Increased large VLDL and small LDL particles are related to lower bilirubin in Type 2 diabetes mellitus

Maternal pea fiber supplementation to a high calorie diet in obese pregnancies protects male offspring from metabolic dysfunction in adulthood

We investigated the influence of maternal yellow-pea fiber supplementation in obese pregnancies on offspring metabolic health in adulthood. Sixty newly-weaned female Sprague-Dawley rats were randomized to either a low-calorie control diet (CON) or high calorie obesogenic diet (HC) for 6-weeks. Obese animals were then fed either the HC diet alone or the HC diet supplemented with yellow-pea fiber (HC + FBR) for an additional 4-weeks prior to breeding and throughout gestation and lactation. On postnatal day (PND) 21, 1 male and 1 female offspring from each dam were weaned onto the CON diet until adulthood (PND 120) for metabolic phenotyping. Adult male, but not female, HC offspring demonstrated increased body weight and feed intake vs CON offspring, however no protection was offered by maternal FBR supplementation. HC male and female adult offspring demonstrated increased serum glucose and insulin resistance (HOMA-IR) compared with CON offspring. Maternal FBR supplementation improved glycemic control in male, but not female offspring. Compared with CON offspring, male offspring from HC dams demonstrated marked dyslipidemia (higher serum cholesterol, increased number of TG-rich lipoproteins, and smaller LDL particles) which was largely normalized in offspring from HC + FBR mothers. Male offspring born to obese mothers (HC) had higher hepatic TG, which tended to be lowered (p = 0.07) by maternal FBR supplementation.Supplementation of a maternal high calorie diet with yellow-pea fiber in prepregnancy and throughout gestation and lactation protects male offspring from metabolic dysfunction in the absence of any change in body weight status in adulthood.

Both LDL and HDL particle concentrations associate positively with an increased risk of developing microvascular complications in patients with type 2 diabetes: lost protection by HDL (Zodiac-63)

BACKGROUND

Triglyceride-rich lipoproteins (TRL) and low-density lipoproteins (LDL) are associated positively whereas high-density lipoproteins (HDL) are associated inversely with the development of new-onset type 2 diabetes (T2D). Here we studied potential associations between these lipoprotein particle concentrations and the risk of developing microvascular complications in patients with established T2D.

METHODS

Lipoprotein particle concentrations (TRLP, LDLP, and HDLP) were determined in 278 patients with T2D participating in a primary care-based longitudinal cohort study (Zwolle Outpatient Diabetes project Integrating Available Care [ZODIAC] study) leveraging the Vantera nuclear magnetic resonance (NMR) platform using the LP4 algorithm. Associations between lipoprotein particles and incident microvascular complications (nephropathy, neuropathy, and retinopathy) were assessed using Cox proportional hazards regression models.

RESULTS

In total, 136 patients had microvascular complications at baseline. During a median follow-up of 3.2 years, 49 (34.5%) of 142 patients without microvascular complications at baseline developed new-onset microvascular complications. In multivariable Cox proportional hazards regression analyses, both total LDLP and HDLP concentrations, but not total TRLP concentrations, were positively associated with an increased risk of developing any microvascular complications after adjustment for potential confounding factors, including age, sex, disease duration, HbA1c levels, history of macrovascular complications, and statin use (adjusted hazard ratio [HR] per 1 SD increment: 1.70 [95% CI 1.24-2.34], P < 0.001 and 1.63 [95% CI 1.19-2.23], P = 0.002, respectively). When analyzing each microvascular complication individually, total LDLP concentrations were positively associated with retinopathy (adjusted HR 3.35, 95% CI 1.35-8.30, P = 0.009) and nephropathy (adjusted HR 2.13, 95% CI 1.27-3.35, P = 0.004), and total HDLP concentrations with neuropathy (adjusted HR 1.77, 95% CI 1.15-2.70, P = 0.009). No significant associations were observed for lipoprotein particle subfractions.

CONCLUSIONS

Total lipoprotein particle concentrations of both LDL and HDL associate positively with an increased risk of developing microvascular complications in T2D. We propose that the protective role of HDL on the development of microvascular complications may be lost in established T2D.

Total Bilirubin Yields Prognostic Information Following a Myocardial Infarction in the Elderly

Total bilirubin consists of an unconjugated form, solubilized by its binding to albumin, and a conjugated form representing a minor part of the circulating bilirubin. As total bilirubin in physiological concentrations is a powerful antioxidant, its concentration gradient may reflect the health status of an individual, and serve as a prognostic indicator of outcome in primary and secondary cardiovascular disease prevention. The aim of this study was to assess the association between total bilirubin and incident cardiovascular events following a myocardial infarction. Total bilirubin in serum was measured at baseline 2-8 weeks after hospitalization for an MI in 881 patients, aged 70 to 82 years, included in the OMEMI (Omega-3 Fatty acids in Elderly with Myocardial Infarction) study, where patients were followed-up for up to 2 years. The first major adverse clinical event (MACE) was the primary endpoint and consisted of nonfatal MI, unscheduled coronary revascularization, stroke, hospitalization for heart failure or all-cause death. As total bilirubin was non-normally distributed, log-transformed values and quartiles of bilirubin were analyzed using Cox regression models. The median (Q1, and Q3) baseline concentration of bilirubin was 11 (9, and 14) µmol/L, and higher log-transformed concentrations were associated with male sex, lower New York Heart Association (NYHA) class and non-smoking. MACE occurred in 177 (20.1%) patients during the follow-up. Higher concentrations of bilirubin were associated with a lower risk of MACE: HR 0.67 (95%CI 0.47-0.97) per log-unit increase, p = 0.032. Patients in the lowest quartile of bilirubin (<9 µmol/L) had the highest risk with HR 1.61 (95%CI 1.19-2.18), p = 0.002, compared to quartiles 2-4. This association remained significant even after adjusting for age, sex, body mass index (BMI), smoking status, NYHA class and treatment allocation: HR 1.52 (1.21-2.09), p = 0.009. Low concentrations of bilirubin (<9 µmol/L) are associated with increased nonfatal cardiovascular events or death in elderly patients with a recent myocardial infarction.

Serum bilirubin levels are negatively associated with atherogenic lipids in Saudi subjects with type 2 diabetes: A pilot study

<b>Background: </b>Recent research has demonstrated the possible relevance of bilirubin in metabolic and cardiovascular disorders. Lipid abnormalities are a major problem that is related with an increased risk of cardiovascular disease in diabetics. This study examined the relationship between serum bilirubin and direct bilirubin concentrations and atherogenic lipids in patients with type 2 diabetes (T2DM).<br /> <b>Methods</b>: This cross-sectional included 67 patients with type 2 diabetes and 39 matched healthy control. The lipid profile, including total cholesterol, HDL-C, and TG levels, fasting blood glucose, total bilirubin, direct bilirubin, ALT, AST, and ALP were measured using a dimension EXL clinical chemistry analyzer (Siemens Healthcare Diagnostics). Cholesterol in VLDL, LDL, and sdLDL were calculated from standard lipid assay results by the equations of Sampson et al.<br /> <b>Results</b>: Serum bilirubin was lower in non T2DM subjects nearly significant (p=0.0.51) whereas direct bilirubin concentrations were lower in T2DM (p=0.008). ALT, AST, and ALP levels were higher in T2DM groups. The mean values of LDL-C, sdLDL-C, non HDL-C and VLDL-C were significantly increased in T2DM group and lower HDL-C. An inverse relationship could be observed with increase in serum total bilirubin and serum levels of LDL-C (r²=0.139, p&lt;0.005), sdLDL-C (r²=0.137, p&lt;0.005), VLDL-C (r²=0.074, p&lt;0.044), and non HDL-C (r²=0.166, p&lt;0.002) in T2DM group. The same inverse relationship was observed with serum direct bilirubin and serum levels of LDL-C (r²=0.133, p&lt;0.006), sdLDL-C (r²=0.172, p&lt;0.001), VLDL-C (r²=0.118, p&lt;0.01), and non HDL-C (r²=0.182, p&lt;0.001) in T2DM group.<br /> <b>Conclusions</b>: A significant negative association was found between serum bilirubin levels and direct serum bilirubin with atherogenic lipids, suggesting that serum bilirubin may protect T2DM patients from development of cardiovascular disease. These findings indicate the need for additional research in a large cohort.

Paradoxical Association Between Baseline Apolipoprotein B and Prognosis in Coronary Artery Disease: A 36,460 Chinese Cohort Study

Background

Apolipoprotein B (ApoB) and low-density lipoprotein cholesterol (LDL-C) were identified targets for blood lipid management among coronary artery disease (CAD) patients. However, previous studies reported an inverse correlation between baseline LDL-C concentration and clinical outcomes. This study aims to explore the definite association between baseline ApoB and long-term prognosis.

Methods

A total of 36,460 CAD patients admitted to Guangdong Provincial People's Hospital were enrolled and categorized into two groups: high ApoB (≥65 mg/dL) group and low ApoB (<65 mg/dL) group. The association between baseline ApoB and long-term all-cause mortality was evaluated by the Kaplan-Meier method, Cox regression analyses and restricted cubic splines.

Results

The overall mortality was 12.49% (n = 4,554) over a median follow-up period of 5.01 years. Patients with low baseline ApoB levels were paradoxically more likely to get a worse prognosis. There was no obvious difference in risk of long-term all-cause mortality when only adjusted for age, gender, and comorbidity (aHR: 1.07, 95% CI: 0.99–1.16). When CONUT and total bilirubin were adjusted, the risk of long-term all-cause mortality would reduce in the low-ApoB (<65 mg/dL) group (aHR: 0.86, 95% CI: 0.78–0.96). In the fully covariable-adjusted model, patients in the ApoB <65 mg/d group had a 10.00% lower risk of long-term all-cause mortality comparing to patients with ApoB ≥65 mg/dL (aHR: 0.90; 95% CI:0.81–0.99).

Conclusion

This study found a paradoxical association between baseline ApoB and long-term all-cause mortality. Malnutrition and bilirubin mainly mediate the ApoB paradox. Increased ApoB concentration remained linearly associated with an increased risk of long-term all-cause mortality.

Higher Serum Bilirubin Levels in Response to Higher Carbohydrate Intake During Early Pregnancy and Lower Gestational Diabetes Mellitus Occurrence in Overweight and Obese Gravidae

Background and Aim: Serum bilirubin levels are recently shown to be a novel protector of gestational diabetes mellitus (GDM), yet whether they could be affected by carbohydrate quality is unclear. We aimed to examine the associations between dietary carbohydrate parameters and serum bilirubin levels during early pregnancy, with further exploration on a potential mediating role of serum bilirubin levels on carbohydrate parameters-GDM pathways. Methods: 260 healthy but overweight or obese gravidae (BMI ≥24 kg/m2) derived from a historical cohort in two hospitals in China were included. The associations between carbohydrate parameters (total carbohydrate intake, glycemic index GI, fiber intake, glycemic load GL) and serum bilirubin levels (total bilirubin, TB and direct bilirubin, DB) and GDM were evaluated by multivariable regression analysis. Generalized structural equation modeling was then applied to perform adjusted mediation analysis. Results: Increased serum bilirubin levels (mmol/L) and decreased GDM occurrence were observed following dietary carbohydrate intake (%E) and GL (g/1,000 kcal) in highest tertile compared to the lowest tertile [carbohydrate: TB: β = 0.926 (95%CI: 0.069, 1.782), DB: β = 0.554 (95%CI: 0.192, 0.916);GL:TB: β = 1.170 (95%CI: 0.339, 2.001); DB: β = 0.369 (95%CI: 0.016, 0.700); carbohydrate: adjusted OR = 0.43 (95%CI:0.19-0.99); GL: adjusted OR = 0.36 (95%CI:0.16, 0.84)]. The mediating effect of carbohydrate intake and GL on GDM through bilirubin levels was evaluated as modest (carbohydrate: 6.2% for TB, 1.3% for DB; GL: 8.7% for TB, 2.3% for DB). No association was observed regarding GI and fiber. Conclusions: Mildly elevated serum bilirubin levels appeared to be in response to higher energies consumed from carbohydrate during early pregnancy in healthy overweight or obese gravidae. However, the mediating effect of bilirubin levels on carbohydrate-GDM pathways is not evident. Larger investigation is further needed for solid evidence.

Triglyceride-rich lipoprotein and LDL particle subfractions and their association with incident type 2 diabetes: the PREVEND study

Background

Triglyceride-rich lipoproteins particles (TRLP) and low density lipoprotein particles (LDLP) vary in size. Their association with β-cell function is not well described. We determined associations of TRLP and LDLP subfractions with β-cell function, estimated as HOMA-β, and evaluated their associations with incident T2D in the general population.

Methods

We included 4818 subjects of the Prevention of Renal and Vascular End-Stage Disease (PREVEND) study without T2D at baseline. TRLP and LDLP subfraction concentrations and their average sizes were measured using the LP4 algorithm of the Vantera nuclear magnetic resonance platform. HOMA-IR was used as measure of insulin resistance. HOMA-β was used as a proxy of β-cell function.

Results

In subjects without T2D at baseline, very large TRLP, and LDL size were inversely associated with HOMA-β, whereas large TRLP were positively associated with HOMA-β when taking account of HOMA-IR. During a median follow-up of 7.3 years, 263 participants developed T2D. In multivariable-adjusted Cox regression models, higher concentrations of total, very large, large, and very small TRLP (reflecting remnants lipoproteins) and greater TRL size were associated with an increased T2D risk after adjustment for relevant covariates, including age, sex, BMI, HDL-C, HOMA-β, and HOMA-IR. On the contrary, higher concentrations of large LDLP and greater LDL size were associated with a lower risk of developing T2D.

Conclusions

Specific TRL and LDL particle characteristics are associated with β-cell function taking account of HOMA-IR. Moreover, TRL and LDL particle characteristics are differently associated with incident T2D, even when taking account of HOMA-β and HOMA-IR.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12933-021-01348-w.

Impact of triglyceride playing on stroke severity correlated to bilirubin

Major lipids making effects on the occurrence of acute ischemic stroke (AIS) is well recognized, but their roles on stroke severity remain uncertain. To explore the exact roles of lipids playing on stroke severity and the possible mechanism, we conduct this observational study.Data was collected from patients with AIS from February 2008 to May 2012. The level of major lipids was compared among AIS groups with different severity and investigated the correlation. Also, the relationship existed between major lipids and bilirubin. Mechanism of major lipids playing on stroke severity was researched to determine if oxidative stress reflected by bilirubin.Lower triglyceride (TG) and higher high density lipoprotein cholesterol (HDL-C) were observed in severe stroke, and obvious correlation existed between TG and stroke severity or HDL-C and stroke severity. TG was associated negatively with direct bilirubin (DBIL) and total bilirubin (TBIL), and lower level of DBIL and TBIL were related to higher quartiles of TG. There was no obvious difference of DBIL and TBIL among the groups of quartiles of HDL-C. TG was the influence factor of stroke severity in severe stroke through multiple univariable logistic regression. But it was not the independent influence factor after multivariable logistic regression adjusted by DBIL or TBIL. However, HDL-C was the influence factor of stroke severity through both univariable and multivariable logistic regression.Lower TG or higher HDL-C predicted severer stroke. The effect of TG on stroke severity was mediated by bilirubin, not HDL-C.

Serum bilirubin concentrations and incident coronary heart disease risk among patients with type 2 diabetes: the Dongfeng-Tongji cohort

AIMS

Elevated serum bilirubin levels are associated with decreased coronary heart disease (CHD) risk in cross-sectional studies among diabetic patients, but prospective evidence is limited. We investigated the relationship of serum bilirubin levels with incident CHD risk among type 2 diabetes patients.

METHODS

In a prospective study of 2918 type 2 diabetes embedded in the Dongfeng-Tongji cohort, serum total bilirubin (TBil), direct bilirubin (DBil), and indirect bilirubin (IBil) were measured at baseline. Cox proportional hazards models were used to examine the association between serum bilirubin levels and CHD risk.

RESULTS

A total of 440 CHD cases were identified during 12,017 person-years of follow-up. Compared with extreme quartiles, the adjusted hazard ratio and 95% confidence interval of incident CHD were 0.74 (0.56-0.99) with P trend = 0.08 in IBil, while in TBil and DBil, the bilirubin-CHD associations were not significant. Moreover, serum TBil and IBil levels were interacted with drinking status on the risk of incident CHD (P interaction = 0.021 and 0.037, respectively), and the associations were evident in ever drinkers. In drinkers, when serum TBil or IBil concentrations increased 1 μmol/L, the CHD risk both decreased 6% (95% CIs 0.89-0.99 and 0.87-1.00, respectively).

CONCLUSIONS

Serum IBil levels were marginally related to decreased incident CHD risk among type 2 diabetes. Drinking could potentially enhance the associations of serum TBil and DBil levels with incident CHD risk.

Higher direct bilirubin levels during mid-pregnancy are associated with lower risk of gestational diabetes mellitus

Bilirubin concentrations have been recently reported to be negatively associated with type 2 diabetes mellitus. We examined the association between bilirubin concentrations and gestational diabetes mellitus. In a prospective cohort study, 2969 pregnant women were recruited prior to 16 weeks of gestation and were followed up until delivery. The value of bilirubin was tested and oral glucose tolerance test was conducted to screen gestational diabetes mellitus. The relationship between serum bilirubin concentration and gestational weeks was studied by two-piecewise linear regression. A subsample of 1135 participants with serum bilirubin test during 16-18 weeks gestation was conducted to research the association between serum bilirubin levels and risk of gestational diabetes mellitus by logistic regression. Gestational diabetes mellitus developed in 8.5 % of the participants (223 of 2969). Two-piecewise linear regression analyses demonstrated that the levels of bilirubin decreased with gestational week up to the turning point 23 and after that point, levels of bilirubin were increased slightly. In multiple logistic regression analysis, the relative risk of developing gestational diabetes mellitus was lower in the highest tertile of direct bilirubin than that in the lowest tertile (RR 0.60; 95 % CI, 0.35-0.89). The results suggested that women with higher serum direct bilirubin levels during the second trimester of pregnancy have lower risk for development of gestational diabetes mellitus.

Analysis of Lipoprotein Subfractions in 920 Patients With and Without Type 2 Diabetes

BACKGROUND

It has been demonstrated that diabetic dyslipidaemia is the chief bridge between diabetes and incremental risk of cardiovascular disease in patients with diabetes. However, the characteristics of lipoprotein subfractions distribution in patients with type 2 diabetes (T2D) have not been fully investigated. The aim of present study was to evaluate the distributions of lipoprotein subfractions in T2D patients.

METHODS

A total of 920 patients, who have not received lipid-lowering drug treatment previously, were consecutively enrolled in this study. Based on the evidence of diabetes, patients were divided into T2D group (n=204) and non-T2D group (n=716). Both low- and high-density lipoprotein cholesterol (LDL- and HDL-C) subfractions were analysed using the Quantimetrix Lipoprint System. The distributions of lipoprotein subfractions were evaluated in patients with and without T2D.

RESULTS

Compared with non-T2D individuals, the T2D group manifested significantly lower large HDL-C concentration/HDL subfraction percentage, smaller mean LDL particle size but higher small HDL-C and LDL-C concentrations as well as small HDL and LDL subfraction percentages. Moreover, the data indicated that the small HDL-C/ LDL-C concentrations, the small and large HDL subfraction percentages along with the mean LDL particle size were independently related to the existence of T2D (95% CI=1.009-1.067, p=0.009; 95% CI=0.938-0.983, p=0.001; 95% CI=1.023-1.135, p=0.005; 95% CI= 1.005-1.048, p=0.014; 95% CI=0.940-0.999, p=0.040; respectively) assessed by logistic regression analysis.

CONCLUSIONS

The present study indicated that the changes of lipid profile in patients with T2D are characterised by abnormal distributions of lipoprotein subfractions apart from clinically atherogenic dyslipidaemia.

Low-normal thyroid function and novel cardiometabolic biomarkers

The concept is emerging that low-normal thyroid function, i.e., either higher thyroid-stimulating hormone or lower free thyroxine levels within the euthyroid reference range, could contribute to the development of atherosclerotic cardiovascular disease. It is possible that adverse effects of low-normal thyroid function on cardiovascular outcome may be particularly relevant for specific populations, such as younger people and subjects with high cardiovascular risk. Low-normal thyroid function probably relates to modest increases in plasma total cholesterol, low density lipoprotein cholesterol, triglycerides and insulin resistance, but effects on high density lipoprotein (HDL) cholesterol and non-alcoholic fatty liver disease are inconsistent. Low-normal thyroid function may enhance plasma cholesteryl ester transfer, and contribute to an impaired ability of HDL to inhibit oxidative modification of LDL, reflecting pro-atherogenic alterations in lipoprotein metabolism and HDL function, respectively. Low-normal thyroid function also confers lower levels of bilirubin, a strong natural anti-oxidant. Remarkably, all these effects of low-normal thyroid functional status appear to be more outspoken in the context of chronic hyperglycemia and/or insulin resistance. Collectively, these data support the concept that low-normal thyroid function may adversely affect several processes which conceivably contribute to the pathogenesis of atherosclerotic cardiovascular disease, beyond effects on conventional lipoprotein measures.

Bilirubin, platelet activation and heart disease: a missing link to cardiovascular protection in Gilbert's syndrome?

Gilbert's syndrome (GS) is a relatively common condition, inducing a benign, non-hemolytic, unconjugated hyperbilirubinemia. Gilbert's Syndrome is associated with mutation in the Uridine Glucuronosyl Transferase 1A1 (UGT1A1) gene promoter, reducing UGT1A1 activity, which normally conjugates bilirubin allowing its elimination from the blood. Individuals with GS demonstrate mildly elevated plasma antioxidant capacity caused by elevated levels of unconjugated bilirubin (UCB), reduced thiols and glutathione. Interestingly, the development of, and risk of mortality from, cardiovascular disease is remarkably reduced in GS individuals. An explanation for this protection may be explained by bilirubin's ability to inhibit multiple processes that induce platelet hyper-reactivity and thrombosis, thus far under-appreciated in the literature. Reactive oxygen species are produced continuously via metabolic processes and have the potential to oxidatively modify proteins and lipids within cell membranes, which may encourage the development of thrombosis and CVDs. Oxidative stress induced platelet hyper-reactivity significantly increases the risk of thrombosis, which can potentially lead to tissue infarction. Here, we discuss the possible mechanisms by which increased antioxidant status might influence platelet function and link this to cardiovascular protection in GS. In summary, this is the first article to discuss the possible role of bilirubin as an anti-thrombotic agent, which inhibits platelet activation and potentially, organ infarction, which could contribute to the reduced mortality rate in mildly hyperbilirbinemic individuals.