1
|
He Y, Zhu J, Xiao F, Luo Q, Wang P, Wang X, He Y, Xiong Z. Association of Different Total Bilirubin Levels with Prognosis of Peritoneal Dialysis-Associated Peritonitis. MEDICINA (KAUNAS, LITHUANIA) 2023; 59:1837. [PMID: 37893555 PMCID: PMC10607946 DOI: 10.3390/medicina59101837] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 09/24/2023] [Accepted: 10/13/2023] [Indexed: 10/29/2023]
Abstract
Background and Objectives: Peritoneal dialysis-associated peritonitis (PDAP) poses significant challenges in peritoneal dialysis (PD) patient management and outcomes. Total bilirubin has gained attention due to its antioxidant and immunomodulatory properties. However, its relationship with PDAP prognosis remains underexplored. Materials and Methods: We conducted a retrospective single-center study involving 243 PDAP patients stratified into tertile-based groups according to total bilirubin levels. The association between total bilirubin levels and treatment failure risk was investigated through statistical analyses and restricted cubic spline curve analysis. Results: Our analysis revealed a non-linear correlation between total bilirubin levels and PDAP treatment failure risk. At total bilirubin levels below 8.24 µmol/L, a protective effect was observed, while levels exceeding this threshold heightened the risk of treatment failure. Conclusions: This study unveils a dual role of total bilirubin in PDAP prognosis. Below a certain threshold, it confers protection, while higher levels exacerbate the risk of treatment failure. These findings emphasize the need for further investigation in larger, multicenter prospective studies to validate and elucidate the mechanisms behind bilirubin's impact on PDAP, potentially guiding the development of targeted therapeutic strategies.
Collapse
Affiliation(s)
- Yujian He
- Renal Division, Peking University Shenzhen Hospital, Lianhua Road 1120, Shenzhen 518036, China; (Y.H.); (J.Z.); (F.X.); (Q.L.); (P.W.); (X.W.); (Y.H.)
- PKU-Shenzhen Clinical Institute of Shantou University Medical College, Lianhua Road 1120, Shenzhen 518036, China
| | - Jingjing Zhu
- Renal Division, Peking University Shenzhen Hospital, Lianhua Road 1120, Shenzhen 518036, China; (Y.H.); (J.Z.); (F.X.); (Q.L.); (P.W.); (X.W.); (Y.H.)
- PKU-Shenzhen Clinical Institute of Shenzhen University Medical College, Lianhua Road 1120, Shenzhen 518036, China
| | - Fei Xiao
- Renal Division, Peking University Shenzhen Hospital, Lianhua Road 1120, Shenzhen 518036, China; (Y.H.); (J.Z.); (F.X.); (Q.L.); (P.W.); (X.W.); (Y.H.)
- PKU-Shenzhen Clinical Institute of Shantou University Medical College, Lianhua Road 1120, Shenzhen 518036, China
| | - Qingyun Luo
- Renal Division, Peking University Shenzhen Hospital, Lianhua Road 1120, Shenzhen 518036, China; (Y.H.); (J.Z.); (F.X.); (Q.L.); (P.W.); (X.W.); (Y.H.)
- PKU-Shenzhen Clinical Institute of Shenzhen University Medical College, Lianhua Road 1120, Shenzhen 518036, China
| | - Pengpeng Wang
- Renal Division, Peking University Shenzhen Hospital, Lianhua Road 1120, Shenzhen 518036, China; (Y.H.); (J.Z.); (F.X.); (Q.L.); (P.W.); (X.W.); (Y.H.)
- PKU-Shenzhen Clinical Institute of Shenzhen University Medical College, Lianhua Road 1120, Shenzhen 518036, China
| | - Xu Wang
- Renal Division, Peking University Shenzhen Hospital, Lianhua Road 1120, Shenzhen 518036, China; (Y.H.); (J.Z.); (F.X.); (Q.L.); (P.W.); (X.W.); (Y.H.)
- PKU-Shenzhen Clinical Institute of Shenzhen University Medical College, Lianhua Road 1120, Shenzhen 518036, China
| | - Yan He
- Renal Division, Peking University Shenzhen Hospital, Lianhua Road 1120, Shenzhen 518036, China; (Y.H.); (J.Z.); (F.X.); (Q.L.); (P.W.); (X.W.); (Y.H.)
| | - Zibo Xiong
- Renal Division, Peking University Shenzhen Hospital, Lianhua Road 1120, Shenzhen 518036, China; (Y.H.); (J.Z.); (F.X.); (Q.L.); (P.W.); (X.W.); (Y.H.)
| |
Collapse
|
2
|
Lamina C, Kronenberg F. The causal association of bilirubin with cardiovascular disease: Are there still any questions? Atherosclerosis 2021; 320:92-94. [PMID: 33541708 DOI: 10.1016/j.atherosclerosis.2021.01.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Revised: 01/19/2021] [Accepted: 01/19/2021] [Indexed: 10/22/2022]
Affiliation(s)
- Claudia Lamina
- Institute of Genetic Epidemiology, Department of Genetics and Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
| | - Florian Kronenberg
- Institute of Genetic Epidemiology, Department of Genetics and Pharmacology, Medical University of Innsbruck, Innsbruck, Austria.
| |
Collapse
|
3
|
Roy S, Banerjee U, Dasgupta A. Protective Role of Bilirubin Against Increase in hsCRP in Different Stages of Hypothyroidism. Indian J Clin Biochem 2015; 31:43-9. [PMID: 26855487 DOI: 10.1007/s12291-015-0495-z] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2015] [Accepted: 03/23/2015] [Indexed: 12/22/2022]
Abstract
In conjunction with thyroxine, bilirubin may play an important role for regulation of hsCRP level and a consequent pro-inflammatory condition in hypothyroidism. In present study we evaluated the dependence of hsCRP changes on total bilirubin (BT) and fT4 level in thirty overt (OH) and thirty subclinical hypothyroidism (SH). Serum BT, hsCRP, thyroxine and TSH were measured in both groups and compared with forty control subjects. Serum values of TSH, hsCRP showed raised (P < 0.001 for both) values with lower levels for fT4 and BT (P < 0.001 and 0.03 respectively) in hypothyroid patients compared to the controls. ANOVA showed significant increments in TSH and hsCRP values with decreases in fT4 among the control, SH and OH groups respectively (P < 0.001). BT values showed decrease in OH group only in comparison to controls (P = 0.04). Regression analysis revealed that hsCRP was negatively dependent on fT4 (β = -0.35, P = 0.002) and serum bilirubin (β = -0.40 and P < 0.001 respectively). Univariate general linear model analysis showed this dependence persisted even when carried out distinctly in SH and OH groups separately (P < 0.001). TSH did not show any significant predictive value on the hsCRP level in either of these two tests. From these analyses we suggest that serum hsCRP is closely integrated to a lowered synthesis of bilirubin and fT4 in hypothyroid patients. Furthermore, this causal relationship is not only limited to overt but also extends to the SH.
Collapse
Affiliation(s)
- Suparna Roy
- Department of Biochemistry, Calcutta National Medical College, 32, Gorachand Road, Kolkata, 700014 India
| | - Ushasi Banerjee
- Department of Biochemistry, Calcutta National Medical College, 32, Gorachand Road, Kolkata, 700014 India
| | - Anindya Dasgupta
- Department of Biochemistry, Calcutta National Medical College, 32, Gorachand Road, Kolkata, 700014 India
| |
Collapse
|
4
|
Zahir F, Rabbani G, Khan RH, Rizvi SJ, Jamal MS, Abuzenadah AM. The pharmacological features of bilirubin: the question of the century. ACTA ACUST UNITED AC 2015. [DOI: 10.1515/cmble-2015-0012] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
AbstractThis review looks at the toxicity and metabolism of bilirubin in terms of its pharmacological potential. Its role has gained importance as more research has revealed the functional significance and interrelationship between the gasotransmitters nitric oxide and carbon monoxide. The biological actions of bilirubin have mostly been characterized in the high micromolar range where toxic effects occur. However, it could also prove to be an important cytoprotector for brain tissue, which is inherently less equipped for antioxidant defense. Plasma bilirubin levels negatively correlate to a number of disease states. Higher levels of bilirubin that are still within the normal range provide a protective effect to the body. The effects on various disorders could be tested using controlled pharmacological upregulation of the molecule with animal models. At nanomolar concentrations, considerable benefits have been obtained when the molecule was delivered pharmacologically under in vitro or in vivo test conditions, particularly in neurodegenerative disorders and after tissue or organ transplantation. The induction of heme oxygenase-1 (HMOX-1) via the activation of nuclear factor erythroid 2-related factor or the use of bile pigments in the harvesting of diseased tissue are novel applications, and like every new therapy, should be used with caution. HMOX-1 is tissue specific, and in exceptional states, such as schizophrenia and specific types of renal disorder, the same therapy may have disastrous effects.
Collapse
|
5
|
Jangi S, Otterbein L, Robson S. The molecular basis for the immunomodulatory activities of unconjugated bilirubin. Int J Biochem Cell Biol 2013; 45:2843-51. [PMID: 24144577 DOI: 10.1016/j.biocel.2013.09.014] [Citation(s) in RCA: 97] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2013] [Revised: 09/24/2013] [Accepted: 09/29/2013] [Indexed: 01/03/2023]
Abstract
Nearly a century ago, jaundiced patients were observed to have surprising and spontaneous remissions from incurable immunologic diseases including rheumatoid arthritis, allergy, and asthma. The mystery of why this phenomenon occurred remains unresolved to this day. Bilirubin has traditionally been considered an excretory product resulting from heme metabolism with little benefit to human physiology. In the past few decades, however, the salutary role of this byproduct as a potent antioxidant has been repeatedly noted. Most recently, the molecule has been found to possess immunomodulatory properties that rival its redox capacity, possibly explaining its ability to suppress inflammation. In this review, we specifically examine unconjugated bilirubin (UCB) as an immunomodulator and explore the molecular basis for its immunosuppressive effects.
Collapse
Affiliation(s)
- Sushrut Jangi
- Beth Israel Deaconess Medical Center, United States; Harvard Medical School, United States.
| | | | | |
Collapse
|
6
|
Yu K, Kim C, Sung E, Shin H, Lee H. Association of Serum Total Bilirubin with Serum High Sensitivity C-reactive Protein in Middle-aged Men. Korean J Fam Med 2011; 32:327-33. [PMID: 22745870 PMCID: PMC3383147 DOI: 10.4082/kjfm.2011.32.6.327] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2009] [Accepted: 08/18/2011] [Indexed: 11/22/2022] Open
Abstract
Background It has been suggested that bilirubin has an inverse association with cardiovascular disease (CVD) due to its antioxidant properties. However, there are few data regarding the relationship between serum total bilirubin (sTB) and risk factors for CVD in Koreans. This study aimed to evaluate the relationship between sTB and high sensitivity C-reactive protein (hsCRP), which is an independent risk factor for CVD. Methods We performed a cross sectional study in 6,800 men who were examined at a health promotion center at a university hospital in Korea between May 2005 and June 2006. We grouped the subjects according to values of serum hsCRP (above or below 1.0 mg/L) and compared the characteristics of the two groups. To evaluate the relationship between sTB and hsCRP, we classified the subjects according to quartile values of sTB. Multivariate logistic regression analyses were used to analyze the relationship of levels of sTB and hsCRP after adjusting for known risk factors for CVD. Results Serum hsCRP was significantly associated with body mass index (BMI), smoking, diabetes, hypertension, fasting plasma glucose, systolic blood pressure, alanine aminotransferase, and total cholesterol/high density lipoprotein (TC/HDL-C) ratio, but not with age or alcohol use. As levels of sTB increased, there was a decrease in age, numbers of smokers, BMI, and TC/HDL ratio. Compared to the lowest quartile of sTB, levels of hsCRP decreased with odds ratios of 0.82 (95% CI, 0.71 to 0.96), 0.75 (95% CI, 0.65 to 0.88), and 0.63 (95% CI, 0.54 to 0.74) in the 2nd, 3rd, and 4th quartiles of bilirubin, respectively. Conclusion Bilirubin may be inversely associated with hsCRP
Collapse
Affiliation(s)
- Kiwoong Yu
- Department of Family Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul, Korea
| | | | | | | | | |
Collapse
|
7
|
de Sauvage Nolting PRW, Kusters DM, Hutten BA, Kastelein JJP. Serum bilirubin levels in familial hypercholesterolemia: a new risk marker for cardiovascular disease? J Lipid Res 2011; 52:1755-9. [PMID: 21700833 DOI: 10.1194/jlr.p013193] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Low concentrations of bilirubin are associated with an increased risk for cardiovascular disease (CVD). Possibly, bilirubin exerts its effect through the protection of LDL from oxidation. Therefore, we examined whether low bilirubin might also be a risk marker for CVD in patients with familial hypercholesterolemia (FH) and whether statins influence serum bilirubin levels. Patients with FH were recruited from 37 lipid clinics. After a washout period of 6 weeks, all patients were started on monotherapy with simvastatin 80 mg for a period of two years. A total of 514 patients were enrolled. Bilirubin at baseline was inversely associated with the presence of CVD, also after adjustment for age, gender, presence of hypertension, and HDL cholesterol levels. Moreover, bilirubin levels were significantly raised, by 7%, from 10.0 to 10.8 μmol/L after treatment with simvastatin 80 mg. We hypothesize first that high bilirubin levels might protect patients with FH from CVD. Furthermore, bilirubin levels were significantly increased after treatment with simvastatin 80 mg, independent of changes in liver enzymes, which might confer additional protection against CVD. Whether this is also true for lower doses of simvastatin or for other statins remains to be investigated.
Collapse
|
8
|
Ohnaka K, Kono S. Bilirubin, cardiovascular diseases and cancer: epidemiological perspectives. Expert Rev Endocrinol Metab 2010; 5:891-904. [PMID: 30780834 DOI: 10.1586/eem.10.65] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
Owing to a potent antioxidant property of bilirubin, a growing interest has been drawn to the potential protective effects of bilirubin against oxidative stress-related diseases. This article evaluates associations of bilirubin with atherosclerotic diseases and cancer. Serum bilirubin has consistently been shown to be inversely associated with diverse atherosclerotic diseases, mostly among men in different populations. A limited number of prospective studies have shown a U-shaped or reversed J-shaped relationship between bilirubin and coronary heart disease in men and no evident association in women. Few studies have provided evidence supportive of a protective association between bilirubin and cancer risk. The findings on bilirubin-related genetic polymorphisms are inconsistent in relation to coronary heart disease and cancer.
Collapse
Affiliation(s)
- Keizo Ohnaka
- a Graduate School of Medical Sciences, Kyushu University, Higashi-ku, Fukuoka 812-8582, Japan
| | - Suminori Kono
- a Graduate School of Medical Sciences, Kyushu University, Higashi-ku, Fukuoka 812-8582, Japan
- b
| |
Collapse
|
9
|
Lin JP, Vitek L, Schwertner HA. Serum bilirubin and genes controlling bilirubin concentrations as biomarkers for cardiovascular disease. Clin Chem 2010; 56:1535-43. [PMID: 20693308 DOI: 10.1373/clinchem.2010.151043] [Citation(s) in RCA: 112] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Abstract
BACKGROUND Serum bilirubin has been consistently shown to be inversely related to cardiovascular disease (CVD). Recent studies showed serum bilirubin to be associated with CVD-related factors such as diabetes, metabolic syndrome, and body mass index. Although the association of serum bilirubin with CVD has been found in both retrospective and prospective studies, less information is available on the role of genes that control bilirubin concentrations and their association with CVD. CONTENT In this review, we provide detailed information on the identity of the major genes that control bilirubin concentrations and their association with serum bilirubin concentrations and CVD risk. We also update the results of the major studies that have been performed on the association between serum bilirubin, CVD, and CVD-related diseases such as diabetes or metabolic syndrome. Studies consistently indicate that bilirubin concentrations are inversely associated with different types of CVD and CVD-related diseases. A conditional linkage study indicates that UGT1A1 is the major gene controlling serum bilirubin concentrations, and this finding has been confirmed in recent genomewide association studies. Studies also indicate that individuals homozygous for UGT1A1*28 have a significantly lower risk of developing CVD than carriers of the wild-type alleles. SUMMARY Serum bilirubin has a protective effect on CVD and CVD-related diseases, and UGT1A1 is the major gene controlling serum bilirubin concentrations. Pharmacologic, nonpharmacologic, or genetic interventions that increase serum bilirubin concentrations could provide more direct evidence on the role of bilirubin in CVD prevention.
Collapse
Affiliation(s)
- Jing-Ping Lin
- Office of Biostatistics Research, Division of Cardiovascular Science, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD, USA
| | | | | |
Collapse
|
10
|
Abstract
The potential for genetic variation to modulate neonatal hyperbilirubinemia risk is increasingly being recognized. In particular, polymorphisms across three genes involved in bilirubin production and metabolism [glucose-6-phosphate dehydrogenase (G6PD), uridine diphosphate glucuronosyl transferase 1A1 (UGT1A1), and solute carrier organic anion transporter polypeptide 1B1 (SLCO1B1)] may interact with each other and/or environmental contributors to produce significant hyperbilirubinemia. Variant gene co-expression including compound and synergistic heterozygosity enhances hyperbilirubinemia risk, contributing to the etiologic heterogeneity and complex nature of neonatal jaundice.
Collapse
Affiliation(s)
- Jon F Watchko
- Division of Newborn Medicine, Department of Pediatrics, Magee-Women's Hospital, University of Pittsburgh School of Medicine, Pittsburgh, PA 15213, USA.
| | | |
Collapse
|
11
|
Vera T, Granger JP, Stec DE. Inhibition of bilirubin metabolism induces moderate hyperbilirubinemia and attenuates ANG II-dependent hypertension in mice. Am J Physiol Regul Integr Comp Physiol 2009; 297:R738-43. [PMID: 19571206 DOI: 10.1152/ajpregu.90889.2008] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Population studies indicate that moderate hyperbilirubinemia is associated with reduced incidence of cardiovascular diseases, including hypertension. Despite this correlative evidence, no studies have directly tested the hypothesis that moderate increases in plasma bilirubin levels can attenuate the development of hypertension. This hypothesis was tested by treating mice with Indinavir, a drug that competes with bilirubin for metabolism by UDP-glucuronosyltransferase 1A1 (UGT1A1). Treatment of mice with Indinavir (500 mg x kg(-1) x day(-1), gavage) resulted in a twofold increase in plasma unconjugated bilirubin levels. Next, we determined the effect of Indinavir-induced changes in plasma bilirubin on the development of ANG II-dependent hypertension. Moderate hyperbilirubinemia was induced 3 days before the implantation of an osmotic minipump that delivered ANG II at a rate of 1 microg x kg(-1) x min(-1). ANG II infusion increased mean arterial pressure (MAP) by 20 mmHg in control mice but by only 6 mmHg in mice treated with Indinavir (n = 6). Similar to Indinavir treatment, direct infusion of bilirubin (37.2 mg x kg(-1) x day(-1) i.v.) resulted in a twofold increase in plasma bilirubin levels and also attenuated the development of ANG II-dependent hypertension. Moderate hyperbilirubinemia resulted in an increase in plasma nitrate/nitrite levels, which averaged 36 +/- 2 vs. 50 +/- 7 microM in ANG II vehicle vs. Indinavir-treated mice (n = 5). Moderate hyperbilirubinemia resulted in attenuation of vascular oxidative stress as determined by dihydroethidium staining of aortic segments. These results indicate that moderate hyperbilirubinemia prevents ANG II-dependent hypertension by a mechanism that may involve decreases in vascular oxidative stress.
Collapse
Affiliation(s)
- Trinity Vera
- Dept. of Physiology and Biophysics, University of Mississippi Medical Center, Jackson, Mississippi 39216-4505, USA.
| | | | | |
Collapse
|
12
|
Lin R, Wang X, Wang Y, Zhang F, Wang Y, Fu W, Yu T, Li S, Xiong M, Huang W, Jin L. Association of polymorphisms in four bilirubin metabolism genes with serum bilirubin in three Asian populations. Hum Mutat 2009; 30:609-15. [DOI: 10.1002/humu.20895] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
|
13
|
Conditional linkage and genome-wide association studies identify UGT1A1 as a major gene for anti-atherogenic serum bilirubin levels--the Framingham Heart Study. Atherosclerosis 2009; 206:228-33. [PMID: 19389676 DOI: 10.1016/j.atherosclerosis.2009.02.039] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/08/2009] [Revised: 02/06/2009] [Accepted: 02/22/2009] [Indexed: 02/08/2023]
Abstract
OBJECTIVE AND METHODS Low bilirubin levels are significantly associated with cardiovascular diseases (CVD). In previous genome-wide linkage studies we identified a major locus on chromosome 2q harboring the candidate gene UDP-glucuronosyltransferase (UGT1A1). The activity of this enzyme is significantly influenced by a TA-repeat polymorphism in the promoter of the gene. In a prospective study individuals with genotype (TA)7/(TA)7 had significantly higher bilirubin levels and approximately one-third the risk of CVD as carriers of the wildtype (TA)6 allele. In the present study we performed a conditional linkage study to investigate whether this polymorphism explains the observed linkage peak and extended our analysis by a genome-wide association study on bilirubin levels in 1345 individuals. RESULTS After adjustment for the bilirubin variance explained by this polymorphism, the LOD score on chromosome 2q dropped from 3.8 to 0.4, demonstrating that this polymorphism explains the previous linkage result. For the genome-wide association study, the closest marker to UGT1A1 was in the top ranking SNPs. The association became even stronger when we considered the TA-repeat polymorphism in the analysis (p=2.68 x 10(-53)). Five other SNPs in other regions reached genome-wide significance without obvious connection to bilirubin metabolism. CONCLUSIONS Our studies suggest that UGT1A1 may be the major gene with strong effects on bilirubin levels and the TA-repeat polymorphism might be the key polymorphism within the gene controlling bilirubin levels. Since this polymorphism has a high frequency and a substantial impact on the development of CVD, the gene might be an important drug target.
Collapse
|
14
|
Serum bilirubin levels, UGT1A1 polymorphisms and risk for coronary artery disease. Exp Gerontol 2008; 43:1102-7. [PMID: 18790042 DOI: 10.1016/j.exger.2008.08.047] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2008] [Revised: 08/12/2008] [Accepted: 08/19/2008] [Indexed: 12/11/2022]
Abstract
Low levels of the antioxidative serum bilirubin are associated with vascular aging and an increased risk for coronary artery disease (CAD). UGT1A1 is the major gene influencing bilirubin concentrations. Therefore, we investigated an association of bilirubin levels and two polymorphisms in the promoter of UGT1A1 (-53(TA-repeat) polymorphism and T-3279G) in 477 patients with premature, familial CAD and 619 age- and sex-matched controls. Bilirubin concentrations were significantly lower in cases than in controls (0.62+/-0.36 vs. 0.76+/-0.41 mg/dl for men, p=1.2 x 10(-10); and 0.42+/-0.29 vs. 0.55+/-0.23 mg/dl, p=1.9 x 10(-9) for women). Both polymorphisms showed a strong association with bilirubin levels with higher levels for homozygote carriers of the minor allele. These associations were most pronounced in male controls and patients (p=5.9 x 10(-26) and p=3.4 x 10(-16), respectively, for the -53(TA-repeat) polymorphism). Logistic regression analysis revealed low bilirubin levels but not the UGT1A1 polymorphisms to be significantly associated with CAD: OR (95% CI) 0.90 (0.86-0.94), p=2.6 x 10(-6) for men and 0.77 (0.68-0.87), p=3.2 x 10(-5) for women, respectively for each 0.1mg/dl increase of bilirubin. These results indicate that it is rather decreased bilirubin levels in general than the changes in the genetic variation of this gene that increase the risk for CAD.
Collapse
|
15
|
Schwertner HA, Vítek L. Gilbert syndrome, UGT1A1*28 allele, and cardiovascular disease risk: possible protective effects and therapeutic applications of bilirubin. Atherosclerosis 2008; 198:1-11. [PMID: 18343383 DOI: 10.1016/j.atherosclerosis.2008.01.001] [Citation(s) in RCA: 169] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/13/2007] [Revised: 11/08/2007] [Accepted: 01/11/2008] [Indexed: 02/06/2023]
Abstract
Serum bilirubin has been shown to be inversely related to cardiovascular disease (CVD) in both retrospective and prospective studies. Meta-analysis of existing studies has also confirmed that serum bilirubin concentrations are inversely related to CVD. Less information is known about the protective effects of slightly elevated serum bilirubin concentrations. In this review, we will focus primarily on the association of serum bilirubin and CVD and the possible protective roles of bilirubin, heme oxygenase (HO), and bilirubin UDP-glucuronosyltransferase (UGT1A1). HO and biliverdin reductase control the formation of bilirubin, whereas UGT1A1 controls bilirubin conjugation and clearance. Because of the health and therapeutic implications of slightly elevated serum bilirubin concentrations, we will discuss the recent prospective studies on cardiovascular risk in individuals with Gilbert syndrome (GS) as well as those with the UGT1A1*28 allele. Such individuals have decreased hepatic bilirubin UDP-glucuronosyltransferase activity, decreased bilirubin clearance, and increased serum bilirubin concentrations. Lastly, we will discuss some of the therapeutic approaches that could be used to increase serum bilirubin concentrations to prevent CVD and other oxidative and inflammatory diseases.
Collapse
|
16
|
Moon JS, Chang WJ, Lee CH, Lee JE, Chun KA, Yoon JS, Cho IH, Lee HW, Won KC. Relationship Between Serum Bilirubin Levels and Coronary Atherosclerosis in Patients with Type 2 Diabetes. KOREAN DIABETES JOURNAL 2008. [DOI: 10.4093/kdj.2008.32.4.338] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Jun Sung Moon
- Department of Internal Medicine, College of Medicine, Yeungnam University, Korea
| | - Woo Jin Chang
- Department of Internal Medicine, College of Medicine, Yeungnam University, Korea
| | - Chan Hee Lee
- Department of Internal Medicine, College of Medicine, Yeungnam University, Korea
| | - Ji Eun Lee
- Department of Internal Medicine, College of Medicine, Yeungnam University, Korea
| | - Kyung Ah Chun
- Department of Nuclear Medicine, College of Medicine, Yeungnam University, Korea
| | - Ji Sung Yoon
- Department of Internal Medicine, College of Medicine, Yeungnam University, Korea
| | - Ihn Ho Cho
- Department of Nuclear Medicine, College of Medicine, Yeungnam University, Korea
| | - Hyoung Woo Lee
- Department of Internal Medicine, College of Medicine, Yeungnam University, Korea
| | - Kyu Chang Won
- Department of Internal Medicine, College of Medicine, Yeungnam University, Korea
| |
Collapse
|
17
|
Troughton JA, Woodside JV, Young IS, Arveiler D, Amouyel P, Ferrières J, Ducimetière P, Patterson CC, Kee F, Yarnell JWG, Evans A. Bilirubin and coronary heart disease risk in the Prospective Epidemiological Study of Myocardial Infarction (PRIME). ACTA ACUST UNITED AC 2007; 14:79-84. [PMID: 17301631 DOI: 10.1097/01.hjr.0000230097.81202.9f] [Citation(s) in RCA: 79] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
BACKGROUND Classic coronary heart disease risk factors fail to explain the large coronary heart disease incidence gradient between Northern Ireland and France. The Prospective Epidemiological Study of Myocardial Infarction (PRIME), a multicentre prospective study of 10593 men, aims to investigate novel risk factors in these populations. We tested the hypothesis that higher bilirubin, a bile pigment possessing antioxidant properties, is associated with decreased coronary heart disease risk. METHODS Bilirubin was measured in 216 participants who had developed coronary heart disease at 5-year follow-up and in 434 matched controls. RESULTS Bilirubin was significantly lower in cases (geometric mean 7.95 micromol/l; interquartile range 5.32-12.33 micromol/l) compared with controls (9.07; 6.16-12.76; P=0.005). Conditional logistic regression, adjusted for classical and putative risk factors, showed a U-shaped pattern, with coronary heart disease risk significantly lower for bilirubin in the third and fourth fifths, compared with the first. Additionally, there was a significant quadratic relationship between coronary heart disease risk and fifths of bilirubin concentration (chi2=6.80, df=2; P=0.035). CONCLUSIONS These findings suggest that bilirubin is a novel coronary heart disease risk marker in middle-aged men, with a U-shaped relationship observed between bilirubin concentration and coronary heart disease risk.
Collapse
|
18
|
Clementi M, Di Gianantonio E, Fabris L, Forabosco P, Strazzabosco M, Tenconi R, Okolicsanyi L. Inheritance of hyperbilirubinemia: evidence for a major autosomal recessive gene. Dig Liver Dis 2007; 39:351-5. [PMID: 17347060 DOI: 10.1016/j.dld.2006.12.019] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/06/2006] [Revised: 12/02/2006] [Accepted: 12/18/2006] [Indexed: 12/11/2022]
Abstract
BACKGROUND AND AIM To clarify the precise mode of inheritance of Gilbert syndrome, an unconjugated familial hyperbilirubinemia, where impaired bilirubin conjugation is caused by reduced UGT1A1 activity determined by a defective function of the A(TA)6TAA promoter region of the UGT1A1 gene. SUBJECTS AND METHODS Serum bilirubin levels were measured in a large, homogeneous resident population from North-Eastern Italy, consisting of 1.639 males (age 44.5+/-13.9, range 18-89 years), and 1.420 females (age 45.1+/-15.0, range 18-85). In 112 nuclear families from hyperbilirubinemic probands living in the same area a complex segregation analysis was then performed. In both samples we carefully excluded potentially confounding factors of bilirubin levels (alcohol abuse, excessive cigarette smoking, drug consumption, overt haemolysis and liver disease). RESULTS Mean serum bilirubin concentrations are higher in males than in females, showing fluctuations through the different age periods in males. Complex segregation results demonstrate that unconjugated hyperbilirubinemia exhibits a precise mode of inheritance in which a major recessive gene with a frequency of 0.45 is responsible for higher serum bilirubin values. CONCLUSIONS This major recessive gene accounts only for a part of the serum bilirubin concentration, thus implying additional, environmental factors for the clinical appearance of GS.
Collapse
Affiliation(s)
- M Clementi
- Clinical Genetics and Epidemiology, Department of Pediatrics, University of Padua, Italy
| | | | | | | | | | | | | |
Collapse
|
19
|
Affiliation(s)
- Thomas W Sedlak
- Department of Neuroscience, Johns Hopkins School of Medicine, Baltimore, Maryland 21205, USA.
| | | |
Collapse
|
20
|
Innocenti F, Undevia SD, Iyer L, Chen PX, Das S, Kocherginsky M, Karrison T, Janisch L, Ramírez J, Rudin CM, Vokes EE, Ratain MJ. Genetic variants in the UDP-glucuronosyltransferase 1A1 gene predict the risk of severe neutropenia of irinotecan. J Clin Oncol 2004; 22:1382-8. [PMID: 15007088 DOI: 10.1200/jco.2004.07.173] [Citation(s) in RCA: 712] [Impact Index Per Article: 35.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
PURPOSE Severe toxicity is commonly observed in cancer patients receiving irinotecan. UDP-glucuronosyltransferase 1A1 (UGT1A1) catalyzes the glucuronidation of the active metabolite SN-38. This study prospectively evaluated the association between the prevalence of severe toxicity and UGT1A1 genetic variation. PATIENTS AND METHODS Sixty-six cancer patients with advanced disease refractory to other treatments received irinotecan 350 mg/m(2) every 3 weeks. Toxicity and pharmacokinetic data were measured during cycle 1. UGT1A1 variants (-3279G>T, -3156G>A, promoter TA indel, 211G>A, 686C>A) were genotyped. RESULTS The prevalence of grade 4 neutropenia was 9.5%. Grade 4 neutropenia was much more common in patients with the TA indel 7/7 genotype (3 of 6 patients; 50%) compared with 6/7 (3 of 24 patients; 12.5%) and 6/6 (0 of 29 patients; 0%) (P =.001). The TA indel genotype was significantly associated with the absolute neutrophil count nadir (7/7 < 6/7 < 6/6, P =.02). The relative risk of grade 4 neutropenia was 9.3 (95% CI, 2.4 to 36.4) for the 7/7 patients versus the rest of the patients. Pretreatment total bilirubin levels (mean +/- standard deviation) were significantly higher in patients with grade 4 neutropenia (0.83 +/- 0.08 mg/dL) compared to those without grade 4 neutropenia (0.47 +/- 0.03 mg/dL; P <.001). The -3156G>A variant seemed to distinguish different phenotypes of total bilirubin within the TA indel genotypes. The -3156 genotype and the SN-38 area under the concentration versus time curve were significant predictors of ln(absolute neutrophil count nadir; r(2) = 0.51). CONCLUSION UGT1A1 genotype and total bilirubin levels are strongly associated with severe neutropenia, and could be used to identify cancer patients predisposed to the severe toxicity of irinotecan. The hypothesis that the -3156G>A variant is a better predictor of UGT1A1 status than the previously reported TA indel requires further testing.
Collapse
Affiliation(s)
- Federico Innocenti
- Department of Medicine, University of Chicago, 5841 S Maryland Ave, MC2115, Chicago, IL 60637, USA
| | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Novotný L, Vítek L. Inverse relationship between serum bilirubin and atherosclerosis in men: a meta-analysis of published studies. Exp Biol Med (Maywood) 2003; 228:568-71. [PMID: 12709588 DOI: 10.1177/15353702-0322805-29] [Citation(s) in RCA: 262] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Bilirubin, a major intravascular product of heme catabolism, is a potent antioxidant compound. Numerous studies have been published showing the relationship between serum bilirubin levels and atherosclerosis. In the present investigation all the epidemiological studies available on the effect of serum bilirubin levels and atherosclerotic disease were analyzed. Studies on the epidemiology of atherosclerotic diseases in relation to serum bilirubin levels were searched in the MEDLINE database. Selected studies were subdivided according to serum bilirubin levels and severity of atherosclerotic disease. Because of the limited number of females involved in the studies, only males were included into meta-analysis. Associations for ordered categorical variables (bilirubin and natural history of graded atherosclerosis) were assessed to find correlation and linear trend between analyzed variables. A stratified analysis was conducted to compare risks of clinical outcomes. Eleven relevant studies were used for analysis. A close negative relationship was found between serum bilirubin levels and severity of atherosclerosis (Spearman rank coefficient r = -0.31,P < 0.0001). The linear trend was confirmed in analysis of proportions with x(2) values for both disease conditions to be very significant (P < 0.0001). Unambiguous inverse relationship between serum bilirubin levels and atherosclerosis was demonstrated in this preliminary meta-analytic study. These results indicate the importance of hem oxygenase-related products in the prevention of oxidative stress-mediated diseases.
Collapse
Affiliation(s)
- Ladislav Novotný
- EuroMISE Center-Cardio and Institute of Hygienic Medicine and Epidemiology, 1st Medical Faculty, Charles University, Prague, Czech Republic
| | | |
Collapse
|
22
|
Lin JP, Cupples LA, Wilson PWF, Heard-Costa N, O'Donnell CJ. Evidence for a gene influencing serum bilirubin on chromosome 2q telomere: a genomewide scan in the Framingham study. Am J Hum Genet 2003; 72:1029-34. [PMID: 12618960 PMCID: PMC1180333 DOI: 10.1086/373964] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2002] [Accepted: 01/07/2003] [Indexed: 11/03/2022] Open
Abstract
There is an inverse relationship between serum bilirubin concentrations and risk of coronary artery disease. The strength of the association is similar to that of smoking, systolic blood pressure, and HDL cholesterol. We carried out a genomewide scan in a Framingham Heart Study. Our study sample consisted of 330 families with 1,394 sibling pairs, 681 cousin pairs, and 89 avuncular pairs. Using variance-component methods, the heritability was estimated to be 49%+/-6%, and the genome scan demonstrated significant evidence of linkage of serum bilirubin to chromosome 2q, with a LOD score of 3.8 at location 243 cM. The peak multipoint LOD score is located 1 cM away from the uridine diphosphate glycosyltransferase 1 (UGT1A1) gene. UGT1A1 catalyzes the conjugation of bilirubin with glucuronic acid and thus enhances bilirubin elimination; therefore, it is an important candidate gene for serum bilirubin. Gilbert syndrome, a hyperbilirubinemic syndrome, has a population frequency of 2%-19% and is mainly due to a TA insertion at the promoter region of UGT1A1. Only one other region in the genome produced a multipoint LOD score >1 (LOD = 1.3). Our findings suggest that UGT1A1 may be a major gene controlling serum bilirubin levels in the population.
Collapse
Affiliation(s)
- Jing-Ping Lin
- Division of Epidemiology and Clinical Applications, National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD 20892, USA.
| | | | | | | | | |
Collapse
|
23
|
Kronenberg F, Coon H, Gutin A, Abkevich V, Samuels ME, Ballinger DG, Hopkins PN, Hunt SC. A genome scan for loci influencing anti-atherogenic serum bilirubin levels. Eur J Hum Genet 2002; 10:539-46. [PMID: 12173031 DOI: 10.1038/sj.ejhg.5200842] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2001] [Revised: 05/14/2002] [Accepted: 05/16/2002] [Indexed: 01/19/2023] Open
Abstract
Epidemiological studies have shown an association of decreased serum bilirubin levels with coronary artery disease. Two segregation analyses in large pedigrees have suggested a major gene responsible for high bilirubin levels occurring in about 12% of the population. Based on a recessive model from a previous segregation analysis, we performed a genome scan using 587 markers genotyped in 862 individuals from 48 Utah pedigrees to detect loci linked to high bilirubin levels. As a complementary approach, non-parametric linkage (NPL) analysis was performed. These two methods identified four regions showing evidence for linkage. The first region is on chromosome 2q34-37 with multipoint LOD and NPL scores of 3.01 and 3.22, respectively, for marker D2S1363. This region contains a previously described gene, uridine diphosphate glycosyltransferase 1, which has been associated with high bilirubin levels. A polymorphism in the promoter of this gene was recently shown to be responsible for Gilbert syndrome which is associated with mild hyperbilirubinemia. The other regions were found on chromosomes 9q21, 10q25-26, and 18q12 with maximum NPL scores of 2.39, 1.55, and 2.79, respectively. Furthermore, we investigated in these pedigrees the association between bilirubin levels and coronary artery disease. One-hundred and sixty-one male and 41 female subjects had already suffered a coronary artery disease event. Male patients showed significantly lower bilirubin concentrations than age-matched controls. This association, however, was not observed in females. These results provide evidence that loci influencing bilirubin variation exist on chromosomes 2q34-37, 9q21, 10q25-26, and 18q12 and confirms the association of low bilirubin levels with coronary artery disease in males.
Collapse
|
24
|
Hunt SC, Kronenberg F, Eckfeldt JH, Hopkins PN, Myers RH, Heiss G. Association of plasma bilirubin with coronary heart disease and segregation of bilirubin as a major gene trait: the NHLBI family heart study. Atherosclerosis 2001; 154:747-54. [PMID: 11257278 DOI: 10.1016/s0021-9150(00)00420-2] [Citation(s) in RCA: 72] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Decreased serum bilirubin levels have been associated with coronary heart disease (CHD). It is believed that bilirubin acts as an antioxidant, preventing formation of oxidized LDL and subsequent atherosclerosis. Serum bilirubin also segregates as a major gene, with the rarer genotype associated with elevated bilirubin levels and occurring in about 12% of the population. Using a large population-based study of random and CHD high risk families, this analysis was designed to replicate the association of lower serum bilirubin levels with early CHD (onset by age 55 for males and 65 for females) using 328 case/control samples and the major gene segregation of bilirubin levels in 555 families. There were significant differences in plasma bilirubin levels between 188 males (12.5 micromol/l) and 140 females (9.3 micromol/l, P<0.0001). Higher serum albumin and lower HDL-C significantly correlated with higher plasma bilirubin levels in females but not males. In sex-specific logistic regression models of early CHD (148 cases and 180 controls), lower plasma bilirubin was associated with increased prevalence of CHD in males with borderline significance (odds ratio=0.93 for a 1 micromol/l increase in bilirubin, P=0.056) but not in females. Bilirubin was found to segregate as a major gene using all 555 families consisting of 1292 individuals, with estimates replicating those in the previously published study. The most parsimonious model was a recessive model for high bilirubin levels that occurred in about 23% of the population. The means were separated by 1.7 standard deviations and there was a significant polygenic effect (h2=0.33, P=0.0009). We conclude that decreased bilirubin is mildly related to CHD in males but not in females. Because of an inverse correlation between HDL-C and bilirubin, the protective high HDL-C levels may have counteracted the CHD risk associated with lower bilirubin levels in females. The inferred major gene for bilirubin may protect against CHD, since elevated levels, rather than lower levels, were associated with this inferred gene.
Collapse
Affiliation(s)
- S C Hunt
- Department of Cardiovascular Genetics, University of Utah School of Medicine, Salt Lake City, UT 84108, USA.
| | | | | | | | | | | |
Collapse
|
25
|
Abstract
AbstractBackground: Lipid oxidation and formation of oxygen radicals are important elements of arterial plaque formation and atherosclerosis, and are involved in the pathophysiology of coronary artery disease (CAD). Because bilirubin has antioxidant properties, it has been suggested that it may have a protective role in the atherosclerotic process.Approach: This review examines in vitro and in vivo studies indicating that bilirubin inhibits lipid oxidation and oxygen radical formation. Experimental and epidemiological evidence is presented that suggests that bilirubin may serve as a physiological antioxidant providing protection against atherosclerosis and CAD. Special attention is focused on studies that noted an inverse relationship between plasma bilirubin concentration and cardiovascular morbidity.Content: Serum bilirubin concentrations in the upper portion of the reference interval reportedly reduce atherogenic risk and provide protection against CAD. In contrast, serum bilirubin concentrations in the lower portion of the reference interval may be associated with increased risk of ischemic heart disease.Summary: Taken together, the evidence presented in this review supports the concept that bilirubin, via its antioxidant potential, has antiatherogenic properties and that an inverse relationship exists between circulating bilirubin concentrations and risk of CAD.
Collapse
Affiliation(s)
- Michael Mayer
- Department of Laboratory Medicine, University of Washington Medical Center, Seattle, WA 98103-7110
| |
Collapse
|
26
|
Cunningham O, Dunne A, Sabido P, Lightner D, Mantle TJ. Studies on the specificity of the tetrapyrrole substrate for human biliverdin-IXalpha reductase and biliverdin-IXbeta reductase. Structure-activity relationships define models for both active sites. J Biol Chem 2000; 275:19009-17. [PMID: 10858451 DOI: 10.1074/jbc.275.25.19009] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
A comparison of the initial rate kinetics for human biliverdin-IXalpha reductase and biliverdin-IXbeta reductase with a series of synthetic biliverdins with propionate side chains "moving" from a bridging position across the central methene bridge (alpha isomers) to a "gamma-configuration" reveals characteristic behavior that allows us to propose distinct models for the two active sites. For human biliverdin-IXalpha reductase, as previously discussed for the rat and ox enzymes, it appears that at least one "bridging propionate" is necessary for optimal binding and catalytic activity, whereas two are preferred. All other configurations studied were substrates for human biliverdin-IXalpha reductase, albeit poor ones. In the case of mesobiliverdin-XIIIalpha, extending the propionate side chains to hexanoate resulted in a significant loss of activity, whereas the butyrate derivative retained high activity. For human biliverdin-IXalpha reductase, we suggest that a pair of positively charged side chains play a key role in optimally binding the IXalpha isomers. In the case of human biliverdin-IXbeta reductase, the enzyme cannot tolerate even one propionate in the bridging position, suggesting that two negatively charged residues on the enzyme surface may preclude productive binding in this case. The flavin reductase activity of biliverdin-IXbeta reductase is potently inhibited by mesobiliverdin-XIIIalpha and protohemin, which is consistent with the hypothesis that the tetrapyrrole and flavin substrate bind at a common site.
Collapse
Affiliation(s)
- O Cunningham
- Department of Biochemistry, Trinity College, Dublin 2, Ireland and the Departments of Chemistry & Biochemistry, University of Nevada, Reno, Nevada 89557-0020, USA
| | | | | | | | | |
Collapse
|
27
|
Ennis O, Maytum R, Mantle TJ. Cloning and overexpression of rat kidney biliverdin IX alpha reductase as a fusion protein with glutathione S-transferase: stereochemistry of NADH oxidation and evidence that the presence of the glutathione S-transferase domain does not effect BVR-A activity. Biochem J 1997; 328 ( Pt 1):33-6. [PMID: 9359830 PMCID: PMC1218883 DOI: 10.1042/bj3280033] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Native biliverdin IX alpha reductase (BVR-A) is a monomer of molecular mass 34 kDa. We have developed an expression vector that allows the isolation of 40 mg of a glutathione S-transferase (GST)-BVR-A fusion protein from 1 litre of culture. The fusion protein (60 kDa) behaves as a dimer on gel filtration (120 kDa), so that we have artificially created a BVR-A dimer. The recombinant rat kidney enzyme exhibits pre-steady-state 'burst' kinetics that show a pH dependence similar to that already described for ox kidney BVR-A. Similar behaviour was obtained in the presence and absence of the GST domain both for the burst kinetics and during initial-rate studies in the presence and absence of albumin. The stereospecificity of the BVR-A-catalysed oxidation of [4-3H]NADH, labelled at the A and B faces, was shown to occur exclusively via the B face.
Collapse
Affiliation(s)
- O Ennis
- Department of Biochemistry, Trinity College, Dublin, Ireland
| | | | | |
Collapse
|
28
|
Madhavan M, Wattigney WA, Srinivasan SR, Berenson GS. Serum bilirubin distribution and its relation to cardiovascular risk in children and young adults. Atherosclerosis 1997; 131:107-13. [PMID: 9180251 DOI: 10.1016/s0021-9150(97)06088-7] [Citation(s) in RCA: 80] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
There is evidence that bilirubin functions as an endogenous tissue protector by its antioxidant and anti-complement actions, properties that are relevant to atherogenesis. Serum bilirubin distribution and its relation to cardiovascular risk were examined in 4156 individuals aged 5-30 years from a biracial (black white) community. Bilirubin levels showed significant differences related to race (whites > blacks) and sex (males > females, except in 5-10 year olds). In males the levels increased with age up to 24 years, while in females the changes were less conspicuous. Both adiposity and cigarette smoking associated independently and inversely with bilirubin. In addition, serum bilirubin correlated positively with HDL cholesterol and inversely with triglycerides, VLDL cholesterol, LDL cholesterol, insulin, glucose and systolic blood pressure although these correlations were significant only in certain age-race-sex groups. Offspring with a parental history of heart attack or hypertension had consistently lower bilirubin levels than those without such parental history. Thus, bilirubin may be an inverse risk factor for cardiovascular disease.
Collapse
Affiliation(s)
- M Madhavan
- Department of Pathology, University of Madras, Postgraduate Institute of Basic Medical Sciences, India
| | | | | | | |
Collapse
|