Oxidation-induced increase in activity of angiotensin converting enzyme in the rat kidney

Ikemoto, Fumihiko; Song, Gyeong-Bu; Tominaga, Munechika; Yamamoto, Kenjiro

doi:10.1016/s0006-291x(88)81332-9

Cited by 15 publications

(14 citation statements)

References 7 publications

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“…Using the same synthetic substrate to assess ACE activity (Hip‐His‐Leu), Tominaga et al 28 also observed that the activity of ACE in crude extracts of different tissues was increased by oxidation. When O 2 , for example, was added to homogenates, Tominaga et al reported a large increase in ACE activity to about twice the original activity 29 . In our hands, however, bubbling of a renal tissue homogenate with O 2 did not affect ACE activity (data not shown).…”

Section: Discussioncontrasting

confidence: 55%

Inhibitory Effect Of Reactive Oxygen Species On Angiotensin I‐Converting Enzyme (Kininase II)

Michel

Grima

et al. 2001

Clin Exp Pharma Physio

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1. Somatic angiotensin I-converting enzyme (ACE) is a protein that contains two similar domains (N- and C-terminal), each possessing an active site. We have examined the effects of a generator of hydroxyl radicals (g*OH: 2,2'-azo-bis(2-amidinopropane)) and hydrogen peroxide (H2O2) on ACE using an in vitro approach. 2. The generator of hydroxyl radicals inactivated ACE in a time (2-6 h)- and concentration (0.3-3 mmol/L)-dependent manner at 37 degrees C. When ACE was coincubated for 4 h with g*OH (3 mmol/L), its activity decreased by 70%. Addition of dimethylthiourea or mannitol + methionine, two *OH scavengers, resulted in a significant protection of ACE activity. Mercaptoethanol and dithiotreitol, two thiol-reducing agents, also efficiently protected ACE activity. 3. The hydrolysis of two natural and domain-specific substrates was explored. The hydrolysis of angiotensin I, preferentially cleaved by the C-domain, was significantly inhibited (57-58%) after 4 h exposure to g*OH (0.3-1 mmol/L). Under the same conditions of exposure, the hydrolysis of N-acetyl-Ser-Asp-Lys-Pro, a specific substrate for the N-domain, was only slightly inhibited by 1 mmol/L g*OH. 4. Hydrogen peroxide, another source of *OH, was used. After exposure to H2O2 (3 mmol/L; 4 h), an 89% decrease in ACE activity was observed. Pretreatment with the iron chelator deferoxamine (1 mmol/L) attenuated H2O2-mediated ACE inactivation, demonstrating that the effect of H2O2 was partly due to its conversion into *OH (Fenton reaction). 5. In summary, our findings demonstrate that g*OH and H2O2 inhibit ACE activity and suggest a preferential action of g*OH on the C-domain of the enzyme.

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Section: Discussioncontrasting

confidence: 55%

Inhibitory Effect Of Reactive Oxygen Species On Angiotensin I‐Converting Enzyme (Kininase II)

Michel

Grima

et al. 2001

Clin Exp Pharma Physio

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“…Fukami et al [146] showed that AGEs acting via RAGEs increase intracellular ROS stimulating an increase AII. Oxidative stress increased the activity of ACE in rat kidney likely via oxidation of SH groups [147]. Besides ACE, an alternate AII-generating tissue enzyme, chymase, appears to be responsible for up to 70% of increased AII production in response to AGEs [148].…”

Section: Ages and The Renin Angiotensin Systemmentioning

confidence: 98%

Role of Advanced Glycation End Products in Hypertension and Atherosclerosis: Therapeutic Implications

Vasdev

Gill

Singal

2007

Cell Biochem Biophys

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The vascular diseases, hypertension and atherosclerosis, affect millions of individuals worldwide, and account for a large number of deaths globally. A better understanding of the mechanism of these conditions will lead to more specific and effective therapies. Hypertension and atherosclerosis are both characterized by insulin resistance, and we suggest that this plays a major role in their etiology. The cause of insulin resistance is not known, but may be a result of a combination of genetic and lifestyle factors. In insulin resistance, alterations in glucose and lipid metabolism lead to the production of excess aldehydes including glyoxal and methylglyoxal. These aldehydes react non-enzymatically with free amino and sulfhydryl groups of amino acids of proteins to form stable conjugates called advanced glycation end products (AGEs). AGEs act directly, as well as via receptors to alter the function of many intra- and extracellular proteins including antioxidant and metabolic enzymes, calcium channels, lipoproteins, and transcriptional and structural proteins. This results in endothelial dysfunction, inflammation and oxidative stress. All these changes are characteristic of hypertension and atherosclerosis. Human and animal studies have demonstrated that increased AGEs are also associated with these conditions. A pathological role for AGEs is substantiated by studies showing that therapies that attenuate insulin resistance and/or lower AGEs, are effective in decreasing oxidative stress, lowering blood pressure, and attenuating atherosclerotic vascular changes. These interventions include lipoic acid and other antioxidants, AGE breakers or soluble receptors of AGEs, and aldehyde-binding agents like cysteine. Such therapies may offer alternative specific means to treat hypertension and atherosclerosis. An adjunct therapy may be to implement lifestyle changes such as weight reduction, regular exercise, smoking cessation, and increasing dietary intake of fruits and vegetables that also decrease insulin resistance as well as oxidative stress.

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“…Urinary excretion of kallikrein and kinin availability are altered in several forms of human and animal models of hypertension (30,31), A decrease in ACE in CA-treated rats can induce the formation of kinins by preventing ACE induced-inhibition of kininase activity (6). Under oxidative stress, there is an increase ACE activity (32), and CA may prevent the oxidation of ACE and reduce its activity. This could contribute to increased availability of kinins, eventually activating the kinin B2 receptor and enhancing the NO • and PG formation.…”

mentioning

confidence: 99%

Increase in Nitric Oxide and Reductions in Blood Pressure, Protein Kinase C β II and Oxidative Stress by L-Carnitine: A Study in the Fructose-Fed Hypertensive Rat

Rajasekar

Palanisamy

Chandrasekaran

2007

Clinical and Experimental Hypertension

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Recently we showed that the administration of intraperitoneal L-carnitine (CA) has insulin-sensitizing effects in the high fructose-fed Wistar rat, a widely used model of metabolic syndrome. The present study was conducted to examine the regulatory effects of CA on blood pressure (BP) and related pressor mechanisms. Fructose-fed rats (FFR) showed elevated BP, cardiac hypertrophy, glucose intolerance, and increases in plasma glucose, insulin, free fatty acids (FFA), and angiotensin-converting enzyme (ACE) activity. They also showed increased protein kinase C betaII (PKC betaII) expression and oxidative stress in cardiac tissue. In plasma, decreased kallikrein enzyme activity and nitric oxide metabolites were observed, compared to control. Simultaneous treatment with CA (300 mg/Kg) mitigated these alterations. PKC betaII expression was similar to that of control; the rats displayed normal BP and ACE activity, enhanced antioxidant protection, and close to normal values of metabolic parameters. The BP-lowering effect of CA was abolished when CA-treated rats were administered L-nitroarginyl methyl ester (L-NAME 6g/Kg). These observations suggest that the BP-lowering action of CA in this model could be attributed to multiple and interrelated mechanisms, such as an increase in NO and kinin availability, reduction in PKC action, and antioxidant protection.

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Oxidation-induced increase in activity of angiotensin converting enzyme in the rat kidney

Cited by 15 publications

References 7 publications

Inhibitory Effect Of Reactive Oxygen Species On Angiotensin I‐Converting Enzyme (Kininase II)

Inhibitory Effect Of Reactive Oxygen Species On Angiotensin I‐Converting Enzyme (Kininase II)

Role of Advanced Glycation End Products in Hypertension and Atherosclerosis: Therapeutic Implications

Increase in Nitric Oxide and Reductions in Blood Pressure, Protein Kinase C β II and Oxidative Stress by L-Carnitine: A Study in the Fructose-Fed Hypertensive Rat

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