Serum Bilirubin Concentration is Associated with Left Ventricular Remodeling in Patients with Type 2 Diabetes Mellitus: A Cohort Study

Protective and curative effects of unconjugated bilirubin on gene expression of LOX-1 and iNOS in the heart of rats receiving high-fat diet and low dose streptozotocin: a histomorphometric approach

BACKGROUND

Atherosclerosis is a chronic inflammatory condition affecting the large arteries and is a major cause of cardiovascular diseases (CVDs) globally. Increased levels of adhesion molecules in cardiac tissue serve as prognostic markers for coronary artery occlusion risk. Given the antioxidant properties of bilirubin and its inverse correlation with atherosclerosis, this study aimed to assess the beneficial effects of bilirubin on atherosclerotic indices and heart structure in high-fat diet-fed diabetic rats with atherosclerosis.

METHODS

Atherosclerosis was induced in three out of five groups of adult male Sprague Dawley rats through a 14-week period of high-fat diet (HFD) consumption and a single low dose of streptozotocin (STZ) (35 mg/kg). The atherosclerotic rats were then treated with intraperitoneal administration of 10 mg/kg/day bilirubin for either 6 or 14 weeks (treated and protected groups, respectively), or the vehicle. Two additional groups served as the control and bilirubin-treated rats. Subsequently, the mRNA expression levels of vascular cell adhesion molecule 1 (VCAM-1), intercellular adhesion molecule 1 (ICAM-1), lectin-like LDL receptor 1 (LOX-1), and the inducible nitric oxide synthase (iNOS) were analyzed using quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR). Histopathological and stereological analyses were performed to assess changes in the heart structure.

RESULTS

Bilirubin significantly decreased the expression of VCAM-1, ICAM-1, LOX-1, and iNOS genes in the treated group. Moreover, bilirubin mitigated pathological damage in the left ventricle of the heart. Stereological analysis revealed a decrease in the left ventricle and myocardium volume, accompanied by an increase in vessel volume in rats treated with bilirubin.

CONCLUSION

These findings demonstrate that mild hyperbilirubinemia can protect against the progression of atherosclerosis and heart failure by improving lipid profile, modulating adhesion molecules, LOX-1, and iNOS gene expression levels.

Aggravating effect of obstructive sleep apnoea on left ventricular remodelling and function disorder in patients with type 2 diabetes mellitus: a case-control study by 3D speckle tracking echocardiography

OBJECTIVES

The purpose of this study was to evaluate the early alterations of left ventricular (LV) structure and function in type 2 diabetes mellitus (T2DM) patients with or without obstructive sleep apnoea (OSA) using 3 D speckle tracking echocardiography (3DSTE).

METHODS

Eighty T2DM patients with preserved LVEF were included, half of whom had OSA as co-morbidity. Forty age- and sex-matched controls were also enrolled. LV structure and function were evaluated by conventional echocardiography and 3DSTE. LV global longitudinal strain (GLS), global circumferential strain (GCS), global area strain (GAS), and global radial strain (GRS) were all measured by 3DSTE.

RESULTS

Four geometric patterns (normal geometry, concentric remodelling, concentric and eccentric hypertrophy) occupied significantly different proportions within the three groups (p = .014). LV remodelling made up higher shares in two T2DM groups than in the controls, whereas LV hypertrophy appeared most frequently in the patients with T2DM and OSA. The patients with T2DM alone had significantly lower GLS and GCS than the controls (both p < .01). The patients with T2DM and OSA had significantly lower GLS, GCS, GAS, and GRS than the controls and the patients with T2DM alone (all p < .01). Fasting plasma glucose (FPG), OSA and BMI had negative impacts on all and part of the strain values in T2DM patients. The T2DM patients with moderate-to-severe OSA showed significantly lower GLS, GCS, GAS, and GRS than those with mild OSA (all p < .05).

CONCLUSIONS

The 3DSTE plus conventional echocardiography could detect the sub-clinical LV alterations in T2DM patients with or without OSA.

Bilirubin is inversely related to diabetic peripheral neuropathy assessed by sural nerve conduction study

AIMS/INTRODUCTION

Diagnosis of diabetic peripheral neuropathy (DPN) depends on subjective findings, certain investigations for DPN risks have not been performed enough. Bilirubin protects against vascular complications by reducing oxidative stress in diabetes, but is not fully tested for DPN. This study aimed to evaluate sural nerve conduction impairments (SNCI) as an objective DPN marker and the contribution of bilirubin to SNCI.

MATERIALS AND METHODS

Using DPN-Check® , SNCI was defined as a decline of amplitude potential or conduction velocity below the normal limit in 150 inpatients with diabetes. The correlations between SNCI and conventional DPN diagnosis criteria, the incidence of diabetic retinopathy/nephropathy, biomarkers for atherosclerosis, cardiac function by ultrasonic cardiogram, and bilirubin were statistically tested, followed by the comparison of logistic regression models for SNCI to find confounders with bilirubin.

RESULTS

The incidence of SNCI was 72.0%. The sensitivity and specificity of SNCI for DPN prediagnosis by simplified criteria were 54.6 and 90.5%, respectively, and similarly corresponded with diabetic retinopathy and nephropathy (sensitivity 57.4 and 50.0%, respectively). SNCI significantly related to diabetes duration, declined estimated glomerular filtration rate, albuminuria and total bilirubin. SNCI incidence was attenuated in the higher bilirubin tertiles (89.8/65.3/54.8%, P < 0.001). Bilirubin was an independent inverse risk factor for SNCI, even after adjustment by known risk factors for DPN and markers for microvascular complications.

CONCLUSIONS

SNCI is a comprehensive marker for diabetic complications. We first showed the independent inverse relationship between bilirubin and SNCI through the independent pathway with other complications, provably reducing oxidative stress, as previously reported.

Serum Bilirubin Level Predicts Frontal QRS-T Angle Change in Patients with Acute Coronary Syndrome

Introduction: The predictive role of serum bilirubin levels on the alteration of total ischemic burden expressed via frontal QRS-T angle change has never been studied in patients with acute coronary syndrome (ACS). In this study, we aimed to investigate the relationship between serum bilirubin levels and frontal QRS-T angle change after percutaneous coronary intervention (PCI) in ACS patients.

Methods: Frontal QRS-T angle change was accepted as positive or negative according to whether the value of the baseline frontal QRS-T angle minus the post PCI frontal QRS-T angle is positive or negative. A total of 314 consecutive patients with ACS who underwent PCI were divided into two groups based on their negative frontal QRS-T angle change (n = 152 patients) and positive frontal QRS-T angle change (n = 162 patients).

Results: Multivariate logistic regression analysis showed that the C-reactive protein (CRP) to albumin ratio (CAR) (Odds ratio [OR]: 0.519, 95% CI: 0.373–0.724, p <0.001), total bilirubin (OR: 3.687, 95% CI: 1.151–8.095, p = 0.03), and low-density lipoprotein (LDL) (OR: 0.985, 95% CI: 0.970–1.000, p = 0.04) were independent predictors of positive QRS-T angle change. In receiver operating characteristics curve analysis, a cut-off value of 0.59 total bilirubin had a 69% sensitivity and a 65% specificity (area under curve: 0.739, p <0.001) for the prediction of positive QRS-T angle change.

Conclusion: In ACS patients, serum total bilirubin has been found to be a useful decision-making tool to predict positive frontal QRS-T angle change as a sign of reduced total ischemic burden, to assess early invasive strategy independently from other study parameters.

The role of microbiota in neonatal hyperbilirubinemia

Hyperbilirubinemia accounts for about 60% of full-term and 80% of preterm neonates globally, which is characterized by physiologically elevated unconjugated bilirubin in serum, but abnormally high levels of bilirubin have potential neurotoxic effects. Several factors contribute to the development of neonatal hyperbilirubinemia, including isoimmunization, dysregulated gut flora, genetic alteration and environmental factors. Animal studies have pinpointed the causal roles of several bacteria in bilirubin metabolism. Human studies have revealed microbiota composition in hyperbilirubinemia and found that gut microbiota affect newborns with different severity of hyperbilirubinemia. However, dysbiosis and subsequent changes in microbiota-related metabolic processes are not always considered. This review aims to describe the critical microbiota signatures for neonatal hyperbilirubinemia and focus on the underlying pathogenetic mechanism. These scientific bases give a new and accurate therapeutic strategy for the application of gut microbiota.

Bilirubin Safeguards Cardiorenal and Metabolic Diseases: a Protective Role in Health

PURPOSE OF REVIEW

To discuss recent advances indicating that bilirubin safeguards against cardiorenal and metabolic diseases.

RECENT FINDINGS

Several investigations from human patient populations and experimental animal models have shown that bilirubin improves cardiorenal and metabolic dysfunction. The latest studies found an entirely new function of bilirubin suggesting that it acts as a hormone signaling molecule capable of activating nuclear receptors for burning fat, which may explain several of its protective actions. This review highlights the current findings (within the last 3 years) regarding cardiorenal and metabolic protective effects of bilirubin and the latest mechanism(s) that may be mediating these effects.

Prognostic Value of Serum Total Bilirubin after Percutaneous Coronary Intervention in Patients with Acute Coronary Syndrome

Backgrounds

Previous studies have reported a relationship between serum total bilirubin (STB) and coronary artery disease (CAD). However, the relationship between STB and prognosis of patients with acute coronary syndrome (ACS) after percutaneous coronary intervention (PCI) remains inconclusive. The present study aimed to evaluate the relationship between STB level and prognosis of PCI in patients with ACS.

Methods

In total, 2850 ACS patients who underwent PCI at the Affiliated Zhongda Hospital of Southeast University from June 2009 to Jan 2017 were included in the study. Twenty-four-hour STB, 30-day, and 1-year postoperative major adverse cardiovascular events (MACE) were recorded. Subjects were assigned to one of three groups based on STB: Group A (STB ≤ 9.6 μmol/L), Group B (9.7 μmol/L < STB ≤ 15.4 μmol/L), and Group C (STB ≥ 15.5 μmol/L). COX survival analysis was subsequently used to investigate the relationship between the incidence of MACE and STB in the three groups.

Results

A total of 2770 subjects were successfully followed up; within 1 year after PCI, 115 (4.15%) subjects died and 191 (6.90%) subjects experienced MACE. One-year follow-up results showed that the incidence of MACE decreased significantly as STB increased; the risk of Group A was 2.002 times that of Group C (95% CI: 1.342-2.986). Cardiac mortality also decreased with increasing STB; the risk of Group A was 3.403 times that of Group C (95% CI: 1.319-8.785).

Conclusion

Lower mortality and MACE incidence rates were found in patients with higher STB within 1 year. Therefore, STB is highly recommended as an independent long-term prognosis predictor of PCI in patients with ACS.