Cloning, Sequencing, and cDNA-Directed Expression of the Rat Renal CYP4A2: Arachidonic Acid ω-Hydroxylation and 11,12-Epoxidation by CYP4A2 Protein

Wang, Mong Heng; Stec, David E.; Balazy, Michael; Mastyugin, Vladimir; Yang, Chung S.; Roman, Richard J.; Schwartzman, Michal Laniado

doi:10.1006/abbi.1996.0554

Cited by 68 publications

(40 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Interestingly, these two human P450s exhibited the same highly specific pattern of distribution within the nephron and were not expressed in cells comprising the glomeruli, loops of Henle, or collecting tubules. Thus, the proximal tubular pars convoluta and pars recta segments represents the principal site for 20-HETE formation in the human kidney, an observation similar to that made in experimental animals (18,19,26,29). This pattern of CYP4F2 and CYP4A11 distribution in human kidney has, in all likelihood, important implications with regard to effects of AA-derived eicosanoids on integrated renal function.…”

Section: -Hete Formation By Human Renal P450 Enzymessupporting

confidence: 67%

“…Furthermore, since the proximal tubule is where most electrolyte and water reabsorption occurs (1), the capacity of 20-HETE to potently inhibit Na ϩ /K ϩ -ATPase activity in this region of the nephron probably contributes to its known natriuretic and diuretic effects (4,62,74). In rats, CYP4A expression and 20-HETE formation have also been noted in renal microvessels (19,29,75), another proposed site where this eicosanoid influences vascular tone, autoregulation of renal blood flow, and/or tubuloglomerular feedback (9,10). However, the absence of CYP4 enzymes from the human renal vasculature suggests that synthesis of 20-HETE exclusively within the proximal tubules is sufficient for this compound to elicit its potent effects on kidney function.…”

Section: -Hete Formation By Human Renal P450 Enzymesmentioning

confidence: 99%

“…5,6-EET and 11,12-EET) in the regulation of renal function has been proposed (3,24,25). With regard to 20-HETE, three different CYP4A P450s capable of AA 20-hydroxylation, namely CYP4A1, CYP4A2, and CYP4A3, are expressed in rat kidney (19, 26 -28), although more recent studies have attributed the bulk of renal 20-HETE formation in this species to CYP4A2 (18,19,29) The predominant catalyst of AA -hydroxylation in rabbit kidney has been identified as CYP4A6 and/or CYP4A7 (30 -32). In contrast, there have been few studies characterizing P450-mediated AA oxygenation in the human kidney (33,34), and the renal P450 enzymes underlying formation of 20-HETE or any other AA metabolite have yet to be identified in humans.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Formation of 20-Hydroxyeicosatetraenoic Acid, a Vasoactive and Natriuretic Eicosanoid, in Human Kidney

Lasker¹,

Chen²,

Wolf³

et al. 2000

Journal of Biological Chemistry

283

265

View full text Add to dashboard Cite

20-Hydroxyeicosatetraenoic acid (20-HETE), an -hydroxylated arachidonic acid (AA) metabolite, elicits specific effects on kidney vascular and tubular function that, in turn, influence blood pressure control. The human kidney's capacity to convert AA to 20-HETE is unclear, however, as is the underlying P450 catalyst. Microsomes from human kidney cortex were found to convert AA to a single major product, namely 20-HETE, but failed to catalyze AA epoxygenation and midchain hydroxylation. Despite the monophasic nature of renal AA -hydroxylation kinetics, immunochemical studies revealed participation of two P450s, CYP4F2 and CYP4A11, since antibodies to these enzymes inhibited 20-HETE formation by 65.9 ؎ 17 and 32.5 ؎ 14%, respectively. Western blotting confirmed abundant expression of these CYP4 proteins in human kidney and revealed that other AA-oxidizing P450s, including CYP2C8, CYP2C9, and CYP2E1, were not expressed. Immunocytochemistry showed CYP4F2 and CYP4A11 expression in only the S2 and S3 segments of proximal tubules in cortex and outer medulla. Our results demonstrate that CYP4F2 and CYP4A11 underlie conversion of AA to 20-HETE, a natriuretic and vasoactive eicosanoid, in human kidney. Considering their proximal tubular localization, these P450 enzymes may partake in pivotal renal functions, including the regulation of salt and water balance, and arterial blood pressure itself.

show abstract

Section: -Hete Formation By Human Renal P450 Enzymessupporting

confidence: 67%

Section: -Hete Formation By Human Renal P450 Enzymesmentioning

confidence: 99%

mentioning

confidence: 99%

See 1 more Smart Citation

Formation of 20-Hydroxyeicosatetraenoic Acid, a Vasoactive and Natriuretic Eicosanoid, in Human Kidney

Lasker¹,

Chen²,

Wolf³

et al. 2000

Journal of Biological Chemistry

283

265

View full text Add to dashboard Cite

show abstract

“…However, it is difficult to study the interaction between NO and CYP4A isoforms in renal tissues because renal tissues contain numerous CYP enzymes other than CYP4A isoforms. Baculovirus-expressed CYP4A isoforms provide a unique tool to study the interaction between NO and individual CYP4A isoforms in vitro because there is a negligible level of CYP content in Sf9 insect cells (39). Our results indicated that NO binds to the heme moiety of CYP4A1 and CYP4A3 with different affinities.…”

Section: Discussionmentioning

confidence: 82%

Regulation of renal CYP4A expression and 20-HETE synthesis by nitric oxide in pregnant rats

Wang

Chang

et al. 2003

American Journal of Physiology-Renal Physiology

Self Cite

View full text Add to dashboard Cite

Hydroxyeicosatetraenoic acid (20-HETE), which promotes renal vasoconstriction, is formed in the rat kidney primarily by cytochrome P-450 (CYP) 4A isoforms (4A1, 4A2, 4A3, 4A8). Nitric oxide (NO) has been shown to bind to the heme moiety of the CYP4A2 protein and to inhibit 20-HETE synthesis in renal arterioles of male rats. However, it is not known whether NO interacts with and affects the activity of CYP4A1 and CYP4A3, the major renal CYP4A isoforms in female rats. Incubation of recombinant CYP4A1 and 4A3 proteins with sodium nitroprusside (SNP) shifted the absorbance at 440 nm, indicating the formation of a ferric-nitrosyl-CYP4A complex. The absorbance for CYP4A3 was about twofold higher than that of CYP4A1. Incubation of SNP or peroxynitrite (PN; 0.01-1 mM) with CYP4A recombinant membranes caused a concentration-dependent inhibition of 20-HETE synthesis, with both chemicals having a greater inhibitory effect on CYP4A3-catalyzed activity. Moreover, incubation of CYP4A1 and 4A3 proteins with PN (1 mM) resulted in nitration of tyrosine residues in both proteins. In addition, PN and SNP inhibited 20-HETE synthesis in renal microvessels from female rats by 65 and 59%, respectively. We previously showed that microvessel CYP4A1/CYP4A3 expression and 20-HETE synthesis are decreased in late pregnancy. Therefore, we investigated whether such a decrease is dependent on NO, the synthesis of which has been shown to increase in late pregnancy. Administration of N G -nitro-L-arginine methyl ester (L-NAME) to pregnant rats for 6 days (days 15-20 of pregnancy) caused a significant increase in systolic blood pressure, which was prevented by concurrent treatment with the CYP4A inhibitor 1-aminobenzotriazole (ABT). Urinary NO2/NO3 excretion decreased by 40 and 52% in L-NAMEand L-NAME ϩ ABT-treated groups, respectively. Interestingly, renal microvessel 20-HETE synthesis showed a marked increase following L-NAME treatment, and this increase was diminished with coadministration of ABT. These results demonstrate that NO interacts with CYP4A proteins in a distinct manner and it interferes with renal microvessel 20-HETE synthesis, which may play an important role in the regulation of blood pressure and renal function during pregnancy.cytochrome P-450 4A; N G -nitro-L-arginine methyl ester 20-HYDROXYEICOSATETRAENOIC acid (20-HETE), the -hydroxylation product of arachidonic acid (AA), is a principal eicosanoid in vascular and tubular structures of the rat kidney whose synthesis is catalyzed primarily by isoforms of the cytochrome P-450 (CYP) 4A gene family (34). In the rat, four CYP4A isoforms, CYP4A1, 4A2, 4A3, and 4A8, have been identified. The renal expression of CYP4A isoforms has been shown to be tissue specific as well as age and sex dependent (9,12,13,19,20). For example, Sundseth and Waxman (37) demonstrated that hepatic and renal CYP4A1 and 4A3 expressions are similar in male and female rats, whereas CYP4A2 expression is undetectable in female rats. Castration of male rats decreased the levels of CYP4A2, and treatment of cast...

show abstract

“…It has been shown that CYP4A2 and CYP4A3 can produce 20-HETE as well as 11,12-EET (precursor of 11,12-DHET). 27,32 Thus, it is possible that DDMS also inhibits CYP4A2 and thus 11,12-EET (or 11,12-DHET) production. The extent of the contribution of 14,15-DHET in cardioprotection, if any, remains unknown.…”

Section: Discussionmentioning

confidence: 99%

Inhibition of Cytochrome P450ω-Hydroxylase

Nithipatikom

Gross

Endsley

et al. 2004

Circulation Research

107

View full text Add to dashboard Cite

Abstract-Cytochrome P450s (CYP) and their arachidonic acid (AA) metabolites have important roles in regulating vascular tone, but their function and specific pathways involved in modulating myocardial ischemia-reperfusion injury have not been clearly established. Thus, we characterized the effects of several selective CYP-hydroxylase inhibitors and a CYP-hydroxylase metabolite of AA, 20-hydroxyeicosatetraenoic acid (20-HETE), on the extent of ischemiareperfusion injury in canine hearts. During 60 minutes of ischemia and particularly after 3 hours of reperfusion, 20-HETE was produced at high concentrations. A nonspecific CYP inhibitor, miconazole, and 2 specific CYPhydroxylase inhibitors, 17-octadecanoic acid (17-ODYA) and N-methylsulfonyl-12,12-dibromododec-11-enamide (DDMS), markedly inhibited 20-HETE production during ischemia-reperfusion and produced a profound reduction in myocardial infarct size (expressed as a percent of the area at risk Key Words: arachidonic acid metabolites Ⅲ cytochrome p450 Ⅲ 20-HETE Ⅲ ischemia Ⅲ reperfusion I t has long been recognized that ischemia-reperfusion of the canine heart results in an accumulation of unesterified arachidonic acid (AA). 1,2 AA can be metabolized by cytochrome P450 (CYP) expoxygenases to 4 regioisomeric epoxyeicosatrienoic acids (5,6-EET, 8,9-EET, 11,12-EET, and 14,15-EET) and by CYP-hydroxylases to 20-hydroxyeicosatetraenoic acid (20-HETE). 3-6 Subsequently, EETs can be further metabolized to their corresponding dihydroxyeicosatrienoic acids (DHETs) by epoxide hydrolases. 7,8 Although EETs relax many blood vessels, including coronary, cerebral, renal, and pial arteries, and hyperpolarize vascular smooth muscle cells possibly by activation of calcium activated potassium (Kca) channels, 9 DHETs produce relaxation only in some vessels. 10,11 However, 20-HETE is a potent vasoconstrictor 12 that activates L-type Ca 2ϩ channels leading to vasoconstriction of renal afferent arterioles. 13,14 As noted, roles of these eicosanoids in the regulation of peripheral vascular tone have been extensively investigated. However, their functions during ischemia and after reperfusion in the heart and coronary circulation, as well as mechanisms responsible for their vascular and myocardial properties are not well-understood. It is known that CYP metabolites are involved in AA-induced relaxation of canine coronary arteries. 15 Both EETs and DHETs have been shown to be potent vasodilators in the canine coronary microcirculation. 16 The production of EETs and DHETs was increased in stenosed canine coronary arteries. 17 Recently, nonspecific CYP inhibitors such as chloramphenicol, cimetidine, and sulfaphenazole have been reported to reduce ischemia-reperfusion injury, as measured by recovery of contractile function and reduction of infarct size, in rat and rabbit hearts. 18 However, because the drugs used to inhibit CYP were not selective inhibitors, it was difficult to determine the precise pathway or metabolite responsible.Previously, we found that high plasma concentrations of CYP ...

show abstract

Cloning, Sequencing, and cDNA-Directed Expression of the Rat Renal CYP4A2: Arachidonic Acid ω-Hydroxylation and 11,12-Epoxidation by CYP4A2 Protein

Cited by 68 publications

References 0 publications

Formation of 20-Hydroxyeicosatetraenoic Acid, a Vasoactive and Natriuretic Eicosanoid, in Human Kidney

Formation of 20-Hydroxyeicosatetraenoic Acid, a Vasoactive and Natriuretic Eicosanoid, in Human Kidney

Regulation of renal CYP4A expression and 20-HETE synthesis by nitric oxide in pregnant rats

Inhibition of Cytochrome P450ω-Hydroxylase

Contact Info

Product

Resources

About