Genotype polymorphisms of GGCX, NQO1, and VKORC1 genes associated with risk susceptibility in patients with large-artery atherosclerotic stroke

Mechanisms of Small Intestine Involvement in Obesity-Induced Atherosclerosis

Purpose

Studies have shown that atherosclerotic plaques are associated with changes in the microbial composition of the intestinal flora and obesity, and that the small intestine plays an irreplaceable role in regulating intestinal flora homeostasis, but the role of the small intestine in the development of obesity-related atherosclerosis remains understudied. Therefore, this study explores the role of the small intestine in obesity-induced atherosclerosis and its molecular mechanisms.

Methods

In the GSE59054 data, small intestine tissue samples from 3 normal and 3 obese mice were analyzed using bioinformatics methods. Screening for differentially expressed genes (DEGs) using the GEO2R tool. The DEGs were next processed for bioinformatics analysis. We constructed an obese mouse model and measured aortic arch pulse wave velocity (PWV). Aortic and small intestine tissues were stained with hematoxylin-eosin (HE) to observe pathological changes. Finally, immunohistochemistry was performed to verify the expression of small intestinal proteins.

Results

We identified a total of 122 DEGs. Pathway analysis revealed that BMP4, CDH5, IL1A, NQO1, GSTM1, GSTA3, CAV1 and MGST2 were mainly enriched in the Fluid shear stress and atherosclerosis pathway. In addition, BMP4, NQO1 and GSTM1 are closely related to atherosclerosis. Ultrasound and pathological findings suggest the presence of obesity atherosclerosis. Immunohistochemistry verified high expression of BMP4 and low expression of NQO1 and GSTM1 in obese small intestine tissues.

Conclusion

The altered expression of BMP4, NQO1 and GSTM1 in small intestine tissues during obesity may be related to atherosclerosis, and Fluid shear stress and atherosclerosis pathway may be the molecular mechanism of their role.

Bioinformatics Analysis of Next Generation Sequencing Data Identifies Molecular Biomarkers Associated With Type 2 Diabetes Mellitus

Background

Type 2 diabetes mellitus (T2DM) is the most common metabolic disorder. The aim of the present investigation was to identify gene signature specific to T2DM.

Methods

The next generation sequencing (NGS) dataset GSE81608 was retrieved from the gene expression omnibus (GEO) database and analyzed to identify the differentially expressed genes (DEGs) between T2DM and normal controls. Then, Gene Ontology (GO) and pathway enrichment analysis, protein-protein interaction (PPI) network, modules, miRNA (micro RNA)-hub gene regulatory network construction and TF (transcription factor)-hub gene regulatory network construction, and topological analysis were performed. Receiver operating characteristic curve (ROC) analysis was also performed to verify the prognostic value of hub genes.

Results

A total of 927 DEGs (461 were up regulated and 466 down regulated genes) were identified in T2DM. GO and REACTOME results showed that DEGs mainly enriched in protein metabolic process, establishment of localization, metabolism of proteins, and metabolism. The top centrality hub genes APP, MYH9, TCTN2, USP7, SYNPO, GRB2, HSP90AB1, UBC, HSPA5, and SQSTM1 were screened out as the critical genes. ROC analysis provides prognostic value of hub genes.

Conclusion

The potential crucial genes, especially APP, MYH9, TCTN2, USP7, SYNPO, GRB2, HSP90AB1, UBC, HSPA5, and SQSTM1, might be linked with risk of T2DM. Our study provided novel insights of T2DM into genetics, molecular pathogenesis, and novel therapeutic targets.

Identification of biomarkers, pathways, and potential therapeutic targets for heart failure using next-generation sequencing data and bioinformatics analysis

BACKGROUND

Heart failure (HF) is the most common cardiovascular diseases and the leading cause of cardiovascular diseases related deaths. Increasing molecular targets have been discovered for HF prognosis and therapy. However, there is still an urgent need to identify novel biomarkers. Therefore, we evaluated biomarkers that might aid the diagnosis and treatment of HF.

METHODS

We searched next-generation sequencing (NGS) dataset (GSE161472) and identified differentially expressed genes (DEGs) by comparing 47 HF samples and 37 normal control samples using limma in R package. Gene ontology (GO) and pathway enrichment analyses of the DEGs were performed using the g: Profiler database. The protein-protein interaction (PPI) network was plotted with Human Integrated Protein-Protein Interaction rEference (HiPPIE) and visualized using Cytoscape. Module analysis of the PPI network was done using PEWCC1. Then, miRNA-hub gene regulatory network and TF-hub gene regulatory network were constructed by Cytoscape software. Finally, we performed receiver operating characteristic (ROC) curve analysis to predict the diagnostic effectiveness of the hub genes.

RESULTS

A total of 930 DEGs, 464 upregulated genes and 466 downregulated genes, were identified in HF. GO and REACTOME pathway enrichment results showed that DEGs mainly enriched in localization, small molecule metabolic process, SARS-CoV infections, and the citric acid tricarboxylic acid (TCA) cycle and respiratory electron transport. After combining the results of the PPI network miRNA-hub gene regulatory network and TF-hub gene regulatory network, 10 hub genes were selected, including heat shock protein 90 alpha family class A member 1 (HSP90AA1), arrestin beta 2 (ARRB2), myosin heavy chain 9 (MYH9), heat shock protein 90 alpha family class B member 1 (HSP90AB1), filamin A (FLNA), epidermal growth factor receptor (EGFR), phosphoinositide-3-kinase regulatory subunit 1 (PIK3R1), cullin 4A (CUL4A), YEATS domain containing 4 (YEATS4), and lysine acetyltransferase 2B (KAT2B).

CONCLUSIONS

This discovery-driven study might be useful to provide a novel insight into the diagnosis and treatment of HF. However, more experiments are needed in the future to investigate the functional roles of these genes in HF.

Review on NAD(P)H dehydrogenase quinone 1 (NQO1) pathway

NQO1 is an enzyme present in humans which is encoded by NQO1 gene. It is a protective antioxidant agent, versatile cytoprotective agent and regulates the oxidative stresses of chromatin binding proteins for DNA damage in cancer cells. The oxidization of cellular pyridine nucleotides causes structural alterations to NQO1 and changes in its capacity to binding of proteins. A strategy based on NQO1 to have protective effect against cancer was developed by organic components to enhance NQO1 expression. The quinone derivative compounds like mitomycin C, RH1, E09 (Apaziquone) and β-lapachone causes cell death by NQO1 reduction of two electrons. It was also known to be overexpressed in various tumor cells of breast, lung, cervix, pancreas and colon when it was compared with normal cells in humans. The mechanism of NQO1 by the reduction of FAD by NADPH to form FADH2 is by two ways to inhibit cancer cell development such as suppression of carcinogenic metabolic activation and prevention of carcinogen formation. The NQO1 exhibit suppression of chemical-mediated carcinogenesis by various properties of NQO1 which includes, detoxification of quinone scavenger of superoxide anion radical, antioxidant enzyme, protein stabilizer. This review outlines the NQO1 structure, mechanism of action to inhibit the cancer cell, functions of NQO1 against oxidative stress, drugs acting on NQO1 pathways, clinical significance.

Association of Vitamin K Insufficiency With Cognitive Dysfunction in Community-Dwelling Older Adults

Vitamin K is a fat-soluble vitamin shown to be associated with several age-related diseases. Although a small number of epidemiological studies described the relationship between vitamin K status and cognitive impairment, vitamin K status was estimated by relatively special methods in previous reports. Here, we demonstrated the association of the concentration of undercarboxylated osteocalcin (ucOC) in serum, which is a biomarker for vitamin K insufficiency, with cognitive function in a cross-sectional study. A total of 800 community-dwelling older adults (mean age = 75.9) were invited to geriatric health examination, including a Mini-Mental State Examination (MMSE) and a blood test. By using binary logistic regression analysis, the risk of cognitive impairment equivalent or below the mild cognitive impairment level for each tertile of ucOC was examined, with the lowest tertile as the reference. We found a significant association of impaired cognitive function and concentration of ucOC in the highest tertile of ucOC, with the odds ratio of 1.65 (95% CI, 1.06 to 2.59, P = 0.028). When the analysis was repeated with each domain of MMSE, the highest tertile of ucOC was associated with impaired orientation, calculation, and language. As far as we know, this is the first report on the significant association of single ucOC measurement and cognitive impairment. Our analysis also suggests that vitamin K insufficiency could be associated with selected categories of cognitive function. Since the single measurement of ucOC in serum is a simple and widely available method for vitamin K evaluation, it could be useful as a biomarker of neurodegenerative diseases affecting the cognitive functions.

Roles of NAD(P)H:quinone Oxidoreductase 1 in Diverse Diseases

NAD(P)H:quinone oxidoreductase (NQO) is an antioxidant flavoprotein that catalyzes the reduction of highly reactive quinone metabolites by employing NAD(P)H as an electron donor. There are two NQO enzymes—NQO1 and NQO2—in mammalian systems. In particular, NQO1 exerts many biological activities, including antioxidant activities, anti-inflammatory effects, and interactions with tumor suppressors. Moreover, several recent studies have revealed the promising roles of NQO1 in protecting against cardiovascular damage and related diseases, such as dyslipidemia, atherosclerosis, insulin resistance, and metabolic syndrome. In this review, we discuss recent developments in the molecular regulation and biochemical properties of NQO1, and describe the potential beneficial roles of NQO1 in diseases associated with oxidative stress.

Influence of NQO1 Polymorphisms on Warfarin Maintenance Dose: A Systematic Review and Meta-Analysis (rs1800566 and rs10517)

This meta-analysis was conducted to analyze the effect of NQO1 polymorphism on the warfarin maintenance dosage. Using strict inclusion and exclusion criteria, we searched PubMed, EMBASE, and the Cochrane Library for eligible studies published prior to July 7, 2021. The required data were extracted, and experts were consulted when necessary. Review Manager Version 5.4 software was used to analyze the relationship between NQO1 polymorphisms and the warfarin maintenance dosage. Four articles involving 757 patients were included in the meta-analysis. Patients who were NQO1 rs10517 G carriers (AG carriers or GG carriers) required a 48% higher warfarin maintenance dose than those who were AA carriers. Patients with NQO1 rs1800566 CT carriers required a 13% higher warfarin dose than those who were CC carriers, with no associations observed with the other comparisons of the NQO1 rs1800566 genotypes. However, the results obtained by comparing the NQO1 rs1800566 genotypes require confirmation, as significant changes in the results were found in sensitivity analyses. Our meta-analysis suggests that the NQO1 rs10517and NQO1 rs1800566 variant statuses affect the required warfarin maintenance dose.

Multi-site Investigation of Genetic Determinants of Warfarin Dose Variability in Latinos

We conducted a multi‐site investigation of genetic determinants of warfarin dose variability in Latinos from the U.S. and Brazil. Patients from four institutions in the United States (n = 411) and Brazil (n = 663) were genotyped for VKORC1 c.‐1639G> A, common CYP2C9 variants, CYP4F2*3, and NQO1*2. Multiple regression analysis was used in the U.S. cohort to test the association between warfarin dose and genotype, adjusting for clinical factors, with further testing in an independent cohort of Brazilians. In the U.S. cohort, VKORC1 and CYP2C9 variants were associated with lower warfarin dose (β = −0.29, P < 2.0 × 10⁻¹⁶; β = −0.21, P = 4.7 × 10⁻⁷, respectively) whereas CYP4F2 and NQO1 variants were associated with higher dose (β = 0.10, P = 2 × 10⁻⁴; β = 0.10, P = 0.01, respectively). Associations with VKORC1 (β = −0.14, P = 2.0 × 10⁻¹⁶), CYP2C9 (β = −0.07, P = 5.6 × 10⁻¹⁰), and CYP4F2 (β = 0.03, P = 3 × 10⁻³), but not NQO1*2 (β = 0.01, P = 0.30), were replicated in the Brazilians, explaining 43–46% of warfarin dose variability among the cohorts from the U.S. and Brazil, respectively. We identified genetic associations with warfarin dose requirements in the largest cohort of ancestrally diverse, warfarin‐treated Latinos from the United States and Brazil to date. We confirmed the association of variants in VKORC1, CYP2C9, and CYP4F2 with warfarin dose in Latinos from the United States and Brazil.

The expression of zebrafish NAD(P)H:quinone oxidoreductase 1(nqo1) in adult organs and embryos

NQO1, NAD(P)H: quinone oxidoreductase 1, was first identified in rat and its role has been extensively studied. Even the roles of NQO1 in the maintenance of physiological function and disease were largely addressed, whether the tissue specific functions of the NQO1 in organ development remains unknown. In the current study, we identified two NQO1 isoforms (isoform 1 and isoform 2) and examined the expression of nqo1 variants in adult zebrafish organs and embryos at different stages. In adult organs, RT-PCR result indicated that nqo1 variant 1 was mainly expressed in stomach and intestine, while nqo1 variant 2 was expressed in all organs investigated except for heart. Further, RT-PCR result showed that the nqo1 variant 1 and variant 2 were expressed at all the embryonic stages, but nqo1 variant 1 expression level was much lower than that of nqo1 variant 2. To specifically examine the expression pattern of these two different nqo1 variants, we did whole mount in situ hybridization and the results demonstrated that, both of them were maternally expressed at 8-cell stage, and they were all expressed ubiquitously at early stage. At 24 hpf, nqo1 variant 2 was mainly expressed in yolk cells, and slightly in head and eyes. At 48 hpf, nqo1 variant 2 was restricted in lateral line neuromasts. From 72 hpf to 144 hpf, nqo1 variant 2 was mainly restricted in branchial arch, liver, swimming bladder and lateral line neuromasts, while from 124 hpf to 192 hpf, nqo1 variant 2 only restricted in liver, and disappeared in lateral line neuromasts. On the contrary, at the late embryonic stage, nqo1 variant 1 was only expressed in liver and swimming bladder while not in branchial arch and lateral line neuromasts. In conclusion, we systematically analyzed the expression pattern of nqo1 variant 1 and variant 2 in zebrafish at different embryonic stages, and our data implied the possible role of nqo1 in regulating liver, branchial arch and lateral neuromasts development.

NQO1: A target for the treatment of cancer and neurological diseases, and a model to understand loss of function disease mechanisms

NAD(P)H quinone oxidoreductase 1 (NQO1) is a multi-functional protein that catalyses the reduction of quinones (and other molecules), thus playing roles in xenobiotic detoxification and redox balance, and also has roles in stabilising apoptosis regulators such as p53. The structure and enzymology of NQO1 is well-characterised, showing a substituted enzyme mechanism in which NAD(P)H binds first and reduces an FAD cofactor in the active site, assisted by a charge relay system involving Tyr-155 and His-161. Protein dynamics play important role in physio-pathological aspects of this protein. NQO1 is a good target to treat cancer due to its overexpression in cancer cells. A polymorphic form of NQO1 (p.P187S) is associated with increased cancer risk and certain neurological disorders (such as multiple sclerosis and Alzheimer´s disease), possibly due to its roles in the antioxidant defence. p.P187S has greatly reduced FAD affinity and stability, due to destabilization of the flavin binding site and the C-terminal domain, which leading to reduced activity and enhanced degradation. Suppressor mutations partially restore the activity of p.P187S by local stabilization of these regions, and showing long-range allosteric communication within the protein. Consequently, the correction of NQO1 misfolding by pharmacological chaperones is a viable strategy, which may be useful to treat cancer and some neurological conditions, targeting structural spots linked to specific disease-mechanisms. Thus, NQO1 emerges as a good model to investigate loss of function mechanisms in genetic diseases as well as to improve strategies to discriminate between neutral and pathogenic variants in genome-wide sequencing studies.

NQO1 C609T Polymorphism is Associated with Coronary Artery Disease in a Gender-Dependent Manner

Findings on the association of NQO1 C609T polymorphism in the NQO1 gene and cardiovascular disease susceptibility are controversial. The objective of the current study was to examine the relationship between this polymorphism and the presence and severity of angiographically determined coronary artery disease (CAD). One-hundred and forty-five patients with newly diagnosed angiographically documented CAD (≥50 % luminal stenosis of any coronary vessel) as case group were compared to 139 controls (subjects with no luminal stenosis at coronary arteries). The presence of C609T polymorphism was analyzed using polymerase chain reaction-based restriction fragment length polymorphism. Among total population, those with combined CT/TT (T allele carrier) genotype showed a trend toward lower odds of CAD compared to those with CC (wild type) genotype, but it did not reach a statistically significant level (p = 0.061). When data were analyzed separately for men or women, CT + TT group as compared to CC genotype was associated with decreased odds of CAD in women (adjusted OR 0.4, 95 % CI 0.2-0.9; p = 0.043), but not in men (adjusted OR 0.8, 95 % CI 0.3-1.9; p = 0.612). The C609T polymorphism within NQO1 is independently associated with CAD in women, but no association was observed in whole study population or in men.

G-1639A but Not C1173T VKORC1 Gene Polymorphism Is Related to Ischemic Stroke and Its Various Risk Factors in Ukrainian Population

Vitamin K epoxide reductase complex subunit 1 (VKORC1) is integral 163-amino acid long transmembrane protein which mediates recycling of vitamin K 2,3-epoxide to vitamin K hydroquinone and it is necessary for activation of vitamin K-dependent proteins (VKDPs). Herein, the association between G-1639A (rs9923231) and C1173T (rs9934438) single-nucleotide polymorphisms (SNPs) of the VKORC1 gene and ischemic stroke (IS) was tested in Ukrainian population. Genotyping was performed in 170 IS patients and 124 control subjects (total 294 DNA samples) using PCR-RFLP (polymerase chain reaction with following restriction fragment length polymorphism analysis) method. Our data showed that G-1639A but not C1173T polymorphism was related to IS, regardless of adjustment for age, sex, body mass index, smoking status, and arterial hypertension. The risk for IS in -1639A allele carriers (OR = 2.138, P = 0.015) was higher than in individuals with G/G genotype. Haplotype analysis demonstrated that -1639G/1173T and -1639A/1173C were related to increased risk for IS (OR = 3.813, P = 0.010, and OR = 2.189, P = 0.011, resp.), while -1639G/1173C was a protective factor for IS (OR = 0.548, P < 0.001). Obtained results suggested that -1639A allele can be a possible genetic risk factor for IS in Ukrainian population.

Association of Nuclear Factor-Erythroid 2-Related Factor 2, Thioredoxin Interacting Protein, and Heme Oxygenase-1 Gene Polymorphisms with Diabetes and Obesity in Mexican Patients

The nuclear factor-erythroid 2- (NF-E2-) related factor 2 (Nrf2) is abated and its ability to reduce oxidative stress is impaired in type 2 diabetes and obesity. Thus, the aim of this study was to explore if polymorphisms in Nrf2 and target genes are associated with diabetes and obesity in Mexican mestizo subjects. The rs1800566 of NAD(P)H:quinone oxidoreductase 1 (NQO1) gene, rs7211 of thioredoxin interacting protein (TXNIP) gene, rs2071749 of heme oxygenase-1 (HMOX1) gene, and the rs6721961 and the rs2364723 from Nrf2 gene were genotyped in 627 diabetic subjects and 1020 controls. The results showed that the rs7211 polymorphism is a protective factor against obesity in nondiabetic subjects (CC + CT versus TT, OR = 0.40, P = 0.005) and in women (CC versus CT + TT, OR = 0.7, P = 0.016). TT carriers had lower high-density lipoprotein cholesterol levels and lower body mass index. The rs2071749 was positively associated with obesity (AA versus AG + GG, OR = 1.25, P = 0.026). Finally, the rs6721961 was negatively associated with diabetes in men (CC versus CA + AA, OR = 0.62, P = 0.003). AA carriers showed lower glucose concentrations. No association was found for rs1800566 and rs2364723 polymorphisms. In conclusion, the presence of Nrf2 and related genes polymorphisms are associated with diabetes and obesity in Mexican patients.

Effects of NAD(P)H quinone oxidoreductase 1 polymorphisms on stable warfarin doses in Korean patients with mechanical cardiac valves

PURPOSE

NAD(P)H dehydrogenase, encoded by NAD(P)H quinone oxidoreductase 1 (NQO1), is an enzyme that catalyzes the reduction of quinones, including vitamin K. Given its potential role in vitamin K metabolism, this study aimed to investigate the effects of NQO1 polymorphisms on stable warfarin doses.

METHODS

We tested a possible effect of gene polymorphisms on variability in warfarin response using 206 Korean patients with mechanical cardiac valves. Single nucleotide polymorphisms (SNPs) of NQO1 with a minor allele frequency of at least 15% were included. Also, genotypes of vitamin K epoxide reductase complex subunit 1 (VKORC1), cytochrome P450 (CYP) 2C9, CYP4F2, gamma-glutamyl carboxylase (GGCX), and GATA4 were determined.

RESULTS

NQO1 rs1800566 (C>T) and rs10517 (C>T) were significantly associated with stable warfarin doses. Variant homozygote carriers required lower stable warfarin doses than those with wild-type C allele in rs1800566 (4.85 ± 1.61 vs. 5.61 ± 1.94 mg; p = 0.033), whereas patients with wild homozygote required lower doses than those with T allele in rs10517 (5.11 ± 1.73 vs. 5.75 ± 1.98 mg; p = 0.017). Similar results were obtained from stratified analysis using VKORC1 variant homozygote carriers in both SNPs. Multivariate analysis showed that rs10517 (C>T) increased contribution of gene variations to the overall warfarin dose variability from 42.5 to 43.8%.

CONCLUSION

Our results demonstrate that NQO1 gene polymorphisms influence stable warfarin doses in Korean patients.

[Association of allelic polymorphisms of genes matrix Gla-protein system with ischemic atherothrombotic stroke]

There are results of the determination of 10 polymorphisms of matrix Gla-protein system (gene MGP-T(-138)-->C (rs1800802), G(-7)-->A (rs1800801), Thr83-->Ala (rs4236), gene VDR-FokI (rs2228570), BsmI (rs1544410), ApaI (rs7975232), TaqI (rs731236), gene GGCX-Arg325-->Gln (rs699664), gene VKORS1-T(2255)-->C (rs2359612), gene BMP-2-Ser37-->Ala (rs2273073)) into 170 patients with ischemic atherothrombotic stroke (IATS) and 124 healthy individual is (control group). It is established that there is a connection between the IATS and polymorphic variants of genes MGP (G(-7)-->A) and VKORC1 (T(2255)-->C). The risk of IATS in carriers of minor allele A/A (G(-7)-->A polymorphism) in 2.6 times higher than in carriers of the major allele (G/A + G/G), and C/C genotype (T(2255)-->C polymorphism) in 2.2 times higher than the homozygotes of major allele. The coincidence of patients T/C and G/G, C/C and G/A genotypes, and A/A genotype (G(-7)-->A polymorphism) with any genotype T(2255)-->C polymorphism are increases the risk of IATS.

Association of functional VKORC1 promoter polymorphism with occurrence and clinical aspects of ischemic stroke in a Greek population

Genetic factors are considered to play an important role in determining the susceptibility to the occurrence, clinical course, and functional outcome of an acute ischemic stroke (IS). Undercarboxylation of specific vitamin K-dependent proteins, due to genetic polymorphisms of VKORC1, can affect both vascular calcification and thrombogenicity. We sought to determine the association of VKORC1 −1639G > A polymorphism with IS incidence, age of onset, severity of disease, and functional outcome after an acute IS. VKORC1 −1639G > A polymorphism was determined in 145 consecutive patients with first ever IS and 145 age- and sex-matched control subjects of Greek Caucasian origin using PCR-RFLP. Stroke severity and functional outcome were assessed on admission and at one month after stroke, respectively. Frequency of VKORC1 −1639G > A genotypes did not differ between IS patients and controls (OR = 1.12, P = 0.51). Moreover, carriage of the A allele was not associated with age of stroke onset, severity of disease (Scandinavian stroke scale score 32.2 versus 32.9, resp., P = 0.96), or poor outcome at 1 month post-stroke (52.9 versus 64.4%, resp., P = 0.31). In conclusion, VKORC1 −1639G > A polymorphism is not a genetic determinant of IS occurrence, age of onset, severity, or functional outcome of disease in a Greek population.

Effect of NQO1 and CYP4F2 genotypes on warfarin dose requirements in Hispanic-Americans and African-Americans

AIM

The objective of this study was to determine the additional contribution of NQO1 and CYP4F2 genotypes to warfarin dose requirements across two racial groups after accounting for known clinical and genetic predictors.

PATIENTS & METHODS

The following were assessed in a cohort of 260 African-Americans and 53 Hispanic-Americans: clinical data; NQO1 p.P187S (*1/*2); CYP2C9*2, *3, *5, *6, *8 and *11; CYP4F2 p.V433M; and VKORC1 c.-1639G>A genotypes.

RESULTS

Both the CYP4F2 433M (0.23 vs 0.06; p < 0.05) and NQO1*2 (0.27 vs 0.18; p < 0.05) allele frequencies were higher in Hispanic-Americans compared with African-Americans. Multiple regression analysis in the Hispanic-American cohort revealed that each CYP4F2 433M allele was associated with a 22% increase in warfarin maintenance dose (p = 0.019). Possession of the NQO1*2 allele was associated with a 34% increase in warfarin maintenance dose (p = 0.004), while adjusting for associated genetic (CYP2C9, CYP4F2 and VKORC1) and clinical factors. In this population, the inclusion of CYP4F2 and NQO1*2 genotypes improved the dose variability explained by the model from 0.58 to 0.68 (p = 0.001), a 17% relative improvement. By contrast, there was no association between CYP4F2 or NQO1*2 genotype and therapeutic warfarin dose in African-Americans after adjusting for known genetic and clinical predictors.

CONCLUSION

In our cohort of inner-city Hispanic-Americans, the CYP4F2 and NQO1*2 genotypes significantly contributed to warfarin dose requirements. If our findings are confirmed, they would suggest that inclusion of the CYP4F2 and NQO1*2 genotypes in warfarin dose prediction algorithms may improve the predictive ability of such algorithms in Hispanic-Americans.

4-hydroxybenzyl alcohol ameliorates cerebral injury in rats by antioxidant action

4-hydroxybenzyl alcohol (4-HBA), one of the phenolic constituents found in many herbal medicinal plants, exhibits beneficial effects in neurological disorders. In the present study, we evaluated 4-HBA's role in transient cerebral ischemia and its potential mechanism. Pre-treatment with 4-HBA (50,100 mg/kg) significantly reduced the cerebral infarct size and improved the neurological symptoms. Morphological examinations showed 4-HBA reduced the number of degenerated neurons. Oxidative stress was evaluated superoxide dismutase (SOD) activity and malondialdehyde (MDA) level. Anti-oxidative mechanisms were studied by Immunofluorescence staining and western immunoblot analysis. 4-HBA increased the expression of NAD(P)H: quinone oxidoreductase1 (NQO1) and ultimately inhibited oxidative stress. In addition, we evaluated the time course expression of NQO1, which was upregulated in the ischemic brain beginning at 1 h. Taken together, these results suggested that 4-HBA ameliorated cerebral injury in rats, This neuroprotective effect is likely related to its antioxidant activities.