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Review
. 2019 Aug 1;26(8):688-696.
doi: 10.5551/jat.RV17035. Epub 2019 Jul 2.

Bilirubin and Endothelial Function

Tatsuya Maruhashi  1 , Yasuki Kihara  1 , Yukihito Higashi  2   3
Affiliations
Review

Bilirubin and Endothelial Function

Tatsuya Maruhashi et al. J Atheroscler Thromb. .

Abstract

Bilirubin is a fundamental metabolic end product of heme degradation. Despite acting as a cytotoxic metabolite at high concentrations, bilirubin at physiological concentrations has antioxidant effects, such as scavenging reactive oxygen species, leading to a decrease in oxidative stress. Endothelial dysfunction is an early feature of and plays an important role in the development and progression of atherosclerosis, leading to cardiovascular complications. One mechanism of endothelial dysfunction is an increase in oxidative stress, by which the bioavailability of nitric oxide is decreased. Therefore, bilirubin is expected to improve endothelial function, to inhibit the progression of atherosclerosis, and to reduce cardiovascular complications by inactivating oxidative stress through its antioxidant effects. In this review, we will focus on the clinical associations of the antioxidant bilirubin with endothelial function and cardiovascular complications.

Keywords: Antioxidant; Bilirubin; Endothelial function; Gilbert's syndrome; Oxidative stress.

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Conflict of interest statement

None.

Figures

Fig. 1.
Fig. 1.
Measurement of flow-mediated vasodilation (FMD) of the brachial artery Modified from Higashi Y, et al. Int Heart J 2015; 56: 633–638 10).
Fig. 2.
Fig. 2.
Heme degradation pathway HO-1: heme oxygenase-1; CO: carbon monoxide; UGT1A1: UDP-glucuronosyltransferase 1A1. Modified from Higashi Y, et al. Trends Cardiovasc Med 2014; 24: 165–169 17).
Fig. 3.
Fig. 3.
Flow-mediated vasodilation (FMD) of the brachial artery (A), serum malondialdehyde-modified low-density lipoprotein (MDA-LDL) (B), and urinary excretion of 8-hydroxy-2′-deoxyguanosine (8-OHdG) in control subjects and patients with Gilbert's syndrome Modified from Maruhashi T, et al. Circulation 2012; 126: 598–603 40).
See this image and copyright information in PMC

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