavenging activity and 57.89% lipid peroxidation inhibition activity in cultured hepatocytes. Overall, APH may be useful as an ingredient for functional foods. PMID:26451354

  12. Radiation damage to the lung: mitigation by angiotensin converting enzyme (ACE) inhibitors

    PubMed Central

    Medhora, Meetha; Gao, Feng; Jacobs, Elizabeth R.; Moulder, John E.

    2011-01-01

    Concern regarding accidental overexposure to radiation has been raised after the devastating Tohuku earthquake and tsunami which initiated the Fukushima Daiichi nuclear disaster in Japan, in March 2011. Radiation exposure is toxic and can be fatal depending on the dose received. Injury to the lung is often reported as part of multi-organ failure in victims of accidental exposures. Doses of radiation >8 Gray to the chest can induce pneumonitis with right ventricular hypertrophy starting after ~2 months. Higher doses may be followed by pulmonary fibrosis that presents months to years after exposure. Though the exact mechanisms of radiation lung damage are not known, experimental animal models have been widely used to study this injury. Rodent models for pneumonitis and fibrosis exhibit vascular, parenchymal and pleural injuries to the lung. Inflammation is a part of the injuries suggesting involvement of the immune system. Researchers world-wide have tested a number of interventions to prevent or mitigate radiation lung injury. One of the first and most successful class of mitigators are inhibitors of angiotensin converting enzyme (ACE), an enzyme that is abundant in the lung. These results offer hope that lung injury from radiation accidents may be mitigated, since the ACE inhibitor captopril was effective when started up to one week after irradiation. PMID:22023053

  13. Association of angiotensin-converting enzyme, CYP46A1 genes polymorphism with senile cataract

    PubMed Central

    Raza, Syed Tasleem; Abbas, Shania; Chandra, Anu; Singh, Luxmi; Rizvi, Saliha; Mahdi, Farzana

    2017-01-01

    Background: Senile cataract is the most common type of cataract characterized by gradual progressive thickening of the lens of the eye. Previously, many studies investigated the association between genetic polymorphism and senile cataract. Angiotensin-converting enzyme (ACE) I/D polymorphism is the potential risk factor for many eye-related diseases such as retinopathy and glaucoma. CYP46A1 enzyme converts cholesterol to 24S-hydroxycholesterol; human lens' membranes contain the highest cholesterol content. Defects in enzymes of cholesterol metabolism can be associated with cataracts. Hence, the present study was carried out to investigate the association of ACE and CYP46A1 genes polymorphism with senile cataract cases and controls. Materials and Methods: ACE (rs 4646994) and CYP46A1 (rs 754203) genes polymorphism in cases and controls were evaluated by polymerase chain reaction and restriction fragment length polymorphism. Results: This study included 103 senile cataract cases (55 were males and 48 were females) and 102 controls (53 were males and 49 were females). Mean age of cases in this study was 52.02 ± 12.11 years while in control group 53.74 ± 11.87 years. Frequencies of ACE ID, DD, and II genotypes in senile cataract cases were 64.07%, 4.85%, and 31.06% and controls were 61.76%, 26.47%, and 11.76%, respectively. The CYP46A1 gene CT, CC, and TT genotype frequencies were 48.54%, 8.73%, and 42.71% in senile cataract cases and 28.43%, 3.92%, and 67.64% in healthy controls, respectively. ACE DD and II genotypes (P < 0.001,P = 0.0008) and CYP46A1 CT and TT genotypes (P = 0.003,P = 0.0003) were significantly associated with senile cataract cases compared to the controls. Conclusion: Findings of this study suggest that ACE and CYP46A1 genes polymorphism may be a predictive marker for early identification of population at risk of senile cataract. This potential role of ACE and CYP46A1 genes polymorphism as a marker of susceptibility to senile cataract needs

  14. Role of angiotensin-converting enzyme 2 (ACE2) in diabetic cardiovascular complications.

    PubMed

    Patel, Vaibhav B; Parajuli, Nirmal; Oudit, Gavin Y

    2014-04-01

    Diabetes mellitus results in severe cardiovascular complications, and heart disease and failure remain the major causes of death in patients with diabetes. Given the increasing global tide of obesity and diabetes, the clinical burden of diabetes-induced cardiovascular disease is reaching epidemic proportions. Therefore urgent actions are needed to stem the tide of diabetes which entails new prevention and treatment tools. Clinical and pharmacological studies have demonstrated that AngII (angiotensin II), the major effector peptide of the RAS (renin-angiotensin system), is a critical promoter of insulin resistance and diabetes mellitus. The role of RAS and AngII has been implicated in the progression of diabetic cardiovascular complications and AT1R (AngII type 1 receptor) blockers and ACE (angiotensin-converting enzyme) inhibitors have shown clinical benefits. ACE2, the recently discovered homologue of ACE, is a monocarboxypeptidase which converts AngII into Ang-(1-7) [angiotensin-(1-7)] which, by virtue of its actions on the MasR (Mas receptor), opposes the effects of AngII. In animal models of diabetes, an early increase in ACE2 expression and activity occurs, whereas ACE2 mRNA and protein levels have been found to decrease in older STZ (streptozotocin)-induced diabetic rats. Using the Akita mouse model of Type 1 diabetes, we have recently shown that loss of ACE2 disrupts the balance of the RAS in a diabetic state and leads to AngII/AT1R-dependent systolic dysfunction and impaired vascular function. In the present review, we will discuss the role of the RAS in the pathophysiology and treatment of diabetes and its complications with particular emphasis on potential benefits of the ACE2/Ang-(1-7)/MasR axis activation.

  15. Tubuloglomerular Feedback and Single Nephron Function after Converting Enzyme Inhibition in the Rat

    PubMed Central

    Ploth, David W.; Rudulph, James; Lagrange, Ronald; Navar, L. Gabriel

    1979-01-01

    Experiments were done in normal rats to assess kidney, single nephron, and tubuloglomerular feedback responses during renin-angiotensin blockade with the converting enzyme inhibitor (CEI) SQ 20881 (E. R. Squibb & Sons, Princeton, N. Y.) (3 mg/kg, per h). Converting enzyme inhibition was documented by complete blockade of vascular responses to infusions of angiotensin I (600 ng/kg). Control plasma renin activity was 12.5±2.7 ng angiotensin I/ml per h (mean±SEM) and increased sevenfold with CEI (n = 7). There were parallel increases in glomerular filtration rate from 1.08±0.05 to 1.26±0.05 ml/min and renal blood flow from 6.7±0.4 to 7.5±0.5 ml/min. During CEI infusion absolute and fractional sodium excretion were increased 10-fold. Proximal tubule and peritubular capillary pressures were unchanged. Single nephron glomerular filtration rate (SNGFR) was measured from both proximal and distal tubule collections; SNGFR based only on distal collections was significantly increased by CEI. A significant difference was observed between SNGFR values measured from proximal and distal tubule sites (6.0±1.6 nl/min) and this difference remained unchanged after CEI administration. Slight decreases in fractional absorption were suggested at micropuncture sites beyond the late proximal tubule, whereas early distal tubule flow rate was augmented by CEI. Tubuloglomerular feedback activity was assessed by measuring changes in proximal tubule stop-flow pressure (SFP) or SNGFR in response to alterations in orthograde microperfusion rate from late proximal tubule sites. During control periods, SFP was decreased 11.2±0.4 mm Hg when the perfusion rate was increased to 40 nl/min; during infusion of CEI, the same increase in perfusion rate resulted in a SFP decrement of 6.7±0.5 mm Hg (P<.001). When late proximal tubule perfusion rate was increased from 0 to 30 nl/min, SNGFR was decreased by 15.0±1.2 nl/min during control conditions, and by 11.3±1.3 nl/min during CEI infusion

  16. Novel internally quenched fluorogenic substrates for angiotensin I-converting enzyme and carboxypeptidase Y.

    PubMed

    Takahashi, Saori; Ono, Hiroki; Gotoh, Takeshi; Yoshizawa-Kumagaye, Kumiko; Sugiyama, Toshihiro

    2011-12-01

    Angiotensin I-converting enzyme (ACE, EC 3.4.15.1) is one of the most important enzymes in the renin-angiotensin system, a major blood pressure control system in mammals. We synthesized novel internally quenched fluorogenic (IQF) substrates for ACE based on the cleavage site of an angiotensin I, introducing N-methyl anthranic acid (Nma) and N(ε)-2,4-dinitrophenyl-lysine (Lys(Dnp))at the N- and C-terminal regions. Kinetic parameters of the synthesized IQF substrates Nma-Phe-His-Lys(Dnp) and Nma-His-Pro-Phe-Lys(Dnp)-Pro were compared with those of a common peptide substrate for ACE, hippuryl (Hip)-His-Leu. The k(cat)/K(m) values of Nma-Phe-His-Lys(Dnp), Nma-His-Pro-Phe-Lys(Dnp)-Pro, and Hip-His-Leu were 5.12, 1.90, and 0.80 µM(-1) s(-1) for rabbit lung ACE, and 16.0, 7.36, and 0.30 µM(-1) s(-1) for recombinant human (rh)-ACE, respectively. These results indicate that Nma-Phe-His-Lys(Dnp) is an excellent substrate for rh-ACE. Carboxypeptidase Y also hydrolyzed Nma-Phe-His-Lys(Dnp) efficiently with K(m), k(cat), and k(cat)/K(m) values of 60.2 µM, 105 s(-1), and 1.74 µM(-1) s(-1), respectively. On the other hand, carboxypeptidase B did not hydrolyze IQF substrates. The newly developed IQF substrate, Nma-Phe-His-Lys(Dnp), is a valuable tool for ACE and carboxypeptidase studies.

  17. Inhibition of interleukin 1β converting enzyme family proteases reduces ischemic and excitotoxic neuronal damage

    PubMed Central

    Hara, Hideaki; Friedlander, Robert M.; Gagliardini, Valeria; Ayata, Cenk; Fink, Klaus; Huang, Zhihong; Shimizu-Sasamata, Masao; Yuan, Junying; Moskowitz, Michael A.

    1997-01-01

    The interleukin 1β converting enzyme (ICE) family plays a pivotal role in programmed cell death and has been implicated in stroke and neurodegenerative diseases. During reperfusion after filamentous middle cerebral artery occlusion, ICE-like cleavage products and tissue immunoreactive interleukin 1β (IL-1β) levels increased in ischemic mouse brain. Ischemic injury decreased after intracerebroventricular injections of ICE-like protease inhibitors, N-benzyloxycarbonyl-Val-Ala-Asp-fluoromethylketone (z-VAD.FMK), acetyl-Tyr-Val-Ala-Asp-chloromethylketone, or a relatively selective inhibitor of CPP32-like caspases, N-benzyloxycarbonyl-Asp-Glu-Val-Asp-fluoromethylketone, but not a cathepsin B inhibitor, N-benzyloxycarbonyl-Phe-Ala-fluoromethylketone. z-VAD.FMK decreased ICE-like cleavage products and tissue immunoreactive IL-1β levels in ischemic mouse brain and reduced tissue damage when administered to rats as well. Only z-VAD.FMK and acetyl-Tyr-Val-Ala-Asp-chloromethylketone reduced brain swelling, and N-benzyloxycarbonyl-Asp-Glu-Val-Asp-fluoromethylketone did not attenuate the ischemia-induced increase in tissue IL-1β levels. The three cysteine protease inhibitors significantly improved behavioral deficits, thereby showing that functional recovery of ischemic neuronal tissue can follow blockade of enzymes associated with apoptotic cell death. Finally, we examined the effect of z-VAD.FMK on excitotoxicity and found that it protected against α-amino-3-hydroxy-5-methyl-4-isoxazole propionate-induced or to a lesser extent N-methyl-d-aspartate-induced excitotoxic brain damage. Thus, ICE-like and CPP32-like caspases contribute to mechanisms of cell death in ischemic and excitotoxic brain injury and provide therapeutic targets for stroke and neurodegenerative brain damage. PMID:9050895

  18. Functional analysis of the human somatic angiotensin I-converting enzyme gene promoter.

    PubMed

    Testut, P; Soubrier, F; Corvol, P; Hubert, C

    1993-08-01

    Angiotensin I-converting enzyme (ACE) is a key enzyme in the regulation of systemic blood pressure and plays a major role in the renin-angiotensin and bradykinin-kinin systems, at the luminal surface of the vascular endothelia. To identify the promoter region, the transcription regulatory elements and the cell specificity of the ACE gene, five successive DNA deletions of the 5' upstream region (-1214, -754, -472, -343, -132 bp relative to the start site of transcription) were isolated and fused in sense and antisense orientations to the bacterial chloramphenicol acetyltransferase (CAT) reporter gene in the promoterless plasmid pBLCAT3. Promoter activities were measured in transient transfection assays using three different cell lines from rabbit endothelium (RE), human embryocarcinoma (Tera-1) and hepatocarcinoma cells (HepG2). All five fragments of the ACE promoter region directed expression of the CAT gene when transfected into the endothelial and the embryocarcinoma cells, which contain endogenous ACE mRNA and express ACE activity. In contrast only minimal levels of promoter activity were obtained on transfection into hepatocarcinoma cells in which endogenous ACE mRNA and ACE activity were not detected. Transfection of RE and Tera-1 cells demonstrated that promoter activity was defined by the length of the ACE promoter sequence inserted into the construct. The 132 bases located upstream from the transcription start site were sufficient to confer ACE promoter activity, whereas the sequences upstream from -472 bp and between -343 bp and -132 bp were responsible for a decrease of promoter activity. Furthermore, the minimal 132 bp of the ACE promoter contains elements which direct cell-specific CAT expression. In addition, the DNA transfection study in the presence of dexamethasone suggested that the potential glucocorticoid regulatory elements, located in the sequence of the ACE promoter, are not functional.

  19. Functional analysis of the human somatic angiotensin I-converting enzyme gene promoter.

    PubMed Central

    Testut, P; Soubrier, F; Corvol, P; Hubert, C

    1993-01-01

    Angiotensin I-converting enzyme (ACE) is a key enzyme in the regulation of systemic blood pressure and plays a major role in the renin-angiotensin and bradykinin-kinin systems, at the luminal surface of the vascular endothelia. To identify the promoter region, the transcription regulatory elements and the cell specificity of the ACE gene, five successive DNA deletions of the 5' upstream region (-1214, -754, -472, -343, -132 bp relative to the start site of transcription) were isolated and fused in sense and antisense orientations to the bacterial chloramphenicol acetyltransferase (CAT) reporter gene in the promoterless plasmid pBLCAT3. Promoter activities were measured in transient transfection assays using three different cell lines from rabbit endothelium (RE), human embryocarcinoma (Tera-1) and hepatocarcinoma cells (HepG2). All five fragments of the ACE promoter region directed expression of the CAT gene when transfected into the endothelial and the embryocarcinoma cells, which contain endogenous ACE mRNA and express ACE activity. In contrast only minimal levels of promoter activity were obtained on transfection into hepatocarcinoma cells in which endogenous ACE mRNA and ACE activity were not detected. Transfection of RE and Tera-1 cells demonstrated that promoter activity was defined by the length of the ACE promoter sequence inserted into the construct. The 132 bases located upstream from the transcription start site were sufficient to confer ACE promoter activity, whereas the sequences upstream from -472 bp and between -343 bp and -132 bp were responsible for a decrease of promoter activity. Furthermore, the minimal 132 bp of the ACE promoter contains elements which direct cell-specific CAT expression. In addition, the DNA transfection study in the presence of dexamethasone suggested that the potential glucocorticoid regulatory elements, located in the sequence of the ACE promoter, are not functional. Images Figure 1 Figure 3 PMID:8394696

  20. Applicability of green fluorescence protein in the study of endothelin converting enzyme-1c trafficking.

    PubMed

    Kuruppu, Sanjaya; Tochon-Danguy, Nathalie; Smith, A Ian

    2013-03-01

    Endothelin-1 (ET-1) is one of the most potent peptide vasoconstrictors known. It is produced upon the cleavage of its precursor big endothelin-1 by endothelin converting enzyme-1 (ECE-1). Production of ET-1 is thought to be dependent upon the expression of ECE-1 at the cell surface. Therefore, mechanisms inducing the trafficking of ECE-1 to the cell surface have been the focus of recent research. This research has identified phosphorylation of the cytoplasmic region of ECE-1 as a main cellular signal inducing its trafficking to the cell surface. Previous studies have used green fluorescent protein (GFP) tagged ECE-1 to monitor phosphorylation induced trafficking of ECE-1 to the cell surface. However, it has been speculated that the addition of the GFP tag can itself alter enzyme activity and phosphorylation of ECE-1, and hence the suitability of GFP or any other protein tag in studying ECE-1 distribution and trafficking. ECE-1c is the most widely expressed isoform in endothelial cells. We therefore expressed ECE-1c with a GFP tag either at the N or C-terminus of ECE-1c. Catalytic activity and effect on protein kinase C (PKC) induced phosphorylation was compared between the two chimeras and wild-type ECE-1c. Our results indicate that positioning of the GFP tag on the C-terminus abrogates activity without effecting PKC-induced phosphorylation. However, GFP tag on the N-terminus has the opposite effect. Results of this study shed light on the applicability of GFP or perhaps other protein tags in studying ECE-1c distribution and trafficking.

  1. Regulation of endothelin-converting enzyme-1 (ECE-1) by the calcimimetic R-568.

    PubMed

    Martínez-Miguel, Patricia; Medrano-Andrés, Diana; Lopes-Martín, Vanessa; Arribas-Gómez, Ignacio; Rodríguez-Puyol, Manuel; Rodríguez-Puyol, Diego; López-Ongil, Susana

    2013-10-01

    Although calcimimetics were developed to block parathyroid hormone synthesis, some reports suggest that they may also reduce blood pressure by unknown mechanisms. Calcimimetic-induced changes in the synthesis of endothelial vasoactive factors could be involved. Wistar rats were treated with the calcimimetic R-568, and systolic blood pressure (SBP) was registered with a tail-cuff sphygmomanometer, the content of endothelial nitric oxide synthase (eNOS) and endothelin-converting enzyme (ECE-1) in tissue was evaluated by immunohistochemistry and Western blot, circulating levels of endothelin-1 (ET-1) were measured by ELISA. R-568 reduced SBP and circulating levels of ET-1, without changes in eNOS expression. In contrast, R-568 increased the lung and vascular content of ECE-1. In order to analyze the mechanisms involved, we studied the effect of R-568 on human endothelial cells. R-568 did not modify neither eNOS protein content nor pre-pro-ET-1 mRNA expression, but increased ECE-1 protein content, and decreased ET-1 synthesis and ECE-1 activity. The inhibition of ECE-1 activity was very strong, similar to the classic ECE inhibitor phosphoramidon, the addition of exogenous zinc restored enzymatic activity. Moreover, the amount of zinc in immunoprecipitated ECE from R-568 treated cells was 3-fold less than in control cells. In conclusion, R-568 inhibits ECE by expelling zinc from the enzyme, with the subsequent decrease in enzymatic activity and reducing circulating levels of ET-1, which may be responsible for the lower SBP observed in R-568-treated rats. This descent would be partially compensated by the increased synthesis of the ECE-1 itself, and by other homeostatic mechanisms that regulate SBP.

  2. Design, synthesis and biological activity of novel non-peptidyl endothelin converting enzyme inhibitors, 1-phenyl-tetrazole-formazan analogues.

    PubMed

    Yamazaki, Kazuto; Hasegawa, Hirohiko; Umekawa, Kayo; Ueki, Yasuyuki; Ohashi, Naohito; Kanaoka, Masaharu

    2002-05-06

    A novel non-peptidyl endothelin converting enzyme inhibitor was obtained through a pharmacophore analysis of known inhibitors and three-dimensional structure database search. Analogues of the new inhibitor were designed using the structure-activity relationship of known inhibitors and synthesized. In anesthetized rats, intraperitoneal administration of the analogues suppressed the pressor responses induced by big endothelin-1.

  3. A novel aggregation-induced emission based fluorescent probe for an angiotensin converting enzyme (ACE) assay and inhibitor screening.

    PubMed

    Wang, Haibo; Huang, Yi; Zhao, Xiaoping; Gong, Wan; Wang, Yi; Cheng, Yiyu

    2014-12-11

    A 'turn-on' fluorescent probe based on aggregation-induced emission (AIE) has been developed. It exhibits excellent selectivity and sensitivity for monitoring angiotensin converting enzyme (ACE) activity both in solutions and in living cells as well as for screening ACE inhibitors in vitro.

  4. Angiotensin I-converting enzyme inhibitor derived from cross-linked oyster protein.

    PubMed

    Xie, Cheng-Liang; Kim, Jin-Soo; Ha, Jong-Myung; Choung, Se-Young; Choi, Yeung-Joon

    2014-01-01

    Following cross-linking by microbial transglutaminase, modified oyster proteins were hydrolyzed to improve inhibitory activity against angiotensin-converting enzyme (ACE) inhibitory activity with the use of a single protease, or a combination of six proteases. The oyster hydrolysate with the lowest 50% ACE inhibitory concentration (IC50) of 0.40 mg/mL was obtained by two-step hydrolysis of the cross-linked oyster protein using Protamex and Neutrase. Five ACE inhibitory peptides were purified from the oyster hydrolysate using a multistep chromatographic procedure comprised of ion-exchange, size exclusion, and reversed-phase liquid chromatography. Their sequences were identified as TAY, VK, KY, FYN, and YA, using automated Edman degradation and mass spectrometry. These peptides were synthesized, and their IC50 values were measured to be 16.7, 29.0, 51.5, 68.2, and 93.9 μM, respectively. Toxicity of the peptides on the HepG2 cell line was not detected. The oyster hydrolysate also significantly decreased the systolic blood pressure of spontaneously hypertensive rats (SHR). The antihypertensive effect of the oyster hydrolysate on SHR was rapid and long-lasting, compared to commercially obtained sardine hydrolysate. These results suggest that the oyster hydrolysate could be a source of effective nutraceuticals against hypertension.

  5. Harnessing the natural inhibitory domain to control TNFα Converting Enzyme (TACE) activity in vivo

    PubMed Central

    Wong, Eitan; Cohen, Tal; Romi, Erez; Levin, Maxim; Peleg, Yoav; Arad, Uri; Yaron, Avraham; Milla, Marcos E.; Sagi, Irit

    2016-01-01

    Dysregulated activity of A Disintegrin And Metalloproteinase 17 (ADAM17)/TNFα Converting Enzyme (TACE) is associated with inflammatory disorders and cancer progression by releasing regulatory membrane-tethered proteins like TNFα, IL6R and EGFR ligands. Although specific inhibition of TACE is thought to be a viable strategy for inflammatory disorders and for malignancies treatment, the generation of effective inhibitors in vivo has been proven to be challenging. Here we report on the development of a protein inhibitor that leverages the endogenous modulator of TACE. We have generated a stable form of the auto-inhibitory TACE prodomain (TPD), which specifically inhibits in vitro and cell-surface TACE, but not the related ADAM10, and effectively modulated TNFα secretion in cells. TPD significantly attenuated TACE-mediated disease models of sepsis, rheumatoid arthritis (RA) and inflammatory bowel disease (IBD), and reduced TNFα in synovial fluids from RA patients. Our results demonstrate that intervening with endogenous ADAM sheddase modulatory mechanisms holds potential as a general strategy for the design of ADAM inhibitors. PMID:27982031

  6. Converting enzyme inhibition and the glomerular hemodynamic response to glycine in diabetic rats.

    PubMed

    Slomowitz, L A; Peterson, O W; Thomson, S C

    1999-07-01

    GFR normally increases during glycine infusion. This response is absent in humans and rats with established diabetes mellitus. In diabetic patients, angiotensin-converting enzyme inhibition (ACEI) restores the effect of glycine on GFR. To ascertain the glomerular hemodynamic basis for this effect of ACEI, micropuncture studies were performed in male Wistar-Froemter rats after 5 to 6 wk of insulin-treated streptozotocin diabetes. The determinants of single-nephron GFR (SNGFR) were assessed in each rat before and during glycine infusion. Studies were performed in diabetics, diabetics after 5 d of ACEI (enalapril in the drinking water), and weight-matched controls. Diabetic rats manifest renal hypertrophy and glomerular hyperfiltration but not glomerular capillary hypertension. ACEI reduced glomerular capillary pressure, increased glomerular ultrafiltration coefficient, and did not mitigate hyperfiltration. In controls, glycine increased SNGFR by 30% due to increased nephron plasma flow. In diabetics, glycine had no effect on any determinant of SNGFR. In ACEI-treated diabetics, the SNGFR response to glycine was indistinguishable from nondiabetics, but the effect of glycine was mediated by greater ultrafiltration pressure rather than by greater plasma flow. These findings demonstrate that: (1) The absent response to glycine in established diabetes does not indicate that renal functional reserve is exhausted by hyperfiltration; and (2) ACEI restores the GFR response to glycine in established diabetes, but this response is mediated by increased ultrafiltration pressure rather than by increased nephron plasma flow.

  7. Crystal structure of the human angiotensin-converting enzyme-lisinopril complex.

    PubMed

    Natesh, Ramanathan; Schwager, Sylva L U; Sturrock, Edward D; Acharya, K Ravi

    2003-01-30

    Angiotensin-converting enzyme (ACE) has a critical role in cardiovascular function by cleaving the carboxy terminal His-Leu dipeptide from angiotensin I to produce a potent vasopressor octapeptide, angiotensin II. Inhibitors of ACE are a first line of therapy for hypertension, heart failure, myocardial infarction and diabetic nephropathy. Notably, these inhibitors were developed without knowledge of the structure of human ACE, but were instead designed on the basis of an assumed mechanistic homology with carboxypeptidase A. Here we present the X-ray structure of human testicular ACE and its complex with one of the most widely used inhibitors, lisinopril (N2-[(S)-1-carboxy-3-phenylpropyl]-L-lysyl-L-proline; also known as Prinivil or Zestril), at 2.0 A resolution. Analysis of the three-dimensional structure of ACE shows that it bears little similarity to that of carboxypeptidase A, but instead resembles neurolysin and Pyrococcus furiosus carboxypeptidase--zinc metallopeptidases with no detectable sequence similarity to ACE. The structure provides an opportunity to design domain-selective ACE inhibitors that may exhibit new pharmacological profiles.

  8. Chebulin: Terminalia chebula Retz. fruit-derived peptide with angiotensin-I-converting enzyme inhibitory activity.

    PubMed

    Sornwatana, Thakorn; Bangphoomi, Kunan; Roytrakul, Sittiruk; Wetprasit, Nuanchawee; Choowongkomon, Kiattawee; Ratanapo, Sunanta

    2015-01-01

    Angiotensin-I-converting enzyme (ACE) plays an important role in blood pressure regulation. In this study, an ACE-hexapeptide inhibitor (Asp-Glu-Asn-Ser-Lys-Phe) designated as chebulin was produced from the fruit protein of Terminalia chebula Retz. by pepsin digestion, ultrafiltrated through a 3 KDa cut-off membrane, a reverse-phase high-performance liquid chromatography, and nano-liquid chromatography tandem mass spectrometry analysis. Chebulin was found to inhibit ACE in a noncompetitive manner, as supported by the structural model. It bounds to ACE by the hydrogen bond, hydrophobic and ionic interactions via the interactions of C-terminal Phe (Phe-6), and N-terminal residues (Asp-1 and Glu-2) with the amino acid residues on noncatalytic sites of the ACE. The results showed that chebulin derived from fruits of T. chebula Retz. is a potential ACE-peptide inhibitor that could be used as a functional food additive for the prevention of hypertension and as an alternative to ACE inhibitor drug.

  9. Molecular characterization of the gene for human interleukin-1[beta] converting enzyme (IL1BC)

    SciTech Connect

    Cerretti, D.P.; Hollingsworth, L.T.; Kozlosky, C.J.; Nelson, N. ); Valentine, M.B. ); Shapiro, D.N.; Morris, S.W. Univ. of Tennessee College of Medicine, Memphis, TN )

    1994-04-01

    Interleukin-1[beta] (IL-1[beta]) mediates a wide range of immune and inflammatory responses. The active cytokine is generated by proteolytic cleavage of an inactive precursor by a protease called the IL-1[beta] converting enzyme (ICE). A cDNA encoding this protease was recently isolated. A human genomic clone containing the ICE gene (IL1BC) was isolated using the cDNA as a probe. The gene consists of 10 exons spanning at least 10.6 kb. 5[prime]-anchored polymerase chain reaction indicated a single transcription start site [approximately]33 bp upstream of the initiator Met codon. The 5[prime]-flanking region does not have an apparent TATA box but may contain an initiator (Inr) promotor element. However, transcriptional activity could not be detected with a fusion gene containing the 5[prime]-flanking region linked to the bacterial chloramphenicol acetyltransferase gene (CAT) when transfected into the human acute monocytic leukemia cell line THP-1. Using the genomic IL1BC clone, the authors have confirmed the localization of the gene to chromosome 11 band q22.2-q22.3 by fluorescence in situ hybridization. 34 refs., 2 figs., 1 tab.

  10. Accumulation and identification of angiotensin-converting enzyme inhibitory peptides from wheat germ.

    PubMed

    Yang, Runqiang; Zou, Yu; Yu, Nanjing; Gu, Zhenxin

    2011-04-27

    The incubation conditions of wheat germ for angiotensin I-converting enzyme inhibitory activity (ACEI) elevation and peptide accumulation were investigated, and five ACE inhibitory peptides were obtained. The effect of individual factors such as incubation time, temperature, initial pH, and liquid to solid ratio on ACEI and peptide concentration of incubation medium was evaluated, respectively. The combinations of four factors were further optimized using a Box-Behnken design. Under the best incubation condition (pH 4.4 with a liquid to solid ratio 8.14 mL/g at temperature 47 °C, for 7 h), maximum ACEI (92.16%) and peptide concentration (88.12 mg/g) were obtained, which were 6.2- and 2.4-fold, respectively, as compared to the unincubated wheat germ. After they were purified, five ACE inhibitory peptides, VEV, W, NPPSV, QV, and AMY, were identified by liquid chromatography/tandem mass spectrometry. The IC(50) were 115.20, 94.87, 40.56, 26.82, and 5.86 μM, respectively.

  11. Angiotensin-converting enzyme 2 protects from lethal avian influenza A H5N1 infections.

    PubMed

    Zou, Zhen; Yan, Yiwu; Shu, Yuelong; Gao, Rongbao; Sun, Yang; Li, Xiao; Ju, Xiangwu; Liang, Zhu; Liu, Qiang; Zhao, Yan; Guo, Feng; Bai, Tian; Han, Zongsheng; Zhu, Jindong; Zhou, Huandi; Huang, Fengming; Li, Chang; Lu, Huijun; Li, Ning; Li, Dangsheng; Jin, Ningyi; Penninger, Josef M; Jiang, Chengyu

    2014-05-06

    The potential for avian influenza H5N1 outbreaks has increased in recent years. Thus, it is paramount to develop novel strategies to alleviate death rates. Here we show that avian influenza A H5N1-infected patients exhibit markedly increased serum levels of angiotensin II. High serum levels of angiotensin II appear to be linked to the severity and lethality of infection, at least in some patients. In experimental mouse models, infection with highly pathogenic avian influenza A H5N1 virus results in downregulation of angiotensin-converting enzyme 2 (ACE2) expression in the lung and increased serum angiotensin II levels. Genetic inactivation of ACE2 causes severe lung injury in H5N1-challenged mice, confirming a role of ACE2 in H5N1-induced lung pathologies. Administration of recombinant human ACE2 ameliorates avian influenza H5N1 virus-induced lung injury in mice. Our data link H5N1 virus-induced acute lung failure to ACE2 and provide a potential treatment strategy to address future flu pandemics.

  12. [Corticosteroid hormones and angiotensin-converting enzyme in the dynamics of chronic granulomatous inflammation].

    PubMed

    Cherkasova, A P; Selyatitskaya, V G

    2013-01-01

    It was studied the contents of corticosteroid hormones in the adrenal gland, plasma and 11beta-hydroxysteroid dehydrogenase activity (11betaHSD) in the liver and kidneys, as well as the activity of angiotensin-converting enzyme (ACE) in blood plasma, lung, renal cortex and liver of male rats in the dynamics of SiO2-induced inflammation. The study showed that chronic granulomatous inflammation in rats was accompanied by an initial short-term reaction to the activation of synthesis of the main glucocorticoid hormone, followed by specific inhibition of synthesis of this hormone as well as 11betaHSD activity in the adrenal gland. Inflammation caused less pronounced changes in the functional state of the renin-angiotensin system, however, inhibition of ACE activity observed in plasma, liver and kidneys during the initial period of inflammation. Factor analysis revealed a violation of intersystem relations of hypothalamic-pituitary-adrenocortical and renin-angiotensin systems in inflammation due, probably, to the modulating influence of cytokines.

  13. Podocyte-specific overexpression of human angiotensin-converting enzyme 2 attenuates diabetic nephropathy in mice.

    PubMed

    Nadarajah, Renisha; Milagres, Rosangela; Dilauro, Marc; Gutsol, Alex; Xiao, Fengxia; Zimpelmann, Joseph; Kennedy, Chris; Wysocki, Jan; Batlle, Daniel; Burns, Kevin D

    2012-08-01

    Angiotensin-converting enzyme 2 (ACE2) degrades angiotensin II to angiotensin-(1-7) and is expressed in podocytes. Here we overexpressed ACE2 in podocytes in experimental diabetic nephropathy using transgenic methods where a nephrin promoter drove the expression of human ACE2. Glomeruli from these mice had significantly increased mRNA, protein, and activity of ACE2 compared to wild-type mice. Male mice were treated with streptozotocin to induce diabetes. After 16 weeks, there was no significant difference in plasma glucose levels between wild-type and transgenic diabetic mice. Urinary albumin was significantly increased in wild-type diabetic mice at 4 weeks, whereas albuminuria in transgenic diabetic mice did not differ from wild-type nondiabetic mice. However, this effect was transient and by 16 weeks both transgenic and nontransgenic diabetic mice had similar rates of proteinuria. Compared to wild-type diabetic mice, transgenic diabetic mice had an attenuated increase in mesangial area, decreased glomerular area, and a blunted decrease in nephrin expression. Podocyte numbers decreased in wild-type diabetic mice at 16 weeks, but were unaffected in transgenic diabetic mice. At 8 weeks, kidney cortical expression of transforming growth factor-β1 was significantly inhibited in transgenic diabetic mice as compared to wild-type diabetic mice. Thus, the podocyte-specific overexpression of human ACE2 transiently attenuates the development of diabetic nephropathy.

  14. Attenuation of angiotensin converting enzyme inhibitor induced cough by iron supplementation: role of nitric oxide.

    PubMed

    Bhalla, Payal; Singh, Narinder Pal; Ravi, Krishnan

    2011-12-01

    The present study examined whether (1) the cough associated with angiotensin converting enzyme inhibitor therapy is attenuated by oral intake of iron and anti-oxidants, and (2) nitric oxide (NO) has any role in this attenuation. Of the 100 patients under investigation, cough occurred in 28 of them with preponderance in females. All the 28 patients were followed up for six weeks: the first two weeks were the observation period and the remaining four weeks the experimentation period. After the observation period, 11 patients received a single oral dose of ferrous sulphate (200 mg), eight received vitamin E (200 mg, o.d.) and vitamin C (150 mg, o.d.) and nine were given placebo during the experimentation period. Cough scoring, serum NO and malondialdehyde (MDA) levels were determined during both the periods. While there were significant decreases in cough scores, NO and MDA levels between these two periods in the iron group, cough scores and MDA level decreased significantly in the anti-oxidant group. None of these parameters changed in the control group. NO level was found to be increased significantly in patients who developed cough (n = 28) compared with those who did not cough (n = 72). These results suggest that iron supplementation suppresses cough in patients on ACE-I therapy through its effect on NO generation.

  15. Effect of phlorotannins isolated from Ecklonia cava on angiotensin I-converting enzyme (ACE) inhibitory activity

    PubMed Central

    Wijesinghe, W.A.J.P.; Ko, Seok-Chun

    2011-01-01

    Inhibition of angiotensin I-converting enzyme (ACE) activity is the most common mechanism underlying the lowering of blood pressure. In the present study, five organic extracts of a marine brown seaweed Ecklonia cava were prepared by using ethanol, ethyl acetate, chloroform, hexane, and diethyl ether as solvents, which were then tested for their potential ACE inhibitory activities. Ethanol extract showed the strongest ACE inhibitory activity with an IC50 value of 0.96 mg/ml. Five kinds of phlorotannins, phloroglucinol, triphlorethol-A, eckol, dieckol, and eckstolonol, were isolated from ethanol extract of E. cava, which exhibited potential ACE inhibition. Dieckol was the most potent ACE inhibitor and was found to be a non-competitive inhibitor against ACE according to Lineweaver-Burk plots. Dieckol had an inducible effect on the production of NO in EAhy926 cells without having cytotoxic effect. The results of this study indicate that E. cava could be a potential source of phlorotannins with ACE inhibitory activity for utilization in production of functional foods. PMID:21556221

  16. Serum Levels of Copper, Ceruloplasmin and Angiotensin Converting Enzyme among Silicotic and Non-Silicotic Workers

    PubMed Central

    Beshir, Safia; Aziz, Hisham; Shaheen, Weam; Eltahlawy, Eman

    2015-01-01

    BACKGROUND: Silicosis is the most frequently occurring pneumoconiosis. AIM: Measurement of serum levels of Angiotensin converting enzyme (ACE), Copper (Cu) and Ceruloplasmin (Cp) in cement workers occupationally exposed to silica dust as biomarkers of exposure rather than biomarkers of effect for silicosis. METHODS: Plain chest X-ray & pulmonary functions were done for 30 silicotic and 42 non-silicotic workers and 42 controls. CT scan was done for the exposed groups. Serum levels of Cu, Cp and ACE were estimated. RESULTS: The results showed a higher significant difference between the exposed groups and controls, and between the two exposed groups regarding the mean levels of all measured biochemical parameters. The pulmonary functions were significantly lower among silicotic workers than controls and non-silicotic groups. There was a significant positive correlation between duration of employment and serum ACE and Cu. CONCLUSION: Since respirable dust exposure-linked lung fibrosis disease is non-curable, the biochemical parameters (Cu, ACE and Cp) can be used as exposure biomarkers to silica dust, providing a better way for early diagnosis of this deadly disease. Down regulating the inflammatory responses could potentially reduce the adverse clinical pulmonary effects of air pollution. PMID:27275272

  17. Effect of phlorotannins isolated from Ecklonia cava on angiotensin I-converting enzyme (ACE) inhibitory activity.

    PubMed

    Wijesinghe, W A J P; Ko, Seok-Chun; Jeon, You-Jin

    2011-04-01

    Inhibition of angiotensin I-converting enzyme (ACE) activity is the most common mechanism underlying the lowering of blood pressure. In the present study, five organic extracts of a marine brown seaweed Ecklonia cava were prepared by using ethanol, ethyl acetate, chloroform, hexane, and diethyl ether as solvents, which were then tested for their potential ACE inhibitory activities. Ethanol extract showed the strongest ACE inhibitory activity with an IC(50) value of 0.96 mg/ml. Five kinds of phlorotannins, phloroglucinol, triphlorethol-A, eckol, dieckol, and eckstolonol, were isolated from ethanol extract of E. cava, which exhibited potential ACE inhibition. Dieckol was the most potent ACE inhibitor and was found to be a non-competitive inhibitor against ACE according to Lineweaver-Burk plots. Dieckol had an inducible effect on the production of NO in EAhy926 cells without having cytotoxic effect. The results of this study indicate that E. cava could be a potential source of phlorotannins with ACE inhibitory activity for utilization in production of functional foods.

  18. Endothelin-converting enzyme is a plausible target gene for hypoxia-inducible factor.

    PubMed

    Khamaisi, Mogher; Toukan, Hala; Axelrod, Jonathan H; Rosenberger, Christian; Skarzinski, Galia; Shina, Ahuva; Meidan, Rina; Koesters, Robert; Rosen, Seymour; Walkinshaw, Gail; Mimura, Imari; Nangaku, Masaomi; Heyman, Samuel N

    2015-04-01

    Renal endothelin-converting enzyme (ECE)-1 is induced in experimental diabetes and following radiocontrast administration, conditions characterized by renal hypoxia, hypoxia-inducible factor (HIF) stabilization, and enhanced endothelin synthesis. Here we tested whether ECE-1 might be a HIF-target gene in vitro and in vivo. ECE-1 transcription and expression increased in cultured vascular endothelial and proximal tubular cell lines, subject to hypoxia, to mimosine or cobalt chloride. These interventions are known to stabilize HIF signaling by inhibition of HIF-prolyl hydroxylases. In rats, HIF-prolyl-hydroxylase inhibition by mimosine or FG-4497 increased HIF-1α immunostaining in renal tubules, principally in distal nephron segments. This was associated with markedly enhanced ECE-1 protein expression, predominantly in the renal medulla. A progressive and dramatic increase in ECE-1 immunostaining over time, in parallel with enhanced HIF expression, was also noted in conditional von Hippel-Lindau knockout mice. Since HIF and STAT3 are cross-stimulated, we triggered HIF expression by STAT3 activation in mice, transfected by or injected with a chimeric IL-6/IL-6-receptor protein, and found a similar pattern of enhanced ECE-1 expression. Chromatin immunoprecipitation sequence (ChIP-seq) and PCR analysis in hypoxic endothelial cells identified HIF binding at the ECE-1 promoter and intron regions. Thus, our findings suggest that ECE-1 may be a novel HIF-target gene.

  19. Preconception and pregnancy management of women with diabetic nephropathy on angiotensin converting enzyme inhibitors.

    PubMed

    Podymow, Tiina; Joseph, Geena

    2015-02-01

    Angiotensin converting enzyme (ACE) inhibitors are the mainstay of treatment for diabetic nephropathy to slow progression of disease. Diabetic women of childbearing age with nephropathy should be treated with ACE inhibitors as per guidelines in the pre-pregnancy period. ACE inhibitor use and exposure in the first trimester is controversial and requires counselling pre-pregnancy regarding the risks and benefits of use up to the first trimester, as well as the need to stop ACE inhibitors prior to the second trimester. Current evidence does not suggest that ACE inhibitors in the first trimester are associated with a greater risk of fetal malformations when compared to other antihypertensives. This topic is reviewed in depth, along with blood pressure targets in pregnant women with diabetic proteinuric disease, evidence for prevention of pre-eclampsia, self-monitoring of blood pressures at home in the latter half of pregnancy and the signs and symptoms of pre-eclampsia, proteinuria evolution in pregnancy, renal function prognosis, and restarting ACE inhibitors when breast feeding in the post-partum period.

  20. Endotoxin reduces specific pulmonary uptake of radiolabeled monoclonal antibody to angiotensin-converting enzyme

    SciTech Connect

    Muzykantov, V.R.; Puchnina, E.A.; Atochina, E.N.; Hiemish, H.; Slinkin, M.A.; Meertsuk, F.E.; Danilov, S.M. )

    1991-03-01

    The biodistribution of radiolabeled monoclonal antibody (Mab) to angiotensin-converting enzyme (ACE) was examined in normal and endotoxin-treated rats. Endotoxin administration at a dose of 4 mg/kg induced mild or middle pulmonary edema. The ACE activity in lung homogenate remained virtually unchanged, while the activity of serum ACE increased 15 hr after endotoxin infusion. In normal rats, anti-ACE Mab accumulates specifically in the lung after i.v. injection. Endotoxin injection induces reduction of specific pulmonary uptake of this antibody. Even in non-edematous endotoxemia, the accumulation of anti-ACE Mab antibody (Mab 9B9) decreased from 19.02 to 11.91% of ID/g of tissue without any change in accumulation of control nonspecific IgG. The antibody distribution in other organs and its blood level were almost the same as in the control. In a case of endotoxemia accompanied by increased microvascular permeability, the lung accumulation of Mab 9B9 was reduced to 9.17% of ID/g of tissue, while the accumulation of nonspecific IgG increased to 1.44% versus 0.89% in the control.

  1. [Psychotropic effects of angiotensin-converting enzyme inhibitors: what are the arguments?].

    PubMed

    Mesure, G; Fallet, A; Chevalier, J F

    1995-01-01

    The authors report a case of acute mania induced by perindopril (Coversyl) in a 57 year old man with no prior history of mental illness. This Angiotensin-Converting Enzyme Inhibitor (ACEI) had been introduced eight days prior to the first signs of excitation, in order to treat recently diagnosed arterial hypertension. Without proof of reintroduction, and on the basis of clinical observations, the attribution appears plausible. Similar observations have been made for other molecules in this class of medication, such as captopril (Lopril). A review of literature regroups recent data concerning psychotropic effects of ACEIs. Several reports claim that captopril clearly acts as an antidepressant. Studies on the mood or the quality of life of treated hypertensive patients show ACEIs to have an euphoric-type positive effect compared to other anti-hypertensive treatments. Captopril and perindopril also act like potential antidepressants in experimental models of antidepression. Furthermore, pharmacologic data confirm that the most lipophilic ACEIs penetrate the central nervous system and argue in favor of the role of these molecules in activating central opioides. As these data provide evidence of mood swing in some patients, but also of an overall benefit in hypertensive populations, the clinical importance of the antidepressant effect of ACEIs needs further investigations.

  2. Structural characterization of angiotensin I-converting enzyme in complex with a selenium analogue of captopril.

    PubMed

    Akif, Mohd; Masuyer, Geoffrey; Schwager, Sylva L U; Bhuyan, Bhaskar J; Mugesh, Govindasamy; Isaac, R Elwyn; Sturrock, Edward D; Acharya, K Ravi

    2011-10-01

    Human somatic angiotensin I-converting enzyme (ACE), a zinc-dependent dipeptidyl carboxypeptidase, is central to the regulation of the renin-angiotensin aldosterone system. It is a well-known target for combating hypertension and related cardiovascular diseases. In a recent study by Bhuyan and Mugesh [Org. Biomol. Chem. (2011) 9, 1356-1365], it was shown that the selenium analogues of captopril (a well-known clinical inhibitor of ACE) not only inhibit ACE, but also protect against peroxynitrite-mediated nitration of peptides and proteins. Here, we report the crystal structures of human testis ACE (tACE) and a homologue of ACE, known as AnCE, from Drosophila melanogaster in complex with the most promising selenium analogue of captopril (SeCap) determined at 2.4 and 2.35 Å resolution, respectively. The inhibitor binds at the active site of tACE and AnCE in an analogous fashion to that observed for captopril and provide the first examples of a protein-selenolate interaction. These new structures of tACE-SeCap and AnCE-SeCap inhibitor complexes presented here provide important information for further exploration of zinc coordinating selenium-based ACE inhibitor pharmacophores with significant antioxidant activity.

  3. Age and the pharmacokinetics of angiotensin converting enzyme inhibitors enalapril and enalaprilat.

    PubMed Central

    Hockings, N; Ajayi, A A; Reid, J L

    1986-01-01

    The pharmacokinetics of angiotension converting enzyme (ACE) inhibitors enalapril (10 mg orally) and its active metabolite, enalaprilat (10 mg intravenously) were studied in nine young healthy volunteers aged 22-30 years and nine sex matched elderly subjects aged 65-73 years. After both drugs, a biexponential curve was fitted to the decline in plasma enalaprilat concentration. Area under the plasma concentration-time curve (AUC) was greater in the elderly for both drugs. Clearance (CL) and clearance/bioavailability (CL/F) were less in the elderly for enalaprilat and enalapril, respectively. There was no difference in F between young (0.62 +/- 0.16) and elderly subjects (0.61 +/- 0.15). Enalaprilat CL and enalapril CL/F were significantly and positively correlated to endogenous creatinine clearance. There was a significant difference in the weight corrected volume of distribution at steady state after enalaprilat between the young and elderly (P less than 0.02). The relationship between plasma enalaprilat concentrations and percentage ACE inhibition, using the Hill equation, showed no difference in the sensitivity to ACE inhibition between the young and the elderly group. The pharmacokinetic differences observed are likely to be related to an age dependent decline in renal function as well as changes in body composition. Kinetic differences partly explain the greater pharmacodynamic response in the elderly. PMID:3011046

  4. Cardiac expression patterns of endothelin-converting enzyme (ECE): implications for conduction system development.

    PubMed

    Sedmera, David; Harris, Brett S; Grant, Elizabeth; Zhang, Ning; Jourdan, Jane; Kurkova, Dana; Gourdie, Robert G

    2008-06-01

    The spatiotemporal distribution of the endothelin-converting enzyme (ECE) protein in the embryonic chick heart and the association of this polypeptide with the developing cardiac conduction system is described here for the first time. Further, we show how cardiac hemodynamic load directly affects ECE level and distribution. Endothelin (ET) is a cytokine involved in the inductive recruitment of Purkinje fibers. ET is produced by proteolytic cleavage of Big-ET by ECE. We generated an antibody against chick ECE recognizing a single band at approximately 70 kD to correlate the cardiac expression of this protein with that reported previously for its mRNA. ECE protein expression was more widespread compared to its mRNA, being present in endothelial cells, mesenchymal cells, and myocytes, and particularly enriched in the trabeculae and nascent ventricular conduction system. The myocardial expression was significantly modified under experimentally altered hemodynamic loading. In vivo, ET receptor blockade with bosentan delayed activation sequence maturation. These data support a role for ECE in avian cardiac conduction system differentiation and maturation.

  5. Calcium antagonists and converting enzyme inhibitors reduce renal injury by different mechanisms.

    PubMed

    Dworkin, L D; Benstein, J A; Parker, M; Tolbert, E; Feiner, H D

    1993-04-01

    Both glomerular hypertension and hypertrophy have been associated with the development of glomerular injury in models of hypertension and reduced renal mass. The purpose of this study was to examine the effects of antihypertensive therapy on these parameters in the remnant kidney model of progressive glomerular sclerosis. Rats underwent 5/6 nephrectomy and were randomly assigned to receive either no therapy, the calcium entry blocker (CEB), nifedipine, or the angiotensin converting enzyme inhibitor (CEI), enalapril. Administration of either drug was associated with a reduction in systemic blood pressure and in the severity of glomerular injury assessed eight weeks after renal ablation. Micropuncture studies four weeks after ablation revealed that systemic and glomerular capillary pressure were high in untreated remnant kidney rats and reduced by enalapril. Administration of nifedipine was associated with a decline in systemic pressure, however, plasma renin levels increased, causing efferent arteriolar vasoconstriction and persistence of glomerular hypertension. Morphometric analysis showed that kidney weight, glomerular volume and glomerular capillary radius were lower in nifedipine treated rats than in the other two groups, indicating that the CEB, but not enalapril, inhibited the hypertrophic response to ablation of renal mass. Therefore, both CEIs and CEBs reduce glomerular injury in rats with remnant kidneys but they may act by different mechanisms. CEI reduce glomerular capillary pressure while CEBs inhibit compensatory kidney growth.

  6. Increased risk of pneumonia associated with angiotensin-converting enzyme (CD143) rs4340 polymorphism.

    PubMed

    Zhang, Xiaofang; Liu, Fangzhu

    2016-08-01

    The study aims to investigate the genetic association between rs4340 polymorphism at intron 16 of the angiotensin-converting enzyme (CD143) gene and pneumonia predisposition. Electronic database of PubMed, Embase, and CNKI (China National Knowledge Infrastructure) was searched for the studies addressing the association between CD143 rs4340 genotypes and pneumonia risk. The odds ratio (OR) with its 95 % confidence interval (CI) was employed to estimate the association. In total, ten case-control studies, including 1239 pneumonia cases and 2400 healthy controls, met the inclusion criteria. Our results showed a significant association between rs4340 SNP and pneumonia risk using the recessive model (OR 1.43, 95 % CI 1.20-1.70). A significantly increased risk was also indicated under the recessive model in Asian populations (OR 1.63, 95 % CI 1.16-2.30), Caucasian populations (OR 1.34, 95 % CI 1.09-1.65), community-acquired pneumonia (OR 1.42, 95 % CI 1.16-1.75) rather than nosocomial pneumonia (OR 1.47, 95 % CI 0.97-2.23). However, further studies with gene-gene and gene-environmental interactions should be considered to confirm this association.

  7. Effects of Angiotensin Converting Enzyme Inhibitors on Liver Fibrosis in HIV and Hepatitis C Coinfection.

    PubMed

    Reese, Lindsey J; Tider, Diane S; Stivala, Alicia C; Fishbein, Dawn A

    2012-01-01

    Background. Liver fibrosis is accelerated in HIV and hepatitis C coinfection, mediated by profibrotic effects of angiotensin. The objective of this study was to determine if angiotensin converting enzyme inhibitors (ACE-Is) attenuate liver fibrosis in coinfection. Methods. A retrospective review of 156 coinfected subjects was conducted to analyze the association between exposure to ACE-Is and liver fibrosis. Noninvasive indices of liver fibrosis (APRI, FIB-4, Forns indices) were compared between subjects who had taken ACE-Is and controls who had not taken them. Linear regression was used to evaluate ACE-I use as an independent predictor of fibrosis. Results. Subjects taking ACE-Is for three years were no different than controls on the APRI and the FIB-4 but had significantly higher scores than controls on the Forns index, indicating more advanced fibrosis. The use of ACE-Is for three years remained independently associated with an elevated Forns score when adjusted for age, race, and HIV viral load (P < 0.001). There were significant associations between all of the indices and significant fibrosis, as determined clinically and radiologically. Conclusions. There was not a protective association between angiotensin inhibition and liver fibrosis in coinfection. These noninvasive indices may be useful for ruling out significant fibrosis in coinfection.

  8. Diagnostic use of angiotensin converting enzyme inhibitors in radioisotope evaluation of unilateral renal artery stenosis

    SciTech Connect

    Kremer Hovinga, T.K.; de Jong, P.E.; Piers, D.A.; Beekhuis, H.; van der Hem, G.K.; de Zeeuw, D.

    1989-05-01

    Iodine-123 hippurate renography, (/sup 99m/Tc)diethylenetriaminepentaacetic acid (DTPA) renography, and (/sup 99m/Tc)dimercapto succinic acid (DMSA) renal scintigraphy were performed before and during angiotensin converting enzyme (ACE) inhibition in a group of 15 hypertensive patients with angiographically ''significant'' unilateral renal artery stenosis. Visual and quantitative evaluation of the three radioisotope methods before ACE inhibition already disclosed abnormalities suggestive of renal artery stenosis in a high percentage (87%, 60%, and 60%, respectively) in this group of patients, but ACE inhibition further improved the diagnostic yield in all three methods (93%, 86%, and 80%). Iodine-123 hippurate renography was at least as useful as (/sup 99m/Tc)DTPA renography in this respect, while (/sup 99m/Tc)DMSA scintigraphy can be used particularly in segmental stenosis. Despite a large drop in blood pressure after ACE inhibition little adverse reactions were seen and overall renal function was fairly well maintained, the exceptions noted in patients with initially a more impaired renal function.

  9. Angiotensin I-Converting Enzyme Inhibitor Derived from Cross-Linked Oyster Protein

    PubMed Central

    Xie, Cheng-Liang; Kim, Jin-Soo; Ha, Jong-Myung; Choung, Se-Young

    2014-01-01

    Following cross-linking by microbial transglutaminase, modified oyster proteins were hydrolyzed to improve inhibitory activity against angiotensin-converting enzyme (ACE) inhibitory activity with the use of a single protease, or a combination of six proteases. The oyster hydrolysate with the lowest 50% ACE inhibitory concentration (IC50) of 0.40 mg/mL was obtained by two-step hydrolysis of the cross-linked oyster protein using Protamex and Neutrase. Five ACE inhibitory peptides were purified from the oyster hydrolysate using a multistep chromatographic procedure comprised of ion-exchange, size exclusion, and reversed-phase liquid chromatography. Their sequences were identified as TAY, VK, KY, FYN, and YA, using automated Edman degradation and mass spectrometry. These peptides were synthesized, and their IC50 values were measured to be 16.7, 29.0, 51.5, 68.2, and 93.9 μM, respectively. Toxicity of the peptides on the HepG2 cell line was not detected. The oyster hydrolysate also significantly decreased the systolic blood pressure of spontaneously hypertensive rats (SHR). The antihypertensive effect of the oyster hydrolysate on SHR was rapid and long-lasting, compared to commercially obtained sardine hydrolysate. These results suggest that the oyster hydrolysate could be a source of effective nutraceuticals against hypertension. PMID:25140307

  10. Nitrile-converting enzymes as a tool to improve biocatalysis in organic synthesis: recent insights and promises.

    PubMed

    Gong, Jin-Song; Shi, Jin-Song; Lu, Zhen-Ming; Li, Heng; Zhou, Zhe-Min; Xu, Zheng-Hong

    2017-02-01

    Nitrile-converting enzymes, including nitrilase and nitrile hydratase (NHase), have received increasing attention from researchers of industrial biocatalysis because of their critical role as a tool in organic synthesis of carboxylic acids and amides from nitriles. To date, these bioconversion approaches are considered as one of the most potential industrial processes using resting cells or purified enzymes as catalysts for production of food additives, pharmaceutical, and agrochemical precursors. This review focuses on the distribution and catalytic mechanism research of nitrile-converting enzymes in recent years. Molecular biology aspects to improve the biocatalytic performance of microbial nitrilase and NHase are demonstrated. The process developments of microbial nitrilase and NHase for organic synthesis are also discussed.

  11. A novel lactone-forming carboxylesterase: molecular identification of a tuliposide A-converting enzyme in tulip.

    PubMed

    Nomura, Taiji; Ogita, Shinjiro; Kato, Yasuo

    2012-06-01

    Tuliposides, the glucose esters of 4-hydroxy-2-methylenebutanoate and 3,4-dihydroxy-2-methylenebutanoate, are major secondary metabolites in tulip (Tulipa gesneriana). Their lactonized aglycons, tulipalins, function as defensive chemicals due to their biological activities. We recently found that tuliposide-converting enzyme (TCE) purified from tulip bulbs catalyzed the conversion of tuliposides to tulipalins, but the possibility of the presence of several TCE isozymes was raised: TCE in tissues other than bulbs is different from bulb TCE. Here, to prove this hypothesis, TCE was purified from petals, which have the second highest TCE activity after bulbs. The purified enzyme, like the bulb enzyme, preferentially accepted tuliposides as substrates, with 6-tuliposide A the best substrate, which allowed naming the enzyme tuliposide A-converting enzyme (TCEA), but specific activity and molecular mass differed between the petal and bulb enzymes. After peptide sequencing, a novel cDNA (TgTCEA) encoding petal TCEA was isolated, and the functional characterization of the recombinant enzyme verified that TgTCEA catalyzes the conversion of 6-tuliposide A to tulipalin A. TgTCEA was transcribed in all tulip tissues but not in bulbs, indicating the presence of a bulb-specific TgTCEA, as suggested by the distinct enzymatic characters between the petal and bulb enzymes. Plastidial localization of TgTCEA enzyme was revealed, which allowed proposing a cytological mechanism of TgTCE-mediated tulipalin formation in the tulip defensive strategy. Site-directed mutagenesis of TgTCEA suggested that the oxyanion hole and catalytic triad characteristic of typical carboxylesterases are essential for the catalytic process of TgTCEA enzyme. To our knowledge, TgTCEA is the first identified member of the lactone-forming carboxylesterases, specifically catalyzing intramolecular transesterification.

  12. A Novel Lactone-Forming Carboxylesterase: Molecular Identification of a Tuliposide A-Converting Enzyme in Tulip1[W

    PubMed Central

    Nomura, Taiji; Ogita, Shinjiro; Kato, Yasuo

    2012-01-01

    Tuliposides, the glucose esters of 4-hydroxy-2-methylenebutanoate and 3,4-dihydroxy-2-methylenebutanoate, are major secondary metabolites in tulip (Tulipa gesneriana). Their lactonized aglycons, tulipalins, function as defensive chemicals due to their biological activities. We recently found that tuliposide-converting enzyme (TCE) purified from tulip bulbs catalyzed the conversion of tuliposides to tulipalins, but the possibility of the presence of several TCE isozymes was raised: TCE in tissues other than bulbs is different from bulb TCE. Here, to prove this hypothesis, TCE was purified from petals, which have the second highest TCE activity after bulbs. The purified enzyme, like the bulb enzyme, preferentially accepted tuliposides as substrates, with 6-tuliposide A the best substrate, which allowed naming the enzyme tuliposide A-converting enzyme (TCEA), but specific activity and molecular mass differed between the petal and bulb enzymes. After peptide sequencing, a novel cDNA (TgTCEA) encoding petal TCEA was isolated, and the functional characterization of the recombinant enzyme verified that TgTCEA catalyzes the conversion of 6-tuliposide A to tulipalin A. TgTCEA was transcribed in all tulip tissues but not in bulbs, indicating the presence of a bulb-specific TgTCEA, as suggested by the distinct enzymatic characters between the petal and bulb enzymes. Plastidial localization of TgTCEA enzyme was revealed, which allowed proposing a cytological mechanism of TgTCE-mediated tulipalin formation in the tulip defensive strategy. Site-directed mutagenesis of TgTCEA suggested that the oxyanion hole and catalytic triad characteristic of typical carboxylesterases are essential for the catalytic process of TgTCEA enzyme. To our knowledge, TgTCEA is the first identified member of the lactone-forming carboxylesterases, specifically catalyzing intramolecular transesterification. PMID:22474185

  13. A review of the preclinical cardiovascular pharmacology of cilazapril, a new angiotensin converting enzyme inhibitor

    PubMed Central

    Waterfall, J. F.

    1989-01-01

    1 Cilazapril is the monoethyl ester prodrug form of the di-acid cilazaprilat, a new angiotensin converting enzyme (ACE) inhibitor. Cilazaprilat has an IC50 of 1.9 nM as an inhibitor of rabbit lung ACE in vitro making it one of the most potent ACE inhibitors currently available. Studies on a wide range of other enzymes show that the inhibition is highly specific. 2 An oral dose of 0.1 mg kg-1 cilazapril evoked the same maximum degree of plasma ACE inhibition (∼76%) in the rat as 0.25 mg kg-1 enalapril. Cilazapril (0.25 mg kg-1 p.o.) inhibited plasma ACE by > 95%. The rate of recovery of ACE activity was slower with cilazapril (5-6% h-1) than with enalapril (10% h-1). 3 In anaesthetised rats cilazaprilat was equipotent with ramiprilat and slightly more potent (1.5×) than enalaprilat as an inhibitor of the angiotensin I pressor response. 4 Following oral administration to conscious rats and intravenous administration to anaesthetised dogs, cilazapril was 2-4.5× more potent than enalapril as an ACE inhibitor. 5 In cats cilazapril (0.1 and 0.3 mg kg-1 p.o.) dose dependently decreased plasma ACE activity and the angiotensin pressor response. Peak effects occurred at 2 h after dosing and plasma ACE inhibition was maintained at ≥ 50% for up to 18 h. Mean arterial pressure was also decreased dose dependently with a peak effect at 3-4 h. 6 Daily oral dosing of cilazapril (30 mg kg-1 p.o.) to spontaneously hypertensive rats evoked a progressive and prolonged (24 h) antihypertensive response with a maximum decrease in systolic blood pressure of 110 mm Hg. 7 Cilazapril (10 mg kg-1 p.o. twice daily for 3.5 days) progressively decreased blood pressure in volume depleted renal hypertensive dogs. The maximum fall in systolic pressure was 39 ± 6 mm Hg. 8 Haemodynamic studies in open chest anaesthetised dogs showed that the hypotensive response to intravenous cilazapril was accompanied by a reduction in total peripheral resistance. Small decreases in cardiac output and

  14. Insertion/Deletion Polymorphisms and Serum Angiotensin-converting Enzyme Levels in Iranian Patients with Sarcoidosis

    PubMed Central

    JAVADI, Alireza; SHAMAEI, Masoud; ZAREI, Masoud; REZAEIAN, Lida; KIANI, Arda; ABEDINI, Atefeh

    2016-01-01

    Background: Sarcoidosis is a multisystem inflammatory disease of unknown origin with characterization of small granulomas. Angiotensin-converting enzyme (ACE) is a pathophysiologic marker of sarcoidosis. We present the ACE insertion/deletion (I/D) polymorphism in correlation with serum ACE level in Iranian patients with sarcoidosis. Methods: From Jan 2014 to Jan 2015, 102 Iranian patients who histopathologically diagnosed for sarcoidosis and 192 healthy age and sex-matched controls were recruited. PCR was used for detection of I/D polymorphism in ACE gene. Results: Frequency of II/ID/DD genotype in sarcoidosis disease was 17%, 35.5%, and 47.1%, respectively. The frequency of D allele was 0.65. A significant association between I/D genotypes and mean of sACE level was seen (DD=85.2±22.9, P<0.001). More frequent genotype in sarcoidosis patients was DD (47%), ID genotype (45.9%) was found more in controls. Logistic regression analysis adjusting age and sex showed that ID to II (OR=0.35, 95%CI=0.17–0.73, P=0.005) and DD to II (OR=2.11, 95%CI=0.98–4.54, P=0.05) could be considered as a predictor factor for the disease activity. No significant model for men in sarcoidosis group was seen, while women with II/ID were associated with a reduced risk for the disease. Conclusion: Although more regional studies with appropriate statistical scale must be done to provide a better diagnosis and prognostic tool for this disease, this study demonstrates that ID and DD genotype could be predictive factors for sarcoidosis. PMID:28032065

  15. Angiotensin-Receptor Blocker, Angiotensin-Converting Enzyme Inhibitor, and Risks of Atrial Fibrillation

    PubMed Central

    Hsieh, Yu-Cheng; Hung, Chen-Ying; Li, Cheng-Hung; Liao, Ying-Chieh; Huang, Jin-Long; Lin, Ching-Heng; Wu, Tsu-Juey

    2016-01-01

    Abstract Both angiotensin-receptor blockers (ARB) and angiotensin-converting enzyme inhibitors (ACEI) have protective effects against atrial fibrillation (AF). The differences between ARB and ACEI in their effects on the primary prevention of AF remain unclear. This study compared ARB and ACEI in combined antihypertensive medications for reducing the risk of AF in patients with hypertension, and determined which was better for AF prevention in a nationwide cohort study. Patients aged ≥55 years and with a history of hypertension were identified from Taiwan National Health Insurance Research Database. Medical records of 25,075 patients were obtained, and included 6205 who used ARB, 8034 who used ACEI, and 10,836 nonusers (no ARB or ACEI) in their antihypertensive regimen. Cox regression models were applied to estimate the hazard ratio (HR) for new-onset AF. During an average of 7.7 years’ follow-up, 1619 patients developed new-onset AF. Both ARB (adjusted HR: 0.51, 95% CI 0.44–0.58, P < 0.001) and ACEI (adjusted HR: 0.53, 95% CI 0.47–0.59, P < 0.001) reduced the risk of AF compared to nonusers. Subgroup analysis showed that ARB and ACEI were equally effective in preventing new-onset AF regardless of age, gender, the presence of heart failure, diabetes, and vascular disease, except for those with prior stroke or transient ischemic attack (TIA). ARB prevents new-onset AF better than ACEI in patients with a history of stroke or TIA (log-rank P = 0.012). Both ARB and ACEI reduce new-onset AF in patients with hypertension. ARB prevents AF better than ACEI in patients with a history of prior stroke or TIA. PMID:27196491

  16. The angiotensin-converting enzyme (ACE) gene family of Bombyx mori.

    PubMed

    Yan, Hai-Yan; Mita, Kazuei; Zhao, Xia; Tanaka, Yoshikazu; Moriyama, Minoru; Wang, Huabin; Iwanaga, Masashi; Kawasaki, Hideki

    2017-04-15

    We previously reported regarding an ecdysone-inducible angiotensin-converting enzyme (ACE) gene. We found another four ACE genes in the Bombyx genome. The present study was undertaken to clarify the evolutionally changed function of the ACE of Bombyx mori. Core regions of deduced amino acid sequences of ACE genes were compared with those of other insect ACE genes. Five Bombyx genes have the conserved Zn(2+)-binding-site motif (HEXXH); however, BmAcer4 has only one and BmAcer3 has no catalytic ligand. BmAcer1 and BmAcer2 were expressed in several organs. BmAcer3 was expressed in testes, and BmAcer4 and BmAcer5 were expressed in compound eyes; however, the transcription levels of these three genes were very low. Quantitative RT-PCR and Western analysis were conducted to determine the tissue distribution and developmental expression of BmAcer1and BmAcer2. Transcripts of BmAcer1 and BmAcer2 were found in the reproductive organs during the larval and pupal stages. BmAcer1 was dominant in fat bodies during the feeding stage and showed high expression in the epidermis, wing discs, and pupal wing tissues after the wandering stage. Its expression patterns in epidermis, wing discs, and wing tissues resembled the hemolymph ecdysteroid titer in the larval and pupal stages. Acer1 was observed in the hemolymph at all stages, appearing to be the source of it are fat bodies, wings, and epidermis, and functioning after being secreted into the hemolymph. BmAcer2 was abundant in the midgut during the feeding stage and after the wandering stage and in silk glands after the pupal stage. We conclude that the evolution of BmAcer occurred through duplication, and, thereafter, functional diversification developed.

  17. Characterization of angiotensin-converting enzyme inhibitory activity of fermented milk produced by Lactobacillus helveticus.

    PubMed

    Chen, Yongfu; Li, Changkun; Xue, Jiangang; Kwok, Lai-yu; Yang, Jie; Zhang, Heping; Menghe, Bilige

    2015-08-01

    Hypertension affects up to 30% of the adult population in most countries. It is a known risk factor for cardiovascular diseases, including coronary heart disease, peripheral artery disease, and stroke. Owing to the increased health awareness of consumers, the application of angiotensin-converting enzyme (ACE)-inhibitory peptides produced by Lactobacillushelveticus to prevent or control high blood pressure has drawn wide attention. A total of 59 L. helveticus strains were isolated from traditional fermented dairy products and the ACE-inhibitory activity of the fermented milks produced with the isolated microorganisms was assayed. The ACE-inhibitory activity of 38 L. helveticus strains was more than 50%, and 3 strains (IMAU80872, IMAU80852, and IMAU80851) expressing the highest ACE-inhibitory activity were selected for further studies. Particularly, the gastrointestinal protease tolerance and thermostability of the ACE-inhibitory activity in the fermented milks were assessed. Based on these 2 criteria, IMAU80872 was found to be superior over the other 2 strains. Furthermore, IMAU80872 exhibited a high in vitro ACE-inhibitory activity at the following fermentation conditions: fermentation temperature at 40°C, inoculation concentration of 1×10(6) cfu/mL, and fermentation for 18h. Finally, by using ultra-performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry analysis, we observed changes of the metabolome along the milk fermentation process of IMAU80872. Furthermore, 6 peptides were identified, which might have ACE-inhibitory activity. In conclusion, we identified a novel ACE-inhibitory L. helveticus strain suitable for the production of fermented milk or other functional dairy products.

  18. Molecular and Thermodynamic Mechanisms of the Chloride-dependent Human Angiotensin-I-converting Enzyme (ACE)*

    PubMed Central

    Yates, Christopher J.; Masuyer, Geoffrey; Schwager, Sylva L. U.; Akif, Mohd; Sturrock, Edward D.; Acharya, K. Ravi

    2014-01-01

    Somatic angiotensin-converting enzyme (sACE), a key regulator of blood pressure and electrolyte fluid homeostasis, cleaves the vasoactive angiotensin-I, bradykinin, and a number of other physiologically relevant peptides. sACE consists of two homologous and catalytically active N- and C-domains, which display marked differences in substrate specificities and chloride activation. A series of single substitution mutants were generated and evaluated under varying chloride concentrations using isothermal titration calorimetry. The x-ray crystal structures of the mutants provided details on the chloride-dependent interactions with ACE. Chloride binding in the chloride 1 pocket of C-domain ACE was found to affect positioning of residues from the active site. Analysis of the chloride 2 pocket R522Q and R522K mutations revealed the key interactions with the catalytic site that are stabilized via chloride coordination of Arg522. Substrate interactions in the S2 subsite were shown to affect chloride affinity in the chloride 2 pocket. The Glu403-Lys118 salt bridge in C-domain ACE was shown to stabilize the hinge-bending region and reduce chloride affinity by constraining the chloride 2 pocket. This work demonstrated that substrate composition to the C-terminal side of the scissile bond as well as interactions of larger substrates in the S2 subsite moderate chloride affinity in the chloride 2 pocket of the ACE C-domain, providing a rationale for the substrate-selective nature of chloride dependence in ACE and how this varies between the N- and C-domains. PMID:24297181

  19. Endothelial Nitric Oxide Synthase and Angiotensin Converting Enzyme Gene Polymorphisms in Migraine Patients

    PubMed Central

    SİPAHİ, Tammam; GÜLDİKEN, Babürhan; KABAYEL, Levent; PALABIYIK, Orkide; ÖZKAN, Hülya; KILIÇ, Tülay Okman; SÜT, Necdet; TURGUT, Nilda

    2013-01-01

    Introduction In this study, we investigated the association of migraine with the Variable Number of Tandem Repeats (VNTR), repeated as 27 base pair, gene polymorphism in intron 4 of the endothelial nitric oxide synthase (eNOS) and the insertion/deletion of angiotensin converting enzyme (ACE) gene polymorphisms. Methods One hundred and five migraine and ninety seven healthy female control subjects were enrolled in the study. The patients were subdivided as migraine with aura and without aura, and the frequency and severity of migraine headaches were recorded. The eNOS VNTR (eNOS 4 a/b) and ACE insertion/deletion gene polymorphisms (ACE I/D) were assessed by polymerase chain reactions. Result The allele and genotype frequencies of eNOS 4 a/b gene polymorphism showed no difference between the migraine and control groups. The genotypic distribution of the ACE I/D gene polymorphism in the migraine group significantly differed from that in the control group. The DD and ID genotype increased the risk of migraine as much as 2.571 (95% CI-1.138–5.811) and 4.453 (95% CI-2.006–9.883) compared to the II genotype. The same increased risk sustained for both genotypes in the migraine with aura subgroup, but only the ID genotype remained as the risk factor in the migraine without aura subgroup (OR-3.750, 95% CI-1.493–9.420). No association of gene polymorphisms with migraine frequency and severity was observed. Conclusion Our findings support the relationship between migraine and the ACE I/D gene polymorphism. However, no association was found between migraine and the eNOS 4 a/b gene polymorphism.

  20. Effect of the Angiotensin I Converting Enzyme Inhibitor, MK-421, on Experimentally Induced Drinking

    NASA Technical Reports Server (NTRS)

    Fregley, Melvin J.; Fater, Dennis C.; Greenleaf, John E.

    1982-01-01

    MK-421, the ethyl ester maleate salt of N-(S)-1-(ethoxycarbonyl)-3-phenyl-propyl- Ala-L-Pro, is an angiotensin I converting enzyme inhibitor. An initial objective was to determine whether MK-421, administered at 0, 2.5, 5.0, 10.0, 20.0 and 40.0 mg/kg, ip to 96 female rats 15 min prior to administration of the beta-adrenergic agonist, isoproterenol (25 microgram/kg, ip), would inhibit the drinking induced by isoproterenol during 2 h after its administration. The water intake induced by isoproterenol was inhibited significantly by 2.5 mg MK-421/kg. When a similar experiment was performed using Angiotensin I (AI) (200 microgram/kg, ip) as the dipsogenic agent, MK-421 (5 mg/kg, ip), administered 15 min prior to AI, inhibited significantly both the dipsogenic and the diuretic effect of AI. However, administration of angiotensin II (AII, 200 microgram/kg, ip) 15 min after MK-421 (5mg/kg) was accompanied by a water intake that did not differ from AII alone. The drink induced by ip administration of 1.0 m NaCl solution (1% of body wt, ip) was not inhibited by administration of MK-421 (5 mg/kg) 15 min prior to allowing access to water while the drink induced by a 24 h dehydration was partially inhibited. Thus, the drinks induced by administraition of either isoproterenol or AI are dependent on formation of AII. That induced by dehydration is partially dependent, while that induced by hypertonic siilinc is independent of the formation of AII.

  1. Angiotensin I-Converting Enzyme Inhibitory Peptides of Chia (Salvia hispanica) Produced by Enzymatic Hydrolysis.

    PubMed

    Segura Campos, Maira Rubi; Peralta González, Fanny; Chel Guerrero, Luis; Betancur Ancona, David

    2013-01-01

    Synthetic angiotensin I-converting enzyme (ACE-I) inhibitors can have undesirable side effects, while natural inhibitors have no side effects and are potential nutraceuticals. A protein-rich fraction from chia (Salvia hispanica L.) seed was hydrolyzed with an Alcalase-Flavourzyme sequential system and the hydrolysate ultrafiltered through four molecular weight cut-off membranes (1 kDa, 3 kDa, 5 kDa, and 10 kDa). ACE-I inhibitory activity was quantified in the hydrolysate and ultrafiltered fractions. The hydrolysate was extensive (DH = 51.64%) and had 58.46% ACE-inhibitory activity. Inhibition ranged from 53.84% to 69.31% in the five ultrafiltered fractions and was highest in the <1 kDa fraction (69.31%). This fraction's amino acid composition was identified and then it was purified by gel filtration chromatography and ACE-I inhibition measured in the purified fractions. Amino acid composition suggested that hydrophobic residues contributed substantially to chia peptide ACE-I inhibitory strength, probably by blocking angiotensin II production. Inhibitory activity ranged from 48.41% to 62.58% in the purified fractions, but fraction F1 (1.5-2.5 kDa) exhibited the highest inhibition (IC50 = 3.97 μg/mL; 427-455 mL elution volume). The results point out the possibility of obtaining bioactive peptides from chia proteins by means of a controlled protein hydrolysis using Alcalase-Flavourzyme sequentional system.

  2. Angiotensin I-Converting Enzyme Inhibitory Peptides of Chia (Salvia hispanica) Produced by Enzymatic Hydrolysis

    PubMed Central

    Segura Campos, Maira Rubi; Peralta González, Fanny; Chel Guerrero, Luis

    2013-01-01

    Synthetic angiotensin I-converting enzyme (ACE-I) inhibitors can have undesirable side effects, while natural inhibitors have no side effects and are potential nutraceuticals. A protein-rich fraction from chia (Salvia hispanica L.) seed was hydrolyzed with an Alcalase-Flavourzyme sequential system and the hydrolysate ultrafiltered through four molecular weight cut-off membranes (1 kDa, 3 kDa, 5 kDa, and 10 kDa). ACE-I inhibitory activity was quantified in the hydrolysate and ultrafiltered fractions. The hydrolysate was extensive (DH = 51.64%) and had 58.46% ACE-inhibitory activity. Inhibition ranged from 53.84% to 69.31% in the five ultrafiltered fractions and was highest in the <1 kDa fraction (69.31%). This fraction's amino acid composition was identified and then it was purified by gel filtration chromatography and ACE-I inhibition measured in the purified fractions. Amino acid composition suggested that hydrophobic residues contributed substantially to chia peptide ACE-I inhibitory strength, probably by blocking angiotensin II production. Inhibitory activity ranged from 48.41% to 62.58% in the purified fractions, but fraction F1 (1.5–2.5 kDa) exhibited the highest inhibition (IC50 = 3.97 μg/mL; 427–455 mL elution volume). The results point out the possibility of obtaining bioactive peptides from chia proteins by means of a controlled protein hydrolysis using Alcalase-Flavourzyme sequentional system. PMID:26904588

  3. Association between Insertion/Deletion Polymorphism in Angiotension Converting Enzyme and Susceptibility to Schizophrenia

    PubMed Central

    MAZAHERI, Hajar; SAADAT, Mostafa

    2015-01-01

    Background: The activity of angiotension converting enzyme (ACE; OMIM: 106180) in different brain regions of patients with schizophrenia changed, suggesting a possible involvement of ACE in psychiatric disorders. Genetic polymorphism of insertion/deletion (I/D; dbSNP rs4646994) in the gene encoding ACE has been well defined. Methods: The present case-control study was performed on 363 (268 males, 95 females) in-patients with schizophrenia diagnosis, and 363 (268 males, 95 females) healthy blood donor controls. The genotypes of I/D ACE polymorphism were determined using PCR method. PCR products were separated and sized by electrophoresis on a 2% agarose gel. The insertion allele (I) was detected as a 478 bp band, and the deletion allele (D) was visualized as a 191 bp band. The association between genotypes of the I/D polymorphism and the schizophrenia risk was examined by use of odds ratios (OR) and 95% of confidence intervals (CIs). Results: Among females, the II genotype significantly decreased the risk of schizophrenia compared with the DD genotype (OR=0.18, 95%CI: 0.04–0.72, P=0.015). There was significant linear trend for the number of the I allele and schizophrenia risk among females (Chi2=5.19, P=0.023). There was no significant association between I/D polymorphism and susceptibility to schizophrenia among male subjects. There was significant interaction between gender and the II genotype (P=0.031). Conclusion: The II genotype of the I/D polymorphism has a protective effect for schizophrenia among females. PMID:25905080

  4. Angiotensin converting enzyme 2 polymorphisms and postexercise hypotension in hypertensive medicated individuals.

    PubMed

    Goessler, Karla F; Polito, Marcos D; Mota, Gloria de F; de Oliveira, Edilamar M; Cornelissen, Véronique A

    2016-12-07

    The renin-angiotensin aldosterone system (RAAS) is associated with diverse physiological responses and adaptations to exercise. The angiotensin converting enzyme (ACE) 2 has vasodilatory effects, which might be associated with the blood pressure (BP) responses to acute exercise. The aim of this study was to investigate the role of ACE2 polymorphisms in postexercise hypotension (PEH). Thirty-four medicated hypertensive (61·3 ± 1·7 years, 76·1 ± 2·7 kg, 160 ± 1·6 cm) men (n = 12) and women (n = 22), participated in a control and a moderate intensity exercise session in a randomized order. After both experimental sessions, they left the laboratory wearing an ambulatory BP device for 24-h monitoring. ACE2 polymorphisms (Int-1 and Int-3) were assessed by polymerase chain reaction. Over the course of 5-h monitoring, we observed a significant reduction in SBP and DBP following exercise in the AA/AG of the Int-1 polymorphism (p-interaction = 0·02 and 0·001, respectively), whereas this could not be found in the individuals homozygous G (p-interaction = 0·76 and 0·51, respectively). With regard to Int-3 polymorphism, individuals AA/AG showed a significant reduction in SBP following exercise (p-interaction <0·0001) but not for DBP (p-interaction = 0·06) whereas GG individuals showed only a significant reduction in DBP following exercise (p-interaction = 0·02). Our results suggest that ACE2 polymorphism could affect PEH; however, larger trials are needed to confirm our findings.

  5. Effect of Jatropha curcas Peptide Fractions on the Angiotensin I-Converting Enzyme Inhibitory Activity

    PubMed Central

    Segura-Campos, Maira R.; Peralta-González, Fanny; Castellanos-Ruelas, Arturo; Chel-Guerrero, Luis A.; Betancur-Ancona, David A.

    2013-01-01

    Hypertension is one of the most common worldwide diseases in humans. Angiotensin I-converting enzyme (ACE) plays an important role in regulating blood pressure and hypertension. An evaluation was done on the effect of Alcalase hydrolysis of defatted Jatropha curcas kernel meal on ACE inhibitory activity in the resulting hydrolysate and its purified fractions. Alcalase exhibited broad specificity and produced a protein hydrolysate with a 21.35% degree of hydrolysis and 34.87% ACE inhibition. Ultrafiltration of the hydrolysate produced peptide fractions with increased biological activity (24.46–61.41%). Hydrophobic residues contributed substantially to the peptides' inhibitory potency. The 5–10 and <1 kDa fractions were selected for further fractionation by gel filtration chromatography. ACE inhibitory activity (%) ranged from 22.66 to 45.96% with the 5–10 kDa ultrafiltered fraction and from 36.91 to 55.83% with the <1 kDa ultrafiltered fraction. The highest ACE inhibitory activity was observed in F2 (IC50 = 6.7 μg/mL) from the 5–10 kDa fraction and F1 (IC50 = 4.78 μg/mL) from the <1 kDa fraction. ACE inhibitory fractions from Jatropha kernel have potential applications in alternative hypertension therapies, adding a new application for the Jatropha plant protein fraction and improving the financial viability and sustainability of a Jatropha-based biodiesel industry. PMID:24224169

  6. Impairing effects of angiotensin-converting enzyme inhibitor Captopril on bone of normal mice.

    PubMed

    Yang, Min; Xia, Chao; Song, Yan; Zhao, Xi; Wong, Man-Sau; Zhang, Yan

    2016-01-15

    There are contradicting results about the effects of angiotensin-converting enzyme inhibitors (ACEIs) on bones. This study was aimed to investigate the effect of ACEI, Captopril, on bone metabolism and histology as well as the action of Captopril on skeletal renin-angiotensin system (RAS) and bradykinin receptor pathway in normal male mice. The urine, serum, tibias and femurs from normal control mice and Captopril-treated (10mg/kg) mice were collected for biochemical, histological and molecular analyses after drug administration for eight weeks. The mice after the treatment with Captopril had a significant decrease of serum testosterone level. The histological measurements showed the loss of trabecular bone mass and trabecular bone number, and the breakage of trabecular bone network as well as the changes of chondrocyte zone at epiphyseal plate in Captopril-treated mice. The defect of Captopril on trabecular bone was reflected by the quantitative bio-parameters from micro-CT. The expression of renin receptor and bradykinin B2 receptor (B2R) was significantly up-regulated in tibia of mice upon to the Captopril treatment, which decreased the ratio of OPG/RANKL and the expression of osteoblastic factor RUNX2. Furthermore, Captopril treatment resulted in the increase of pAkt/Akt and pNFκB expression in tibia. The present study revealed the impairing effects of Captopril on bone via interfering with the circulating sex hormone level and B2R pathway, which suggests that the bone metabolism of patients need to be carefully monitored when being prescribed for ACEIs.

  7. Neural peptidase endothelin-converting enzyme 1 regulates endothelin 1–induced pruritus

    PubMed Central

    Kido-Nakahara, Makiko; Buddenkotte, Jörg; Kempkes, Cordula; Ikoma, Akihiko; Cevikbas, Ferda; Akiyama, Tasuku; Nunes, Frank; Seeliger, Stephan; Hasdemir, Burcu; Mess, Christian; Buhl, Timo; Sulk, Mathias; Müller, Frank-Ulrich; Metze, Dieter; Bunnett, Nigel W.; Bhargava, Aditi; Carstens, Earl; Furue, Masutaka; Steinhoff, Martin

    2014-01-01

    In humans, pruritus (itch) is a common but poorly understood symptom in numerous skin and systemic diseases. Endothelin 1 (ET-1) evokes histamine-independent pruritus in mammals through activation of its cognate G protein–coupled receptor endothelin A receptor (ETAR). Here, we have identified neural endothelin–converting enzyme 1 (ECE-1) as a key regulator of ET-1–induced pruritus and neural signaling of itch. We show here that ETAR, ET-1, and ECE-1 are expressed and colocalize in murine dorsal root ganglia (DRG) neurons and human skin nerves. In murine DRG neurons, ET-1 induced internalization of ETAR within ECE-1–containing endosomes. ECE-1 inhibition slowed ETAR recycling yet prolonged ET-1–induced activation of ERK1/2, but not p38. In a murine itch model, ET-1–induced scratching behavior was substantially augmented by pharmacological ECE-1 inhibition and abrogated by treatment with an ERK1/2 inhibitor. Using iontophoresis, we demonstrated that ET-1 is a potent, partially histamine-independent pruritogen in humans. Immunohistochemical evaluation of skin from prurigo nodularis patients confirmed an upregulation of the ET-1/ETAR/ECE-1/ERK1/2 axis in patients with chronic itch. Together, our data identify the neural peptidase ECE-1 as a negative regulator of itch on sensory nerves by directly regulating ET-1–induced pruritus in humans and mice. Furthermore, these results implicate the ET-1/ECE-1/ERK1/2 pathway as a therapeutic target to treat pruritus in humans. PMID:24812665

  8. Different frequencies of angiotensin-converting enzyme genotypes in older hypertensive individuals.

    PubMed Central

    Morris, B J; Zee, R Y; Schrader, A P

    1994-01-01

    The frequency of the D allele of an insertion/deletion (I/D) polymorphism of the angiotensin I-converting enzyme (ACE) gene has been reported to be elevated in myocardial infarction and other patients. We therefore hypothesized that death rate of DD individuals should be increased in the population as a whole and this should be evident as a decrease in DD frequency with age. This hypothesis was tested in 118 Caucasian subjects who were already at high risk of cardiovascular events by having severe, early onset, familial hypertension (HT). A group of 196 age-, sex- and body mass index-matched normotensives (NTs) was used as a control. In the NT group II, ID, and DD genotype frequencies were similar for different age groups. DD frequency was 0.42 in NTs, but in HTs was 0.28, 0.26, and 0.10 for the age groups < 50, 50-59, and > or = 60 yr, respectively. Corresponding D allele frequencies were 0.52, 0.46, and 0.40 in the respective age groups of HTs, compared with 0.61 in NTs (by chi 2-analysis, P = 0.1, 0.047, and 0.0006, respectively). In HTs aged > or = 60, DD frequency was only 14% of expected. Plasma ACE activity tracked similarly with I/D genotype in HTs (P = 0.027; n = 35) as in NTs (P = 0.0001; n = 94) and Michaelis constant was identical for DD and II. Neither blood pressure, body mass index, nor sex bore any relationship with I/D genotype. In conclusion, in a group of severely HT patients not selected for cardiac pathology, there appeared to be a marked, selective decrease, in subgroups of increasing age, in frequency of the ACE DD genotype. One possibility suggested by this data might be that DD increases risk of premature death, at least in HTs who have two HT parents. PMID:8083349

  9. Angiotensin-converting enzyme genotype and successful ascent to extreme high altitude.

    PubMed

    Thompson, Julian; Raitt, James; Hutchings, Lynn; Drenos, Fotios; Bjargo, Eirik; Loset, Are; Grocott, Mike; Montgomery, Hugh

    2007-01-01

    Interindividual variation in acclimatization to altitude suggests a genetic component, and several candidate genes have been proposed. One such candidate is a polymorphism in the angiotensin converting enzyme (ACE) gene, where the insertion (I-allele), rather than the deletion (D-allele), of a 287 base pair sequence has been associated with lower circulating and tissue ACE activity and has a greater than normal frequency among elite endurance athletes and, in a single study, among elite high altitude mountaineers. We tested the hypothesis that the I-allele is associated with successful ascent to the extreme high altitude of 8000 m. 141 mountaineers who had participated in expeditions attempting to climb an 8000-m peak completed a questionnaire and provided a buccal swab for ACE I/D genotyping. ACE genotype was determined in 139 mountaineers. ACE genotype distribution differed significantly between those who had successfully climbed beyond 8000 m and those who had not (p = 0.003), with a relative overrepresentation of the I-allele among the successful group (0.55 vs. 0.36 in successful vs. unsuccessful, respectively). The I-allele was associated with increased maximum altitudes achieved: 8079 +/- 947 m for DDs, 8107 +/- 653 m for IDs, and 8559 +/- 565 m for IIs (p = 0.007). There was no statistical difference in ACE genotype frequency between those who climbed to over 8000 m using supplementary oxygen and those who did not (p = 0.267). This study demonstrates an association between the ACE I-allele and successful ascent to over 8000 m.

  10. Urocortin 2 combined with angiotensin-converting enzyme inhibition in experimental heart failure.

    PubMed

    Rademaker, Miriam T; Charles, Christopher J; Nicholls, M Gary; Richards, A Mark

    2008-05-01

    Ucn2 (urocortin 2) is a recently discovered peptide with therapeutic potential in heart failure. As any new treatment is likely to be used in conjunction with standard ACEI (angiotensin-converting enzyme inhibitor) therapy, it is important that the combined effects of these agents are assessed. In the present study, we investigated the effects of Ucn2 and an ACEI (captopril) administered for 3 h, both separately and together, in eight sheep with pacing-induced heart failure. Ucn2 and captopril alone both increased CO (cardiac output; Ucn2>captopril) and decreased arterial pressure (captopril>Ucn2), left atrial pressure (Ucn2>captopril) and peripheral resistance (Ucn2=captopril) relative to controls. Compared with either treatment alone, combined treatment further improved CO and reduced peripheral resistance and cardiac preload, without inducing further falls in blood pressure. In contrast with the marked increase in plasma renin activity observed with captopril alone, Ucn2 administration reduced renin activity, whereas the combined agents resulted in intermediate renin levels. All active treatments decreased circulating levels of aldosterone (Ucn2+captopril>Ucn2=captopril), endothelin-1 and the natriuretic peptides (Ucn2+captopril=Ucn2>captopril), whereas adrenaline (epinephrine) fell only with Ucn2 (Ucn2+captopril=Ucn2), and vasopressin increased during captopril alone. Ucn2, both separately and in conjunction with captopril, increased urine output, sodium and creatinine excretion and creatinine clearance. Conversely, captopril administered alone adversely affected these renal indices. In conclusion, co-treatment with Ucn2 and an ACEI in heart failure produced significantly greater improvements in haemodynamics, hormonal profile and renal function than achieved by captopril alone. These results indicate that dual treatment with these two agents is beneficial.

  11. The novel nonapeptide acein targets angiotensin converting enzyme in the brain and induces dopamine release

    PubMed Central

    Neasta, Jérémie; Valmalle, Charlène; Coyne, Anne‐Claire; Carnazzi, Eric; Subra, Gilles; Galleyrand, Jean‐Claude; Gagne, Didier; M'Kadmi, Céline; Bernad, Nicole; Bergé, Gilbert; Cantel, Sonia; Marin, Philippe; Marie, Jacky; Banères, Jean‐Louis; Kemel, Marie‐Lou; Daugé, Valérie; Puget, Karine

    2016-01-01

    Background and Purpose Using an in‐house bioinformatics programme, we identified and synthesized a novel nonapeptide, H‐Pro‐Pro‐Thr‐Thr‐Thr‐Lys‐Phe‐Ala‐Ala‐OH. Here, we have studied its biological activity, in vitro and in vivo, and have identified its target in the brain. Experimental Approach The affinity of the peptide was characterized using purified whole brain and striatal membranes from guinea pigs and rats . Its effect on behaviour in rats following intra‐striatal injection of the peptide was investigated. A photoaffinity UV cross‐linking approach combined with subsequent affinity purification of the ligand covalently bound to its receptor allowed identification of its target. Key Results The peptide bound with high affinity to a single class of binding sites, specifically localized in the striatum and substantia nigra of brains from guinea pigs and rats. When injected within the striatum of rats, the peptide stimulated in vitro and in vivo dopamine release and induced dopamine‐like motor effects. We purified the target of the peptide, a ~151 kDa protein that was identified by MS/MS as angiotensin converting enzyme (ACE I). Therefore, we decided to name the peptide acein. Conclusion and Implications The synthetic nonapeptide acein interacted with high affinity with brain membrane‐bound ACE. This interaction occurs at a different site from the active site involved in the well‐known peptidase activity, without modifying the peptidase activity. Acein, in vitro and in vivo, significantly increased stimulated release of dopamine from the brain. These results suggest a more important role for brain ACE than initially suspected. PMID:27027724

  12. Effects of the angiotensin converting enzyme inhibitor enalapril compared with diuretic therapy in elderly hypertensive patients.

    PubMed

    Verza, M; Cacciapuoti, F; Spiezia, R; D'Avino, M; Arpino, G; D'Errico, S; Sepe, J; Varricchio, M

    1988-11-01

    The aim of this study was to evaluate the usefulness of the angiotensin converting enzyme (ACE) inhibitor enalapril in a group of 30 patients (mean age 73.3 years) with moderate hypertension and normal haematological and chemical parameters (170 +/- 8.1 mmHg systolic and 104 +/- 5.8 mmHg diastolic blood pressure), who were receiving diuretic therapy with chlorthalidone (12.5 mg/day). This therapy caused a significant decrease in systolic and diastolic blood pressure (to 165 +/- 6.7 and 98 +/- 4.7 mmHg, respectively; P less than 0.001) but it also induced hypokalaemia (3.04 +/- 0.7 mmol/l; P less than 0.001) and multiple (greater than 10/h) and complex premature ventricular depolarizations (2nd, 3rd and 4th Lown grade). Enalapril treatment (5 mg/day for 5 days and 10 mg thereafter) was added to the diuretic therapy and after 2 months a further decrease in blood pressure was observed (to 158 +/- 5.6 mmHg systolic, P less than 0.001; 87.2 +/- 5.0 mmHg diastolic, P less than 0.001). Moreover, there was a significant reduction in the mean heart rate (from 79 to 72 beats/min, P less than 0.005) and an increase in serum potassium (to 4.19 +/- 0.2 mmol/l; P less than 0.001). In 80% of patients a 24-h dynamic electrocardiogram showed a significant reduction in both the number and complexity of premature ventricular depolarizations. Our findings suggest that ACE inhibitors can be useful in patients developing hypokalaemia during therapy. However, we are not yet able to explain the beneficial effects of enalapril in decreasing the frequency of premature ventricular depolarizations.

  13. Angiotensin converting enzyme 2: A new important player in the regulation of glycemia

    PubMed Central

    Chhabra, Kavaljit H.; Chodavarapu, Harshita; Lazartigues, Eric

    2015-01-01

    In spite of the novel anti-diabetic drugs available on the market, type 2 diabetes mellitus (T2DM) affects nearly 25 million people in the USA and causes about 5% of all deaths globally each year. Given the rate and proportion by which T2DM is affecting human beings, it is indispensable to identify new therapeutic targets that can control the disease. Recent pre-clinical and clinical studies suggest that attenuating the activity of the renin-angiotensin system (RAS) could improve glycemia in diabetic patients. Angiotensin converting enzyme 2 (ACE2) counteracts RAS over-activity by degrading Ang-II, a vasoconstrictor, to Ang-(1-7) which is a vasodilator. A decrease in ACE2 and an increase in ADAM17-mediated shedding activity have been observed with the progression of T2DM suggesting the importance of this mechanism in the disease. Indeed, restoration of ACE2 improves glycemia in db/db and Ang-II-infused mice. The beneficial effects of ACE2 can be attributed to reduced oxidative stress and ADAM17 expression in the islets of Langerhans in addition to the improvement of blood flow to the β-cells. The advantage of ACE2 over other RAS blockers is that ACE2 not only counteracts the negative effects of Ang-II but also increases Ang-(1-7)/MasR [a receptor through which Ang-(1-7) produces its actions] signaling in the cells. Increased Ang-(1-7)/MasR signaling has been reported to improve insulin sensitivity and glycemia in diabetic animals. Altogether, ACE2/Ang-(1-7)/MasR axis of the RAS appears to be protective in T2DM and strategies to restore ACE2 levels in the disease seem to be a promising therapy for Ang-II-mediated T2DM. PMID:23893738

  14. Angiotensin converting enzyme 2: a new important player in the regulation of glycemia.

    PubMed

    Chhabra, Kavaljit H; Chodavarapu, Harshita; Lazartigues, Eric

    2013-09-01

    In spite of the novel antidiabetic drugs available on the market, type 2 diabetes mellitus (T2DM) affects nearly 25 million people in the USA and causes about 5% of all deaths globally each year. Given the rate and proportion by which T2DM is affecting human beings, it is indispensable to identify new therapeutic targets that can control the disease. Recent preclinical and clinical studies suggest that attenuating the activity of the renin-angiotensin system (RAS) could improve glycemia in diabetic patients. Angiotensin-converting enzyme 2 (ACE2) counteracts RAS overactivity by degrading angiotensin-II (Ang-II), a vasoconstrictor, to Ang-(1-7) which is a vasodilator. A decrease in ACE2 and an increase in A disintegrin and metalloproteinase (ADAM17)-mediated shedding activity have been observed with the progression of T2DM, suggesting the importance of this mechanism in the disease. Indeed, restoration of ACE2 improves glycemia in db/db and Ang-II-infused mice. The beneficial effects of ACE2 can be attributed to reduced oxidative stress and ADAM17 expression in the islets of Langerhans in addition to the improvement of blood flow to the β-cells. The advantage of ACE2 over other RAS blockers is that ACE2 not only counteracts the negative effects of Ang-II but also increases Ang-(1-7)/Mas receptor (MasR) [a receptor through which Ang-(1-7) produces its actions] signaling in the cells. Increased Ang-(1-7)/MasR signaling has been reported to improve insulin sensitivity and glycemia in diabetic animals. Altogether, ACE2/Ang-(1-7)/MasR axis of the RAS appears to be protective in T2DM and strategies to restore ACE2 levels in the disease seem to be a promising therapy for Ang-II-mediated T2DM.

  15. Angiotensin I Converting Enzyme Inhibitory Peptides Derived from Phycobiliproteins of Dulse Palmaria palmata

    PubMed Central

    Furuta, Tomoe; Miyabe, Yoshikatsu; Yasui, Hajime; Kinoshita, Yasunori; Kishimura, Hideki

    2016-01-01

    We examined the inhibitory activity of angiotensin I converting enzyme (ACE) in protein hydrolysates from dulse, Palmaria palmata. The proteins extracted from dulse were mainly composed of phycoerythrin (PE) followed by phycocyanin (PC) and allophycocyanin (APC). The dulse proteins showed slight ACE inhibitory activity, whereas the inhibitory activity was extremely enhanced by thermolysin hydrolysis. The ACE inhibitory activity of hydrolysates was hardly affected by additional pepsin, trypsin and chymotrypsin treatments. Nine ACE inhibitory peptides (YRD, AGGEY, VYRT, VDHY, IKGHY, LKNPG, LDY, LRY, FEQDWAS) were isolated from the hydrolysates by reversed-phase high-performance liquid chromatography (HPLC), and it was demonstrated that the synthetic peptide LRY (IC50: 0.044 μmol) has remarkably high ACE inhibitory activity. Then, we investigated the structural properties of dulse phycobiliproteins to discuss the origin of dulse ACE inhibitory peptides. Each dulse phycobiliprotein possesses α-subunit (Mw: 17,477–17,638) and β-subunit (Mw: 17,455–18,407). The sequences of YRD, AGGEY, VYRT, VDHY, LKNPG and LDY were detected in the primary structure of PE α-subunit, and the LDY also exists in the APC α- and β-subunits. In addition, the LRY sequence was found in the β-subunits of PE, PC and APC. From these results, it was suggested that the dulse ACE inhibitory peptides were derived from phycobiliproteins, especially PE. To make sure the deduction, we carried out additional experiment by using recombinant PE. We expressed the recombinant α- and β-subunits of PE (rPEα and rPEβ, respectively), and then prepared their peptides by thermolysin hydrolysis. As a result, these peptides showed high ACE inhibitory activities (rPEα: 94.4%; rPEβ: 87.0%). Therefore, we concluded that the original proteins of dulse ACE inhibitory peptides were phycobiliproteins. PMID:26861357

  16. Inhibitors of angiotensin-converting enzyme modulate mitosis and gene expression in pancreatic cancer cells

    SciTech Connect

    Reddy, M.K.; Baskaran, K.; Molteni, A.

    1995-12-01

    The angiotensin-converting enzyme (ACE) inhibitor captopril inhibits mitosis in several cell types that contain ACE and renin activity. In the present study, we evaluated the effect of the ACE inhibitors captopril and CGS 13945 (10{sup {minus}8} to 10{sup {minus}2}M) on proliferation and gene expression in hamster pancreatic duct carcinoma cells in culture. These cells lack renin and ACE activity. Both ACE inhibitors produced a dose-dependent reduction in tumor cell proliferation within 24 hr. Captopril at a concentration of 0.36 mM and CGS 13945 at 150 {mu}M decreased cellular growth rate to approximately half that of the control. Neither drug influenced the viability or the cell cycle distribution of the tumor cells. Slot blot analysis of mRNA for four genes, proliferation associated cell nuclear antigen (PCNA), K-ras, protein kinase C-{Beta} (PKC-{Beta}) and carbonic anhydrase II (CA II) was performed. Both ACE inhibitors increased K-ras expression by a factor of 2, and had no effect on CA II mRNA levels. Captopril also lowered PCNA by 40% and CGS 13945 lowered PKC-{Beta} gene expression to 30% of the control level. The data demonstrate that ACE inhibitors exhibit antimitotic activity and differential gene modulation in hamster pancreatic duct carcinoma cells. The absence of renin and ACE activity in these cells suggests that the antimitotic action of captopril and CGS 13945 is independent of renin-angiotensin regulation. The growth inhibition may occur through downregulation of growth-related gene expression. 27 refs., 5 figs.

  17. Angiotensin I-converting enzyme inhibitory peptides generated from in vitro gastrointestinal digestion of pork meat.

    PubMed

    Escudero, Elizabeth; Sentandreu, Miguel Angel; Arihara, Keizo; Toldrá, Fidel

    2010-03-10

    The main purpose of this work was to study the generation of Angiotensin I-converting enzyme inhibitory (ACEI) peptides after gastrointestinal digestion of pork meat by the action of pepsin and pancreatin at simulated gut conditions. The hydrolysate was further subjected to reverse phase chromatography in order to separate the fractions with ACEI activity. Using MALDI-TOF/TOF mass spectrometry, 12 peptides were identified in these fractions. It is worth highlighting the novel peptides ER, KLP, and RPR with IC(50) values of 667 microM, 500 microM, and 382 microM, respectively. Results obtained by MALDI-TOF/TOF mass spectrometry were complemented by a second approach consisting of the analysis of the hydrolysate directly by nanoLC-ESI-MS/MS followed by a study of the obtained sequences and comparison with known ACEI peptide sequences. By using these two approaches, a total of 22 peptides were selected for its synthesis and further in vitro assay of ACEI activity. The strongest ACE inhibition was observed for peptide KAPVA (IC(50) = 46.56 microM) followed by the sequence PTPVP (IC(50) = 256.41 microM). Sequence similarity searches revealed that these two peptides derive from muscle titin, constituting the first identified ACEI peptides coming from this protein. This is also the first time that ACEI sequences MYPGIA and VIPEL have been reported. Other identified and synthesized sequences showed less ACEI activity. The obtained results evidence the potential of pork meat proteins as a source of antihypertensive peptides after gastrointestinal digestion.

  18. Genetic Variants of Angiotensin-Converting Enzyme Are Linked to Autism: A Case-Control Study

    PubMed Central

    Firouzabadi, Negar; Erfani, Nasrallah; Fathi, Farshid; Bazrafkan, Mozhdeh; Bahramali, Ehsan

    2016-01-01

    Background Autism is a disease of complex nature with a significant genetic component. The importance of renin-angiotensin system (RAS) elements in cognition and behavior besides the interaction of angiotensin II (Ang II), the main product of angiotensin-converting enzyme (ACE), with neurotransmitters in CNS, especially dopamine, proposes the involvement of RAS in autism. Since the genetic architecture of autism has remained elusive, here we postulated that genetic variations in RAS are associated with autism. Methods Considering the relation between the three polymorphisms of ACE (I/D, rs4343 and rs4291) with the level of ACE activity, we have investigated this association with autism, in a case-control study. Genotype and allele frequencies of polymorphisms were determined in DNAs extracted from venous blood of 120 autistic patients and their age and sex-matched healthy controls, using polymerase chain reaction (PCR) and PCR–restriction fragment length polymorphism (PCR–RFLP) methods. Results There were strong associations between both DD genotype of ACE I/D and the D allele, with autism (P = 0.006, OR = 2.9, 95% CI = 1.64–5.13 and P = 0.006, OR = 2.18, 95% CI = 1.37–3.48 respectively). Furthermore, a significant association between the G allele of rs4343 and autism was observed (P = 0.006, OR = 1.84, 95%CI = 1.26–2.67). Moreover, haplotype analysis revealed an association between DTG haplotype and autism (P = 0.008). Conclusion Our data suggests the involvement of RAS genetic diversity in increasing the risk of autism. PMID:27082637

  19. Identification of positive and negative transcriptional regulatory elements of the rabbit angiotensin-converting enzyme gene.

    PubMed Central

    Goraya, T Y; Kessler, S P; Kumar, R S; Douglas, J; Sen, G C

    1994-01-01

    The two tissue-specific mRNAs encoding the isozymes of rabbit angiotensin-converting enzyme (ACE) are generated from the same gene by alternative choice of two transcription initiation sites 5.7 kb apart. In the current study, we have characterized the regulatory sites controlling the transcription of the larger pulmonary isozyme mRNA. For this purpose, reporter genes driven by varying lengths of upstream region of the ACE gene were transfected into ACE-producing cells. Our results demonstrated that the transcription of this gene is primarily driven by positive elements within the first 274 bp DNA upstream of the transcription initiation site. The reporter gene driven by this region was expressed in two ACE-producing cells but not in two ACE-non-producing cells thereby establishing its tissue specificity. Our experiments also revealed the existence of a strong negative element located between -692 and -610 positions. This element suppressed the expression of the reporter gene in a dose-dependent and position and orientation-independent fashion thus suggesting that it is a true silencer element. It could also repress the expression of a reporter gene driven by the heterologous strong promoter of the beta-actin gene. The repressing effects of the negative element could be partially overcome by cotransfecting the isolated negative element along with the reporter gene containing the negative element. This result was possibly due to the functional removal of a limiting trans-acting factor which binds to this element. Electrophoretic mobility shift assays revealed that the negative element can form several complexes with proteins present in the nuclear extract of an ACE-producing cell line. At least part of the negative element is strongly conserved in the upstream regions of the human and mouse ACE genes. Images PMID:8165133

  20. Liquid chromatographic determination of hippuric acid for the evaluation of ethacrynic acid as angiotensin converting enzyme inhibitor.

    PubMed

    Mehanna, A S; Dowling, M

    1999-05-01

    A rapid, simple and interference-free method is described to evaluate the inhibitory effects of organic compounds on the activity of angiotensin converting enzyme irrespective of their acid-base properties. The assay is based on the high performance liquid chromatographic separation of the synthetic substrate hippuryl-L-histidyl-L-leucine, the hydrolysis product hippuric acid and the test compound. Using the new method, the diuretic drug ethacrynic acid was found to act as an inhibitor for the enzyme in a non competitive mode.

  1. In silico analysis and molecular docking studies of potential angiotensin-converting enzyme inhibitor using quercetin glycosides

    PubMed Central

    Muhammad, Syed Aun; Fatima, Nighat

    2015-01-01

    The purpose of this study was to analyze the inhibitory action of quercetin glycosides by computational docking studies. For this, natural metabolite quercetin glycosides isolated from buckwheat and onions were used as ligand for molecular interaction. The crystallographic structure of molecular target angiotensin-converting enzyme (ACE) (peptidyl-dipeptidase A) was obtained from PDB database (PDB ID: 1O86). Enalapril, a well-known brand of ACE inhibitor was taken as the standard for comparative analysis. Computational docking analysis was performed using PyRx, AutoDock Vina option based on scoring functions. The quercetin showed optimum binding affinity with a molecular target (angiotensin-converting-enzyme) with the binding energy of −8.5 kcal/mol as compared to the standard (−7.0 kcal/mol). These results indicated that quercetin glycosides could be one of the potential ligands to treat hypertension, myocardial infarction, and congestive heart failure. PMID:26109757

  2. Angiotensin-converting enzyme inhibitors and beta-blockers in cardiac asymptomatic patients with Duchenne muscular dystrophy.

    PubMed

    Fayssoil, A

    2010-01-01

    Duchenne muscular dystrophy (DMD) is an X-linkedrecessive disorder caused by the absence of dystrophin. Cardiac dysfunction is a classical complication in this disease. Most DMD patients remain asymptomatic for years in spite of the progression of cardiac dysfunction because of their limited daily activities. Angiotensin-converting enzyme inhibitors and beta-blockers may delay the onset and the progression of cardiac dysfunction and have to be recommended earlier in this disease.

  3. Molecular identification of tuliposide B-converting enzyme: a lactone-forming carboxylesterase from the pollen of tulip.

    PubMed

    Nomura, Taiji; Murase, Tatsunori; Ogita, Shinjiro; Kato, Yasuo

    2015-07-01

    6-Tuliposides A (PosA) and B (PosB), which are the major secondary metabolites in tulip (Tulipa gesneriana), are enzymatically converted to the antimicrobial lactonized aglycons, tulipalins A (PaA) and B (PaB), respectively. We recently identified a PosA-converting enzyme (TCEA) as the first reported member of the lactone-forming carboxylesterases. Herein, we describe the identification of another lactone-forming carboxylesterase, PosB-converting enzyme (TCEB), which preferentially reacts with PosB to give PaB. This enzyme was isolated from tulip pollen, which showed high PosB-converting activity. Purified TCEB exhibited greater activity towards PosB than PosA, which was contrary to that of the TCEA. Novel cDNA (TgTCEB1) encoding the TCEB was isolated from tulip pollen. TgTCEB1 belonged to the carboxylesterase family and was approximately 50% identical to the TgTCEA polypeptides. Functional characterization of the recombinant enzyme verified that TgTCEB1 catalyzed the conversion of PosB to PaB with an activity comparable with the native TCEB. RT-qPCR analysis of each part of plant revealed that TgTCEB1 transcripts were limited almost exclusively to the pollen. Furthermore, the immunostaining of the anther cross-section using anti-TgTCEB1 polyclonal antibody verified that TgTCEB1 was specifically expressed in the pollen grains, but not in the anther cells. N-terminal transit peptide of TgTCEB1 was shown to function as plastid-targeted signal. Taken together, these results indicate that mature TgTCEB1 is specifically localized in plastids of pollen grains. Interestingly, PosB, the substrate of TgTCEB1, accumulated on the pollen surface, but not in the intracellular spaces of pollen grains.

  4. Role of angiotensin converting enzyme in the vascular effects of an endopeptidase 24.15 inhibitor.

    PubMed Central

    Telford, S E; Smith, A I; Lew, R A; Perich, R B; Madden, A C; Evans, R G

    1995-01-01

    1. We investigated the role of angiotensin converting enzyme (ACE) in the cardiovascular effects of N-[1-(R,S)-carboxy-3-phenylpropyl]-Ala-Ala-Tyr-p-aminobenzoate (cFP), a peptidase inhibitor selective for metalloendopeptidase (EP) E.C. 3.4.24.15. 2. In conscious rabbits, cFP (5 mg kg-1, i.v.) markedly slowed the degradation of [3H]-bradykinin, potentiated the depressor response to right atrial administration of bradykinin (10-1000 ng kg-1), and inhibited the pressor response to right atrial angiotensin I (10-100 ng kg-1). In each of these respects, the effects of cFP were indistinguishable from those of the ACE inhibitor, captopril (0.5 mg plus 10 mg kg-1h-1 i.v.). Furthermore, the effects of combined administration of cFP and captopril were indistinguishable from those of captopril alone. 3. In experimentally naive anaesthetized rats, cFP administration (9.3 mg kg-1, i.v.) was followed by a moderate but sustained fall in arterial pressure of 13 mmHg. However, in rats pretreated with bradykinin (50 micrograms kg-1) a more pronounced fall of 30 mmHg was observed. Captopril (5 mg kg-1) had similar hypotensive effects to those of cFP, and cFP had no effect when it was administered after captopril. 4. CFP displaced the binding of [125I]-351A (the p-hydroxybenzamidine derivative of lisinopril) from preparations of rat plasma ACE and solubilized lung membrane ACE (KD = 1.2 and 0.14 microM respectively), and inhibited rat plasma ACE activity (KI = 2.4 microM). Addition of phosphoramidon (10 microM), an inhibitor of a range of metalloendopeptidases, including neutral endopeptidase (E.C.3.4.24.11), markedly reduced the potency of cFP in these systems.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:7620708

  5. Cardiac-restricted angiotensin-converting enzyme overexpression causes conduction defects and connexin dysregulation

    PubMed Central

    Kasi, Vijaykumar S.; Xiao, Hong D.; Shang, Lijuan L.; Iravanian, Shahriar; Langberg, Jonathan; Witham, Emily A.; Jiao, Zhe; Gallego, Carlos J.; Bernstein, Kenneth E.; Dudley, Samuel C.

    2011-01-01

    Renin-angiotensin (RAS) system activation is associated with an increased risk of sudden death. Previously, we used cardiac-restricted angiotensin-converting enzyme (ACE) overexpression to construct a mouse model of RAS activation. These ACE 8/8 mice die prematurely and abruptly. Here, we have investigated cardiac electrophysiological abnormalities that may contribute to early mortality in this model. In ACE 8/8 mice, surface ECG voltages are reduced. Intracardiac electrograms showed atrial and ventricular potential amplitudes of 11% and 24% compared with matched wild-type (WT) controls. The atrioventricular (AV), atrio-Hisian (AH), and Hisian-ventricular (HV) intervals were prolonged 2.8-, 2.6-, and 3.9-fold, respectively, in ACE 8/8 vs. WT mice. Various degrees of AV nodal block were present only in ACE 8/8 mice. Intracardiac electrophysiology studies demonstrated that WT and heterozygote (HZ) mice were noninducible, whereas 83% of ACE 8/8 mice demonstrated ventricular tachycardia with burst pacing. Atrial connexin 40 (Cx40) and connexin 43 (Cx43) protein levels, ventricular Cx43 protein level, atrial and ventricular Cx40 mRNA abundances, ventricular Cx43 mRNA abundance, and atrial and ventricular cardiac Na+ channel (Scn5a) mRNA abundances were reduced in ACE 8/8 compared with WT mice. ACE 8/8 mice demonstrated ventricular Cx43 dephosphorylation. Atrial and ventricular L-type Ca2+ channel, Kv4.2 K+ channel α-subunit, and Cx45 mRNA abundances and the peak ventricular Na+ current did not differ between the groups. In isolated heart preparations, a connexin blocker, 1-heptanol (0.5 mM), produced an electrophysiological phenotype similar to that seen in ACE 8/8 mice. Therefore, cardiac-specific ACE overexpression resulted in changes in connexins consistent with the phenotype of low-voltage electrical activity, conduction defects, and induced ventricular arrhythmia. These results may help explain the increased risk of arrhythmia in states of RAS activation such as

  6. Multifunctional gold nanoparticles for targeted imaging of angiotensin converting enzyme design, characterization, and application

    NASA Astrophysics Data System (ADS)

    Ghann, William Emmanuel

    Cardiovascular diseases (CVD) are the leading cause of morbidity and mortality in the United States with approximately one in every three death being attributed to these diseases. The overarching problem with heart diseases is that once a person has suffered from an attack, there is a high likelihood of a recurrent attack. According to the American Heart Association, approximately 785,000 Americans per year suffer from heart attacks for the first time and about half of the aforementioned experience an ensuing attack. The second attack is often fatal, and therefore relapse prevention is crucial. One of the possible ways of averting the recurrence of such an attack is through the precise monitoring of the preceding biomarkers or risk indicators. This project encompasses the design, synthesis, characterization, and application of nanoparticle-based contrast agents that can potentially be used in the monitoring of the reemergence of a biomarker expressed after a person has suffered myocardial infarction. The overexpression of this biomarker, angiotensin converting enzyme (ACE), is also associated with development of cardiac and pulmonary fibrosis. To this end, highly concentrated gold nanoparticles have been synthesized and conjugated to Lisinopril, an ACE inhibitor, for the molecular imaging of ACE using X-ray CT. Various stabilities studies were conducted to verify the resistance of this gold nanoprobe in biological relevant media. They have also been successfully used in X-ray computed tomography to visualize tissue ACE and thus render them potentially versatile in the monitoring of cardiovascular diseases. An MRI tag was also conjugated to the gold nanoparticle affording the opportunity for bimodal imaging of ACE. This contrast agent could further be used for the quantification using K-edge CT of the relationship between the amount of the said marker and its role in predicting the possibility of a successive heart attack. The prepared nanoparticle-based contrast

  7. Left ventricular hypertrophy among black hypertensive patients: focusing on the efficacy of angiotensin converting enzyme inhibitors

    PubMed Central

    2014-01-01

    Background Left ventricular hypertrophy (LVH) is an independent cardiovascular risk factor in patients with essential hypertension. The main objective of this study was to assess the echocardiographic prevalence of left ventricular hypertrophy in patients with hypertension, its risk factors and effect of antihypertensive drugs on its prevalence. Methods A hospital based cross sectional study was conducted on 200 hypertensive patients on treatment in southwest Ethiopia. A pretested structured questionnaire was used to collect data from participants and their clinical records. Blood pressure and anthropometric measurements were taken according to recommended standards. Left ventricular mass was measured by transthoracic echocardiography. Associations between categorical variables were assessed using chi-square test and odds ratio with 95% confidence interval. Logistic regression model was done to identify risks factors of LVH. P values of < 0.05 were considered as statistically significant. Results The mean age, systolic blood pressure, diastolic blood pressure and body mass index were 55.7 ± 11.3 years, 139.2 ± 7.7 mmHg, 89.2 ± 5.7 mmHg and 24.2 ± 3.4 Kg/m2 respectively. The overall prevalence of LVH among these study subjects was 52%. Age ≥50 years (OR: 3.49, 95% CI 1.33-9.14, P = 0.011), female gender (OR: 7.69, 95% CI 3.23-20.0, P < 0.001), systolic blood pressure ≥140 mmHg (OR: 2.85, 95% CI 1.27-6.41, P = 0.011), and duration of hypertension (OR: 3.59, 95% CI 1.47-8.76, P = 0.005) were independent predictors of left ventricular hypertrophy. Angiotensin converting enzyme (ACE) inhibitors were the only antihypertensive drugs associated with lower risk of left ventricular hypertrophy (OR: 0.08, 95% CI 0.03-0.19, p < 0.001). Conclusions Left ventricular hypertrophy was found to be highly prevalent in hypertensive patients in Ethiopia. ACE inhibitors were the only antihypertensive drugs associated with reduced risk

  8. Role of Protein Kinase C in Endothelin Converting Enzyme-1 trafficking and shedding from endothelial cells

    SciTech Connect

    Kuruppu, Sanjaya; Tochon-Danguy, Natalie; Ian Smith, A.

    2010-07-23

    Research highlights: {yields} PKC activation increases the trafficking of ECE-1 to the cell surface. {yields} This in turn leads to an increase in the amount of ECE-1 shed. {yields} Only the catalytically active C-terminal region is shed from the cell surface. -- Abstract: This study aimed to determine the consequences of Protein Kinase C (PKC) mediated Endothelin Converting Enzyme-1 (ECE-1) phosphorylation and its relationship to ECE-1 expression and shedding. The proteins on the surface of EA.hy926 cells were labelled with EZ-Link NHS-SS-Biotin both prior to (control) and following stimulation by 2 {mu}M phorbol 12-myristate 13-acetate (PMA) which activates PKC. The biotinylated proteins were isolated using neutravidin beads, resolved by gel electrophoresis and analysed by western blotting using anti-ECE-1 antibodies. Significant increase in ECE-1 expression at the cell surface was observed following stimulation by PMA, compared to unstimulated control cells (170 {+-} 32.3% of control, n = 5). The ECE-1 activity (expressed as {mu}M substrate cleaved/min) was determined by monitoring the cleavage of a quenched fluorescent substrate. The specificity of cleavage was confirmed using the ECE-1 inhibitor (CGS35066). The stimulation of cells by PMA (1 {mu}M, 6 h) significantly increased the ECE-1 activity (0.28 {+-} 0.02; n = 3) compared to the control (0.07 {+-} 0.02; n = 3). This increase was prevented by prior incubation with the PKC inhibitor bisindolymaleimide (BIM; 2 {mu}M for 1 h; 0.10 {+-} 0.01; n = 3). Treatment with PMA also increased the activity of ECE-1 in the media (0.18 {+-} 0.01; n = 3) compared to control (0.08 {+-} 0.01; n = 3). In addition, this study confirmed by western immunoblotting that only the extracellular region of ECE-1 is released from the cell surface. These data indicate for the first time that PKC activation induces the trafficking and shedding of ECE to and from the cell surface, respectively.

  9. Substrate phosphorylation affects degradation and interaction to endopeptidase 24.15, neurolysin, and angiotensin-converting enzyme.

    PubMed

    Machado, M F M; Cunha, F M; Berti, D A; Heimann, A S; Klitzke, C F; Rioli, V; Oliveira, V; Ferro, E S

    2006-01-13

    Recent findings from our laboratory suggest that intracellular peptides containing putative post-translational modification sites (i.e., phosphorylation) could regulate specific protein interactions. Here, we extend our previous observations showing that peptide phosphorylation changes the kinetic parameters of structurally related endopeptidase EP24.15 (EC 3.4.24.15), neurolysin (EC 3.4.24.16), and angiotensin-converting enzyme (EC 3.4.15.1). Phosphorylation of peptides that are degraded by these enzymes leads to reduced degradation, whereas phosphorylation of peptides that interacted as competitive inhibitors of these enzymes alters only the K(i)'s. These data suggest that substrate phosphorylation could be one of the mechanisms whereby some intracellular peptides would escape degradation and could be regulating protein interactions within cells.

  10. Purification and characterization of a tuliposide-converting enzyme from bulbs of Tulipa gesneriana.

    PubMed

    Kato, Yasuo; Shoji, Kazuaki; Ubukata, Makoto; Shigetomi, Kengo; Sato, Yukio; Nakajima, Noriyuki; Ogita, Shinjiro

    2009-08-01

    An enzyme that catalyzes the stoichiometric conversion of 6-tuliposide into tulipalin was purified and characterized from bulbs of Tulipa gesneriana. The enzyme appeared to be a dimer, the relative molecular mass (Mr) of each subunit being 34,900; it had maximum activity and stability at neutral pH and moderate temperature. The enzyme preferentially acted on such glucose esters as 6-tuliposides, and to a lesser extent on p-nitrophenylacetate.

  11. Utilization of peptide carrier system to improve intestinal absorption: targeting prolidase as a prodrug-converting enzyme

    NASA Technical Reports Server (NTRS)

    Bai, J. P.; Hu, M.; Subramanian, P.; Mosberg, H. I.; Amidon, G. L.

    1992-01-01

    The feasibility of targeting prolidase as a peptide prodrug-converting enzyme has been examined. The enzymatic hydrolysis by prolidase of substrates for the peptide transporter L-alpha-methyldopa-pro and several dipeptide analogues without an N-terminal alpha-amino group (phenylpropionylproline, phenylacetylproline, N-benzoylproline, and N-acetylproline) was investigated. The Michaelis-Menten parameters Km and Vmax for L-alpha-methyldopa-pro are 0.09 +/- 0.02 mM and 3.98 +/- 0.25 mumol/min/mg protein, respectively. However, no hydrolysis of the dipeptide analogues without an N-terminal alpha-amino group is observed, suggesting that an N-terminal alpha-amino group is required for prolidase activity. These results demonstrate that prolidase may serve as a prodrug-converting enzyme for the dipeptide-type prodrugs, utilizing the peptide carrier for transport of prodrugs into the mucosal cells and prolidase, a cytosolic enzyme, to release the drug. However, a free alpha-amino group appears to be necessary for prolidase hydrolysis.

  12. Angiotensin I-converting enzyme inhibitory peptide derived from glycinin, the 11S globulin of soybean (Glycine max).

    PubMed

    Mallikarjun Gouda, K G; Gowda, Lalitha R; Rao, A G Appu; Prakash, V

    2006-06-28

    Angiotensin I-converting enzyme (ACE), a dipeptidyl carboxypeptidase, catalyzes the conversion of Angiotensin I to the potent vasoconstrictor Angiotensin II and plays an important physiological role in regulating blood pressure. Inhibitors of angiotensin 1-converting enzyme derived from food proteins are utilized for pharmaceuticals and physiologically functional foods. ACE inhibitory properties of different enzymatic hydrolysates of glycinin, the major storage protein of soybean, have been demonstrated. The IC50 value for the different enzyme digests ranges from 4.5 to 35 microg of N2. The Protease P hydrolysate contained the most potent suite of ACE inhibitory peptides. The ACE inhibitory activity of the Protease P hydrolysate after fractionation by RP-HPLC and ion-pair chromatography was ascribed to a single peptide. The peptide was homogeneous as evidenced by MALDI-TOF and identified to be a pentapeptide. The sequence was Val-Leu-Ile-Val-Pro. This peptide was synthesized using solid-phase FMOC chemistry. The IC50 for ACE inhibition was 1.69 +/- 0.17 microM. The synthetic peptide was a potent competitive inhibitor of ACE with a Ki of 4.5 +/- 0.25 x 10(-6) M. This peptide was resistant to digestion by proteases of the gastrointestinal tract. The antihypertensive property of this peptide derived from glycinin might find importance in the development of therapeutic functional foods.

  13. In vitro modeling of angiotensin-converting enzyme inhibitor's absorption with chromatographic retention data and selected molecular descriptors.

    PubMed

    Odović, Jadranka; Marković, Bojan; Vladimirov, Sote; Karljiković-Rajić, Katarina

    2014-03-15

    Set of nine angiotensin-converting enzyme inhibitors (enalapril, quinapril, fosinopril, lisinopril, cilazapril, ramipril, benazepril, perindopril and moexipril) were studied to evaluate the correlation between their intestinal absorption and salting-out thin-layer chromatography hydrophobicity parameters (RM(0) or C0) obtained by ascending technique applying four different salts, (NH4)2SO4, NH4NO3, NH4Cl and NaCl as mobile phases. The best correlations between KOWWIN logP and both hydrophobicity parameters, RM(0) and C0, (R(2)>0.850) were observed for NaCl (1.0-3.0M) while the lowest R(2) was obtained for (NH4)2SO4 (0.649 and 0.427, respectively) due to highest salting-out effect of (NH4)2SO4. The effect of selected inorganic salts in the salting-out mobile phases, on the solutes solubility and retention was evaluated. The topological polar surface area should be selected as independent variable (only this molecular descriptor showed low correlation with chromatographic hydrophobicity parameters) for multiple linear regression analysis, to obtain reliable correlation between angiotensin-converting enzyme inhibitor's intestinal absorption data and salting-out thin-layer chromatograpic hydrophobicity parameters. These correlations provide R(2)=0.823 for RM(0) or R(2)=0.799 for C0 indicating good relationship between predicted and literature available intestinal absorption (ranged from 22% to 70%) of investigated angiotensin-converting enzyme inhibitors. The proposed in vitro model was checked with three in addition experimentally analyzed drugs, zofenopril, trandolapril and captoril. The satisfactory absorption prediction was obtained for zofenopril and trandolapril, while divergence established for captopril resulted from considerably different structure.

  14. Screening the Brazilian flora for antihypertensive plant species for in vitro angiotensin-I-converting enzyme inhibiting activity.

    PubMed

    Castro Braga, F; Wagner, H; Lombardi, J A; de Oliveira, A B

    2000-06-01

    The evaluation of several antihypertensive activity of Brazilian plant species was performed using in vitro inhibition of the angiotensin I-converting enzyme (ACE). Nineteen species belonging to 13 families were investigated. Plants were selected based on their use as diuretics and on a chemosystematic consideration. Extracts of the following species presented the highest ACE inhibition rate, at concentrations of 0.33 mg/ml: Ouratea semiserrata (Mart. & Nees) Engl. stems (68%), Cuphea cartagenesis (Jacq.) Macbride leaves (50%) and Mansoa hirsuta DC. leaves (54%). Some hypotheses about the nature of the compounds that may be responsible for the activity of these species are discussed in the paper.

  15. Racial differences in blood pressure response to angiotensin-converting enzyme inhibitors in children: a meta-analysis.

    PubMed

    Li, J S; Baker-Smith, C M; Smith, P B; Hasselblad, V; Murphy, M D; Califf, R M; Benjamin, D K

    2008-09-01

    Angiotensin-converting enzyme (ACE) inhibitors are frequently used to treat hypertension in children.(1) ACE inhibitors alter the balance between the vasoconstrictive, salt-retentive, and cardiac hypertrophic properties of angiotensin II and the vasodilatory and natriuretic properties of bradykinin; they also alter the metabolism of other vasoactive substances.(2) Through these mechanisms, ACE inhibitors decrease systemic vascular resistance and promote natriuresis without increasing heart rate. This study evaluated the results of six trials of ACE inhibitors in children, using meta-analytic techniques to estimate the effect of race on blood pressure response.

  16. Angiotensin I-converting enzyme (ACE) inhibitory activity and ACE inhibitory peptides of salmon (Salmo salar) protein hydrolysates obtained by human and porcine gastrointestinal enzymes.

    PubMed

    Darewicz, Małgorzata; Borawska, Justyna; Vegarud, Gerd E; Minkiewicz, Piotr; Iwaniak, Anna

    2014-08-13

    The objectives of the present study were two-fold: first, to detect whether salmon protein fractions possess angiotensin I-converting enzyme (ACE) inhibitory properties and whether salmon proteins can release ACE inhibitory peptides during a sequential in vitro hydrolysis (with commercial porcine enzymes) and ex vivo digestion (with human gastrointestinal enzymes). Secondly, to evaluate the ACE inhibitory activity of generated hydrolysates. A two-step ex vivo and in vitro model digestion was performed to simulate the human digestion process. Salmon proteins were degraded more efficiently by porcine enzymes than by human gastrointestinal juices and sarcoplasmic proteins were digested/hydrolyzed more easily than myofibrillar proteins. The ex vivo digested myofibrillar and sarcoplasmic duodenal samples showed IC50 values (concentration required to decrease the ACE activity by 50%) of 1.06 and 2.16 mg/mL, respectively. The in vitro hydrolyzed myofibrillar and sarcoplasmic samples showed IC50 values of 0.91 and 1.04 mg/mL, respectively. Based on the results of in silico studies, it was possible to identify 9 peptides of the ex vivo hydrolysates and 7 peptides of the in vitro hydrolysates of salmon proteins of 11 selected peptides. In both types of salmon hydrolysates, ACE-inhibitory peptides IW, IY, TVY and VW were identified. In the in vitro salmon protein hydrolysates an ACE-inhibitory peptides VPW and VY were also detected, while ACE-inhibitory peptides ALPHA, IVY and IWHHT were identified in the hydrolysates generated with ex vivo digestion. In our studies, we documented ACE inhibitory in vitro effects of salmon protein hydrolysates obtained by human and as well as porcine gastrointestinal enzymes.

  17. Inhibition of Angiotensin Converting Enzyme, Angiotensin II Receptor Blocking, and Blood Pressure Lowering Bioactivity across Plant Families.

    PubMed

    Patten, Glen S; Abeywardena, Mahinda Y; Bennett, Louise E

    2016-01-01

    Hypertension is a major risk factor for coronary heart disease, kidney disease, and stroke. Interest in medicinal or nutraceutical plant bioactives to reduce hypertension has increased dramatically. The main biological regulation of mammalian blood pressure is via the renin-angiotensin-aldosterone system. The key enzyme is angiotensin converting enzyme (ACE) that converts angiotensin I into the powerful vasoconstrictor, angiotensin II. Angiotensin II binds to its receptors (AT1) on smooth muscle cells of the arteriole vasculature causing vasoconstriction and elevation of blood pressure. This review focuses on the in vitro and in vivo reports of plant-derived extracts that inhibit ACE activity, block angiotensin II receptor binding and demonstrate hypotensive activity in animal or human studies. We describe 74 families of plants that exhibited significant ACE inhibitory activity and 16 plant families with potential AT1 receptor blocking activity, according to in vitro studies. From 43 plant families including some of those with in vitro bioactivity, the extracts from 73 plant species lowered blood pressure in various normotensive or hypertensive in vivo models by the oral route. Of these, 19 species from 15 families lowered human BP when administered orally. Some of the active plant extracts, isolated bioactives and BP-lowering mechanisms are discussed.

  18. Electrochemically reduced graphene and iridium oxide nanoparticles for inhibition-based angiotensin-converting enzyme inhibitor detection.

    PubMed

    Kurbanoglu, Sevinc; Rivas, Lourdes; Ozkan, Sibel A; Merkoçi, Arben

    2017-02-15

    In this work, a novel biosensor based on electrochemically reduced graphene oxide and iridium oxide nanoparticles for the detection of angiotensin-converting enzyme inhibitor drug, captopril, is presented. For the preparation of the biosensor, tyrosinase is immobilized onto screen printed electrode by using 1-Ethyl-3-(3-dimethylaminopropyl)-carbodiimide and N-Hydroxysuccinimide coupling reagents, in electrochemically reduced graphene oxide and iridium oxide nanoparticles matrix. Biosensor response is characterized towards catechol, in terms of graphene oxide concentration, number of cycles to reduce graphene oxide, volume of iridium oxide nanoparticles and tyrosinase solution. The designed biosensor is used to inhibit tyrosinase activity by Captopril, which is generally used to treat congestive heart failure. It is an angiotensin-converting enzyme inhibitor that operates via chelating copper at the active site of tyrosinase and thioquinone formation. The captopril detections using both inhibition ways are very sensitive with low limits of detection: 0.019µM and 0.008µM for chelating copper at the active site of tyrosinase and thioquinone formation, respectively. The proposed methods have been successfully applied in captopril determination in spiked human serum and pharmaceutical dosage forms with acceptable recovery values.

  19. Production of Angiotensin I Converting Enzyme Inhibitory (ACE-I) Peptides during Milk Fermentation and Their Role in Reducing Hypertension.

    PubMed

    Rai, Amit Kumar; Sanjukta, Samurailatpam; Jeyaram, Kumaraswamy

    2015-10-13

    Fermented milk is a potential source of various biologically active peptides with specific health benefits. Angiotensin converting enzyme inhibitory (ACE-I) peptides are one of the most studied bioactive peptides produced during milk fermentation. The presence of these peptides is reported in various fermented milk products such as yoghurt, cheese, sour milk, etc, which are also available as commercial products. Many of the ACE-I peptides formed during milk fermentation are resistant to gastrointestinal digestion and inhibit angiotensin converting enzyme (ACE) in the rennin angiotension system (RAS). There are various factors, which affect the formation ACE-I peptides and their ability to reach the target tissue in active form, which includes type of starters (lactic acid bacteria, yeast, etc), substrate composition (casein type, whey protein, etc), composition of ACE-I peptide, pre and post fermentation treatments, and its stability during gastrointestinal digestion. The antihypertensive effect of fermented milk products has also been proved by various in-vitro and in-vivo (animal and human trials) experiments. This article reviews the literature on fermented milk products as a source of ACE-I peptides and various factors affecting the production and activity of ACE-I peptides.

  20. Angiotensin-converting enzyme inhibitor (enalapril maleate) accelerates recovery of mouse skin from UVB-induced wrinkles

    SciTech Connect

    Matsuura-Hachiya, Yuko; Arai, Koji Y.; Ozeki, Rieko; Kikuta, Ayako; Nishiyama, Toshio

    2013-12-06

    Highlights: •Angiotensin converting enzyme (ACE) increases in UVB-irradiated skin. •Administration of an ACE inhibitor improved UVB-induced skin wrinkle. •ACE inhibitor improved UVB-induced epidermal hypertrophy. •ACE inhibitor improved transepidermal water loss in the UVB-irradiated skin. -- Abstract: Angiotensin-converting enzyme (ACE) activity and angiotensin II signaling regulate cell proliferation, differentiation, and tissue remodeling, as well as blood pressure, while in skin, angiotensin II signaling is involved in wound healing, inflammation, and pathological scar formation. Therefore, we hypothesized that angiotensin II is also involved in photoaging of skin. In this study, we examined the effect of enalapril maleate, an ACE inhibitor, on recovery of wrinkled skin of hairless mice exposed to long-term UVB irradiation. Immunohistochemical observation revealed that expression of ACE, angiotensin II, and angiotensin II type 1 (AT1) and type 2 (AT2) receptors in the skin was increased after UVB irradiation (3 times/week at increasing intensities for 8 weeks). Administration of enalapril maleate (5 times/week for 6 weeks, starting 1 week after 10-week irradiation) accelerated recovery from UVB-induced wrinkles, epidermal hyperplasia and epidermal barrier dysfunction, as compared with the vehicle control. Our results indicate that ACE and angiotensin II activity are involved in skin photoaging, and suggest that ACE inhibitor such as enalapril maleate may have potential for improvement of photoaged skin.

  1. Angiotensin-I Converting Enzyme (ACE) Inhibitory and Anti-Oxidant Activities of Sea Cucumber (Actinopyga lecanora) Hydrolysates

    PubMed Central

    Ghanbari, Raheleh; Zarei, Mohammad; Ebrahimpour, Afshin; Abdul-Hamid, Azizah; Ismail, Amin; Saari, Nazamid

    2015-01-01

    In recent years, food protein-derived hydrolysates have received considerable attention because of their numerous health benefits. Amongst the hydrolysates, those with anti-hypertensive and anti-oxidative activities are receiving special attention as both activities can play significant roles in preventing cardiovascular diseases. The present study investigated the angiotensin-I converting enzyme (ACE) inhibitory and anti-oxidative activities of Actinopyga lecanora (A. lecanora) hydrolysates, which had been prepared by alcalase, papain, bromelain, flavourzyme, pepsin, and trypsin under their optimum conditions. The alcalase hydrolysate showed the highest ACE inhibitory activity (69.8%) after 8 h of hydrolysis while the highest anti-oxidative activities measured by 2,2-diphenyl 1-1-picrylhydrazyl radical scavenging (DPPH) (56.00%) and ferrous ion-chelating (FIC) (59.00%) methods were exhibited after 24 h and 8 h of hydrolysis, respectively. The ACE-inhibitory and anti-oxidative activities displayed dose-dependent trends, and increased with increasing protein hydrolysate concentrations. Moreover, strong positive correlations between angiotensin-I converting enzyme (ACE) inhibitory and anti-oxidative activities were also observed. This study indicates that A. lecanora hydrolysate can be exploited as a source of functional food owing to its anti-oxidant as well as anti-hypertension functions. PMID:26690117

  2. Involvement of Renin-Angiotensin System in Damage of Angiotensin-Converting Enzyme Inhibitor Captopril on Bone of Normal Mice.

    PubMed

    Liu, Jin-Xin; Wang, Liang; Zhang, Yan

    2015-01-01

    This study was performed to investigate the effect of angiotensin-converting enzyme inhibitor, captopril, on bone metabolism and histology, and the action of captopril on the components of the skeletal renin-angiotensin system (RAS) and bradykinin receptor in normal male mice. The mice were orally administered captopril (10 mg/kg) for 4 weeks with vehicle-treated mice as normal control. The histology of trabecular bone at the distal femoral end was determined by hematoxylin & eosin, Safranin O and Masson-Trichrome staining. The captopril-treated mice showed a decreased level of testosterone (p<0.05) and procollagen type I N-terminal propeptide (p<0.05) in serum as compared to those in the control group. Captopril has detrimental effects on trabecular bone as demonstrated by the loss of cancellous bone mass and network connections as well as changes to the chondrocytes zone. The expression of angiotensin-converting enzyme (p<0.05), renin receptor (p<0.01), angiotensin II (p<0.05) and bradykinin receptor 2 (p<0.05) was significantly up-regulated following the captopril treatment. Thus, the potential underlying mechanism of the damage of captopril on bone can be attributed the increased activity of local bone RAS and the activation of bradykinin receptor.

  3. Influence of angiotensin converting enzyme inhibition on pump function and cardiac contractility in patients with chronic congestive heart failure.

    PubMed Central

    Baur, L H; Schipperheyn, J J; Baan, J; van der Laarse, A; Buis, B; van der Wall, E E; Manger Cats, V; van Dijk, A D; Blokland, J A; Frölich, M

    1991-01-01

    Eleven patients with coronary artery disease and chronic heart failure were studied before and three months after the angiotensin converting enzyme inhibitor enalapril was added to their frusemide medication. The following were measured: left ventricular pressure and volume with transient occlusion of the inferior vena cava, radionuclide angiography, and hormone concentrations in plasma. As in other reported studies, the clinical condition of the patients improved and their exercise tolerance increased moderately. Addition of enalapril reduced end diastolic and systolic pressure, reduced ventricular volume, and concomitantly increased the ejection fraction. The end systolic pressure-volume relation shifted to the left as it did in a similar animal study. In the animal study unloading by a vasodilator did not induce a leftward shift, so it can be inferred that in the present study unloading combined with a decrease in the angiotensin concentration was instrumental in remodelling the heart. Though unloading was expected to have a beneficial effect on the oxygen supply/demand ratio of the heart, the patients still showed the same drop in the ejection fraction during exercise as they did before treatment with enalapril, and early diastolic filling did not improve. Normally, regression of cardiac dilatation is only found if pump function improves; the present study showed that unloading in combination with angiotensin converting enzyme inhibition reshapes the ventricle without improving intrinsic pump function. PMID:2015121

  4. Major amyloid-β-degrading enzymes, endothelin-converting enzyme-2 and neprilysin, are expressed by distinct populations of GABAergic interneurons in hippocampus and neocortex.

    PubMed

    Pacheco-Quinto, Javier; Eckman, Christopher B; Eckman, Elizabeth A

    2016-12-01

    Impaired clearance of amyloid-β peptide (Aβ) has been postulated to significantly contribute to the amyloid accumulation typical of Alzheimer's disease. Among the enzymes known to degrade Aβ in vivo are endothelin-converting enzyme (ECE)-1, ECE-2, and neprilysin (NEP), and evidence suggests that they regulate independent pools of Aβ that may be functionally significant. To better understand the differential regulation of Aβ concentration by its physiological degrading enzymes, we characterized the cell and region-specific expression pattern of ECE-1, ECE-2, and NEP by in situ hybridization and immunohistochemistry in brain areas relevant to Alzheimer's disease. In contrast to the broader distribution of ECE-1, ECE-2 and NEP were found enriched in GABAergic neurons. ECE-2 was majorly expressed by somatostatin-expressing interneurons and was active in isolated synaptosomes. NEP messenger RNA was found mainly in parvalbumin-expressing interneurons, with NEP protein localized to perisomatic parvalbuminergic synapses. The identification of somatostatinergic and parvalbuminergic synapses as hubs for Aβ degradation is consistent with the possibility that Aβ may have a physiological function related to the regulation of inhibitory signaling.

  5. Expression of interleukin 1β and interleukin 1β converting enzyme by intestinal macrophages in health and inflammatory bowel disease

    PubMed Central

    McAlindon, M; Hawkey, C; Mahida, Y

    1998-01-01

    Background—In the lipopolysaccharide (LPS) stimulated peripheral blood monocyte, the precursor form of interleukin 1β (IL-1β, 31 kD) is processed by IL-1β converting enzyme (ICE) to the mature, bioactive form (17 kD). IL-1β is a proinflammatory cytokine which is likely to have a role in the pathogenesis of inflammatory bowel disease (IBD). 
Aims—To investigate the expression and processing of IL-1β and ICE by tissue macrophages from normal and IBD colonic mucosa. 
Methods—Mucosal biopsy specimens and lamina propria cells from normal and IBD colons were studied by reverse transcription polymerase chain reaction (RT-PCR), western blot analysis, and ELISA (enzyme linked immunosorbent assay). 
Results—Normal colonic macrophages synthesised only the precursor form of IL-1β whereas in IBD the mature form was also produced. Similarly, cells from normal colonic mucosa synthesised ICE as the precursor (p45) only, whereas macrophages from IBD colons produced active (p20) ICE. Ac-Tyr-Val-Ala-Asp-CHO, a specific peptide aldehyde inhibitor of ICE, significantly reduced the amount of mature IL-1β released by isolated IBD macrophages (from a median of 1.2 (range 0.78-4.42) ng/ml to 0.43 (0.21-1.6) ng/ml; p<0.01). 
Conclusions—Exposure of normal colonic macrophages to LPS only induces the production of the precursor form of IL-1β, because the cells fail to activate ICE. In contrast, IBD colonic macrophages are able to activate ICE and hence release mature IL-1β in a manner similar to circulating monocytes. This is consistent with IBD macrophages being recently recruited from the circulating monocyte population. Targeted inhibition of ICE may represent a novel form of therapy in IBD. 

 Keywords: interleukin 1β; interleukin 1β converting enzyme; macrophages; lipopolysaccharide; ulcerative colitis; Crohn's disease PMID:9536946

  6. Inhibition of angiotensin I converting enzyme by subtilisin NAT (nattokinase) in natto, a Japanese traditional fermented food.

    PubMed

    Murakami, Keiko; Yamanaka, Naoki; Ohnishi, Katsunori; Fukayama, Minoru; Yoshino, Masataka

    2012-06-01

    Angiotensin I converting enzyme (ACE) was inhibited by the culture medium of Bacillus subtilis subsp. natto, which ferments boiled soy beans to natto, a Japanese traditional food. Subtilisin NAT (nattokinase) produced by B. subtilis also inhibited ACE, and the inhibition was markedly stimulated by heat treatment of subtilisin at 120 °C for 15 min. Inhibition of ACE by subtilisin was of a mixed type: the decrease in V(max) and the increase in K(m) value. SDS-polyacrylamide gel electrophoresis showed that heat treatment of subtilisin caused inactivation with fragmentation of the enzyme protein into small peptides. The inhibitory action of subtilisin was not due to an enzymatic action of protease, but may be ascribed to the potent ACE-inhibitory peptides such as LY and FY, amino acid sequences in subtilisin. HPLC-MS analysis of heat-inactivated subtilisin confirmed that LY and FY were liberated by fragmentation of the enzyme. Inhibition of ACE by subtilisin and its degradation peptides such as LY and FY may participate in the suppression of blood pressure by ingestion of natto.

  7. Angiotensin-converting enzyme gene polymorphism, left ventricular remodeling, and exercise capacity in strength-trained athletes.

    PubMed

    Kasikcioglu, Erdem; Kayserilioglu, Abidin; Ciloglu, Figen; Akhan, Hulya; Oflaz, Huseyin; Yildiz, Safinaz; Peker, Ismail

    2004-11-01

    The mechanisms that regulate the development of human physiological cardiac hypertrophy remain poorly understood. The renin-angiotensin system, which is modulated by genetic polymorphism, plays an important role in the regulation of vascular tone and myocardial hypertrophy. Although a few studies have analyzed the association of angiotensin-converting enzyme (ACE) polymorphism and left ventricular (LV) hypertrophy in isotonic exercise-trained subjects who developed eccentric cardiac hypertrophy, there has been no research done in power athletes who developed concentric cardiac hypertrophy. We have hypothesized that ACE genotypic modulation characteristics may affect LV mass in power athletes. This study included 29 elite Caucasian wrestlers (mean age, 22.6 years) and 51 age-matched sedentary subjects. According to the absence or presence of the insertion segment in the polymerase chain reaction (PCR) product, the subjects were classified as homozygous deletion-deletion (DD), insertion-insertion (II), or heterozygous insertion-deletion (ID). The association of LV hypertrophy with ACE gene insertion/deletion (I/D) polymorphism was analyzed. Left ventricular mass and index were determined by echocardiography. Angiotensin-converting enzyme genotyping was performed on peripheral leukocytes using the polymerase chain reaction technique. The study and control group subjects were similar in height and weight. Left ventricular hypertrophy in the athletes was more apparent than in the controls. Angiotensin-converting enzyme genotype II frequency was 17.2% (5) in the athletes, 17.6% (9) in the controls; ID frequency was 51.7% (15) in the athletes, 56.8% (29) in the controls; and the DD frequency was 31% (9) in the athletes and 25.4% (13) in the controls. Left ventricular mass and mass index were found to be higher in genotype DD (126.2 +/- 2.9g/m2) than genotype II (85.5 +/- 4.0g/m2) or genotype ID (110.1 +/- 2.3g/m2) in the athletes (P < 0.001). Furthermore, maximal oxygen

  8. Transcription and activity of 5-fluorouracil converting enzymes in fluoropyrimidine resistance in colon cancer in vitro.

    PubMed

    Mader, R M; Sieder, A E; Braun, J; Rizovski, B; Kalipciyan, M; Mueller, M W; Jakesz, R; Rainer, H; Steger, G G

    1997-12-01

    Cellular resistance to 5-fluorouracil (5-FU) is not completely understood. Since 5-FU shares the pyrimidine pathway with the physiological pyrimidines, we investigated the relationship between fluoropyrimidine metabolism, nucleic acid uptake and cytotoxicity of 5-FU in eight colon tumour cell lines including 5-FU-resistant subclones. The cytotoxicity of 5-FU was increased up to 423-fold when the anabolites 5-fluorouridine (FUrd), 5-fluorodeoxyuridine (FdUrd), and 5-fluorodeoxyuridine monophosphate (FdUMP) were compared with the parent drug in vitro. The enzymes uridine phosphorylase and thymidine phosphorylase were predictive for the cytotoxicity of 5-FU in 5/7 cell lines. Inhibition of uridine phosphorylase and thymidine phosphorylase by antisense strategies effectively antagonised 5-FU, abolishing 84% and 79% of its toxicity. The importance of thymidine phosphorylase was supported by a highly restricted enzyme activity in 5-FU-resistant cells. In 5-FU naive cells, a stimulating effect of 5-FU on thymidylate synthase mRNA and ribonucleotide reductase mRNA expression was observed. In these cells, antisense oligonucleotides to ribonucleotide reductase significantly reduced cell growth. Downregulation of ribonucleotide reductase mRNA in 5-FU-resistant subclones suggests different mechanisms in primary and secondary resistance to 5-FU. Most of the intracellular 5-FU was selectively incorporated into RNA (range: 45-91%) and generally spared DNA (range: 0.2-11%). In synthesising our data, we conclude that drug resistance could be overwhelmed through bypassing limiting steps in the activation of 5-FU. In the majority of colonic tumours, the activity of uridine phosphorylase and thymidine phosphorylase may have prognostic relevance for the cytotoxicity of 5-FU in vitro.

  9. Angiotensin converting enzyme 2 gene expression increased compensatory for left ventricular remodeling in patients with end-stage heart failure.

    PubMed

    Ohtsuki, Masatsugu; Morimoto, Shin-ichiro; Izawa, Hideo; Ismail, Tevfik F; Ishibashi-Ueda, Hatsue; Kato, Yasuchika; Horii, Taiko; Isomura, Tadashi; Suma, Hisayoshi; Nomura, Masanori; Hishida, Hitoshi; Kurahashi, Hiroki; Ozaki, Yukio

    2010-11-19

    It has been reported that angiotensin converting enzyme (ACE) 2, a homologue of ACE, has direct effects on cardiac function. However, the role of ACE2 in the development of human heart failure is not fully understood. We evaluated the expression of the ACE2 gene by means of real-time RT-PCR in myocardium from 14 patients with end-stage heart failure. The amount of ACE2 mRNA positively correlated with left ventricular (LV) end-diastolic diameter (r(2)=0.56, p<0.01) but did not significantly correlate with LV ejection fraction or plasma brain natriuretic peptide levels. In conclusion, our data show that the up-regulation of the ACE2 gene in the LV myocardium of patients with severe heart failure was associated with the degree of LV dilatation and may thereby constitute an important adaptive mechanism to retard the progression of adverse LV remodeling.

  10. Media effects in modulating the conformational equilibrium of a model compound for tumor necrosis factor converting enzyme inhibition

    NASA Astrophysics Data System (ADS)

    Banchelli, Martina; Guardiani, Carlo; Sandberg, Robert B.; Menichetti, Stefano; Procacci, Piero; Caminati, Gabriella

    2015-07-01

    Small-molecule inhibitors of Tumor Necrosis Factor α Converting Enzyme (TACE) are a promising therapeutic tool for Rheumatoid Arthritis, Multiple Sclerosis and other autoimmune diseases. Here we report on an extensive chemical-physical analysis of the media effects in modulating the conformational landscape of MBET306, the common scaffold and a synthetic precursor of a family of recently discovered tartrate-based TACE inhibitors. The structural features of this molecule with potential pharmaceutical applications have been disclosed by interpreting extensive photophysical measurements in various solvents with the aid of enhanced sampling molecular dynamics simulations and time dependent density functional calculations. Using a combination of experimental and computational techniques, the paper provides a general protocol for studying the structure in solution of molecular systems characterized by the existence of conformational metastable states.

  11. Interaction of angiotensin-converting enzyme (ACE) with membrane-bound carboxypeptidase M (CPM) - a new function of ACE.

    PubMed

    Sun, Xiaoou; Wiesner, Burkhard; Lorenz, Dorothea; Papsdorf, Gisela; Pankow, Kristin; Wang, Po; Dietrich, Nils; Siems, Wolf-Eberhard; Maul, Björn

    2008-12-01

    Angiotensin-converting enzyme (ACE) demonstrates, besides its typical dipeptidyl-carboxypeptidase activity, several unusual functions. Here, we demonstrate with molecular, biochemical, and cellular techniques that the somatic wild-type murine ACE (mACE), stably transfected in Chinese Hamster Ovary (CHO) or Madin-Darby Canine Kidney (MDCK) cells, interacts with endogenous membranal co-localized carboxypeptidase M (CPM). CPM belongs to the group of glycosylphosphatidylinositol (GPI)-anchored proteins. Here we report that ACE, completely independent of its known dipeptidase activities, has GPI-targeted properties. Our results indicate that the spatial proximity between mACE and the endogenous CPM enables an ACE-evoked release of CPM. These results are discussed with respect to the recently proposed GPI-ase activity and function of sperm-bound ACE.

  12. Synthesis and biological studies of highly concentrated lisinopril-capped gold nanoparticles for CT tracking of angiotensin converting enzyme (ACE)

    NASA Astrophysics Data System (ADS)

    Ghann, William E.; Aras, Omer; Fleiter, Thorsten; Daniel, Marie-Christine

    2011-05-01

    For patients with a history of heart attack or stroke, the prevention of another cardiovascular or cerebrovascular event is crucial. The development of cardiac and pulmonary fibrosis has been associated with overexpression of tissue angiotensin-converting enzyme (ACE). Recently, gold nanoparticles (GNPs) have shown great potential as X-ray computed tomography (CT) contrast agents. Since lisinopril is an ACE inhibitor, it has been used as coating on GNPs for targeted imaging of tissue ACE in prevention of fibrosis. Herein, lisinopril-capped gold nanoparticles (LIS-GNPs) were synthesized up to a concentration of 55 mgAu/mL. Their contrast was measured using CT and the results were compared to Omnipaque, a commonly used iodine-based contrast agent. The targeting ability of these LIS-GNPs was also assessed.

  13. Effects of nabumetone, celecoxib, and ibuprofen on blood pressure control in hypertensive patients on angiotensin converting enzyme inhibitors.

    PubMed

    Palmer, Robert; Weiss, Robert; Zusman, Randall M; Haig, Ann; Flavin, Susan; MacDonald, Brian

    2003-02-01

    Nonsteroidal anti-inflammatory drugs interfere with certain antihypertensive therapies. In a double-blind study, 385 hypertensive patients stabilized on an angiotensin converting enzyme inhibitor were treated with nabumetone, celecoxib, ibuprofen, or placebo for 4 weeks. Ibuprofen caused significantly greater increases in systolic (P < .001) and diastolic (P < .01) blood pressures (BPs) compared to placebo, but not nabumetone or celecoxib. The proportion of patients with systolic BP increases of clinical concern at end point was significantly higher (P < .001) for the ibuprofen group (16.7%; 15 of 90), but not for the nabumetone group (5.5%; 5 of 91) or the celecoxib group (4.6%; 4 of 87) compared to the placebo group (1.1%; 1 of 91).

  14. Angiotensin converting enzyme inhibitors and angiotensin II receptor antagonist attenuate tumor growth via polarization of neutrophils toward an antitumor phenotype

    PubMed Central

    Shrestha, Sanjeeb; Noh, Jae Myoung; Kim, Shin-Yeong; Ham, Hwa-Yong; Kim, Yeon-Ja; Yun, Young-Jin; Kim, Min-Ju; Kwon, Min-Soo; Song, Dong-Keun; Hong, Chang-Won

    2016-01-01

    ABSTRACT Tumor microenvironments polarize neutrophils to protumoral phenotypes. Here, we demonstrate that the angiotensin converting enzyme inhibitors (ACEis) and angiotensin II type 1 receptor (AGTR1) antagonist attenuate tumor growth via polarization of neutrophils toward an antitumoral phenotype. The ACEis or AGTR1 antagonist enhanced hypersegmentation of human neutrophils and increased neutrophil cytotoxicity against tumor cells. This neutrophil hypersegmentation was dependent on the mTOR pathway. In a murine tumor model, ACEis and AGTR1 antagonist attenuated tumor growth and enhanced neutrophil hypersegmentation. ACEis inhibited tumor-induced polarization of neutrophils to a protumoral phenotype. Neutrophil depletion reduced the antitumor effect of ACEi. Together, these data suggest that the modulation of Ang II pathway attenuates tumor growth via polarization of neutrophils to an antitumoral phenotype. PMID:26942086

  15. Synthesis and evaluation of novel triazoles and mannich bases functionalized 1,4-dihydropyridine as angiotensin converting enzyme (ACE) inhibitors.

    PubMed

    Kumbhare, Ravindra M; Kosurkar, Umesh B; Bagul, Pankaj K; Kanwal, Abhinav; Appalanaidu, K; Dadmal, Tulshiram L; Banerjee, Sanjay Kumar

    2014-11-01

    A series of novel diethyl 2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate embedded triazole and mannich bases were synthesized, and evaluated for their angiotensin converting enzyme (ACE) inhibitory activity. Screening of above synthesized compounds for ACE inhibition showed that triazoles functionalized compounds have better ACE inhibitory activity compared to that of mannich bases analogues. Among all triazoles we found 6 h, 6 i and 6 j to have good ACE inhibition activity with IC50 values 0.713 μM, 0.409 μM and 0.653 μM, respectively. Among mannich bases series compounds, only 7c resulted as most active ACE inhibitor with IC50 value of 0.928 μM.

  16. Angiotensin-converting enzyme 2/angiotensin-(1–7)/Mas axis activates Akt signaling to ameliorate hepatic steatosis

    PubMed Central

    Cao, Xi; Yang, Fangyuan; Shi, Tingting; Yuan, Mingxia; Xin, Zhong; Xie, Rongrong; Li, Sen; Li, Hongbing; Yang, Jin-Kui

    2016-01-01

    The classical axis of renin-angiotensin system (RAS), angiotensin (Ang)-converting enzyme (ACE)/Ang II/AT1, contributes to the development of non-alcoholic fatty liver disease (NAFLD). However, the role of bypass axis of RAS (Angiotensin-converting enzyme 2 (ACE2)/Ang-(1–7)/Mas) in hepatic steatosis is still unclear. Here we showed that deletion of ACE2 aggravates liver steatosis, which is correlated with the increased expression of hepatic lipogenic genes and the decreased expression of fatty acid oxidation-related genes in the liver of ACE2 knockout (ACE2−/y) mice. Meanwhile, oxidative stress and inflammation were also aggravated in ACE2−/y mice. On the contrary, overexpression of ACE2 improved fatty liver in db/db mice, and the mRNA levels of fatty acid oxidation-related genes were up-regulated. In vitro, Ang-(1–7)/ACE2 ameliorated hepatic steatosis, oxidative stress and inflammation in free fatty acid (FFA)-induced HepG2 cells, and what’s more, Akt inhibitors reduced ACE2-mediated lipid metabolism. Furthermore, ACE2-mediated Akt activation could be attenuated by blockade of ATP/P2 receptor/Calmodulin (CaM) pathway. These results indicated that Ang-(1–7)/ACE2/Mas axis may reduce liver lipid accumulation partly by regulating lipid-metabolizing genes through ATP/P2 receptor/CaM signaling pathway. Our findings support the potential role of ACE2/Ang-(1–7)/Mas axis in prevention and treatment of hepatic lipid metabolism. PMID:26883384

  17. Perioperative management of patients treated with angiotensin-converting enzyme inhibitors and angiotensin II receptor blockers: a quality improvement audit.

    PubMed

    Vijay, A; Grover, A; Coulson, T G; Myles, P S

    2016-05-01

    Previous studies have shown that patients continuing angiotensin-converting enzyme inhibitors or angiotensin II receptor blockers on the day of surgery are more likely to have significant intraoperative hypotension, higher rates of postoperative acute kidney injury, and lower incidences of postoperative atrial fibrillation. However, many of these studies were prone to bias and confounding, and questions remain over the validity of these outcomes. This observational, before-and-after quality improvement audit aimed to assess the effect of withholding these medications on the morning of surgery. We recruited 323 participants, with 83 (26%) having their preoperative angiotensin-converting enzyme inhibitor (ACEi) or angiotensin II receptor blocker (ARB) withheld on the day of surgery. There were only very small Spearman rank-order correlations between time since last dose of these medications (rho -0.12, P=0.057) and intraoperative and recovery room intravenous fluid administration (rho -0.11, P=0.042). There was no statistically significant difference between the continued or withheld groups in vasopressor (metaraminol use 3.5 [1.5-8.3] mg versus 3.5 [1.5-8.5] mg, P=0.67) or intravenous fluid administration (1000 ml [800-1500] ml versus 1000 [800-1500] ml, P=0.096), nor rates of postoperative acute kidney injury (13% vs 18%, P=0.25) or atrial fibrillation (15% versus 18%, P=0.71). This audit found no significant differences in measured outcomes between the continued or withheld ACEi/ARB groups. This finding should be interpreted with caution due to the possibility of confounding and an insufficient sample size. However, as the finding is in contrast to many previous studies, future prospective randomised clinical trials are required to answer this important question.

  18. The toxicity of angiotensin converting enzyme inhibitors to larvae of the disease vectors Aedes aegypti and Anopheles gambiae

    PubMed Central

    Abu Hasan, Zatul-’Iffah; Williams, Helen; Ismail, Nur M.; Othman, Hidayatulfathi; Cozier, Gyles E.; Acharya, K. Ravi; Isaac, R. Elwyn

    2017-01-01

    The control of mosquitoes is threatened by the appearance of insecticide resistance and therefore new control chemicals are urgently required. Here we show that inhibitors of mosquito peptidyl dipeptidase, a peptidase related to mammalian angiotensin-converting enzyme (ACE), are insecticidal to larvae of the mosquitoes, Aedes aegypti and Anopheles gambiae. ACE inhibitors (captopril, fosinopril and fosinoprilat) and two peptides (trypsin-modulating oostatic factor/TMOF and a bradykinin-potentiating peptide, BPP-12b) were all inhibitors of the larval ACE activity of both mosquitoes. Two inhibitors, captopril and fosinopril (a pro-drug ester of fosinoprilat), were tested for larvicidal activity. Within 24 h captopril had killed >90% of the early instars of both species with 3rd instars showing greater resistance. Mortality was also high within 24 h of exposure of 1st, 2nd and 3rd instars of An. gambiae to fosinopril. Fosinopril was also toxic to Ae. aegypti larvae, although the 1st instars appeared to be less susceptible to this pro-drug even after 72 h exposure. Homology models of the larval An. gambiae ACE proteins (AnoACE2 and AnoACE3) reveal structural differences compared to human ACE, suggesting that structure-based drug design offers a fruitful approach to the development of selective inhibitors of mosquito ACE enzymes as novel larvicides. PMID:28345667

  19. The toxicity of angiotensin converting enzyme inhibitors to larvae of the disease vectors Aedes aegypti and Anopheles gambiae.

    PubMed

    Abu Hasan, Zatul-'Iffah; Williams, Helen; Ismail, Nur M; Othman, Hidayatulfathi; Cozier, Gyles E; Acharya, K Ravi; Isaac, R Elwyn

    2017-03-27

    The control of mosquitoes is threatened by the appearance of insecticide resistance and therefore new control chemicals are urgently required. Here we show that inhibitors of mosquito peptidyl dipeptidase, a peptidase related to mammalian angiotensin-converting enzyme (ACE), are insecticidal to larvae of the mosquitoes, Aedes aegypti and Anopheles gambiae. ACE inhibitors (captopril, fosinopril and fosinoprilat) and two peptides (trypsin-modulating oostatic factor/TMOF and a bradykinin-potentiating peptide, BPP-12b) were all inhibitors of the larval ACE activity of both mosquitoes. Two inhibitors, captopril and fosinopril (a pro-drug ester of fosinoprilat), were tested for larvicidal activity. Within 24 h captopril had killed >90% of the early instars of both species with 3(rd) instars showing greater resistance. Mortality was also high within 24 h of exposure of 1(st), 2(nd) and 3(rd) instars of An. gambiae to fosinopril. Fosinopril was also toxic to Ae. aegypti larvae, although the 1(st) instars appeared to be less susceptible to this pro-drug even after 72 h exposure. Homology models of the larval An. gambiae ACE proteins (AnoACE2 and AnoACE3) reveal structural differences compared to human ACE, suggesting that structure-based drug design offers a fruitful approach to the development of selective inhibitors of mosquito ACE enzymes as novel larvicides.

  20. Monoclonal Antibody against Angiotensin-Converting Enzyme: Its Use as a Marker for Murine, Bovine, and Human Endothelial Cells

    NASA Astrophysics Data System (ADS)

    Auerbach, R.; Alby, L.; Grieves, J.; Joseph, J.; Lindgren, C.; Morrissey, L. W.; Sidky, Y. A.; Tu, M.; Watt, S. L.

    1982-12-01

    A monoclonal antibody has been prepared against rat angiotensin-converting enzyme (ACE). By selection for antibody binding to endothelial cells of bovine rather than rat origin we have obtained a reagent that has broad cross-species binding properties and that can at the same time serve as a useful marker for the surface of endothelial cells. The IgM-producing clone that we have established, α -ACE 3.1.1, has been grown in ascites form to yield ascites fluid that binds selectively to immobilized ACE at a >1:10,000 dilution. By use of enzyme-linked immunosorbent assays, immunofluorescence histology, and flow cytometry, we have demonstrated the presence of ACE on endothelial cells of murine, bovine, and human origin. By means of a fluorescence-activated cell sorter (FACS-IV) we have been able to selectively isolate viable endothelial cells from a mixture of endothelial cells and fibroblasts. We believe the antibody will be useful not only for the selection and in vitro cultivation of endothelial cells but also as a tool for the identification and pharmacological study of ACE.

  1. Bioactive peptides from Atlantic salmon (Salmo salar) with angiotensin converting enzyme and dipeptidyl peptidase IV inhibitory, and antioxidant activities.

    PubMed

    Neves, Adriana C; Harnedy, Pádraigín A; O'Keeffe, Martina B; FitzGerald, Richard J

    2017-03-01

    The pH shift method was utilised for the recovery of proteins from salmon trimmings (ST), yielding 93% (w/w) protein. ST protein (STP) hydrolysates were generated with different enzyme preparations. STP incubated with Corolase PP for 1h (STP-C1) had the most potent angiotensin converting enzyme (ACE) and dipeptidyl peptidase IV (DPP-IV) inhibitory and oxygen radical absorbance capacity (ORAC) activities. Analysis of fractions of STP-C1 using UPLC-MS/MS identified sixteen peptides/amino acids. Tyr-Pro had the highest ACE inhibitory activity (ACE IC50=5.21±0.94μM). The highest DPP-IV inhibitory activity was found with the amino acid Tyr (DPP-IV IC50=75.15±0.84μM). Val-Pro had the highest ORAC activity (19.45±2.15μmol of TEg(-1)). To our knowledge, the peptides Gly-Pro-Ala-Val, Val-Cys, and Phe-Phe have not been previously identified to have the activities tested in this study. These results indicate that STP hydrolysates are potential sources of bioactive peptides.

  2. Compartmentalization and cyclic variation of immunoreactivity of renin and angiotensin converting enzyme in human endometrium throughout the menstrual cycle.

    PubMed

    Li, X F; Ahmed, A

    1997-12-01

    Renin and angiotensin converting enzymes (ACE) are responsible for the generation of angiotensin II which regulates blood pressure and fluid/electrolyte homeostasis. The cellular localization and cyclic distribution of renin and ACE in human endometrium are demonstrated in this study. Immunohistochemical studies revealed that both renin and ACE were consistently localized in the endometrial glandular epithelia throughout the menstrual cycle; however, the immunostainings respectively for ACE and renin were weak and moderate in stromal cells of proliferative endometrium and negligible in secretory endometrium. No renin immunostaining was detected around endometrial blood vessels. Although endothelial cells consistently stained for ACE, no renin immunoreactivity was detected in these cells during the menstrual cycle. Western blot analysis using ACE antibody directed against human kidney identified a single protein band with a relative molecular mass of approximately 153 kDa. The intensity of this band showed cyclic variation during the menstrual cycle with the highest ACE expression during the late secretory phase and at menses suggesting that ACE plays a role in the initiation of menstruation. The differences in the cellular distribution patterns of these two enzymes further supports our previous proposition that angiotensin II has different functions at the different stages of the menstrual cycle.

  3. Production of feather hydrolysates with antioxidant, angiotensin-I converting enzyme- and dipeptidyl peptidase-IV-inhibitory activities.

    PubMed

    Fontoura, Roberta; Daroit, Daniel J; Correa, Ana P F; Meira, Stela M M; Mosquera, Mauricio; Brandelli, Adriano

    2014-09-25

    The antioxidant and antihypertensive activities of feather hydrolysates obtained with the bacterium Chryseobacterium sp. kr6 were investigated. Keratin hydrolysates were produced with different concentrations of thermally denatured feathers (10-75 g l(-1)) and initial pH values (6.0-9.0). Soluble proteins accumulated in high amounts in media with 50 and 75 g l(-1) of feathers, reaching values of 18.5 and 22 mg ml(-1), respectively, after 48 hours of cultivation. In media with 50 g l(-1) of feathers, initial pH had minimal effect after 48 hours. Maximal protease production was observed after 24 hours of cultivation, and feather concentration and initial pH values showed no significant effect on enzyme yields at this time. Feather hydrolysates displayed in vitro antioxidant properties, and optimal antioxidant activities were observed in cultures with 50 g l(-1) feathers, at initial pH 8.0, after 48 hours growth at 30°C. Also, feather hydrolysates were demonstrated to inhibit the angiotesin I-converting enzyme by 65% and dipeptidyl peptidase-IV by 44%. The bioconversion of an abundant agroindustrial waste such as chicken feathers can be utilized as a strategy to obtain hydrolysates with antioxidant and antihypertensive activities. Feather hydrolysates might be employed as supplements in animal feed, and also as a potential source of bioactive molecules for feed, food and drug development.

  4. Mixed inhibitors of angiotensin-converting enzyme and enkephalinase: Rational design, properties, and potential cardiovascular applications of glycopril and alatriopril

    SciTech Connect

    Gros, C.; Noel, N.; Souque, A.; Schwartz, J.C. ); Danvy, D.; Plaquevent, J.C.; Duhamel, L.; Duhamel, P. ); Lecomte, J.M. ); Bralet, J. )

    1991-05-15

    Angiotensin-converting enzyme (ACE) and enkephalinase, two cell surface metallopeptidases, are responsible for angiotensin II formation and atrial natriuretic factor (ANF) degradation, respectively, and thereby play a critical role in the metabolism of hormonal peptides exerting essentially opposite actions in cardiovascular regulations. To affect simultaneously both hormonal systems by a single molecular structure, the authors designed glycoprilat and alatrioprilat {l brace}(S)-N-(3-(3,4-methylenedioxyphenyl)-2-(mercaptomethyl)-1-oxopropyl)glycine and -alanine, respectively{r brace}. In vitro the two compounds inhibit both ACE and enkephalinase activities with similar, nanomolar potencies, and in vivo, glycopril and alatriopril, the corresponding diester prodrugs, occupy the two enzyme molecules in lung at similar low dosages. The high potency of these compounds is attributable to interaction of the methylenedioxy group with the S{sub 1} subsite of ACE and of the aromatic ring with the S{prime}{sub 1} subsite of enkephalinase. In rodents, low doses of these mixed inhibitors exert typical actions of ACE inhibitors--i.e., prevention of angiotensin I-induced hypertension-as well as of enkephalinase inhibitors--i.e., protection from {sup 125}I-ANF degradation or enhancement of diuresis and natriuresis following acute extracellular volume expansion. In view of the known counterbalanced physiological actions of the two hormonal peptides, whose metabolism is controlled by ACE and enkephalinase, mixed inhibitors of the two peptidases show promise for the treatment of various cardiovascular and salt-retention disorders.

  5. Insights into the Hypertensive Effects of Tityus serrulatus Scorpion Venom: Purification of an Angiotensin-Converting Enzyme-Like Peptidase

    PubMed Central

    Cajado-Carvalho, Daniela; Kuniyoshi, Alexandre Kazuo; Duzzi, Bruno; Iwai, Leo Kei; de Oliveira, Úrsula Castro; Junqueira de Azevedo, Inácio de Loiola Meirelles; Kodama, Roberto Tadashi; Portaro, Fernanda Vieira

    2016-01-01

    The number of cases of envenomation by scorpions has grown significantly in Brazil since 2007, with the most severe cases being caused by the Tityus serrulatus scorpion. Although envenomed patients mostly suffer neurotoxic manifestations, other symptoms, such as hypertension, cannot be exclusively attributed to neurotoxins. Omics analyses have detected plentiful amounts of metalloproteases in T. serrulatus venom. However, the roles played by these enzymes in envenomation are still unclear. Endeavoring to investigate the functions of scorpion venom proteases, we describe here for the first time an Angiotensin I-Converting Enzyme-like peptidase (ACE-like) purified from T. serrulatus venom. The crude venom cleaved natural and fluorescent substrates and these activities were inhibited by captopril. Regarding the serum neutralization, the scorpion antivenom was more effective at blocking the ACE-like activity than arachnid antivenom, although neither completely inhibited the venom cleavage action, even at higher doses. ACE-like was purified from the venom after three chromatographic steps and its identity was confirmed by mass spectrometric and transcriptomic analyses. Bioinformatics analysis showed homology between the ACE-like transcript sequences from Tityus spp. and human testis ACE. These findings advance our understanding of T. serrulatus venom components and may improve treatment of envenomation victims, as ACE-like may contribute to envenomation symptoms, especially the resulting hypertension. PMID:27886129

  6. Is there a place for combining angiotensin-converting enzyme inhibitors and angiotensin-receptor antagonists in the treatment of hypertension, renal disease or congestive heart failure?

    PubMed

    Taylor, A A

    2001-09-01

    Angiotensin-converting enzyme inhibitors and angiotensin II receptor subtype 1 antagonists have proven to be effective and well tolerated antihypertensive agents. They also exhibit unique cardioprotective and renoprotective properties in patients with comorbid conditions such as congestive heart failure and proteinuria or renal insufficiency. This benefit is observed most dramatically in diabetic persons. Although inconclusive, the results of a limited number of clinical trials support the notion that additive antihypertensive, cardioprotective, and renoprotective effects may be obtained with combined used of angiotensin-converting enzyme inhibitors and angiotensin II receptor subtype 1 antagonists in some patients. More studies are needed to confirm the findings of these preliminary studies, and to define more clearly those subsets of patients who might derive the greatest benefit from angiotensin-converting enzyme inhibitor-angiotensin II receptor subtype 1 antagonist combination therapy.

  7. Induction by Glucocorticoids of Angiotensin Converting Enzyme Production from Bovine Endothelial Cells in Culture and Rat Lung In Vivo

    PubMed Central

    Mendelsohn, F. A. O.; Lloyd, C. J.; Kachel, C.; Funder, J. W.

    1982-01-01

    The effect of corticosteroids on angiotensin converting enzyme was investigated in endothelial cell cultures and intact rat lung. Cultured endothelial cells from bovine aorta showed net production of angiotensin converting enzyme (ACE) over 2 d culture in serum-free medium. Dexamethasone (DM) increased cell ACE activity six- to sevenfold at 100 nM with a threshold effect at 0.3 nM. The effect of DM on ACE production was completely inhibited by actinomycin D or cycloheximide. Deoxycorticosterone (DOC) and aldosterone were markedly less active, with a threshold near 100 nM and significant (two to threefold) stimulation of ACE activity at 1 μM. In cells incubated in the presence of 10 nM DM, DOC (10 μM) significantly inhibited ACE production compared with 10 nM DM alone, suggesting that DOC is a partial agonist/partial antagonist in this enzyme system. Protein content of cells or medium was unchanged by steroids at all doses used. In vivo, adrenalectomized rats showed lower pulmonary ACE compared with intact controls, and when injected with DM (40 μg/d for 4 d) showed a significant (twofold, P < 0.002) increase in lung ACE over oil-injected, adrenalectomized controls; serum ACE did not change. Injection with DOC (40 μg/d) or aldosterone (10 μg/d) had no effect on lung or serum ACE. Over a range (0.6 to 2,000 μg) of concentrations of DM administered daily for 7 d, the dose-response curve of DM for induction of pulmonary ACE mirrored that for thymolysis; for both, half-maximal effects were seen at ∼6 μg DM/d, and plateau levels at 60 μg/d. We conclude that glucocorticoids are potent inducers of ACE activity in endothelial cells in culture and in rat lung in vivo, and that the action of aldosterone and DOC reflects occupancy of glucocorticoid receptors. This effect may be of (patho)physiological relevance in regulating levels of ACE in local vascular beds, and thereby modulating local levels of the vasoactive peptides angiotensin II and bradykinin. PMID:6286730

  8. The endopeptidase activity and the activation by Cl- of angiotensin-converting enzyme is evolutionarily conserved: purification and properties of an an angiotensin-converting enzyme from the housefly, Musca domestica.

    PubMed Central

    Lamango, N S; Sajid, M; Isaac, R E

    1996-01-01

    A soluble 67 kDa angiotensin-converting enzyme (ACE) has been purified by lisinopril-Sepharose affinity column chromatography from adult houseflies, Musca domestica. The dipeptidyl carboxypeptidase activity towards benzoyl-Gly-His-Leu was inhibited by captopril (IC50 50 nM) and fosinoprilat (IC50 251 nM), two inhibitors of mammalian ACE, and was activated by Cl- (optimal Cl- concentration 600 mM). Musca ACE removed C-terminal dipeptides from angiotensin I, bradykinin [Leu5]enkephalin and [Met5]enkephalin and also functioned as an endopeptidase by hydrolysing dipeptideamides from [Leu5]enkephalinamide and [Met5]enkephalinamide, and a dipeptideamide and a tripeptideamide from substance P. Musca ACE was also able to cleave a tripeptide from both the N-terminus and C-terminus of luteinizing hormone-releasing hormone, with C-terminal hydrolysis predominating. Maximal N-terminal tripeptidase activity occurred at 150 mM NaCl, whereas the C-terminal tripeptidase activity continued to rise with increasing concentration of Cl- (0-0.5 M). Musca ACE displays properties of both the N- and C-domains of human ACE, indicating a high degree of conservation during evolution of the substrate specificity of ACE and its response to Cl-. PMID:8670080

  9. Angioedema Related to Angiotensin-Converting Enzyme Inhibitors: Attack Severity, Treatment, and Hospital Admission in a Prospective Multicenter Study.

    PubMed

    Javaud, Nicolas; Achamlal, Jallal; Reuter, Paul-George; Lapostolle, Frédéric; Lekouara, Akim; Youssef, Mustapha; Hamza, Lilia; Karami, Ahmed; Adnet, Frédéric; Fain, Olivier

    2015-11-01

    The number of cases of acquired angioedema related to angiotensin converting enzyme inhibitors induced (ACEI-AAE) is on the increase, with a potential concomitant increase in life-threatening attacks of laryngeal edema. Our objective was to determine the main characteristics of ACEI-AAE attacks and, in doing so, the factors associated with likelihood of hospital admission from the emergency department (ED) after a visit for an attack.A prospective, multicenter, observational study (April 2012-December 2014) was conducted in EDs of 4 French hospitals in collaboration with emergency services (SAMU 93) and a reference center for bradykinin-mediated angioedema. For each patient presenting with an attack, emergency physicians collected demographic and clinical presentation data, treatments, and clinical course. They recorded time intervals from symptom onset to ED arrival and to treatment decision, from ED arrival to specific treatment with plasma-derived C1-inhibitor (C1-INH) or icatibant, and from specific treatment to onset of symptom relief. Attacks requiring hospital admission were compared with those not requiring admission.Sixty-two eligible patients with ACEI-AAE (56% men, median age 63 years) were included. Symptom relief occurred significantly earlier in patients receiving specific treatment than in untreated patients (0.5 [0.5-1.0] versus 3.9 [2.5-7.0] hours; P < 0.0001). Even though icatibant was injected more promptly than plasma-derived C1-INH, there, however, was no significant difference in median time to onset of symptom relief between the 2 drugs (0.5 [0.5-1.3] versus 0.5 [0.4-1.0] hours for C1-INH and icatibant, respectively, P = 0.49). Of the 62 patients, 27 (44%) were admitted to hospital from the ED. In multivariate analysis, laryngeal involvement and progressive swelling at ED arrival were independently associated with admission (Odds ratio [95% confidence interval] = 6.2 [1.3-28.2] and 5.9 [1.3-26.5], respectively). A favorable course

  10. Cell Signaling, Internalization, and Nuclear Localization of the Angiotensin Converting Enzyme in Smooth Muscle and Endothelial Cells*

    PubMed Central

    Lucero, Héctor A.; Kintsurashvili, Ekaterina; Marketou, Maria E.; Gavras, Haralambos

    2010-01-01

    The angiotensin converting enzyme (ACE) catalyzes the extracellular formation of angiotensin II, and degradation of bradykinin, thus regulating blood pressure and renal handling of electrolytes. We have previously shown that exogenously added ACE elicited transcriptional regulation independent of its enzymatic activity. Because transcriptional regulation generates from protein-DNA interactions within the cell nucleus we have investigated the initial cellular response to exogenous ACE and the putative internalization of the enzyme in smooth muscle cells (SMC) and endothelial cells (EC). The following phenomena were observed when ACE was added to cells in culture: 1) it bound to SMC and EC with high affinity (Kd = 361.5 ± 60.5 pm) and with a low binding occupancy (Bmax = 335.0 ± 14.0 molecules/cell); 2) it triggered cellular signaling resulting in late activation of focal adhesion kinase and SHP2; 3) it modulated platelet-derived growth factor receptor-β signaling; 4) it was endocytosed by SMC and EC; and 5) it transited through the early endosome, partially occupied the late endosome and the lysosome, and was localized to the nuclei. The incorporation of ACE or a fragment of it into the nuclei reached saturation at 120 min, and was preceded by a lag time of 40 min. Internalized ACE was partially cleaved into small fragments. These results revealed that extracellular ACE modulated cell signaling properties, and that SMC and EC have a pathway for delivery of extracellular ACE to the nucleus, most likely involving cell surface receptor(s) and requiring transit through late endosome/lysosome compartments. PMID:20022959

  11. Conditional inactivation of TNFα-converting enzyme in chondrocytes results in an elongated growth plate and shorter long bones.

    PubMed

    Saito, Kenta; Horiuchi, Keisuke; Kimura, Tokuhiro; Mizuno, Sakiko; Yoda, Masaki; Morioka, Hideo; Akiyama, Haruhiko; Threadgill, David; Okada, Yasunori; Toyama, Yoshiaki; Sato, Kazuki

    2013-01-01

    TNFα-converting enzyme (TACE) is a membrane-bound proteolytic enzyme with essential roles in the functional regulation of TNFα and epidermal growth factor receptor (EGFR) ligands. Previous studies have demonstrated critical roles for TACE in vivo, including epidermal development, immune response, and pathological neoangiogenesis, among others. However, the potential contribution of TACE to skeletal development is still unclear. In the present study, we generated a Tace mutant mouse in which Tace is conditionally disrupted in chondrocytes under the control of the Col2a1 promoter. These mutant mice were fertile and viable but all exhibited long bones that were approximately 10% shorter compared to those of wild-type animals. Histological analyses revealed that Tace mutant mice exhibited a longer hypertrophic zone in the growth plate, and there were fewer osteoclasts at the chondro-osseous junction in the Tace mutant mice than in their wild-type littermates. Of note, we found an increase in osteoprotegerin transcripts and a reduction in Rankl and Mmp-13 transcripts in the TACE-deficient cartilage, indicating that dysregulation of these genes is causally related to the skeletal defects in the Tace mutant mice. Furthermore, we also found that phosphorylation of EGFR was significantly reduced in the cartilage tissue lacking TACE, and that suppression of EGFR signaling increases osteoprotegerin transcripts and reduces Rankl and Mmp-13 transcripts in primary chondrocytes. In accordance, chondrocyte-specific abrogation of Egfr in vivo resulted in skeletal defects nearly identical to those observed in the Tace mutant mice. Taken together, these data suggest that TACE-EGFR signaling in chondrocytes is involved in the turnover of the growth plate during postnatal development via the transcriptional regulation of osteoprotegerin, Rankl, and Mmp-13.

  12. Brain-targeted angiotensin-converting enzyme 2 overexpression attenuates neurogenic hypertension by inhibiting cyclooxygenase-mediated inflammation.

    PubMed

    Sriramula, Srinivas; Xia, Huijing; Xu, Ping; Lazartigues, Eric

    2015-03-01

    Overactivity of the renin-angiotensin system, oxidative stress, and cyclooxygenases (COX) in the brain are implicated in the pathogenesis of hypertension. We previously reported that angiotensin-converting enzyme 2 (ACE2) overexpression in the brain attenuates the development of deoxycorticosterone acetate-salt hypertension, a neurogenic hypertension model with enhanced brain renin-angiotensin system and sympathetic activity. To elucidate the mechanisms involved, we investigated whether oxidative stress, mitogen-activated protein kinase signaling and cyclooxygenase (COX) activation in the brain are modulated by ACE2 in neurogenic hypertension. Deoxycorticosterone acetate-salt hypertension significantly increased expression of Nox-2 (+61±5%), Nox-4 (+50±13%), and nitrotyrosine (+89±32%) and reduced activity of the antioxidant enzymes, catalase (-29±4%) and superoxide dismutase (-31±7%), indicating increased oxidative stress in the brain of nontransgenic mice. This increased oxidative stress was attenuated in transgenic mice overexpressing ACE2 in the brain. Deoxycorticosterone acetate-salt-induced reduction of neuronal nitric oxide synthase expression (-26±7%) and phosphorylated endothelial nitric oxide synthase/total endothelial nitric oxide synthase (-30±3%), and enhanced phosphorylation of protein kinase B and extracellular signal-regulated kinase 1/2 in the paraventricular nucleus, were reversed by ACE2 overexpression. In addition, ACE2 overexpression blunted the hypertension-mediated increase in gene and protein expression of COX-1 and COX-2 in the paraventricular nucleus. Furthermore, gene silencing of either COX-1 or COX-2 in the brain, reduced microglial activation and accompanied neuroinflammation, ultimately attenuating Deoxycorticosterone acetate-salt hypertension. Together, these data provide evidence that brain ACE2 overexpression reduces oxidative stress and COX-mediated neuroinflammation, improves antioxidant and nitric oxide signaling, and

  13. Interleukin-1 beta-converting enzyme-like protease cleaves DNA- dependent protein kinase in cytotoxic T cell killing

    PubMed Central

    1996-01-01

    Cytotoxic T cells (CTL) represent the major defense mechanism against the spread of virus infection. It is believed that the pore-forming protein, perforin, facilitates the entry of a series of serine proteases (particularly granzyme B) into the target cell which ultimately leads to DNA fragmentation and apoptosis. We demonstrate here that during CTL-mediated cytolysis the catalytic subunit of DNA- dependent protein kinase (DNA-PKcs), an enzyme implicated in the repair of double strand breaks in DNA, is specifically cleaved by an interleukin (IL)-1 beta-converting enzyme (ICE)-like protease. A serine protease inhibitor, 3,4-dichloroisocoumarin (DCl), which is known to block granzyme B activity, inhibited CTL-induced apoptosis and prevented the degradation of DNA-PKcs in cells but failed to prevent the degradation of purified DNA-PKcs by CTL extracts. However, Tyr-Val- Ala-Asp-CH2Cl (YVAD-CMK) and other cysteine protease inhibitors prevented the degradation of purified DNA-PKcs by CTL extracts. Furthermore, incubation of DNA-PKcs with granzyme B did not produce the same cleavage pattern observed in cells undergoing apoptosis and when this substrate was incubated with either CTL extracts or the ICE-like protease, CPP32. Sequence analysis revealed that the cleavage site in DNA-PKcs during CTL killing was the same as that when this substrate was exposed to CPP32. This study demonstrates for the first time that the cleavage of DNA-PKcs in this intact cell system is exclusively due to an ICE-like protease. PMID:8760815

  14. Increased angiotensin-I converting enzyme gene expression in the failing human heart. Quantification by competitive RNA polymerase chain reaction.

    PubMed Central

    Studer, R; Reinecke, H; Müller, B; Holtz, J; Just, H; Drexler, H

    1994-01-01

    Local activation of the components of the renin angiotensin system in the heart is regarded as an important modulator of cardiac phenotype and function; however, little is known about their presence, regulation, and potential activation in the human heart. To investigate the gene expression of major angiotensin-II-forming enzymes in left ventricles of normal (n = 9) and failing human hearts (n = 20), we established a competitive RNA-polymerase chain reaction (PCR) for mRNA quantification of angiotensin-I converting enzyme (ACE) and human heart chymase. For each gene, competitor RNA targets with small internal deletions were used as internal standards to quantify the original number of transcripts and to control reverse transcription and PCR. In PCR, each target and the corresponding competitor were amplified by competing for the same primer oligonucleotides. The variability of ACE RNA-PCR was 11% indicating a high reproducibility of this method. In addition, ACE mRNA levels obtained by competitive RNA-PCR correlated favorably with traditional slot blot hybridization (r = 0.69, n = 10; P < 0.05). Compared with nonfailing hearts, the number of ACE transcripts referred to 100 ng of total RNA was increased threefold in patients with chronic heart failure (4.2 +/- 2.5 vs. 12.8 +/- 6 x 10(5); P < 0.0005). In contrast, no significant difference was found in chymase gene expression between normal and failing hearts. Thus, the expression of the cardiac ACE but not of human heart chymase is upregulated in failing human heart indicating an activation of the cardiac renin-angiotensin system in patients with advanced heart failure. Images PMID:8040271

  15. Angiotensin-converting enzyme of the human small intestine. Subunit and quaternary structure, biosynthesis and membrane association.

    PubMed Central

    Naim, H Y

    1992-01-01

    Angiotensin-converting enzyme (ACE) was isolated from detergent-derived extracts of human intestinal brush-border membranes (BBMs) by immunoprecipitation using a monoclonal antibody. Analysis of the immunoprecipitates by SDS/PAGE revealed a polypeptide of apparent M(r) 184,000 under reducing and non-reducing conditions, indicating that ACE does not contain intermolecular disulphide bridges. The quaternary structure of ACE was examined using cross-linking experiments with dithiobis[succinimidylpropionate] (DSP) and density gradient centrifugation on sucrose gradients. Both approaches demonstrated that ACE is assembled in the membrane as a monomer. By contrast, the control glycoprotein aminopeptidase N (ApN) exists as a dimer. Biosynthetic labelling experiments in intestinal tissue explants demonstrated that the 184,000-M(r) protein is generated from a single-polypeptide, mannose-rich precursor of ACE (M(r) 175,000) by modification of the carbohydrate side-chains in the Golgi apparatus. The mode of association of the mature form of the enzyme with BBMs was investigated by hydrophobic labelling of right-side-out brush-border vesicles with the photoactivatable carbene-generating reagent 125I-labelled 3-(trifluoromethyl)-3-(m[formylamino]phenyl)diazirine (125I-labelled TID), followed by treatment with trypsin at dilutions that do not cause substantial degradation of ACE. These studies demonstrated that ACE is associated with the membrane via a hydrophobic segment. Furthermore, treatment of 35S-labelled inside-out membrane vesicles with trypsin revealed that ACE possesses a cytoplasmic tail, and therefore has a transmembraneous orientation. Images Fig. 1. Fig. 2. Fig. 3. Fig. 4. Fig. 5. Fig. 6. PMID:1326943

  16. Angiotensin-converting enzyme inhibitors-induced angioedema treated by C1 esterase inhibitor concentrate (Berinert®): about one case and review of the therapeutic arsenal.

    PubMed

    Lipski, Samuel Michael; Casimir, Georges; Vanlommel, Martine; Jeanmaire, Mathieu; Dolhen, Pierre

    2015-02-01

    C1 esterase inhibitor (Berinert®) is generally used to treat severe attack of hereditary angioedema. We describe here the case of a patient who presented with a severe angioedema induced by angiotensin-converting enzyme inhibitors (ACEIs) endangering her life. It could be successfully treated with that medicine.

  17. Short communication: Measuring the angiotensin-converting enzyme inhibitory activity of an 8-amino acid (8mer) fragment of the C12 antihypertensive peptide

    Technology Transfer Automated Retrieval System (TEKTRAN)

    An eight amino acid fragment (PFPEVFGK) of a known milk protein-derived antihypertensive peptide was synthesized by microwave-assisted solid phase peptide synthesis and purified by reverse phase HPLC. Its ability to inhibit the angiotensin-converting enzyme was assessed and compared to that of the ...

  18. Relationship between Angiotensin Converting Enzyme, Apelin, and New-Onset Atrial Fibrillation after Off-Pump Coronary Artery Bypass Grafting

    PubMed Central

    Xu, Shu; Zhang, Jian; Xu, Yin-li; Wu, Hai-bo; Xue, Xiao-dong

    2017-01-01

    It has been shown that inflammation and oxidative stress are important factors in postoperative atrial fibrillation (POAF). Angiotensin converting enzyme (ACE) and apelin have a close relationship with inflammation and oxidative stress. The effect of ACE and apelin on POAF after off-pump coronary artery bypass grafting (OPCABG) remains a question. The concentrations of serum ACE, angiotensin II (Ang II), apelin, bradykinin (BK), malondialdehyde (MDA), and C reactive protein (CRP) were measured in the perioperative period of OPCABG. The levels of serum ACE in the POAF group were higher than in the no POAF group both preoperatively and postoperatively. Apelin in the POAF group was lower than in the no POAF group. There was a correlation between serum ACE and apelin. Postoperatively, CRP and MDA in the POAF group were higher than in the no POAF group; however, there was no difference before the operation. Preoperative ACE and apelin were both significant and independent risk factors for POAF. In conclusion, the high ACE and low apelin preoperatively led to CRP and MDA being increased postoperatively, which was probably associated with POAF after OPCABG. Apelin may be a new predictor for POAF. PMID:28299332

  19. Genetic Polymorphism of Angiotensin-Converting Enzyme and Chronic Obstructive Pulmonary Disease Risk: An Updated Meta-Analysis

    PubMed Central

    Kang, Sang Wook; Kim, Su Kang; Jung, Hee-Jae; Kim, Kwan-Il; Kim, Jinju

    2016-01-01

    The relationship between polymorphism of the angiotensin I converting enzyme (ACE) gene and chronic obstructive pulmonary disease (COPD) has been examined in many previous studies. However, their results were controversial. Therefore, we performed a meta-analysis to evaluate the relationship between the ACE gene and the risk of COPD. Fourteen case-control studies were included in this meta-analysis. The pooled p value, odds ratio (OR), and 95% confidence interval (95% CI) were used to investigate the strength of the association. The meta-analysis was performed using comprehensive meta-analysis software. Our meta-analysis results revealed that ACE polymorphisms were not related to the risk of COPD (p > 0.05 in each model). In further analyses based on ethnicity, we observed an association between insertion/deletion polymorphism of the ACE gene and risk of COPD in the Asian population (codominant 2, OR = 3.126, 95% CI = 1.919–5.093, p < 0.001; recessive, OR = 3.326, 95% CI = 2.190–5.050, p < 0.001) but not in the Caucasian population (p > 0.05 in each model). In conclusion, the present meta-analysis indicated that the insertion/deletion polymorphism of the ACE gene may be associated with susceptibility to COPD in the Asian population but not in the Caucasian population. However, the results of the present meta-analysis need to be confirmed in a larger sample. PMID:27830153

  20. Association of angiotensin-converting enzyme I gene I/D polymorphism with endometrial but not with ovarian cancer.

    PubMed

    Correa-Noronha, Silvana Aparecida Alves; Noronha, Samuel Marcos Ribeiro de; Alecrim, Cheryl; Mesquita, Adriana de Carvalho; Brito, Gabriela Soares da Silva; Junqueira, Michele Gilvana; Leite, Daniela Batista; Carvalho, Cristina Valletta de; Silva, Ismael Dale Cotrim Guerreiro da

    2012-11-01

    Associations have been found between the angiotensin-converting enzyme insertion deletion (I/D) polymorphism (ACE I/D) and endometrial and epithelial ovarian cancer (EC and EOC, respectively). In this study, the following frequencies for each of three ACE polymorphisms, DD, ID, and II, respectively, were observed: in the EC group, 55, 24, and 21% versus the control group 39, 40, and 21% (p = 0.033*); in the EOC group 49, 36, and 15% versus the control group 49, 33, and 18% (p = 0.82). According to these allelic distributions, DD carriers are 2.0 times more likely than individuals carrying the ID or II genotypes to develop EC; therefore, the DD genotype seems to be protective against EC. In contrast, no association was observed between ACE (I/D) polymorphism with EOC. The ACE (I/D) polymorphism might play a role in the pathogenesis of EC and it should be considered when identifying genetic markers for EC.

  1. A Variant in XPNPEP2 Is Associated with Angioedema Induced by Angiotensin I–Converting Enzyme Inhibitors

    PubMed Central

    Duan, Qing Ling; Nikpoor, Borzoo; Dubé, Marie-Pierre; Molinaro, Giuseppe; Meijer, Inge A.; Dion, Patrick; Rochefort, Daniel; Saint-Onge, Judith; Flury, Leah; Brown, Nancy J.; Gainer, James V.; Rouleau, Jean L.; Agostoni, Angelo; Cugno, Massimo; Simon, Pierre; Clavel, Pierre; Potier, Jacky; Wehbe, Bassem; Benarbia, Seddik; Marc-Aurèle, Julien; Chanard, Jacques; Foroud, Tatiana; Adam, Albert; Rouleau, Guy A.

    2005-01-01

    Angiotensin I–converting enzyme inhibitors (ACEi), which are used to treat common cardiovascular diseases, are associated with a potentially life-threatening adverse reaction known as angioedema (AE-ACEi). We have previously documented a significant association between AE-ACEi and low plasma aminopeptidase P (APP) activity. With eight large pedigrees, we hereby demonstrate that this quantitative trait is partially regulated by genetic factors. We tested APP activity using a variance-component QTL analysis of a 10-cM genomewide microsatellite scan enriched with seven markers over two candidate regions. We found significant linkage (LOD = 3.75) to a locus that includes the XPNPEP2 candidate gene encoding membrane-bound APP. Mutation screening of this QTL identified a large coding deletion segregating in one pedigree and an upstream single-nucleotide polymorphism (C–2399A SNP), which segregates in the remaining seven pedigrees. Measured genotype analysis strongly suggests that the linkage signal for APP activity at this locus is accounted for predominantly by the SNP association. In a separate case-control study (20 cases and 60 controls), we found significant association of this SNP to ACEi-induced AE (P=.0364). In conclusion, our findings provide supporting evidence that the C-2399A variant in XPNPEP2 is associated with reduced APP activity and a higher incidence of AE-ACEi. PMID:16175507

  2. Novel approach of molecular genetic understanding of iridology: relationship between iris constitution and angiotensin converting enzyme gene polymorphism.

    PubMed

    Um, Jae-Young; An, Nyeon-Hyoung; Yang, Gui-Bi; Lee, Geon-Mok; Cho, Ju-Jang; Cho, Jae-Woon; Hwang, Woo-Jun; Chae, Han-Jung; Kim, Hyung-Ryong; Hong, Seung-Heon; Kim, Hyung-Min

    2005-01-01

    Iridology is the study of the iris of the eye to detect the conditions of the body and its organs, genetic strengths and weaknesses, etc. Although iridology is not widely used as a scientific tool for healthcare professionals to get to the source of people's health conditions, it has been used as a supplementary source to help the diagnosis of medical conditions by noting irregularities of the pigmentation in the iris among some Korean Oriental medical doctors. Angiotensin converting enzyme (ACE) gene polymorphism is one of the most well studied genetic markers of vascular disease. We investigated the relationship between iridological constitution and ACE polymorphism in hypertensives. We classified 87 hypertensives and 79 controls according to iris constitution and determined the ACE genotype of each individual. DD genotype was more prevalent in patients with a neurogenic constitution than in controls. This finding supports the hypothesis that D allele is a candidate gene for hypertension and demonstrates the association among ACE genotype, Korean hypertensives and iris constitution.

  3. Identification of Angiotensin I-Converting Enzyme Inhibitory Peptides Derived from Enzymatic Hydrolysates of Razor Clam Sinonovacula constricta

    PubMed Central

    Li, Yun; Sadiq, Faizan A.; Fu, Li; Zhu, Hui; Zhong, Minghua; Sohail, Muhammad

    2016-01-01

    Angiotensin I-converting enzyme (ACE) inhibitory activity of razor clam hydrolysates produced using five proteases, namely, pepsin, trypsin, alcalase, flavourzyme and proteases from Actinomucor elegans T3 was investigated. Flavourzyme hydrolysate showed the highest level of degree of hydrolysis (DH) (45.87%) followed by A. elegans T3 proteases hydrolysate (37.84%) and alcalase (30.55%). The A. elegans T3 proteases was observed to be more effective in generating small peptides with ACE-inhibitory activity. The 3 kDa membrane permeate of A. elegans T3 proteases hydrolysate showed the highest ACE-inhibitory activity with an IC50 of 0.79 mg/mL. After chromatographic separation by Sephadex G-15 gel filtration and reverse phase-high performance liquid chromatography, the potent fraction was subjected to MALDI/TOF-TOF MS/MS for identification. A novel ACE-inhibitory peptide (VQY) was identified exhibiting an IC50 of 9.8 μM. The inhibitory kinetics investigation by Lineweaver-Burk plots demonstrated that the peptide acts as a competitive ACE inhibitor. The razor clam hydrolysate obtained by A. elegans T3 proteases could serve as a source of functional peptides with ACE-inhibitory activity for physiological benefits. PMID:27271639

  4. Preparation and characterization of novel bioactive peptides responsible for angiotensin I-converting enzyme inhibition from wheat germ.

    PubMed

    Matsui, T; Li, C H; Osajima, Y

    1999-07-01

    Reported is the preparation of wheat germ (WG) hydrolyzate with potent angiotensin I-converting enzyme (ACE) inhibitory activity, and the characterization of peptides responsible for ACE inhibition. Successful hydrolyzate with the most potent ACE inhibitory activity was obtained by 0.5 wt.%-8 h Bacillus licheniformis alkaline protease hydrolysis after 3.0 wt.%-3 h alpha-amylase treatment of defatted WG (IC50; 0.37 mg protein ml(-1)). The activity of WG hydrolyzate was markedly increased by ODS and subsequent AG50W purifications (IC50; 0.018 mg protein ml(-1)). As a result of isolations by high performance liquid chromatographies, 16 peptides with the IC50 value of less than 20 microM, composed of 2-7 amino acid residues were identified from the WG hydrolyzate. Judging from the high content (260 mg in 100 g of AG50W fraction) and powerful ACE inhibitory activity (IC50; 0.48 microM), Ile-Val-Tyr was identified as a main contributor to the ACE inhibition of the hydrolyzate.

  5. Antioxidant and Angiotensin-Converting Enzyme Inhibitory Activity of Eucalyptus camaldulensis and Litsea glaucescens Infusions Fermented with Kombucha Consortium

    PubMed Central

    Gamboa-Gómez, Claudia I.; González-Laredo, Rubén F.; Gallegos-Infante, José Alberto; Pérez, MŞ del Mar Larrosa; Moreno-Jiménez, Martha R.; Flores-Rueda, Ana G.

    2016-01-01

    Summary Physicochemical properties, consumer acceptance, antioxidant and angiotensin-converting enzyme (ACE) inhibitory activities of infusions and fermented beverages of Eucalyptus camaldulensis and Litsea glaucescens were compared. Among physicochemical parameters, only the pH of fermented beverages decreased compared with the unfermented infusions. No relevant changes were reported in consumer preference between infusions and fermented beverages. Phenolic profile measured by UPLC MS/MS analysis demonstrated significant concentration changes of these compounds in plant infusions and fermented beverages. Fermentation induced a decrease in the concentration required to stabilize 50% of DPPH radical (i.e. lower IC50). Additionally, it enhanced the antioxidant activity measured by the nitric oxide scavenging assay (14% of E. camaldulensis and 49% of L. glaucescens); whereas relevant improvements in the fermented beverage were not observed in the lipid oxidation assay compared with unfermented infusions. The same behaviour was observed in the inhibitory activity of ACE; however, both infusions and fermented beverages had lower IC50 than positive control (captopril). The present study demonstrated that fermentation has an influence on the concentration of phenolics and their potential bioactivity. E. camaldulensis and L. glaucescens can be considered as natural sources of biocompounds with antihypertensive potential used either as infusions or fermented beverages. PMID:27956869

  6. High association of angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism with recurrent aphthous stomatitis.

    PubMed

    Karakus, Nevin; Yigit, Serbulent; Kalkan, Goknur; Sezer, Saime

    2013-08-01

    Recurrent aphthous stomatitis (RAS) is a common ulcerative disease of the oral mucosa. Oral ulcers are also the most common feature of Behçet's disease (BD). Association of angiotensin-converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism with BD has been reported in Turkish population. The aim of the present study was to investigate the possible association between ACE gene I/D polymorphism and RAS, and evaluate if there was an association with clinical features in a relatively large cohort of Turkish patients. The study included 198 patients affected by RAS and 214 healthy controls. ACE gene I/D polymorphism genotypes were determined using polymerase chain reaction with I and D allele-specific primers. The genotype and allele frequencies of I/D polymorphism showed statistically significant differences between RAS patients and controls (p < 0.0001 and p < 0.0001, respectively). After stratifying RAS patients according to clinical and demographical characteristics, no significant association was observed. In conclusion, the results of this study suggest that I/D polymorphism of the ACE gene was positively associated with predisposition to develop RAS in Turkish population. Further studies with larger populations are recommended.

  7. Phytochemical screening and evaluation of in vitro angiotensin-converting enzyme inhibitory activity of Artocarpus altilis leaf.

    PubMed

    Siddesha, Jalahalli M; Angaswamy, Nataraju; Vishwanath, Bannikuppe S

    2011-12-01

    This study investigates the effect of Artocarpus altilis leaf extracts on angiotensin-converting enzyme (ACE) activity. Among the extracts tested, hot ethanol extract exhibited a potent ACE-inhibitory activity with an IC₅₀ value of 54.08 ± 0.29 µg mL⁻¹ followed by cold ethyl acetate extract (IC₅₀ of 85.44 ± 0.85 µg mL⁻¹). In contrast, the hot aqueous extracts showed minimum inhibition with the IC₅₀ value of 765.52 ± 11.97 µg mL⁻¹ at the maximum concentration tested. Further, the phytochemical analysis indicated the varied distribution of tannins, phenolics, glycosides, saponins, steroids, terpenoids and anthraquinones in cold and hot leaf extracts. The correlation between the phytochemical analysis and ACE-inhibitory activity suggests that the high content of glycosidic and phenolic compounds could be involved in exerting ACE-inhibitory activity. In conclusion, this study supports the utilisation of A. altilis leaf in the folk medicine for the better treatment of hypertension. Further studies on isolation and characterisation of specific ACE-inhibitory molecule(s) from ethyl acetate, ethanol and methanol extracts of A. altilis leaf would be highly interesting.

  8. Antioxidant, Liver Protective and Angiotensin I-converting Enzyme Inhibitory Activities of Old Laying Hen Hydrolysate in Crab Meat Analogue.

    PubMed

    Jin, Sang Keun; Choi, Jung Seok; Choi, Yeung Joon; Lee, Seung-Jae; Lee, Seung Yun; Hur, Sun Jin

    2016-12-01

    The purpose of this study was to evaluate the antioxidative activities of Crab meat analogue prepared with protein hydrolysates obtained from mechanically deboned chicken meat (MDCM) from spent laying hens. 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH) radical-scavenging activity was increased by adding MDCM hydrolysates during storage, and activity correlated with the concentration of DPPH added up to 6 weeks of storage. Hydroxyl radical-scavenging activity was increased in all analogues containing MDCM hydrolysates. At 0 days of storage, angiotensin I-converting enzyme (ACE)-inhibitory activity was increased by the addition of MDCM hydrolysates. Activity did not correlate after 6 weeks of storage, in which ACE-inhibitory activity was increased with low concentrations of MDCM hydrolysates, but no ACE-inhibitory activity was observed at higher concentrations. The liver-protecting activity of crab meat analogue was shown to be around 60% of the positive control; however, it was not significantly different among the samples during storage. These results support the use of MDCM as a source of health-promoting constituents in crab meat analogue.

  9. Hydrolysates of sheep cheese whey as a source of bioactive peptides with antioxidant and angiotensin-converting enzyme inhibitory activities.

    PubMed

    Corrêa, Ana Paula Folmer; Daroit, Daniel Joner; Fontoura, Roberta; Meira, Stela Maris Meister; Segalin, Jeferson; Brandelli, Adriano

    2014-11-01

    Enzymatic proteolysis may be employed to release bioactive peptides, which have been investigated for potential benefits from both technological and human health perspectives. In this study, sheep cheese whey (SCW) was hydrolyzed with a protease preparation from Bacillus sp. P7, and the hydrolysates were evaluated for antioxidant and angiotensin I-converting enzyme (ACE)-inhibitory activities. Soluble protein and free amino acids increased during hydrolysis of SCW for up to 4h. Antioxidant activity of hydrolysates, evaluated by the 2,2'azino-bis-(3-ethylbenzothiazoline)-6-sulfonic acid radical scavenging method, increased 3.2-fold from 0 h (15.9%) to 6h of hydrolysis (51.3%). Maximum Fe(2+) chelation was reached in 3h hydrolysates, and the reducing power peaked at 1h of hydrolysis, representing 6.2 and 2.1-fold increase, respectively, when compared to that of non-hydrolyzed SCW. ACE inhibition by SCW (12%) was improved through hydrolysis, reaching maximal values (55% inhibition) in 4h, although 42% inhibition was already observed after 1h hydrolysis. The peptide LAFNPTQLEGQCHV, derived from β-lactoglobulin, was identified from 4-h hydrolysates. Such a biotechnological approach might be an interesting strategy for SCW processing, potentially contributing to the management and valorization of this abundant dairy byproduct.

  10. Identification of Angiotensin I-Converting Enzyme Inhibitory Peptides Derived from Enzymatic Hydrolysates of Razor Clam Sinonovacula constricta.

    PubMed

    Li, Yun; Sadiq, Faizan A; Fu, Li; Zhu, Hui; Zhong, Minghua; Sohail, Muhammad

    2016-06-03

    Angiotensin I-converting enzyme (ACE) inhibitory activity of razor clam hydrolysates produced using five proteases, namely, pepsin, trypsin, alcalase, flavourzyme and proteases from Actinomucor elegans T3 was investigated. Flavourzyme hydrolysate showed the highest level of degree of hydrolysis (DH) (45.87%) followed by A. elegans T3 proteases hydrolysate (37.84%) and alcalase (30.55%). The A. elegans T3 proteases was observed to be more effective in generating small peptides with ACE-inhibitory activity. The 3 kDa membrane permeate of A. elegans T3 proteases hydrolysate showed the highest ACE-inhibitory activity with an IC50 of 0.79 mg/mL. After chromatographic separation by Sephadex G-15 gel filtration and reverse phase-high performance liquid chromatography, the potent fraction was subjected to MALDI/TOF-TOF MS/MS for identification. A novel ACE-inhibitory peptide (VQY) was identified exhibiting an IC50 of 9.8 μM. The inhibitory kinetics investigation by Lineweaver-Burk plots demonstrated that the peptide acts as a competitive ACE inhibitor. The razor clam hydrolysate obtained by A. elegans T3 proteases could serve as a source of functional peptides with ACE-inhibitory activity for physiological benefits.

  11. Polymorphism of Angiotensin-Converting Enzyme (rs4340) and Diabetic Nephropathy in Caucasians with Type 2 Diabetes Mellitus

    PubMed Central

    Šeruga, M; Makuc, J; Završnik, M; Cilenšek, I; Ekart, R; Petrovič, D

    2016-01-01

    Abstract Diabetic nephropathy (DN) is the leading cause of endstage renal disease (ESRD) in developed countries. Several environmental and genetic factors predict the development and progression of DN. The renin-angiotensin system was demonstrated to be involved in the development of DN. We evaluated the association between rs4340 of the angiotensin-converting enzyme (ACE) gene and DN in Caucasians with type 2 diabetes mellitus (T2DM) in 276 Slovenian patients with T2DM who had DN, and 375 patients without clinical signs of DN. Genetic analysis was performed with either standard polymerase chain reaction (PCR) (for rs4340). Results were analyzed using the χ2 test and multivariate logistic regression analyses. We found no association between rs4340 and DN. Cystatin C was significantly higher in the DN+ group (p <0.001) than in the DN group. Cystatin C was a better marker for the estimation of renal function than estimated glomerular filtration rate (eGFR) according to the modification diet in renal disease (MDRD) equation mL/ min. We concluded that there was no association between the rs4340 of the ACE gene and DN in Caucasian patients who have T2DM. PMID:28289586

  12. Effect of angiotensin-converting enzyme inhibitors on arterial stiffness in hypertension: systematic review and meta-analysis.

    PubMed

    Mallareddy, Madhavi; Parikh, Chirag R; Peixoto, Aldo J

    2006-06-01

    Arterial stiffness is an independent cardiovascular prognostic factor and is modulated by angiotensin-converting enzyme inhibitors (ACEIs). The authors performed a meta-analysis of clinical trials investigating the effects of ACEIs on pulse wave velocity (PWV) or augmentation index. The search included randomized clinical trials as well as uncontrolled studies that measured in-treatment changes in arterial stiffness. The authors performed separate analyses for carotid-femoral PWV, brachioradial PWV, and augmentation index. Average absolute and relative reduction in mean arterial pressure and PWV were -15.4 mm Hg and -13.04% and -1.15 m/s and -9.74% for carotid-femoral PWV studies; and -11.2 mm Hg and -9.3% and -1.9 m/s and -16.7% for brachioradial PWV studies. There was a greater reduction in augmentation index by ACEIs when compared with controls (-1.0% to -5.3%). The authors conclude that ACEIs have modest beneficial effects on arterial stiffness measured as PWV and augmentation index, and this effect is at least partly independent of changes in blood pressure.

  13. Antioxidant and Angiotensin-Converting Enzyme Inhibitory Activity of Eucalyptus camaldulensis and Litsea glaucescens Infusions Fermented with Kombucha Consortium.

    PubMed

    Gamboa-Gómez, Claudia I; González-Laredo, Rubén F; Gallegos-Infante, José Alberto; Pérez, Mş Del Mar Larrosa; Moreno-Jiménez, Martha R; Flores-Rueda, Ana G; Rocha-Guzmán, Nuria E

    2016-09-01

    Physicochemical properties, consumer acceptance, antioxidant and angiotensin-converting enzyme (ACE) inhibitory activities of infusions and fermented beverages of Eucalyptus camaldulensis and Litsea glaucescens were compared. Among physicochemical parameters, only the pH of fermented beverages decreased compared with the unfermented infusions. No relevant changes were reported in consumer preference between infusions and fermented beverages. Phenolic profile measured by UPLC MS/MS analysis demonstrated significant concentration changes of these compounds in plant infusions and fermented beverages. Fermentation induced a decrease in the concentration required to stabilize 50% of DPPH radical (i.e. lower IC50). Additionally, it enhanced the antioxidant activity measured by the nitric oxide scavenging assay (14% of E. camaldulensis and 49% of L. glaucescens); whereas relevant improvements in the fermented beverage were not observed in the lipid oxidation assay compared with unfermented infusions. The same behaviour was observed in the inhibitory activity of ACE; however, both infusions and fermented beverages had lower IC50 than positive control (captopril). The present study demonstrated that fermentation has an influence on the concentration of phenolics and their potential bioactivity. E. camaldulensis and L. glaucescens can be considered as natural sources of biocompounds with antihypertensive potential used either as infusions or fermented beverages.

  14. Antioxidant, Liver Protective and Angiotensin I-converting Enzyme Inhibitory Activities of Old Laying Hen Hydrolysate in Crab Meat Analogue

    PubMed Central

    Jin, Sang Keun; Choi, Jung Seok; Choi, Yeung Joon; Lee, Seung-Jae; Lee, Seung Yun; Hur, Sun Jin

    2016-01-01

    The purpose of this study was to evaluate the antioxidative activities of Crab meat analogue prepared with protein hydrolysates obtained from mechanically deboned chicken meat (MDCM) from spent laying hens. 2,2-diphenyl-1-picrylhydrazyl hydrate (DPPH) radical-scavenging activity was increased by adding MDCM hydrolysates during storage, and activity correlated with the concentration of DPPH added up to 6 weeks of storage. Hydroxyl radical-scavenging activity was increased in all analogues containing MDCM hydrolysates. At 0 days of storage, angiotensin I-converting enzyme (ACE)-inhibitory activity was increased by the addition of MDCM hydrolysates. Activity did not correlate after 6 weeks of storage, in which ACE-inhibitory activity was increased with low concentrations of MDCM hydrolysates, but no ACE-inhibitory activity was observed at higher concentrations. The liver-protecting activity of crab meat analogue was shown to be around 60% of the positive control; however, it was not significantly different among the samples during storage. These results support the use of MDCM as a source of health-promoting constituents in crab meat analogue. PMID:26954200

  15. Evaluation of the antioxidant properties of the angiotensin-converting enzyme inhibitor, captopril and the nucleotide enhancing agent, acadesine.

    PubMed

    Wasil, M; Kelly, F J

    1995-11-01

    The angiotensin-converting enzyme inhibitor, captopril and the nucleotide enhancing agent, acadesine, protect myocardial tissue from ischaemia/reperfusion-induced injury. Although both drugs have well established, independent mechanisms of cardiac protection, they may also have antioxidant activity which could contribute to their beneficial action. In this study we have examined the antioxidant activity of captopril and acadesine by examining their ability to scavenge ABTS radicals, formed from the interaction of ferryl metmyoglobin with phenothiazine in the presence of hydrogen peroxide. For comparison, we compared these results to those obtained for a range of other drugs commonly used for the treatment of cardiovascular disorders. These included verapamil (arrhythmia), isosorbide dinitrate (angina), atenolol (hypertension) and enalapril (congestive heart failure). The antioxidant properties of these drugs were then compared to the well characterised antioxidants, Trolox (a water soluble vitamin E analogue), ascorbate and glutathione. Captopril and acadesine were both shown to be efficient scavengers of ABTS radicals, importantly at drug concentrations expected to be found in vivo. These data confirm that the antioxidant potential of captopril and acadesine may be an important component of their mechanism of action, with both drugs probably protecting the myocardium against oxygen derived free radicals during ischaemia/reperfusion.

  16. Angiotensin-converting enzyme inhibitor-induced angioedema and hereditary angioedema: a comparison study of attack severity.

    PubMed

    Javaud, Nicolas; Charpentier, Stéphane; Lapostolle, Frédéric; Lekouara, Hakim; Boubaya, Marouane; Lenoir, Gilles; Mekinian, Arsène; Adnet, Frédéric; Fain, Olivier

    2015-01-01

    Objective There appears to be differences in the clinical presentation of hereditary angioedema (HAE) and angiotensin-converting enzyme inhibitor-induced (ACE-I) angioedema (AE). The aim of this study was to compare the clinical characteristics of these two AE forms. Methods We conducted a retrospective study of consecutive patients with HAE or ACE-I AE. The attack characteristics experienced by the patients were compared by a logistic regression analysis using generalized estimating equations. Results A total of 56 patients were included in this study (ACE-I AE, n=25; HAE, n=31). A total of 534 attacks were documented. Severe attacks were more common in the patients who had an acute episode of ACE-I AE than HAE. Swelling of the tongue, lips and larynx were significantly associated with ACE-I AE [OR: 8.70 (95% CI, 1.04-73.70), OR: 20.4 (95% CI, 4.9-84.2) and OR: 7.50 (95% CI, 1.20-48.30), respectively]. Conclusion Swelling of the tongue, lips and larynx are significantly more frequent in drug-induced AE than HAE.

  17. A comparative study of neuroprotective effect of angiotensin converting enzyme inhibitors against scopolamine-induced memory impairments in rats

    PubMed Central

    Jawaid, Talha; Jahan, Shah; Kamal, Mehnaz

    2015-01-01

    The comparative study of neuroprotective effect of angiotensin converting enzyme inhibitors against scopolamine-induced neuroinflammation in albino Wistar rats was studied. Male albino rats were administered with scopolamine to induce memory impairment. The standard nootropic agent, piracetam (200 mg/kg b.w., [i.p.]), perindopril (0.1 mg/kg b.w., [i.p.]), enalapril (0.1 mg/kg b.w., [i.p.]), and ramipril (0.1 mg/kg b.w., [i.p.]) were administered in different group of animals for 5 days. On 5th day, scopolamine (1 mg/kg b.w., i.p.) was administered after 60 min of the last dose of test drug. Memory function was evaluated in Morris water maze (MWM) test and pole climbing test (PCT). Biochemical estimations like glutathione (GSH), malondialdehyde (MDA), and acetylcholinesterase activity in the brain were estimated after completion of behavior study. All three test groups shows improvement in learning and memory in comparison to control group. Perindopril treated group showed a more effective significant decrease in escape latency time and transfer latency time compared to enalapril and ramipril treated group on day 4 in MWM test and PCT, respectively. Perindopril shows a significant reduction in MDA level and acetylcholinesterase activity and a significant rise in GSH level compared to enalapril and ramipril. The finding of this study indicates that Perindopril is more effective in memory retention compared to enalapril and ramipril. PMID:26317078

  18. Empirical and bioinformatic characterization of buffalo (Bubalus bubalis) colostrum whey peptides & their angiotensin I-converting enzyme inhibition.

    PubMed

    Ashok, N R; Aparna, H S

    2017-08-01

    Whey based peptides are well known for their nutritional and multifunctional properties. In this context, whey proteins from buffalo colostrum & milk were digested by in vitro simulation digestion and analyzed by nano-LC-MS/MS. Functional protein association networks, gene annotations and localization of identified proteins were carried out. An ACE inhibitory peptide sorted from the library was custom synthesized and an in vitro ACE assay was performed. The study led to the identification of 74 small peptides which were clustered into 5 gene functional groups and majority of them were secretory proteins. Among the identified peptides, majority of them were found identical to angiotensin I-converting enzyme (ACE) inhibitors, antioxidant, antimicrobial, immunomodulatory and opioidal peptides. An octapeptide (m/z - 902.51, IQKVAGTW) synthesized was found to inhibit ACE with an IC50 of 300±2µM. The present investigation thus establishes newer vista for food derived peptides having ACE inhibitory potential for nutraceutical or therapeutic applications.

  19. Production, purification, and crystallization of human interleukin-1 beta converting enzyme derived from an Escherichia coli expression system.

    PubMed

    Malinowski, J J; Grasberger, B L; Trakshel, G; Huston, E E; Helaszek, C T; Smallwood, A M; Ator, M A; Banks, T M; Brake, P G; Ciccarelli, R B

    1995-10-01

    Interleukin-1 beta converting enzyme (ICE) is a cysteine protease that catalyzes the conversion of the inactive precursor form of IL-1 beta to an active mature form. The mature form of IL-1 beta is involved in mediating inflammatory responses and in the progression of autoimmune diseases. We recently reported on the production of active human ICE in insect cells using the baculovirus expression system (Wang XM et al., 1994, Gene 145:273-277). Because the levels of expression achieved with this system were limiting for the purpose of performing detailed biochemical and biophysical studies, we examined the production of ICE in Escherichia coli. By using a tac promoter-based expression system and fusion to thioredoxin we were able to recover high levels of active ICE protein. The expressed protein, which was distributed between the soluble and insoluble fractions, was purified to homogeneity from both fractions using a combination of classical and affinity chromatography. Comparisons of ICE derived from both fractions indicated that they were comparable in their specific activities, subunit composition, and sensitivities to specific ICE inhibitors. The combined yields of ICE obtained from the soluble and insoluble fractions was close to 1 mg/L of induced culture. Recombinant human ICE was crystallized in the presence of a specific ICE inhibitor in a form suitable for X-ray crystallographic analysis. This readily available source of ICE will facilitate the further characterization of this novel and important protease.

  20. Association of angiotensin converting enzyme gene insertion/deletion polymorphism and familial hypercholesterolemia in the Saudi population

    PubMed Central

    2013-01-01

    Background The study of the association between genotype and phenotype is of great importance for the prediction of multiple diseases and pathophysiological conditions. The relationship between angiotensin converting enzyme (ACE) Insertion/Deletion (I/D) polymorphism and Familial Hypercholesterolemia (FH) has been not fully investigated in all the ethnicities. In this study we sought to determine the frequency of I/D polymorphism genotypes of ACE gene in Saudi patients with FH. Results This is a case–control study carried out purely in Saudi population. Genomic DNA was isolated from 128 subjects who have participated in this study. ACE gene I/D polymorphism was analyzed by polymerase chain reaction in 64 FH cases and 64 healthy controls. There was no statistically significant difference between the groups with respect to genotype distribution. Furthermore, we did not find any significant difference in the frequency of ACE I/D polymorphism in FH subjects when stratified by gender (p = 0.43). Conclusion Our data suggest that ACE gene I/D polymorphism examined in this study has no role in predicting the occurrence and diagnosis of FH. PMID:24289455

  1. Antioxidant capacity and angiotensin I converting enzyme inhibitory activity of a melon concentrate rich in superoxide dismutase.

    PubMed

    Carillon, Julie; Del Rio, Daniele; Teissèdre, Pierre-Louis; Cristol, Jean-Paul; Lacan, Dominique; Rouanet, Jean-Max

    2012-12-01

    Antioxidant capacity and angiotensin 1-converting enzyme (ACE) inhibitory activity of a melon concentrate rich in superoxide dismutase (SOD-MC) were investigated in vitro. The total antioxidant capacity (TAC) was measured by the Trolox equivalent antioxidant capacity assay (TEAC), the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical assay, and the ferric reducing antioxidant power assay (FRAP). The ability of the extract to scavenge three specific reactive oxygen species (superoxide radical anion (O(2)(-)), hydroxyl radical (HO()) and hydrogen peroxide (H(2)O(2))) was also investigated in order to better evaluate its antioxidant properties. Even if the measures of TAC were relatively low, results clearly established an antioxidant potential of SOD-MC that exhibited the highest radical-scavenging activity towards O(2)(-), with a IC(50) 12-fold lower than that of H(2)O(2) or HO(). This lets hypothesis that the antioxidant potential of SOD-MC could be mainly due to its high level of SOD. Moreover, for the first time, an ACE inhibitory activity of SOD-MC (IC(50)=2.4±0.1mg/mL) was demonstrated, showing that its use as a functional food ingredient with potential preventive benefits in the context of hypertension may have important public health implications and should be carefully considered.

  2. Antihypertensive Effects of Artemisia scoparia Waldst in Spontaneously Hypertensive Rats and Identification of Angiotensin I Converting Enzyme Inhibitors.

    PubMed

    Cho, Jeong-Yong; Park, Kyung-Hee; Hwang, Do Young; Chanmuang, Saoraya; Jaiswal, Lily; Park, Yang-Kyun; Park, Sun-Young; Kim, So-Young; Kim, Haeng-Ran; Moon, Jae-Hak; Ham, Kyung-Sik

    2015-11-03

    We investigated the antihypertensive effects of Artemisia scoparia (AS) in spontaneously hypertensive rats (SHR). The rats were fed diets containing 2% (w/w) hot water extracts of AS aerial parts for 6 weeks. The AS group had significantly lower systolic and diastolic blood pressure levels than the control group. The AS group also had lower angiotensin I converting enzyme (ACE) activity and angiotensin II content in serum compared to the control group. The AS group showed higher vascular endothelial growth factor and lower ras homolog gene family member A expression levels in kidney compared to the control group. The AS group had significantly lower levels of plasma lipid oxidation and protein carbonyls than the control group. One new and six known compounds were isolated from AS by guided purification. The new compound was determined to be 4'-O-β-D-glucopyranoyl (E)-4-hydroxy-3-methylbut-2-enyl benzoate, based on its nuclear magnetic resonance and electrospray ionization-mass spectroscopy data.

  3. Changes in renal vessels associated with long-term administration of angiotensin converting enzyme inhibitor in Zucker fatty rats

    PubMed Central

    Nakanishi, Kazushige; Nagai, Yohko; Akimoto, Tatsuo; Yamanaka, Nobuaki

    2017-01-01

    Background Recently, we showed that long-term angiotensin receptor blocker (ARB) administration induced unusual proliferative changes in smooth muscle cells (SMCs) of afferent arterioles of the kidneys of Zucker fatty rats (ZFRs). In this study, we investigated renal afferent arteriolar changes induced by the long-term administration of an angiotensin converting enzyme inhibitor (ACEI) in ZFRs. Materials and Methods Fourteen 6-week-old male ZFRs were divided into two groups (n=14): the ZFR+ACEI group (n=6) was fed a standard diet containing ACEI (Enalapril, 2 mg/kg/day), and the ZFR control group (n=8) for 12 weeks. Blood pressure and proteinuria were examined and morphological studies on kidneys were performed. Results Remarkable proliferative changes in the afferent arteriolar SMCs were frequently observed in the group given ACEI; (66.1 ± 12.9%) compared with the control group (1.77 ± 1.56%, P<0.001). Conclusions It was indicated that long-term ACEI administration induced unusual proliferative changes in SMCs in afferent arterioles of ZFRs. These changes could reduce intraglomerular pressure by narrowing the lumens of afferent arterioles, but they could cause irreversible damage to the arterioles. PMID:28260705

  4. Sleep-related movement disorder symptoms in SHR are attenuated by physical exercise and an angiotensin-converting enzyme inhibitor.

    PubMed

    Frank, Miriam Kannebley; de Mello, Marco Tulio; Lee, Kil Sun; Daubian-Nosé, Paulo; Tufik, Sergio; Esteves, Andrea Maculano

    2016-02-01

    The relationship between hypertension and sleep-related movement disorders has been hypothesized for humans, but the causes and mechanisms have not been elucidated. We investigated whether an alteration in blood pressure (BP) induced by physical exercise and/or an angiotensin-converting enzyme inhibitor (enalapril) could affect locomotor activity in spontaneously hypertensive rats, with emphasis on the dopaminergic system. We used SHR and normotensive Wistar rats distributed into 4 groups for each strain: control, physical exercise, enalapril and physical exercise+enalapril. Physical exercise was performed on a treadmill, and enalapril was administered by gavage, both for 8weeks. During this period, locomotor activity was evaluated in an open field test, and BP was evaluated by tail plethysmography. Dopaminergic receptors, dopamine transporter and tyrosine hydroxylase levels at the striatum were evaluated by Western blotting. The control group of spontaneously hypertensive rats showed higher BP, increased activity in the open field test and lower levels of D2 receptors and tyrosine hydroxylase compared with all other groups throughout the experimental period. In general, physical exercise and enalapril attenuated these alterations. This study suggested the existence of comorbidity between hypertension and sleep-related movement disorders in spontaneously hypertensive rats. Physical exercise and enalapril conferred protection for both hypertension and the observed behavioral changes. In addition, these treatments led to changes in dopaminergic signaling in the striatal region (i.e., D2 receptor, TH and DAT).

  5. Effect of Angiotensin-Converting Enzyme Inhibitor, Lisinopril on Morphological and Biochemical Aspects of Fibrotic Liver Regeneration

    PubMed Central

    Ambreen, Aysha; Jahan, Sarwat; Malik, Satwat

    2016-01-01

    Background/Aims: Hepatic fibrosis results in defective liver regeneration following partial hepatectomy. Angiotensin converting enzyme (ACE) inhibitors can enhance liver regeneration and are also involved in the reduction of hepatic fibrosis. The present study has been conducted to evaluate the potential effect of an ACE inhibitor, lisinopril, on the morphological and biochemical aspects of fibrotic liver regeneration. Materials and Methods: Eight-week old female Sprague Dawley rats were made fibrotic by intragastric carbon tetrachloride treatment. Rats were given saline or lisinopril (1 mg/kg) orally for 1 week and were subjected to sham surgery or two-third partial hepatectomy. Liver regenerative and functional capacities were determined 48 hours post surgery. Results: Lisinopril administration did not affect the regeneration rate, proliferation cell nuclear antigen count, and hepatocellular area of fibrotic livers following partial hepatectomy. No statistically significant difference between treated and control rats regarding mitotic count, hepatocyte nuclear area, and binuclear hepatocyte frequency was observed. Serum biochemical analysis showed that lisinopril non-significantly decreased the partial hepatectomy induced elevated levels of alanine aminotransferase, aspartate transaminase, and alkaline phosphatase whereas lactate dehydrogenase and total bilirubin levels were significantly reduced. No marked reduction in hepatic collagen content and alpha smooth actin positive cells was observed by lisinopril treatment. Conclusion: ACE inhibitor lisinopril did not produce major histomorphological alterations in regenerating fibrotic liver following partial hepatectomy, however, it may improve its functional capability. PMID:27976638

  6. A unique geometry of the active site of angiotensin-converting enzyme consistent with structure-activity studies

    NASA Astrophysics Data System (ADS)

    Mayer, Dorica; Naylor, Christopher B.; Motoc, Ioan; Marshall, Garland R.

    1987-04-01

    Previous structure-activity studies of captopril and related active angiotensin-converting enzyme (ACE) inhibitors have led to the conclusion that the basic structural requirements for inhibition of ACE involve (a) a terminal carboxyl group; (b) an amido carbonyl group; and (c) different types of effective zinc (Zn) ligand functional groups. Such structural requirements common to a set of compounds acting at the same receptor have been used to define a pharmacophoric pattern of atoms or groups of atoms mutually oriented in space that is necessary for ACE inhibition from a stereochemical point of view. A unique pharmacophore model (within the resolution of approximately 0.15 Å) was observed using a method for systematic search of the conformational hyperspace available to the 28 structurally different molecules under study. The method does not assume a common molecular framework, and, therefore, allows comparison of different compounds that is independent of their absolute orientation. Consequently, by placing the carboxyl binding group, the binding site for amido carbonyl, and the Zn atom site in positions determined by ideal binding geometry with the inhibitors' functional groups, it was possible to clearly specify a geometry for the active site of ACE.

  7. Endothelin-converting enzyme-1 (ECE-1) is a downstream target of the homeobox transcription factor Nkx2-5.

    PubMed

    Funke-Kaiser, H; Lemmer, J; Langsdorff, C V; Thomas, A; Kovacevic, S D; Strasdat, M; Behrouzi, T; Zollmann, F S; Paul, M; Orzechowski, H-D

    2003-08-01

    The homeobox transcription factor Nkx2-5 and the zinc metalloprotease endothelin-converting enzyme-1 (ECE-1) are essential for cardiac development. Here, we demonstrate for the first time a functional link between Nkx2-5 and ECE-1. In transiently transfected rat H9c2 cardiomyoblasts, the alternative promoters specific for ECE-1a, ECE-1b, and ECE-1c are activated by Nkx2-5 coexpression. Lack of a consensus sequence for Nkx2-5 binding within the ECE-1c promoter and mutational analyses of Nkx2-5 consensus sequences identified in the ECE-1a and ECE-1b promoters, respectively, reveal an indirect mechanism of activation that is supported by gel shift assays. Furthermore, we have evidence of an additional direct activation mechanism of the ECE-1b promoter by Nkx2-5. With the use of RNase protection assay, Northern blot, and real-time PCR, the activating effect of Nkx2-5 on mRNA expression of ECE-1 isoforms was confirmed in the chromatin context of H9c2 and endothelial EA.hy926 cells, respectively, by stable Nkx2-5 overexpression. The interaction presented in this work provides a possible explanation for distinct phenotypic aspects of patients carrying mutations in the Nkx2-5 gene and may also be of significance for the pathophysiology of heart failure.

  8. The effects of phosphoramidon on the expression of human endothelin-converting enzyme-1 (ECE-1) isoforms.

    PubMed

    Isaka, Daiji; Emoto, Noriaki; Raharjo, Sunu Budhi; Yokoyama, Mitsuhiro; Matsuo, Masafumi

    2003-07-01

    Endothelin-1 (ET-1) is generated from big ET-1 by endothelin converting enzyme-1 (ECE-1). This process is inhibited by phosphoramidon through binding to the catalytic domain of ECE-1. There are four isoforms of human ECE-1 (ECE-1a, ECE-1b, ECE-1c and ECE-1d) which possess a conserved catalytic domain. Interestingly, a recent study has shown that in ECE-1b-transfected CHO cells phosphoramidon increases the expression and activity of ECE-1b. It is not known, however, whether phosphoramidon has similar effects on the expression of other ECE-1 isoforms. To address this point, we have established recombinant CHO cell lines that permanently express either human ECE-1a, ECE-1b or ECE-1c. Incubation of CHO/ECE-1a, -1b, and -1c with phosphoramidon (100 microM) for 16 hours markedly elevated the intracellular expression of ECE-1a and ECE-1b, but not ECE-1c protein, as indicated by Western blotting and immunocytochemistry. These increases appear to be due to inhibition of intracellular degradation of the protein because metabolic labeling followed by immunoprecipitation showed ECE-1a and ECE-1b proteins had prolonged half-lives in the phosphoramidon-treated cells. This is further supported by the finding that ECE-1 mRNA levels were unchanged following phosphoramidon treatment. Taken together, our results demonstrate that phosphoramidon differentially affects the expression of three human ECE-1 isoforms.

  9. On the role of endothelin-converting enzyme-1 (ECE-1) and neprilysin in human breast cancer.

    PubMed

    Smollich, Martin; Götte, Martin; Yip, George W; Yong, Eng-Siang; Kersting, Christian; Fischgräbe, Jeanett; Radke, Isabel; Kiesel, Ludwig; Wülfing, Pia

    2007-12-01

    Endothelin-1 (ET-1) and its receptors, ET(A)R and ET(B)R, are overexpressed in breast carcinomas. However, little is known about the relevance of endothelin-converting enzyme-1 (ECE-1) and ET-1 degrading neprilysin (NEP). In this study, expression of ECE-1 and NEP was determined in 600 breast cancer tissue samples by immunohistochemistry; staining results were correlated with clinicopathological parameters. For ECE-1 expression, we found a significant correlation with VEGF (P < 0.001) and ET(A)R expression (P = 0.048). While patients with ECE-1 overexpressing tumours had more frequent disease recurrence (P = 0.03), NEP overexpression correlated with improved disease-free survival (DFS) (P = 0.023) and less frequent metastasis (P = 0.046). Also, a decrease of NEP expression with malignant progression (G1-G3) was found. ECE-1 inhibition using the selective ECE-1 inhibitor RO 67-7447 in MCF-7 breast cancer cells led to a significantly decreased ET-1 expression and reduced cell invasiveness (54.3% of controls, P = 0.014). Our results indicate that overexpression of ECE-1 is associated with unfavourable outcome, whereas NEP positively influences survival. Thus, expression of ECE-1 and NEP may have prognostic relevance. Due to the anti-invasive effect of the selective ECE-1 inhibitor, targeting ECE-1 may represent an innovative option in future breast cancer therapy.

  10. Isoforms of endothelin-converting enzyme-1 (ECE-1) have opposing effects on prostate cancer cell invasion.

    PubMed

    Lambert, L A; Whyteside, A R; Turner, A J; Usmani, B A

    2008-10-07

    Cross-talk between tumour and stromal cells can profoundly influence cancer cell invasion by increasing the availability of mitogenic peptides such as endothelin-1 (ET-1). Endothelin-1 is elevated in men with metastatic prostate cancer (PC), and can exert both an autocrine (epithelial) and a paracrine (stromal) influence on growth. Endothelin-1 is generated from its inactive precursor big-ET-1 by endothelin-converting enzyme 1 (ECE-1). We and others have demonstrated that ECE-1 expression is significantly elevated in tumours and surrounding stromal tissue. Our current data show siRNA-mediated knockdown of stromal ECE-1 reduces epithelial (PC-3) cell invasion in coculture. Interestingly, readdition of ET-1 only partially recovers this effect suggesting a novel role for ECE-1 independent of ET-1 activation. Parallel knockdown of ECE-1 in both stromal and epithelial compartments results in an additive decrease in cell invasion. We extrapolated this observation to the four recognised isoforms ECE-1a, ECE-1b, ECE-1c and ECE-1d. Only ECE-1a and ECE-1c were significant but with reciprocal effects on cell invasion. Transient ECE-1c overexpression increased PC-3 invasiveness through matrigel, whereas transient ECE-1a expression suppressed invasion. Furthermore, transient ECE-1a expression in stromal cells strongly counteracts the effect of transient ECE-1c expression in PC-3 cells. The ECE-1 isoforms may, therefore, be relevant targets for antiinvasive therapy in prostate and other cancers.

  11. Angiotensin I-converting enzyme (ACE) activity and expression in rat central nervous system after sleep deprivation.

    PubMed

    Visniauskas, Bruna; Oliveira, Vitor; Carmona, Adriana K; D'Almeida, Vânia; de Melo, Robson L; Tufik, Sérgio; Chagas, Jair R

    2011-04-01

    Proteases are essential either for the release of neuropeptides from active or inactive proteins or for their inactivation. Neuropeptides have a fundamental role in sleep-wake cycle regulation and their actions are also likely to be regulated by proteolytic processing. Using fluorescence resonance energy transfer substrates, specific protease inhibitors and real-time PCR we demonstrate changes in angiotensin I-converting enzyme (ACE) expression and proteolytic activity in the central nervous system in an animal model of paradoxical sleep deprivation during 96 h (PSD). Male rats were distributed into five groups (PSD, 24 h, 48 h and 96 h of sleep recovery after PSD and control). ACE activity and mRNA levels were measured in hypothalamus, hippocampus, brainstem, cerebral cortex and striatum tissue extracts. In the hypothalamus, the significant decrease in activity and mRNA levels, after PSD, was only totally reversed after 96 h of sleep recovery. In the brainstem and hippocampus, although significant, changes in mRNA do not parallel changes in ACE specific activity. Changes in ACE activity could affect angiotensin II generation, angiotensin 1-7, bradykinin and opioid peptides metabolism. ACE expression and activity modifications are likely related to some of the physiological changes (cardiovascular, stress, cognition, metabolism function, water and energy balance) observed during and after sleep deprivation.

  12. LC-MS/MS quantification of bioactive angiotensin I-converting enzyme inhibitory peptides in rye malt sourdoughs.

    PubMed

    Hu, Ying; Stromeck, Achim; Loponen, Jussi; Lopes-Lutz, Daise; Schieber, Andreas; Gänzle, Michael G

    2011-11-23

    This study quantified antiotensin I-converting enzyme (ACE) inhibitory peptides in rye malt sourdoughs supplemented with gluten proteins and fermented with six strains of Lactobacillus spp. Bioinformatic analysis of prolamins from barley, rye, and wheat demonstrated that the ACE inhibitory peptides LQP, LLP, VPP, and IPP are frequently encrypted in their primary sequence. These tripeptides were quantified by liquid chromatography-tandem mass spectrometry. Tripeptide levels in sourdoughs were generally higher as compared to the chemically acidified controls. Sourdoughs fermented with different strains showed different concentrations of LQP and LLP. These differences corresponded to strain-specific differences in PepO and PepN activities. The highest levels of peptides VPP, IPP, LQP, and LLP, 0.23, 0.71, 1.09, and 0.09 mmol (kg DM)(-1), respectively, were observed in rye malt: gluten sourdoughs fermented with Lactobacillus reuteri TMW 1.106 and added protease. These concentrations were 6-7 times higher as compared to sourdough without fungal protease and exceed the IC(50) by 100-1000-fold.

  13. Reduction of microalbuminuria in type-2 diabetes mellitus with angiotensin-converting enzyme inhibitor alone and with cilnidipine.

    PubMed

    Singh, V K; Mishra, A; Gupta, K K; Misra, R; Patel, M L; Shilpa

    2015-01-01

    The aim of our study was to find out the antiproteinuric effect of enalapril angiotensin-converting enzyme (ACE inhibitor) alone or in combination with cilnidipine in patients with type-2 diabetes mellitus. The study was conducted on 71 patients with type-2 diabetes mellitus patients with hypertension and microalbuminuria. They were divided into two groups randomly as follows: Group I (enalaprilalone, n = 36) and Group II (enalapril with cilnidipine, n = 35). In both the groups, baseline 24 h urinary albumin was estimated and was repeated every 3 months upto 1-year. After 1-year follow-up, reduction in microalbuminuria was found to be greater in Group II. In Group I microalbuminuria came down by 25.68 ± 21.40 while in Group II it reduced by 54.88 ± 13.84 (P < 0.001). We conclude that in diabetic population, cilnidipine has an additive effect in microalbuminuria reduction over and above the well-proven effect of ACE inhibitors.

  14. Photoaffinity labeling of Ras converting enzyme 1 (Rce1p) using a benzophenone-containing peptide substrate.

    PubMed

    Kyro, Kelly; Manandhar, Surya P; Mullen, Daniel; Schmidt, Walter K; Distefano, Mark D

    2010-08-01

    Isoprenylation is a post-translational modification that increases protein hydrophobicity and helps target certain proteins to membranes. Ras converting enzyme 1 (Rce1p) is an endoprotease that catalyzes the removal of a three residue fragment from the C-terminus of isoprenylated proteins. To obtain structural information about this membrane protein, photoaffinity labeling agents are being prepared and employed. Here, we describe the synthesis of a benzophenone-containing peptide substrate analogue for Rce1p. Using a continuous spectrofluorometric assay, this peptide was shown to be a substrate for Rce1p. Mass spectrometry was performed to confirm the site of cleavage and structure of the processed probe. Photolysis of the biotinylated compound in the presence of membranes containing Rce1p followed by streptavidin pull-down and Western blot analysis indicated that Rce1p had been labeled by the probe. Photolysis in the presence of both the biotinylated, benzophenone-containing probe and a farnesylated peptide competitor reduced the extent of labeling, suggesting that labeling is occurring in the active site.

  15. Photoaffinity Labeling of Ras Converting Enzyme 1 (Rce1p) using a Benzophenone-Containing Peptide Substrate

    PubMed Central

    Kyro, Kelly; Manandhar, Surya P.; Mullen, Daniel; Schmidt, Walter K.; Distefano, Mark D.

    2010-01-01

    Isoprenylation is a post-translational modification that increases protein hydrophobicity and helps target certain proteins to membranes. Ras Converting Enzyme 1 (Rce1p) is an endoprotease that catalyzes the removal of a three residue fragment from the C-terminus of isoprenylated proteins. To obtain structural information about this membrane protein, photoaffinity labeling agents are being prepared and employed. Here, we describe the synthesis of a benzophenone-containing peptide substrate analogue for Rce1p. Using a continuous spectrofluorometric assay, this peptide was shown to be a substrate for Rce1p. Mass spectrometry was performed to confirm the site of cleavage and structure of the processed probe. Photolysis of the biotinylated compound in the presence of membranes containing Rce1p followed by streptavidin pull-down and Western blot analysis indicated that Rce1p had been labeled by the probe. Photolysis in the presence of both the biotinylated, benzophenone-containing probe and a farnesylated peptide competitor reduced the extent of labeling, suggesting that labeling is occurring in the active site. PMID:20619662

  16. Correlation of angiotensin I-converting enzyme gene insertion/deletion polymorphism with rheumatic heart disease: a meta-analysis

    PubMed Central

    Tian, Yulong; Ge, Zhongchun; Xing, Yuliang; Sun, Yan; Ying, Jie

    2016-01-01

    Rheumatic heart disease (RHD) is a serious cardiovascular disorder worldwide. Several articles have reported the effect of angiotensin I-converting enzyme gene insertion/deletion (ACE I/D) polymorphism in RHD risk. However, the results still remain inconsistent. The objective of the present study was to assess more precise estimations of the relationship between ACE I/D variant and RHD susceptibility. Relevant case–control studies published between January 2000 and 2016 were searched in the electronic databases. The odds ratio (OR) with its 95% confidence interval (CI) was employed to calculate the strength of the effect. A total of nine articles were retrieved, including 1333 RHD patients and 1212 healthy controls. Overall, our result did not detect a significant association between ACE I/D polymorphism and RHD risk under each genetic model (P > 0.05). Subgroup analysis by ethnicity showed no positive relationship in Asians as well (P > 0.05). With respect to the severity of RHD, our result found that the frequency differences between mitral valve lesion (MVL), combined valve lesion (CVL) and healthy controls were not significantly different. Furthermore, no significant association was found between female, male RHD patients and the controls regarding to the ACE I/D polymorphism. In conclusion, our result indicated that ACE I/D polymorphism might not be a risk factor for RHD progression based on the existing research results. Additional well-designed studies with larger samples are still needed to confirm these findings. PMID:27758878

  17. Cardiovascular risk reduction in hypertension: angiotensin-converting enzyme inhibitors, angiotensin receptor blockers. Where are we up to?

    PubMed

    Sindone, A; Erlich, J; Lee, C; Newman, H; Suranyi, M; Roger, S D

    2016-03-01

    Previously, management of hypertension has concentrated on lowering elevated blood pressure. However, the target has shifted to reducing absolute cardiovascular (CV) risk. It is estimated that two in three Australian adults have three or more CV risk factors at the same time. Moderate reductions in several risk factors can, therefore, be more effective than major reductions in one. When managing hypertension, therapy should be focused on medications with the strongest evidence for CV event reduction, substituting alternatives only when a primary choice is not appropriate. Hypertension management guidelines categorise angiotensin-converting enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARB) interchangeably as first-line treatments in uncomplicated hypertension. These medications have different mechanisms of action and quite different evidence bases. They are not interchangeable and their prescription should be based on clinical evidence. Despite this, currently ARB prescriptions are increasing at a higher rate than those for ACEI and other antihypertensive classes. Evidence that ACEI therapy prevents CV events and death, in patients with coronary artery disease or multiple CV risk factors, emerged from the European trial on reduction of cardiac events with perindopril in stable coronary artery disease (EUROPA) and Heart Outcomes Prevention Evaluation (HOPE) trials respectively. The consistent benefit has been demonstrated in meta-analyses. The clinical trial data for ARB are less consistent, particularly regarding CV outcomes and mortality benefit. The evidence supports the use of ACEI (Class 1a) compared with ARB despite current prescribing trends.

  18. Interaction of severe acute respiratory syndrome-coronavirus and NL63 coronavirus spike proteins with angiotensin converting enzyme-2.

    PubMed

    Mathewson, Alison C; Bishop, Alexandra; Yao, Yongxiu; Kemp, Fred; Ren, Junyuan; Chen, Hongying; Xu, Xiaodong; Berkhout, Ben; van der Hoek, Lia; Jones, Ian M

    2008-11-01

    Although in different groups, the coronaviruses severe acute respiratory syndrome-coronavirus (SARS-CoV) and NL63 use the same receptor, angiotensin converting enzyme (ACE)-2, for entry into the host cell. Despite this common receptor, the consequence of entry is very different; severe respiratory distress in the case of SARS-CoV but frequently only a mild respiratory infection for NL63. Using a wholly recombinant system, we have investigated the ability of each virus receptor-binding protein, spike or S protein, to bind to ACE-2 in solution and on the cell surface. In both assays, we find that the NL63 S protein has a weaker interaction with ACE-2 than the SARS-CoV S protein, particularly in solution binding, but the residues required for contact are similar. We also confirm that the ACE-2-binding site of NL63 S lies between residues 190 and 739. A lower-affinity interaction with ACE-2 might partly explain the different pathological consequences of infection by SARS-CoV and NL63.

  19. Replication-dependent downregulation of cellular angiotensin-converting enzyme 2 protein expression by human coronavirus NL63.

    PubMed

    Dijkman, Ronald; Jebbink, Maarten F; Deijs, Martin; Milewska, Aleksandra; Pyrc, Krzysztof; Buelow, Elena; van der Bijl, Anna; van der Hoek, Lia

    2012-09-01

    Like severe acute respiratory syndrome coronavirus (SARS-CoV), human coronavirus (HCoV)-NL63 employs angiotensin-converting enzyme 2 (ACE2) as a receptor for cellular entry. SARS-CoV infection causes robust downregulation of cellular ACE2 expression levels and it has been suggested that the SARS-CoV effect on ACE2 is involved in the severity of disease. We investigated whether cellular ACE2 downregulation occurs at optimal replication conditions of HCoV-NL63 infection. The expression of the homologue of ACE2, the ACE protein not used as a receptor by HCoV-NL63, was measured as a control. A specific decrease for ACE2 protein level was observed when HCoV-NL63 was cultured at 34 °C. Culturing the virus at the suboptimal temperature of 37 °C resulted in low replication of the virus and the effect on ACE2 expression was lost. We conclude that the decline of ACE2 expression is dependent on the efficiency of HCoV-NL63 replication, and that HCoV-NL63 and SARS-CoV both affect cellular ACE2 expression during infection.

  20. Angiotensin-converting enzyme inhibitory activity and antioxidant properties of Nepeta crassifolia Boiss & Buhse and Nepeta binaludensis Jamzad.

    PubMed

    Tundis, Rosa; Nadjafi, Farsad; Menichini, Francesco

    2013-04-01

    This article reports phytochemical and biological studies on Nepeta binaludensis and Nepeta crassifolia. Both species were investigated for their angiotensin-converting enzyme (ACE) inhibitory activity and antioxidant properties through three in vitro models [2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and ferric reducing antioxidant power (FRAP) assay]. Aerial parts were extracted with methanol and partitioned between water and subsequently n-hexane, ethyl acetate and n-butanol. N. binaludensis methanol extract exerted significantly higher reducing power (1.9 μM Fe(II)/g) than did the positive control butylhydroxytoluene (63.2 μM Fe(II)/g) in FRAP assay. The highest DPPH radical scavenging activity was found for N. crassifolia, with IC50 values of 9.6 and 12.1 µg/mL for ethyl acetate and n-butanol fractions, respectively. n-Butanol fraction of both species showed the highest ACE inhibitory activity, with IC50 values of 59.3 and 81.7 µg/mL for N. binaludensis and N. crassifolia, respectively. Phytochemical investigations resulted in the isolation of ursolic acid, oleanolic acid, apigenin, luteolin and ixoroside. Apigenin-7-O-glucoside, 8-hydroxycirsimaritin and cirsimaritin were furthermore identified in N. crassifolia ethyl acetate-soluble fraction. Nepetanudoside B was isolated from the n-butanol fraction of N. binaludensis.

  1. A Tricholoma matsutake Peptide with Angiotensin Converting Enzyme Inhibitory and Antioxidative Activities and Antihypertensive Effects in Spontaneously Hypertensive Rats

    PubMed Central

    Geng, Xueran; Tian, Guoting; Zhang, Weiwei; Zhao, Yongchang; Zhao, Liyan; Wang, Hexiang; Ng, Tzi Bun

    2016-01-01

    Hypertension is a major risk factor for cardiovascular disease. A crude water extract of the fruiting bodies of a highly prized mushroom Tricholoma matsutakei exerted an antihypertensive action on spontaneously hypertensive rats (SHRs) at a dosage of 400 mg/kg. An angiotensin converting enzyme (ACE) inhibitory peptide with an IC50 of 0.40 μM was purified from the extract and designated as TMP. Its amino acid sequence was elucidated to be WALKGYK through LC-MS/MS analysis. The Lineweaver-Burk plot suggested that TMP was a non-competitive inhibitor of ACE. A short-term assay of antihypertensive activity demonstrated that TMP at the dosage of 25 mg/kg could significantly lower the systolic blood pressure (SBP) of SHRs. TMP exhibited remarkable stability over a wide range of temperatures and pH values. It also demonstrated 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. The aforementioned activities of TMP were corroborated by utilizing the synthetic peptide. Hence T. matsutake can be used as a functional food to help prevent hypertension- associated diseases. PMID:27052674

  2. A Tricholoma matsutake Peptide with Angiotensin Converting Enzyme Inhibitory and Antioxidative Activities and Antihypertensive Effects in Spontaneously Hypertensive Rats.

    PubMed

    Geng, Xueran; Tian, Guoting; Zhang, Weiwei; Zhao, Yongchang; Zhao, Liyan; Wang, Hexiang; Ng, Tzi Bun

    2016-04-07

    Hypertension is a major risk factor for cardiovascular disease. A crude water extract of the fruiting bodies of a highly prized mushroom Tricholoma matsutakei exerted an antihypertensive action on spontaneously hypertensive rats (SHRs) at a dosage of 400 mg/kg. An angiotensin converting enzyme (ACE) inhibitory peptide with an IC50 of 0.40 μM was purified from the extract and designated as TMP. Its amino acid sequence was elucidated to be WALKGYK through LC-MS/MS analysis. The Lineweaver-Burk plot suggested that TMP was a non-competitive inhibitor of ACE. A short-term assay of antihypertensive activity demonstrated that TMP at the dosage of 25 mg/kg could significantly lower the systolic blood pressure (SBP) of SHRs. TMP exhibited remarkable stability over a wide range of temperatures and pH values. It also demonstrated 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity. The aforementioned activities of TMP were corroborated by utilizing the synthetic peptide. Hence T. matsutake can be used as a functional food to help prevent hypertension- associated diseases.

  3. The effectiveness and safety of angiotensin-converting enzyme inhibition or receptor blockade in vascular diseases in patients with hemodialysis

    PubMed Central

    Liao, Kuang-Ming; Cheng, Hui-Teng; Lee, Yi-Hsuan; Chen, Chung-Yu

    2017-01-01

    Abstract Patients with end-stage renal disease (ESRD) who are on hemodialysis have high risk of vascular diseases. Our study sought to examine whether angiotensin-converting enzyme inhibitors (ACEIs) or angiotensin type 1 receptor blockers (ARBs) could reduce the frequencies of cardiovascular and cerebrovascular events in patients receiving hemodialysis using the medication possession ratio (MPR) method of analysis. This retrospective cohort study identified cases of ESRD with dialysis from the National Health Insurance Research Database between 1999 and 2006, and used Cox-regression methods to evaluate risk of poor outcomes. Primary outcomes, including death from any cause, and secondary outcomes, including admission for stroke, myocardial infarction, and heart failure, were examined. Compared to the nonuser group, the adjusted HRs for mortality of the nonadherence group and the adherence group were 0.81 (95% CI: 0.76–0.86) and 0.98 (95% CI: 0.86–1.13), respectively. Cardiovascular events were more frequent in patients with ESRD receiving ACEIs /ARBs than in nonusers. Compared with nonusers, the hazard of secondary outcome significantly increased in the nonadherence group or adherence group in 10 years follow-up. Compared with patients with diabetes or chronic kidney disease, patients on hemodialysis may not experience the same cardiovascular and cerebrovascular benefits from ACEIs/ARBs use. PMID:28353612

  4. Interaction of severe acute respiratory syndrome-coronavirus and NL63 coronavirus spike proteins with angiotensin converting enzyme-2

    PubMed Central

    Mathewson, Alison C.; Bishop, Alexandra; Yao, Yongxiu; Kemp, Fred; Ren, Junyuan; Chen, Hongying; Xu, Xiaodong; Berkhout, Ben; van der Hoek, Lia; Jones, Ian M.

    2008-01-01

    Although in different groups, the coronaviruses severe acute respiratory syndrome-coronavirus (SARS-CoV) and NL63 use the same receptor, angiotensin converting enzyme (ACE)-2, for entry into the host cell. Despite this common receptor, the consequence of entry is very different; severe respiratory distress in the case of SARS-CoV but frequently only a mild respiratory infection for NL63. Using a wholly recombinant system, we have investigated the ability of each virus receptor-binding protein, spike or S protein, to bind to ACE-2 in solution and on the cell surface. In both assays, we find that the NL63 S protein has a weaker interaction with ACE-2 than the SARS-CoV S protein, particularly in solution binding, but the residues required for contact are similar. We also confirm that the ACE-2-binding site of NL63 S lies between residues 190 and 739. A lower-affinity interaction with ACE-2 might partly explain the different pathological consequences of infection by SARS-CoV and NL63. PMID:18931070

  5. Protein Kinase C-δ Mediates Shedding of Angiotensin-Converting Enzyme 2 from Proximal Tubular Cells

    PubMed Central

    Xiao, Fengxia; Zimpelmann, Joseph; Burger, Dylan; Kennedy, Christopher; Hébert, Richard L.; Burns, Kevin D.

    2016-01-01

    Angiotensin-converting enzyme 2 (ACE2) degrades angiotensin (Ang) II to Ang-(1–7), and protects against diabetic renal injury. Soluble ACE2 fragments are shed from the proximal tubule, and appear at high levels in the urine with diabetes. High glucose-induced shedding of ACE2 from proximal tubular cells is mediated by the enzyme “a disintegrin and metalloproteinase-17″ (ADAM17). Here, we investigated the mechanism for constitutive shedding of ACE2. Mouse proximal tubular cells were cultured and ACE2 shedding into the media was assessed by enzyme activity assay and immunoblot analysis. Cells were incubated with pharmacologic inhibitors, or transfected with silencing (si) RNA. Incubation of proximal tubular cells with increasing concentrations of D-glucose stimulated ACE2 shedding, which peaked at 16 mM, while L-glucose (osmotic control) had no effect on shedding. In cells maintained in 7.8 mM D-glucose, ACE2 shedding was significantly inhibited by the pan-protein kinase C (PKC) competitive inhibitor sotrastaurin, but not by an inhibitor of ADAM17. Incubation of cells with the PKC-α and -β1-specific inhibitor Go6976, the PKC β1 and β2-specific inhibitor ruboxistaurin, inhibitors of matrix metalloproteinases-2,-8, and -9, or an inhibitor of ADAM10 (GI250423X) had no effect on basal ACE2 shedding. By contrast, the PKC-δ inhibitor rottlerin significantly inhibited both constitutive and high glucose-induced ACE2 shedding. Transfection of cells with siRNA directed against PKC-δ reduced ACE2 shedding by 20%, while knockdown of PKC-ε was without effect. These results indicate that constitutive shedding of ACE2 from proximal tubular cells is mediated by PKC-δ, which is also linked to high glucose-induced shedding. Targeting PKC-δ may preserve membrane-bound ACE2 in proximal tubule in disease states and diminish Ang II-stimulated adverse signaling. PMID:27313531

  6. Increasing brain angiotensin converting enzyme 2 activity decreases anxiety-like behavior in male mice by activating central Mas receptors.

    PubMed

    Wang, Lei; de Kloet, Annette D; Pati, Dipanwita; Hiller, Helmut; Smith, Justin A; Pioquinto, David J; Ludin, Jacob A; Oh, S Paul; Katovich, Michael J; Frazier, Charles J; Raizada, Mohan K; Krause, Eric G

    2016-06-01

    Over-activation of the brain renin-angiotensin system (RAS) has been implicated in the etiology of anxiety disorders. Angiotensin converting enzyme 2 (ACE2) inhibits RAS activity by converting angiotensin-II, the effector peptide of RAS, to angiotensin-(1-7), which activates the Mas receptor (MasR). Whether increasing brain ACE2 activity reduces anxiety by stimulating central MasR is unknown. To test the hypothesis that increasing brain ACE2 activity reduces anxiety-like behavior via central MasR stimulation, we generated male mice overexpressing ACE2 (ACE2 KI mice) and wild type littermate controls (WT). ACE2 KI mice explored the open arms of the elevated plus maze (EPM) significantly more than WT, suggesting increasing ACE2 activity is anxiolytic. Central delivery of diminazene aceturate, an ACE2 activator, to C57BL/6 mice also reduced anxiety-like behavior in the EPM, but centrally administering ACE2 KI mice A-779, a MasR antagonist, abolished their anxiolytic phenotype, suggesting that ACE2 reduces anxiety-like behavior by activating central MasR. To identify the brain circuits mediating these effects, we measured Fos, a marker of neuronal activation, subsequent to EPM exposure and found that ACE2 KI mice had decreased Fos in the bed nucleus of stria terminalis but had increased Fos in the basolateral amygdala (BLA). Within the BLA, we determined that ∼62% of GABAergic neurons contained MasR mRNA and expression of MasR mRNA was upregulated by ACE2 overexpression, suggesting that ACE2 may influence GABA neurotransmission within the BLA via MasR activation. Indeed, ACE2 overexpression was associated with increased frequency of spontaneous inhibitory postsynaptic currents (indicative of presynaptic release of GABA) onto BLA pyramidal neurons and central infusion of A-779 eliminated this effect. Collectively, these results suggest that ACE2 may reduce anxiety-like behavior by activating central MasR that facilitate GABA release onto pyramidal neurons within the

  7. Casein Fermentate of Lactobacillus animalis DPC6134 Contains a Range of Novel Propeptide Angiotensin-Converting Enzyme Inhibitors▿

    PubMed Central

    Hayes, M.; Stanton, C.; Slattery, H.; O'Sullivan, O.; Hill, C.; Fitzgerald, G. F.; Ross, R. P.

    2007-01-01

    This work evaluated the angiotensin-converting-enzyme (ACE)-inhibitory activities of a bovine sodium caseinate fermentate generated using the proteolytic capabilities of the porcine small intestinal isolate Lactobacillus animalis DPC6134 (NCIMB deposit 41355). The crude 10-kDa L. animalis DPC6134 fermentate exhibited ACE-inhibitory activity of 85.51% (±15%) and had a 50% inhibitory concentration (IC50) of 0.8 mg protein/ml compared to captopril, which had an IC50 value of 0.005 mg/ml. Fractionation of the crude L. animalis DPC6134 fermentate by membrane filtration and reversed-phase high-performance liquid chromatography (HPLC) generated three bioactive fractions from a total of 72 fractions. Fractions 10, 19, and 43 displayed ACE-inhibitory activity percentages of 67.53 (±15), 83.71 (±19), and 42.36 (±11), respectively, where ACE inhibition was determined with 80 μl of the fractions with protein concentrations of 0.5 mg/ml. HPLC and mass spectrometry analysis identified 25 distinct peptide sequences derived from α-, β-, and κ-caseins. In silico predictions, based on the C-terminal tetrapeptide sequences, suggested that peptide NIPPLTQTPVVVPPFIQ, corresponding to β-casein f(73-89); peptide IGSENSEKTTMP, corresponding to αs1-casein f(201212); peptide SQSKVLPVPQ, corresponding to β-casein f(166-175); peptide MPFPKYPVEP, corresponding to β-casein f(124133); and peptide EPVLGPVRGPFP, corresponding to β-casein f(210-221), contained ACE-inhibitory activities. These peptides were chosen for chemical synthesis to confirm the ACE-inhibitory activity of the fractions. Chemically synthesized peptides displayed IC50 values in the range of 92 μM to 790 μM. Additionally, a simulated gastrointestinal digestion confirmed that the ACE-inhibitory 10-kDa L. animalis DPC6134 fermentation was resistant to a cocktail of digestive enzymes found in the gastrointestinal tract. PMID:17483275

  8. Structural determinants for binding to angiotensin converting enzyme 2 (ACE2) and angiotensin receptors 1 and 2

    PubMed Central

    Clayton, Daniel; Hanchapola, Iresha; Thomas, Walter G.; Widdop, Robert E.; Smith, Alexander I.; Perlmutter, Patrick; Aguilar, Marie-Isabel

    2015-01-01

    Angiotensin converting enzyme 2 (ACE2) is a zinc carboxypeptidase involved in the renin–angiotensin system (RAS) and inactivates the potent vasopressive peptide angiotensin II (Ang II) by removing the C-terminal phenylalanine residue to yield Ang1–7. This conversion inactivates the vasoconstrictive action of Ang II and yields a peptide that acts as a vasodilatory molecule at the Mas receptor and potentially other receptors. Given the growing complexity of RAS and level of cross-talk between ligands and their corresponding enzymes and receptors, the design of molecules with selectivity for the major RAS binding partners to control cardiovascular tone is an on-going challenge. In previous studies we used single β-amino acid substitutions to modulate the structure of Ang II and its selectivity for ACE2, AT1R, and angiotensin type 2 (AT2R) receptor. We showed that modification at the C-terminus of Ang II generally resulted in more pronounced changes to secondary structure and ligand binding, and here, we further explore this region for the potential to modulate ligand specificity. In this study, (1) a library of 47 peptides derived from the C-terminal tetrapeptide sequence (-IHPF) of Ang II was synthesized and assessed for ACE2 binding, (2) the terminal group requirements for high affinity ACE2 binding were explored by and N- and C-terminal modification, (3) high affinity ACE2 binding chimeric AngII analogs were then synthesized and assessed, (4) the structure of the full-length Ang II analogs were assessed by circular dichroism, and (5) the Ang II analogs were assessed for AT1R/AT2R selectivity by cell-based assays. Studies on the C-terminus of Ang II demonstrated varied specificity at different residue positions for ACE2 binding and four Ang II chimeric peptides were identified as selective ligands for the AT2 receptor. Overall, these results provide insight into the residue and structural requirements for ACE2 binding and angiotensin receptor selectivity. PMID

  9. Soluble and Catalytically Active Endothelin Converting Enzyme-1 is Present in Cerebrospinal Fluid of Subarachnoid Hemorrhage Patients

    PubMed Central

    Kuruppu, Sanjaya; Chou, Sherry H.-Y.; Feske, Steven K.; Suh, Sarah; Hanchapola, Iresha; Lo, Eng H.; Ning, MingMing; Smith, A. Ian

    2014-01-01

    Endothelin converting Enzyme-1 (ECE-1) is essential for the production of Endothelin-1 (ET-1), which is associated with vasospasm following subarachnoid hemorrhage (SAH). We have previously demonstrated the presence of a catalytically active soluble form of ECE-1 in the media of endothelial cells. We aimed to determine if this form of ECE-1 exists in vivo, in cerebrospinal fluid (CSF) of SAH patients. We examined CSF taken from SAH subjects for the presence of soluble ECE-1 using a bradykinin based quenched fluorescent substrate assay. We obtained further confirmation by characterizing the CSF mediated cleavage products of BigET-1 and BigET18–34 (6 μg/ml) using mass spectrometry. The specificity of cleavage was confirmed using the ECE-1 inhibitor CGS35066 5nmol/L. SAH CSF samples had mean ECE-1 activity of 0.127 ± 0.037 μmols of substrate cleaved/μl of CSF/24 h. The C-terminal peptides generated upon the cleavage of BigET-1 and BigET18–34 were detected 48 h after incubation of these substrates with CSF. Cleavage of these substrates was inhibited by CGS35066. Results of Western blots also produced strong evidence for the presence of truncated soluble ECE-1 in CSF. These results strongly suggest the presence of a truncated but catalytically active form of ECE-1 in the CSF of SAH subjects. Further studies are necessary to determine the biological significance of soluble ECE-1 in CSF of SAH subjects, including an association with vasospasm after SAH. PMID:23816989

  10. Association of exercise training and angiotensin-converting enzyme 2 activator improves baroreflex sensitivity of spontaneously hypertensive rats

    PubMed Central

    Lopes, P.R.; Moreira, M.C.S.; Marques, S.M.; Pinto, I.S.J.; Macedo, L.M.; Silva, C.C.; Freiria-Oliveira, A.H.; Rebelo, A.C.S.; Reis, A.A.S.; Rosa, D.A.; Ferreira-Neto, M.L.; Castro, C.H.; Pedrino, G.R.

    2016-01-01

    The present study sought to determine cardiovascular effects of aerobic training associated with diminazene aceturate (DIZE), an activator of the angiotensin converting enzyme 2, in spontaneously hypertensive rats (SHRs). Male SHRs (280–350 g) were either subjected to exercise training or not (sedentary group). The trained group was subjected to 8 weeks of aerobic training on a treadmill (five times a week, lasting 60 min at an intensity of 50–60% of maximum aerobic speed). In the last 15 days of the experimental protocol, these groups were redistributed into four groups: i) sedentary SHRs with daily treatment of 1 mg/kg DIZE (S+D1); ii) trained SHRs with daily treatment of 1 mg/kg DIZE (T+D1); iii) sedentary SHRs with daily treatment of vehicle (S+V); and iv) trained SHRs with daily treatment of vehicle (T+V). After treatment, SHRs were anesthetized and subjected to artery and femoral vein cannulation prior to the implantation of ECG electrode. After 24 h, mean arterial pressure (MAP) and heart rate (HR) were recorded; the baroreflex sensitivity and the effect of double autonomic blockade (DAB) were evaluated in non-anesthetized SHRs. DIZE treatment improved baroreflex sensitivity in the T+D1 group as compared with the T+V and S+D1 groups. The intrinsic heart rate (IHR) and MAP were reduced in T+D1 group as compared with T+V and S+D1 groups. Hence, we conclude that the association of exercise training with DIZE treatment improved baroreflex function and cardiovascular regulation. PMID:27533767

  11. Angiotensin-converting enzyme 2 amplification limited to the circulation does not protect mice from development of diabetic nephropathy.

    PubMed

    Wysocki, Jan; Ye, Minghao; Khattab, Ahmed M; Fogo, Agnes; Martin, Aline; David, Nicolae Valentin; Kanwar, Yashpal; Osborn, Mark; Batlle, Daniel

    2016-12-04

    Blockers of the renin-angiotensin system are effective in the treatment of experimental and clinical diabetic nephropathy. An approach different from blocking the formation or action of angiotensin II (1-8) that could also be effective involves fostering its degradation. Angiotensin-converting enzyme 2 (ACE2) is a monocarboxypeptidase that cleaves angiotensin II (1-8) to form angiotensin (1-7). Therefore, we examined the renal effects of murine recombinant ACE2 in mice with streptozotocin-induced diabetic nephropathy as well as that of amplification of circulating ACE2 using minicircle DNA delivery prior to induction of experimental diabetes. This delivery resulted in a long-term sustained and profound increase in serum ACE2 activity and enhanced ability to metabolize an acute angiotensin II (1-8) load. In mice with streptozotocin-induced diabetes pretreated with minicircle ACE2, ACE2 protein in plasma increased markedly and this was associated with a more than 100-fold increase in serum ACE2 activity. However, minicircle ACE2 did not result in changes in urinary ACE2 activity as compared to untreated diabetic mice. In both diabetic groups, glomerular filtration rate increased significantly and to the same extent as compared to non-diabetic controls. Albuminuria, glomerular mesangial expansion, glomerular cellularity, and glomerular size were all increased to a similar extent in minicircle ACE2-treated and untreated diabetic mice, as compared to non-diabetic controls. Recombinant mouse ACE2 given for 4 weeks by intraperitoneal daily injections in mice with streptozotocin-induced diabetic nephropathy also failed to improve albuminuria or kidney pathology. Thus, a profound augmentation of ACE2 confined to the circulation failed to ameliorate the glomerular lesions and hyperfiltration characteristic of early diabetic nephropathy. These findings emphasize the importance of targeting the kidney rather than the circulatory renin angiotensin system to combat diabetic

  12. Angiotensin-converting enzyme and progression of white matter lesions and brain atrophy--the SMART-MR study.

    PubMed

    Jochemsen, Hadassa M; Geerlings, Mirjam I; Grool, Anne M; Vincken, Koen L; Mali, Willem Ptm; van der Graaf, Yolanda; Muller, Majon

    2012-01-01

    High levels of angiotensin-converting-enzyme (ACE) may increase the risk of dementia through blood pressure elevation and subsequent development of cerebral small-vessel disease. However, high ACE levels may also decrease this risk through amyloid degradation which prevents brain atrophy. Within the SMART-MR study, a prospective cohort study among patients with symptomatic atherosclerotic disease, serum ACE levels were measured at baseline and a 1.5 Tesla brain MRI was performed at baseline and after on average (range) 3.9 (3.0-5.8) years of follow-up in 682 persons (mean age 58 ± 10 years). Brain segmentation was used to quantify total, deep, and periventricular white matter lesion (WML) volume, and total brain, cortical gray matter and ventricular volume (%ICV). Lacunar infarcts were rated visually. Regression analyses were used to examine the prospective associations between serum ACE and brain measures. Patients with the highest serum ACE levels (>43.3 U/L) had borderline significantly more progression of deep WML volumes than patients with the lowest ACE levels (<21.8 U/L); mean difference (95% CI) in change was 0.20 (-0.02; 0.43) %ICV. On the contrary, patients with the highest serum ACE levels had significantly less progression of cortical brain atrophy than patients with the lowest ACE levels; mean difference (95% CI) in change was 0.78 (0.21; 1.36) %ICV. Serum ACE was not associated with subcortical atrophy, periventricular WML, or lacunar infarcts. Our results show that higher ACE activity is associated with somewhat more progression of deep WML volume, but with less progression of cortical brain atrophy. This suggests both detrimental and beneficial effects of high ACE levels on the brain.

  13. Involvement of TNF-α converting enzyme in the development of psoriasis-like lesions in a mouse model.

    PubMed

    Sato, Kenji; Takaishi, Mikiro; Tokuoka, Shota; Sano, Shigetoshi

    2014-01-01

    TNF-α plays a crucial role in psoriasis; therefore, TNF inhibition has become a gold standard for the treatment of psoriasis. TNF-α is processed from a membrane-bound form by TNF-α converting enzyme (TACE) to soluble form, which exerts a number of biological activities. EGF receptor (EGFR) ligands, including heparin-binding EGF-like growth factor (HB-EGF), amphiregulin and transforming growth factor (TGF)-α are also TACE substrates and are psoriasis-associated growth factors. Vascular endothelial growth factor (VEGF), one of the downstream molecules of EGFR and TNF signaling, plays a key role in angiogenesis for developing psoriasis. In the present study, to assess the possible role of TACE in the pathogenesis of psoriasis, we investigated the involvement of TACE in TPA-induced psoriasis-like lesions in K5.Stat3C mice, which represent a mouse model of psoriasis. In this mouse model, TNF-α, amphiregulin, HB-EGF and TGF-α were significantly up-regulated in the skin lesions, similar to human psoriasis. Treatment of K5.Stat3C mice with TNF-α or EGFR inhibitors attenuated the skin lesions, suggesting the roles of TACE substrates in psoriasis. Furthermore, the skin lesions of K5.Stat3C mice showed down-regulation of tissue inhibitor of metalloproteinase-3, an endogenous inhibitor of TACE, and an increase in soluble TNF-α. A TACE inhibitor abrogated EGFR ligand-dependent keratinocyte proliferation and VEGF production in vitro, suggesting that TACE was involved in both epidermal hyperplasia and angiogenesis during psoriasis development. These results strongly suggest that TACE contributes to the development of psoriatic lesions through releasing two kinds of psoriasis mediators, TNF-α and EGFR ligands. Therefore, TACE could be a potential therapeutic target for the treatment of psoriasis.

  14. Angiotensin-converting enzyme-2 (ACE2): comparative modeling of the active site, specificity requirements, and chloride dependence.

    PubMed

    Guy, Jodie L; Jackson, Richard M; Acharya, K Ravi; Sturrock, Edward D; Hooper, Nigel M; Turner, Anthony J

    2003-11-18

    Angiotensin-converting enzyme 2 (ACE2), a homologue of ACE, represents a new and potentially important target in cardio-renal disease. A model of the active site of ACE2, based on the crystal structure of testicular ACE, has been developed and indicates that the catalytic mechanism of ACE2 resembles that of ACE. Structural differences exist between the active site of ACE (dipeptidyl carboxypeptidase) and ACE2 (carboxypeptidase) that are responsible for the differences in specificity. The main differences occur in the ligand-binding pockets, particularly at the S2' subsite and in the binding of the peptide carboxy-terminus. The model explains why the classical ACE inhibitor lisinopril is unable to bind to ACE2. On the basis of the ability of ACE2 to cleave a variety of biologically active peptides, a consensus sequence of Pro-X-Pro-hydrophobic/basic for the protease specificity of ACE2 has been defined that is supported by the ACE2 model. The dipeptide, Pro-Phe, completely inhibits ACE2 activity at 180 microM with angiotensin II as the substrate. As with ACE, the chloride dependence of ACE2 is substrate-specific such that the hydrolysis of angiotensin I and the synthetic peptide substrate, Mca-APK(Dnp), are activated in the presence of chloride ions, whereas the cleavage of angiotensin II is inhibited. The ACE2 model is also suggestive of a possible mechanism for chloride activation. The structural insights provided by these analyses for the differences in inhibition pattern and substrate specificity among ACE and its homologue ACE2 and for the chloride dependence of ACE/ACE2 activity are valuable in understanding the function and regulation of ACE2.

  15. Endothelin-converting enzyme-1 activity, endothelin-1 production, and free radical-dependent vasoconstriction in Alzheimer's disease.

    PubMed

    Palmer, Jennifer C; Tayler, Hannah M; Love, Seth

    2013-01-01

    Alzheimer's disease (AD) patients have reduced cerebral blood flow. This precedes dementia and may contribute to its progression. In mice that overexpress amyloid-β protein precursor, cerebral blood flow declines before the development of plaques or cognitive abnormalities. In the brain, endothelin-1 (ET-1) is a locally acting vasoconstrictor, produced in neurons by endothelin-converting enzyme (ECE)-2 and in endothelial cells by ECE-1. Both ECEs are also capable of cleaving amyloid-β (Aβ). We previously showed ECE-2 and ET-1 to be elevated in postmortem temporal cortex from AD patients, and ECE-2 expression and ET-1 release to be upregulated by Aβ42 in vitro. We have now studied isolated leptomeningeal blood vessels from postmortem brains and found that although ECE-1 level is reduced, ECE-1 activity and ET-1 level are significantly elevated in AD vessels. This is specific to AD as there is no specific change in vascular dementia vessels. In primary cultures of human brain endothelial cells, both Aβ40 and Aβ42 caused a significant increase in ET-1 release, the increase being particularly pronounced with Aβ40. In view of previous studies implicating free radicals in the endothelial dysfunction caused by Aβ40, we examined whether Aβ-mediated ET-1 release could be prevented by the antioxidant superoxide dismutase. Addition of superoxide dismutase to cells exposed to Aβ40 prevented the increase in the concentration of ET-1. Our findings indicate that cerebral vasoconstriction induced by Aβ results in part from a free radical-mediated increase in ECE-1 activity and ET-1 production.

  16. New Perspectives in the Renin-Angiotensin-Aldosterone System (RAAS) II: Albumin Suppresses Angiotensin Converting Enzyme (ACE) Activity in Human

    PubMed Central

    Fagyas, Miklós; Úri, Katalin; Siket, Ivetta M.; Fülöp, Gábor Á.; Csató, Viktória; Daragó, Andrea; Boczán, Judit; Bányai, Emese; Szentkirályi, István Elek; Maros, Tamás Miklós; Szerafin, Tamás; Édes, István; Papp, Zoltán; Tóth, Attila

    2014-01-01

    About 8% of the adult population is taking angiotensin-converting enzyme (ACE) inhibitors to treat cardiovascular disease including hypertension, myocardial infarction and heart failure. These drugs decrease mortality by up to one-fifth in these patients. We and others have reported previously that endogenous inhibitory substances suppress serum ACE activity, in vivo, similarly to the ACE inhibitor drugs. Here we have made an effort to identify this endogenous ACE inhibitor substance. ACE was crosslinked with interacting proteins in human sera. The crosslinked products were immunoprecipitated and subjected to Western blot. One of the crosslinked products was recognized by both anti-ACE and anti-HSA (human serum albumin) antibodies. Direct ACE-HSA interaction was confirmed by binding assays using purified ACE and HSA. HSA inhibited human purified (circulating) and human recombinant ACE with potencies (IC50) of 5.7±0.7 and 9.5±1.1 mg/mL, respectively. Effects of HSA on the tissue bound native ACE were tested on human saphenous vein samples. Angiotensin I evoked vasoconstriction was inhibited by HSA in this vascular tissue (maximal force with HSA: 6.14±1.34 mN, without HSA: 13.54±2.63 mN), while HSA was without effects on angiotensin II mediated constrictions (maximal force with HSA: 18.73±2.17 mN, without HSA: 19.22±3.50 mN). The main finding of this study is that HSA was identified as a potent physiological inhibitor of the ACE. The enzymatic activity of ACE appears to be almost completely suppressed by HSA when it is present in its physiological concentration. These data suggest that angiotensin I conversion is limited by low physiological ACE activities, in vivo. PMID:24691203

  17. Ocular Inserts for Sustained Release of the Angiotensin-Converting Enzyme 2 Activator, Diminazene Aceturate, to Treat Glaucoma in Rats.

    PubMed

    Foureaux, Giselle; Franca, Juçara Ribeiro; Nogueira, José Carlos; Fulgêncio, Gustavo de Oliveira; Ribeiro, Tatiana Gomes; Castilho, Rachel Oliveira; Yoshida, Maria Irene; Fuscaldi, Leonardo Lima; Fernandes, Simone Odília Antunes; Cardoso, Valbert Nascimento; Cronemberger, Sebastião; Faraco, André Augusto Gomes; Ferreira, Anderson José

    2015-01-01

    The aim of this study was to develop and evaluate the effects of chitosan inserts for sustained release of the angiotensin-converting enzyme 2 (ACE2) activator, diminazene aceturate (DIZE), in experimental glaucoma. Monolayer DIZE loaded inserts (D+I) were prepared and characterized through swelling, attenuated total reflectance Fourier transformed infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC) and in vitro drug release. Functionally, the effects of D+I were tested in glaucomatous rats. Glaucoma was induced by weekly injections of hyaluronic acid (HA) into the anterior chamber and intraocular pressure (IOP) measurements were performed. Retinal ganglion cells (RGC) and optic nerve head cupping were evaluated in histological sections. Biodistribution of the drug was accessed by scintigraphic images and ex vivo radiation counting. We found that DIZE increased the swelling index of the inserts. Also, it was molecularly dispersed and interspersed in the polymeric matrix as a freebase. DIZE did not lose its chemical integrity and activity when loaded in the inserts. The functional evaluation demonstrated that D+I decreased the IOP and maintained the IOP lowered for up to one month (last week: 11.0 ± 0.7 mmHg). This effect of D+I prevented the loss of RGC and degeneration of the optic nerve. No toxic effects in the eyes related to application of the inserts were observed. Moreover, biodistribution studies showed that D+I prolonged the retention of DIZE in the corneal site. We concluded that D+I provided sustained DIZE delivery in vivo, thereby evidencing the potential application of polymeric-based DIZE inserts for glaucoma management.

  18. Furosemide- sup 131 I-hippuran renography after angiotensin-converting enzyme inhibition for the diagnosis of renovascular hypertension

    SciTech Connect

    Erbsloeh-Moeller, B.Du.; Dumas, A.; Roth, D.; Sfakianakis, G.N.; Bourgoignie, J.J. )

    1991-01-01

    We have previously demonstrated the greater sensitivity of 131I-hippuran renography than 99mTC-DTPA scintigraphy to diagnose renovascular hypertension (RVH). This study assesses the predictive diagnostic value of furosemide-131I-hippuran renography after angiotensin-converting enzyme (ACE) inhibition in patients with and without RVH. All patients were investigated at the University of Miami/Jackson Memorial Medical Center. Twenty-eight patients had RVH and 22 did not. Twenty-eight patients had normal or minimally decreased renal function and 22 had renal insufficiency. Renography was performed 60 minutes after oral administration of 50 mg captopril or 10 minutes after intravenous injection of 40 micrograms/kg enalaprilat. Forty milligrams of furosemide were administered intravenously 2 minutes after injection of 131I-hippuran. The residual cortical activity (RCA) of 131I-hippuran was measured at 20 minutes. RVH was unlikely when RCA after ACE inhibition was less than 30% of peak cortical activity. Conversely, RVH was present when 131I-hippuran cortical activity steadily increased throughout the test to reach 100% at 20 minutes. In azotemic patients with RCA between 31% and 100%, RVH was differentiated from intrinsic renal disease by obtaining a baseline renogram without ACE inhibition and comparing RCA in that study and RCA after ACE inhibition. If RCA increased (indicating worsening renal function) after ACE inhibition, RVH was likely; whereas, intrinsic renal disease was more likely if RCA remained unchanged or decreased (indicating improved renal function) with ACE inhibition. The test had a specificity of 95% and a sensitivity of 96% in this population. There was a direct correlation between the results of angioplasty or surgery on high blood pressure and the changes in RCA before and after intervention (n = 20).

  19. Angiotensin-converting enzyme inhibitors reduce oxidative stress intensity in hyperglicemic conditions in rats independently from bradykinin receptor inhibitors

    PubMed Central

    Mikrut, Kinga; Kupsz, Justyna; Koźlik, Jacek; Krauss, Hanna; Pruszyńska-Oszmałek, Ewa; Gibas-Dorna, Magdalena

    2016-01-01

    Aim To investigate whether bradykinin-independent antioxidative effects of angiotensin-converting enzyme inhibitors (ACEIs) exist in acute hyperglycemia. Methods Male Wistar rats were divided into the normoglycemic group (n = 40) and the hyperglycemic group (n = 40). Hyperglycemia was induced by a single intraperitoneal injection of streptozotocin (STZ, 65 mg/kg body weight) dissolved in 0.1 mol/L citrate buffer (pH 4.5) 72 hours before sacrifice. The normoglycemic group received the same volume of citrate buffer. Each group was divided into five subgroups (n = 8): control group, captopril group, captopril + bradykinin B1 and B2 receptor antagonists group, enalapril group, and enalapril + bradykinin B1 and B2 receptor antagonists group. Captopril, enalapril, B1 and B2 receptor antagonists, or 0.15 mol/L NaCl were given at 2 and 1 hour before sacrifice. Oxidative status was determined by measuring the concentration of malondialdehyde and H2O2, and the activity of superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx). Results In STZ-induced hyperglycemic rats ACEIs significantly reduced H2O2 and MDA concentration, while they significantly enhanced SOD and GPx activity. The hyperglycemic group treated simultaneously with ACEIs and bradykinin B1 and B2 receptor antagonists showed a significant decrease in H2O2 concentration compared to the control hyperglycemic group. Conclusion These results suggest the existence of additional antioxidative effect of ACEIs in hyperglycemic conditions, which is not related to the bradykinin mediation and the structure of the drug molecule. PMID:27586552

  20. Angiotensin-converting enzyme and matrix metalloproteinase inhibition with developing heart failure: comparative effects on left ventricular function and geometry

    NASA Technical Reports Server (NTRS)

    McElmurray, J. H. 3rd; Mukherjee, R.; New, R. B.; Sampson, A. C.; King, M. K.; Hendrick, J. W.; Goldberg, A.; Peterson, T. J.; Hallak, H.; Zile, M. R.; Spinale, F. G.

    1999-01-01

    The progression of congestive heart failure (CHF) is left ventricular (LV) myocardial remodeling. The matrix metalloproteinases (MMPs) contribute to tissue remodeling and therefore MMP inhibition may serve as a useful therapeutic target in CHF. Angiotensin converting enzyme (ACE) inhibition favorably affects LV myocardial remodeling in CHF. This study examined the effects of specific MMP inhibition, ACE inhibition, and combined treatment on LV systolic and diastolic function in a model of CHF. Pigs were randomly assigned to five groups: 1) rapid atrial pacing (240 beats/min) for 3 weeks (n = 8); 2) ACE inhibition (fosinopril, 2.5 mg/kg b.i.d. orally) and rapid pacing (n = 8); 3) MMP inhibition (PD166793 2 mg/kg/day p.o.) and rapid pacing (n = 8); 4) combined ACE and MMP inhibition (2.5 mg/kg b.i.d. and 2 mg/kg/day, respectively) and rapid pacing (n = 8); and 5) controls (n = 9). LV peak wall stress increased by 2-fold with rapid pacing and was reduced in all treatment groups. LV fractional shortening fell by nearly 2-fold with rapid pacing and increased in all treatment groups. The circumferential fiber shortening-systolic stress relation was reduced with rapid pacing and increased in the ACE inhibition and combination groups. LV myocardial stiffness constant was unchanged in the rapid pacing group, increased nearly 2-fold in the MMP inhibition group, and was normalized in the ACE inhibition and combination treatment groups. Increased MMP activation contributes to the LV dilation and increased wall stress with pacing CHF and a contributory downstream mechanism of ACE inhibition is an effect on MMP activity.

  1. SLCO1B1 Variants and Angiotensin Converting Enzyme Inhibitor (Enalapril)-Induced Cough: a Pharmacogenetic Study.

    PubMed

    Luo, Jian-Quan; He, Fa-Zhong; Wang, Zhen-Min; Sun, Ning-Ling; Wang, Lu-Yan; Tang, Gen-Fu; Liu, Mou-Ze; Li, Qing; Chen, Xiao-Ping; Liu, Zhao-Qian; Zhou, Hong-Hao; Zhang, Wei

    2015-11-26

    Clinical observations suggest that incidence of cough in Chinese taking angiotensin converting enzyme inhibitors is much higher than other racial groups. Cough is the most common adverse reaction of enalapril. We investigate whether SLCO1B1 genetic polymorphisms, previously reported to be important determinants of inter-individual variability in enalapril pharmacokinetics, are associated with the enalapril-induced cough. A cohort of 450 patients with essential hypertension taking 10 mg enalapril maleate were genotyped for the functional SLCO1B1 variants, 388A > G (Asn130Asp, rs2306283) and 521T > C (Val174Ala, rs4149056). The primary endpoint was cough, which was recorded when participants were bothered by cough and respiratory symptoms during enalapril treatment without an identifiable cause. SLCO1B1 521C allele conferred a 2-fold relative risk of enalapril-induced cough (95% confidence interval [CI] = 1.34-3.04, P = 6.2 × 10(-4)), and haplotype analysis suggested the relative risk of cough was 6.94-fold (95% CI = 1.30-37.07, P = 0.020) in SLCO1B1*15/*15 carriers. Furthermore, there was strong evidence for a gene-dose effect (percent with cough in those with 0, 1, or 2 copy of the 521C allele: 28.2%, 42.5%, and 71.4%, trend P = 6.6 × 10(-4)). Our study highlights, for the first time, SLCO1B1 variants are strongly associated with an increased risk of enalapril-induced cough. The findings will be useful to provide pharmacogenetic markers for enalapril treatment.

  2. Molybdenum(VI) salts convert the xanthine oxidoreductase apoprotein into the active enzyme in mouse L929 fibroblastic cells.

    PubMed Central

    Falciani, F; Terao, M; Goldwurm, S; Ronchi, A; Gatti, A; Minoia, C; Li Calzi, M; Salmona, M; Cazzaniga, G; Garattini, E

    1994-01-01

    The mouse L929 fibroblastic cell line presents low, but detectable, levels of the mRNA encoding xanthine oxidoreductase under basal conditions, and it responds to type I and type II interferons by inducing the expression of the transcript [Falciani, Ghezzi, Terao, Cazzaniga, and Garattini (1992) Biochem. J. 285, 1001-1008]. This cell line, however, does not show any detectable amount of xanthine oxidoreductase enzymic activity, either before or after treatment with the cytokines. Molybdenum(VI) salts, in the millimolar range, are capable of activating xanthine oxidoreductase in L929 cells both under basal conditions and after treatment with interferon-alpha. The increase is observed in mouse L929 as well as in clones derived from it, but not in many other human and mouse cell lines. The induction observed in L929 cells is post-translational in nature and it is insensitive to cycloheximide, indicating that the molybdenum ion converts a pool of inactive xanthine oxidoreductase apoenzyme into its holoenzymic form. When grown in the absence of sodium molybdate, the L929 cell line has undetectable intracellular levels of the molybdenum cofactor, since the cell extracts are unable to complement the nitrate reductase defect of the nit-1 mutant of Neurospora crassa. L929 cells grown in the presence of millimolar concentrations of sodium molybdate, however, become competent to complement the nit-1 defect. L929 cells accumulate molybdenum ion inside the intracellular compartment as efficiently as TEnd cells, a mouse endothelial cell line that expresses xanthine oxidoreductase activity both under basal conditions and after treatment with interferon-gamma, suggesting that L929 cells have a defect in one or more of the metabolic steps leading to the synthesis of the molybdenum cofactor. Images Figure 1 Figure 2 Figure 4 PMID:8129733

  3. Angiotensin-converting enzyme 2 inhibits high-mobility group box 1 and attenuates cardiac dysfunction post-myocardial ischemia

    PubMed Central

    Zhang, Juan; Wang, Lei; Shenoy, Vinayak; Krause, Eric; Oh, S. Paul; Pepine, Carl J; Katovich, Michael J

    2015-01-01

    High-mobility group box 1 (HMGB1) triggers and amplifies inflammation cascade following ischemic injury, and its elevated levels are associated with adverse clinical outcomes in patients with myocardial infarction (MI). Angiotensin-converting enzyme 2 (ACE2), a key member of vasoprotective axis of the renin-angiotensin system (RAS), regulates cardiovascular functions and exerts beneficial effects in cardiovascular disease. However, the association between HMGB1 and ACE2 has not been studied. We hypothesized that overexpression of ACE2 provides cardioprotective effects against MI via inhibiting HMGB1 and inflammation. ACE2 knock-in (KI) mice and littermate wild-type (WT) controls were subjected to either sham or coronary artery ligation surgery to induce MI. Heart function was assessed 4 weeks after surgery using echocardiography and Millar catheterization. Tissues were collected for histology and analysis of the expression of HMGB1, RAS components, and inflammatory cytokines. ACE2 in the heart of the ACE2 KI mice was 58-fold higher than WT controls. ACE2-MI mice exhibited a remarkable preservation of cardiac function and reduction of infarct size in comparison to WT-MI mice. Notably, ACE2 overexpression significantly reduced the MI-induced increase in apoptosis, macrophage infiltration, and HMGB1 and pro-inflammatory cytokine expression (TNF-α and IL-6). Moreover, in an in vitro study, ACE2 activation prevented the hypoxia-induced cell death and upregulation of HMGB1 in adult cardiomyocytes. This protective effect is correlated with downregulation of HMGB1 and downstream pro-inflammatory cascades, which could be useful for the development of novel treatment for ischemic heart disease. PMID:26498282

  4. Aliskiren in Patients Failing to Achieve Blood Pressure Targets With Angiotensin Converting Enzyme Inhibitors or Angiotensin Receptor Blockers

    PubMed Central

    Hawkins, Elizabeth B.; Ling, Hua; Burns, Tammy L.; Mooss, Aryan N.; Hilleman, Daniel E.

    2012-01-01

    Background To assess the efficacy of aliskiren in patients failing to reach blood pressure (BP) goals with angiotensin converting enzyme inhibitor (ACEI) or angiotensin receptor blocker (ARB). Methods A total of 107 patients who failed to reach BP goals on ACEI or ARB were switched to aliskiren. Changes in BP were determined during maximal ACEI, ARB, or aliskiren therapy. Results Mean reduction in sBP and dBP with ACEI was 8.5 ± 6.3 mmHg and 6.0 ± 4.7 mmHg, respectively. Mean reduction in sBP and dBP with ARB was 8.3 ± 6.7 mmHg and 5.0 ± 5.2 mmHg, respectively. Mean reduction in sBP and dBP with aliskiren 150 mg/d was 6.7 ± 5.4 mmHg and 5.4 ± 4.8 mmHg, respectively. Mean reduction in sBP and dBP with aliskiren 300 mg/d was 8.6 ± 6.3 mmHg and 6.0 ± 4.9 mmHg, respectively. BP reductions between ACEI, ARB, and aliskiren were not significantly different. Conclusions Aliskiren is ineffective in patients failing ACEI or ARB therapy. Given the label changes restricting the use of aliskiren in combination with ACEI and ARB, excess cost compared to ACEI and ARB, and a paucity of outcome data, there is a limited role for aliskiren in practice.

  5. Influence of Angiotensin-Converting-Enzyme Gene Polymorphism on Echocardiographic Data of Patients with Ischemic Heart Failure

    PubMed Central

    Duque, Gustavo Salgado; da Silva, Dayse Aparecida; de Albuquerque, Felipe Neves; Schneider, Roberta Siuffo; Gimenez, Alinne; Pozzan, Roberto; Rocha, Ricardo Mourilhe; de Albuquerque, Denilson Campos

    2016-01-01

    Background Association between angiotensin-converting-enzyme (ACE) gene polymorphisms and different clinical and echocardiographic outcomes has been described in patients with heart failure (HF) and coronary artery disease. Studying the genetic profile of the local population with both diseases is necessary to assess the occurrence of that association. Objectives To assess the frequency of ACE gene polymorphisms in patients with ischemic HF in a Rio de Janeiro population, as well as its association with echocardiographic findings. Methods Genetic assessment of I/D ACE polymorphism in association with clinical, laboratory and echocardiographic analysis of 99 patients. Results The allele frequency was: 53 I alleles, and 145 D alleles. Genotype frequencies were: 49.5% DD; 47.48% DI; 3.02% II. Drug treatment was optimized: 98% on beta-blockers, and 84.8% on ACE inhibitors or angiotensin-receptor blocker. Echocardiographic findings: difference between left ventricular diastolic diameters (ΔLVDD) during follow-up: 2.98±8.94 (DD) vs. 0.68±8.12 (DI) vs. -11.0±7.00 (II), p=0.018; worsening during follow-up of the LV systolic diameter (LVSD): 65.3% DD vs. 19.0% DI vs. 0.0% II, p=0.01; of the LV diastolic diameter (LVDD): 65.3% DD vs. 46.8% DI vs. 0.0% II, p=0.03; and of the LV ejection fraction (LVEF): 67.3% DD vs. 40.4% DI vs. 33.3% II, p=0.024. Correlated with D allele: ΔLVEF, ΔLVSD, ΔLVDD. Conclusions More DD genotype patients had worsening of the LVEF, LVSD and LVDD, followed by DI genotype patients, while II genotype patients had the best outcome. The same pattern was observed for ΔLVDD. PMID:27812677

  6. MicroRNAs mediate the cardioprotective effect of angiotensin-converting enzyme inhibition in acute kidney injury.

    PubMed

    Rana, Indrajeetsinh; Velkoska, Elena; Patel, Sheila K; Burrell, Louise M; Charchar, Fadi J

    2015-12-01

    Cardiovascular disease, including cardiac hypertrophy, is common in patients with kidney disease and can be partially attenuated using blockers of the renin-angiotensin system (RAS). It is unknown whether cardiac microRNAs contribute to the pathogenesis of cardiac hypertrophy or to the protective effect of RAS blockade in kidney disease. Using a subtotal nephrectomy rat model of kidney injury, we investigated changes in cardiac microRNAs that are known to have direct target genes involved in the regulation of apoptosis, fibrosis, and hypertrophy. The effect of treatment with the angiotensin-converting enzyme (ACE) inhibitor ramipril on cardiac microRNAs was also investigated. Kidney injury led to a significant increase in cardiac microRNA-212 and microRNA-132 expression. Ramipril reduced cardiac hypertrophy, attenuated the increase in microRNA-212 and microRNA-132, and significantly increased microRNA-133 and microRNA-1 expression. There was altered expression of caspase-9, B cell lymphoma-2, transforming growth factor-β, fibronectin 1, collagen type 1A1, and forkhead box protein O3, which are all known to be involved in the regulation of apoptosis, fibrosis, and hypertrophy in cardiac cells while being targets for the above microRNAs. ACE inhibitor treatment increased expression of microRNA-133 and microRNA-1. The inhibitory action of ACE inhibitor treatment on increased cardiac NADPH oxidase isoform 1 expression after subtotal nephrectomy surgery suggests that inhibition of oxidative stress is also one of mechanism of ACE inhibitor-mediated cardioprotection. These finding suggests the involvement of microRNAs in the cardioprotective action of ACE inhibition in acute renal injury, which is mediated through an inhibitory action on profibrotic and proapoptotic target genes and stimulatory action on antihypertrophic and antiapoptotic target genes.

  7. Antihypertensive efficacy of the angiotensin receptor blocker azilsartan medoxomil compared with the angiotensin-converting enzyme inhibitor ramipril

    PubMed Central

    Bönner, G; Bakris, G L; Sica, D; Weber, M A; White, W B; Perez, A; Cao, C; Handley, A; Kupfer, S

    2013-01-01

    Drug therapy often fails to control hypertension. Azilsartan medoxomil (AZL-M) is a newly developed angiotensin II receptor blocker with high efficacy and good tolerability. This double-blind, controlled, randomised trial compared its antihypertensive efficacy and safety vs the angiotensin-converting enzyme inhibitor ramipril (RAM) in patients with clinic systolic blood pressure (SBP) 150–180 mm Hg. Patients were randomised (n=884) to 20 mg AZL-M or 2.5 mg RAM once daily for 2 weeks, then force-titrated to 40 or 80 mg AZL-M or 10 mg RAM for 22 weeks. The primary endpoint was change in trough, seated, clinic SBP. Mean patient age was 57±11 years, 52.4% were male, 99.5% were Caucasian. Mean baseline BP was 161.1±7.9/94.9±9.0 mm Hg. Clinic SBP decreased by 20.6±0.95 and 21.2±0.95 mm Hg with AZL-M 40 and 80 mg vs12.2±0.95 mm Hg with RAM (P<0.001 for both AZL-M doses). Adverse events leading to discontinuation were less frequent with AZL-M 40 and 80 mg (2.4% and 3.1%, respectively) than with RAM (4.8%). These data demonstrated that treatment of stage 1–2 hypertension with AZL-M was more effective than RAM and better tolerated. PMID:23514842

  8. Convergent evidences from human and animal studies implicate angiotensin I-converting enzyme activity in cognitive performance in schizophrenia

    PubMed Central

    Gadelha, A; Vendramini, A M; Yonamine, C M; Nering, M; Berberian, A; Suiama, M A; Oliveira, V; Lima-Landman, M T; Breen, G; Bressan, R A; Abílio, V; Hayashi, M A F

    2015-01-01

    In schizophrenia (SCZ), higher angiotensin I-converting enzyme (ACE) levels have been reported in patient's blood and cerebrospinal fluid (CSF). Hereby, we propose to explore whether the ACE activity levels are associated to cognitive performance in SCZ. Seventy-two patients with SCZ or schizoaffective disorder diagnosis, and 69 healthy controls (HCs) underwent a cognitive battery with parallel collection of peripheral blood samples to measure ACE activity. Significant higher ACE activity levels were confirmed in the plasma of SCZ patients compared with HCs (Student's t=−5.216; P<0.001). ACE activity significantly correlated to Hopkins delayed recall measures (r=−0.247; P=0.004) and Hopkins total (r=−0.214; P=0.012). Subjects grouped as high ACE activity (above average) had worse performance compared with low ACE activity level group for Hopkins delayed recall measure, even after correction for clinical condition, age, gender and years of education (P=0.029). The adjusted R squared for this final model was 0.343. This result was evident only comparing extreme groups for ACE activity, when splitting the sample in three groups with similar number of subjects. To clarify this finding, we performed an evaluation of the cognitive performance of transgenic mice with three copies of ACE gene in novel object recognition (NOR) test, which showed that such animals presented impairment in NOR (P<0.05) compared with two copies of wild-type animals. The results observed in SCZ patients and animal model suggest both the association of ACE to cognitive deficits in SCZ. This finding may support the evaluation of novel treatment protocols and/or of innovative drugs for specific intervention of cognitive deficits in SCZ envisioning concomitant ACE activity and behavior evaluations. PMID:26645626

  9. Comparative effects of a novel angiotensin-converting enzyme inhibitor versus captopril on plasma angiotensins after myocardial infarction.

    PubMed

    Flores-Monroy, Jazmín; Ferrario, Carlos M; Valencia-Hernández, Ignacio; Hernández-Campos, Maria Elena; Martínez-Aguilar, Luisa

    2014-01-01

    The compound 4-tert-butyl-2,6-bis(thiomorpholin-4-ylmethyl)phenol (TBTIF) has molecular characteristics similar to angiotensin-converting enzyme (ACE) inhibitors of the sulfhydryl subclass. To assess its value as a new therapeutic agent, we performed a comparative analysis of the effect of TBTIF versus captopril on the circulating levels of angiotensin (Ang) peptides and bradykinin as well as ACE and ACE2 expression after myocardial infarction. Male Wistar rats were divided into four groups: (1) sham-operated rats; (2) rats subjected to 48 h of coronary artery ligation; (3) rats administered captopril (1 mg/kg, i.m.), and (4) a similar group of rats given TBTIF (1 mg/kg, i.m.). Both drugs were administered 30 min before coronary artery ligation and again 24 h later. Acute myocardial infarction lowered both systolic and left ventricular systolic blood pressures compared to the sham group and increased plasma levels of Ang I, Ang II, Ang(1-7) and Ang(1-12). Administration of either captopril or TBTIF reversed the increases in plasma angiotensins. Interestingly, the levels of plasma Ang(1-7) achieved by administration of TBTIF reached values higher than those recorded with captopril. Both agents reversed the decreases in plasma concentrations of bradykinin; in addition, TBTIF upregulated ACE expression, while both agents suppressed the ACE2 upregulation induced by myocardial infarction. These results demonstrate a beneficial effect of the novel compound TBTIF in suppressing the acute surge in the circulating renin-angiotensin system activity induced by myocardial infarction. The greater effects of this compound in augmenting plasma Ang(1-7) concentrations may be highly significant as drugs which augment the concentration of this heptapeptide will exert cardioprotective actions in part by suppressing the hypertrophic and profibrotic actions of Ang II.

  10. Effect of Antiviral Therapy on Serum Activity of Angiotensin Converting Enzyme in Patients with Chronic Hepatitis C

    PubMed Central

    Husic-Selimovic, Azra; Sofic, Amela; Huskic, Jasminko; Bulja, Deniz

    2016-01-01

    Introduction: Renin-angiotenzin system (RAS) is frequently activated in patients with chronic liver disease. Angiotenzin - II (AT-II), produced by angiotenzin converting enzyme (ACE), has many physiological effects, including an important role in liver fibrogenesis. Combined antiviral therapy with PEG-IFN and ribavirin besides its antiviral effect also leads to a reduction in liver parenchyma fibrosis. Aim of the study: Determining the value of ACE in serum of patients with chronic hepatitis C before and after combined antiviral therapy, as well as the value of ACE activities in sera of the control group. Materials and methods: We studied 50 patients treated at Gastroenterohepatology Department, in the time-period of four years. Value of ACE in serum was determined by Olympus AU 400 device, with application of kit “Infinity TN ACE Liquid Stable Reagent”. HCV RNA levels in sera were measured by real time PCR. HCV RNA test was performed with modular analysis of AMPLICOR and COBAS AMPLICOR HCV MONITOR test v2.0, which has proved infection and was used for quantification of the viruses and monitoring of the patients’ response to therapy. Liver histology was evaluated in accordance with the level of necroinflammation activity and stage of fibrosis. Results: Serum activities of ACE in chronic hepatitis C patients is statistically higher than the values in the control group (p=0.02). Antiviral therapy in chronic hepatitis C patients statistically decreases serum activities of ACE (p= 0.02) and indirectly affects fibrogenesis of the liver parenchyma. Correlation between ACE and ALT activity after the therapy was proved (0.3934). Conclusion: Our findings suggest that the activity of ACE in serum is a good indirect parameter of the liver damage, and could be used as an indirect prognostic factor of the level of liver parenchyma damage. Serum activity of ACE can be used as a parameter for non-invasive assessment of intensity of liver damage. PMID:27147779

  11. Angiotensin converting enzyme gene polymorphism is associated with severity of coronary artery disease in men with high total cholesterol levels.

    PubMed

    Borzyszkowska, Joanna; Stanislawska-Sachadyn, Anna; Wirtwein, Marcin; Sobiczewski, Wojciech; Ciecwierz, Dariusz; Targonski, Radoslaw; Gruchala, Marcin; Rynkiewicz, Andrzej; Limon, Janusz

    2012-05-01

    This study examines whether renin-angiotensin-aldosterone system gene polymorphisms: ACE (encoding for angiotensin converting enzyme) c.2306-117_404 I/D, AGTR1 (encoding for angiotensin II type-1 receptor) c.1080*86A>C and CYP11B2 (encoding for aldosterone synthase) c.-344C>T are associated with the extension of coronary atherosclerosis in a group of 647 patients who underwent elective coronary angiography. The extension of CAD was evaluated using the Gensini score. The polymorphisms were determined by PCR and RFLP assays. The associations between genotypes and the extent of coronary atherosclerosis were tested by the Kruskal-Wallis test, followed by pairwise comparisons using Wilcoxon test. The population has been divided into groups defined by: sex, smoking habit, past myocardial infarction, BMI (>, ≤ 25), age (>, ≤ 55), diabetes mellitus, level of total cholesterol (>, ≤ 200 mg/dl), LDL cholesterol (>, ≤ 130 mg/dl), HDL cholesterol (>, ≤ 40 mg/dl), triglycerides (>, ≤ 150 mg/dl). Significant associations between the ACE c.2306-117_404 I/D polymorphism and the Gensini score in men with high total cholesterol levels (P(Kruskal-Wallis) = 0.008; P(adjusted) = 0.009), high level of LDL cholesterol (P(Kruskal-Wallis) = 0.016; P(adjusted) = 0.028) and low level of HDL cholesterol (P(Kruskal-Wallis) = 0.04; P(adjusted) = 0.055) have been found. No association between the AGTR1 c.1080*86A>C and CYP11B2 c.-344C>T and the Gensini score has been found. These results suggest that men who carry ACE c.2306-117_404 DD genotype and have high total cholesterol, high LDL cholesterol and low HDL cholesterol levels may be predisposed to the development of more severe CAD.

  12. Lack of Association between Angiotensin Converting Enzyme I/D Polymorphism and Unexplained Recurrent Miscarriage in Saudi Arabia

    PubMed Central

    Al-Mukaynizi, Fatimah Basil; AlKhuriji, Afrah; Babay, Zaineb; Addar, Mohammad; AlDaihan, Sooad; Alanazi, Mohammad

    2016-01-01

    Summary Background An insertion/deletion (I/D) polymorphism in the angiotensin converting enzyme (ACE) gene has been associated with recurrent miscarriage (RM) in several populations. We initiated this study to determine the association, if any, between the I/D polymorphism of ACE gene and RM in Saudi females. Method This study was conducted on 61 Saudi females suffering from RM (mean age: 34.1±6.2 years; range 15–45) attending clinics at King Khalid University Hospital, and 59 age matched females who had at least 2 children, as controls. Blood samples were drawn in EDTA tubes by venipuncture. DNA was extracted using the Puregene DNA purification kits. Insertion/Deletion (I/D) polymorphism of ACE gene was investigated by amplifying the genomic DNA by PCR using gene-specific primers. A single 190 bp or 490 bp band was obtained in the homozygous cases for the D allele or I allele, respectively, while the presence of both 190 and 490 bp bands indicated heterozygosity (ID). Statistical analysis Deviation from Hardy-Weinberg equilibrium was determined (http://ihg.gsf.de/cgi-bin/hw/hwa1.pl). A standard chi-square (χ2) test was used for comparing the genotype and allele frequencies in the two groups and Students’t’ test and χ2 test were employed to compare values between the two groups. P<0.05 was considered statistically significant. Results The frequencies of DD, ID, and II genotypes were 56.7%, 29.5% and 4.9%, respectively, in females with RM and 54.2%, 42.3% and 3.3% respectively in the control group, but the difference was not statistically significant. Conclusion In some populations, meta-analyses showed an association between I/D polymorphism and RM risk, and the D allele was implicated as an increased risk factor for RM. However, this association was not apparent in the Saudi females. PMID:28356877

  13. Outcomes of preoperative angiotensin-converting enzyme inhibitor therapy in patients undergoing isolated coronary artery bypass grafting.

    PubMed

    Bandeali, Salman J; Kayani, Waleed T; Lee, Vei-Vei; Pan, Wei; Elayda, Mac Arthur A; Nambi, Vijay; Jneid, Hani M; Alam, Mahboob; Wilson, James M; Birnbaum, Yochai; Ballantyne, Christie M; Virani, Salim S

    2012-10-01

    The association between preoperative use of angiotensin-converting enzyme (ACE) inhibitors and outcomes after coronary artery bypass grafting (CABG) remain controversial. Our aim was to study in-hospital outcomes after isolated CABG in patients on preoperative ACE inhibitors. A retrospective analysis of 8,889 patients who underwent isolated CABG from 2000 through 2011 was conducted. The primary outcome of interest was the incidence of major adverse events (MAEs) defined as a composite of mortality, postoperative renal dysfunction, myocardial infarction, stroke, and atrial fibrillation during index hospitalization. The secondary outcome was the incidence of individual outcomes included in MAEs. Logistic regression analyses were performed. Of 8,889 patients, 3,983 (45%) were on preoperative ACE inhibitors and 4,906 (55%) were not. Overall incidence of MAEs was 38.1% (n = 1,518) in the ACE inhibitor group compared to 33.6% (n = 1,649) in the no-ACE inhibitor group. Preoperative use of ACE inhibitors was independently associated with MAEs (odds ratio 1.13, 95% confidence interval 1.03 to 1.24), most of which was driven by a statistically significant increase in postoperative renal dysfunction (odds ratio 1.18, 95% confidence interval 1.03 to 1.36) and atrial fibrillation (odds ratio 1.15, 95% confidence interval 1.05 to 1.27). In-hospital mortality, postoperative myocardial infarction, and stroke were not significantly associated with preoperative ACE inhibitor use. Analyses performed after excluding patients with low ejection fractions yielded similar results. In conclusion, preoperative ACE inhibitor use was associated with an increased risk of MAEs after CABG, in particular postoperative renal dysfunction and atrial fibrillation.

  14. Association of exercise training and angiotensin-converting enzyme 2 activator improves baroreflex sensitivity of spontaneously hypertensive rats.

    PubMed

    Lopes, P R; Moreira, M C S; Marques, S M; Pinto, I S J; Macedo, L M; Silva, C C; Freiria-Oliveira, A H; Rebelo, A C S; Reis, A A S; Rosa, D A; Ferreira-Neto, M L; Castro, C H; Pedrino, G R

    2016-08-01

    The present study sought to determine cardiovascular effects of aerobic training associated with diminazene aceturate (DIZE), an activator of the angiotensin converting enzyme 2, in spontaneously hypertensive rats (SHRs). Male SHRs (280-350 g) were either subjected to exercise training or not (sedentary group). The trained group was subjected to 8 weeks of aerobic training on a treadmill (five times a week, lasting 60 min at an intensity of 50-60% of maximum aerobic speed). In the last 15 days of the experimental protocol, these groups were redistributed into four groups: i) sedentary SHRs with daily treatment of 1 mg/kg DIZE (S+D1); ii) trained SHRs with daily treatment of 1 mg/kg DIZE (T+D1); iii) sedentary SHRs with daily treatment of vehicle (S+V); and iv) trained SHRs with daily treatment of vehicle (T+V). After treatment, SHRs were anesthetized and subjected to artery and femoral vein cannulation prior to the implantation of ECG electrode. After 24 h, mean arterial pressure (MAP) and heart rate (HR) were recorded; the baroreflex sensitivity and the effect of double autonomic blockade (DAB) were evaluated in non-anesthetized SHRs. DIZE treatment improved baroreflex sensitivity in the T+D1 group as compared with the T+V and S+D1 groups. The intrinsic heart rate (IHR) and MAP were reduced in T+D1 group as compared with T+V and S+D1 groups. Hence, we conclude that the association of exercise training with DIZE treatment improved baroreflex function and cardiovascular regulation.

  15. Ocular Inserts for Sustained Release of the Angiotensin-Converting Enzyme 2 Activator, Diminazene Aceturate, to Treat Glaucoma in Rats

    PubMed Central

    Nogueira, José Carlos; Fulgêncio, Gustavo de Oliveira; Ribeiro, Tatiana Gomes; Castilho, Rachel Oliveira; Yoshida, Maria Irene; Fuscaldi, Leonardo Lima; Fernandes, Simone Odília Antunes; Cardoso, Valbert Nascimento; Cronemberger, Sebastião; Faraco, André Augusto Gomes; Ferreira, Anderson José

    2015-01-01

    The aim of this study was to develop and evaluate the effects of chitosan inserts for sustained release of the angiotensin-converting enzyme 2 (ACE2) activator, diminazene aceturate (DIZE), in experimental glaucoma. Monolayer DIZE loaded inserts (D+I) were prepared and characterized through swelling, attenuated total reflectance Fourier transformed infrared spectroscopy (ATR-FTIR), differential scanning calorimetry (DSC) and in vitro drug release. Functionally, the effects of D+I were tested in glaucomatous rats. Glaucoma was induced by weekly injections of hyaluronic acid (HA) into the anterior chamber and intraocular pressure (IOP) measurements were performed. Retinal ganglion cells (RGC) and optic nerve head cupping were evaluated in histological sections. Biodistribution of the drug was accessed by scintigraphic images and ex vivo radiation counting. We found that DIZE increased the swelling index of the inserts. Also, it was molecularly dispersed and interspersed in the polymeric matrix as a freebase. DIZE did not lose its chemical integrity and activity when loaded in the inserts. The functional evaluation demonstrated that D+I decreased the IOP and maintained the IOP lowered for up to one month (last week: 11.0±0.7 mmHg). This effect of D+I prevented the loss of RGC and degeneration of the optic nerve. No toxic effects in the eyes related to application of the inserts were observed. Moreover, biodistribution studies showed that D+I prolonged the retention of DIZE in the corneal site. We concluded that D+I provided sustained DIZE delivery in vivo, thereby evidencing the potential application of polymeric-based DIZE inserts for glaucoma management. PMID:26204514

  16. Caspase-1 (interleukin-1beta-converting enzyme) is inhibited by the human serpin analogue proteinase inhibitor 9.

    PubMed Central

    Annand, R R; Dahlen, J R; Sprecher, C A; De Dreu, P; Foster, D C; Mankovich, J A; Talanian, R V; Kisiel, W; Giegel, D A

    1999-01-01

    The regulation of caspases, cysteine proteinases that cleave their substrates after aspartic residues, is poorly understood, even though they are involved in tightly regulated cellular processes. The recently discovered serpin analogue proteinase inhibitor 9 (PI9) is unique among human serpin analogues in that it has an acidic residue in the putative specificity-determining position of the reactive-site loop. We measured the ability of PI9 to inhibit the amidolytic activity of several caspases. The hydrolysis of peptide substrates by caspase-1 (interleukin-1beta-converting enzyme), caspase-4 and caspase-8 is inhibited by PI9 in a time-dependent manner. The rate of reaction of caspase-1 with PI9, as well as the rate of substrate hydrolysis of the initial caspase-PI9 complex, shows a hyperbolic dependence on the concentration of PI9, indicative of a two-step kinetic mechanism for inhibition with an apparent second-order rate constant of 7x10(2) M(-1).s(-1). The hydrolysis of a tetrapeptide substrate by caspase-3 is not inhibited by PI9. The complexes of caspase-1 and caspase-4 with PI9 can be immunoprecipitated but no complex with caspase-3 can be detected. No complex can be immunoprecipitated if the active site of the caspase is blocked with a covalent inhibitor. These results show that PI9 is an inhibitor of caspase-1 and to a smaller extent caspase-4 and caspase-8, but not of the more distantly related caspase-3. PI9 is the first example of a human serpin analogue that inhibits members of this class of cysteine proteinases. PMID:10477277

  17. Angiotensin converting enzyme inhibitors and angiotensin receptor blockers in the treatment of hypertension: should they be used together?

    PubMed

    Verdecchia, Paolo; Angeli, Fabio; Mazzotta, Giovanni; Ambrosio, Giuseppe; Reboldi, Gianpaolo

    2010-11-01

    The combined use of angiotensin converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) poses a dilemma to clinicians. On the one hand, indirect evidence from compelling, but still surrogate outcome measures such as blood pressure and proteinuria suggest some merits of this combination. On the other hand, the outcome benefits of the ACEIs+ARBs combination in morbidity/mortality trials remain confined to patients with severe congestive heart failure (CHF) and reduced ejection fraction. Incidentally, most of the benefit offered by the ACEIs+ARBs combination in these patients was not driven by mortality, but by fewer rehospitalizations for CHF. Even in patients with renal disease and proteinuria, the combined use of ACEIs and ARBs, although highly effective in reducing urinary protein excretion, has not yet been proven to significantly delay end-stage renal disease and the need for dialysis. In the Ongoing Telmisartan Alone and In Combination With Ramipril Global Endpoint Trial (ONTARGET), the dual blockade of the renin angiotensin system did not produce additional outcome benefit over that afforded by ACE inhibition alone. Notably, however, patients with BP >160/100 mmHg at entry were excluded from ONTARGET, thus limiting the applicability of these results to the treatment of hypertension. The European Society of Hypertension guidelines do not suggest large-scale use of the ACEIs+ARBs combination in patients with hypertension. However, patients with resistant hypertension, particularly if proteinuria coexists, could benefit from this combination, which however requires close monitoring for adverse events, including hyperkalemia and worsening renal function.

  18. Effect of angiotensin I-converting enzyme and α-actinin-3 gene polymorphisms on sport performance.

    PubMed

    Gunel, Tuba; Gumusoglu, Ece; Hosseini, Mohammad Kazem; Yilmazyildirim, Eda; Dolekcap, Ismail; Aydinli, Kilic

    2014-04-01

    Genetic polymorphism is considered to be associated with human physical performance. The angiotensin I-converting enzyme insertion/deletion (ACE I/D) and the α-actinin-3 gene (ACTN3) R577X polymorphisms have been widely investigated for such associations, and functional ACE I/D and ACTN3 R577X polymorphisms have been associated with sprinter performance. The aim of this study was to determine the effect of these polymorphisms on sport performance among 37 elite athletes and 37 healthy controls. The ACE II genotype was identified in 32.43% of the control group and 8.11% of elite athletes, the DD genotype in 37.84% of the control group and 51.35% of the elite athletes, and the ID genotype in 29.73% of the control group and 40.54% of the elite athletes. With regard to the ACTN3 gene, the XX genotype, which confers an advantage for endurance activities, was identified in 10.81% of the control group and 35.14% of the elite athletes. The XX genotype was observed more frequently than the RR genotype (advantageous for sprinting), which was identified in 2.70% of the control group and 10.81% of elite athletes. The RX genotype (observed in 86.48% of the control group and in 54.05% of the elite athletes) was the most common genotype of the individuals in the present study. The study showed that ACTN3 and ACE gene polymorphisms have an effect on muscle power; however, larger studies are required.

  19. Effects of angiotensin-converting enzyme inhibitor, captopril, on bone of mice with streptozotocin-induced type 1 diabetes.

    PubMed

    Diao, Teng-Yue; Pan, Hai; Gu, Sa-Sa; Chen, Xi; Zhang, Fang-Yi; Wong, Man-Sau; Zhang, Yan

    2014-05-01

    There are contradictory results about the effect of angiotensin-converting enzyme inhibitors (ACEIs) on bone. This study was performed to address the skeletal renin-angiotensin system (RAS) activity and the effects of the ACEI, captopril, on the bone of streptozotocin-induced type 1 diabetic mice. Histochemical assessment on bone paraffin sections was conducted by Safranin O staining and tartrate-resistant acid phosphatase staining. Micro-computed tomography was performed to analyze bone biological parameters. Gene and protein expression were determined by real-time polymerase chain reaction and immunoblotting, respectively. Type 1 diabetic mice displayed osteopenia phenotype and captopril treatment showed no osteoprotective effects in diabetic mice as shown by the reduction of bone mineral density, trabecular thickness and bone volume/total volume. The mRNA expression of ACE and renin receptor, and the protein expression of renin and angiotensin II were markedly up-regulated in the bone of vehicle-treated diabetic mice compared to those of non-diabetic mice, and these molecular changes of skeletal RAS components were effectively inhibited by treatment with captopril. However, treatment with captopril significantly elevated serum tartrate-resistant acid phosphatase 5b levels, reduced the ratio of osteoprotegerin/receptor activator of nuclear factor-κB ligand expression, increased carbonic anhydrase II mRNA expression and the number of matured osteoclasts and decreased transforming growth factor-β and osteocalcin mRNA expression in the tibia compared to those of diabetic mice. The present study demonstrated that the use of the ACEI, captopril, has no beneficial effect on the skeletal biological properties of diabetic mice. However, this could be attributed, at least partially, to its suppression of osteogenesis and stimulation of osteoclastogenesis, even though it could effectively inhibit high activity of local RAS in the bone of diabetic mice.

  20. Angiotensin-Converting Enzyme Inhibitor Use by Older Adults Is Associated with Greater Functional Responses to Exercise

    PubMed Central

    Buford, Thomas W.; Manini, Todd M.; Hsu, Fang-Chi; Cesari, Matteo; Anton, Stephen D.; Nayfield, Susan; Stafford, Randall S.; Church, Timothy S.; Pahor, Marco; Carter, Christy S.

    2013-01-01

    OBJECTIVES To assess the association between angiotensin converting enzyme inhibitors (ACEis) and improvements in the physical function of older adults in response to chronic exercise training. DESIGN Secondary analysis of the Lifestyle Interventions and Independence for Elders Pilot (LIFE-P) study, a multisite randomized clinical trial to evaluate the effects of chronic exercise on the physical function of older adults at risk for mobility disability. SETTING Four academic research centers within the United States. PARTICIPANTS Four hundred twenty-four individuals aged 70 to 89 with mild to moderate functional impairments categorized for this analysis as ACEi users, users of other antihypertensive drugs, or antihypertensive nonusers. INTERVENTION A 12-month intervention of structured physical activity (PA) or health education promoting successful aging (SA). MEASUREMENTS Change in walking speed during a 400-m test and performance on a battery of short-duration mobility tasks (Short Physical Performance Battery (SPPB)). RESULTS Physical activity significantly improved the adjusted walking speed of ACEi users (P < .001) but did not of nonusers. PA improved the adjusted SPPB score of ACEi users (P < .001) and of persons who used other antihypertensive drugs (P = .005) but not of antihypertensive nonusers (P = .91). The percentage of ACEi users deriving clinically significant benefit from exercise training for walking speed (30%) and SPPB score (48%) was dramatically higher than for nonusers (14% and 12%, respectively). CONCLUSION For older adults at risk for disability, exercise-derived improvements in physical function were greater for ACEi users than users of other antihypertensive drugs and antihypertensive nonusers. PMID:22726232

  1. A retrospective study of the effects of angiotensin receptor blockers and angiotensin converting enzyme inhibitors in diabetic nephropathy

    PubMed Central

    Pathak, Jahnavi V.; Dass, Ervilla E.

    2015-01-01

    Objective: Till date, several studies have compared angiotensin converting enzyme (ACE) inhibitors and angiotensin receptor blockers (ARBs) in terms of delaying the progression of diabetic nephropathy. But the superiority of one drug class over the other remains unsettled. This study has retrospectively compared the effects of ACE inhibitors and ARBs in diabetic nephropathy. The study aims to compare ACE inhibitors and ARBs in terms of delaying or preventing the progression of diabetic nephropathy, association between blood pressure (B.P) and urinary albumin and also B.P and serum creatinine with ACE inhibitor and ARB, know the percentage of hyperkalemia in patients of diabetic nephropathy receiving ACE inhibitor or ARB. Settings and Design: A total of 134 patients diagnosed with diabetic nephropathy during the years 2001–2010 and having a complete follow-up were studied, out of which 99 were on ARB (63 patients of Losartan and 36 of Telmisartan) and 35 on ACE inhibitor (Ramipril). Subjects and Methods: There was at least 1-month of interval between each observation made and also between the date of treatment started and the first reading that is, the observation of the 1st month. In total, three readings were taken that is, of the 1st, 2nd and 3rd month after the treatment started. Comparison of the 1st and 3rd month after the treatment started was done. Mean ± standard deviation, Paired t-test, and Chi-square were used for the analysis of the data. Results: The results reflect that ARBs (Losartan and Telmisartan) when compared to ACE inhibitor (Ramipril) are more effective in terms of delaying the progression of diabetic nephropathy and also in providing renoprotection. Also, ARBs have the property of simultaneously decreasing the systolic B.P and albuminuria when compared to ACE inhibitor (Ramipril). Conclusions: Angiotensin receptor blockers are more renoprotective than ACE inhibitors and also provide better cardioprotection. PMID:25878372

  2. Pioglitazone, a PPARγ agonist, provides comparable protection to angiotensin converting enzyme inhibitor ramipril against adriamycin nephropathy in rat.

    PubMed

    Ochodnicky, Peter; Mesarosova, Lucia; Cernecka, Hana; Klimas, Jan; Krenek, Peter; Goris, Maaike; van Dokkum, Richard P E; Henning, Robert H; Kyselovic, Jan

    2014-05-05

    Peroxisome proliferator-activated receptor γ (PPARγ) agonists have been shown to ameliorate diabetic nephropathy, but much less are known about their effects in non-diabetic nephropathies. In the present study, metabolic parameters, blood pressure, aortic endothelial function along with molecular and structural markers of glomerular and tubulointerstitial renal damage, were studied in a rat model of normotensive nephropathy induced by adriamycin and treated with PPARγ agonist pioglitazone (12mg/kg, po), angiotensin converting enzyme (ACE) inhibitor ramipril (1mg/kg, po) or their combination. Pioglitazone had no effect on systolic blood pressure, marginally reduced glycemia and improved aortic endothelium-dependent relaxation. In the kidney, pioglitazone prevented the development of proteinuria and focal glomerulosclerosis to the similar extent as blood-pressure lowering ramipril. Renoprotection provided by either treatment was associated with a reduction in the cortical expression of profibrotic plasminogen activator inhibitor-1 and microvascular damage-inducing endothelin-1, and a limitation of interstitial macrophage influx. Treatment with PPARγ agonist, as well as ACE inhibitor comparably affected renal expression of the renin-angiotensin system (RAS) components, normalizing increased renal expression of ACE and enhancing the expression of Mas receptor. Interestingly, combined pioglitazone and ramipril treatment did not provide any additional renoprotection. These results demonstrate that in a nondiabetic renal disease, such as adriamycin-induced nephropathy, PPARγ agonist pioglitazone provides renoprotection to a similar extent as an ACE inhibitor by interfering with the expression of local RAS components and attenuating related profibrotic and inflammatory mechanisms. The combination of the both agents, however, does not lead to any additional renal benefit.

  3. Enzyme

    MedlinePlus

    Enzymes are complex proteins that cause a specific chemical change in all parts of the body. For ... use them. Blood clotting is another example of enzymes at work. Enzymes are needed for all body ...

  4. Spontaneous release of angiotensin converting enzyme and interleukin 1 beta from peripheral blood monocytes from patients with rheumatoid arthritis under a serum free condition.

    PubMed Central

    Goto, M; Fujisawa, M; Yamada, A; Okabe, T; Takaku, F; Sasano, M; Nishioka, K

    1990-01-01

    Angiotensin converting enzyme (ACE) and interleukin 1 activities were assayed simultaneously in the serum free medium from the unstimulated peripheral blood monocytes from 32 patients with rheumatoid arthritis (RA), 11 patients with osteoarthritis, and 25 normal controls matched for age and sex. Angiotensin converting enzyme activity was raised in most (29/32) patients with RA and interleukin 1 activity (most of which was interleukin 1 beta) was enhanced in 11/32 patients with RA, while monocytes from only two patients with osteoarthritis, but from none of the controls, secreted a small amount of ACE alone in the culture condition. Monocytes from patients with early RA (disease duration less than 3 years) released significantly more ACE and interleukin 1 than those from late stage RA (disease duration greater than or equal to 3 years). PMID:2157375

  5. Top-down Targeted Metabolomics Reveals a Sulfur-Containing Metabolite with Inhibitory Activity against Angiotensin-Converting Enzyme in Asparagus officinalis.

    PubMed

    Nakabayashi, Ryo; Yang, Zhigang; Nishizawa, Tomoko; Mori, Tetsuya; Saito, Kazuki

    2015-05-22

    The discovery of bioactive natural compounds containing sulfur, which is crucial for inhibitory activity against angiotensin-converting enzyme (ACE), is a challenging task in metabolomics. Herein, a new S-containing metabolite, asparaptine (1), was discovered in the spears of Asparagus officinalis by targeted metabolomics using mass spectrometry for S-containing metabolites. The contribution ratio (2.2%) to the IC50 value in the crude extract showed that asparaptine (1) is a new ACE inhibitor.

  6. Role of Circulating Angiotensin Converting Enzyme 2 in Left Ventricular Remodeling following Myocardial Infarction: A Prospective Controlled Study

    PubMed Central

    Ortiz-Pérez, José T.; Riera, Marta; Bosch, Xavier; De Caralt, Teresa M.; Perea, Rosario J.; Pascual, Julio; Soler, María José

    2013-01-01

    Angiotensin-converting enzyme 2 (ACE2) cleaves Angiotensin-II to Angiotensin-(1–7), a cardioprotective peptide. Serum soluble ACE2 (sACE2) activity is raised in chronic heart failure, suggesting a compensatory role in left ventricular dysfunction. Our aim was to study the relationship between sACE2 activity, infarct size, left ventricular systolic function and remodeling following ST-elevation myocardial infarction (STEMI). A contrast-enhanced cardiac magnetic resonance study was performed acutely in 95 patients with first STEMI and repeated at 6 months to measure LV end-diastolic volume index, ejection fraction and infarct size. Baseline sACE2 activities, measured by fluorescent enzymatic assay 24 to 48 hours and at 7 days from admission, were compared to that obtained in 22 matched controls. Patients showed higher sACE2 at baseline than controls (104.4 [87.4–134.8] vs 74.9 [62.8–87.5] RFU/µl/hr, p<0.001). At seven days, sACE2 activity significantly increased from baseline (115.5 [92.9–168.6] RFU/µl/hr, p<0.01). An inverse correlation between sACE2 activity with acute and follow-up ejection fraction was observed (r = −0.519, p<0.001; r = −0.453, p = 0.001, respectively). Additionally, sACE2 directly correlated with infarct size (r = 0.373, p<0.001). Both, infarct size (β = −0.470 [95%CI:−0.691:−0.248], p<0.001) and sACE2 at 7 days (β = −0.025 [95%CI:−0.048:−0.002], p = 0.030) were independent predictors of follow-up ejection fraction. Patients with sACE2 in the upper tertile had a 4.4 fold increase in the incidence of adverse left ventricular remodeling (95% confidence interval: 1.3 to 15.2, p = 0.027). In conclusion, serum sACE2 activity rises in relation to infarct size, left ventricular systolic dysfunction and is associated with the occurrence of left ventricular remodeling. PMID:23630610

  7. Angiotensin-converting enzyme (ACE) gene insertion/deletion polymorphism is not a risk factor for hypertension in SLE nephritis.

    PubMed

    Negi, Vir S; Devaraju, Panneer; Gulati, Reena

    2015-09-01

    SLE is a systemic autoimmune disease with high prevalence of hypertension. Around 40-75 % of SLE patients develop nephritis, a major cause of hypertension and mortality. Angiotensin-converting enzyme (ACE) maintains the blood pressure and blood volume homeostasis. An insertion/deletion (I/D) polymorphism in intron 16 of ACE gene was reported to influence the development of hypertension, nephritis, and cardiovascular diseases in different ethnic populations. Despite compelling evidence for the high prevalence of hypertension in individuals with SLE, underlying factors for its development are not well studied. With this background, we analyzed the influence of ACE insertion/deletion polymorphism on susceptibility to SLE, development of nephritis and hypertension, other clinical features and autoantibody phenotype in South Indian SLE patients. Three hundred patients with SLE and 460 age and sex similar ethnicity matched individuals were included as patients and healthy controls, respectively. The ACE gene insertion/deletion polymorphism was analyzed by PCR. Insertion (I) and deletion (D) alleles were observed to be equally distributed among patients (57 and 43 %) and controls (59 and 41 %), respectively. The mutant (D) allele did not confer significant risk for SLE (II vs. ID: p = 0.4, OR 1.15, 95 % CI 0.8-1.6; II vs. DD: p = 0.34, OR 1.22, 95 % CI 0.8-1.85). There was no association of the ACE genotype or the allele with development of lupus nephritis (II vs. ID: p = 0.19, OR 1.41, 95 % CI 0.84-2.36; II vs. DD: p = 0.41, OR 0.74, 95 % CI 0.38-1.41) or hypertension (II vs. ID: p = 0.85, OR 0.9, 95 % CI 0.43-1.8; II vs. DD: p = 0.66, OR 1.217, 95 % CI 0.5-2.8). The presence of mutant allele (D) was not found to influence any clinical features or autoantibody phenotype. The insertion/deletion polymorphism of the ACE gene is not a genetic risk factor for SLE and does not influence development of hypertension or lupus nephritis in South Indian

  8. Synergism between paraoxonase Arg 192 and the angiotensin converting enzyme D allele is associated with severity of coronary artery disease.

    PubMed

    Vaisi-Raygani, Asad; Rahimi, Zohreh; Tavilani, Haidar; Vaisi-Raygani, Hadiss; Kiani, A; Aminian, M; Shakiba, E; Shakiba, Y; Pourmotabbed, Tayebeh

    2012-03-01

    We have previously shown that angiotensin-converting enzyme (ACE) gene D allele is an independent risk factor for early onset coronary artery disease (CAD). Little is known about the concomitant presence of the ACE gene D allele and paraoxonase (PON1) codon 192 arginine (Arg) on the severity of CAD. Regarding the high rate of CAD among Iranians the aim of present study was to examine the hypothesis of synergistic effects between ACE-D and PON1-Arg alleles on predisposition and the severity of CAD in our population. The PON1 192 and ACE insertion/deletion (I/D) genotypes were detected by PCR-RFLP and PCR, respectively in 414 individuals undergoing their first coronary angiography. Patients were placed into one of two groups: CAD and control without CAD or diabetes. We mentioned the synergistic effects of both genes and not ACE gene alone is a risk factor for CAD. We found that PON1 Arg 192 and ACE D allele act synergistically to increase the risk of CAD (OR 1.3, P = 0.044). Our results showed a significant correlation between the possession of both PON1 192 Arg and the ACE D allele and the extent of CAD in CAD patients and CAD subjects without diabetes, represented by the increased frequency of three-vessel disease with OR 2.7, P = 0.046; χ(2) = 4, P = 0.046 and OR 2.4, P = 0.051; χ(2) = 3.8, P = 0.051, respectively. We found that PON1 Arg 192 and ACE D alleles act synergistically to increase the risk of CAD in CAD patients and CAD subjects without diabetes from west of Iran, who have high frequency of three-vessel disease. Our data suggest that PON1 192 Arg and the ACE D allele in combination with each other can be important independent risk factor for severity of CAD in patients carrying both PON1 192 Arg and the ACE D allele in a west population of Iran.

  9. Decreased Risk of Radiation Pneumonitis With Incidental Concurrent Use of Angiotensin-Converting Enzyme Inhibitors and Thoracic Radiation Therapy

    SciTech Connect

    Kharofa, Jordan; Cohen, Eric P.; Tomic, Rade; Xiang Qun; Gore, Elizabeth

    2012-09-01

    Purpose: Angiotensin-converting enzyme (ACE) inhibitors have been shown to mitigate radiation-induced lung injury in preclinical models. The aim of this study was to evaluate whether ACE inhibitors decrease the risk of radiation pneumonitis in lung cancer patients receiving thoracic irradiation. Methods and Materials: Patients with Stage I through III small-cell and non-small-cell lung cancer treated definitively with radiation from 2004-2009 at the Clement J. Zablocki Veterans Affairs Medical Center were retrospectively reviewed. Acute pulmonary toxicity was quantified within 6 months of completion of treatment according to the Common Terminology Criteria for Adverse Events version 4. The use of ACE inhibitors, nonsteroidal anti-inflammatory drugs, inhaled glucocorticosteroids, statins, and angiotensin receptor blockers; dose-volume histogram parameters; and patient factors were assessed for association with Grade 2 or higher pneumonitis. Results: A total of 162 patients met the criteria for inclusion. The majority of patients had Stage III disease (64%) and received concurrent chemotherapy (61%). Sixty-two patients were identified as ACE inhibitor users (38%). All patients had acceptable radiation plans based on dose-volume histogram constraints (V20 [volume of lung receiving at least 20 Gy] {<=}37% and mean lung dose {<=}20 Gy) with the exception of 2 patients who did not meet both criteria. Grade 2 or higher pulmonary toxicity occurred in 12 patients (7.4%). The rate of Grade 2 or higher pneumonitis was lower in ACE inhibitor users vs. nonusers (2% vs. 11%, p = 0.032). Rates of Grade 2 or higher pneumonitis were significantly increased in patients aged greater than 70 years (16% vs. 2%, p = 0.005) or in whom V5 (volume of lung receiving at least 5 Gy) was 50% or greater (13% vs. 4%, p = 0.04). V10 (volume of lung receiving at least 10 Gy), V20, V30 (volume of lung receiving at least 30 Gy), and mean lung dose were not independently associated with Grade 2 or

  10. Cardiovascular status following combined angiotensin-converting enzyme and AT1 receptor inhibition in conscious spontaneously hypertensive rats.

    PubMed

    Duke, Lisa M; Paull, Jeremy R A; Widdop, Robert E

    2003-01-01

    1. Combined treatment of spontaneously hypertensive rats (SHR) with AT1 receptor antagonists and angiotensin-converting enzyme (ACE) inhibitors has been shown to reduce mean arterial pressure (MAP) more than monotherapy with either agent. The aims of the present study were to investigate the effects of chronic dual renin-angiotensin system (RAS) inhibition using non-hypotensive doses of the AT1 receptor antagonist candesartan cilexetil and the ACE inhibitor perindopril on cardiovascular function and structure. 2. Adult male SHR, aged 15 weeks, were divided into four groups: (i) candesartan cilexetil (0.5 mg/kg per day in drinking water); (ii) perindopril (0.3 mg/kg per day in drinking water); (iii) combined treatment (dual RAS inhibition); or (iv) the appropriate vehicle (0.1% ethanol/0.1% polyethylene glycol/1.5 mmol/l sodium bicarbonate dissolved in water for candesartan cilexetil; distilled water for perindopril). Systolic blood pressure was measured weekly using the tail-cuff method and urinary microalbuminuria was measured fortnightly. 3. After 4 weeks, rats were instrumented for intravenous drug administration and measurement of MAP. At this time, the cardiovascular effects of angiotensin (Ang) I and AngII (5-20 ng) and sodium nitroprusside (SNP) and acetylcholine (ACh; 1-5 micro g) were assessed. In addition, left ventricular : bodyweight and media : lumen ratios were determined as indices of cardiac and vascular hypertrophy, respectively. 4. Candesartan cilexetil and perindopril alone had minimal effect on MAP when measured both directly and indirectly, whereas direct MAP was significantly decreased in the combined treatment group (131 +/- 6 mmHg; P < 0.05) compared with the vehicle group (156 +/- 9 mmHg). Pressor responses to AngI were significantly decreased in all groups compared with the vehicle-treated group and pressor responses to AngII were significantly decreased in the candesartan cilexetil-treated (P < 0.01) and combined treatment groups (P < 0

  11. Angiotensin Converting Enzyme Inhibitors and Cognitive Decline in Older Adults with Hypertension: Results from the Cardiovascular Health Study

    PubMed Central

    Sink, Kaycee M.; Leng, Xiaoyan; Williamson, Jeff; Kritchevsky, Stephen B.; Yaffe, Kristine; Kuller, Lewis; Yasar, Sevil; Atkinson, Hal; Robbins, Mike; Psaty, Bruce; Goff, David C.

    2010-01-01

    Background Hypertension (HTN) is a risk factor for dementia and animal studies suggest that centrally active (cross the blood brain barrier) angiotensin converting enzyme (ACE) inhibitors may protect against dementia beyond HTN control. Methods Participants in the Cardiovascular Health Study cognition substudy (mean age 75 yrs) with treated HTN and no diagnosis of heart failure (n= 1054) were followed for a median of 6 years to determine whether cumulative exposure to ACE inhibitors (as a class and by central activity), compared to other antihypertensive agents, was associated with lower risk of incident dementia, cognitive decline (by the modified mini mental state exam, 3MSE), or incident disability in instrumental activities of daily living (IADL). Results Among 414 participants exposed to ACE inhibitors and 640 not, there were 158 cases of incident dementia. Compared to other anti-HTN drugs, there was no association between exposure to all ACE inhibitors and risk of dementia (HR 1.01, 95% CI 0.88–1.15), difference in 3MSE scores (−0.32 points/yr, p=0.15), or odds of IADL disability (OR (95% CI) 1.06 (0.99–1.14). Adjusted results were similar. However, centrally active ACE inhibitors were associated with 65% less decline in 3MSE scores per year of exposure (p= 0.01) and non-centrally active ACE inhibitors were associated with greater risk of incident dementia (adjusted HR 1.20 (1.00–1.43) per year of exposure) and greater odds of IADL disability (adjusted OR 1.16 (1.03–1.30) per year of exposure) compared to other anti-HTN drugs. Conclusions While ACE inhibitors as a class do not appear to be independently associated with dementia risk or cognitive decline in older hypertensive adults, there may be within class differences in regards to these outcomes. These results should be confirmed with an RCT of a centrally active ACE inhibitor in the prevention of cognitive decline and dementia. PMID:19597068

  12. Discovery of new angiotensin converting enzyme (ACE) inhibitors from medicinal plants to treat hypertension using an in vitro assay

    PubMed Central

    2013-01-01

    Background and purpose of the study Angiotensin converting enzyme (ACE) inhibitors plays a critical role in treating hypertension. The purpose of the present investigation was to evaluate ACE inhibition activity of 50 Iranian medicinal plants using an in vitro assay. Methods The ACE activity was evaluated by determining the hydrolysis rate of substrate, hippuryl-L-histidyl-L-leucine (HHL), using reverse phase high performance liquid chromatography (RP-HPLC). Total phenolic content and antioxidant activity were determined by Folin-Ciocalteu colorimetric method and DPPH radical scavenging assay respectively. Results Six extracts revealed > 50% ACE inhibition activity at 330 μg/ml concentration. They were Berberis integerrima Bunge. (Berberidaceae) (88.2 ± 1.7%), Crataegus microphylla C. Koch (Rosaceae) (80.9 ± 1.3%), Nymphaea alba L. (Nymphaeaceae) (66.3 ± 1.2%), Onopordon acanthium L. (Asteraceae) (80.2 ± 2.0%), Quercus infectoria G. Olivier. (Fagaceae) (93.9 ± 2.5%) and Rubus sp. (Rosaceae) (51.3 ± 1.0%). Q. infectoria possessed the highest total phenolic content with 7410 ± 101 mg gallic acid/100 g dry plant. Antioxidant activity of Q. infectoria (IC50 value 1.7 ± 0.03 μg/ml) was more than that of BHT (IC50 value of 10.3 ± 0.15 μg/ml) and Trolox (IC50 value of 3.2 ± 0.06 μg/ml) as the positive controls. Conclusions In this study, we introduced six medicinal plants with ACE inhibition activity. Despite the high ACE inhibition and antioxidant activity of Q. infectoria, due to its tannin content (tannins interfere in ACE activity), another plant, O. acanthium, which also had high ACE inhibition and antioxidant activity, but contained no tannin, could be utilized in further studies for isolation of active compounds. PMID:24359711

  13. The effect of enalapril (MK421), an angiotensin converting enzyme inhibitor, on the conscious pregnant ewe and her foetus.

    PubMed

    Broughton Pipkin, F; Wallace, C P

    1986-03-01

    The effects of enalapril, an angiotensin converting enzyme (ACE) inhibitor, on maternal and foetal blood pressure, heart rate and components of the renin-angiotensin-aldosterone system were studied in 9 chronically-cannulated pregnant ewes and their foetuses. Six ewes received 1 mg kg-1 enalapril i.v. while 3 were given 2 mg kg-1. Although the initial fall in blood pressure was slightly greater in the higher dose group, there was substantial overlap of data. The pressor response to angiotensin I, assessing ACE activity, was abolished within 10 min of administration, and did not recover during 3 h of observation. Maternal systolic and diastolic pressures reached a nadir 90 min after administration (P less than 0.001, P less than 0.002 respectively). The maximum tachycardia was seen at 60 min (P less than 0.05). The foetuses of the ewes given 1 mg kg-1 enalapril showed no change in systolic or diastolic blood pressure or heart rate. Those of the ewes given the higher dose showed late-onset hypotension, coincident with the lowest maternal blood pressures. Maternal plasma renin concentration (PRC) had risen significantly by 30 min (P less than 0.02), reaching a maximum at approximately 90 min. Maternal plasma angiotensin II and aldosterone concentrations both fell initially (P less than 0.05) but were almost at basal levels by the end of the experiment. Foetal plasma renin, angiotensin II and aldosterone concentrations were unchanged throughout the experiment. Peak values of enaprilic acid, the active principle, were recorded in maternal plasma 65-90 min after administration of 1 mg kg-1, and 25-30 min after the administration of 2 mg kg-1. A trace amount of the active principle was recorded in the foetal plasma of one lamb, whose mother had been given the higher dose. None was recorded in the plasma from three other lambs. Maternal plasma ACE concentrations fell by an average of 84%; in 4 of the 6 ewes in which concentrations were measured they were undetectable after

  14. Association of Urinary N-Domain Angiotensin I-Converting Enzyme with Plasma Inflammatory Markers and Endothelial Function

    PubMed Central

    Fernandes, Fernanda B; Plavnik, Frida L; Teixeira, Andressa MS; Christofalo, Dejaldo MJ; Ajzen, Sergio A; Higa, Elisa MS; Ronchi, Fernanda A; Sesso, Ricardo CC; Casarini, Dulce E

    2008-01-01

    The aim of this study was to investigate the association between urinary 90 kDa N-domain Angiotensin I-converting enzyme (ACE) form with C-reactive protein (CRP) and homocysteine plasma levels (Hcy), urinary nitric oxide (NOu), and endothelial function (EF) in normotensive subjects. Forty healthy subjects were evaluated through brachial Doppler US to test the response to reactive hyperemia and a panel of blood tests to determine CRP and Hcy levels, NOu, and urinary ACE. They were divided into groups according to the presence (ACE90+) or absence (ACE90–) of the 90 kDa ACE, the presence (FH+) or absence (FH–) of family history of hypertension, and the presence or absence of these two variables FH+/ACE90+ and FH–/ACE90–. We found an impaired endothelial dilatation in subjects who presented the 90 kDa N-domain ACE as follows: 11.4% ± 5.3% in ACE90+ compared with 17.6% ± 7.1% in ACE90– group and 12.4% ± 5.6% in FH+/ACE90+ compared with 17.7% ± 6.2% in FH–/ACE90– group, P < 0.05. Hcy and CRP levels were statistically significantly lower in FH+/ACE90+ than in FH–/ACE90– group, as follows: 10.0 ± 2.3 μM compared with 12.7 ± 1.5 μM, and 1.3 ± 1.8 mg/L compared with 3.6 ± 2.0 mg/L, respectively. A correlation between flow-mediated dilatation (FMD) and CRP, Hcy, and NOu levels was not found. Our study suggests a reduction in the basal NO production confirmed by NOu analysis in subjects with the 90 kDa N-domain ACE isoform alone or associated with a family history of hypertension. Our data suggest that the presence of the 90 kDa N-domain ACE itself may have a negative impact on flow-mediated dilatation stimulated by reactive hyperemia. PMID:18475311

  15. Debate: angiotensin-converting enzyme inhibitors versus angiotensin II receptor blockers--a gap in evidence-based medicine.

    PubMed

    Ball, Stephen G; White, William B

    2003-05-22

    In this article, 2 leading physicians debate the strength of outcome data on the efficacy of angiotensin-converting enzyme (ACE) inhibitors versus angiotensin II receptor blockers (ARBs) for reducing the incidence of cardiovascular, cerebrovascular, and renovascular events. Dr. Stephen G. Ball notes that the efficacy of ACE inhibitors for reducing the risk for myocardial infarction independent of their effects on blood pressure is controversial. In the Heart Outcomes Prevention Evaluation (HOPE) study, ramipril treatment in high-risk patients was associated with a 20% reduction in the risk for myocardial infarction; mean reduction in blood pressure was 3 mm Hg for systolic blood pressure and 1 mm Hg for diastolic blood pressure. The HOPE investigators propose that the 20% reduction was much greater than would be expected based on the observed blood pressure reduction. However, a meta-regression analysis of blood pressure reduction in >20 antihypertensive therapy outcome trials found that the reduction in myocardial infarction risk with ramipril observed in HOPE was consistent with the modest blood pressure reduction seen with that agent. Nevertheless, there are convincing data for prevention of myocardial infarction with ACE inhibitors in patients with heart failure, including those with heart failure after myocardial infarction, as well as supportive evidence from studies in patients with diabetes mellitus and concomitant hypertension. On the other hand, Dr. William B. White takes the position that ARBs are well-tolerated antihypertensive agents that specifically antagonize the angiotensin II type 1 (AT(1)) receptor and provide a more complete block of the pathologic effects of angiotensin II-which are mediated via the AT(1) receptor-than ACE inhibitors. The Evaluation of Losartan in the Elderly (ELITE) II study and the Valsartan Heart Failure Trial (ValHeFT) suggest that ARBs reduce the risk for mortality in patients with congestive heart failure. The Losartan

  16. Voltage-programming-based capillary gel electrophoresis for the fast detection of angiotensin-converting enzyme insertion/deletion polymorphism with high sensitivity.

    PubMed

    Woo, Nain; Kim, Su-Kang; Kang, Seong Ho

    2016-08-01

    A voltage-programming-based capillary gel electrophoresis method with a laser-induced fluorescence detector was developed for the fast and highly sensitive detection of DNA molecules related to angiotensin-converting enzyme insertion/deletion polymorphism, which has been reported to influence predisposition to various diseases such as cardiovascular disease, high blood pressure, myocardial infarction, and Alzheimer's disease. Various voltage programs were investigated for fast detection of specific DNA molecules of angiotensin-converting enzyme insertion/deletion polymorphism as a function of migration time and separation efficiency to establish the effect of voltage strength to resolution. Finally, the amplified products of the angiotensin-converting enzyme insertion/deletion polymorphism (190 and 490 bp DNA) were analyzed in 3.2 min without losing resolution under optimum voltage programming conditions, which were at least 75 times faster than conventional slab gel electrophoresis. In addition, the capillary gel electrophoresis method also successfully applied to the analysis of real human blood samples, although no polymorphism genes were detected by slab gel electrophoresis. Consequently, the developed voltage-programming capillary gel electrophoresis method with laser-induced fluorescence detection is an effective, rapid analysis technique for highly sensitive detection of disease-related specific DNA molecules.

  17. Effect of Flavourzyme(®) on Angiotensin-Converting Enzyme Inhibitory Peptides Formed in Skim Milk and Whey Protein Concentrate during Fermentation by Lactobacillus helveticus.

    PubMed

    Ahtesh, Fatah; Stojanovska, Lily; Shah, Nagendra; Mishra, Vijay Kumar

    2016-01-01

    Angiotensin-converting enzyme inhibitory (ACE-I) activity as affected by Lactobacillus helveticus strains (881315, 881188, 880474, and 880953), and supplementation with a proteolytic enzyme was studied. Reconstituted skim milk (12% RSM) or whey protein concentrate (4% WPC), with and without Flavourzyme(®) (0.14% w/w), were fermented with 4 different L. helveticus strains at 37 °C for 0, 4, 8, and 12 h. Proteolytic and in vitro ACE-I activities, and growth were significantly affected (P < 0.05) by strains, media, and with enzyme supplementation. RSM supported higher growth and produced higher proteolysis and ACE-I compared to WPC without enzyme supplementation. The strains L. helveticus 881315 and 881188 were able to increase ACE-I to >80% after 8 h of fermentation when combined with Flavourzyme(®) in RSM compared to the same strains without enzyme supplementation. Supplementation of media by Flavourzyme(®) was beneficial in increasing ACE-I peptides in both media. The best media to release more ACE-I peptides was RSM with enzyme supplementation. The L. helveticus 881315 outperformed all strains as indicated by highest proteolytic and ACE-I activities.

  18. Local corticosterone production and angiotensin-I converting enzyme shedding in a mouse model of intestinal inflammation

    PubMed Central

    Salmenkari, Hanne; Issakainen, Tomi; Vapaatalo, Heikki; Korpela, Riitta

    2015-01-01

    AIM: To investigate local corticosterone production and angiotensin-I converting enzyme (ACE) protein expression and their interaction in healthy and inflamed intestine. METHODS: Acute intestinal inflammation was induced to six weeks old male Balb/c mice by administration of either 3% or 5% dextran sodium sulfate (DSS) in drinking water for 7 d (n = 12 in each group). Healthy controls (n = 12) were given tap water. Corticosterone production and ACE protein shedding were measured from ex vivo incubates of the small and large intestine using EIA and ELISA, respectively. Morphological changes of the intestinal wall were assessed in hematoxylin-eosin stained tissue preparations of jejunum and distal colon. Effects of angiotensin II, captopril and metyrapone on corticosterone production was assessed by incubating pieces of small intestine of healthy mice in the presence of 0.1, 1 or 10 μmol/L angiotensin II, 1, 10 or 100 μmol/L captopril or 1, 10 or 100 μmol/L metyrapone solutions and measuring corticosterone released to the incubation buffer after 90 min (n = 5 in each group). RESULTS: Both concentrations of DSS induced inflammation and morphological changes in large intestines but not in small intestines. Changes were observed as distortions of the crypt structure, mucosal erosion, immune cell infiltration to the mucosa and submucosal edema. Ex vivo corticosterone production (2.9 ± 1.0 ng/mL vs 2.0 ± 0.8 ng/mL, P = 0.034) and ACE shedding (269.2 ± 97.1 ng/mL vs 175.7 ± 52.2 ng/mL, P = 0.016) were increased in small intestines in 3% DSS group compared to the controls. In large intestine, corticosterone production was increased compared to the controls in both 3% DSS (229 ± 81 pg/mL vs 158 ± 30 pg/mL, P = 0.017) and 5% DSS groups (366 ± 163 pg/mL vs 158 ± 30 pg/mL, P = 0.002). Large intestine ACE shedding was increased in 5% DSS group (41.5 ± 9.0 ng/mL vs 20.9 ± 5.2 ng/mL, P = 0.034). Angiotensin II treatment augmented corticosterone production in small

  19. An intact SAM-dependent methyltransferase fold is encoded by the human endothelin-converting enzyme-2 gene

    SciTech Connect

    Tempel, W.; Wu, H.; Dombrovsky, L.; Zeng, H.; Loppnau, P.; Zhu, H.; Plotnikov, A.N.; Bochkarev, A.

    2010-08-17

    A recent survey of protein expression patterns in patients with Alzheimer's disease (AD) has identified ece2 (chromosome: 3; Locations: 3q27.1) as the most significantly downregulated gene within the tested group. ece2 encodes endothelin-converting enzyme ECE2, a metalloprotease with a role in neuropeptide processing. Deficiency in the highly homologous ECE1 has earlier been linked to increased levels of AD-related {beta}-amyloid peptide in mice, consistent with a role for ECE in the degradation of that peptide. Initially, ECE2 was presumed to resemble ECE1, in that it comprises a single transmembrane region of {approx}20 residues flanked by a small amino-terminal cytosolic segment and a carboxy-terminal lumenar peptidase domain. The carboxy-terminal domain has significant sequence similarity to both neutral endopeptidase, for which an X-ray structure has been determined, and Kell blood group protein. After their initial discovery, multiple isoforms of ECE1 and ECE2 were discovered, generated by alternative splicing of multiple exons. The originally described ece2 transcript, RefSeq NM{_}174046, contains the amino-terminal cytosolic portion followed by the transmembrane region and peptidase domain (Fig. 1, isoform B). Another ece2 transcript, available from the Mammalian Gene Collection under MGC2408 (Fig. 1, isoform C), RefSeq accession NM{_}032331, is predicted to be translated into a 255 residue peptide with low but detectable sequence similarity to known S-adenosyl-L-methionine (SAM)-dependent methyltransferases (SAM-MTs), such as the hypothetical protein TT1324 from Thermus thermophilis, PDB code 2GS9, which shares 30% amino acid sequence identity with ECE2 over 138 residues of the sequence. Intriguingly, another 'elongated' ece2 transcript (Fig. 1, isoform A) (RefSeq NM{_}014693) contains an amino-terminal portion of the putative SAM-MT domain, the transmembrane domain, and the protease domain. This suggests the possibility for coexistence of the putative SAM

  20. A focused parameter update: hereditary angioedema, acquired C1 inhibitor deficiency, and angiotensin-converting enzyme inhibitor-associated angioedema.

    PubMed

    Zuraw, Bruce L; Bernstein, Jonathan A; Lang, David M; Craig, Timothy; Dreyfus, David; Hsieh, Fred; Khan, David; Sheikh, Javed; Weldon, David; Bernstein, David I; Blessing-Moore, Joann; Cox, Linda; Nicklas, Richard A; Oppenheimer, John; Portnoy, Jay M; Randolph, Christopher R; Schuller, Diane E; Spector, Sheldon L; Tilles, Stephen A; Wallace, Dana

    2013-06-01

    These parameters were developed by the Joint Task Force on Practice Parameters (JTFPP), representing the American Academy of Allergy, Asthma & Immunology (AAAAI); the American College of Allergy, Asthma & Immunology (ACAAI); and the Joint Council of Allergy, Asthma and Immunology. The AAAAI and the ACAAI have jointly accepted responsibility for establishing "A focused parameter update: Hereditary angioedema, acquired C1 inhibitor deficiency, and angiotensin-converting enzyme inhibitor-associated angioedema." This is a complete and comprehensive document at the current time. The medical environment is a changing environment, and not all recommendations will be appropriate for all patients. Because this document incorporated the efforts of many participants, no single individual, including those who served on the JTFPP, is authorized to provide an official AAAAI or ACAAI interpretation of these practice parameters. Any request for information about or an interpretation of these practice parameters by the AAAAI or ACAAI should be directed to the Executive Offices of the AAAAI, the ACAAI, and the Joint Council of Allergy, Asthma and Immunology. The Joint Task Force on Practice Parameters understands that the cost of diagnostic tests and therapeutic agents is an important concern that might appropriately influence the work-up and treatment chosen for a given patient. The JTFPP recognizes that the emphasis of our primary recommendations regarding a medication might vary, for example, depending on third-party payer issues and product patent expiration dates. However, because the cost of a given test or agent is so widely variable and there is a paucity of pharmacoeconomic data, the JTFPP generally does not consider cost when formulating practice parameter recommendations. In some instances the cost benefit of an intervention is considered relevant, and commentary might be provided. These parameters are not designed for use by pharmaceutical companies in drug promotion

  1. Angiotensin II receptor antagonists and heart failure: angiotensin-converting-enzyme inhibitors remain the first-line option.

    PubMed

    2005-10-01

    (1) Some angiotensin-converting-enzyme inhibitors (ACE inhibitors) reduce mortality in patients with heart failure (captopril, enalapril, ramipril and trandolapril), and in patients with recent myocardial infarction and heart failure or marked left ventricular dysfunction (captopril, ramipril and trandolapril). (2) Angiotensin II receptor antagonists, otherwise known as angiotensin receptor blockers, have haemodynamic effects similar to ACE inhibitors, but differ in their mechanism of action and certain adverse effects. (3) Five clinical trials have evaluated angiotensin II receptor antagonists (candesartan, losartan and valsartan) in terms of their effect on mortality and on the risk of clinical deterioration in patients with symptomatic heart failure, but without severe renal failure, hyperkalemia or hypotension. In these trials, candesartan and valsartan were used at much higher doses than those recommended for the treatment of arterial hypertension. (4) In patients with heart failure who were not taking an angiotensin II receptor antagonist or an ACE inhibitor at enrollment, no significant difference was found between losartan and captopril in terms of mortality or the risk of clinical deterioration. (5) In patients with heart failure who had stopped taking an ACE inhibitor because of adverse effects, candesartan had no effect on mortality as compared with placebo, but it did reduce the risk of clinical deterioration (3 fewer hospitalisations per year per 100 patients). However, candesartan was associated with adverse effects such as renal failure and hyperkalemia, especially in patients who had experienced these same adverse effects while taking an ACE inhibitor. (6) In patients with heart failure who were already taking an ACE inhibitor, adjunctive candesartan or valsartan treatment did not influence mortality in comparison to the addition of a placebo. Adding candesartan or valsartan reduced the risk of hospitalisation (between 1 and 3 fewer hospitalisations

  2. Effects of angiotensin-converting enzyme inhibition on altered renal hemodynamics induced by low protein diet in the rat.

    PubMed Central

    Fernández-Repollet, E; Tapia, E; Martínez-Maldonado, M

    1987-01-01

    We assessed the role of angiotensin II in mediating the alterations in renal hemodynamics known to result from low protein feeding to normal rats by examining the effect of the angiotensin-converting enzyme (ACE) inhibitor captopril. 2 wk of low protein (6% casein) diet resulted in decreased glomerular filtration rate (normal protein [NP], 1.82 +/- 0.17 vs. low protein [LP], 0.76 +/- 0.01 ml/min; P less than 0.05) and renal plasma flow (NP, 6.7 +/- 0.2 vs. LP, 3.3 +/- 0.3 ml/min; P less than 0.05); renal vascular resistance rose (NP, 8.7 +/- 0.4 vs. LP, 19.8 +/- 1.4 dyn . s per cm5; P less than 0.05). These changes were accompanied by a significant decrease in plasma renin activity (NP, 7.0 +/- 0.7 vs. LP, 4.4 +/- 0.8 ng A I/ml per h; P less than 0.05), plasma aldosterone concentration (NP, 7.0 +/- 0.6 vs. LP, 4.1 +/- 0.7 ng/dl; P less than 0.05), and urinary PGE2 excretion (NP, 3,120 +/- 511 vs. LP, 648 +/- 95 pg/mgCr; P less than 0.05); by contrast renal renin content was significantly increased (NP, 2,587 +/- 273 vs. LP, 7,032 +/- 654 ng A I/mg protein; P less than 0.05). Treatment with captopril (30 mg/kg per d) raised glomerular filtration rate (GFR; LP + capt, 1.6 +/- 0.2 ml/min) and renal plasma flow (RPF; LP + capt, 6.7 +/- 0.7 ml/min), and reduced renal vascular resistance (LP + capt, 9.2 +/- 0.5 dyn/s per cm5) in low protein-fed animals. These values were not different from those measured in untreated and captopril-treated rats fed a normal (23%) protein diet. There were no changes in systemic mean arterial pressure in any group of rats. These data provide evidence that intrarenal angiotensin II mediates the changes in intrarenal hemodynamics induced by protein deprivation. The effects of low protein feeding may be partly potentiated by the reduction in PGE2 synthesis. However, the normalization of GFR and RPF in view of only modest increases in PGE2 excretion after captopril (LP, 648 +/- 95 vs. LP + capt, 1,131 +/- 82 pg/mgCr; P less than 0.05) suggests

  3. Screening of inhibitors of angiotensin-converting enzyme (ACE) employing high performance liquid chromatography-electrospray ionization triple quadrupole mass spectrometry (HPLC-ESI-QqQ-MS).

    PubMed

    Musharraf, Syed Ghulam; Bhatti, Muhammad Salman; Choudhary, Muhammad Iqbal; Rahman, Atta-Ur

    2017-04-01

    Angiotensin-converting enzyme (ACE) plays a key role in regulating blood pressure in the body by converting the angiotensin I (AI) into angiotensin II (AII). Angiotensin II is a potent vaso-active peptide that causes arterioles to constrict, resulting in increased blood pressure. A rapid and sensitive method for the identification of inhibitors of ACE was developed, and optimized employing HPLC-ESI-QqQ-MS. In this assay, angiotensin I substrate was converted into the product angiotensin II with the catalytic action of ACE. A calibration curve for depleting concentration of angiotensin I was developed and linearity of R(2)=0.999 with a remarkably low concentration of substrate range 20-200nM. The limit of detection and quantification of angiotensin I was found to be 1.93 and 5.84nM, respectively. The enzymatic reaction was optimized for incubation time, concentration, and volume of enzyme and substrate. All reactions were performed at 37°C at pH7.5 with standard incubation time of 20min. Two standard inhibitors, Captopril and Lisinopril, were checked through the newly developed method for their inhibitory potential, and their IC50 values were found to be 3.969 and 0.852μM, respectively. Reproducibility and precision analysis of different experiments showed <9.9% RSD. The developed method can be used for the identification of new ACE inhibitors.

  4. Comparative study of Mg/Al- and Zn/Al-layered double hydroxide-perindopril erbumine nanocomposites for inhibition of angiotensin-converting enzyme

    PubMed Central

    Hussein Al Ali, Samer Hasan; Al-Qubaisi, Mothanna; Hussein, Mohd Zobir; Ismail, Maznah; Zainal, Zulkarnain; Hakim, Muhammad Nazrul

    2012-01-01

    The intercalation of a drug active, perindopril, into Mg/Al-layered double hydroxide for the formation of a new nanocomposite, PMAE, was accomplished using a simple ion exchange technique. A relatively high loading percentage of perindopril of about 36.5% (w/w) indicates that intercalation of the active took place in the Mg/Al inorganic interlayer. Intercalation was further supported by Fourier transform infrared spectroscopy, and thermal analysis shows markedly enhanced thermal stability of the active. The release of perindopril from the nanocomposite occurred in a controlled manner governed by pseudo-second order kinetics. MTT assay showed no cytotoxicity effects from either Mg/Al-layered double hydroxide or its nanocomposite, PMAE. Mg/Al-layered double hydroxide showed angiotensin-converting enzyme inhibitory activity, with 5.6% inhibition after 90 minutes of incubation. On incubation of angiotensin-converting enzyme with 0.5 μg/mL of the PMAE nanocomposite, inhibition of the enzyme increased from 56.6% to 70.6% at 30 and 90 minutes, respectively. These results are comparable with data reported in the literature for Zn/Al-perindopril. PMID:22904631

  5. Comparative study of Mg/Al- and Zn/Al-layered double hydroxide-perindopril erbumine nanocomposites for inhibition of angiotensin-converting enzyme.

    PubMed

    Hussein Al Ali, Samer Hasan; Al-Qubaisi, Mothanna; Hussein, Mohd Zobir; Ismail, Maznah; Zainal, Zulkarnain; Hakim, Muhammad Nazrul

    2012-01-01

    The intercalation of a drug active, perindopril, into Mg/Al-layered double hydroxide for the formation of a new nanocomposite, PMAE, was accomplished using a simple ion exchange technique. A relatively high loading percentage of perindopril of about 36.5% (w/w) indicates that intercalation of the active took place in the Mg/Al inorganic interlayer. Intercalation was further supported by Fourier transform infrared spectroscopy, and thermal analysis shows markedly enhanced thermal stability of the active. The release of perindopril from the nanocomposite occurred in a controlled manner governed by pseudo-second order kinetics. MTT assay showed no cytotoxicity effects from either Mg/Al-layered double hydroxide or its nanocomposite, PMAE. Mg/Al-layered double hydroxide showed angiotensin-converting enzyme inhibitory activity, with 5.6% inhibition after 90 minutes of incubation. On incubation of angiotensin-converting enzyme with 0.5 μg/mL of the PMAE nanocomposite, inhibition of the enzyme increased from 56.6% to 70.6% at 30 and 90 minutes, respectively. These results are comparable with data reported in the literature for Zn/Al-perindopril.

  6. Selective restoration of male fertility in mice lacking angiotensin-converting enzymes by sperm-specific expression of the testicular isozyme.

    PubMed Central

    Ramaraj, P; Kessler, S P; Colmenares, C; Sen, G C

    1998-01-01

    Although angiotensin-converting enzyme (ACE) has been studied primarily in the context of its role in blood pressure regulation, this widely distributed enzyme has many other physiological functions. The ACE gene encodes two isozymes. The somatic isozyme is expressed in many tissues, including vascular endothelial cells, renal epithelial cells, and testicular Leydig cells, whereas the testicular or germinal angiotensin-converting enzyme is expressed only in sperm. The ACE gene knockout mice lack both isozymes and they exhibit low blood pressure, kidney dysfunctions, and male infertility. Here, we report the use of a sperm-specific promoter and interbreeding of transgenic and gene knockout mice for generating a mouse strain that expressed ACE only in sperm. The experimental mice maintained the kidney defects of ACE-/- mice, but unlike the knockout strain, the males were fertile. Thus, we established that the role of ACE in male fertility is completely dependent on its exclusive expression in sperm. Our study clearly demonstrated how transgenic and knockout techniques can be combined for ascribing a specific physiological function to the expression of a multifunctional protein in a given tissue. PMID:9664078

  7. When Nothing Else Works: Fresh Frozen Plasma in the Treatment of Progressive, Refractory Angiotensin-Converting Enzyme Inhibitor-Induced Angioedema.

    PubMed

    Chaaya, Gerard; Afridi, Faraz; Faiz, Arfa; Ashraf, Ali; Ali, Mahrukh; Castiglioni, Analia

    2017-01-11

    Angioedema is a severe form of an allergic reaction characterized by the localized edematous swelling of the dermis and subcutaneous tissues. Angiotensin-converting enzyme inhibitor-induced angioedema (ACEI-IA) is an allergic reaction that can be severe in some cases requiring advanced management measures. Fresh frozen plasma has been used off-labeled in some case reports to improve and to prevent worsening of the angioedema in a few cases of ACEI-IA. We are reporting this case to increase the awareness of physicians and to widen their therapeutic options when encountering this clinically significant condition.

  8. Determining the Enzymatic Activity of Angiotensin-Converting Enzyme 2 (ACE2) in Brain Tissue and Cerebrospinal Fluid Using a Quenched Fluorescent Substrate.

    PubMed

    Sriramula, Srinivas; Pedersen, Kim Brint; Xia, Huijing; Lazartigues, Eric

    2017-01-01

    Angiotensin-converting enzyme 2 (ACE2) is a component of the renin-angiotensin system (RAS) which plays an important role in the regulation of blood pressure and volume homeostasis. Accumulating evidence shows alterations in ACE2 expression and activity in several hypertensive animal models, as well as in patients with hypertension. In order to assess the role of brain ACE2 in hypertension, a specific ACE2 assay is required. Based on a quenched fluorescent substrate, we describe an easy-to-use method for determining ACE2 activity in brain tissue and cerebrospinal fluid. The method can further be adapted for other tissues, plasma, cell extracts, and cell culture supernatants.

  9. When Nothing Else Works: Fresh Frozen Plasma in the Treatment of Progressive, Refractory Angiotensin-Converting Enzyme Inhibitor–Induced Angioedema

    PubMed Central

    Afridi, Faraz; Faiz, Arfa; Ashraf, Ali; Ali, Mahrukh; Castiglioni, Analia

    2017-01-01

    Angioedema is a severe form of an allergic reaction characterized by the localized edematous swelling of the dermis and subcutaneous tissues. Angiotensin-converting enzyme inhibitor-induced angioedema (ACEI-IA) is an allergic reaction that can be severe in some cases requiring advanced management measures. Fresh frozen plasma has been used off-labeled in some case reports to improve and to prevent worsening of the angioedema in a few cases of ACEI-IA. We are reporting this case to increase the awareness of physicians and to widen their therapeutic options when encountering this clinically significant condition.  PMID:28191376

  10. Renin-angiotensin-aldosterone system inhibition: overview of the therapeutic use of angiotensin-converting enzyme inhibitors, angiotensin receptor blockers, mineralocorticoid receptor antagonists, and direct renin inhibitors.

    PubMed

    Mercier, Kelly; Smith, Holly; Biederman, Jason

    2014-12-01

    Angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) therapy in hypertensive diabetic patients with macroalbuminuria, microalbuminuria, or normoalbuminuria has been repeatedly shown to improve cardiovascular mortality and reduce the decline in glomerular filtration rate. Renin-angiotensin-aldosterone system (RAAS) blockade in normotensive diabetic patients with normoalbuminuria or microalbuminuria cannot be advocated at present. Dual RAAS inhibition with ACE inhibitors plus ARBs or ACE inhibitors plus direct renin inhibitors has failed to improve cardiovascular or renal outcomes but has predisposed patients to serious adverse events.

  11. [STUDIES IN VITRO INHIBITION OF THE ANGIOTENSIN-CONVERTING ENZYME-I, HYPOTENSIVE AND ANTIHYPERTENSIVE EFFECTS OF PEPTIDE FRACTIONS OF V. UNGUICULATA].

    PubMed

    Cú-Cañetas, Trinidad; Betancur Ancona, David; Gallegos Tintoré, Santiago; Sandoval Peraza, Mukthar; Chel Guerrero, Luis

    2015-11-01

    Inhibition of angiotensin-converting enzyme I (ACE-I) in vitro and in vivo from peptide fractions by enzymatic hydrolysis of the Vigna unguiculata protein concentrate was evaluated. Hydrolysis was done with Pepsin-Pancreatin and Flavourzima in two separate systems. The resulting hidrolysates were ultrafiltrated to obtain fractions with different molecular weight. The fractions with better inhibition Flavourzima were size > 1 kDa (> 1 kDa-F) and < 1 kDa (< 1 kDa-F), with an IC50 of 1222.84 and 1098.6 μg/ml respectively. Pepsin-Pancreatin fraction.

  12. Porcine pulmonary angiotensin I-converting enzyme--biochemical characterization and spatial arrangement of the N- and C-domains by three-dimensional electron microscopic reconstruction.

    PubMed

    Chen, Hui-Ling; Lünsdorf, Heinrich; Hecht, Hans-Jürgen; Tsai, Hsin

    2010-08-01

    The somatic angiotensin I-converting enzyme (sACE; peptidyl-dipeptidase A; EC 3.4.15.1) was isolated from pig lung and purified to homogeneity. The purified enzyme has a molecular mass of about 180 kDa. Upon proteolytic cleavage, two approximately 90 kDa fragments were obtained and identified by amino-terminal sequence analysis as the N- and C-domains of sACE. Both purified domains were shown to be catalytically active. A 2.3 nm resolution model of sACE was obtained by three-dimensional electron microscopic reconstruction of negatively stained sACE particles, based on atomic X-ray data fitting. Our model shows for the first time the relative orientation of the sACE catalytically active domains and their spatial distance.

  13. The cancer preventative agent resveratrol is converted to the anticancer agent piceatannol by the cytochrome P450 enzyme CYP1B1

    PubMed Central

    Potter, G A; Patterson, L H; Wanogho, E; Perry, P J; Butler, P C; Ijaz, T; Ruparelia, K C; Lamb, J H; Farmer, P B; Stanley, L A; Burke, M D

    2002-01-01

    Resveratrol is a cancer preventative agent that is found in red wine. Piceatannol is a closely related stilbene that has antileukaemic activity and is also a tyrosine kinase inhibitor. Piceatannol differs from resveratrol by having an additional aromatic hydroxy group. The enzyme CYP1B1 is overexpressed in a wide variety of human tumours and catalyses aromatic hydroxylation reactions. We report here that the cancer preventative agent resveratrol undergoes metabolism by the cytochrome P450 enzyme CYP1B1 to give a metabolite which has been identified as the known antileukaemic agent piceatannol. The metabolite was identified by high performance liquid chromatography analysis using fluorescence detection and the identity of the metabolite was further confirmed by derivatisation followed by gas chromatography–mass spectrometry studies using authentic piceatannol for comparison. This observation provides a novel explanation for the cancer preventative properties of resveratrol. It demonstrates that a natural dietary cancer preventative agent can be converted to a compound with known anticancer activity by an enzyme that is found in human tumours. Importantly this result gives insight into the functional role of CYP1B1 and provides evidence for the concept that CYP1B1 in tumours may be functioning as a growth suppressor enzyme. British Journal of Cancer (2002) 86, 774–778. DOI: 10.1038/sj/bjc/6600197 www.bjcancer.com © 2002 Cancer Research UK PMID:11875742

  14. Mice deficient in Endothelin-Converting Enzyme-2 exhibit abnormal responses to morphine and altered peptide levels in the spinal cord

    PubMed Central

    Miller, L.K.; Hou, X.; Rodriguiz, R.M.; Gagnidze, K.; Sweedler, J. V.; Wetsel, W.C.; Devi, L.A.

    2011-01-01

    An increasing body of evidence suggests that Endothelin-converting enzyme-2 (ECE-2) is a non-classical neuropeptide processing enzyme. Similar to other neuropeptide processing enzymes, ECE-2 exhibits restricted neuroendocrine distribution, intracellular localization, and an acidic pH optimum. However, unlike classical neuropeptide processing enzymes, ECE-2 exhibits a non-classical cleavage site preference for aliphatic and aromatic residues. We previously reported that ECE-2 cleaves a number of neuropeptides at non-classical sites in vitro; however its role in peptide processing in vivo is poorly understood. Given the recognized roles of neuropeptides in pain and opiate responses, we hypothesized that ECE-2 knockout (KO) mice might show altered pain and morphine responses compared to wild-type (WT) mice. We find that ECE-2 KO mice show decreased response to a single injection of morphine in hot-plate and tail-flick tests. ECE-2 KO mice also show more rapid development of tolerance with prolonged morphine treatment and fewer signs of naloxone-precipitated withdrawal. Peptidomic analyses revealed changes in the levels of a number of spinal cord peptides in ECE-2 KO as compared to WT mice. Taken together, our findings suggest a role for ECE-2 in the non-classical processing of spinal cord peptides and morphine responses; however, the precise mechanisms through which ECE-2 influences morphine tolerance and withdrawal remain unclear. PMID:21972895

  15. Angiotensin-converting enzyme (ACE) dimerization is the initial step in the ACE inhibitor-induced ACE signaling cascade in endothelial cells.

    PubMed

    Kohlstedt, Karin; Gershome, Cynthia; Friedrich, Matthias; Müller-Esterl, Werner; Alhenc-Gelas, François; Busse, Rudi; Fleming, Ingrid

    2006-05-01

    The binding of angiotensin-converting enzyme (ACE) inhibitors to ACE initiates a signaling cascade that involves the phosphorylation of the enzyme on Ser1270 as well as activation of the c-Jun NH2-terminal kinase (JNK) and leads to alterations in gene expression. To clarify how ACE inhibitors activate this pathway, we determined their effect on the ability of the enzyme to dimerize and the role of ACE dimerization in the initiation of the ACE signaling cascade. In endothelial cells, ACE was detected as a monomer as well as a dimer in native gel electrophoresis and dimerization/oligomerization was confirmed using the split-ubiquitin assay in yeast. ACE inhibitors elicited a rapid, concentration-dependent increase in the dimer/monomer ratio that correlated with that of the ACE inhibitorinduced phosphorylation of ACE. Cell treatment with galactose and glucose to prevent the putative lectin-mediated self-association of ACE or with specific antibodies shielding the N terminus of ACE failed to affect either the basal or the ACE inhibitor-induced dimerization of the enzyme. In ACE-expressing Chinese hamster ovary cells, ACE inhibitors elicited ACE dimerization and phosphorylation as well as the activation of JNK with similar kinetics to those observed in endothelial cells. However, these effects were prevented by the mutation of the essential Zn2+-complexing histidines in the C-terminal active site of the enzyme. Mutation of the N-terminal active site of ACE was without effect. Together, our data suggest that ACE inhibitors can initiate the ACE signaling pathway by inducing ACE dimerization, most probably via the C-terminal active site of the enzyme.

  16. In vitro angiotensin I converting enzyme inhibition by a peptide isolated from Chiropsalmus quadrigatus Haeckel (box jellyfish) venom hydrolysate.

    PubMed

    So, Pamela Berilyn T; Rubio, Peter; Lirio, Stephen; Macabeo, Allan Patrick; Huang, Hsi-Ya; Corpuz, Mary Jho-Anne T; Villaflores, Oliver B

    2016-09-01

    The anti-angiotensin I converting enzyme activity of box jellyfish, Chiropsalmus quadrigatus Haeckel venom hydrolysate was studied. The venom extract was obtained by centrifugation and ultrasonication. Protein concentration of 12.99 μg/mL was determined using Bradford assay. The pepsin and papain hydrolysate was tested for its toxicity by Limit test following the OECD Guideline 425 using 5 female Sprague-Dawley rats. Results showed that the hydrolysate is nontoxic with an LD50 above 2000 mg/kg. In vitro angiotensin I converting enzyme (ACE) inhibitory activity was determined using ACE kit-WST. Isolation of ACE inhibitory peptides using column chromatography with SP-Sephadex G-25 yielded 8 pooled fractions with fraction 3 (86.5%) exhibiting the highest activity. This was followed by reverse phase - high performance liquid chromatography (RP-HPLC) with an octadecyl silica column (Inertsil ODS-3) using methanol:water 15:85 at a flow rate of 1.0 mL/min. Among the 13 fractions separated with the RP-HPLC, fraction 3.5 exhibited the highest ACE inhibitory activity (84.1%). The peptide sequence ACPGPNPGRP (IC50 2.03 μM) from fraction 3.5 was identified using Matrix-assisted laser desorption/ionization with time-of-flight tandem mass spectroscopy analysis (MALDI-TOF/MS).

  17. Necessity of angiotensin-converting enzyme-related gene for cardiac functions and longevity of Drosophila melanogaster assessed by optical coherence tomography

    NASA Astrophysics Data System (ADS)

    Liao, Fang-Tsu; Chang, Cheng-Yi; Su, Ming-Tsan; Kuo, Wen-Chuan

    2014-01-01

    Prior studies have established the necessity of an angiotensin-converting enzyme-related (ACER) gene for heart morphogenesis of Drosophila. Nevertheless, the physiology of ACER has yet to be comprehensively understood. Herein, we employed RNA interference to down-regulate the expression of ACER in Drosophila's heart and swept source optical coherence tomography to assess whether ACER is required for cardiac functions in living adult flies. Several contractile parameters of Drosophila heart, including the heart rate (HR), end-diastolic diameter (EDD), end-systolic diameter (ESD), percent fractional shortening (%FS), and stress-induced cardiac performance, are shown, which are age dependent. These age-dependent cardiac functions declined significantly when ACER was down-regulated. Moreover, the lifespans of ACER knock-down flies were significantly shorter than those of wild-type control flies. Thus, we posit that ACER, the Drosophila ortholog of mammalian angiotensin-converting enzyme 2 (ACE2), is essential for both heart physiology and longevity of animals. Since mammalian ACE2 controls many cardiovascular physiological features and is implicated in cardiomyopathies, our findings that ACER plays conserved roles in genetically tractable animals will pave the way for uncovering the genetic pathway that controls the renin-angiotensin system.

  18. The FAD-Dependent Tricarballylate Dehydrogenase (TcuA) Enzyme of Salmonella enterica Converts Tricarballylate into cis-Aconitate†

    PubMed Central

    Lewis, Jeffrey A.; Escalante-Semerena, Jorge C.

    2006-01-01

    Tricarballylate is the causative agent of grass tetany, a ruminant disease characterized by acute magnesium deficiency. Tricarballylate toxicity has been attributed to its ability to chelate magnesium and to inhibit aconitase, a Krebs cycle enzyme. Neither the ruminant nor the normal rumen flora can catabolize tricarballylate to ameliorate its toxic effects. However, the gram-negative enterobacterium Salmonella enterica can use tricarballylate as a carbon and energy source, providing an opportunity to study the genes and enzymes required for tricarballylate catabolism. The tricarballylate utilization (tcu) genes are organized into two transcriptional units, i.e., tcuR and tcuABC. Here, we report the initial biochemical analysis of TcuA. TcuA catalyzed the oxidation of tricarballylate to cis-aconitate. The apparent Km of TcuA for tricarballylate was 3.8 ± 0.4 mM, with a Vmax of 7.9 ± 0.3 mM min−1, turnover number (kcat) of 6.7 × 10−2 s−1, and a catalytic efficiency (kcat/Km) of 17.8 M−1 s−1. Optimal activity was measured at pH 7.5 and 30°C. The enzyme was inactivated at 45°C. One mole of FAD was present per mole of TcuA. We propose a role for TcuB as an electron shuttle protein responsible for oxidizing FADH2 back to FAD in TcuA. PMID:16855237

  19. In silico and in vitro analyses of the angiotensin-I converting enzyme inhibitory activity of hydrolysates generated from crude barley (Hordeum vulgare) protein concentrates.

    PubMed

    Gangopadhyay, Nirupama; Wynne, Kieran; O'Connor, Paula; Gallagher, Eimear; Brunton, Nigel P; Rai, Dilip K; Hayes, Maria

    2016-07-15

    Angiotensin-I-converting enzyme (ACE-I) plays a key role in control of hypertension, and type-2 diabetes mellitus, which frequently co-exist. Our current work utilised in silico methodologies and peptide databases as tools for predicting release of ACE-I inhibitory peptides from barley proteins. Papain was the enzyme of choice, based on in silico analysis, for experimental hydrolysis of barley protein concentrate, which was performed at the enzyme's optimum conditions (60 °C, pH 6.0) for 24 h. The generated hydrolysate was subjected to molecular weight cut-off (MWCO) filtration, following which the non-ultrafiltered hydrolysate (NUFH), and the generated 3 kDa and 10 kDa MWCO filtrates were assessed for their in vitro ACE-I inhibitory activities. The 3 kDa filtrate (1 mg/ml), that demonstrated highest ACE-I inhibitory activity of 70.37%, was characterised in terms of its peptidic composition using mass spectrometry and 1882 peptides derived from 61 barley proteins were identified, amongst which 15 peptides were selected for chemical synthesis based on their predicted ACE-I inhibitory properties. Of the synthesized peptides, FQLPKF and GFPTLKIF were most potent, demonstrating ACE-I IC50 values of 28.2 μM and 41.2 μM respectively.

  20. Redirection of pyruvate flux toward desired metabolic pathways through substrate channeling between pyruvate kinase and pyruvate-converting enzymes in Saccharomyces cerevisiae.

    PubMed

    Kim, Sujin; Bae, Sang-Jeong; Hahn, Ji-Sook

    2016-04-07

    Spatial organization of metabolic enzymes allows substrate channeling, which accelerates processing of intermediates. Here, we investigated the effect of substrate channeling on the flux partitioning at a metabolic branch point, focusing on pyruvate metabolism in Saccharomyces cerevisiae. As a platform strain for the channeling of pyruvate flux, PYK1-Coh-Myc strain was constructed in which PYK1 gene encoding pyruvate kinase is tagged with cohesin domain. By using high-affinity cohesin-dockerin interaction, the pyruvate-forming enzyme Pyk1 was tethered to heterologous pyruvate-converting enzymes, lactate dehydrogenase and α-acetolactate synthase, to produce lactic acid and 2,3-butanediol, respectively. Pyruvate flux was successfully redirected toward desired pathways, with a concomitant decrease in ethanol production even without genetic attenuation of the ethanol-producing pathway. This pyruvate channeling strategy led to an improvement of 2,3-butanediol production by 38%, while showing a limitation in improving lactic acid production due to a reduced activity of lactate dehydrogenase by dockerin tagging.

  1. Angiotensin-I Converting Enzyme (ACE) Inhibitory and Anti-Hypertensive Effect of Protein Hydrolysate from Actinopyga lecanora (Sea Cucumber) in Rats

    PubMed Central

    Sadegh Vishkaei, Mahdokht; Ebrahimpour, Afshin; Abdul-Hamid, Azizah; Ismail, Amin; Saari, Nazamid

    2016-01-01

    Food protein hydrolysates are known to exhibit angiotensin converting enzyme (ACE) inhibitory properties and can be used as a novel functional food for prevention of hypertension. This study evaluated the ACE inhibitory potentials of Actinopyga lecanora proteolysate (ALP) in vivo. The pre-fed rats with ALP at various doses (200, 400, 800 mg/kg body weight) exhibited a significant (p ≤ 0.05) suppression effect after inducing hypertension. To determine the optimum effective dose that will produce maximal reduction in blood pressure, ALP at three doses was fed to the rats after inducing hypertension. The results showed that the 800 mg/kg body weight dose significantly reduced blood pressure without noticeable negative physiological effect. In addition, there were no observable changes in the rats’ heart rate after oral administration of the ALP. It was concluded that Actinopyga lecanora proteolysate could potentially be used for the development of functional foods and nutraceuticals for prevention and treatment of hypertension. PMID:27706040

  2. Angiotensin-I Converting Enzyme (ACE) Inhibitory and Anti-Hypertensive Effect of Protein Hydrolysate from Actinopyga lecanora (Sea Cucumber) in Rats.

    PubMed

    Sadegh Vishkaei, Mahdokht; Ebrahimpour, Afshin; Abdul-Hamid, Azizah; Ismail, Amin; Saari, Nazamid

    2016-09-30

    Food protein hydrolysates are known to exhibit angiotensin converting enzyme (ACE) inhibitory properties and can be used as a novel functional food for prevention of hypertension. This study evaluated the ACE inhibitory potentials of Actinopyga lecanora proteolysate (ALP) in vivo. The pre-fed rats with ALP at various doses (200, 400, 800 mg/kg body weight) exhibited a significant (p ≤ 0.05) suppression effect after inducing hypertension. To determine the optimum effective dose that will produce maximal reduction in blood pressure, ALP at three doses was fed to the rats after inducing hypertension. The results showed that the 800 mg/kg body weight dose significantly reduced blood pressure without noticeable negative physiological effect. In addition, there were no observable changes in the rats' heart rate after oral administration of the ALP. It was concluded that Actinopyga lecanora proteolysate could potentially be used for the development of functional foods and nutraceuticals for prevention and treatment of hypertension.

  3. Apricot and other seed stones: amygdalin content and the potential to obtain antioxidant, angiotensin I converting enzyme inhibitor and hypocholesterolemic peptides.

    PubMed

    García, M C; González-García, E; Vásquez-Villanueva, R; Marina, M L

    2016-11-09

    Stones from olives and Prunus genus fruits are cheap and sustainable sources of proteins and could be potential sources of bioactive peptides. The main limitation to the use of these seeds is the presence of amygdalin. This work proposes to determine amygdalin in olive and Prunus seeds and in protein isolates obtained from them. Moreover, antioxidant, angiotensin I converting enzyme (ACE) inhibitor, and hypocholesterolemic properties will be evaluated in hydrolysates obtained from these seeds. Despite some seeds contained amygdalin, all protein isolates were free of this substance. Two different procedures to obtain bioactive peptides from protein isolates were examined: gastrointestinal digestion and processing with Alcalase, Flavourzyme or Thermolysin. Higher antioxidant, ACE inhibitor and hypocholesterolemic activities were observed when proteins were processed with Alcalase, Flavourzyme or Thermolysin. The highest antioxidant and ACE inhibitor capacities were observed for the Prunus genus seed hydrolysates while the highest capacity to reduce micellar cholesterol solubility was observed for the apricot and olive seed hydrolysates.

  4. Scleroderma renal crisis during intravenous cyclophosphamide pulse therapy for complicated interstitial lung disease was successfully treated with angiotensin converting enzyme inhibitor and plasma exchange

    PubMed Central

    Nagamura, Norihiro; Kin, Seikon

    2016-01-01

    ABSTRACT Systemic sclerosis (SSc) is a multiorgan disorder involving the skin, heart, lungs, kidneys, and intestines. Progressive interstitial lung disease (ILD) is a serious complication in SSc patients, and cyclophosphamide (CYC) is the only recommended therapy for this condition;1) however, its clinical effectiveness is not sufficient. Scleroderma renal crisis (SRC) is a rare complication, characterized by acute renal failure and progressive hypertension. Angiotensin-converting-enzyme inhibitor (ACE-i) is a widely accepted therapy for SRC. We report an SSc patient with SRC and progressive ILD who underwent treatment with CYC and successful treatment with ACE-i and plasma exchange (PE). SRC and ILD are significant contributors to morbidity and mortality among SSc patients, and the therapy for these disorders is of great interest to rheumatologists. This study presents the possibility of favorable effects of PE for SSc-associated ILD and SRC. PMID:27578917

  5. Purification and characterisation of a novel angiotensin-I converting enzyme (ACE)-inhibitory peptide derived from the enzymatic hydrolysate of Enteromorpha clathrata protein.

    PubMed

    Pan, Saikun; Wang, Shujun; Jing, Lingling; Yao, Dongrui

    2016-11-15

    Hydrolysates containing angiotensin-I converting enzyme (ACE)-inhibitory peptide were prepared from Enteromorpha clathrata protein using alcalase. The hydrolysates were fractionated into two molecular-weight ranges (below and above 10kDa) by ultrafiltration. The below-10kDa fraction showed higher ACE-inhibitory activity and was subsequently purified by Sephadex G-15 gel filtration chromatography. The structure of active peptide was identified as Pro-Ala-Phe-Gly by HPLC-Q-TOF-MS and its IC50 value was 35.9μM. The yield of this peptide from E. clathrata protein was 0.82%. Lineweaver-Burk plots demonstrated that the inhibitory kinetic mechanism of this peptide was non-competitive. Stability study revealed that the purified peptide showed resistance against gastrointestinal proteases. Thus, E. clathrata protein hydrolysate treated with alcalase is a beneficial ingredient of nutraceuticals and pharmaceuticals against hypertension and related diseases.

  6. Screening and profiling stilbene-type natural products with angiotensin-converting enzyme inhibitory activity from Ampelopsis brevipedunculata var. hancei (Planch.) Rehder.

    PubMed

    Su, Pei-Shiuan; Doerksen, Robert J; Chen, Sin-Hong; Sung, Wang-Chou; Juan, Chia-Chi; Rawendra, Reynetha D S; Chen, Chiy-Rong; Li, Jia-Wei; Aisha; Huang, Tzou-Chi; Liao, Ming-Huei; Chang, Chi-I; Hsu, Jue-Liang

    2015-04-10

    In this study, we screened 10 resveratrol derivatives isolated from Ampelopsis brevipedunculata var. hancei (Planch.) Rehder (ABH) for angiotensin I converting enzyme (ACE) inhibitory (ACEI) activity. Among these compounds, (+)-hopeaphenol and (+)-vitisin A showed the lowest IC50 values (∼ 1.5 μM) toward ACE. In addition, the compounds' abundances and distributions in ABH were profiled using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Interestingly, trimers and tetramers of resveratrol were mainly obtained from the bark of ABH when 90% ethanol was used for extraction. This result implies that the antihypertension effect of ABH extract may be mainly contributed by (+)-hopeaphenol (F1) and (+)-vitisin A (F2) in the ABH bark due to their remarkable ACE inhibitions. Moreover, the sizes and structures of these compounds were further correlated to their affinities toward ACE using molecular docking calculations. The results showed that resveratrol tetramers interact with ACE more favorably than other smaller oligomers.

  7. Effects of prolonged angiotensin-converting enzyme inhibitor treatment on amyloid beta-protein metabolism in mouse models of Alzheimer disease.

    PubMed

    Hemming, Matthew L; Selkoe, Dennis J; Farris, Wesley

    2007-04-01

    Genetic and pathologic studies have associated angiotensin-converting enzyme (ACE) with Alzheimer disease. Previously, we and others have reported that ACE degrades in vitro the amyloid beta-protein (Abeta), a putative upstream initiator of Alzheimer disease. These studies support the hypothesis that deficiency in ACE-mediated Abeta proteolysis could increase Alzheimer disease risk and raise the question of whether ACE inhibitors, a commonly prescribed class of anti-hypertensive medications, can elevate Abeta levels in vivo. To test this hypothesis, we administered the ACE inhibitor captopril to two lines of APP transgenic mice harboring either low levels of Abeta or high levels of Abeta with associated plaque deposition. In both models, we show that captopril does not affect cerebral Abeta levels in either soluble or insoluble pools. Furthermore, we find no change in plaque deposition or in peripheral Abeta levels. Data from these Alzheimer models suggest that captopril and similar ACE inhibitors do not cause Abeta accumulation in vivo.

  8. How should we manage heart failure developing in patients already treated with angiotensin-converting enzyme inhibitors and beta-blockers for hypertension, diabetes or coronary disease?

    PubMed

    Gustafsson, Finn; Segura, Julian; Ruilope, Luis M

    2010-08-01

    An increasing number of patients in the community are being treated with angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs) and beta-blockers for hypertension, coronary disease or diabetic renal and vascular complications. Some of these patients will develop heart failure despite such treatment. Based on data from hypertension trials it can be estimated that approximately 5% of treated patients will develop heart failure over 5 years. It is unclear whether patients developing heart failure on and off ACE-inhibitors or beta-blockers, respectively, at the time of heart failure diagnosis have similar prognosis.Treatment options for patients developing heart failure while already treated with ACE inhibitors/ARBs and beta-blockers are very limited if current heart failure guidelines are followed. In this review possible strategies are outlined and important areas for research are identified. It is suggested that trials are designed specifically to address prognosis and treatment in this growing population.

  9. Differences in the clinical effects of angiotensin-converting enzyme inhibitors and Angiotensin receptor blockers: a critical review of the evidence.

    PubMed

    Dézsi, Csaba András

    2014-06-01

    The renin-angiotensin-aldosterone system plays a major role in the pathophysiology of hypertension and closely related cardio- and cerebrovascular events. Although both angiotensin-converting enzyme (ACE) inhibitors and angiotensin receptor antagonists (angiotensin receptor blockers; ARBs) are equally important in the treatment of hypertension, according to the results of recent years, there might be substantial differences in their cardiovascular protective effects, and these differences might be explained by our increasing knowledge of their non-overlapping mechanisms of action. The number of studies investigating how ACE inhibitors and ARB agents differ will certainly be increasing in the future. ACE inhibitors are the safe therapeutic opportunity for hypertensive patients at high risk, with a cardiological comorbidity.

  10. Influence of angiotensin converting enzyme (ACE) gene rs4362 polymorphism on the progression of kidney failure in patients with autosomal dominant polycystic kidney disease (ADPKD)

    PubMed Central

    Ramanathan, Gnanasambandan; Ghosh, Santu; Elumalai, Ramprasad; Periyasamy, Soundararajan; Lakkakula, Bhaskar V.K.S.

    2016-01-01

    Background & objectives: Autosomal dominant polycystic kidney disease (ADPKD) is an inherited systemic disorder, characterized by the fluid filled cysts in the kidneys leading to end stage renal failure in later years of life. Hypertension is one of the major factors independently contributing to the chronic kidney disease (CKD) progression. The renin-angiotensin aldosterone system (RAAS) genes have been extensively studied as hypertension candidate genes. The aim of the present study was to investigate the role of angiotensin converting enzyme tagging - single nucleotide polymorphisms (ACE tag-SNPs) in progression of CKD in patients with ADPKD. Methods: In the present study six ACE tagSNPs (angiotensin converting enzyme tag single nucleotide polymorphisms) and insertion/deletion (I/D) in 102 ADPKD patients and 106 control subjects were investigated. The tagSNPs were genotyped using FRET-based KASPar method and ACE ID by polymerase chain reaction (PCR) and electrophoresis. Genotypes and haplotypes were compared between ADPKD patients and controls. Univariate and multivariate logistic regression analyses were performed to assess the effect of genotypes and hypertension on CKD advancement. Mantel-Haenszel (M-H) stratified analysis was performed to study the relationship between different CKD stages and hypertension and their interaction. Results: All loci were polymorphic and except rs4293 SNP the remaining loci followed Hardy-Weinberg equilibrium. Distribution of ACE genotypes and haplotypes in controls and ADPKD patients was not significant. A significant linkage disequilibrium (LD) was observed between SNPs forming two LD blocks. The univariate analysis revealed that the age, hypertension, family history of diabetes and ACE rs4362 contributed to the advancement of CKD. Interpretation & conclusions: The results suggest that the ACE genotypes are effect modifiers of the relationship between hypertension and CKD advancement among the ADPKD patients. PMID:27748299

  11. Natural soluble interleukin-15Ralpha is generated by cleavage that involves the tumor necrosis factor-alpha-converting enzyme (TACE/ADAM17).

    PubMed

    Budagian, Vadim; Bulanova, Elena; Orinska, Zane; Ludwig, Andreas; Rose-John, Stefan; Saftig, Paul; Borden, Ernest C; Bulfone-Paus, Silvia

    2004-09-24

    This study shows that the high affinity alpha-chain of the interleukin (IL)-15 receptor exists not only in membrane-anchored but also in soluble form. Soluble IL-15Ralpha (sIL-15Ralpha) can be detected in mouse sera and cell-conditioned media by enzyme-linked immunosorbent assay and by immunoprecipitation and Western blotting. This protein has a molecular mass of about 30 kDa because of the presence of a single N-glycosylation site, which is reduced to 26 kDa after N-glycosidase treatment. Transmembrane IL-15Ralpha is constitutively converted into its soluble form by proteolytic cleavage that involves tumor necrosis factor-alpha-converting enzyme (TACE), and this process is further enhanced by phorbol 12-myristate 13-acetate (PMA) stimulation. The hydroxamate GW280264X, which is capable of blocking TACE and the closely related disintegrin-like metalloproteinase 10 (ADAM10), effectively inhibited both spontaneous and PMA-inducible cleavage of IL-15Ralpha, whereas GI254023X, which preferentially blocks ADAM10, was ineffective. Overexpression of TACE but not ADAM10 in COS-7 cells enhanced the constitutive and PMA-inducible cleavage of IL-15Ralpha. Moreover, murine fibroblasts deficient in TACE but not ADAM10 expression exhibited a significant reduction in the spontaneous and inducible IL-15Ralpha shedding, whereas a reconstitution of TACE in these cells restored the release of sIL-15Ralpha, thereby suggesting that TACE-mediated proteolysis may represent a major mechanism for sIL-15Ralpha generation in mice. The existence of natural sIL-15Ralpha offers novel insights into the complex biology of IL-15 and envisages a new level for therapeutic intervention.

  12. Angiotensin-(1-7) prevents systemic hypertension, attenuates oxidative stress and tubulointerstitial fibrosis, and normalizes renal angiotensin-converting enzyme 2 and Mas receptor expression in diabetic mice.

    PubMed

    Shi, Yixuan; Lo, Chao-Sheng; Padda, Ranjit; Abdo, Shaaban; Chenier, Isabelle; Filep, Janos G; Ingelfinger, Julie R; Zhang, Shao-Ling; Chan, John S D

    2015-05-01

    We investigated the relationship between Ang-(1-7) [angiotensin-(1-7)] action, sHTN (systolic hypertension), oxidative stress, kidney injury, ACE2 (angiotensin-converting enzyme-2) and MasR [Ang-(1-7) receptor] expression in Type 1 diabetic Akita mice. Ang-(1-7) was administered daily [500 μg/kg of BW (body weight) per day, subcutaneously] to male Akita mice from 14 weeks of age with or without co-administration of an antagonist of the MasR, A779 (10 mg/kg of BW per day). The animals were killed at 20 weeks of age. Age-matched WT (wild-type) mice served as controls. Ang-(1-7) administration prevented sHTN and attenuated kidney injury (reduced urinary albumin/creatinine ratio, glomerular hyperfiltration, renal hypertrophy and fibrosis, and tubular apoptosis) without affecting blood glucose levels in Akita mice. Ang-(1-7) also attenuated renal oxidative stress and the expression of oxidative stress-inducible proteins (NADPH oxidase 4, nuclear factor erythroid 2-related factor 2, haem oxygenase 1), pro-hypertensive proteins (angiotensinogen, angiotensin-converting enzyme, sodium/hydrogen exchanger 3) and profibrotic proteins (transforming growth factor-β1 and collagen IV), and increased the expression of anti-hypertensive proteins (ACE2 and MasR) in Akita mouse kidneys. These effects were reversed by A779. Our data suggest that Ang-(1-7) plays a protective role in sHTN and RPTC (renal proximal tubular cell) injury in diabetes, at least in part, through decreasing renal oxidative stress-mediated signalling and normalizing ACE2 and MasR expression.

  13. Angiotensin Converting Enzyme 2/Ang-(1–7)/Mas Axis Protects Brain from Ischemic Injury with a Tendency of Age-dependence

    PubMed Central

    Zheng, Jiao-Lin; Li, Guang-Ze; Chen, Shu-Zhen; Wang, Jin-Ju; Olson, James E.; Xia, Hui-Jing; Lazartigues, Eric; Zhu, Yu-Lan; Chen, Yan-Fang

    2016-01-01

    SUMMARY Background The angiotensin (Ang) converting enzyme 2 (ACE2)/Ang-(1-7)/Mas receptor pathway is an important component of the renin–angiotensin system and has been suggested to exert beneficial effects in ischemic stroke. Aims This study explored whether the ACE2/Ang-(1-7)/Mas pathway has a protective effect on cerebral ischemic injury and whether this effect is affected by age. Methods We used three-month and eight-month transgenic mice with neural over-expression of ACE2 (SA) and their age-matched non-transgenic (NT) controls. Neurological deficits and ischemic stroke volume were determined following middle cerebral artery occlusion (MCAO). In oxygen and glucose deprivation (OGD) experiments on brain slices, the effects of the Mas receptor agonist (Ang1-7) or antagonist (A779) on tissue swelling, Nox2/Nox4 expression reactive oxygen species (ROS) production and cell death were measured. Results (1) Middle cerebral artery occlusion -induced ischemic injury and neurological deficit were reduced in SA mice, especially in eight-month animals; (2) OGD-induced tissue swelling and cell death were decreased in SA mice with a greater reduction seen in eight-month mice; (3) Ang-(1–7) and A779 had opposite effects on OGD-induced responses, which correlated with changes in Nox2/Nox4 expression and ROS production. Conclusions Angiotensin converting enzyme 2/Ang-(1-7)/Mas axis protects brain from ischemic injury via the Nox/ROS signaling pathway, with a greater effect in older animals. PMID:24581232

  14. The Angiotensin-converting enzyme inhibitor captopril inhibits poly(adp-ribose) polymerase activation and exerts beneficial effects in an ovine model of burn and smoke injury.

    PubMed

    Asmussen, Sven; Bartha, Eva; Olah, Gabor; Sbrana, Elena; Rehberg, Sebastian W; Yamamoto, Yusuke; Enkhbaatar, Perenlei; Hawkins, Hal K; Ito, Hiroshi; Cox, Robert A; Traber, Lillian D; Traber, Daniel L; Szabo, Csaba

    2011-10-01

    We investigated the effect of the angiotensin-converting enzyme (ACE) inhibitor captopril in a clinically relevant ovine model of smoke and burn injury, with special reference to oxidative stress and activation of poly(ADP-ribose) polymerase, in the lung and in circulating leukocytes. Female, adult sheep (28-40 kg) were divided into three groups. After tracheostomy and under deep anesthesia, both vehicle-control-treated (n = 5) and captopril-treated (20 mg/kg per day, i.v., starting 0.5 h before the injury) (n = 5) groups were subjected to 2 × 20%, third-degree burn injury and were insufflated with 48 breaths of cotton smoke. A sham group not receiving burn/smoke was also studied (n = 5). Animals were mechanically ventilated and fluid resuscitated for 24 h in the awake state. Burn and smoke injury resulted in an upregulation of ACE in the lung, evidenced by immunohistochemical determination and Western blotting. Burn and smoke injury resulted in pulmonary dysfunction, as well as systemic hemodynamic alterations. Captopril treatment of burn and smoke animals improved PaO2/FiO2 ratio and pulmonary shunt fraction and reduced the degree of lung edema. There was a marked increase in PAR levels in circulating leukocytes after burn/smoke injury, which was significantly decreased by captopril. The pulmonary level of ACE and the elevated pulmonary levels of transforming growth factor β in response to burn and smoke injury were significantly decreased by captopril treatment. Our results suggest that the ACE inhibitor captopril exerts beneficial effects on the pulmonary function in burn/smoke injury. The effects of the ACE inhibitor may be related to the prevention of reactive oxygen species-induced poly(ADP-ribose)polymerase overactivation. Angiotensin-converting enzyme inhibition may also exert additional beneficial effects by inhibiting the expression of the profibrotic mediator transforming growth factor β.

  15. iPS-derived MSCs from an expandable bank to deliver a prodrug-converting enzyme that limits growth and metastases of human breast cancers

    PubMed Central

    Ullah, M; Kuroda, Y; Bartosh, T J; Liu, F; Zhao, Q; Gregory, C; Reger, R; Xu, J; Lee, R H; Prockop, D J

    2017-01-01

    One attractive strategy to treat cancers is to deliver an exogenous enzyme that will convert a non-toxic compound to a highly toxic derivative. The strategy was tested with viral vectors but was disappointing because the efficiency of transduction into tumor cells was too low. Recent reports demonstrated that the limitation can be addressed by using tissue-derived mesenchymal stromal cells (MSCs) to deliver enzyme/prodrug systems that kill adjacent cancer cells through bystander effects. Here we addressed the limitation that tissue-derived MSCs vary in their properties and are difficult to generate in the large numbers needed for clinical applications. We prepared a Feeder Stock of MSCs from induced pluripotent stem cells (iPSs) that provided an extensively expandable source of standardized cells. We then transduced the iPS-derived MSCs to express cytosine deaminase and injected them locally into a mouse xenogeneic model of human breast cancer. After administration of the prodrug (5-fluorocytosine), the transduced iPS-MSCs both limited growth of preformed tumors and decreased lung metastases. PMID:28179988

  16. iPS-derived MSCs from an expandable bank to deliver a prodrug-converting enzyme that limits growth and metastases of human breast cancers.

    PubMed

    Ullah, M; Kuroda, Y; Bartosh, T J; Liu, F; Zhao, Q; Gregory, C; Reger, R; Xu, J; Lee, R H; Prockop, D J

    2017-01-01

    One attractive strategy to treat cancers is to deliver an exogenous enzyme that will convert a non-toxic compound to a highly toxic derivative. The strategy was tested with viral vectors but was disappointing because the efficiency of transduction into tumor cells was too low. Recent reports demonstrated that the limitation can be addressed by using tissue-derived mesenchymal stromal cells (MSCs) to deliver enzyme/prodrug systems that kill adjacent cancer cells through bystander effects. Here we addressed the limitation that tissue-derived MSCs vary in their properties and are difficult to generate in the large numbers needed for clinical applications. We prepared a Feeder Stock of MSCs from induced pluripotent stem cells (iPSs) that provided an extensively expandable source of standardized cells. We then transduced the iPS-derived MSCs to express cytosine deaminase and injected them locally into a mouse xenogeneic model of human breast cancer. After administration of the prodrug (5-fluorocytosine), the transduced iPS-MSCs both limited growth of preformed tumors and decreased lung metastases.

  17. Human gut endogenous proteins as a potential source of angiotensin-I-converting enzyme (ACE-I)-, renin inhibitory and antioxidant peptides.

    PubMed

    Dave, Lakshmi A; Hayes, Maria; Montoya, Carlos A; Rutherfurd, Shane M; Moughan, Paul J

    2016-02-01

    It is well known that endogenous bioactive proteins and peptides play a substantial role in the body's first line of immunological defence, immune-regulation and normal body functioning. Further, the peptides derived from the luminal digestion of proteins are also important for body function. For example, within the peptide database BIOPEP (http://www.uwm.edu.pl/biochemia/index.php/en/biopep) 12 endogenous antimicrobial and 64 angiotensin-I-converting enzyme (ACE-I) inhibitory peptides derived from human milk and plasma proteins are listed. The antimicrobial peptide database (http://aps.unmc.edu/AP/main.php) lists over 111 human host-defence peptides. Several endogenous proteins are secreted in the gut and are subject to the same gastrointestinal digestion processes as food proteins derived from the diet. The human gut endogenous proteins (GEP) include mucins, serum albumin, digestive enzymes, hormones, and proteins from sloughed off epithelial cells and gut microbiota, and numerous other secreted proteins. To date, much work has been carried out regarding the health altering effects of food-derived bioactive peptides but little attention has been paid to the possibility that GEP may also be a source of bioactive peptides. In this review, we discuss the potential of GEP to constitute a gut cryptome from which bioactive peptides such as ACE-I inhibitory, renin inhibitory and antioxidant peptides may be derived.

  18. Optimization of Bromelain-Aided Production of Angiotensin I-Converting Enzyme Inhibitory Hydrolysates from Stone Fish Using Response Surface Methodology.

    PubMed

    Muhammad Auwal, Shehu; Zarei, Mohammad; Abdul-Hamid, Azizah; Saari, Nazamid

    2017-03-31

    The stone fish is an under-utilized sea cucumber with many nutritional and ethno-medicinal values. This study aimed to establish the conditions for its optimum hydrolysis with bromelain to generate angiotensin I-converting enzyme (ACE)-inhibitory hydrolysates. Response surface methodology (RSM) based on a central composite design was used to model and optimize the degree of hydrolysis (DH) and ACE-inhibitory activity. Process conditions including pH (4-7), temperature (40-70 °C), enzyme/substrate (E/S) ratio (0.5%-2%) and time (30-360 min) were used. A pH of 7.0, temperature of 40 °C, E/S ratio of 2% and time of 240 min were determined using a response surface model as the optimum levels to obtain the maximum ACE-inhibitory activity of 84.26% at 44.59% degree of hydrolysis. Hence, RSM can serve as an effective approach in the design of experiments to improve the antihypertensive effect of stone fish hydrolysates, which can thus be used as a value-added ingredient for various applications in the functional foods industries.

  19. Studies on the effect of normal labour and obstetric analgesia on maternal and cord venous plasma angiotensin converting enzyme activity in primigravidae.

    PubMed

    Odum, C U; Broughton Pipkin, F

    1990-01-01

    A spectrophotometric (optimized) assay of plasma angiotensin converting enzyme (ACE) activity was carried out in the plasma of primigravid subjects before and after labour; and in the plasma of cord various blood samples obtained from these subjects. The assay was based on the calorimetric determination of hippurate with cyanuric chloride/dioxan reagent, as described by Hurst and Lovell-Smith. The coefficient of variation (CV) for this method during the assay ranged from 7.36% to 8.19% and from 9.20% to 9.79% for the hippurate standards and the control plasma samples respectively. The mean +/- SD of maternal plasma ACE activity before labour and at delivery in the primigravid subjects were 22.23 +/- 4.17 and 16.44 +/- 1.71 units-1 min-1 respectively; while the corresponding value of enzyme activity in the cord venous plasma for these subjects was 15.71 +/- 1.61 unit-1 min-1. Normal labour did not appear to alter significantly the level of maternal and cord venous plasma ACE activity. It would appear that epidural analgesia has a significant effect on the level of maternal plasma ACE activity during labour (x2 = 12.59 P less than 0.05), but not on the cord venous plasma ACE activity.

  20. Degenerate sequence recognition by the monomeric restriction enzyme: single mutation converts BcnI into a strand-specific nicking endonuclease

    PubMed Central

    Kostiuk, Georgij; Sasnauskas, Giedrius; Tamulaitiene, Giedre; Siksnys, Virginijus

    2011-01-01

    Unlike orthodox Type II restriction endonucleases that are homodimers and interact with the palindromic 4–8-bp DNA sequences, BcnI is a monomer which has a single active site but cuts both DNA strands within the 5′-CC↓CGG-3′/3′-GGG↓CC-5′ target site (‘↓’ designates the cleavage position). Therefore, after cutting the first strand, the BcnI monomer must re-bind to the target site in the opposite orientation; but in this case, it runs into a different central base because of the broken symmetry of the recognition site. Crystal-structure analysis shows that to accept both the C:G and G:C base pairs at the center of its target site, BcnI employs two symmetrically positioned histidines H77 and H219 that presumably change their protonation state depending on the binding mode. We show here that a single mutation of BcnI H77 or H219 residues restricts the cleavage activity of the enzyme to either the 5′-CCCGG-3′ or the 5′-CCGGG-3′ strand, thereby converting BcnI into a strand-specific nicking endonuclease. This is a novel approach for engineering of monomeric restriction enzymes into strand-specific nucleases. PMID:21227928

  1. Endothelin-converting enzymes degrade intracellular β-amyloid produced within the endosomal/lysosomal pathway and autophagosomes.

    PubMed

    Pacheco-Quinto, Javier; Eckman, Elizabeth A

    2013-02-22

    Impairments in Aβ removal are increasingly being considered as a possible cause for the abnormal Aβ build-up typical of Alzheimer disease. Of particular interest is a pool of Aβ that accumulates intraneuronally and may contribute to neuronal toxicity. The mechanism for intraneuronal accumulation, however, is not well understood and is commonly attributed to impaired removal of extracellular Aβ by neurons. Based on the intracellular distribution of the well established Aβ degrading enzymes, ECE-1 and ECE-2, we tested whether impairments in their catalytic activity could lead to intracellular Aβ accumulation. Using SH-SY5Y cells overexpressing wild-type amyloid precursor protein and pharmacological inhibition of endogenous ECE activity, we found that ECEs participate in the degradation of at least two distinct pools of Aβ; one destined for secretion and the other being produced and degraded within the endosomal-autophagic-lysosomal pathways. Although ECE-1 regulates both pools of Aβ, ECE-2 regulates mainly the intracellular pool of the peptide. Consistent with this result, ECE-2 was found to co-localize with markers of the endosomal/lysosomal pathway but not with a trans-Golgi network marker. Furthermore, ECE-2 was detected in autophagic vesicles in cells treated with chloroquine. Under these conditions, ECE inhibition produced significantly higher elevations in intracellular Aβ than chloroquine treatment alone. This study highlights the existence of Aβ clearance mechanisms by ECEs at intracellular sites of production. Alterations in ECE activity may be considered as a cause for increased intraneuronal Aβ in Alzheimer disease.

  2. Neuroprotective Effect of Scutellarin on Ischemic Cerebral Injury by Down-Regulating the Expression of Angiotensin-Converting Enzyme and AT1 Receptor

    PubMed Central

    Han, Jichun; Zhou, Mingjie; Ren, Huanhuan; Pan, Qunwen; Zheng, Chunli; Zheng, Qiusheng

    2016-01-01

    Background and Purpose Previous studies have demonstrated that angiotensin-converting enzyme (ACE) is involved in brain ischemic injury. In the present study, we investigated whether Scutellarin (Scu) exerts neuroprotective effects by down-regulating the Expression of Angiotensin-Converting Enzyme and AT1 receptor in a rat model of permanent focal cerebral ischemia. Methods Adult Sprague–Dawley rats were administrated with different dosages of Scu by oral gavage for 7 days and underwent permanent middle cerebral artery occlusion (pMCAO). Blood pressure was measured 7 days after Scu administration and 24 h after pMCAO surgery by using a noninvasive tail cuff method. Cerebral blood flow (CBF) was determined by Laser Doppler perfusion monitor and the neuronal dysfunction was evaluated by analysis of neurological deficits before being sacrificed at 24 h after pMCAO. Histopathological change, cell apoptosis and infarct area were respectively determined by hematoxylin–eosin staining, terminal deoxynucleotidyl transfer-mediated dUTP nick end labeling (TUNEL) analysis and 2,3,5-triphenyltetrazolium chloride staining. Tissue angiotensin II (Ang II) and ACE activity were detected by enzyme-linked immunosorbent assays. The expression levels of ACE, Ang II type 1 receptor (AT1R), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1β (IL-1β) were measured by Western blot and real-time PCR. ACE inhibitory activity of Scu in vitro was detected by the photometric determination. Results Scu treatment dose-dependently decreased neurological deficit score, infarct area, cell apoptosis and morphological changes induced by pMCAO, which were associated with reductions of ACE and AT1R expression and the levels of Ang II, TNF-α, IL-6, and IL-1β in ischemic brains. Scu has a potent ACE inhibiting activity. Conclusion Scu protects brain from acute ischemic injury probably through its inhibitory effect on the ACE/Ang II/AT1 axis, CBF preservation and

  3. In vitro digestion of purified β-casein variants A(1), A(2), B, and I: effects on antioxidant and angiotensin-converting enzyme inhibitory capacity.

    PubMed

    Petrat-Melin, B; Andersen, P; Rasmussen, J T; Poulsen, N A; Larsen, L B; Young, J F

    2015-01-01

    Genetic polymorphisms of bovine milk proteins affect the protein profile of the milk and, hence, certain technological properties, such as casein (CN) number and cheese yield. However, reports show that such polymorphisms may also affect the health-related properties of milk. Therefore, to gain insight into their digestion pattern and bioactive potential, β-CN was purified from bovine milk originating from cows homozygous for the variants A(1), A(2), B, and I by a combination of cold storage, ultracentrifugation, and acid precipitation. The purity of the isolated β-CN was determined by HPLC, variants were verified by mass spectrometry, and molar extinction coefficients at λ=280nm were determined. β-Casein from each of the variants was subjected to in vitro digestion using pepsin and pancreatic enzymes. Antioxidant and angiotensin-converting enzyme (ACE) inhibitory capacities of the hydrolysates were assessed at 3 stages of digestion and related to that of the undigested samples. Neither molar extinction coefficients nor overall digestibility varied significantly between these 4 variants; however, clear differences in digestion pattern were indicated by gel electrophoresis. In particular, after 60min of pepsin followed by 5min of pancreatic enzyme digestion, one ≈4kDa peptide with the N-terminal sequence (106)H-K-E-M-P-F-P-K- was absent from β-CN variant B. This is likely a result of the (122)Ser to (122)Arg substitution in variant B introducing a novel trypsin cleavage site, leading to the changed digestion pattern. All investigated β-CN variants exhibited a significant increase in antioxidant capacity upon digestion, as measured by the Trolox-equivalent antioxidant capacity assay. After 60min of pepsin + 120min of pancreatic enzyme digestion, the accumulated increase in antioxidant capacity was ≈1.7-fold for the 4 β-CN variants. The ACE inhibitory capacity was also significantly increased by digestion, with the B variant reaching the highest inhibitory

  4. Involvement of human plasma angiotensin I-converting enzyme in the degradation of the haemoregulatory peptide N-acetyl-seryl-aspartyl-lysyl-proline.

    PubMed Central

    Rieger, K J; Saez-Servent, N; Papet, M P; Wdzieczak-Bakala, J; Morgat, J L; Thierry, J; Voelter, W; Lenfant, M

    1993-01-01

    The degradation of N-Ac-Ser-Asp-Lys-Pro (AcSDKP), a negative regulator controlling the proliferation of the haematopoietic stem cell, by enzymes present in human plasma, has been investigated. Radiolabelled AcSD[4-3H]KP ([3H]AcSDKP, 1 mM) was completely metabolized in human plasma with a half-life of 80 min, leading exclusively to the formation of radiolabelled lysine. The cleavage of AcSDKP was insensitive to classical proteinase inhibitors including leupeptin, but sensitive to metalloprotease inhibitors. The degradation was completely blocked by specific inhibitors of angiotensin I-converting enzyme (ACE; kininase II; peptidyldipeptide hydrolase, EC 3.4.15.1), showing that the first step of the hydrolysis was indeed due to ACE. In dialysed plasma, the hydrolysis proceeded at only 17% of the maximal rate, whereas addition of 20 mM NaCl led to the recovery of the initial rate observed with normal plasma. Hydrolysis of AcSDKP by commercial rabbit lung ACE generated the C-terminal dipeptide Lys-Pro. Thus, ACE cleaves AcSDKP by a dipeptidyl carboxypeptidase activity. In fact the formation of Lys-Pro was observed when AcSDKP was incubated in human plasma in the presence of HgCl2. These results suggest that ACE is involved in the first limiting step of AcSDKP degradation in human plasma. The second step seems to be under the control of a leupeptin- and E-64-insensitive, HgCl2-sensitive plasmatic enzyme. PMID:8257427

  5. Identification of novel dipeptidyl peptidase-IV and angiotensin-I-converting enzyme inhibitory peptides from meat proteins using in silico analysis.

    PubMed

    Lafarga, Tomas; O'Connor, Paula; Hayes, Maria

    2014-09-01

    Angiotensin-I-converting enzyme (ACE-I, EC 3.4.15.1), renin (EC 3.4.23.15), and dipeptidyl peptidase-IV (DPP-IV, EC 3.4.14.5) play key roles in the control of hypertension and the development of type-2 diabetes and other diseases associated with metabolic syndrome. The aim of this work was to utilize known in silico methodologies, peptide databases and software including ProtParam (http://web.expasy.org/protparam/), Basic Local Alignment Tool (BLAST), ExPASy PeptideCutter (http://web.expasy.org/peptide_cutter/) and BIOPEP (http://www.uwm.edu.pl/biochemia/index.php/pl/biopep) to assess the release of potentially bioactive DPP-IV, renin and ACE-I inhibitory peptides from bovine and porcine meat proteins including hemoglobin, collagen and serum albumin. These proteins were chosen as they are found commonly in meat by-products such as bone, blood and low-value meat cuts. In addition, the bioactivities of identified peptides were confirmed using chemical synthesis and in vitro bioassays. The concentration of peptide required to inhibit the activity of ACE-I and DPP-IV by 50% was determined for selected, active peptides. Novel ACE-I and DPP-IV inhibitory peptides were identified in this study using both in silico analysis and a literature search to streamline enzyme selection for peptide production. These novel peptides included the ACE-I inhibitory tri-peptide Ile-Ile-Tyr and the DPP-IV inhibitory tri-peptide Pro-Pro-Leu corresponding to sequences f (182-184) and f (326-328) of both porcine and bovine serum albumin which can be released following hydrolysis with the enzymes papain and pepsin, respectively. This work demonstrates that meat proteins are a suitable resource for the generation of bioactive peptides and further demonstrates the usefulness of in silico methodologies to streamline identification and generation of bioactive peptides.

  6. Local actions of angiotensin II: quantitative in vitro autoradiographic localization of angiotensin II receptor binding and angiotensin converting enzyme in target tissues

    SciTech Connect

    Chai, S.Y.; Allen, A.M.; Adam, W.R.; Mendelsohn, F.A.

    1986-01-01

    In order to gain insight into the local actions of angiotensin II (ANG II) we have determined the distribution of a component of the effector system for the peptide, the ANG II receptor, and that of an enzyme-catalysing ANG II formation, angiotensin converting enzyme (ACE), by in vitro autoradiography in several target tissues. The superagonist ANG II analog, /sup 125/I(Sar1)ANG II, or the antagonist analog, /sup 125/I(Sar1,Ile8)ANG II, were used as specific radioligands for ANG II receptors. A derivative of the specific ACE inhibitor, lysinopril, called /sup 125/I-351A, was used to label ACE in tissues. In the adrenal, a high density of ANG II receptors occurs in the glomerulosa zone of the cortex and in the medulla. ACE is also localized in these two zones, indicating that local production of ANG II may occur close to its sites of action in the zona glomerulosa and adrenal medulla. In the kidney, a high density of ANG II receptors is associated with glomeruli in the cortex and also with vasa recta bundles in the inner stripe of the outer medulla. ACE is found in very high concentration in deep proximal convoluted tubules of the cortex, while much lower concentrations of the enzyme occur in the vascular endothelium throughout the kidney. In the central nervous system three classes of relationships between ANG II receptors and ACE are observed: In the circumventricular organs, including the subfornical organ and organum vasculosum of the lamina terminalis, a high concentration of both components occurs. Since these structures have a deficient blood-brain barrier, local conversion of circulating angiotensin I (ANG I) to ANG II may contribute to the action of ANG II at these sites.

  7. Application of Structural-Dynamic Approaches Provide Novel Insights Into the Enzymatic Mechanism of the Tumor Necrosis Factor-Alpha Converting Enzyme (TACE)

    SciTech Connect

    Sagi, I.; Milla, M

    2008-01-01

    Zinc dependent metalloproteinases comprise a large family of structurally homologous enzymes with a wide variety of biological roles. Originally described as proteinases involved in extracellular matrix (ECM) catabolism, these enzymes were later found to serve major roles as initiators of signaling pathways in many aspects of biology, ranging from cell proliferation, differentiation and communication, to pathological states associated with tumor metastasis, inflammation, tissue degeneration and cell death. From these enzymes, the tumor necrosis factor-a converting enzyme (TACE) stands out as a central shedding activity mediating the regulated release of a host of cytokines, receptors and other cell surface molecules. Selective drugs targeted at blocking TACE for treatment of rheumatoid arthritis and other disease indications are highly sought. Yet, the structural and chemical knowledge underlying its enzymatic activity is very limited. This is in part due to the fact that the catalytic zinc atom of metalloproteinases is usually spectroscopically silent and hence difficult to study using conventional spectroscopic and analytical tools. Most structural and biochemical studies, as well as medicinal chemistry efforts carried out so far were limited to non-dynamic structure/function characterization. Thus, to date, our mechanistic knowledge comes from theoretical calculations derived from static crystal structures from family members that are highly similar in their amino acid sequence and three-dimensional structure.This review introduces the importance of real-time quantification of biophysical properties and structural kinetic behavior applied to the study of TACE and other zinc metalloproteinases to dissect their molecular mechanisms. The molecular details that link the catalytic chemistry to key kinetic, electronic and structural events have remained elusive because of the difficulties associated with probing time-dependent structure-function aspects of enzymatic

  8. Role of angiotensin-converting enzyme 2 and angiotensin(1-7) in 17beta-oestradiol regulation of renal pathology in renal wrap hypertension in rats.

    PubMed

    Ji, Hong; Menini, Stefano; Zheng, Wei; Pesce, Carlo; Wu, Xie; Sandberg, Kathryn

    2008-05-01

    17beta-Oestradiol (E2)-mediated inhibition of angiotensin-converting enzyme (ACE) protects the E2-replete kidney from the progression of hypertensive renal disease. Angiotensin-converting enzyme 2 (ACE2), a homologue of ACE, counters the actions of ACE by catalysing the conversion of angiotensin II (Ang II) to angiotensin(1-7) [Ang(1-7)]. We investigated E2 regulation of ACE2 in the renal wrap (RW) model of hypertension in rats. After 6 weeks on a high-sodium diet (4% NaCl), the activity of ACE2 was reduced in the renal cortex by 31%, which was mirrored by similar decreases in ACE2 protein (30%) and mRNA expression (36%) in the ovariectomized RW rat (RW-OVX); E2 replacement prevented these effects. The RW-OVX rats exhibited greater renal injury, including 1.7-fold more tubulointerstitial fibrosis and 1.6-fold more glomerulosclerosis than E2-replete females (RW-Intact and RW-OVX+E2). Angiotensin(1-7) infusion prevented these exacerbating effects of ovariectomy on renal pathology; no differences in indicators of renal injury were observed between RW-OVX-Ang(1-7) and RW-Intact rats. These renal protective effects of Ang(1-7) infusion were not attributable to increased ACE2 activity or to changes in heart rate or body weight, since these parameters were unchanged by Ang(1-7) infusion. Furthermore, Ang(1-7) infusion did not attenuate renal injury by reducing mean arterial pressure (MAP), since infusion of the peptide did not lower MAP but rather caused a slight increase during a 6 week chronic treatment for Ang(1-7). These results suggest that E2-mediated upregulation of renal ACE2 and the consequent increased Ang(1-7) production contribute to E2-mediated protection from hypertensive renal disease. These findings have implications for E2-deficient women with hypertensive renal disease and suggest that therapeutics targeted towards increasing ACE2 activity and Ang(1-7) levels will be renal protective.

  9. Angiotensin-converting enzyme (ACE and ACE2) imbalance correlates with the severity of cerulein-induced acute pancreatitis in mice.

    PubMed

    Liu, Ruixia; Qi, Haiyu; Wang, Jing; Wang, Yan; Cui, Lijian; Wen, Yan; Yin, Chenghong

    2014-04-01

    Angiotensin-converting enzyme (ACE) and its effector peptide angiotensin II (Ang II) have been implicated in the pathogenesis of pancreatitis. Angiotensin-converting enzyme 2 (ACE2) degrades Ang II to angiotensin-(1-7) [Ang-(1-7)] and has recently been described to have an antagonistic effect on ACE signalling. However, the specific underlying role of ACE2 in the pathogenesis of severe acute pancreatitis (SAP) is unclear. In the present study, the local imbalance of ACE and ACE2, as well as Ang II and Ang-(1-7) expression, was compared in wild-type (WT) and ACE2 knock-out (KO) or ACE2 transgenic (TG) mice subjected to cerulein-induced SAP. Serum amylase, tumour necrosis factor-α, interleukin (IL)-1β, IL-6 and IL-10 levels and histological morphometry were used to determine the severity of pancreatitis. In WT mice, pancreatic ACE and Ang II and serum Ang II expression increased (P < 0.05), while pancreatic ACE2 and Ang-(1-7) and serum Ang-(1-7) levels were also significantly elevated (P < 0.05) from 2 to 72 h after the onset of SAP. However, the ratio of pancreatic ACE2 to ACE expression was significantly reduced (from 1.46 ± 0.09 to 0.27 ± 0.05, P < 0.001) and paralleled the severity of pancreatitis. The Ace2 KO mice exhibited increased levels of tumour necrosis factor-α, IL-1β, IL-6, multifocal coagulative necrosis and inflammatory infiltrate, and lower levels of serum IL-10 and pancreatic Ang-(1-7) (4.70 ± 2.13 versus 10.87 ± 2.51, P < 0.001) compared with cerulein-treated WT mice at the same time point. Conversely, Ace2 TG mice with normal ACE expression were more resistant to SAP challenge as evidenced by a decreased inflammatory response, attenuated pathological changes and increased survival rates. These data suggest that the ACE2-ACE imbalance plays an important role in the pathogenesis of SAP and that pancreatic ACE2 is an important factor in determining the severity of SAP.

  10. Overexpression of catalase prevents hypertension and tubulointerstitial fibrosis and normalization of renal angiotensin-converting enzyme-2 expression in Akita mice

    PubMed Central

    Shi, Yixuan; Lo, Chao-Sheng; Chenier, Isabelle; Maachi, Hasna; Filep, Janos G.; Ingelfinger, Julie R.; Zhang, Shao-Ling

    2013-01-01

    We investigated the relationship among oxidative stress, hypertension, renal injury, and angiotensin-converting enzyme-2 (ACE2) expression in type 1 diabetic Akita mice. Blood glucose, blood pressure, and albuminuria were monitored for up to 5 mo in adult male Akita and Akita catalase (Cat) transgenic (Tg) mice specifically overexpressing Cat, a key antioxidant enzyme in their renal proximal tubular cells (RPTCs). Same-age non-Akita littermates and Cat-Tg mice served as controls. In separate studies, adult male Akita mice (14 wk) were treated with ANG 1–7 (500 μg·kg−1·day−1 sc) ± A-779, an antagonist of the Mas receptor (10 mg·kg−1·day−1 sc), and euthanized at the age of 18 wk. The left kidneys were processed for histology and apoptosis studies. Renal proximal tubules were isolated from the right kidneys to assess protein and gene expression. Urinary angiotensinogen (AGT), angiotensin II (ANG II), and ANG 1–7 were quantified by specific ELISAs. Overexpression of Cat attenuated renal oxidative stress; prevented hypertension; normalized RPTC ACE2 expression and urinary ANG 1–7 levels (both were low in Akita mice); ameliorated glomerular filtration rate, albuminuria, kidney hypertrophy, tubulointerstitial fibrosis, and tubular apoptosis; and suppressed profibrotic and proapoptotic gene expression in RPTCs of Akita Cat-Tg mice compared with Akita mice. Furthermore, daily administration of ANG 1–7 normalized systemic hypertension in Akita mice, which was reversed by A-779. These data demonstrate that Cat overexpression prevents hypertension and progression of nephropathy and highlight the importance of intrarenal oxidative stress and ACE2 expression contributing to hypertension and renal injury in diabetes. PMID:23552863

  11. Ouabain-like compound changes rapidly on physical exercise in humans and dogs: effects of beta-blockade and angiotensin-converting enzyme inhibition.

    PubMed

    Bauer, Natali; Müller-Ehmsen, Jochen; Krämer, Ulrike; Hambarchian, Njde; Zobel, Carsten; Schwinger, Robert H G; Neu, Horst; Kirch, Ulrike; Grünbaum, Ernst-Günther; Schoner, Wilhelm

    2005-05-01

    Ouabain, an inhibitor of the sodium pump, has been identified as a constituent of bovine adrenal glands. We were interested whether the release of this cardiotonic steroid is stimulated by physical exercise. Hence, athletes and healthy dogs were subjected to ergometry. Ouabain-like compound (OLC) was measured in venous blood by enzyme-linked immunosorbent assay as well as by (86)Rb+ uptake inhibition (as ouabain equivalents). OLC increased in venous blood of athletes after 15 minutes of ergometry from 2.5+/-0.5 to 86.0+/-27.2 nmol/L (n=51; P<0.001), as did the concentration of a circulating inhibitor of the sodium pump from 7.3+/-1.7 to 129.8+/-51 nmol/L (ouabain equivalents, P<0.05). Half-maximal increase in heart rate and systolic blood pressure occurred at 5.1+/-1.2 nmol/L and at 30+/-1 nmol/L OLC, respectively. On rest, OLC decreased in humans and dogs with a half-life of 3 to 5 minutes. In beagles exposed to moderate exercise on a treadmill for 13 minutes, levels of OLC increased 46-fold (from 3.7+/-0.8 to 166.9+/-91.8 nmol/L; n=6; P<0.005). This effect was suppressed when the dogs had been treated for 3 weeks with the beta1-adrenergic receptor blocker atenolol or the angiotensin-converting enzyme inhibitor benazepril. We conclude that OLC changes rapidly during exercise and is under the control of norepinephrine and angiotensin II.

  12. Glycogen phosphorylase and its converter enzymes in haemolysates of normal human subjects and of patients with type VI glycogen-storage disease. A study of phosphorylase kinase deficiency.

    PubMed Central

    Lederer, B; Van Hoof, F; Van den Berghe, G; Hers, H

    1975-01-01

    1. The properties of phosphorylase a, phosphorylase b, phosphorylase kinase and phosphorylase phosphatase present in a human haemolysate were investigated. The two forms of phosphorylase have the same affinity for glucose 1-phosphate but greatly differ in Vmax. Phosphorylase b is only partially stimulated by AMP, since, in the presence of the nucleotide, it is about tenfold less active than phosphorylase a. In a fresh human haemolysate phosphorylase is mostly in the b form; it is converted into phosphorylase a by incubation at 20degreesC, and this reaction is stimulated by glycogen and cyclic AMP. Once activated, the enzyme can be inactivated after filtration of the haemolysate on Sephadex G-25. This inactivation is stimulated by caffeine and glucose and inhibited by AMP and fluoride. The phosphorylase kinase present in the haemolysate can also be measured by the rate of activation of added muscle phosphorylase b, on addition of ATP and Mg2+. 2. The activity of phosphorylase kinase was measured in haemolysates obtained from a series of patients who had been classified as suffering from type VI glycogenosis. In nine patients, all boys, an almost complete deficiency of phosphorylase kinase was observed in the haemolysate and, when it could be assayed, in the liver. A residual activity, about 20% of normal, was found in the leucocyte fraction, whereas the enzyme activity was normal in the muscle. These patients suffer from the sex-linked phosphorylase kinase deficiency previously described by others. Two pairs of siblings, each time brother and sister, displayed a partial deficiency of phosphorylase kinase in the haemolysate and leucocytes and an almost complete deficiency in the liver. This is considered as being the autosomal form of phosphorylase kinase deficiency. Other patients were characterized by a low activity of total (a+b) phosphorylase and a normal or high activity of phosphorylase kinase in their haemolysate. PMID:168880

  13. High throughput and rapid screening of marine protein hydrolysates enriched in peptides with angiotensin-I-converting enzyme inhibitory activity by capillary electrophoresis.

    PubMed

    He, Hai-Lun; Chen, Xiu-Lan; Wu, Hao; Sun, Cai-Yun; Zhang, Yu-Zhong; Zhou, Bai-Cheng

    2007-12-01

    Twelve kinds of marine protein materials, including fish, shrimp, seashell, algae and seafood wastes were selected for the hydrolysis using four different proteases. The IC(50) values for angiotensin-converting enzyme (ACE) inhibitory activity of 48 hydrolysates were rapidly determined by capillary electrophoresis (CE). The values ranged from 0.17 to 501.7mg/ml, and were affected by both the marine protein resources and the selected proteases. Hydrolysates of the lowest IC(50) values were from shrimp (Acetes chinensis), shark meat, mackerel bone, Polysiphonia urceolata and Spirulina platensis, indicating these five kinds of marine food proteins contained beneficial materials for the production of ACE inhibitory peptides by proteolysis. The hydrolysates obtained using proteases Protamex and SM98011 had lower IC(50) values, showing these two proteases were superior to others. The CE method achieved the same sensitivity as the high performance liquid chromatography (HPLC) method. However, the CE method was faster and, as a result, more economical. Therefore, CE had potential for rapid screening of marine protein hydrolysates enriched in ACE inhibitory peptides.

  14. Effects of Metabolites Produced from (-)-Epigallocatechin Gallate by Rat Intestinal Bacteria on Angiotensin I-Converting Enzyme Activity and Blood Pressure in Spontaneously Hypertensive Rats.

    PubMed

    Takagaki, Akiko; Nanjo, Fumio

    2015-09-23

    Inhibitory activity of angiotensin I-converting enzyme (ACE) was examined with (-)-epigallocatechin gallate (EGCG) metabolites produced by intestinal bacteria, together with tea catechins. All of the metabolites showed ACE inhibitory activities and the order of IC50 was hydroxyphenyl valeric acids > 5-(3,4,5-trihydroxyphenyl)-γ-valerolactone (1) > trihydroxyphenyl 4-hydroxyvaleric acid ≫ dihydroxyphenyl 4-hydroxyvaleric acid ≫ 5-(3,5-dihydroxyphenyl)-γ-valerolactone (2). Among the catechins, galloylated catechins exhibited stronger ACE inhibitory activity than nongalloylated catechins. Furthermore, the effects of a single oral intake of metabolites 1 and 2 on systolic blood pressure (SBP) were examined with spontaneously hypertensive rats (SHR). Significant decreases in SBP were observed between 2 h after oral administration of 1 (150 mg/kg in SHR) and the control group (p = 0.002) and between 4 h after administration of 2 (200 mg/kg in SHR) and the control group (p = 0.044). These results suggest that the two metabolites have hypotensive effects in vivo.

  15. Distribution of Angiotensin-1 Converting Enzyme Insertion/Deletion and α-Actinin-3 Codon 577 Polymorphisms in Turkish Male Soccer Players.

    PubMed

    Ulucan, Korkut; Sercan, Canan; Biyikli, Türker

    2015-01-01

    Angiotensin-1 converting enzyme (ACE) gene and α-actinin-3 (ACTN3) gene polymorphisms are considered to be the most important candidate genes for genetic predisposition to human athletic performance. In the present study, we aimed to analyze the distribution of ACE and ACTN3 polymorphisms for the first time in male Turkish soccer players. In this prospective study, our cohort consisted of 25 professional players, all with Turkish ancestry. Polymerase chain reaction (PCR)-restriction length polymorphism was used for the characterization of the genotype of ACTN3 and single PCR for ACE. For ACE genotype, 16%, 44%, and 40% of the players had insertion/insertion (II), insertion/deletion (ID), and deletion/deletion (DD) genotypes, respectively, whereas 20% had XX, 36% had RX, and 44% had RR genotypes for ACTN3. When we examined the allelic percentages, for ACE, D allele was recorded as 62 and I as 38, and for ACTN3, R allele was 62 and X was 38. Our results were in agreement with the previous reports, indicating the presence of ACTN3 D and ACE X allele in soccer players. We suggest that ACE and ACTN3 genotypes are important biomarkers for genetic counseling for the individuals who are prone to be successful soccer players.

  16. Separation and Characterization of Angiotensin I Converting Enzyme (ACE) Inhibitory Peptides from Saurida elongata Proteins Hydrolysate by IMAC-Ni2+

    PubMed Central

    Sun, Lixia; Wu, Shanguang; Zhou, Liqin; Wang, Feng; Lan, Xiongdiao; Sun, Jianhua; Tong, Zhangfa; Liao, Dankui

    2017-01-01

    Lizard fish protein hydrolysates (LFPH) were prepared from Lizard fish (Saurida elongata) proteins possessing powerful angiotensin I converting enzyme (ACE) inhibitory activity and the fraction (LFPH-I) with high ACE inhibitory activity was obtained through ultrafiltration. The active Fraction (F2) was isolated from LFPH-I using immobilized metal affinity chromatography (IMAC-Ni2+). Analysis of amino acid levels revealed that F2 eluted from IMAC was enriched in Met, His, Tyr, Pro, Ile, and Leu compared to the crude peptide LFPH-I. F2 with the high ACE inhibitory activity (IC50 of 0.116 mg·mL−1) was further separated by a reverse-phase column to yield a novel ACE inhibitory peptide with IC50 value of 52 μM. The ACE inhibitory peptide was identified as Arg-Tyr-Arg-Pro, RYRP. The present study demonstrated that IMAC may be a useful tool for the separation of ACE inhibitory peptides from protein hydrolysate. PMID:28212269

  17. Inhibition of central angiotensin converting enzyme ameliorates scopolamine induced memory impairment in mice: role of cholinergic neurotransmission, cerebral blood flow and brain energy metabolism.

    PubMed

    Tota, Santoshkumar; Nath, Chandishwar; Najmi, Abul Kalam; Shukla, Rakesh; Hanif, Kashif

    2012-06-15

    Evidences indicate that inhibition of central Renin angiotensin system (RAS) ameliorates memory impairment in animals and humans. Earlier we have reported involvement of central angiotensin converting enzyme (ACE) in streptozotocin induced neurodegeneration and memory impairment. The present study investigated the role of central ACE in cholinergic neurotransmission, brain energy metabolism and cerebral blood flow (CBF) in model of memory impairment induced by injection of scopolamine in mice. Perindopril (0.05 and 0.1 mg/kg, PO) was given orally for one week before administration of scopolamine (3mg/kg, IP). Then, memory function was evaluated by Morris water maze and passive avoidance tests. CBF was measured by laser Doppler flowmetry. Biochemical and molecular parameters were estimated after the completion of behavioral studies. Scopolamine caused impairment in memory which was associated with reduced CBF, acetylcholine (ACh) level and elevated acetylcholinesterase (AChE) activity and malondialdehyde (MDA) level. Perindopril ameliorated scopolamine induced amnesia in both the behavioral paradigms. Further, perindopril prevented elevation of AChE and MDA level in mice brain. There was a significant increase in CBF and ACh level in perindopril treated mice. However, scopolamine had no significant effect on ATP level and mRNA expression of angiotensin receptors and ACE in cortex and hippocampus. But, perindopril significantly decreased ACE activity in brain without affecting its mRNA expression. The study clearly showed the interaction between ACE and cholinergic neurotransmission and beneficial effect of perindopril can be attributed to improvement in central cholinergic neurotransmission and CBF.

  18. Renal tubular angiotensin converting enzyme is responsible for nitro-L-arginine methyl ester (L-NAME)-induced salt sensitivity.

    PubMed

    Giani, Jorge F; Eriguchi, Masahiro; Bernstein, Ellen A; Katsumata, Makoto; Shen, Xiao Z; Li, Liang; McDonough, Alicia A; Fuchs, Sebastien; Bernstein, Kenneth E; Gonzalez-Villalobos, Romer A

    2017-04-01

    Renal parenchymal injury predisposes to salt-sensitive hypertension, but how this occurs is not known. Here we tested whether renal tubular angiotensin converting enzyme (ACE), the main site of kidney ACE expression, is central to the development of salt sensitivity in this setting. Two mouse models were used: it-ACE mice in which ACE expression is selectively eliminated from renal tubular epithelial cells; and ACE 3/9 mice, a compound heterozygous mouse model that makes ACE only in renal tubular epithelium from the ACE 9 allele, and in liver hepatocytes from the ACE 3 allele. Salt sensitivity was induced using a post L-NAME salt challenge. While both wild-type and ACE 3/9 mice developed arterial hypertension following three weeks of high salt administration, it-ACE mice remained normotensive with low levels of renal angiotensin II. These mice displayed increased sodium excretion, lower sodium accumulation, and an exaggerated reduction in distal sodium transporters. Thus, in mice with renal injury induced by L-NAME pretreatment, renal tubular epithelial ACE, and not ACE expression by renal endothelium, lung, brain, or plasma, is essential for renal angiotensin II accumulation and salt-sensitive hypertension.

  19. Sulfhydryl angiotensin-converting enzyme inhibitor promotes endothelial cell survival through nitric-oxide synthase, fibroblast growth factor-2, and telomerase cross-talk.

    PubMed

    Donnini, Sandra; Terzuoli, Erika; Ziche, Marina; Morbidelli, Lucia

    2010-03-01

    The protective effect exerted by angiotensin-converting enzyme inhibitors (ACEI) in cardiovascular diseases caused by endothelial injury and aging has been attributed to the restoration of endothelial cell functions. Recently, we demonstrated a central role of the fibroblast growth factor-2 (FGF-2)/FGF receptor-1 system in mediating the acquisition of an angiogenic phenotype in coronary microvascular endothelium exposed to ACEI. Here, we report on the rescuing effect of ACEI on impaired endothelium and the intracellular signaling mechanisms that lead endothelial cells to enter apoptosis and to senesce. Conditions mimicking pathological cell damage (serum deprivation) lead to endothelial apoptosis as evidenced by increased caspase-3 activity. ACEI enhanced cell survival through activation of prosurvival and antiaging signals involving Akt phosphorylation, endothelial nitric-oxide synthase (eNOS) expression and activation, FGF-2 and telomerase catalytic subunit (TERT) up-regulation, and delayed senescence. In microvascular endothelial cells exposed to ACEI, Akt/eNOS pathway-dependent FGF-2 was necessary for gene transcription of TERT. These protective effects were particularly evident for sulfhydryl-containing ACEI (zofenoprilat), which were reported to exhibit potent antioxidant effects. In conclusion, ACEI with antioxidant properties up-regulate eNOS, FGF-2, and TERT mRNA, which favor endothelial cell survival and prolong their lifespan, thus restoring endothelial cell functions after vascular damage. These effects could explain the beneficial effects of these drugs in various cardiovascular diseases associated with endothelial injury and aging.

  20. Angiotensin-converting enzyme insertion/deletion polymorphism and susceptibility to allergic rhinitis in Chinese populations: a systematic review and meta-analysis.

    PubMed

    Huang, Ruo-Fei; Dong, Pin; Zhang, Tian-Zhen; Ying, Xin-Jiang; Hu, Hua

    2016-02-01

    In view of the controversies surrounding the angiotensin-converting enzyme (ACE)-allergic rhinitis (AR) association, a systematic review and meta-analysis of the ACE genetic association studies of AR was performed in Chinese populations. PubMed, Springer Link, OvidSP, Chinese biomedical database, Chinese national knowledge infrastructure, Chinese VIP and Wanfang databases were searched for related studies. A total of 4 studies including 415 AR patients and 309 controls were involved in this meta-analysis. Overall, significant association was found between ACE I/D polymorphism and AR risk when all studies in Chinese populations pooled into the meta-analysis (allele, OR 1.50, 95 % CI 1.19-1.90; homozygous, OR 2.59, 95 % CI 1.52-4.41, recessive, OR 2.05, 95 % CI 1.27-3.32). In the subgroup analysis by ethnicity, ACE I/D polymorphism was associated with significant elevated risks of AR in Chinese Han under homozygous and recessive models (homozygous, OR 4.36, 95 % CI 1.76-10.82, recessive, OR 2.51, 95 % CI 1.18-5.34). In conclusion, this meta-analysis provides the evidence that ACE I/D polymorphism may contribute to the AR development in Chinese populations and studies with large sample size and wider spectrum of population are warranted to verify this finding.

  1. Green asparagus (Asparagus officinalis) prevented hypertension by an inhibitory effect on angiotensin-converting enzyme activity in the kidney of spontaneously hypertensive rats.

    PubMed

    Sanae, Matsuda; Yasuo, Aoyagi

    2013-06-12

    Green asparagus (Asparagus officinalis) is known to be rich in functional components. In the present study, spontaneously hypertensive rats (SHR) were used to clarify whether green asparagus prevents hypertension by inhibition of angiotensin-converting enzyme (ACE) activity. Six-week-old male SHR were fed a diet with (AD group) or without (ND group) 5% asparagus for 10 weeks. Systolic blood pressure (SBP) (AD: 159 ± 4.8 mmHg, ND: 192 ± 14.7 mmHg), urinary protein excretion/creatinine excretion, and ACE activity in the kidney were significantly lower in the AD group compared with the ND group. Creatinine clearance was significantly higher in the AD group compared with the ND group. In addition, ACE inhibitory activity was observed in a boiling water extract of asparagus. The ACE inhibitor purified and isolated from asparagus was identified as 2″-hydroxynicotianamine. In conclusion, 2″-hydroxynicotianamine in asparagus may be one of the factors inhibiting ACE activity in the kidney, thus preventing hypertension and preserving renal function.

  2. Short communication: Inhibition of angiotensin 1-converting enzyme by peptides derived from variants of bovine β-casein upon apical exposure to a Caco-2 cell monolayer.

    PubMed

    Petrat-Melin, Bjørn; Le, Thao T; Møller, Hanne S; Larsen, Lotte B; Young, Jette F

    2017-02-01

    This study investigated the consequence of genetically contingent amino acid substitutions in bovine β-casein (CN) genetic variants A(1), A(2), B, and I on the structure and bioactive potential of peptides following in vitro digestion. The β-CN variants were digested in vitro using pepsin and pancreatin, and a peptide profile was obtained by liquid chromatography tandem mass spectrometry, revealing among others, the β-casomorphin precursor peptides VYPFPGPIHN and VYPFPGPIPN, derived from variant A(1)/B and from A(2)/I, respectively. These 2 peptides were synthesized and assessed for angiotensin 1-converting enzyme (ACE) inhibitory capacity before and after incubation with a monolayer of Caco-2 intestinal cells. The VYPFPGPIHN was a stronger ACE inhibitor than VYPFPGPIPN, with the concentration needed to reach half-maximal inhibition (IC50) of 123 ± 14.2 μM versus 656 ± 7.6 μM. Exposure to a Caco-2 intestinal cell monolayer did not affect ACE inhibition by VYPFPGPIHN, but resulted in an almost 2-fold increase in inhibition by VYPFPGPIPN after incubation. Subsequent tandem mass spectrometric analysis identified the truncated peptide VYPFPGPIP, suggesting hydrolysis by a cell membrane associated peptidase. Thus, genetic variation in bovine β-CN results in the generation of peptides that differ in bioactivity, and are differently affected by intestinal brush border peptidases.

  3. Fermentation characteristics and angiotensin I-converting enzyme-inhibitory activity of Lactobacillus helveticus isolate H9 in cow milk, soy milk, and mare milk.

    PubMed

    Wang, Jicheng; Li, Changkun; Xue, Jiangang; Yang, Jie; Zhang, Qing; Zhang, Heping; Chen, Yongfu

    2015-06-01

    Lactobacillus helveticus isolate H9 demonstrated high angiotensin I-converting enzyme (ACE)-inhibitory activity in previous research. Here, we evaluated the fermentation characteristics (pH, titratable acidity, free amino nitrogen, and viable bacterial counts), ACE-inhibitory activity, and contents of Val-Pro-Pro (VPP) and Ile-Pro-Pro (IPP) peptides of stored yogurt (4°C for 28 d) fermented by L. helveticus isolate H9 (initially inoculated at 4 concentrations), from cow, mare, and soy milks. During storage, the pH and titratable acidity remained stable in yogurts produced from all milk types and all inoculation concentrations. The viable bacterial counts in all stored yogurts ranged between 10(6.72) and 10(8.59) cfu/g. The highest ACE-inhibitory activity (70.9-74.5%) was achieved at inoculation concentrations of 5×10(6) cfu/mL. The ACE-inhibitory tripeptides VPP and IPP as determined by ultra-performance liquid chromatography-tandem mass spectrometry were not produced in yogurt made from soy milk or mare milk. These evaluations indicate that L. helveticus H9 has good probiotic properties and would be a promising candidate for production of fermented food with probiotic properties.

  4. Colon cancer cell invasion is promoted by protein kinase CK2 through increase of endothelin-converting enzyme-1c protein stability.

    PubMed

    Niechi, Ignacio; Silva, Eduardo; Cabello, Pablo; Huerta, Hernan; Carrasco, Valentina; Villar, Paulina; Cataldo, Luis Rodrigo; Marcelain, Katherine; Armisen, Ricardo; Varas-Godoy, Manuel; Fernandez, Cristina; Tapia, Julio C

    2015-12-15

    Endothelin-converting enzyme-1c (ECE-1c) is a membrane metalloprotease involved in endothelin-1 synthesis, which has been shown in vitro to have a role in breast, ovary and prostate cancer cell invasion. N-terminal end of ECE-1c displays three putative phosphorylation sites for the protein kinase CK2. We studied whether CK2 phosphorylates N-terminal end of ECE-1c as well as whether this has a role in migration and invasion of colon cancer cells. CK2 phosphorylated the N-terminal end of ECE-1c and this was precluded upon inhibition of CK2. Inhibition also led to diminished protein levels of both endogen ECE-1 or GFP-fused N-terminal end of ECE-1c in 293T embryonic and DLD-1 colon cancer cells, which highlighted the importance of this motif on UPS-dependent ECE-1c degradation. Full-length ECE-1c mutants designed either to mimic or abrogate CK2-phosphorylation displayed increased or decreased migration/invasion of colon cancer cells, respectively. Moreover, ECE-1c overexpression or its silencing with a siRNA led to increased or diminished cell migration/invasion, respectively. Altogether, these data show that CK2-increased ECE-1c protein stability is related to augmented migration and invasion of colon cancer cells, shedding light on a novel mechanism by which CK2 may promote malignant progression of this disease.

  5. Colon cancer cell invasion is promoted by protein kinase CK2 through increase of endothelin-converting enzyme-1c protein stability

    PubMed Central

    Niechi, Ignacio; Silva, Eduardo; Cabello, Pablo; Huerta, Hernan; Carrasco, Valentina; Villar, Paulina; Cataldo, Luis Rodrigo; Marcelain, Katherine; Armisen, Ricardo; Varas-Godoy, Manuel; Fernandez, Cristina; Tapia, Julio C.

    2015-01-01

    Endothelin-converting enzyme-1c (ECE-1c) is a membrane metalloprotease involved in endothelin-1 synthesis, which has been shown in vitro to have a role in breast, ovary and prostate cancer cell invasion. N-terminal end of ECE-1c displays three putative phosphorylation sites for the protein kinase CK2. We studied whether CK2 phosphorylates N-terminal end of ECE-1c as well as whether this has a role in migration and invasion of colon cancer cells. CK2 phosphorylated the N-terminal end of ECE-1c and this was precluded upon inhibition of CK2. Inhibition also led to diminished protein levels of both endogen ECE-1 or GFP-fused N-terminal end of ECE-1c in 293T embryonic and DLD-1 colon cancer cells, which highlighted the importance of this motif on UPS-dependent ECE-1c degradation. Full-length ECE-1c mutants designed either to mimic or abrogate CK2-phosphorylation displayed increased or decreased migration/invasion of colon cancer cells, respectively. Moreover, ECE-1c overexpression or its silencing with a siRNA led to increased or diminished cell migration/invasion, respectively. Altogether, these data show that CK2-increased ECE-1c protein stability is related to augmented migration and invasion of colon cancer cells, shedding light on a novel mechanism by which CK2 may promote malignant progression of this disease. PMID:26543229

  6. Investigation of lactic acid bacterial strains for meat fermentation and the product's antioxidant and angiotensin-I-converting-enzyme inhibitory activities.

    PubMed

    Takeda, Shiro; Matsufuji, Hisashi; Nakade, Koji; Takenoyama, Shin-Ichi; Ahhmed, Abdulatef; Sakata, Ryoichi; Kawahara, Satoshi; Muguruma, Michio

    2016-08-02

    In the lactic acid bacteria (LAB) strains screened from our LAB collection, Lactobacillus (L.) sakei strain no. 23 and L. curvatus strain no. 28 degraded meat protein and tolerated salt and nitrite in vitro. Fermented sausages inoculated strains no. 23 and no. 28 showed not only favorable increases in viable LAB counts and reduced pH, but also the degradation of meat protein. The sausages fermented with these strains showed significantly higher antioxidant activity than those without LAB or fermented by each LAB type strain. Angiotensin-I-converting-enzyme (ACE) inhibitory activity was also significantly higher in the sausages fermented with strain no. 23 than in those fermented with the type strain. Higher ACE inhibitory activity was also observed in the sausages fermented with strain no. 28, but did not differ significantly from those with the type strain. An analysis of the proteolysis and degradation products formed by each LAB in sausages suggested that those bioactivities yielded fermentation products such as peptides. Therefore, LAB starters that can adequately ferment meat, such as strains no. 23 and no. 28, should contribute to the production of bioactive compounds in meat products.

  7. Effects of cocoa extract and dark chocolate on angiotensin-converting enzyme and nitric oxide in human endothelial cells and healthy volunteers--a nutrigenomics perspective.

    PubMed

    Persson, Ingrid A L; Persson, Karin; Hägg, Staffan; Andersson, Rolf G G

    2011-01-01

    Evidence suggests that cocoa from the bean of Theobroma cacao L. has beneficial effects on cardiovascular disease. The aim of this study was to investigate if cocoa extract and dark chocolate influence angiotensin-converting enzyme (ACE) and nitric oxide (NO) in human endothelial cells (in vitro) and in healthy volunteers (in vivo). ACE activity was analyzed with a commercial radioenzymatic assay and measured in human endothelial cells from umbilical veins (HUVEC) after 10 minutes of incubation with cocoa extract. NO was measured after 24 hours of incubation. ACE activity and NO were measured at baseline and after 30, 60, and 180 minutes in 16 healthy volunteers after a single intake of 75 g of dark chocolate containing 72% cocoa. Significant inhibition of ACE activity (P < 0.01) and significant increase of NO (P < 0.001) were seen in HUVEC. In the study subjects, a significant inhibition of ACE activity (mean 18%) 3 hours after intake of dark chocolate was seen, but no significant change in NO was seen. According to ACE genotype, significant inhibition of ACE activity was seen after 3 hours in individuals with genotype insertion/insertion and deletion/deletion (mean 21% and 28%, respectively). Data suggest that intake of dark chocolate containing high amount of cocoa inhibits ACE activity in vitro and in vivo.

  8. Registered report: The common feature of leukemia-associated IDH1 and IDH2 mutations is a neomorphic enzyme activity converting alpha-ketoglutarate to 2-hydroxyglutarate

    PubMed Central

    Fiehn, Oliver; Showalter, Megan Reed; Schaner-Tooley, Christine E

    2016-01-01

    The Reproducibility Project: Cancer Biology seeks to address growing concerns about reproducibility in scientific research by conducting replications of selected experiments from a number of high-profile papers in the field of cancer biology. The papers, which were published between 2010 and 2012, were selected on the basis of citations and Altmetric scores (Errington et al., 2014). This Registered Report describes the proposed replication plan of key experiments from “The common feature of leukemia-associated IDH1 and IDH2 mutations is a neomorphic enzyme activity converting alpha-ketoglutarate to 2-hydroxyglutarate” by Ward and colleagues, published in Cancer Cell in 2010 (Ward et al., 2010). The experiments that will be replicated are those reported in Figures 2, 3 and 5. Ward and colleagues demonstrate the mutations in isocitrate dehydrogenase 2 (IDH2), commonly found in acute myeloid leukemia (AML), abrogate the enzyme’s wild-type activity and confer to the mutant neomorphic activity that produces the oncometabolite 2-hydroxyglutarate (2-HG) (Figures 2 and 3). They then show that elevated levels of 2-HG are correlated with mutations in IDH1 and IDH2 in AML patient samples (Figure 5). The Reproducibility Project: Cancer Biology is a collaboration between the Center for Open Science and Science Exchange and the results of the replications will be published by eLife. DOI: http://dx.doi.org/10.7554/eLife.12626.001 PMID:26943899

  9. In vitro antidiabetic and inhibitory potential of turmeric (Curcuma longa L) rhizome against cellular and LDL oxidation and angiotensin converting enzyme.

    PubMed

    Lekshmi, P C; Arimboor, Ranjith; Nisha, V M; Menon, A Nirmala; Raghu, K G

    2014-12-01

    Turmeric (Curcuma longa L) rhizome extracts were evaluated for their antidiabetic, antihypertensive and antioxidant potentials. α-Glucosidase (0.4 μg/mL) and α-amylase (0.4 μg/mL) inhibitory potential of turmeric ethyl acetate extract was significantly higher than those of the reference drug acarbose (17.1 μg/mL and 290.6 μg/mL respectively). Protein glycation inhibitory potential of ethyl acetate extract was 800 times higher than that of ascorbic acid. High potential of ethyl acetate extract to scavenge free radicals and to reduce LDL oxidation and cellular oxidative stress was also revealed. The positive correlation obtained between the free radical scavenging capacity of the extracts and their antiglycation potential further confirmed the role of antioxidants in controlling glycation reactions. Ethyl acetate extract was also found as effective in reducing hypertension by inhibiting angiotensin converting enzyme (ACE). Antidiabetic, ACE inhibitory and antioxidant capacities of the extracts were in the order of their curcumin contents.

  10. Patients With Newly Diagnosed Hypertension Treated With the Renin Angiotensin Receptor Blocker Azilsartan Medoxomil vs Angiotensin-Converting Enzyme Inhibitors: The Prospective EARLY Registry.

    PubMed

    Schmieder, Roland E; Potthoff, Sebastian A; Bramlage, Peter; Baumgart, Peter; Mahfoud, Felix; Buhck, Hartmut; Ouarrak, Taoufik; Ehmen, Martina; Senges, Jochen; Gitt, Anselm K

    2015-12-01

    For patients with newly diagnosed hypertension, angiotensin-converting enzyme (ACE) inhibitors or angiotensin receptor blockers (ARBs) are usually the first-line therapies. There is, however, no real-life data regarding the relative clinical effectiveness and tolerability of either drug class. The prospective registry, Treatment With Azilsartan Compared to ACE Inhibitors in Antihypertensive Therapy (EARLY), was conducted to evaluate the effectiveness of the ARB azilsartan medoxomil (AZL-M) vs ACE inhibitors in real-world patients. Of the 1153 patients with newly diagnosed hypertension who were included in the registry, 789 were prescribed AZL-M and 364 were prescribed an ACE inhibitor. After multivariate adjustment, AZL-M was found to provide superior blood pressure reduction and better target blood pressure (<140/90 mm Hg) achievement. The proportion of patients with adverse events was not statistically different between groups. The authors conclude that in newly diagnosed hypertensive patients, AZL-M provides superior blood pressure control with a similar safety profile compared with ACE inhibitors.

  11. Genetic Polymorphism of Angiotensin Converting Enzyme and Risk of Coronary Restenosis after Percutaneous Transluminal Coronary Angioplasties: Evidence from 33 Cohort Studies

    PubMed Central

    Chen, Lingling; Dong, Zhibing; Chen, Yunpeng; Li, Chenguang; Zhong, Xin; Lin, Wenhui; Zhang, Jifu

    2013-01-01

    Background In the past decade, a number of cohort studies studies have been carried out to investigate the relationship between the insertion/deletion polymorphism of the gene encoding angiotensin-converting enzyme and risk of restenosis after percutaneous transluminal coronary angioplasties in patients. However, these studies have yielded contradictory results. Genetic association studies addressing this issue are frequently hampered by insufficient power. We therefore performed a meta-analysis of the published studies to clarify this inconsistency and to establish a comprehensive picture of the relationship between ACE I/D polymorphism and post-PTCA restenosis risk. Methods Databases including Pubmed, EMBASE, ISI Web of Science, EBSCO, Cochrane Library databases and CNKI were searched to find relevant studies. Odds ratios (ORs) with 95% confidence intervals (CIs) were used to assess the strength of association. The random-effects model was applied, addressing heterogeneity and publication bias. Results A total of 33 cohort studies involving 11,099 subjects were included. In a combined analysis, the OR for post-PTCA restenosis of the ACE DD genotype was 1.61 (95% CI: 1.27–2.04; P<10−5). In the subgroup analysis by intervention, significantly increased risks were also found in PTCA-stent and PTCA-balloon for the DD genotype of the polymorphism. Conclusions Our meta-analysis showed that the DD genotype of ACE I/D polymorphism was significantly associated with increased risk of restenosis, particularly for PTCA-stent. PMID:24098690

  12. Influence of the Angiotensin Converting Enzyme Insertion or Deletion Genetic Variant and Coronary Restenosis Risk: Evidence Based on 11,193 Subjects

    PubMed Central

    Pan, Yang; Wang, Fang; Qiu, Qin; Ding, Ren; Zhao, Baolong; Zhou, Hua

    2013-01-01

    The insertion/deletion (I/D) polymorphism of the gene encoding angiotensin converting enzyme is a controversial risk factor for restenosis after percutaneous transluminal coronary angioplasties (PTCA) in patients. Genetic association studies can be problematic to reproduce due to insufficient power, phenotypic heterogeneity, population stratification, small effect of the variant and even publication biases. To derive a more precise estimation of the relationship as well as to quantify the between-study heterogeneity and potential bias, a meta-analysis including 11,193 patients from 33 published cohort studies was performed. In a combined analysis, the summary per-allele odds ratio for restenosis was 1.31 (95% CI: 1.08-1.58, P = 0.006), and 1.22 (95% CI: 0.95-1.56, P = 0.12), for PTCA-stent and PTCA-balloon, respectively. In the subgroup analysis by ethnicity, significantly increased restenosis risks after PTCA-stent were found in Asians for the polymorphism; whereas no significant associations were found among Caucasians. As for restenosis risks after PTCA-balloon, no evidence of any gene-disease association was obtained in the stratified analyses according to ethnicity and study size. In conclusion, this meta-analysis demonstrated that the DD homozygous of ACE I/D polymorphism was significantly associated with elevated restenosis susceptibility after PTCA-stent among Asian populations. PMID:24349507

  13. Angiotensin-converting enzyme inhibition reduces food intake and weight gain and improves glucose tolerance in melanocortin-4 receptor deficient female rats.

    PubMed

    Mul, Joram D; Seeley, Randy J; Woods, Stephen C; Begg, Denovan P

    2013-09-10

    Functional loss of melanocortin-4 receptor (MC4R) activity leads to hyperphagia and an obese, glucose intolerant phenotype. We have previously established that inhibition of angiotensin-converting enzyme (ACE) reduces food intake, body weight and glucose homeostasis in diet-induced obesity. The current study assessed the effect of ACE inhibitor treatment in MC4R-deficient female rats on body weight, adiposity and glucose tolerance. Rats homozygous (HOM) for a loss of function Mc4r mutation had an obese phenotype relative to their wildtype (WT) littermates. Inhibition of ACE for 8weeks produced reductions in body weight gain in both HOM and WT rats; however, food intake was only reduced in HOM rats. Weight loss following ACE inhibitor treatment was specific to fat mass while lean mass was unaffected. HOM rats were severely glucose intolerant and insensitive to exogenous insulin injection, and treatment with an ACE inhibitor improved both glucose tolerance and insulin sensitivity in HOM rats although not fully to that of the level of WT rats. The current study indicates that HOM rats are sensitive to the anorectic effects of ACE inhibition, unlike their WT littermates. This resulted in a more rapid reduction in body weight gain and a more substantial loss of adipose mass in HOM animals, relative to WT animals, treated with an ACE inhibitor. Overall, these data demonstrate that MC4R signaling is not required for weight loss following treatment with an ACE inhibitor.

  14. Combination of six enzymes of a marine Novosphingobium converts the stereoisomers of β-O-4 lignin model dimers into the respective monomers.

    PubMed

    Ohta, Yukari; Nishi, Shinro; Hasegawa, Ryoichi; Hatada, Yuji

    2015-10-19

    Lignin, an aromatic polymer of phenylpropane units joined predominantly by β-O-4 linkages, is the second most abundant biomass component on Earth. Despite the continuous discharge of terrestrially produced lignin into marine environments, few studies have examined lignin degradation by marine microorganisms. Here, we screened marine isolates for β-O-4 cleavage activity and determined the genes responsible for this enzymatic activity in one positive isolate. Novosphingobium sp. strain MBES04 converted all four stereoisomers of guaiacylglycerol-β-guaiacyl ether (GGGE), a structural mimic of lignin, to guaiacylhydroxypropanone as an end metabolite in three steps involving six enzymes, including a newly identified Nu-class glutathione-S-transferase (GST). In silico searches of the strain MBES04 genome revealed that four GGGE-metabolizing GST genes were arranged in a cluster. Transcriptome analysis demonstrated that the lignin model compounds GGGE and (2-methoxyphenoxy)hydroxypropiovanillone (MPHPV) enhanced the expression of genes in involved in energy metabolism, including aromatic-monomer assimilation, and evoked defense responses typically expressed upon exposure to toxic compounds. The findings from this study provide insight into previously unidentified bacterial enzymatic systems and the physiological acclimation of microbes associated with the biological transformation of lignin-containing materials in marine environments.

  15. The use of angiotensin-converting enzyme inhibitors and diuretics is associated with a reduced incidence of impairment on cognition in elderly women.

    PubMed

    Yasar, S; Zhou, J; Varadhan, R; Carlson, M C

    2008-07-01

    The effects of angiotensin-converting enzyme inhibitors (ACE-Is) and diuretics (used as antihypertensive agents) on global and domain-specific cognitive decline were evaluated in 326 non-demented community-dwelling participants over the age of 70 years in the Women's Health and Aging Study II. Time-dependent Cox proportional hazards regression analysis was used for evaluating the association between parameters. The use of ACE-I for more than 3 years was associated with reduced incidence of impairment on Mini-Mental State Examination (MMSE), Trail Making Test-Part A and Part B (TMT, Parts A and B), Hopkins Verbal Learning Test-Immediate Recall (HVLT-I), and Hopkins Verbal Learning Test-Delayed Recall (HVLT-D). The use of diuretics for more than 3 years was associated with reduced incidence of impairment on MMSE, TMT, Parts A and B, HVLT-I, and (HVLT-D). The presence of vascular disease did not make any difference to these effects. Therefore, the use of ACE-Is or diuretics was associated with reduced incidence of impairment of both global and domain-specific cognition in elderly women, and may help delay progression to dementia.

  16. Variations in chemical composition, vasorelaxant and angiotensin I-converting enzyme inhibitory activities of essential oil from aerial parts of Seseli pallasii Besser (Apiaceae).

    PubMed

    Suručić, Relja; Kundaković, Tatjana; Lakušić, Branislava; Drakul, Dragana; Milovanović, Slobodan R; Kovačević, Nada

    2016-12-10

    The present paper describes environmental and seasonal-related chemical composition variations, vasorelaxant and angiotensin I-converting enzyme (ACE) activities of essential oil from aerial parts of Seseli pallasii Besser. The composition was analyzed by GC and GC/MS. Monoterpens were found to be the most abundant chemical class with α-pinene (42.7-48.2%) as the most prevalent component. Seseli pallasi essential oil relaxed isolated endothelium-intact mesenteric arteries rings precontracted with phenylephrine with IC50 = 3.10 nl/ml (IC50 =2.70 μg/ml). Also, S. pallasii essential oil was found to exhibit a dose-dependent ACE inhibitory activity with an IC50 value of 0.33 mg/ml. In silico evaluation of ACE inhibitory activity of the individual components showed that spathulenol exhibited the best binding affinity with ACE, and the lowest binding energy of -7.5 kcal/mol. The results suggested that combination of vasorelaxing and ACE inhibitory effects of the analyzed S. pallasii essential oil might have the potential therapeutic significance in hypertension. This article is protected by copyright. All rights reserved.

  17. Neurotensin-induced Proinflammatory Signaling in Human Colonocytes Is Regulated by β-Arrestins and Endothelin-converting Enzyme-1-dependent Endocytosis and Resensitization of Neurotensin Receptor 1*

    PubMed Central

    Law, Ivy Ka Man; Murphy, Jane E.; Bakirtzi, Kyriaki; Bunnett, Nigel W.; Pothoulakis, Charalabos

    2012-01-01

    The neuropeptide/hormone neurotensin (NT) mediates intestinal inflammation and cell proliferation by binding of its high affinity receptor, neurotensin receptor-1 (NTR1). NT stimulates IL-8 expression in NCM460 human colonic epithelial cells by both MAP kinase- and NF-κB-dependent pathways. Although the mechanism of NTR1 endocytosis has been studied, the relationship between NTR1 intracellular trafficking and inflammatory signaling remains to be elucidated. In the present study, we show that in NCM460 cells exposed to NT, β-arrestin-1 (βARR1), and β-arrestin-2 (βARR2) translocate to early endosomes together with NTR1. Endothelin-converting enzyme-1 (ECE-1) degrades NT in acidic conditions, and its activity is crucial for NTR1 recycling. Pretreatment of NCM460 cells with the ECE-1 inhibitor SM19712 or gene silencing of βARR1 or βARR2 inhibits NT-stimulated ERK1/2 and JNK phosphorylation, NF-κB p65 nuclear translocation and phosphorylation, and IL-8 secretion. Furthermore, NT-induced cell proliferation, but not IL-8 transcription, is attenuated by the JNK inhibitor, JNK(AII). Thus, NTR1 internalization and recycling in human colonic epithelial cells involves βARRs and ECE-1, respectively. Our results also indicate that βARRs and ECE-1-dependent recycling regulate MAP kinase and NF-κB signaling as well as cell proliferation in human colonocytes in response to NT. PMID:22416137

  18. AAV8-Mediated Angiotensin-Converting Enzyme 2 Gene Delivery Prevents Experimental Autoimmune Uveitis by Regulating MAPK, NF-κB and STAT3 Pathways

    PubMed Central

    Qiu, Yiguo; Tao, Lifei; Zheng, Shijie; Lin, Ru; Fu, Xinyu; Chen, Zihe; Lei, Chunyan; Wang, Jiaming; Li, Hongwei; Li, Qiuhong; Lei, Bo

    2016-01-01

    Renin angiotensin system (RAS) is a key hormonal system which regulates the cardiovascular function and is implicated in several autoimmune diseases. With the discovery of the angiotensin-converting enzyme 2 (ACE2), a protective axis of RAS namely ACE2/Ang-(1–7)/Mas that counteracts the deleterious ACE/AngII/AT1R axis has been established. This axis is emerging as a novel target to attenuate ocular inflammation. However, the underlying molecular mechanisms remain unclear. We investigated the hypothesis that enhancing the activity of the protective axis of RAS by subretinal delivery of an AAV8 (Y733F)-ACE2 vector would protect against the ocular inflammation in experimental autoimmune uveitis (EAU) mice through regulating the local immune responses. Our studies demonstrated that increased ACE2 expression exerts protective effects on inflammation in EAU mouse by modulating ocular immune responses, including the differentiation of Th1/Th17 cells and the polarization of M1/M2 macrophages; whereas the systemic immune responses appeared not affected. These effects were mediated by activating the Ang-(1–7)/Mas and inhibiting the MAPK, NF-κB and STAT3 signaling pathways. This proof-of-concept study suggests that activation of ocular ACE2/Ang-(1–7)/Mas axis with AAV gene transfer modulates local immune responses and may be a promising, long-lasting therapeutic strategy for refractory and recurrent uveitis, as well as other inflammatory eye diseases. PMID:27558087

  19. An angiotensin converting enzyme inhibitor, benazepril can be transformed to an active metabolite, benazeprilat, by the liver of dogs with ascitic pulmonary heartworm disease.

    PubMed

    Kitagawa, Hitoshi; Ohba, Yasunori; Kuwahara, Yasuhito; Ohne, Rieko; Kondo, Masahiro; Nakano, Masakazu; Sasaki, Yoshihide; Kitoh, Katsuya

    2003-06-01

    To examine whether an angiotensin converting enzyme (ACE) inhibitor, benazepril, can be transformed to the active metabolite, benazeprilat, by severely injured liver of dogs with ascitic heartworm disease, benazepril hydrochloride was administered orally to dogs once daily for 7 consecutive days at a dose rate of 0.29 mg/kg to 0.63 mg/kg of body weight, and plasma benazepril and benazeprilat concentrations were determined on the 1st and 7th administration days. In 7 dogs with ascitic pulmonary heartworm disease, plasma benazeprilat concentrations tended to be higher than in 7 control dogs both on the 1st and 7th administration days. The peak concentration and area under the concentration-time curve tended to be greater in dogs of the ascites group than in control dogs, but the statistics could not detect significant differences in the time to peak concentration and t(1/2) between the control and ascites groups. Plasma ACE activities decreased after administration of benazepril. In dogs with ascitic heartworm disease, benazepril was readily transformed to benazeprilat by the liver, and was effective for suppression of plasma ACE activity.

  20. Simulated digestion of proanthocyanidins in grape skin and seed extracts and the effects of digestion on the angiotensin I-converting enzyme (ACE) inhibitory activity.

    PubMed

    Fernández, Katherina; Labra, Javiera

    2013-08-15

    This study investigated the effect of in vitro gastrointestinal digestion on the stability and composition of flavan-3-ols from red grape skin and seed extracts (raw and purified, which are high in proanthocyanidins (PAs)). In addition, the effects of digestion on the angiotensin I-converting enzyme (ACE) inhibitory activities of these extracts were evaluated. The extracts were digested with a mixture of pepsin-HCl for 2 h, followed by a 2 h incubation with pancreatin and bile salts including a cellulose dialysis tubing (molecular weight cut-off 12 kDa) at 37°C with shaking in the dark and under N2. Under gastric conditions, the mean degree of polymerisation (mDP) of seed extracts, raw (mDP≈6, p<0.05), and purified (mDP≈10, p<0.05) was stable. The mDP of the raw skin extracts increased from 19 to 25 towards the end of the digestion. The PAs were significantly degraded (up to 80%) during the pancreatic digestion, yielding low-molecular-weight compounds that diffused into the serum-available fraction (mDP≈2). The overall mass transfer coefficient (K) of the seed extracts was 10(-7) m(2)/s. After simulated gastrointestinal digestion, over 80% of ACE inhibition by raw seed and skin extracts was preserved. However, the purified seed and skin extracts lost their ability to inhibit ACE after intestinal digestion.

  1. Angiotensin-converting enzyme labeled with [3H]captopril. Tissue localizations and changes in different models of hypertension in the rat.

    PubMed Central

    Wilson, S K; Lynch, D R; Snyder, S H

    1987-01-01

    In vitro autoradiography with [3H]captopril was used to localize and quantitate angiotensin-converting enzyme (ACE) in various tissues in two-kidney, one-clip (2K-1C) hypertension, one-kidney, one-clip (1K-1C) hypertension, desoxycorticosterone acetate (DOCA)-salt hypertension, and a normotensive control group. There were no significant differences in mean systolic blood pressure among the hypertensive groups. Plasma renin activity (PRA) was highest in the 2K-1C group (6.20 +/- 2.17 ng/ml per h), intermediate in the 1K-1C group (2.19 +/- 0.62 ng/ml per h) and control group (3.20 +/- 0.53 ng/ml per h), and lowest in the DOCA-salt group (0.07 +/- 0.06 ng/ml per h). In the lungs, aorta, mesenteric arteries, and adrenal medulla, ACE labeling was highest in the 2K-1C group, intermediate in the 1K-1C and control groups, and lowest in the DOCA-salt group. ACE levels in these tissues correlated positively with PRA. In the kidney, anterior pituitary, testis, and choroid plexus of the brain, ACE levels correlated negatively with PRA, with lowest ACE levels in the 2K-1C group and highest levels in the DOCA-salt group. In the epididymis, posterior pituitary, and other regions of the brain, ACE levels did not differ significantly among the groups. Images PMID:3040809

  2. Short communication: Potential of Fresco-style cheese whey as a source of protein fractions with antioxidant and angiotensin-I-converting enzyme inhibitory activities.

    PubMed

    Tarango-Hernández, S; Alarcón-Rojo, A D; Robles-Sánchez, M; Gutiérrez-Méndez, N; Rodríguez-Figueroa, J C

    2015-11-01

    Recently, traditional Mexican Fresco-style cheese production has been increasing, and the volume of cheese whey generated represents a problem. In this study, we investigated the chemical composition of Fresco-style cheese wheys and their potential as a source of protein fractions with antioxidant and angiotensin-I-converting enzyme (ACE)-inhibitory activities. Three samples from Fresco, Panela, and Ranchero cheeses whey were physicochemically characterized. Water-soluble extracts were fractionated to obtain whey fractions with different molecular weights: 10-5, 5-3, 3-1 and <1 kDa. The results indicated differences in the lactose, protein, ash, and dry matter contents (% wt/wt) in the different Fresco-style cheese wheys. All whey fractions had antioxidant and ACE-inhibitory activities. The 10-5 kDa whey fraction of Ranchero cheese had the highest Trolox equivalent antioxidant capacity (0.62 ± 0.00 mM), and the 3-1 kDa Panela and Fresco cheese whey fractions showed the highest ACE-inhibitory activity (0.57 ± 0.02 and 0.59 ± 0.04 μg/mL 50%-inhibitory concentration values, respectively). These results suggest that Fresco-style cheese wheys may be a source of protein fractions with bioactivity, and thus could be useful ingredients in the manufacture of functional foods with increased nutritional value.

  3. Changes of proteolysis and angiotensin-I converting enzyme-inhibitory activity in white-brined cheese as affected by adjunct culture and ripening temperature.

    PubMed

    Sahingil, Didem; Hayaloglu, Ali A; Kirmaci, Huseyin A; Ozer, Barbaros; Simsek, Osman

    2014-11-01

    The effects of use of adjunct cultures (Lactobacillus helveticus and Lb. casei) and ripening temperatures (6 or 12 °C) on proteolysis and angiotensin-I converting enzyme (ACE)-inhibitory activity in white-brined cheeses were investigated during 120 d ripening. Proteolysis was monitored by urea-polyacrylamide gel electrophoresis (urea-PAGE) and reversed phase-HPLC (RP-HPLC) of water-insoluble and -soluble fractions of the cheeses, respectively. Urea-PAGE patterns of the samples revealed that the intensities of the bands representing casein fractions decreased in the experimental cheeses, being more pronounced in the cheeses made with adjunct cultures. Similarly, peptide profiles and the concentrations of individual and total free amino acids were influenced by both the adjunct cultures and ripening temperatures. The ACE-inhibitory activity of the water-soluble extracts of the cheeses were higher in the cheeses made using adjunct cultures (especially Lb. helveticus) and ripened at 12 °C. The ACE-inhibitory activity did not decrease during ripening. The contribution of Lb. helveticus to the development of proteolysis and ACE-inhibitory peptide activities were higher than that of Lb. casei. To conclude, the use of Lb. helveticus as adjunct culture in white-brined cheese and ripening at 12 °C would be recommended to obtain white-brined cheese with high ACE-I-inhibitory peptides activity and higher levels of preoteolysis.

  4. Mitochondrial uncoupling proteins regulate angiotensin‐converting enzyme expression: crosstalk between cellular and endocrine metabolic regulators suggested by RNA interference and genetic studies

    PubMed Central

    Maubaret, Cecilia; Pedersen‐Bjergaard, Ulrik; Brull, David J.; Gohlke, Peter; Payne, John R.; World, Michael; Thorsteinsson, Birger; Humphries, Steve E.; Montgomery, Hugh E.

    2015-01-01

    Uncoupling proteins (UCPs) regulate mitochondrial function, and thus cellular metabolism. Angiotensin‐converting enzyme (ACE) is the central component of endocrine and local tissue renin–angiotensin systems (RAS), which also regulate diverse aspects of whole‐body metabolism and mitochondrial function (partly through altering mitochondrial UCP expression). We show that ACE expression also appears to be regulated by mitochondrial UCPs. In genetic analysis of two unrelated populations (healthy young UK men and Scandinavian diabetic patients) serum ACE (sACE) activity was significantly higher amongst UCP3‐55C (rather than T) and UCP2 I (rather than D) allele carriers. RNA interference against UCP2 in human umbilical vein endothelial cells reduced UCP2 mRNA sixfold (P < 0·01) whilst increasing ACE expression within a physiological range (<1·8‐fold at 48 h; P < 0·01). Our findings suggest novel hypotheses. Firstly, cellular feedback regulation may occur between UCPs and ACE. Secondly, cellular UCP regulation of sACE suggests a novel means of crosstalk between (and mutual regulation of) cellular and endocrine metabolism. This might partly explain the reduced risk of developing diabetes and metabolic syndrome with RAS antagonists and offer insight into the origins of cardiovascular disease in which UCPs and ACE both play a role. PMID:27347560

  5. Bioassay-guided preparative separation of angiotensin-converting enzyme inhibitory C-flavone glycosides from Desmodium styracifolium by recycling complexation high-speed counter-current chromatography.

    PubMed

    Zhang, Ying-Qi; Luo, Jian-Guang; Han, Chao; Xu, Jin-Fang; Kong, Ling-Yi

    2015-01-01

    A new strategy of the convergence of high-speed counter-current chromatography (HSCCC) and bioactive assay technique was developed for rapidly screening and separating the angiotensin-converting enzyme (ACE) inhibitors from the aerial parts of Desmodium styracifolium. Bioactivity-guided fractionation of the crude extract was first established to target the bioactive fractions based on HSCCC coupled with in vitro ACE inhibitory assay. Subsequently, the bioactive fractions were further separated by the recycling complexation HSCCC respectively, using 0.10 mol/L copper sulfate in the lower phase of two-phase solvent system composed of n-butanol/water (1:1, v/v). Five C-glycosylflavones, vicenin 2 (1), carlinoside (2), vicenin 1 (3), schaftoside (4) and vicenin 3 (5), were successfully obtained. Their chemical structures were identified using ESI-MS and NMR. All the isolates showed in vitro ACE inhibitory activity with the IC50 values between 33.62 and 58.37 μM. The results demonstrated that the established method was proposed as an excellent strategy to systematically screen and purify active compounds from traditional Chinese medicines.

  6. RNAi-mediated silencing of TNF-α converting enzyme to down-regulate soluble TNF-α production for treatment of acute and chronic colitis.

    PubMed

    Song, Yoonsung; Kim, Ye-Ram; Kim, So Mi; Ul Ain, Qurrat; Jang, Kiseok; Yang, Chul-Su; Kim, Yong-Hee

    2016-10-10

    Elevated level of tumor necrosis factor-α (TNF-α), one of the inflammatory cytokines, is considered to be a potential target for the inflammatory bowel disease (IBD) therapy. Recently, TNF-α converting enzyme (TACE), a sheddase playing an important role in cleaving and releasing bioactive soluble TNF-α, has been challenged with inhibitors to treat inflammatory diseases. Here, we report a novel anti-TNF-α strategy using a short hairpin RNA silencing TACE (shTACE) to prevent and treat colitis. The shTACE formed stable complexes with nona-arginine-based bio-cleavable disulfide bond-linked poly (arginine) (PAs-s) for enhanced gene delivery. Systemically administered shTACE/PAs-s peptoplexes efficiently decreased TNF-α levels, increased survival and alleviated pathophysiological parameters representing colitis severity. Our results demonstrate effectiveness and safety of shTACE/PAs-s peptoplexes with the capacity of overcoming acute and chronic ulcerative colitis through modulation of excessive inflammatory responses in the colon, providing a strong potential as a therapeutic agent for a broad variety of inflammatory diseases.

  7. Angiotensin I-converting enzyme (ACE) inhibitory activity and structural properties of oven- and freeze-dried protein hydrolysate from fresh water fish (Cirrhinus mrigala).

    PubMed

    Elavarasan, K; Shamasundar, B A; Badii, Faraha; Howell, Nazlin

    2016-09-01

    The angiotensin I-converting enzyme (ACE) inhibitory activity and structural properties of oven-dried (OD-FPH) and freeze-dried (FD-FPH) protein hydrolysates derived from fresh water fish (Cirrhinus mrigala) muscle, using papain, were investigated. Amino acid profiles indicated a higher proportion of hydrophobic residues in OD-FPH and hydrophilic residues in FD-FPH samples. Fourier transform infrared (FT-IR) spectra revealed random coil structure in OD-FPH and β-sheet in FD-FPH samples. The approximate molecular weight of peptides in OD-FPH and FD-FPH was in the range of 7030-339Da. The IC50 values for ACE inhibition by OD-FPH and FD-FPH samples were found to be 1.15 and 1.53mg of proteinml(-1), respectively. The ACE-inhibitory activity of OD-FPH was more stable (during sequential digestion, using pepsin and pancreatin) than that of FD-FPH sample. The study suggested that the ACE inhibitory activity of protein hydrolysate was not affected by oven-drying.

  8. Serum levels of renin, angiotensin-converting enzyme and angiotensin II in patients treated by surgical excision, propranolol and captopril for problematic proliferating infantile haemangioma.

    PubMed

    Sulzberger, L; Baillie, R; Itinteang, T; de Jong, S; Marsh, R; Leadbitter, P; Tan, S T

    2016-03-01

    The role of the renin-angiotensin system (RAS) in the biology of infantile haemangioma (IH) and its accelerated involution induced by β-blockers was first proposed in 2010. This led to the first clinical trial in 2012 using low-dose captopril, an angiotensin-converting enzyme (ACE) inhibitor, demonstrating a similar response in these tumours. This study aimed to compare serial serum levels of the components of the RAS in patients before and after surgical excision, propranolol or captopril treatment for problematic proliferating IH. Patients with problematic proliferating IH underwent measurements of serum levels of plasma renin activity (PRA), ACE and angiotensin II (ATII) before, and 1-2 and 6 months following surgical excision, propranolol or captopril treatment. This study included 27 patients undergoing surgical excision (n = 8), propranolol (n = 11) and captopril (n = 8) treatment. Treatment with either surgical excision or propranolol resulted in significant decrease in the mean levels of PRA. Surgical excision or captopril treatment led to significant decline in the mean levels of ATII. All three treatment modalities had no significant effect on the mean levels of ACE. This study demonstrates the effect of surgical excision, propranolol and captopril treatment in lowering the levels of PRA and ATII, but not ACE, supporting a mechanistic role for the RAS in the biology of IH.

  9. Impact of Angiotensin I-converting Enzyme Inhibitors and Angiotensin II Type-1 Receptor Blockers on Survival of Patients with NSCLC

    PubMed Central

    Miao, Lili; Chen, Wei; Zhou, Ling; Wan, Huanying; Gao, Beili; Feng, Yun

    2016-01-01

    It has been shown that angiotensin I-converting enzyme inhibitors (ACEIs) and angiotensin II type-1 receptor blockers (ARBs) can decrease tumor growth and tumor-associated angiogenesis and inhibit metastasis. Epidermal growth factor receptor (EGFR) mutations are found in approximately 30% of patients with advanced non-small cell lung cancer (NSCLC) in East Asia and in 10–15% of such patients in Western countries. We retrospectively identified 228 patients with histologically confirmed advanced NSCLC and 73 patients with early stage disease; 103 of these patients took antihypertensive drugs, and 112 received treatment with EGFR tyrosine kinase inhibitors (TKIs). There was a significant difference in progression-free survival after first-line therapy (PFS1) between the ACEI/ARB group and the non-ACEI/ARB group. For the patients treated with TKIs, there was a significant difference in PFS but not in overall survival (OS) between the ACEI/ARB group and the non-ACEI/ARB group. For the patients with advanced NSCLC, there was a significant difference in PFS1 between the ACEI/ARB group and the non-ACEI/ARB group. ACEI/ARB in combination with standard chemotherapy or TKIs had a positive effect on PFS1 or OS, regardless of whether the lung cancer was in the early or advanced stage. PMID:26883083

  10. Angiotensin-converting enzyme inhibition curbs tyrosine nitration of mitochondrial proteins in the renal cortex during the early stage of diabetes mellitus in rats.

    PubMed

    Ishii, Naohito; Carmines, Pamela K; Yokoba, Masanori; Imaizumi, Hiroyuki; Ichikawa, Tsuyoshi; Ikenagasa, Hideki; Kodera, Yoshio; Oh-Ishi, Masamichi; Aoki, Yoshikazu; Maeda, Tadakazu; Takenaka, Tsuneo; Katagiri, Masato

    2013-04-01

    Experiments were performed to evaluate the hypothesis that ACE (angiotensin-converting enzyme) inhibition (enalapril) suppresses 3-NT (3-nitrotyrosine) production in the renal cortex during the early stage of Type 1 DM (diabetes mellitus) in the rat. Enalapril was administered chronically for 2 weeks to subsets of STZ (streptozotocin)-induced DM and vehicle-treated sham rats. O(2)(-) (superoxide anion) and NO(x) (nitrate+nitrite) levels were measured in the media bathing renal cortical slices after 90 min incubation in vitro. SOD (superoxide dismutase) activity and 3-NT content were measured in the renal cortex homogenate. Renal cortical nitrated protein was identified by proteomic analysis. Renal cortical production of O(2)(-) and 3-NT was increased in DM rats; however, enalapril suppressed these changes. DM rats also exhibited elevated renal cortical NO(x) production and SOD activity, and these changes were magnified by enalapril treatment. 2-DE (two-dimensional gel electrophoresis)-based Western blotting revealed more than 20 spots with positive 3-NT immunoreactivity in the renal cortex of DM rats. Enalapril treatment blunted the DM-induced increase in tyrosine nitration of three proteins ACO2, GDH1 and MMSDH (aconitase 2, glutamate dehydrogenase 1 and methylmalonate-semialdehyde dehydrogenase), each of which resides in mitochondria. These data are consistent with enalapril preventing DM-induced tyrosine nitration of mitochondrial proteins by a mechanism involving suppression of oxidant production and enhancement of antioxidant capacity, including SOD activation.

  11. Effects of Angiotensin-Converting Enzyme Inhibitor Derived from Tropaeolum majus L. in Rat Preimplantation Embryos: Evidence for the Dehydroepiandrosterone and Estradiol Role

    PubMed Central

    Botelho Lourenço, Emerson Luiz; Muller, Juliane Centeno; Boareto, Ana Claudia; Lourenço, Ana Carolina; Calloi Palozi, Rhanany Alan; Lima Prando, Thiago Bruno; Dalsenter, Paulo Roberto

    2014-01-01

    Although several studies have shown the inhibitory effects of Tropaeolum majus extracts (HETM) on angiotensin-converting enzyme (ACE) activity, no studies have been carried out during the beginning of pregnancy, when humoral and hormonal imbalance may affect zygote and early embryo transport. This study investigates whether HETM can affect embryonic development when administered during the one-cell-blastocyst period. Pregnant Wistar rats received orally the HETM (3, 30, and 300 mg/kg/day) from the 1st to the 7th gestational day. Rats were killed on the 8th day of pregnancy and the following parameters were evaluated: clinical symptoms of toxicity (including organ weights), number of corpora lutea, implants per group, preimplantation losses ratio, and the serum levels of dehydroepiandrosterone (DHEA), estradiol, and progesterone. No clinical symptoms of maternal toxicity were evidenced. On the 8th day of pregnancy, the levels of DHEA and estradiol were increased and significant preimplantation losses were observed at all doses used. The present study reveals that the HETM can raise levels of DHEA and estradiol and induce difficulty in the embryo implantation in the early stages of pregnancy. The data contributes significantly to the safety aspects of using this natural product when trying to get pregnant or during pregnancy. PMID:24778700

  12. Combination of six enzymes of a marine Novosphingobium converts the stereoisomers of β-O-4 lignin model dimers into the respective monomers

    PubMed Central

    Ohta, Yukari; Nishi, Shinro; Hasegawa, Ryoichi; Hatada, Yuji

    2015-01-01

    Lignin, an aromatic polymer of phenylpropane units joined predominantly by β-O-4 linkages, is the second most abundant biomass component on Earth. Despite the continuous discharge of terrestrially produced lignin into marine environments, few studies have examined lignin degradation by marine microorganisms. Here, we screened marine isolates for β-O-4 cleavage activity and determined the genes responsible for this enzymatic activity in one positive isolate. Novosphingobium sp. strain MBES04 converted all four stereoisomers of guaiacylglycerol-β-guaiacyl ether (GGGE), a structural mimic of lignin, to guaiacylhydroxypropanone as an end metabolite in three steps involving six enzymes, including a newly identified Nu-class glutathione-S-transferase (GST). In silico searches of the strain MBES04 genome revealed that four GGGE-metabolizing GST genes were arranged in a cluster. Transcriptome analysis demonstrated that the lignin model compounds GGGE and (2-methoxyphenoxy)hydroxypropiovanillone (MPHPV) enhanced the expression of genes in involved in energy metabolism, including aromatic-monomer assimilation, and evoked defense responses typically expressed upon exposure to toxic compounds. The findings from this study provide insight into previously unidentified bacterial enzymatic systems and the physiological acclimation of microbes associated with the biological transformation of lignin-containing materials in marine environments. PMID:26477321

  13. Different reactivity to angiotensin II of peripheral and renal arteries in spontaneously hypertensive rats: effect of acute and chronic angiotensin converting enzyme inhibition

    NASA Technical Reports Server (NTRS)

    Guidi, E.; Hollenberg, N. K.

    1986-01-01

    We assessed renal blood flow and pressor responses to graded angiotensin II doses in spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) rats ingesting a diet containing 1.6% sodium basally and after acute and chronic angiotensin converting enzyme (ACE) inhibition with captopril. In the basal state the pressor response to angiotensin II was enhanced (P<0.0005) and the renal vascular response was blunted (P<0.005) in SHR compared with WKY rats. After acute captopril administration the pressor response was enhanced in both strains, and the difference between them was maintained, while the renal vascular response was enhanced in both, but more in SHR, so that the renal vascular response in the SHR became larger than in WKY (P<0.0001). Chronic captopril treatment blunted both pressor and renal responses in WKY rats, but only the pressor response in SHR. The renal vessels of SHR seem to be different from those of WKY rats in reaction to exogenous angiotensin II, and in response to both acute administration of captopril (probably acting through blockade of angiotensin II production) and chronic administration of captopril (probably acting mainly through accumulation of kinin or production of prostaglandins).

  14. C-338A polymorphism of the endothelin-converting enzyme (ECE-1) gene and the susceptibility to sporadic late-onset Alzheimer's disease and coronary artery disease.

    PubMed

    Scacchi, Renato; Gambina, Giuseppe; Broggio, Elisabetta; Ruggeri, Maria; Corbo, Rosa Maria

    2008-01-01

    The human endothelin-converting enzyme (ECE) is involved in beta-amyloid synthesis and regulation of the endothelin-1 (ET-1) vasoconstricting peptide. We investigated the distribution of the C-338A polymorphism of the ECE-1b gene in sporadic late-onset Alzheimer's disease (LOAD) and in coronary artery disease (CAD) to verify its role in the onset of these two complex diseases. Two cohorts of 458 Italian Caucasian LOAD patients and 165 CAD patients were examined for the C-338A polymorphism and compared with respective control samples (260 and 106 subjects, respectively) . The A allele was less present in LOAD patients than in controls, but an at limits statistically significant difference was achieved only in subjects aged less than 80 years, where only the AA genotypes appeared to have a protective role against the onset of the sporadic LOAD. For the overall CAD sample the pattern was similar and significant differences were observed only in subjects non carrying the apolipoprotein E (APOE) e*4 allele, where the A allele carrying genotypes had a protective role against the onset of the disease.

  15. Cost-Effectiveness of Angiotensin-Converting Enzyme Inhibitors for the Prevention of Diabetic Nephropathy in The Netherlands – A Markov Model

    PubMed Central

    Adarkwah, Charles Christian; Gandjour, Afschin; Akkerman, Maren; Evers, Silvia M.

    2011-01-01

    Objective Type 2 diabetes is the main cause of end-stage renal disease (ESRD) in Europe and the USA. Angiotensin-converting enzyme (ACE) inhibitors have a potential to slow down the progression of renal disease and therefore provide a renal-protective effect. The aim of our study was to assess the most cost-effective time to start an ACE inhibitor (or an angiotensin II receptor blocker [ARB] if coughing as a side effect occurs) in patients with newly diagnosed type 2 diabetes in The Netherlands. Methods A lifetime Markov decision model with simulated 50-year-old patients with newly diagnosed diabetes mellitus was developed using published data on costs and health outcomes and simulating the progression of renal disease. A health insurance perspective was adopted. Three strategies were compared: treating all patients at the time of diagnosing type 2 diabetes, screening for microalbuminuria, and screening for macroalbuminuria. Results In the base-case analysis, the treat-all strategy is associated with the lowest costs and highest benefit and therefore dominates screening both for macroalbuminuria and microalbuminuria. A multivariate sensitivity analysis shows that the probability of savings is 70%. Conclusions In The Netherlands for patients with type 2 diabetes prescription of an ACE inhibitor immediately after diagnosis should be considered if they do not have contraindications. An ARB should be considered for those patients developing a dry cough under ACE inhibitor therapy. The potential for cost savings would be even larger if the prevention of cardiovascular events were considered. PMID:22022539

  16. Is there an embryopathy associated with first-trimester exposure to angiotensin-converting enzyme inhibitors and angiotensin receptor antagonists? A critical review of the evidence.

    PubMed

    Polifka, Janine E

    2012-08-01

    Drugs that interfere with the renin-angiotensin system, such as angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), are widely used to manage hypertension and heart failure. Adequate functioning of the RAS is essential for normal fetal kidney development. The potential for ACEIs and ARBs to impair fetal and neonatal renal function if taken after the first trimester of pregnancy has been well documented. Although these drugs were not found to be teratogenic in animals, until recently little was known about the teratogenic effects of ACEIs and ARBs in humans when exposure was limited to the first trimester of pregnancy. New evidence from epidemiologic studies indicates that there may be an elevated teratogenic risk when these drugs are taken during the first trimester of pregnancy. However, this elevated risk does not appear to be specific to ACEIs and ARBs, but is instead related to maternal factors and diseases that typically coexist with hypertension in pregnancy, such as diabetes, advanced maternal age, and obesity. Women who become pregnant while being treated with an ACEI or ARB should be advised to avoid exposure to these drugs during the second and third trimesters of pregnancy by switching to a different class of antihypertensive drugs between weeks 8 and 10 after conception.

  17. Association between angiotensin converting enzyme gene insertion/deletion polymorphism and renal scar risk in children vesicoureteral reflex: a reappraise meta-analysis

    PubMed Central

    Ai, Jin-Wei; Zeng, Xian-Tao; Liu, Ying; Fu, Yu; Liu, Tong-Zu; Pei, Bin

    2016-01-01

    Vesicoureteral reflex(VUR) is a common disease in children. Some studies indicated that the angiotensin converting enzyme (ACE) gene insertion/deletion (I/D) polymorphism associated with the renal scar in VUR, but not all researchers agreed with it. To clarify the effect of ACE I/D polymorphism on renal scar risk in children with VUR, we performed the present meta-analysis. PubMed, CNKI, CBM, and Embase databases were searched for studies that examined the relationship between ACE I/D polymorphism and renal scar risk in children with VUR. The Stata 12.0 software was used for statistical analyses. 11 case-control studies with 1,032 VUR patients were analyzed. The results showed that the DD genotype and D allele were associated with renal scar risk in overall VUR patients, DD vs. DI + II: OR = 1.61, 95% CI = 1.04–2.49, P = 0.03; DD vs. II: OR = 1.78, 95% CI = 1.20–2.65, P < 0.01; D vs. I: OR = 1.38, 95% CI = 1.02–1.86, P = 0.04. Similar results were revealed in Turks, but not in Caucasians and Asians. Our meta-analysis indicated that the ACE DD genotype may increase the risk of renal scar in children with VUR. PMID:27506878

  18. Antioxidative and angiotensin-I-converting enzyme inhibitory potential of a Pacific Hake ( Merluccius productus ) fish protein hydrolysate subjected to simulated gastrointestinal digestion and Caco-2 cell permeation.

    PubMed

    Samaranayaka, Anusha G P; Kitts, David D; Li-Chan, Eunice C Y

    2010-02-10

    Pacific hake fish protein hydrolysate (FPH) with promising chemical assay based antioxidative capacity was studied for in vitro angiotensin-I-converting enzyme (ACE)-inhibitory potential, intestinal cell permeability characteristics, and intracellular antioxidative potential using the Caco-2 cell model system. FPH showed substrate-type inhibition of ACE with IC(50) of 161 microg of peptides/mL. HPLC analysis revealed that different peptides were responsible for antioxidative and ACE-inhibitory activity. FPH inhibited 2,2'-azobis(2-amidinopropane) dihydrochloride-induced oxidation in Caco-2 cells at noncytotoxic concentrations. In vitro simulated gastrointestinal digestion increased (P < 0.05) antioxidative capacity; ACE-inhibitory activity of FPH remained unchanged, although individual peptide fractions showed decreased or no activity after digestion. Some FPH peptides passed through Caco-2 cells: the permeates showed 2,2'-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging activity but no ACE-inhibitory activity. These results suggest the potential for application of Pacific hake FPH to reduce oxidative processes in vivo. Further studies are needed to assess prospective antihypertensive effects.

  19. Angiotensin I-Converting Enzyme inhibitory and antioxidant activities and surfactant properties of protein hydrolysates as obtained of Amaranthus hypochondriacus L. grain.

    PubMed

    Soriano-Santos, J; Escalona-Buendía, H

    2015-04-01

    Even though some research has been carried out on surfactant properties of amaranth protein hydrolysates, their bio-functionality has not been studied yet. In this work amaranth grain Alb 1 and Glob were hydrolyzed (Alb 1H, Glob H) and foams and emulsions at optimal conditions (t, E/S, pH5) were prepared in order to assess techno-functional properties such as foaming (F) and emulsifying (E) (capacity (C) and stability (S)). FC and EC were much better for Glob H than for Alb H. Angiotensin I-converting enzyme-inhibitory activity was higher for Alb 1H (roughly 50 %) than that of Glob H (roughly 30 %). Scavenging of radicals activity (DPPH· or ABTS· (+) ) of Alb 1H and Glob H, at 2 mg/mL, was similar (approx. 40 %), but lower than Alb 1 (approx. 70 %), which was the best antioxidant. The low reducing power showed that hydrolysates barely donate an electron or hydrogen. Chelating activity on Cu(2+) was lower than that exhibited by Fe(2+,) which was remarkable, approx. 80 % as long as DH% > 10 %, where hydrolysates displayed high solubility (Alb 1H = 85 %, Glob H = 70 %) because of occurrence of 1-10 kDa peptides. Amaranth foams and emulsions prepared with protein hydrolysates have a potential as a nutraceutical food.

  20. Human sperm devoid of germinal angiotensin-converting enzyme is responsible for total fertilization failure and lower fertilization rates by conventional in vitro fertilization.

    PubMed

    Li, Le-Jun; Zhang, Feng-Bin; Liu, Shu-Yuan; Tian, Yong-Hong; Le, Fang; Wang, Li-Ya; Lou, Hang-Ying; Xu, Xiang-Rong; Huang, He-Feng; Jin, Fan

    2014-06-01

    In conventional in vitro fertilization (IVF), complete failure of fertilization occurs in 5% to 15% of treatments. Although the causes may be unclear, sperm defects appear to be the major contributor. However, a convincing test is not yet available that can predict the risk of fertilization failure. In this study, we found that germinal angiotensin-converting enzyme (gACE) (also called testicular ACE) was undetectable in sperm from patients who had total fertilization failure (TFF) and lower fertilization rates (LFRs) by IVF based on Western blot and indirect immunofluorescence analyses. Additionally, almost all of the patients without gACE on sperm (23 of 25) manifested a TT genotype of the rs4316 single-nucleotide polymorphism of ACE. Overall, our results indicate that the absence of gACE expression is responsible for TFF and LFRs by IVF. The rs4316 polymorphism of ACE might be associated with infertility in those patients. We conclude that sperm lacking gACE may be recognized before commencing IVF and that the patients may be directed instead to consider intracytoplasmic sperm injection.

  1. Dynamic alteration of neprilysin and endothelin-converting enzyme in age-dependent APPswe/PS1dE9 mouse model of Alzheimer’s disease

    PubMed Central

    Zhou, Li; Liu, Jianxu; Dong, Dong; Wei, Chunsheng; Wang, Rui

    2017-01-01

    Imbalance of Aβ production and Aβ removal leads to Aβ accumulation. Aβ degrading enzyme (including neprilysin-NEP, endothelin converting enzyme-ECE) as a therapeutic strategy for lowering brain Aβ deposition has attracted increasing attention. In this study, we investigated alteration of age and region-dependent in APP/PS1 double transgenic mice (3, 6, 9, 12 months) and their age-matched wild type mice including the ability of spatial memory, Aβ deposits, the protein expression, location and activity of NEP and ECE. Our data demonstrated that, as compared with wild type mice, APP/PS1 mice displayed significant cognitive deficit at 9 month revealed by obviously longer in the latency and distance to find the platform and shorter in time spent and swimming distance in the target quadrant. Aβ40 and Aβ42 levels exhibited a significant increase with age in the cerebral cortex and hippocampus of APP/PS1 mice after 6 month, compared with their age-matched wild type mice. And Aβ42 levels were significantly higher than Aβ40 levels in the same age of APP/PS1 mice. Furthermore, NEP protein and activity displayed a marked decrease with age in the cerebral cortex and hippocampus of APP/PS1 mice older than 6 month. Slightly different from NEP, ECE protein was up-regulated with age, while ECE activity showed a significantly decrease with age in cortex and hippocampus of APP/PS1 mice older than 6 month. Double immunofluorescence staining also demonstrated that ECE and NEP highly colocalized in cytoplasmic and membrane, and ECE immunoreactivity tended to increase with age in APP/PS1 mice, especially 12 month APP/PS1 mice. Correlation analysis showed the negative correlation between enzyme (NEP or ECE) activity and Aβ levels in the cerebral cortex and hippocampus of APP/PS1 mice, which was correlated with Aβ accumulation. These results indicate NEP rather than ECE plays more important role in resisting Aβ accumulation. The compensatory upregulation of NEP and ECE could

  2. Pharmacokinetics of M100240 and MDL 100,173, a dual angiotensin-converting enzyme/neutral endopeptidase inhibitor, in healthy young and elderly volunteers.

    PubMed

    Emmons, Gary T; Argenti, Rick; Martin, Louis L; Martin, Nancy E; Jensen, Bradford K

    2004-08-01

    M100240 is an acetate thioester of MDL 100,173-a dual angiotensin-converting enzyme (ACE)/neutral endopeptidase (NEP) inhibitor-in phase II development. The pharmacokinetics of M100240 and MDL 100,173 were compared in young and elderly subjects. Pharmacokinetic data were obtained from 12 young (ages 18-45 years, 10 male, 2 female) and 12 elderly (ages 65-85 years, 7 male, 5 female) healthy subjects in a parallel-group, open-label study. Following an overnight fast, subjects received a single 25-mg oral dose of M100240. Serial plasma concentrations of M100240 and MDL 100,173 were determined using a validated liquid chromatography/tandem mass spectrometry (LC/MS/MS) method, and pharmacokinetic parameters were calculated with noncompartmental methods. Single-dose treatment with M100240 was well tolerated in both groups of subjects, with no clinically significant changes in vital signs, ECG recordings, or laboratory safety parameters. M100240 was rapidly absorbed and converted to MDL 100,173, with M100240 concentrations no longer detectable at 3 to 4 hours postdose in both groups. The pharmacokinetics of the pharmacologically active MDL 100,173 were similar for both groups. Although maximum concentrations of M100240 were generally higher in elderly versus young subjects (C(max) 0.48 ng/mL vs. 0.17 ng/mL), systemic availability of M100240 was quite low and variable with plasma, and this apparent difference in parent drug exposure is unlikely to have important clinical implications. No age-related differences in the pharmacokinetic parameters of MDL 100,173 (C(max) 8.16 vs. 9.62 ng/mL, t(max) 1.25 vs. 1.5 h, AUC((0-last)) 81.6 vs. 72.2 ng x h/mL) were observed between young and elderly subjects, respectively. In conclusion, there are no age-related differences in the pharmacokinetics of MDL 100,173 between young and elderly subjects.

  3. The angiotensin-I converting enzyme gene I/D variation contributes to end-stage renal disease risk in Chinese patients with type 2 diabetes receiving hemodialysis.

    PubMed

    Lu, Ming; Zhang, Jianzhong; Li, Ming; Ge, Xiaoxu; Dai, Xu; Zhao, Jiao; Fu, Mingzhou; Wang, Tao; Fang, Xiyao; Li, Can; Zhang, Rong; Zhao, Weijing; Zheng, Taishan; Wang, Feng; Yu, Ming; Lei, Tao; Wang, Niansong; Bao, Yuqian; Liu, Limei; Liu, Yanjun; Jia, Weiping

    2016-11-01

    Whether the DD genotype of the angiotensin-I converting enzyme (ACE) I/D variation contributes to end-stage renal disease (ESRD) risk in type 2 diabetes mellitus (T2DM) remains controversial. Differences in study design, case and control definition, sample size and ethnicity may contribute to the discrepancies reported in association studies. We performed a case-control study to evaluate the association of the ACE I/D variation with ESRD risk in Chinese patients with T2DM receiving hemodialysis and analyzed the genotype-phenotype interaction. Unrelated Chinese patients (n = 432) were classified into the non-diabetic nephropathy (DN) control group (n = 222, duration of diabetes >10 years, no signs of renal involvement) and the DN-ESRD group (n = 210; ESRD due to T2DM, receiving hemodialysis). Polymerase chain reaction was used to genotype ACE I/D for all 432 subjects. The frequencies of the ID + DD genotypes were higher in the DN-ESRD group than non-DN control group (65.2 vs. 50.9 %; adjusted OR 1.98 (95 % CI, 1.31-3.00; P = 0.001). In the DN-ESRD group, the DD genotypic subgroup had significantly elevated HbA1c and diastolic blood pressure (DBP) compared to the II subgroup (both P < 0.05). The DD genotype of the ACE I/D variation may be associated with more elevated blood pressure and HbA1c, and therefore may predict the development, progression and severity of DN-ESRD in Chinese patients with T2DM undergoing hemodialysis.

  4. Inhibition of angiotensin-1-converting enzyme activity by two varieties of ginger (Zingiber officinale) in rats fed a high cholesterol diet.

    PubMed

    Akinyemi, Ayodele Jacob; Ademiluyi, Adedayo Oluwaseun; Oboh, Ganiyu

    2014-03-01

    Angiotensin-1-converting enzyme (ACE) inhibitors are widely used in the treatment of cardiovascular diseases. This study sought to investigate the inhibitory effect of two varieties of ginger (Zingiber officinale) commonly consumed in Nigeria on ACE activity in rats fed a high cholesterol diet. The inhibition of ACE activity of two varieties of ginger (Z. officinale) was investigated in a high cholesterol (2%) diet fed to rats for 3 days. Feeding high cholesterol diets to rats caused a significant (P<.05) increase in the ACE activity. However, there was a significant (P<.05) inhibition of ACE activity as a result of supplementation with the ginger varieties. Rats that were fed 4% white ginger had the greatest inhibitory effect as compared with a control diet. Furthermore, there was a significant (P<.05) increase in the plasma lipid profile with a concomitant increase in malondialdehyde (MDA) content in rat liver and heart tissues. However, supplementing the diet with red and white ginger (either 2% or 4%) caused a significant (P<.05) decrease in the plasma total cholesterol, triglyceride, very low density lipoprotein-cholesterol, and low-density lipoprotein-cholesterol levels, and in MDA content in the tissues. Conversely, supplementation caused a significant (P<.05) increase in plasma high-density lipoprotein-cholesterol level when compared with the control diet. Nevertheless, rats fed 4% red ginger had the greatest reduction as compared with control diet. In conclusion, both ginger varieties exhibited anti-hypercholesterolemic properties in a high cholesterol diet fed to rats. This activity of the gingers may be attributed to its ACE inhibitory activity. However, white ginger inhibited ACE better in a high cholesterol diet fed to rats than red ginger. Therefore, both gingers could serve as good functional foods/nutraceuticals in the management/treatment of hypertension and other cardiovascular diseases.

  5. Impact of the additive effect of angiotensin-converting enzyme inhibitors and /or statins with antiplatelet medication on mortality after acute ischaemic stroke.

    PubMed

    Hassan, Yahaya; Al-Jabi, Samah W; Aziz, Noorizan Abd; Looi, Irene; Zyoud, Sa'ed H

    2012-04-01

    There has been recent interest in combining antiplatelets, angiotensin-converting enzyme inhibitors (ACEIs) and statins in primary and secondary ischaemic stroke prevention. This observational study was performed to evaluate the impact of adding ACEIs and/or statins to antiplatelets on post-stroke in-hospital mortality. Ischaemic stroke patients attending a hospital in Malaysia over an 18-month period were evaluated. Patients were categorized according to their vital status at discharge. Data included demographic information, risk factors, clinical characteristics and previous medications with particular attention on antiplatelets, ACEIs and statins. In-hospital mortality was compared among patients who were not taking antiplatelets, ACEIs or statins before stroke onset versus those who were taking antiplatelets alone or in combination with either ACEIs, statins or both. Data analysis was performed using SPSS version 15. Overall, 637 patients met the study inclusion criteria. After controlling for the effects of confounders, adding ACEIs or statins to antiplatelets significantly decreased the incidence of death after stroke attack by 68% (p = 0.036) and 81% (p = 0.010), respectively, compared to patients on antiplatelets alone or none of these medications. Additionally, the addition of both ACEIs and statins to antiplatelet medication resulted in the highest reduction (by 94%) of the occurrence of death after stroke attack (p < 0.001). Our results suggest that adding ACEIs and/or statins to antiplatelets for patients at risk of developing stroke, either as a primary or as a secondary preventive regimen, was associated with a significant reduction in the incidence of mortality after ischaemic stroke than antiplatelets alone. These results might help reduce the rate of ischaemic stroke morbidity and mortality by enhancing the application of specific therapeutic and management strategies for patients at a high risk of acute stroke.

  6. Pharmacogenetic effects of angiotensin-converting enzyme inhibitors over age-related urea and creatinine variations in patients with dementia due to Alzheimer disease

    PubMed Central

    Berretta, Juliana Marília; Suchi Chen, Elizabeth; Cardoso Smith, Marilia; Ferreira Bertolucci, Paulo Henrique

    2016-01-01

    Background: Renal function declines according to age and vascular risk factors, whereas few data are available regarding genetically-mediated effects of anti-hypertensives over renal function. Objective: To estimate urea and creatinine variations in dementia due to Alzheimer disease (AD) by way of a pharmacogenetic analysis of the anti-hypertensive effects of angiotensin-converting enzyme inhibitors (ACEis). Methods: Consecutive outpatients older than 60 years-old with AD and no history of kidney transplant or dialytic therapy were recruited for prospective correlations regarding variations in fasting blood levels of urea and creatinine in one year, considering ACE genotypes of rs1800764 and rs4291 and their respective haplotypes, and treatment with ACEis along with blood pressure variations. Results: For 190 patients, 152 had arterial hypertension, and 122 used ACEis. Minor allele frequencies were 0.492 for rs1800764-C and 0.337 for rs4291-T, both in Hardy-Weinberg equilibrium. There were no overall significant yearly variations in levels of urea and creatinine, but their concurrent variations were positively correlated (ρ <0.0001). Each A allele of rs4291 led to an yearly urea increase of 3,074 mg/dL, and an yearly creatinine increase of 0.044 mg/dL, while the use of ACEis was protective regarding creatinine variations. The use of ACEis was also protective for carriers of rs1800764-CT/rs4291-AA, while carriers of rs1800764-CT/rs4291-AT had steeper reductions in creatinine levels, particularly when they were treated with ACEis. Conclusions: Effects of ACEis over creatinine variations are genetically mediated and independent of blood pressure variations in older people with AD. PMID:27546928

  7. Association of Angiotensin Converting Enzyme Insertion-Deletion Polymorphism with Hypertension in Emiratis with Type 2 Diabetes Mellitus and Its Interaction with Obesity Status

    PubMed Central

    Alsafar, Habiba; Hassoun, Ahmed; Almazrouei, Shaikha; Kamal, Wala; Almaini, Mustafa; Odama, Unini; Rais, Naushad

    2015-01-01

    The association of Angiotensin Converting Enzyme (ACE) insertion-deletion (I/D) polymorphism with Type 2 Diabetes Mellitus (T2DM) and hypertension has been extensively studied throughout various ethnic populations but largely with inconsistent findings. We investigated these associations in Emirati population and their interaction with obesity status. Saliva samples were collected from a total of 564 Emiratis (277 T2DM and 297 healthy). DNA was extracted and the samples were genotyped for ACE I/D polymorphism by a PCR based method followed by gel electrophoresis. Upon evaluation of the ACE I/D polymorphism amongst all T2DM, hypertensive patients, and respective controls regardless of obesity status, ACE DD genotype was not found to be associated with either T2DM [odds ratio (OR) = 1.34, p = 0.086] or hypertension [odd ratio (OR) = 1.02, p = 0.93]. When the genetic variants amongst the nonobese and obese population were analyzed separately, the risk genotype ACE DD conferred significantly increased risk of hypertension in nonobese population [odds ratio (OR) = 1.80, p = 0.02] but was found to be protective against the hypertension in the obese group ((OR) = 0.54, p = 0.01). However, there was no effect of obesity status on the association of ACE genotypes with T2DM. The risk of hypertension associated with ACE DD is modulated by obesity status and hence future genetic association studies should take obesity into account for the interpretation of data. We also confirmed that ACE I/D polymorphism is not associated with T2DM risk in Emirati population. PMID:26491214

  8. Update on the Angiotensin Converting Enzyme 2-Angiotensin (1–7)-Mas Receptor Axis: Fetal Programing, Sex Differences, and Intracellular Pathways

    PubMed Central

    Chappell, Mark C.; Marshall, Allyson C.; Alzayadneh, Ebaa M.; Shaltout, Hossam A.; Diz, Debra I.

    2013-01-01

    The renin-angiotensin-system (RAS) constitutes an important hormonal system in the physiological regulation of blood pressure. Indeed, dysregulation of the RAS may lead to the development of cardiovascular pathologies including kidney injury. Moreover, the blockade of this system by the inhibition of angiotensin converting enzyme (ACE) or antagonism of the angiotensin type 1 receptor (AT1R) constitutes an effective therapeutic regimen. It is now apparent with the identification of multiple components of the RAS that the system is comprised of different angiotensin peptides with diverse biological actions mediated by distinct receptor subtypes. The classic RAS can be defined as the ACE-Ang II-AT1R axis that promotes vasoconstriction, sodium retention, and other mechanisms to maintain blood pressure, as well as increased oxidative stress, fibrosis, cellular growth, and inflammation in pathological conditions. In contrast, the non-classical RAS composed of the ACE2-Ang-(1–7)-Mas receptor axis generally opposes the actions of a stimulated Ang II-AT1R axis through an increase in nitric oxide and prostaglandins and mediates vasodilation, natriuresis, diuresis, and oxidative stress. Thus, a reduced tone of the Ang-(1–7) system may contribute to these pathologies as well. Moreover, the non-classical RAS components may contribute to the effects of therapeutic blockade of the classical system to reduce blood pressure and attenuate various indices of renal injury. The review considers recent studies on the ACE2-Ang-(1–7)-Mas receptor axis regarding the precursor for Ang-(1–7), the intracellular expression and sex differences of this system, as well as an emerging role of the Ang1-(1–7) pathway in fetal programing events and cardiovascular dysfunction. PMID:24409169

  9. The transcription factor HNF1α induces expression of angiotensin-converting enzyme 2 (ACE2) in pancreatic islets from evolutionarily conserved promoter motifs.

    PubMed

    Pedersen, Kim Brint; Chhabra, Kavaljit H; Nguyen, Van K; Xia, Huijing; Lazartigues, Eric

    2013-11-01

    Pancreatic angiotensin-converting enzyme 2 (ACE2) has previously been shown to be critical for maintaining glycemia and β-cell function. Efforts to maintain or increase ACE2 expression in pancreatic β-cells might therefore have therapeutic potential for treating diabetes. In our study, we investigated the transcriptional role of hepatocyte nuclear factor 1α (HNF1α) and hepatocyte nuclear factor 1β (HNF1β) in induction of ACE2 expression in insulin-secreting cells. A deficient allele of HNF1α or HNF1β causes maturity-onset diabetes of the young (MODY) types 3 and 5, respectively, in humans. We found that ACE2 is primarily transcribed from the proximal part of the ACE2 promoter in the pancreas. In the proximal part of the human ACE2 promoter, we further identified three functional HNF1 binding sites, as they have binding affinity for HNF1α and HNF1β and are required for induction of promoter activity by HNF1β in insulinoma cells. These three sites are well-conserved among mammalian species. Both HNF1α and HNF1β induce expression of ACE2 mRNA and lead to elevated levels of ACE2 protein and ACE2 enzymatic activity in insulinoma cells. Furthermore, HNF1α dose-dependently increases ACE2 expression in primary pancreatic islet cells. We conclude that HNF1α can induce the expression of ACE2 in pancreatic islet cells via evolutionarily conserved HNF1 binding sites in the ACE2 promoter. Potential therapeutics aimed at counteracting functional HNF1α depletion in diabetes and MODY3 will thus have ACE2 induction in pancreatic islets as a likely beneficial effect.

  10. Multi-spectroscopic and molecular modeling studies of interaction between two different angiotensin I converting enzyme inhibitory peptides from gluten hydrolysate and human serum albumin.

    PubMed

    Assaran Darban, Reza; Shareghi, Behzad; Asoodeh, Ahmad; Chamani, Jamshidkhan

    2016-12-26

    The present study was carried out to characterize Angiotensin-converting enzyme (ACE) inhibitory peptides which are released from the trypsin hydrolysate of wheat gluten protein. The binding of two inhibitory peptide (P4 and P6) to human serum albumin (HSA) under physiological conditions has been investigated by multi-spectroscopic in combination with molecular modeling techniques. Time-resolved and quenching fluorescence spectroscopies results revealed that the quenching of HSA fluorescence by P4 and P6 in the binary and ternary systems caused HSA-peptides complexes formation. The results indicated that both peptides quenched the fluorescence intensity of