A Polymorphism Regulates CYP4A11 Transcriptional Activity and Is Associated With Hypertension in a Japanese Population

Effects of acidic non-steroidal anti-inflammatory drugs on human cytochrome P450 4A11 activity: Roles of carboxylic acid and a sulfur atom in potent inhibition by sulindac sulfide

Cytochrome P450 4A11 (CYP4A11) has many endogenous and exogenous compounds containing a carboxyl group in their structure as substrates. If drugs with this characteristic potently attenuate the catalytic function of CYP4A11, drug-drug interactions may occur. Acidic non-steroidal anti-inflammatory drugs (NSAIDs) possess a carboxylic acid in their structure. However, it remains unclear whether these drugs inhibit CYP4A11 activity. The present study examined the inhibitory effects of acidic NSAIDs on CYP4A11 activity using human liver microsomes (HLMs) and recombinant CYP4A11. Sulindac sulfide, ibuprofen, and flurbiprofen effectively decreased the luciferin-4A O-demethylase activity of HLMs and recombinant CYP4A11 (inhibition rates of 30-96% at an inhibitor concentration of 100 μM), while salicylic acid, aspirin, diclofenac, mefenamic acid, indomethacin, etodolac, ketoprofen, loxoprofen, S-naproxen, pranoprofen, zaltoprofen, and oxaprozin exhibited weaker inhibitory activity (inhibition rates up to 23%). Among the drugs tested, sulindac sulfide was the most potent inhibitor of CYP4A11 activity. A kinetic analysis of the inhibition of CYP4A11 by sulindac sulfide revealed mixed-type inhibition for HLMs (Ki = 3.38 μM) and recombinant CYP4A11 (Ki = 4.19 μM). Sulindac sulfide is a pharmacologically active metabolite of sulindac (sulfoxide form), which is also oxidized to sulindac sulfone. To elucidate the role of a sulfur atom of sulindac sulfide in the inhibition of CYP4A11, the inhibitory effects of sulindac sulfide and its oxidized forms on CYP4A11 activity were examined. The potency of inhibition against HLMs was greater in the order of sulindac sulfide, sulindac, and sulindac sulfone; IC50 values were 6.16, 52.7, and 71.6 μM, respectively. The present results indicate that sulindac sulfide is a potent inhibitor of CYP4A11. These results and the molecular modeling of CYP4A11 with sulindac sulfide and its oxidized forms suggest that a sulfur atom of sulindac sulfide as well as its carboxylic acid play important roles in the inhibition of CYP4A11.

Crosstalk between adenosine receptors and CYP450-derived oxylipins in the modulation of cardiovascular, including coronary reactive hyperemic response

Adenosine is a ubiquitous endogenous nucleoside or autacoid that affects the cardiovascular system through the activation of four G-protein coupled receptors: adenosine A₁ receptor (A₁AR), adenosine A_2A receptor (A_2AAR), adenosine A_2B receptor (A_2BAR), and adenosine A₃ receptor (A₃AR). With the rapid generation of this nucleoside from cellular metabolism and the widespread distribution of its four G-protein coupled receptors in almost all organs and tissues of the body, this autacoid induces multiple physiological as well as pathological effects, not only regulating the cardiovascular system but also the central nervous system, peripheral vascular system, and immune system. Mounting evidence shows the role of CYP450-enzymes in cardiovascular physiology and pathology, and the genetic polymorphisms in CYP450s can increase susceptibility to cardiovascular diseases (CVDs). One of the most important physiological roles of CYP450-epoxygenases (CYP450-2C & CYP2J2) is the metabolism of arachidonic acid (AA) and linoleic acid (LA) into epoxyeicosatrienoic acids (EETs) and epoxyoctadecaenoic acid (EpOMEs) which generally involve in vasodilation. Like an increase in coronary reactive hyperemia (CRH), an increase in anti-inflammation, and cardioprotective effects. Moreover, the genetic polymorphisms in CYP450-epoxygenases will change the beneficial cardiovascular effects of metabolites or oxylipins into detrimental effects. The soluble epoxide hydrolase (sEH) is another crucial enzyme ubiquitously expressed in all living organisms and almost all organs and tissues. However, in contrast to CYP450-epoxygenases, sEH converts EETs into dihydroxyeicosatrienoic acid (DHETs), EpOMEs into dihydroxyoctadecaenoic acid (DiHOMEs), and others and reverses the beneficial effects of epoxy-fatty acids leading to vasoconstriction, reducing CRH, increase in pro-inflammation, increase in pro-thrombotic and become less cardioprotective. Therefore, polymorphisms in the sEH gene (Ephx2) cause the enzyme to become overactive, making it more vulnerable to CVDs, including hypertension. Besides the sEH, ω-hydroxylases (CYP450-4A11 & CYP450-4F2) derived metabolites from AA, ω terminal-hydroxyeicosatetraenoic acids (19-, 20-HETE), lipoxygenase-derived mid-chain hydroxyeicosatetraenoic acids (5-, 11-, 12-, 15-HETEs), and the cyclooxygenase-derived prostanoids (prostaglandins: PGD₂, PGF_2α; thromboxane: Txs, oxylipins) are involved in vasoconstriction, hypertension, reduction in CRH, pro-inflammation and cardiac toxicity. Interestingly, the interactions of adenosine receptors (A_2AAR, A₁AR) with CYP450-epoxygenases, ω-hydroxylases, sEH, and their derived metabolites or oxygenated polyunsaturated fatty acids (PUFAs or oxylipins) is shown in the regulation of the cardiovascular functions. In addition, much evidence demonstrates polymorphisms in CYP450-epoxygenases, ω-hydroxylases, and sEH genes (Ephx2) and adenosine receptor genes (ADORA1 & ADORA2) in the human population with the susceptibility to CVDs, including hypertension. CVDs are the number one cause of death globally, coronary artery disease (CAD) was the leading cause of death in the US in 2019, and hypertension is one of the most potent causes of CVDs. This review summarizes the articles related to the crosstalk between adenosine receptors and CYP450-derived oxylipins in vascular, including the CRH response in regular salt-diet fed and high salt-diet fed mice with the correlation of heart perfusate/plasma oxylipins. By using A_2AAR^-/-, A₁AR^-/-, eNOS^-/-, sEH^-/- or Ephx2^-/-, vascular sEH-overexpressed (Tie2-sEH Tr), vascular CYP2J2-overexpressed (Tie2-CYP2J2 Tr), and wild-type (WT) mice. This review article also summarizes the role of pro-and anti-inflammatory oxylipins in cardiovascular function/dysfunction in mice and humans. Therefore, more studies are needed better to understand the crosstalk between the adenosine receptors and eicosanoids to develop diagnostic and therapeutic tools by using plasma oxylipins profiles in CVDs, including hypertensive cases in the future.

The role of cytochrome P450 gene rs1126742 polymorphism and risk of hypertension: a systematic review and meta-analysis

BACKGROUND

CYP4A11 gene T8590C (rs1126742) is proved to be an important locus that is relevant to hypertension. Various research on the relationship between rs1126742 polymorphism and hypertension have been published, but due to small sample sizes and limitations of the research objects, the combined results remain controversial.

METHODS

We searched PubMed, Embase, OVID, Web of Science, Wan Fang, and CNKI databases for related articles. Three authors individually extracted data and the quality of studies was evaluated by using the 9-point Newcastle-Ottawa Scale (NOS) independently. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated in different genetic models by using a random-effect model or fixed-effect model according to inter-study heterogeneity. Besides, subgroup analysis and sensitivity analysis were performed and the publication bias was assessed.

RESULTS

There were totally 12 independent case-control studies of 8673 cases and 6611 controls included. Significant associations were found between CYP4A11 gene T8590C polymorphism and hypertension under all genetic models (allele, homozygote, heterozygote, recessive, and dominant model). We also found that there was no obvious relationship between the rs1126742 polymorphism and hypertension in Asian. But positive association has been found in Caucasian in allele, homozygote, and recessive model.

CONCLUSIONS

CYP4A11 gene T8590C (rs1126742) polymorphism increases the occurrence of hypertension, particularly in Caucasian.

Genetic role of CYP4A11 polymorphisms in the risk of developing cardiovascular and cerebrovascular diseases

BACKGROUND

We are interested in comprehensively evaluating the potential genetic influence of rs9332978 A/G, rs1126742 T/C, and rs9333025 G/A polymorphisms of CYP4A11 (cytochrome P450 family 4, subfamily A, member 11) in the risk of developing cardiovascular and cerebrovascular diseases.

METHODS

A meta-analysis was carried out using articles obtained from online databases and Stata/SE 12.0 software. We primarily used a P value of association test (P_association ) and odds ratios (OR) to assess the genetic relationships.

RESULTS

We included 22 eligible case-control articles for our meta-analysis. For the overall meta-analysis of the rs9332978 A/G polymorphism, there was an increased risk of cardiovascular and cerebrovascular diseases in cases under the models of allele G vs. A (P_association  = 0.001, OR = 1.16), AG vs. AA (P_association  < 0.001, OR = 1.22), and AG+GG vs. AA (P_association  < 0.001, OR = 1.22) compared with the controls. There were similar results in the subgroup analysis of "hypertension" (P_association  = 0.024 for the allele model; P_association  = 0.003 for the heterozygote model; and P_association  = 0.005 for the dominant model). For rs1126742, there was a significant difference between cases and controls in the overall meta-analysis and subgroup of "Caucasian," "hypertension," and "population-based (PB)" under all of the genetic models (all P_association  < 0.05, OR > 1). Furthermore, a decreased risk was detected in the overall and "PB" subgroup meta-analysis of rs9333025 under the models of A vs. G, AA vs. GG, and AA vs. GG+GA (all P_association  < 0.05, OR < 1).

CONCLUSION

The rs1126742 T/C polymorphism of CYP4A11 is more likely to be a genetic risk factor for the hypertension cases in the Caucasian population. Moreover, whereas the AG genotype of CYP4A11 rs9332978 may be associated with an increased risk of hypertension, the AA genotype of rs9333025 may be linked to a decreased risk of cardiovascular and cerebrovascular diseases.

A Novel Polymorphism in the Promoter of the CYP4A11 Gene Is Associated with Susceptibility to Coronary Artery Disease

Enzymes CYP4A11 and CYP4F2 are involved in biosynthesis of vasoactive 20-hydroxyeicosatetraenoic acid and may contribute to pathogenesis of coronary artery disease (CAD). We investigated whether polymorphisms of the CYP4A11 and CYP4F2 genes are associated with the risk of CAD in Russian population. DNA samples from 1323 unrelated subjects (637 angiographically confirmed CAD patients and 686 age- and sex-matched healthy individuals) were genotyped for polymorphisms rs3890011, rs9332978, and rs9333029 of CYP4A11 and rs3093098 and rs1558139 of CYP4F2 by using the Mass-ARRAY 4 system. SNPs rs3890011 and rs9332978 of CYP4A11 were associated with increased risk of CAD in women: OR = 1.26, 95% CI: 1.02-1.57, P = 0.004, and Q = 0.01 and OR = 1.45, 95% CI: 1.13-1.87, P = 0.004, and Q = 0.01, respectively. Haplotype G-C-A of CYP4A11 was associated with increased risk of CAD (adjusted OR = 1.41, 95% CI: 1.12-1.78, and P = 0.0036). Epistatic interactions were found between rs9332978 of CYP4A11 and rs1558139 of CYP4F2 (P_interaction = 0.025). In silico analysis allowed identifying that SNP rs9332978 is located at a binding site for multiple transcription factors; many of them are known to regulate the pathways involved in the pathogenesis of CAD. This is the first study in Europeans that reported association between polymorphism rs9332978 of CYP4A11 and susceptibility to coronary artery disease.

20-Hydroxyeicosatetraenoic Acid (HETE)-dependent Hypertension in Human Cytochrome P450 (CYP) 4A11 Transgenic Mice: NORMALIZATION OF BLOOD PRESSURE BY SODIUM RESTRICTION, HYDROCHLOROTHIAZIDE, OR BLOCKADE OF THE TYPE 1 ANGIOTENSIN II RECEPTOR

Male and female homozygous 129/Sv mice carrying four copies of the human cytochrome P450 4A11 gene (CYP4A11) under control of its native promoter (B-129/Sv-4A11(+/+)) develop hypertension (142 ± 8 versus 113 ± 7 mm Hg systolic blood pressure (BP)), and exhibit increased 20-hydroxyeicosatetraenoic acid (20-HETE) in kidney and urine. The hypertension is reversible by a low-sodium diet and by the CYP4A inhibitor HET0016. B-129/Sv-4A11(+/+) mice display an 18% increase of plasma potassium (p < 0.02), but plasma aldosterone, angiotensin II (ANGII), and renin activities are unchanged. This phenotype resembles human genetic disorders with elevated activity of the sodium chloride co-transporter (NCC) and, accordingly, NCC abundance is increased by 50% in transgenic mice, and NCC levels are normalized by HET0016. ANGII is known to increase NCC abundance, and renal mRNA levels of its precursor angiotensinogen are increased 2-fold in B-129/Sv-4A11(+/+), and blockade of the ANGII receptor type 1 with losartan normalizes BP. A pro-hypertensive role for 20-HETE was implicated by normalization of BP and reversal of renal angiotensin mRNA increases by administration of the 20-HETE antagonists 2-((6Z,15Z)-20-hydroxyicosa-6,15-dienamido)acetate or (S)-2-((6Z,15Z)-20-hydroxyicosa-6,15-dienamido)succinate. SGK1 expression is also increased in B-129/Sv-4A11(+/+) mice and paralleled increases seen for NCC. Losartan, HET0016, and 20-HETE antagonists each normalized SGK1 mRNA expression. These results point to a potential 20-HETE dependence of intrarenal angiotensinogen production and ANGII receptor type 1 activation that are associated with increases in NCC and SGK1 and identify elevated P450 4A11 activity and 20-HETE as potential risk factors for salt-sensitive human hypertension by perturbation of the renal renin-angiotensin axis.

Molecular mechanisms and cell signaling of 20-hydroxyeicosatetraenoic acid in vascular pathophysiology

Cytochrome P450s enzymes catalyze the metabolism of arachidonic acid to epoxyeicosatrienoic acids (EETs), dihydroxyeicosatetraenoic acid and hydroxyeicosatetraeonic acid (HETEs). 20-HETE is a vasoconstrictor that depolarizes vascular smooth muscle cells by blocking K+ channels. EETs serve as endothelial derived hyperpolarizing factors. Inhibition of the formation of 20-HETE impairs the myogenic response and autoregulation of renal and cerebral blood flow. Changes in the formation of EETs and 20-HETE have been reported in hypertension and drugs that target these pathways alter blood pressure in animal models. Sequence variants in CYP4A11 and CYP4F2 that produce 20-HETE, UDP-glucuronosyl transferase involved in the biotransformation of 20-HETE and soluble epoxide hydrolase that inactivates EETs are associated with hypertension in human studies. 20-HETE contributes to the regulation of vascular hypertrophy, restenosis, angiogenesis and inflammation. It also promotes endothelial dysfunction and contributes to cerebral vasospasm and ischemia-reperfusion injury in the brain, kidney and heart. This review will focus on the role of 20-HETE in vascular dysfunction, inflammation, ischemic and hemorrhagic stroke and cardiac and renal ischemia reperfusion injury.

20-HETE is associated with unfavorable outcomes in subarachnoid hemorrhage patients

Emerging evidence has suggested that patients experiencing aneurysmal subarachnoid hemorrhage (aSAH) develop vascular dysregulation as a potential contributor to poor outcomes. Preclinical studies have implicated the novel microvascular constrictor, 20-hydroxyeicosatetraenoic acid (20-HETE) in aSAH pathogenesis, yet the translational relevance of 20-HETE in patients with aSAH is largely unknown. The goal of this research was to determine the relationship between 20-HETE cerebrospinal fluid (CSF) levels, gene variants in 20-HETE synthesis, and acute/long-term aSAH outcomes. In all, 363 adult patients (age 18 to 75) with aSAH were prospectively recruited from the University of Pittsburgh Medical Center neurovascular Intensive Care Unit. Patients were genotyped for polymorphic variants and cytochrome P450 (CYP)-eicosanoid CSF levels were measured over 14 days. Outcomes included delayed cerebral ischemia (DCI), clinical neurologic deterioration (CND), and modified Rankin Scores (MRS) at 3 and 12 months. Patients with CND and unfavorable 3-month MRS had 2.2- and 2.7-fold higher mean 20-HETE CSF levels, respectively. Patients in high/moderate 20-HETE trajectory groups (35.7%) were 2.5-, 2.1-, 3.1-, 3.3-, and 2.1-fold more likely to have unfavorable MRS at 3 months, unfavorable MRS at 12 months, mortality at 3 months, mortality at 12 months, and CND, respectively. These results showed that 20-HETE is associated with acute and long-term outcomes and suggest that 20-HETE may be a novel target in aSAH.

20-HETE and blood pressure regulation: clinical implications

20-Hydroxy-5, 8, 11, 14-eicosatetraenoic acid (20-HETE) is a cytochrome P450 (CYP)-derived omega-hydroxylation metabolite of arachidonic acid. 20-HETE has been shown to play a complex role in blood pressure regulation. In the kidney tubules, 20-HETE inhibits sodium reabsorption and promotes natriuresis, thus, contributing to antihypertensive mechanisms. In contrast, in the microvasculature, 20-HETE has been shown to play a pressor role by sensitizing smooth muscle cells to constrictor stimuli and increasing myogenic tone, and by acting on the endothelium to further promote endothelial dysfunction and endothelial activation. In addition, 20-HETE induces endothelial angiotensin-converting enzyme, thus, setting forth a potential feed forward prohypertensive mechanism by stimulating the renin-angiotensin-aldosterone system. With the advancement of gene sequencing technology, numerous polymorphisms in the regulatory coding and noncoding regions of 20-HETE-producing enzymes, CYP4A11 and CYP4F2, have been associated with hypertension. This in-depth review article discusses the biosynthesis and function of 20-HETE in the cardiovascular system, the pharmacological agents that affect 20-HETE action, and polymorphisms of CYP enzymes that produce 20-HETE and are associated with systemic hypertension in humans.

Association between the CYP4A11 T8590C variant and essential hypertension: new data from Han Chinese and a meta-analysis

Objective

CYP4A11 oxidizes endogenous arachidonic acid to 20-hydroxyeicosatetraenoic acid, a renal vasoconstrictor and natriuretic in humans. Previous studies demonstrated an association between a functional variant (T8590C) of CYP4A11 and essential hypertension, though with conflicting results. To elucidate this relationship, a case-control study and meta-analysis were performed to assess the possible association of essential hypertension with CYP4A11 genetic variations.

Methods

Associations between the T8590C polymorphism and essential hypertension were examined in 328 unrelated cases and 297 age-matched controls in Han Chinese individuals. High-resolution melting was used to identify the CYP4A11 variant. To further investigate the association, we conducted a meta-analysis including eight studies published previously in July 2012.

Results

The frequency of the CYP4A11 T8590C polymorphism showed no significant difference between cases and controls (all P>0.05). However, the meta-analysis showed that the CYP4A11 T8590C polymorphism may increase the risk of essential hypertension in an additive model (OR: 1.15, 95% CI: 1.02–1.29, P = 0.02), a dominant model (OR: 1.06, 95% CI: 1.01–1.32, P = 0.03), a recessive model (OR: 1.52, 95% CI: 1.15–2.02, P = 0.003) and a homozygote contrast (OR: 1.38, 95% CI: 1.07–1.78, P = 0.01). Also, a significant relationship was observed among Caucasians in the additive model, the homozygote contrast, the recessive model and the dominant model (all P<0.05). However, no association was observed in an Asian population (all P>0.05).

Conclusions

This meta-analysis suggests there is a significant association between the CYP4A11 T8590C variant and essential hypertension, especially in Caucasians. The case-control study did not find a significant association among the Han Chinese population, but the controls were poorly matched and meaningful conclusions cannot therefore be made. Further large-scale studies are needed to clarify whether the CYP4A11 T8590C polymorphism is associated with hypertension risk in Asians or has a gender-specific effect.

Genetic associations with hypertension: meta-analyses of six candidate genetic variants

AIMS

The aim of this study was to perform combined analyses of six genetic variants for the risk of hypertension.

METHODS

After a comprehensive literature search for genetic variants involved with the association study of hypertension, we harvested a total of five genes (six variants) for the current meta-analyses. These genes consisted of CYP4A11 (T8590C), RGS2 (1891-1892del TC and G638A), HTR2A (T102C), GNAS (T393C), and HSD3B1 (T→C Leu338).

RESULTS

A total of 20 studies among 13,816 cases and 19,248 controls were retrieved for the meta-analyses of six genetic variants. It was shown that the RGS2 1891-1892del TC (OR=1.10, 95% CI=1.02-1.19, p=0.02) polymorphism and the CYP4A11 T8590C (OR=1.19, 95% CI=1.00-1.41, p=0.05) polymorphism were significantly associated with increased risk of hypertension. No association was found between the other four variants and the risk of hypertension.

CONCLUSION

This meta-analysis revealed that the RGS2 1891-1892del TC polymorphism and CYP4A11 T8590C polymorphism were associated with hypertension risk. However, HSD3B1 T→C Leu338, HTR2A T102C, GNAS T393C, and RGS2 G638A polymorphisms were not associated with hypertension risk.

Haplotype-based case-control study of CYP4A11 gene and myocardial infarction

CYP4A11, which is a member of the cytochrome P450 family, acts mainly as an enzyme that converts arachidonic acid to 20-hydroxyeicosatetraenoic acid (20-HETE), a metabolite involved in the maintenance of cardiovascular health. Recently, it was reported that many subfamilies of CYP genes have an association with myocardial infarction (MI). The aim of the present study was to assess the association between the human CYP4A11 gene and MI, using a haplotype-based case-control study with a separate analysis of the gender groups. A total of 239 MI patients and 285 controls were genotyped for 3 single-nucleotide polymorphisms (SNPs) of the human CYP4A11 gene (rs2269231, rs1126742, rs9333025). The data obtained via haplotype-based case-control studies were assessed for 3 separate groups: total subjects, men, and women. For the total, men and women groups, the distribution of the genotypes and alleles of the 3 SNPs did not show any significant difference between the MI patients and the control subjects. For the total and the men groups, the overall distribution of the haplotypes constructed with the 3 SNPs significantly differed between the MI patients and control subjects (P < 0.001). Also, for the total and for the men, the frequency of the T-T-A haplotype constructed with the 3 SNPs was significantly lower for the MI patients than for the control subjects (both P < 0.001). The T-T-A haplotype constructed with the 3 SNPs appears to be a protective genetic marker for MI in Japanese men.

Role of 20-HETE in the antihypertensive effect of transfer of chromosome 5 from Brown Norway to Dahl salt-sensitive rats

This study examined whether substitution of chromosome 5 containing the CYP4A genes from Brown Norway rat onto the Dahl S salt-sensitive (SS) genetic background upregulates the renal production of 20-HETE and attenuates the development of hypertension. The expression of CYP4A protein and the production of 20-HETE were significantly higher in the renal cortex and outer medulla of SS.5(BN) (chromosome 5-substituted Brown Norway rat) consomic rats fed either a low-salt (LS) or high-salt (HS) diet than that seen in SS rats. The increase in the renal production of 20-HETE in SS.5(BN) rats was associated with elevated expression of CYP4A2 mRNA. MAP measured by telemetry rose from 117 ± 1 to 183 ± 5 mmHg in SS rats fed a HS diet for 21 days, but only increased to 151 ± 5 mmHg in SS.5(BN) rats. The pressure-natriuretic and diuretic responses were twofold higher in SS.5(BN) rats compared with SS rats. Protein excretion rose to 354 ± 17 mg/day in SS rats fed a HS diet for 21 days compared with 205 ± 13 mg/day in the SS.5(BN) rats, and the degree of glomerular injury was reduced. Baseline glomerular capillary pressure (Pgc) was similar in SS.5(BN) rats (43 ± 1 mmHg) and Dahl S (44 ± 2 mmHg) rats. However, Pgc increased to 59 ± 3 mmHg in SS rats fed a HS diet for 7 days, while it remained unaltered in SS.5(BN) rats (43 ± 2 mmHg). Chronic administration of an inhibitor of the synthesis of 20-HETE (HET0016, 10 mg·kg(-1)·day(-1) iv) reversed the antihypertensive phenotype seen in the SS.5(BN) rats. These findings indicate that the transfer of chromosome 5 from the BN rat onto the SS genetic background increases the renal expression of CYP4A protein and the production of 20-HETE and that 20-HETE contributes to the antihypertensive and renoprotective effects seen in the SS.5(BN) consomic strain.

A novel polymorphism of the CYP4A11 gene is associated with coronary artery disease

BACKGROUND

CYP4A11 (cytochrome P450, family 4, subfamily A, polypeptide 11) converts arachidonic acid to 20-hydroxyeicosatetraenoic acid (20-HETE), which plays a crucial role in the modulation of cardiovascular homeostasis. The aim of the present study was to assess the association between the human CYP4A11 gene and coronary artery disease (CAD).

METHODS

A total of 361 patients with CAD and 315 controls were genotyped for 4 single-nucleotide polymorphisms (SNPs) of the human CYP4A11 gene (rs9332978, rs4660980, rs3890011, and rs1126742). The data were assessed for 3 groups: total participants, men, and women via case-control studies.

RESULTS

For total participants and men, the distribution of SNP3 (rs3890011) genotypes showed a significant difference between CAD and control participants (P = .030 and P = .013, respectively), the distribution of the recessive model of SNP3 (GG vs CC + GC) was significantly higher in CAD patients than in control participants (P = .011 and P = .014, respectively), the significant difference was retained after adjustment for covariates (for total participants, 95% confidence interval [CI]: 1.137-2.423, P = .009; and for males, 95% CI: 1.173-3.013, P = .009).

CONCLUSIONS

rs3890011 maybe a novel polymorphism of the CYP4A11 gene associated with CAD in a Han Chinese population.

CYP4A11 variant is associated with high-density lipoprotein cholesterol in women

The ω-hydroxylase CYP4A11 catalyzes the transformation of epoxyeicosatrienoic acids to omega-hydroxylated-epoxyeicosatrienoic acids, endogenous peroxisome proliferator-activated receptor α (PPARα) agonists. PPARα activation increases high-density lipoprotein-cholesterol (HDL-C). A cytosine-for-thymidine (T8590C) variant of CYP4A11 encodes for a ω-hydroxylase with reduced activity. This study examined the relationship between CYP4A11 T8590C genotype and metabolic parameters in the Framingham Offspring Study and in a clinical practice-based biobank, BioVU. In women in the Framingham Offspring Study, the CYP4A11 8590C allele was associated with reduced HDL-C concentrations (54.2±0.9 mg/dL in CYP4A11 CC or CT genotype women versus 56.7±0.5 mg/dL in TT women, p=0.02), and with an increased prevalence of low HDL-C, defined categorically as ≤50mg/dL [odds ratio 1.39 (95% CI 1.02-1.90), p=0.04]. In the BioVU cohort, the CYP4A11 8590C allele was also associated with low HDL-C in women [odds ratio 1.69 (95% CI 1.03-2.77, p=0.04)]. There was no relationship between genotype and HDL-C in men in either cohort.

Arachidonic acid ω-hydroxylase CYP4A11: inter-ethnic variations in the 8590T>C loss-of-function variant

The human Cytochrome P450 4A11 (CYP4A11) is a major ω-hydroxylase involved in the regulation of blood pressure in the kidney through the conversion of arachidonic acid into 20-hydroxyeicosatetraenoic acid (20-HETE). Previous studies have reported a significant association between the 8590T>C genetic variant of CYP4A11 and hypertension. Interestingly, several population-based studies have reported ethnic differences in the prevalence of hypertension, with the highest prevalence in African populations. The aim of this work was to determine the frequency and inter-ethnic comparison of the CYP4A11 (8590T>C) functional polymorphism, in five new ethnic groups: European (99 French Caucasians), African (36 Gabonese and 50 Senegalese), South American (60 Peruvians) and North African (53 Tunisians) populations, using polymerase chain reaction-single strand conformational polymorphism and sequencing strategies. We confirmed that the CYP4A11 (8590T>C) functional polymorphism exhibits inter-ethnic frequency differences. Noteworthy, the highest 8590C allele frequency was observed in the Tunisian (30.2%), followed by Senegalese (20%) populations. In addition, the CC genotype was only found in the Gabonese and Tunisian populations (5.6% and 8.4%, respectively). These populations may be of major interest to help to clarify the linkage between hypertension and CYP4A11 (8590T>C) genotype in African populations. These findings provide data for further studies that investigate the potential association of CYP4A11 (8590T>C) variant with an incidence of hypertension genesis in respect of ethnicity.

20-hydroxyeicosatetraeonic acid: a new target for the treatment of hypertension

Arachidonic acid is metabolized by enzymes of the CYP4A and 4F families to 20-hydroxyeicosatetraeonic acid (20-HETE), which plays an important role in the regulation of renal function, vascular tone, and the long-term control of arterial pressure. In the vasculature, 20-HETE is a potent vasoconstrictor, and upregulation of the production of this compound contributes to the elevation in oxidative stress and endothelial dysfunction and the increase in peripheral vascular resistance associated with some forms of hypertension. In kidney, 20-HETE inhibits Na transport in the proximal tubule and thick ascending loop of Henle, and deficiencies in the renal formation of 20-HETE contributes to sodium retention and development of some salt-sensitive forms of hypertension. 20-HETE also has renoprotective actions and opposes the effects of transforming growth factor β to promote proteinuria and renal end organ damage in hypertension. Several new inhibitors of the synthesis of 20-HETE and 20-HETE agonists and antagonists have recently been developed. These compounds along with peroxisome proliferator-activated receptor-α agonists that induce the renal formation of 20-HETE seem to have promise as antihypertensive agents. This review summarizes the rationale for the development of drugs that target the 20-HETE pathway for the treatment of hypertension and associated cardiovascular complications.

Effect of cytochrome P450 polymorphism on arachidonic acid metabolism and their impact on cardiovascular diseases

Cardiovascular diseases (CVDs) remain the leading cause of death in the developed countries. Taking into account the mounting evidence about the role of cytochrome P450 (CYP) enzymes in cardiovascular physiology, CYP polymorphisms can be considered one of the major determinants of individual susceptibility to CVDs. One of the important physiological roles of CYP enzymes is the metabolism of arachidonic acid. CYP epoxygenases such as CYP1A2, CYP2C, and CYP2J2 metabolize arachidonic acid to epoxyeicosatrienoic acids (EETs) which generally possess vasodilating, anti-inflammatory, anti-apoptotic, anti-thrombotic, natriuretic, and cardioprotective effects. Therefore, genetic polymorphisms causing lower activity of these enzymes are generally associated with an increased risk of several CVDs such as hypertension and coronary artery disease. EETs are further metabolized by soluble epoxide hydrolase (sEH) to the less biologically active dihydroxyeicosatrienoic acids (DHETs). Therefore, sEH polymorphism has also been shown to affect arachidonic acid metabolism and to be associated with CVDs. On the other hand, CYP omega-hydroxylases such as CYP4A11 and CYP4F2 metabolize arachidonic acid to 20-hydroxyeicosatetraenoic acid (20-HETE) which has both vasoconstricting and natriuretic effects. Genetic polymorphisms causing lower activity of these enzymes are generally associated with higher risk of hypertension. Nevertheless, some studies have denied the association between polymorphisms in the arachidonic acid pathway and CVDs. Therefore, more research is needed to confirm this association and to better understand the pathophysiologic mechanisms behind it.